Effects of remifentanil dose on surgical conditions during endoscopic sinus surgery

Effects of remifentanil dose on surgical conditions during endoscopic sinus surgery | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Effects of remifentanil dose on surgical conditions during endoscopic sinus surgery JinHyeok Jeong, ChanWoo Park, SangYun Cho, YoungJoon Yoon, DoJae Lee This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-2833834/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 29 Aug, 2023 Read the published version in BMC Anesthesiology → Version 1 posted 8 You are reading this latest preprint version Abstract Background The combination of propofol and remifentanil results in better surgical field conditions during endoscopic sinus surgery than inhalation anaesthesia. This study compared surgical field conditions between groups receiving low or high concentration of remifentanil. Methods Fifty-four patients, ASA I or II were used to assign the patients to either the high-concentration remifentanil group (HR), targeted at 8 ng/mL or the low-concentration remifentanil group (LR), target was 4 ng/mL Surgical condition was evaluated using the Boezaart Surgical Field Grading Scale presented by Boezaart. Discussion When comparing the HR group and the LR group, the surgeon observed a significant difference in surgical conditions. The reason was the significant decrease in cardiac output. This reduction was because of the effect of remifentanil on reducing heart rate rather than stroke volume. Trial Registration Clinical Trial Registry of the Republic of Korea ( KCT0006453) Endoscopic sinus surgery Remifentanil Surgical field condition Figures Figure 1 Figure 2 Background Endoscopic sinus surgery is an important treatment method for sinusitis and is most often performed under general anaesthesia[ 1 ]. One of the major drawbacks of performing surgery under general anaesthesia is increased bleeding, which can cause difficulty in manipulating the endoscope due to decreased visibility[ 2 ]. Many studies have been conducted to reduce bleeding during surgery, and total intravenous anaesthesia (TIVA) using the combination of intravenous anaesthetic propofol and the opioid remifentanil can reduce bleeding and improve surgical conditions (SC) compared to inhalational anaesthesia[ 3 ]. The primary objective of this study was to compare high-concentration (8 ng/ml) remifentanil use to low-concentration (4 ng/ml) remifentanil use on the conditions of surgery. The secondary objective was to compare hemodynamic variables of cardiac output, stroke volume, heart rate, and mean arterial pressure between the two groups. Methods - Study subjects The subjects were 54 patients between the ages of 18 and 65 years who were rated as American Society of Anesthesiology Classification I or II. Exclusion criteria were: 1) patients with allergies to eggs or soybean oil; 2) patients with a history of drug abuse; and 3) patients receiving other medical treatment, e.g., for hypertension, diabetes, or other conditions. After obtaining approval from the hospital’s institutional review board (Hanyang University Guri Hospital Institutional Review Board, GURI 2012-03-041-006) and registering with the clinical research information service centre ( KCT0006453, Date of registration:17/08/2021, Principal Investigator: SY Cho), this study was performed in accordance with the relevant guidelines and regulations. This study was in accordance with the declaration of Helsinki. Written informed consent was obtained from the patients who voluntarily agreed to participate in the study. The subjects were randomly classified into a high-concentration remifentanil group (HR) and a low-concentration remifentanil group (LR) using computer-generated numbers. - Research methods After the patient arrived at the operating room, electrocardiogram, pulse oxygen saturation, non-invasive blood pressure, and end-tidal carbon dioxide pressure were measured. Depth of anaesthesia was measured using a bispectral index (BIS) monitor (A-2000TM, version 3.3, Aspect Medical Systems Inc., Newton, MA, USA). After administering 100% oxygen for three min to the patient, 40 mg of 1% lidocaine was administered intravenously. Using a target concentration-controlled injector (Orchestra, Fresenius-Vial, Brezins, France), propofol was administered at an effect-site concentration of 6.0 µg/ml using a Schnider pharmacokinetic model. Remifentanil was administered at an effect-site concentration of 2.0–4.0 ng/ml using the Minto pharmacokinetic model. During administration of propofol and remifentanil, the patient received the instruction "open your eyes" every 10 seconds. If the patient could not open their eyes, the muscle relaxant esmeron was injected at a dose of 0.6 mg/kg. When the BIS level dropped below 60 and the train of four (TOF) on the nerve stimulator reached zero, endotracheal intubation was performed. Administration of remifentanil during anesthesia maintenance was performed by a target-controlled infusion (TCI) device with an effective site concentration of 8 ng/ml in the high-concentration group and of 4 ng/ml in the low-concentration group. The TCI device was prepared in advance, and the fixed concentration of drug was sealed. The anesthesiologist who administered the anesthesia was, therefore, blinded to the concentration of remifentanil used. The effect-site concentration of propofol was adjusted by 0.2 µg/ml from the initial concentration to maintain a BIS value of 40–60. At the end of the operation, propofol and remifentanil were discontinued; pyridostigmine 0.2 mg/kg and glycopyrrolate 0.008 mg/kg were injected intravenously to reverse the muscle relaxant effects; and extubation was performed under the influence of a nerve stimulator. Baseline systolic arterial pressure (SAP), diastolic arterial pressure (DAP), mean arterial pressure (MAP), heart rate (HR), BIS, stroke volume (SV), and cardiac output (CO) levels were measured immediately after arrival at the operating room. The variables also were measured immediately after endotracheal intubation and at 30, 60, and 90 minutes after the start of surgery, for observation and comparison. Stroke volume and cardiac output were measured using non-invasive cardiac monitoring, for which the CSN-1901 (Nihon Kohden, Tokyo, Japan) was used. Evaluation of the surgical condition was conducted by a single operator using the Boezaart surgical field grading scale (Table 1 )[ 4 ] and was recorded at 30, 60, and 90 minutes after the start of surgery. Table 1 Surgical Grading Scoring System Designed Specifically for Use in Endoscopic Sinus Surgery Grade Assessment 0 No bleeding (cadaveric conditions) 1 Slight bleeding – no suction required 2 Slight bleeding – occasional suction required 3 Slight bleeding – frequent suctioning requied; bleeding threatens surgical field a few seconds after suction is removed 4 Moderate bleeding – frequent suction ing required and bleeding threatens surgical field directly after suction is removed 5 Severe bleeding – constant suctioning requied; bleeding appears faster than can be removed by suction; surgical field severely threatened and surgery usually not possible The total doses of propofol and remifentanil administered during anesthesia were recorded. After 30 minutes and within 24 hours of recovery room arrival, the Visual Analog Scale (VAS) and Postoperative Nausea and Vomiting (PONV) score were measured. The PONV score was divided into 4 categories, 0 = none, 1 = nausea, 2 = retching, and 3 = vomiting. -Sample size calculation We used the mean and standard deviation from pilot study (mean and standard deviation: 2.3 and 0.57). In a two-tailed analysis where α = 0.05 and β = 80%, 24.1 patients were required to obtain a 20% difference in the mean between the experimental and control groups. A total of 54 patients were required to maintain acceptable statistical power, assuming a 10% dropout rate. - Statistics The Statistical Package for Social Sciences 20.0 for Windows (SPSS Inc., IL, USA) was used as a statistical program. The Mann-Whitney rank sum test was performed to compare numerical data between the two groups, and the χ2 test and Fisher's exact test were used for non-parametric data. Kruskal-Wallis