Lidocaine and risk of postoperative vomiting in children undergoing tonsillectomy: a randomised clinical trial

Lidocaine and risk of postoperative vomiting in children undergoing tonsillectomy: a randomised clinical trial | 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 Article Lidocaine and risk of postoperative vomiting in children undergoing tonsillectomy: a randomised clinical trial Yang Hu, Ming-cheng Du, Yi Chen, Xiang Long, Jing-jing Jiang, and 1 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-4474829/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 26 Aug, 2024 Read the published version in Scientific Reports → Version 1 posted 10 You are reading this latest preprint version Abstract The dose-response of intravenous lidocaine for preventing postoperative vomiting (POV) in children is unclear. This study investigated whether intravenous lidocaine dose-dependently decreases POV risk within 24 h postoperatively in children undergoing tonsillectomy (with/without adenoidectomy) without severe complications. Patients aged 3–12 years (American Society of Anesthesiologists grade I–II) scheduled for elective tonsillectomy (with/without adenoidectomy) were enrolled from December 2021 to March 2022. They were randomly grouped according to the lidocaine dose (A [0 mg kg -1 ], B [1 mg kg -1 ], C [1.5 mg kg -1 ], and D [2 mg kg -1 ]) and were administered the same induction protocol (sufentanil, propofol, and suxamethonium chloride). Anaesthesia was maintained using sevoflurane. POV incidence within 24 h postoperatively was 46%, 40%, 36%, and 20% in groups A, B, C, and D, respectively, with significant differences between groups D and A. That of postoperative analgesic rescue in groups A, B, C, and D was 62%, 36%, 34%, and 16%, respectively, with significant differences between groups D and B, C and A, and D and A. No severe adverse events occurred. Intravenous lidocaine (2 mg kg -1 ) dose-dependently decreases POV risk without serious adverse events in children undergoing tonsillectomy (with/without adenoidectomy). Trial registration: Chinese Clinical Trial Registry, ChiCTR2100053006. Biological sciences/Drug discovery/Pharmacology Health sciences/Medical research lidocaine Postoperative vomiting Tonsillectomy Figures Figure 1 Figure 2 Introduction Tonsillectomy is the most common procedure for the treatment of paediatric recurrent acute tonsillitis and tonsillar enlargement. 1 Even though the surgery is safe, common complications include postoperative nausea and vomiting (PONV), throat pain, and bleeding. 2 Children (≥3 years) are at a high risk of PONV, which is the most common cause of dissatisfaction in children and their parents and prolongs hospitalisation. 3 ,4 Numerous interventions have been recommended to decrease the incidence of PONV, especially dexamethasone, a 5-HT3 receptor antagonist. 4 However, the optimal management of PONV remains a challenge for clinical anaesthesiologists owing to the need to balance the benefit of PONV intervention with the risk of adverse effects. Lidocaine has analgesic, antihyperalgesic, and anti-inflammatory properties, making it a general anaesthetic adjuvant. 5 Intravenous lidocaine has antiemetic properties in paediatric patients in combination with other antiemetics. 6,7 The mechanism of lidocaine to reduce PONV is unclear but might be due to the opioid-sparing effect. However, the effect of intravenous lidocaine solely for the prevention of PONV in paediatric tonsillectomy remains unclear. Therefore, we hypothesised that intravenous lidocaine solely may decrease the risk of PONV in a dose-dependent manner in children undergoing tonsillectomy (with or without adenoidectomy) without severe side effects. Owing to the difficulty in assessing nausea in paediatric patients, our trial focused solely on evaluating postoperative vomiting (POV). The selection of POV as the primary outcome was guided by the need for clinically meaningful outcomes with potential benefits. Materials and methods Study design This was a single-centre, parallel-group, randomised, double-blind controlled trial. Ethical approvance was obtained from the Institutional Review Board of Yichang Central People’s Hospital (HEC-KYJJ-2020-038-02) and registered at www.chictr.org.cn (ChiCTR2100053006). The trial was conducted in compliance