one-way analysis of variance with a Dunn multiple comparison test was used to assess haemodynamic change. The statistical significance level was set at p = 0.05. Results All 54 patients who participated in the study met the inclusion criteria, and none refused to participate. These patients were randomly assigned to a high-concentration or low-concentration group, with 27 patients in each group (Fig. 1 ). Subject data and clinical characteristics are presented in Table 2 . There was no significant difference between the two groups in terms of mean age, gender, height, weight, body mass index, ASA score, and operation and anaesthesia times. Table 2 Demographic Data and Clinical Characteristics of Patients Group LR (n = 27) Group HR (n = 27) Age (yr) 44 ± 12.0 47.1 ± 13.0 Gender (M/F) 9/18 9/18 Height (cm) 167.1 ± 8.8 167.6 ± 9.0 Weight (kg) 69.7 ± 13.0 69.1 ± 14.3 Body mass index (kg/m 2 ) 25.0 ± 4.1 24.5 ± 3.4 ASA (I/II) 10/17 11/16 Operation time (min) 108.3 ± 30.0 102.8 ± 22.8 Anaesthesia time (min) 138.3 ± 28.2 135.7 ± 22.0 Values are number or mean ± SD. Group LR: low remifentanil group, Group HR: high remifentanil group, ASA: American Society of Anesthesiologists physical status. Haemodynamic variables between the two groups were measured through non-invasive cardiac monitoring (Table 3 ). For cardiac output, there was a statistically significant decrease in the HR compared to the LR group immediately after endotracheal intubation and at 30, 60, and 90 minutes after the start of surgery (cardiac output, base; p = 0.222, intubation; p = 0.016, 30 min; p = 0.014, 60 min; p = 0.012, 90 min; p = 0.008). However, for stroke volume, there was no significant difference between the two groups in all measurements (stroke volume, base; p = 0.482, intubation; p = 0.461, 30 min; p = 0.258, 60 min; p = 0.263, 90 min; p = 0.603). Table 3 Haemodynamic Parameters Group LR (n = 27) Group HR (n = 27) Cardiac output, Base 7.20 ± 1.45 6.31 ± 2.34 Cardiac output, Intubation 7.34 ± 1.32 5.87 ± 1.81* Cardiac output, 30 6.32 ± 1.28 5.00 ± 1.53* Cardiac output, 60 6.45 ± 1.47 4.98 ± 1.56* Cardiac output, 90 6.83 ± 1.37 5.18 ± 1.83* Stroke volume, Base 92.4 ± 14.4 87.8 ± 20.7 Stroke volume, Intubation 88.2 ± 14.5 83.9 ± 17.0 Stroke volume, 30 89.3 ± 16.1 82.5 ± 16.9 Stroke volume, 60 88.5 ± 16.4 81.4 ± 18.1 Stroke volume, 90 88.1 ± 14.9 84.8 ± 19.8 The values are measured by non-invasive cardiac monitoring with CSN-1901. Base: preoperative control values; Intubation: immediately after intubation; 30, 60, and 90: 30 min, 60 min, and 90 min, respectively, after beginning the operation. *p < 0.05 compared to Group LR. The changes in heart rate between the two groups [Fig. 2 . (a)] were significantly lower in the high-concentration group compared to the low-concentration group immediately after endotracheal intubation and at 30, 60, and 90 minutes after the start of surgery (heart rate changes, base; P = 0.412, intubation; p = 0.033, 30 min; p = 0.005, 60 min; p = 0.002, 90 min; p = 0.001). Mean arterial pressure [Fig. 2 (b)] and systolic blood pressure [Fig. 2 (c)] decreased in the high-concentration group compared to the low-concentration group immediately after endotracheal intubation and at 30 minutes after the start of surgery; however, these differences were not statistically significant. At 60 and 90 minutes after the start of surgery, the high-concentration group showed statistically lower MAP and SBP than the high-concentration group (mean arterial pressure, base; p = 0.692, intubation; p = 0.765, 30 min; p = 0.121, 60 min; p = 0.006, 90 min; p = 0.025, systolic arterial pressure, base; p = 0.786, intubation; p = 0.144, 30 min; p = 0.081, 60 min; p = 0.039, 90 min; p = 0.019). Surgical conditions (Table 4 ) did not show significant differences between the two groups at 30 and 60 minutes after the start of surgery. However, at 90 minutes after the start of surgery, the high-concentration group showed a significantly lower score than the low-concentration group (surgical score, 30 min; p = 0.315, 60 min; p = 0.269, 90 min; p = 0.021). There was no significant difference between the two groups in terms of postoperative pain, nausea, and vomiting (VAS score, p = 0.991, PONV score, p = 0.077). Table 4 Changes of Surgical Scores and Other Parameters During Endoscopic Sinus Surgery Group LR (n = 27) Group HR (n = 27) Surgical score, 30 2.33 ± 0.62 2.56 ± 0.63 Surgical score, 60 2.67 ± 0.62 2.44 ± 0.51 Surgical score, 90 2.80 ± 0.68 2.25 ± 0.58* Total propofol dose (mg) 1127.4 ± 374.5 984.2 ± 304.1 Total remifentanil dose (mcg) 1221.2 ± 347.3 2192 ± 719.2* VAS 4.19 ± 2.24 4.19 ± 2.35 PONV 0.11 ± 0.32 0.00 ± 0.00 VAS: visual analogue score, PONV: postoperative nausea and vomiting. *p < 0.05 compared to Group LR. Discussion This study demonstrated a significant decrease in surgical score in the high-concentration group after 90 minutes of surgery compared to the low-concentration group. Cardiac output was also significantly decreased. Endoscopic sinus surgery is an important treatment for chronic sinusitis and identification of anatomical landmarks within the limited surgical field of view is important for successful surgery[ 3 ]. Under general anaesthesia, increased bleeding may obscure endoscopic surgical visibility and hinder surgery. This can lead to complications such as increased postoperative haemorrhage, cerebrospinal fluid leakage, and visual loss[ 5 ]. To reduce these risks, use of the reverse Trendelenburg position, topical decongestants, and vasoconstrictors has been suggested[ 6 ]. In addition, controlled hypotension using general anaesthesia has been used to reduce bleeding during endoscopic sinus surgery[ 7 ]. Use of drugs such as vasodilators, sodium nitroprusside, or beta-blockers has also been suggested to reduce blood pressure[ 8 – 10 ]. Total intravenous combination anaesthesia using intravenous anaesthetic propofol and the opioid remifentanil is also widely used to reduce intraoperative bleeding by reducing cardiac output without rapidly decreasing systemic vascular resistance. 3 Remifentanil, an ultrashort-acting synthetic opioid, may show a synergistic effect with propofol during total intravenous anaesthesia, causing a decrease in cardiac output. This is probably due to the bradycardia-inducing effect along with a blood pressure-lowering effect[ 11 ]. In this study, we confirmed that heart rate decreased significantly in the high-concentration group compared to the low-concentration group. Several reports have suggested that the bradycardic effect of remifentanil is associated with its central vagotonic effect[ 12 ]. A significant decrease in cardiac output was also observed in the high-dose group. However, stroke volume did not show a significant difference between the two groups. Based on these results, the decrease of cardiac output in the high-concentration group appears to be more strongly related to decrease in heart rate than to decrease in stroke volume. Cheong et al[ 13 ]. reported neither a decrease in myocardial contractility proportional to the increase in remifentanil usage nor a compensatory increase in myocardial contractility with a decrease in heart rate. Manola et al.[ 14 ] reported that the blood pressure-lowering effect of remifentanil was due to the reduction of cardiac output rather than peripheral vasodilation. In this study, there was a significant MAP difference between the two groups at 60 min and 90 min after start of the surgery. Surgical conditions, a measure of the quality of the endoscopic view, showed a significant difference between the two groups at 90 minutes after the start of surgery. Based on these results, we confirmed that use of high-concentration remifentanil can cause a decrease in cardiac output and can assist the surgeon in maintaining the necessary view during endoscopic surgery. In this study, cardiac output and stroke volume were measured through non-invasive cardiac monitoring (CSN-1901). CSN-1901 monitoring is based on pulse wave transit time and indirectly measures cardiac output and stroke volume through the R-wave of the electrocardiogram, the pulse waves of the pulse oximeter, and blood pressure. Traditionally, cardiac output has been measured through an invasive method such as a pulmonary artery catheter; the use of this measurement method is gradually decreasing, while the use of non-invasive measurement methods is increasing[ 15 , 16 ]. Saugel et al.