with the tenets of the Declaration of Helsinki and was registered on 8 November 2021. The study was conducted from 1 December 2021 to 1 March 2022 at Yichang Central People’s Hospital. Written informed consent was obtained from the parents of each child. The patients were randomised in a 1:1 ratio to each group. Randomisation was computer-generated, and each patient was assigned a code. Patients Patients aged 3–12 years (American Society of Anesthesiologists grade I–II) scheduled for elective tonsillectomy (with or without adenoidectomy) were enrolled. The children were divided into four groups: A (0 mg kg -1 lidocaine), B (1 mg kg -1 lidocaine), C (1.5 mg kg -1 lidocaine), and D (2 mg kg -1 lidocaine) (Anhui Changjiang Pharmaceutical Co. Ltd, Wuhu, China). The exclusion criteria were as follows: chronic cough, history of steroid or bronchodilator treatment, respiratory tract reactive disease, upper airway infection in the previous 2 weeks, therapy with angiotensin-converting enzyme inhibitors, gastroesophageal reflux, morbid obesity, known allergy to any of the study drugs, and use of medications and nutraceuticals known to affect blood pressure (BP) and heart rate (HR). Perioperative anaesthetic care Preoperatively, all children fasted for 6 h and were restricted from oral intake of clear fluids for 1 h. The children entered the operating room with their parents to curb their separation anxiety. Noninvasive BP, HR, electrocardiography, and pulse oxygen saturation were measured using a multifunction monitor (GE Healthcare, Helsinki, Finland). The width of the BP cuff for each patient was approximately two-thirds of the upper arm length. After 5 min of stabilisation, the baseline HR, systolic BP, diastolic BP, and mean arterial pressure values were obtained from the average of three measurements taken 2 min apart. A 22-gauge intravenous catheter was subsequently inserted into the veins at the back of the hand. After preoxygenation, the respective treatments were injected over a 3-s period. An anaesthetic nurse who had prepared the study treatments was blinded to the study and administered the injection with pump activation. Two minutes after the injection, general anaesthesia was induced following the induction protocol: sufentanil (Yichang Renfu Pharmaceutical Co. Ltd., Yichang, China) 0.25 μg kg -1 , propofol (Fresenius Kabi Deutschland GmbH, Homburg, Germany) 2.0 mg kg -1 , and suxamethonium chloride (Xi’an Hanfeng Pharmaceutical Co. Ltd., Xi’an, China) 1 mg kg 1 . When eyelash reflexes were absent, the patient was ventilated via a facemask with 100% oxygen. A cuffed endotracheal tube was used, the size of which was selected based on a widely used formula (3.5 + age in years/4). Patients were excluded from the study if any difficulty was encountered during facemask ventilation. After intubation, rocuronium (Zhejiang Xianju Pharmaceutical Co. Ltd., Taizhou, China) 0.3 mg kg -1 was injected to maintain muscle relaxation. Anaesthesia was maintained with 2%–3% sevoflurane (Maruishi Pharmaceutical Co., Ltd., Osaka, Japan) and 50% medical air in oxygen. The surgery was performed by an experienced surgeon. At the end of the operation, sevoflurane was discontinued, and neostigmine (Zhejiang Xianju Pharmaceutical Co. Ltd., Taizhou, China) 0.04 mg kg -1 and atropine (Suicheng Pharmaceutical Co. Ltd., Xinzheng, China) 0.02 mg kg -1 were administered to antagonise any residual neuromuscular blockade. After extubation, an anaesthesiologist who was not involved in the study performed anaesthesia emergence and subsequently graded cough response. Following the completion of the surgery, oral suction was performed immediately after removing the endotracheal tube. Extubation was performed by confirming adequate tidal volume, regular spontaneous respiratory pattern, and purposeful behaviour (eyes open upon request). After extubation, the children were monitored for at least 5 min to resume regular spontaneous respiration and subsequently transferred to the postanaesthesia care unit (PACU). Electrocardiography, peripheral pulse oximetry, and noninvasive BP measurements were performed. Patients were discharged from the PACU to the ward when their Steward recovery score was higher than 4, where they stayed overnight. Other perioperative care was performed according to the