[ 15 ] compared the types and mechanisms of non-invasive cardiac monitoring with invasive measurement methods, and Jeon et al.[ 17 ] reported that use of the CSN-1901 is helpful to estimate intravascular volume status. A limitation of this study may be the surgical grading system that evaluated the surgical field of view. In this study, the surgical condition was evaluated through the Boezaart grading scale. This evaluation method is widely used because of its simplicity but is somewhat subjective and remains unstandardized. Athanasiadis et al.[ 2 ] reported that most reported scores on the Boezaart grading scale were 2 or 3 points, hindering detection of subtle differences in the surgical field. Also, inter-rater reliability was lower than with the Wormald surgical field grading scale. In addition, since scoring is performed using a subjective numerical scale, reviewer bias may occur; and the score at 30 minutes after the start of surgery may affect the scores at 60 and 90 minutes after the start of surgery. A further study is needed to compare the measured values using different methods of cardiac output monitoring. In this study, cardiac monitoring was based on pulse wave transit time. If we can compare the results of this study with cardiac output measurement through echocardiography, in-depth testing of the reliability and accuracy of non-invasive monitoring will be possible. In conclusion, when comparing the HR group with the LR group, there was a marked difference in surgical conditions as graded by the surgeon. The reason for this is that cardiac output significantly decreased when a high concentration of remifentanil was used because of remifentanil’s effect on reducing heart rate rather than stroke volume. Declarations Declaration of interests: The authors declare that they have no conflict of interest. Ethics approval and consent to participate This study was approved by the the hospital’s institutional review board (Hanyang University Guri Hospital Institutional Review Board, GURI 2012-03-041-006) and registered with the clinical research information service centre (KCT0006453, Date of registration:17/08/2021, Principal Investigator: SY Cho). This study was in accordance with the declaration of Helsinki and performed in accordance with the relevant guidelines and regulations. All patients voluntarily participated in the study and signed informed consent before the surgery. Consent for publication Not applicable Availability of data and materials The datasets used and analyzed during the current study are available from the corresponding author on reasonable request Competing interests The authors declare that they have no competing interests Funding Not applicable Author’s contributions JHJ, CWP, YJY, DJL, SYC: revised this manuscript. All authors have read and approved final manuscript Acknowledgements The authors thank the Hanyang University E-world center for considerable help during the preparation of the manuscript. References Cho K, Lee JY, Park SK, Cheong SH, Lee KM, Lim SH, et al. Comparison of surgical conditions during propofol or desflurane anesthesia for endoscopic sinus surgery. Korean J Anesthesiol 2012; 63: 302-7. Athanasiadis T, Beule A, Embate J, Steinmeier E, Field J, Wormald PJ. Standardized video‐endoscopy and surgical field grading scale for endoscopic sinus surgery: a multi‐centre study. Laryngoscope 2008; 118: 314-9. Brunner JP, Levy JM, Ada ML, Tipirneni KE, Barham HP, Oakley GM, et al. Total intravenous anesthesia improves intraoperative visualization during surgery for high‐grade chronic rhinosinusitis: a double‐blind randomized controlled trial. Int Forum Allergy Rhinol. 2018, 1114-22. Boezaart AP, van der Merwe J, Coetzee A. Comparison of sodium nitroprusside-and esmolol-induced controlled hypotension for functional endoscopic sinus surgery. Can J Anaesth 1995; 42: 373-6. Stankiewicz JA, Lal D, Connor M, Welch K. Complications in endoscopic sinus surgery for chronic rhinosinusitis: a 25‐year experience. Laryngoscope 2011; 121: 2684-701. DeConde AS, Thompson CF, Wu EC, Suh JD. Systematic review and meta‐analysis of total intravenous anesthesia and endoscopic sinus surgery. Int Forum Allergy Rhinol. 2013, 848-54. Ahn H, Chung S-K, Dhong H-J, Kim H, Ahn J, Lee S, et al. Comparison of surgical conditions during propofol or sevoflurane anaesthesia for endoscopic sinus surgery. Br J Anaesth 2008; 100: 50-4. Kelly EA, Gollapudy S, Riess ML, Woehlck HJ, Loehrl TA, Poetker DM. Quality of surgical field during endoscopic sinus surgery: a systematic literature review of the effect of total intravenous compared to inhalational anesthesia. Int Forum Allergy Rhinol. 2013, 474-81. Cho SY, Cheong M, Kim KH, Kim DW, Jun JH, Suh JK, et al. The Comparison of Propofol and Sodium Nitroprusside in Induced Hypotension undergoing Endoscopic Sinus Surgery. Korean J Anesthesiol 1998; 34: 359-64. Nekhendzy V, Lemmens HJM, Vaughan WC, Hepworth EJ, Chiu AG, Church CA, et al. The effect of deliberate hypercapnia and hypocapnia on intraoperative blood loss and quality of surgical feild during endoscopic sinus surgery. Anesth Analg 2007;105:1404-9. Degoute C-S, Ray M-J, Manchon M, Dubreuil C, Banssillon V. Remifentanil and controlled hypotension; comparison with nitroprusside or esmolol during tympanoplasty. Can J Anaesth 2001; 48: 20-7. Shinohara K, Aono H, Unruh GK, Kindscher JD, Goto H. Suppressive effects of remifentanil on hemodynamics in baro-denervated rabbits. Can J Anaesth 2000; 47: 361-6. Cheong S-H, Park T-S, Lee S-E, Kim Y-H, Lim S-H, Lee J-H, et al. Measurement of Hemodynamic Variables using Impedance Cardiography on Remifentanil-Propofol Infusion during Anesthetic Induction. Korean J Anesthesiol 2007; 53. Manola M, De Luca E, Moscillo L, Mastella A. Using remifentanil and sufentanil in functional endoscopic sinus surgery to improve surgical conditions. ORL 2005; 67: 83-6. Saugel B, Thiele RH, Hapfelmeier A, Cannesson M. Technological assessment and objective evaluation of minimally invasive and noninvasive cardiac output monitoring systems. Anesthesiology 2020; 133: 921-8. Nguyen LS, Squara P. Non-invasive monitoring of cardiac output in critical care medicine. Front Med 2017; 4: 200. Jeon WJ, Shin WJ, Yoon YJ, Park CW, Shim JH, Cho SY. Anesthetics management of a renal angiomyolipoma using pulse pressure variation and non-invasive cardiac output monitoring: A case report. World J Clin Cases 2022; 10: 8656-61. Additional Declarations No competing interests reported. Cite Share Download PDF Status: Published Journal Publication published 29 Aug, 2023 Read the published version in BMC Anesthesiology → Version 1 posted Editorial decision: Major revision 27 Jun, 2023 Reviews received at journal 08 Jun, 2023 Reviewers agreed at journal 07 Jun, 2023 Reviewers invited by journal 07 Jun, 2023 Editor assigned by journal 07 Jun, 2023 Editor invited by journal 07 Jun, 2023 Submission checks completed at journal 24 May, 2023 First submitted to journal 18 Apr, 2023 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-2833834","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":203565346,"identity":"b36a0d19-c517-4c80-9da3-e75c456d3886","order_by":0,"name":"JinHyeok Jeong","email":"","orcid":"","institution":"Hanyang University Guri Hospital","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"JinHyeok","middleName":"","lastName":"Jeong","suffix":""},{"id":203565349,"identity":"5b12a3fc-123e-4a22-b308-21253e1330ea","order_by":1,"name":"ChanWoo Park","email":"","orcid":"","institution":"Hanyang University Guri Hospital","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"ChanWoo","middleName":"","lastName":"Park","suffix":""},{"id":203565352,"identity":"98e95632-892d-4de1-ac0b-d3f6f726f942","order_by":2,"name":"SangYun Cho","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA5ElEQVRIiWNgGAWjYDACCRBRcQBJhIcoLWdI1sLYRooW/tnNhz/zzrsjby6R/OzhFwY7eQaesw/wW3LnWJo077ZnhjtnpJkbyzAkGzbwthvg1WIgkWPGzLvtMOOGGwlm0hIMzAkM/Gz4HQbUYvyZd85h+w030r8BtdQTpcVAmrfhcOKGGzlmkh8YDicw8Lbh1yJxIy1Ncs6xw8kbzrwpk2YwOG7YxnMMvxb+GcmHP7ypOWy74Xj6NskfFdXy/Dxp+LWAABM4JgQSGJh5gGFFwCcQwPgDbN8BKGMUjIJRMApGARoAAHYPQsx8X7DtAAAAAElFTkSuQmCC","orcid":"","institution":"Hanyang University Guri Hospital","correspondingAuthor":true,"submittingAuthor":false,"prefix":"","firstName":"SangYun","middleName":"","lastName":"Cho","suffix":""},{"id":203565354,"identity":"f5f74471-5712-447c-8180-36a40042d2ec","order_by":3,"name":"YoungJoon Yoon","email":"","orcid":"","institution":"Hanyang University Guri Hospital","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"YoungJoon","middleName":"","lastName":"Yoon","suffix":""},{"id":203565357,"identity":"621ae544-9851-45ba-bc6c-2f9206379c1d","order_by":4,"name":"DoJae Lee","email":"","orcid":"","institution":"Hanyang University Guri Hospital","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"DoJae","middleName":"","lastName":"Lee","suffix":""}],"badges":[],"createdAt":"2023-04-18 21:59:16","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-2833834/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-2833834/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1186/s12871-023-02253-3","type":"published","date":"2023-08-29T15:09:19+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":37542229,"identity":"182c46f4-6a38-42e1-96b2-cdfcc53e60da","added_by":"auto","created_at":"2023-05-26 14:41:41","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":135807,"visible":true,"origin":"","legend":"\u003cp\u003eSubject flow diagram\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-2833834/v1/02fda7743d91c2857a7430ba.png"},{"id":37542228,"identity":"93d724f4-e1e6-4505-8d3e-68ab12f2243f","added_by":"auto","created_at":"2023-05-26 14:41:41","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":81987,"visible":true,"origin":"","legend":"\u003cp\u003e(a) Changes of heart rate in groups LR and HR. Base: preoperative control values; Intubation: right after intubation; HR 30, 60, and 90: 30, 60, and 90 respective min after beginning the operation. *p \u0026lt; 0.05 compared to Group LR.\u003c/p\u003e\n\u003cp\u003e(b) Changes of mean arterial pressure in groups LR and HR. Base: preoperative control values; Intubation: right after intubation; HR 30, 60, and 90: 30, 60, and 90 respective min after beginning the operation. *p \u0026lt; 0.05 compared to Group LR.\u003c/p\u003e\n\u003cp\u003e(c) Changes of systolic arterial pressure in groups LR and HR. Base: preoperative control values; Intubation: right after intubation; HR 30, 60, and 90: 30, 60, and 90 respective min after beginning the operation. *p \u0026lt; 0.05 compared to Group LR.\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-2833834/v1/e5442afa51f038d720d29f9c.png"},{"id":42782204,"identity":"23ebf2fd-868e-4ebb-bc60-b41222d826c5","added_by":"auto","created_at":"2023-09-07 15:16:23","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":617315,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-2833834/v1/8d2a8a35-3fd2-43a3-a2e4-3e40a2fa22c8.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Effects of remifentanil dose on surgical conditions during endoscopic sinus surgery","fulltext":[{"header":"Background","content":"\u003cp\u003eEndoscopic sinus surgery is an important treatment method for sinusitis and is most often performed under general anaesthesia[\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]. One of the major drawbacks of performing surgery under general anaesthesia is increased bleeding, which can cause difficulty in manipulating the endoscope due to decreased visibility[\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eMany studies have been conducted to reduce bleeding during surgery, and total intravenous anaesthesia (TIVA) using the combination of intravenous anaesthetic propofol and the opioid remifentanil can reduce bleeding and improve surgical conditions (SC) compared to inhalational anaesthesia[\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eThe primary objective of this study was to compare high-concentration (8 ng/ml) remifentanil use to low-concentration (4 ng/ml) remifentanil use on the conditions of surgery. The secondary objective was to compare hemodynamic variables of cardiac output, stroke volume, heart rate, and mean arterial pressure between the two groups.\u003c/p\u003e "},{"header":"Methods","content":"\u003cp\u003e- Study subjects\u003c/p\u003e\u003cp\u003eThe subjects were 54 patients between the ages of 18 and 65 years who were rated as American Society of Anesthesiology Classification I or II. Exclusion criteria were: 1) patients with allergies to eggs or soybean oil; 2) patients with a history of drug abuse; and 3) patients receiving other medical treatment, e.g., for hypertension, diabetes, or other conditions. After obtaining approval from the hospital’s institutional review board (Hanyang University Guri Hospital Institutional Review Board, GURI 2012-03-041-006) and registering with the clinical research information service centre ( KCT0006453, Date of registration:17/08/2021, Principal Investigator: SY Cho), this study was performed in accordance with the relevant guidelines and regulations. This study was in accordance with the declaration of Helsinki. Written informed consent was obtained from the patients who voluntarily agreed to participate in the study. The subjects were randomly classified into a high-concentration remifentanil group (HR) and a low-concentration remifentanil group (LR) using computer-generated numbers.\u003c/p\u003e\u003cp\u003e- Research methods\u003c/p\u003e\u003cp\u003eAfter the patient arrived at the operating room, electrocardiogram, pulse oxygen saturation, non-invasive blood pressure, and end-tidal carbon dioxide pressure were measured. Depth of anaesthesia was measured using a bispectral index (BIS) monitor (A-2000TM, version 3.3, Aspect Medical Systems Inc., Newton, MA, USA). After administering 100% oxygen for three min to the patient, 40 mg of 1% lidocaine was administered intravenously. Using a target concentration-controlled injector (Orchestra, Fresenius-Vial, Brezins, France), propofol was administered at an effect-site concentration of 6.0 µg/ml using a Schnider pharmacokinetic model. Remifentanil was administered at an effect-site concentration of 2.0–4.0 ng/ml using the Minto pharmacokinetic model. During administration of propofol and remifentanil, the patient received the instruction \"open your eyes\" every 10 seconds. If the patient could not open their eyes, the muscle relaxant esmeron was injected at a dose of 0.6 mg/kg. When the BIS level dropped below 60 and the train of four (TOF) on the nerve stimulator reached zero, endotracheal intubation was performed.\u003c/p\u003e\u003cp\u003eAdministration of remifentanil during anesthesia maintenance was performed by a target-controlled infusion (TCI) device with an effective site concentration of 8 ng/ml in the high-concentration group and of 4 ng/ml in the low-concentration group. The TCI device was prepared in advance, and the fixed concentration of drug was sealed. The anesthesiologist who administered the anesthesia was, therefore, blinded to the concentration of remifentanil used. The effect-site concentration of propofol was adjusted by 0.2 µg/ml from the initial concentration to maintain a BIS value of 40–60.\u003c/p\u003e\u003cp\u003eAt the end of the operation, propofol and remifentanil were discontinued; pyridostigmine 0.2 mg/kg and glycopyrrolate 0.008 mg/kg were injected intravenously to reverse the muscle relaxant effects; and extubation was performed under the influence of a nerve stimulator.\u003c/p\u003e\u003cp\u003eBaseline systolic arterial pressure (SAP), diastolic arterial pressure (DAP), mean arterial pressure (MAP), heart rate (HR), BIS, stroke volume (SV), and cardiac output (CO) levels were measured immediately after arrival at the operating room. The variables also were measured immediately after endotracheal intubation and at 30, 60, and 90 minutes after the start of surgery, for observation and comparison. Stroke volume and cardiac output were measured using non-invasive cardiac monitoring, for which the CSN-1901 (Nihon Kohden, Tokyo, Japan) was used. Evaluation of the surgical condition was conducted by a single operator using the Boezaart surgical field grading scale (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e)[\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e] and was recorded at 30, 60, and 90 minutes after the start of surgery.