practices of local clinicians. If the rating score for pain was ≥3 at rest, as assessed by the Children and Infants Postoperative Pain Scale, 8 intravenous propacetamol 30 mg kg -1 was administered by the attending PACU nurse. Primary outcomes The primary outcome was the incidence of POV within 24 h postoperatively. Rescue methods for POV were intravenous ondansetron 50 μg kg -1 and dexamethasone 0.1 mg kg -1 . Secondary outcomes Secondary outcomes were evaluated to determine the analgesic efficacy of lidocaine. The incidence of children requiring analgesic rescue within 24 h was recorded. Adverse events included laryngospasm, oxygen desaturation, upper airway obstruction, and arrhythmia. Statistical analysis Assuming a 55% rate of PONV 5 (55% for the primary outcome), we found that a sample size of 50 patients would be required to achieve 95% power at a two-sided α level of 0.05 to demonstrate a relative between-group difference of 55% in the composite primary outcome measure (55% to 14%). Patient characteristics (including age, height, and weight), time of surgery, and time to extubation were expressed as means and standard deviations and were analysed using analysis of variance. The incidence of PONV and consumption of analgesics were expressed as a ratio and analysed using χ 2 , with a P value <.05 indicating a difference. Statistical significance was set at P <.01 for all analyses. GraphPad Prism 8.0.2 (GraphPad Software Inc., San Diego, CA, USA) was used for all analyses. Results Patients Between 1 December 2021 and 1 March 2022, 280 patients were enrolled in the study, of whom 200 were included in the analysis and divided into four groups; the demographic characteristics and operative data did not differ between the groups (Table 1). Primary outcomes The incidence of POV was 46% (95% confidence interval [CI]: 32%–61%), 40% (95% CI: 26%–55%), 36% (95% CI: 23%–51%), and 20% (95% CI: 10%–34%) in groups A, B, C, and D, respectively. There was a significant difference between groups D and A ( P ≤.01), with a dose-dependent decrease in POV (Fig. 1). Secondary outcomes The incidence of postoperative analgesic rescue in groups A, B, C, and D was 62% (95% CI, 47%–75%), 36% (95% CI, 23%–51%), 34% (95% CI, 21%–49%), and 16% (95% CI, 7%–29%), respectively. Significant differences were observed between groups D and B and groups C and A ( P ≤.01) and between groups D and A ( P ≤.001) (Fig. 2). There were no significant differences among the groups in the time to extubation, even when this difference was extended to 2 min longer than that in group A (Table 1). Moreover, no severe complications, such as postoperative hypoxaemia, laryngospasm, or arrhythmia, were observed in any group. Table 1. Patient characteristics and clinical data Group A (n=50) Group B (n=50) Group C (n=50) Group D (n=50) Age (years) 5.78±2.04 6.05±2.09 5.63±1.92 6.13±1.92 Height (cm) 120.00±14.68 118.23±23.46 117.08±12.04 121.50±13.47 Weight (kg) 23.95±7.72 23.61±7.69 22.59±7.11 25.99±8.23 Sex (M⁄ F) 23/22 27/18 25/20 28/17 Time of operation (min) 30.18±11.87 29.82±11.78 31.31±14.14 27.15±11.89 Time of extubation (min) 11.69±3.60 13.80±3.47 13.38±3.89 13.33±3.66 Incidence of laryngospasm 0 0 0 0 Incidence of postoperative hypoxemia 0 0 0 0 Incidence of arrhythmia 0 0 0 0 Adenotonsillectomy with/without tonsillectomy 43/2 45/0 45/0 44/1 Values are expressed as the mean±standard deviation or number. †P < 0.05 vs. Group A. ASA, American Society of Anesthesiologists Group A, lidocaine 0 mg kg -1 IV; group B, lidocaine 1 mg kg -1 IV; group C, lidocaine 1.5 mg kg -1 IV; and group D, lidocaine 2 mg kg -1 IV. Discussion The 2020 consensus guidelines for the management of PONV recommend 5-HT3 antagonists and dexamethasone (0.15 mg kg -1 ) as the standard prophylaxis. 4 Dexamethasone is an efficacious antiemetic but is associated with a risk of postoperative bleeding, which is sometimes fatal. 9 5-HT 3 receptor antagonists are commonly used in PONV management and may cause adverse cardiac events, such as arrhythmia. 