\u003c/p\u003e\u003cdiv class=\"gridtable\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eSurgical Grading Scoring System Designed Specifically for Use in Endoscopic Sinus Surgery\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e\u003ccolgroup cols=\"2\"\u003e\u003c/colgroup\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eGrade\u003c/p\u003e \u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eAssessment\u003c/p\u003e \u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eNo bleeding (cadaveric conditions)\u003c/p\u003e \u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eSlight bleeding – no suction required\u003c/p\u003e \u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e2\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eSlight bleeding – occasional suction required\u003c/p\u003e \u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e3\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eSlight bleeding – frequent suctioning requied; bleeding threatens surgical field a few seconds after suction is removed\u003c/p\u003e \u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e4\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eModerate bleeding – frequent suction ing required and bleeding threatens surgical field directly after suction is removed\u003c/p\u003e \u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e5\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eSevere bleeding – constant suctioning requied; bleeding appears faster than can be removed by suction; surgical field severely threatened and surgery usually not possible\u003c/p\u003e \u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/table\u003e\u003c/div\u003e\u003cp\u003eThe total doses of propofol and remifentanil administered during anesthesia were recorded.\u003c/p\u003e\u003cp\u003eAfter 30 minutes and within 24 hours of recovery room arrival, the Visual Analog Scale (VAS) and Postoperative Nausea and Vomiting (PONV) score were measured. The PONV score was divided into 4 categories, 0 = none, 1 = nausea, 2 = retching, and 3 = vomiting.\u003c/p\u003e\u003cp\u003e-Sample size calculation\u003c/p\u003e\u003cp\u003eWe used the mean and standard deviation from pilot study (mean and standard deviation: 2.3 and 0.57). In a two-tailed analysis where α = 0.05 and β = 80%, 24.1 patients were required to obtain a 20% difference in the mean between the experimental and control groups. A total of 54 patients were required to maintain acceptable statistical power, assuming a 10% dropout rate.\u003c/p\u003e\u003cp\u003e- Statistics\u003c/p\u003e\u003cp\u003eThe Statistical Package for Social Sciences 20.0 for Windows (SPSS Inc., IL, USA) was used as a statistical program. The Mann-Whitney rank sum test was performed to compare numerical data between the two groups, and the χ2 test and Fisher's exact test were used for non-parametric data. Kruskal-Wallis one-way analysis of variance with a Dunn multiple comparison test was used to assess haemodynamic change. The statistical significance level was set at p = 0.05.\u003c/p\u003e"},{"header":"Results","content":"\u003cp\u003eAll 54 patients who participated in the study met the inclusion criteria, and none refused to participate. These patients were randomly assigned to a high-concentration or low-concentration group, with 27 patients in each group (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eSubject data and clinical characteristics are presented in Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e. There was no significant difference between the two groups in terms of mean age, gender, height, weight, body mass index, ASA score, and operation and anaesthesia times.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eDemographic Data and Clinical Characteristics of Patients\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"3\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eGroup LR (n\u0026thinsp;=\u0026thinsp;27)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eGroup HR (n\u0026thinsp;=\u0026thinsp;27)\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eAge (yr)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e44\u0026thinsp;\u0026plusmn;\u0026thinsp;12.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e47.1\u0026thinsp;\u0026plusmn;\u0026thinsp;13.0\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eGender (M/F)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e9/18\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e9/18\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eHeight (cm)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e167.1\u0026thinsp;\u0026plusmn;\u0026thinsp;8.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e167.6\u0026thinsp;\u0026plusmn;\u0026thinsp;9.0\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eWeight (kg)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e69.7\u0026thinsp;\u0026plusmn;\u0026thinsp;13.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e69.1\u0026thinsp;\u0026plusmn;\u0026thinsp;14.3\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eBody mass index (kg/m\u003c/b\u003e\u003csup\u003e\u003cb\u003e2\u003c/b\u003e\u003c/sup\u003e\u003cb\u003e)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e25.0\u0026thinsp;\u0026plusmn;\u0026thinsp;4.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e24.5\u0026thinsp;\u0026plusmn;\u0026thinsp;3.4\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eASA (I/II)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e10/17\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e11/16\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eOperation time (min)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e108.3\u0026thinsp;\u0026plusmn;\u0026thinsp;30.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e102.8\u0026thinsp;\u0026plusmn;\u0026thinsp;22.8\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eAnaesthesia time (min)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e138.3\u0026thinsp;\u0026plusmn;\u0026thinsp;28.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e135.7\u0026thinsp;\u0026plusmn;\u0026thinsp;22.0\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"3\"\u003eValues are number or mean\u0026thinsp;\u0026plusmn;\u0026thinsp;SD. Group LR: low remifentanil group, Group HR: high remifentanil group, ASA: American Society of Anesthesiologists physical status.\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eHaemodynamic variables between the two groups were measured through non-invasive cardiac monitoring (Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e). For cardiac output, there was a statistically significant decrease in the HR compared to the LR group immediately after endotracheal intubation and at 30, 60, and 90 minutes after the start of surgery (cardiac output, base; p\u0026thinsp;=\u0026thinsp;0.222, intubation; p\u0026thinsp;=\u0026thinsp;0.016, 30 min; p\u0026thinsp;=\u0026thinsp;0.014, 60 min; p\u0026thinsp;=\u0026thinsp;0.012, 90 min; p\u0026thinsp;=\u0026thinsp;0.008). However, for stroke volume, there was no significant difference between the two groups in all measurements (stroke volume, base; p\u0026thinsp;=\u0026thinsp;0.482, intubation; p\u0026thinsp;=\u0026thinsp;0.461, 30 min; p\u0026thinsp;=\u0026thinsp;0.258, 60 min; p\u0026thinsp;=\u0026thinsp;0.263, 90 min; p\u0026thinsp;=\u0026thinsp;0.603).\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab3\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 3\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eHaemodynamic Parameters\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"3\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\"\u0026plusmn;\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\"\u0026plusmn;\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eGroup LR (n\u0026thinsp;=\u0026thinsp;27)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eGroup HR (n\u0026thinsp;=\u0026thinsp;27)\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCardiac output, Base\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003e7.20\u0026thinsp;\u0026plusmn;\u0026thinsp;1.45\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003e6.31\u0026thinsp;\u0026plusmn;\u0026thinsp;2.34\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCardiac output, Intubation\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003e7.34\u0026thinsp;\u0026plusmn;\u0026thinsp;1.32\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003e5.87\u0026thinsp;\u0026plusmn;\u0026thinsp;1.81*\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eCardiac output, 30\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003e6.32\u0026thinsp;\u0026plusmn;\u0026thinsp;1.28\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e5.00\u0026thinsp;\u0026plusmn;\u0026thinsp;1.53*\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eCardiac output, 60\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003e6.45\u0026thinsp;\u0026plusmn;\u0026thinsp;1.47\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e4.98\u0026thinsp;\u0026plusmn;\u0026thinsp;1.56*\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eCardiac output, 90\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003e6.83\u0026thinsp;\u0026plusmn;\u0026thinsp;1.37\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e5.18\u0026thinsp;\u0026plusmn;\u0026thinsp;1.83*\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eStroke volume, Base\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003e92.4\u0026thinsp;\u0026plusmn;\u0026thinsp;14.4\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e87.8\u0026thinsp;\u0026plusmn;\u0026thinsp;20.7\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eStroke volume, Intubation\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003e88.2\u0026thinsp;\u0026plusmn;\u0026thinsp;14.5\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e83.9\u0026thinsp;\u0026plusmn;\u0026thinsp;17.0\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eStroke volume, 30\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003e89.3\u0026thinsp;\u0026plusmn;\u0026thinsp;16.1\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e82.5\u0026thinsp;\u0026plusmn;\u0026thinsp;16.9\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eStroke volume, 60\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003e88.5\u0026thinsp;\u0026plusmn;\u0026thinsp;16.4\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e81.4\u0026thinsp;\u0026plusmn;\u0026thinsp;18.1\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eStroke volume, 90\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003e88.1\u0026thinsp;\u0026plusmn;\u0026thinsp;14.9\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e84.8\u0026thinsp;\u0026plusmn;\u0026thinsp;19.8\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"3\"\u003eThe values are measured by non-invasive cardiac monitoring with CSN-1901. Base: preoperative control values; Intubation: immediately after intubation; 30, 60, and 90: 30 min, 60 min, and 90 min, respectively, after beginning the operation. *p\u0026thinsp;\u0026lt;\u0026thinsp;0.05 compared to Group LR.\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eThe changes in heart rate between the two groups [Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e2\u003c/span\u003e. (a)] were significantly lower in the high-concentration group compared to the low-concentration group immediately after endotracheal intubation and at 30, 60, and 90 minutes after the start of surgery (heart rate changes, base; P\u0026thinsp;=\u0026thinsp;0.412, intubation; p\u0026thinsp;=\u0026thinsp;0.033, 30 min; p\u0026thinsp;=\u0026thinsp;0.005, 60 min; p\u0026thinsp;=\u0026thinsp;0.002, 90 min; p\u0026thinsp;=\u0026thinsp;0.001). Mean arterial pressure [Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e2\u003c/span\u003e(b)] and systolic blood pressure [Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e2\u003c/span\u003e (c)] decreased in the high-concentration group compared to the low-concentration group immediately after endotracheal intubation and at 30 minutes after the start of surgery; however, these differences were not statistically significant. At 60 and 90 minutes after the start of surgery, the high-concentration group showed statistically lower MAP and SBP than the high-concentration group (mean arterial pressure, base; p\u0026thinsp;=\u0026thinsp;0.692, intubation; p\u0026thinsp;=\u0026thinsp;0.765, 30 min; p\u0026thinsp;=\u0026thinsp;0.121, 60 min; p\u0026thinsp;=\u0026thinsp;0.006, 90 min; p\u0026thinsp;=\u0026thinsp;0.025, systolic arterial pressure, base; p\u0026thinsp;=\u0026thinsp;0.786, intubation; p\u0026thinsp;=\u0026thinsp;0.144, 30 min; p\u0026thinsp;=\u0026thinsp;0.081, 60 min; p\u0026thinsp;=\u0026thinsp;0.039, 90 min; p\u0026thinsp;=\u0026thinsp;0.019).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eSurgical conditions (Table\u0026nbsp;\u003cspan refid=\"Tab4\" class=\"InternalRef\"\u003e4\u003c/span\u003e) did not show significant differences between the two groups at 30 and 60 minutes after the start of surgery. However, at 90 minutes after the start of surgery, the high-concentration group showed a significantly lower score than the low-concentration group (surgical score, 30 min; p\u0026thinsp;=\u0026thinsp;0.315, 60 min; p\u0026thinsp;=\u0026thinsp;0.269, 90 min; p\u0026thinsp;=\u0026thinsp;0.021). There was no significant difference between the two groups in terms of postoperative pain, nausea, and vomiting (VAS score, p\u0026thinsp;=\u0026thinsp;0.991, PONV score, p\u0026thinsp;=\u0026thinsp;0.077).\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab4\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 4\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eChanges of Surgical Scores and Other Parameters During Endoscopic Sinus Surgery\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"3\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\"\u0026plusmn;\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\"\u0026plusmn;\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eGroup LR (n\u0026thinsp;=\u0026thinsp;27)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eGroup HR (n\u0026thinsp;=\u0026thinsp;27)\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSurgical score, 30\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2.33\u0026thinsp;\u0026plusmn;\u0026thinsp;0.62\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003e2.56\u0026thinsp;\u0026plusmn;\u0026thinsp;0.63\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSurgical score, 60\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2.67\u0026thinsp;\u0026plusmn;\u0026thinsp;0.62\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003e2.44\u0026thinsp;\u0026plusmn;\u0026thinsp;0.51\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eSurgical score, 90\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003e2.80\u0026thinsp;\u0026plusmn;\u0026thinsp;0.68\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e2.25\u0026thinsp;\u0026plusmn;\u0026thinsp;0.58*\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eTotal propofol dose (mg)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003e1127.4\u0026thinsp;\u0026plusmn;\u0026thinsp;374.5\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e984.2\u0026thinsp;\u0026plusmn;\u0026thinsp;304.1\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eTotal remifentanil dose (mcg)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003e1221.2\u0026thinsp;\u0026plusmn;\u0026thinsp;347.3\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e2192\u0026thinsp;\u0026plusmn;\u0026thinsp;719.2*\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eVAS\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003e4.19\u0026thinsp;\u0026plusmn;\u0026thinsp;2.24\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e4.19\u0026thinsp;\u0026plusmn;\u0026thinsp;2.35\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003ePONV\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003e0.11\u0026thinsp;\u0026plusmn;\u0026thinsp;0.32\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e0.00\u0026thinsp;\u0026plusmn;\u0026thinsp;0.00\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"3\"\u003eVAS: visual analogue score, PONV: postoperative nausea and vomiting. *p\u0026thinsp;\u0026lt;\u0026thinsp;0.05 compared to Group LR.\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eThis study demonstrated a significant decrease in surgical score in the high-concentration group after 90 minutes of surgery compared to the low-concentration group. Cardiac output was also significantly decreased.\u003c/p\u003e \u003cp\u003eEndoscopic sinus surgery is an important treatment for chronic sinusitis and identification of anatomical landmarks within the limited surgical field of view is important for successful surgery[\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]. Under general anaesthesia, increased bleeding may obscure endoscopic surgical visibility and hinder surgery. This can lead to complications such as increased postoperative haemorrhage, cerebrospinal fluid leakage, and visual loss[\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]. To reduce these risks, use of the reverse Trendelenburg position, topical decongestants, and vasoconstrictors has been suggested[\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e]. In addition, controlled hypotension using general anaesthesia has been used to reduce bleeding during endoscopic sinus surgery[\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. Use of drugs such as vasodilators, sodium nitroprusside, or beta-blockers has also been suggested to reduce blood pressure[\u003cspan additionalcitationids=\"CR9\" citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e]. Total intravenous combination anaesthesia using intravenous anaesthetic propofol and the opioid remifentanil is also widely used to reduce intraoperative bleeding by reducing cardiac output without rapidly decreasing systemic vascular resistance.\u003csup\u003e3\u003c/sup\u003e\u003c/p\u003e \u003cp\u003eRemifentanil, an ultrashort-acting synthetic opioid, may show a synergistic effect with propofol during total intravenous anaesthesia, causing a decrease in cardiac output. This is probably due to the bradycardia-inducing effect along with a blood pressure-lowering effect[\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e]. In this study, we confirmed that heart rate decreased significantly in the high-concentration group compared to the low-concentration group. Several reports have suggested that the bradycardic effect of remifentanil is associated with its central vagotonic effect[\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e]. A significant decrease in cardiac output was also observed in the high-dose group. However, stroke volume did not show a significant difference between the two groups. Based on these results, the decrease of cardiac output in the high-concentration group appears to be more strongly related to decrease in heart rate than to decrease in stroke volume. Cheong et al[\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]. reported neither a decrease in myocardial contractility proportional to the increase in remifentanil usage nor a compensatory increase in myocardial contractility with a decrease in heart rate.\u003c/p\u003e \u003cp\u003eManola et al.[\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e] reported that the blood pressure-lowering effect of remifentanil was due to the reduction of cardiac output rather than peripheral vasodilation. In this study, there was a significant MAP difference between the two groups at 60 min and 90 min after start of the surgery. Surgical conditions, a measure of the quality of the endoscopic view, showed a significant difference between the two groups at 90 minutes after the start of surgery. Based on these results, we confirmed that use of high-concentration remifentanil can cause a decrease in cardiac output and can assist the surgeon in maintaining the necessary view during endoscopic surgery.\u003c/p\u003e \u003cp\u003eIn this study, cardiac output and stroke volume were measured through non-invasive cardiac monitoring (CSN-1901). CSN-1901 monitoring is based on pulse wave transit time and indirectly measures cardiac output and stroke volume through the R-wave of the electrocardiogram, the pulse waves of the pulse oximeter, and blood pressure. Traditionally, cardiac output has been measured through an invasive method such as a pulmonary artery catheter; the use of this measurement method is gradually decreasing, while the use of non-invasive measurement methods is increasing[\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e, \u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e]. Saugel et al.[\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e] compared the types and mechanisms of non-invasive cardiac monitoring with invasive measurement methods, and Jeon et al.[\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e] reported that use of the CSN-1901 is helpful to estimate intravascular volume status.\u003c/p\u003e \u003cp\u003eA limitation of this study may be the surgical grading system that evaluated the surgical field of view. In this study, the surgical condition was evaluated through the Boezaart grading scale. This evaluation method is widely used because of its simplicity but is somewhat subjective and remains unstandardized. Athanasiadis et al.[\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e] reported that most reported scores on the Boezaart grading scale were 2 or 3 points, hindering detection of subtle differences in the surgical field. Also, inter-rater reliability was lower than with the Wormald surgical field grading scale. In addition, since scoring is performed using a subjective numerical scale, reviewer bias may occur; and the score at 30 minutes after the start of surgery may affect the scores at 60 and 90 minutes after the start of surgery.\u003c/p\u003e \u003cp\u003eA further study is needed to compare the measured values using different methods of cardiac output monitoring. In this study, cardiac monitoring was based on pulse wave transit time. If we can compare the results of this study with cardiac output measurement through echocardiography, in-depth testing of the reliability and accuracy of non-invasive monitoring will be possible.\u003c/p\u003e \u003cp\u003eIn conclusion, when comparing the HR group with the LR group, there was a marked difference in surgical conditions as graded by the surgeon. The reason for this is that cardiac output significantly decreased when a high concentration of remifentanil was used because of remifentanil\u0026rsquo;s effect on reducing heart rate rather than stroke volume.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eDeclaration of interests:\u003c/strong\u003e The authors declare that they have no conflict of interest.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003cstrong\u003eEthics approval and consent to participate\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis study was approved by the\u0026nbsp;the hospital\u0026rsquo;s institutional review board (Hanyang University Guri Hospital Institutional Review Board, GURI 2012-03-041-006)\u0026nbsp;and\u0026nbsp;registered with the clinical research information service centre (KCT0006453,\u0026nbsp;Date of registration:17/08/2021, Principal Investigator: SY Cho). This study was in accordance with the declaration of Helsinki and performed in accordance with the relevant guidelines and regulations.\u0026nbsp;All patients voluntarily participated in the study and signed informed consent before the surgery.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003cstrong\u003eConsent for publication\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNot applicable\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003cstrong\u003eAvailability of data and materials\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe datasets used and analyzed during the current study are available from the corresponding author on reasonable request\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003cstrong\u003eCompeting interests\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors declare that they have no competing interests\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNot applicable\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003cstrong\u003eAuthor\u0026rsquo;s contributions\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eJHJ, CWP, YJY, DJL, SYC: revised this manuscript.\u003c/p\u003e\n\u003cp\u003eAll authors have read and approved final manuscript\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003cstrong\u003eAcknowledgements\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors thank the Hanyang University E-world center for considerable help during the preparation of the manuscript.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eCho K, Lee JY, Park SK, Cheong SH, Lee KM, Lim SH, et al. Comparison of surgical conditions during propofol or desflurane anesthesia for endoscopic sinus surgery. Korean J Anesthesiol 2012; 63: 302-7.\u003c/li\u003e\n\u003cli\u003eAthanasiadis T, Beule A, Embate J, Steinmeier E, Field J, Wormald PJ. Standardized video‐endoscopy and surgical field grading scale for endoscopic sinus surgery: a multi‐centre study. Laryngoscope 2008; 118: 314-9.\u003c/li\u003e\n\u003cli\u003eBrunner JP, Levy JM, Ada ML, Tipirneni KE, Barham HP, Oakley GM, et al. Total intravenous anesthesia improves intraoperative visualization during surgery for high‐grade chronic rhinosinusitis: a double‐blind randomized controlled trial. Int Forum Allergy Rhinol. 2018, 1114-22.\u003c/li\u003e\n\u003cli\u003eBoezaart AP, van der Merwe J, Coetzee A. Comparison of sodium nitroprusside-and esmolol-induced controlled hypotension for functional endoscopic sinus surgery. Can J Anaesth 1995; 42: 373-6.\u003c/li\u003e\n\u003cli\u003eStankiewicz JA, Lal D, Connor M, Welch K. Complications in endoscopic sinus surgery for chronic rhinosinusitis: a 25‐year experience. Laryngoscope 2011; 121: 2684-701.\u003c/li\u003e\n\u003cli\u003eDeConde AS, Thompson CF, Wu EC, Suh JD. Systematic review and meta‐analysis of total intravenous anesthesia and endoscopic sinus surgery. Int Forum Allergy Rhinol. 2013, 848-54.\u003c/li\u003e\n\u003cli\u003eAhn H, Chung S-K, Dhong H-J, Kim H, Ahn J, Lee S, et al. Comparison of surgical conditions during propofol or sevoflurane anaesthesia for endoscopic sinus surgery. Br J Anaesth 2008; 100: 50-4.\u003c/li\u003e\n\u003cli\u003eKelly EA, Gollapudy S, Riess ML, Woehlck HJ, Loehrl TA, Poetker DM. Quality of surgical field during endoscopic sinus surgery: a systematic literature review of the effect of total intravenous compared to inhalational anesthesia. Int Forum Allergy Rhinol. 2013, 474-81.\u003c/li\u003e\n\u003cli\u003eCho SY, Cheong M, Kim KH, Kim DW, Jun JH, Suh JK, et al. The Comparison of Propofol and Sodium Nitroprusside in Induced Hypotension undergoing Endoscopic Sinus Surgery. Korean J Anesthesiol 1998; 34: 359-64.\u003c/li\u003e\n\u003cli\u003eNekhendzy V, Lemmens HJM, Vaughan WC, Hepworth EJ, Chiu AG, Church CA, et al. The effect of deliberate hypercapnia and hypocapnia on intraoperative blood loss and quality of surgical feild during endoscopic sinus surgery. Anesth Analg 2007;105:1404-9.\u003c/li\u003e\n\u003cli\u003eDegoute C-S, Ray M-J, Manchon M, Dubreuil C, Banssillon V. Remifentanil and controlled hypotension; comparison with nitroprusside or esmolol during tympanoplasty. Can J Anaesth 2001; 48: 20-7.\u003c/li\u003e\n\u003cli\u003eShinohara K, Aono H, Unruh GK, Kindscher JD, Goto H. Suppressive effects of remifentanil on hemodynamics in baro-denervated rabbits. Can J Anaesth 2000; 47: 361-6.\u003c/li\u003e\n\u003cli\u003eCheong S-H, Park T-S, Lee S-E, Kim Y-H, Lim S-H, Lee J-H, et al. Measurement of Hemodynamic Variables using Impedance Cardiography on Remifentanil-Propofol Infusion during Anesthetic Induction. Korean J Anesthesiol 2007; 53.\u003c/li\u003e\n\u003cli\u003eManola M, De Luca E, Moscillo L, Mastella A. Using remifentanil and sufentanil in functional endoscopic sinus surgery to improve surgical conditions. ORL 2005; 67: 83-6.\u003c/li\u003e\n\u003cli\u003eSaugel B, Thiele RH, Hapfelmeier A, Cannesson M. Technological assessment and objective evaluation of minimally invasive and noninvasive cardiac output monitoring systems. Anesthesiology 2020; 133: 921-8.\u003c/li\u003e\n\u003cli\u003eNguyen LS, Squara P. Non-invasive monitoring of cardiac output in critical care medicine. Front Med 2017; 4: 200.\u003c/li\u003e\n\u003cli\u003eJeon WJ, Shin WJ, Yoon YJ, Park CW, Shim JH, Cho SY. Anesthetics management of a renal angiomyolipoma using pulse pressure variation and non-invasive cardiac output monitoring: A case report. World J Clin Cases 2022; 10: 8656-61.\u003c/li\u003e\n\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"bmc-anesthesiology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"bane","sideBox":"Learn more about [BMC Anesthesiology](http://bmcanesthesiol.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/bane","title":"BMC Anesthesiology","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"Endoscopic sinus surgery, Remifentanil, Surgical field condition","lastPublishedDoi":"10.21203/rs.3.rs-2833834/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-2833834/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eBackground The combination of propofol and remifentanil results in better surgical field conditions during endoscopic sinus surgery than inhalation anaesthesia. This study compared surgical field conditions between groups receiving low or high concentration of remifentanil.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMethods \u003c/strong\u003eFifty-four patients, ASA I or II were used to assign the patients to either the high-concentration remifentanil group (HR), targeted at 8 ng/mL or the low-concentration remifentanil group (LR), target was 4 ng/mL Surgical condition was evaluated using the Boezaart Surgical Field Grading Scale presented by Boezaart.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eDiscussion \u003c/strong\u003eWhen comparing the HR group and the LR group, the surgeon observed a significant difference in surgical conditions. The reason was the significant decrease in cardiac output. This reduction was because of the effect of remifentanil on reducing heart rate rather than stroke volume.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTrial Registration \u003c/strong\u003eClinical Trial Registry of the Republic of Korea\u003cstrong\u003e (\u003c/strong\u003eKCT0006453)\u003c/p\u003e","manuscriptTitle":"Effects of remifentanil dose on surgical conditions during endoscopic sinus surgery","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2023-05-26 14:41:36","doi":"10.21203/rs.3.rs-2833834/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Major revision","date":"2023-06-27T09:04:32+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2023-06-08T10:01:07+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"3ea2eef9-4344-4112-b958-2f38f8abe46f","date":"2023-06-07T19:08:31+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2023-06-07T10:56:37+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2023-06-07T10:41:43+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"","date":"2023-06-07T04:56:55+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2023-05-24T17:47:28+00:00","index":"","fulltext":""},{"type":"submitted","content":"BMC Anesthesiology","date":"2023-04-18T21:58:24+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"bmc-anesthesiology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"bane","sideBox":"Learn more about [BMC Anesthesiology](http://bmcanesthesiol.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/bane","title":"BMC Anesthesiology","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"c9723ce1-dbcf-4ebf-bf64-21ce947aecf4","owner":[],"postedDate":"May 26th, 2023","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2023-09-07T15:13:58+00:00","versionOfRecord":{"articleIdentity":"rs-2833834","link":"https://doi.org/10.1186/s12871-023-02253-3","journal":{"identity":"bmc-anesthesiology","isVorOnly":false,"title":"BMC Anesthesiology"},"publishedOn":"2023-08-29 15:09:19","publishedOnDateReadable":"August 29th, 2023"},"versionCreatedAt":"2023-05-26 14:41:36","video":"","vorDoi":"10.1186/s12871-023-02253-3","vorDoiUrl":"https://doi.org/10.1186/s12871-023-02253-3","workflowStages":[]},"version":"v1","identity":"rs-2833834","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-2833834","identity":"rs-2833834","version":["v1"]},"buildId":"WrCJVZZCHTDjtuVLN7oU0","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}