10 Our results showed that intravenous lidocaine effectively and dose-dependently reduced the incidence of POV in children undergoing tonsillectomy (with or without adenoidectomy) without severe side effects. Only 2 mg kg -1 lidocaine achieved a significantly better clinical effect (20%). Significantly fewer children received rescue analgesics in each group during the first 24 h. Significant differences were observed between groups D and B, groups C and A ( P ≤.01), and groups D and A ( P ≤.001). The reduction in rescue analgesic requirement may not be explained by the analgesic effect of lidocaine because the half-life of lidocaine is 2 h. 11 The mechanism underlying this phenomenon remains unclear and may be associated with the anti-inflammatory effects of intravenous lidocaine. Our trial first found that the single dose of lidocaine needed to achieve an antiemetic effect was higher than that needed to achieve an analgesic effect within 24 h postoperatively. This is due to the multi-model anaesthesia and opioid-sparing effect of lidocaine. There were no significant differences in the clinical characteristics and clinical data between the groups. No severe side effects were observed in this trial. However, in our study, the time of extubation in the groups administered intravenous lidocaine was prolonged by nearly 2 min, which is different from that in other studies. Our study has certain limitations. First, we chose a single dose of lidocaine for the advent of lidocaine accumulation. Second, this was a single-centre study, which reduced the power and reliability of the results. Third, we used the concentration of sevoflurane in the end-expiratory gas to monitor the depth of anaesthesia, potentially leading to an increased incidence of POV. In conclusion, our study revealed that intravenous lidocaine solely decreased the incidence of PONV in children undergoing tonsillectomy (with or without adenoidectomy) in a dose-dependent manner. No serious adverse events were observed after the administration of different doses of intravenous lidocaine. Declarations Data availability The datasets used and/or analysed during the current study available from the corresponding author on reasonable request. Acknowledgements None Author contributions Yang Hu and Ming-cheng Du helped with the data curation. Yang Hu and Yi Chen helped with the software and formal analysis. Yang Hu, Ming-cheng Du, and Yi Chen helped with project administration. Xiang Long and Jing-jing Jiang helped with resources and investigation. Yuan Gong helped with the methodology, supervision, and validation. All authors have contributed equally to the manuscript and have read and approved the final version of the manuscript. Funding None. Competing interests The authors declare no competing interests. Prior presentations Not applicable. References Xu, B. et al . Primary and secondary postoperative hemorrhage in pediatric tonsillectomy. World J. Clin. Cases 9 , 1543–1553; 10.12998/wjcc.v9.i7.1543 (2021). Hawley, K. Tonsillectomy and Adenoidectomy in Children . JAMA Otolaryngol. Head Neck Surg. 145 , 300; 10.1001/jamaoto.2018.3703 (2019). Kermode, J., Walker, S. & Webb, I. Postoperative vomiting in children . Anaesth. Intensive Care 23 , 196–199; 10.1177/0310057X9502300213 (1995). Gan, T. J. et al . Fourth consensus guidelines for the management of postoperative nausea and vomiting. Anesth. Analg. 131 , 411–448; 10.1213/ANE.0000000000004833 (2020). Estebe, J. P. Intravenous lidocaine. Best Pract. Res. Clin. Anaesthesiol. 31 , 513–521; 10.1016/j.bpa.2017.05.005 (2017). Echevarría, G. C. et al . Intra-operative lidocaine in the prevention of vomiting after elective tonsillectomy in children: A randomised controlled trial. Eur. J. Anaesthesiol. 35 , 343–348; 10.1097/EJA.0000000000000807 (2018). Nakajima, D., Kawakami, H., Mihara, T., Sato, H. & Goto, T. Effectiveness of intravenous lidocaine in preventing postoperative nausea and vomiting in pediatric patients: a systematic review and meta-analysis. PLoS One 15 , e0227904; 10.1371/journal.pone.0227904 (2020). Büttner, W. & Finke, W. Analysis of behavioural and physiological parameters for the assessment of postoperative analgesic demand in newborns, infants, and young children: a comprehensive report on seven consecutive studies. Paediatr. Anaesth. 10 , 303–318; 10.1046/j.1460-9592.2000.00530.x (2000). Czarnetzki, C. et al . Dexamethasone and risk of nausea and vomiting and postoperative bleeding after tonsillectomy in children: a randomized trial. JAMA 300 , 2621–2630; 10.1001/jama.2008.794 (2008). Tricco, A. C. et al . Interventions to decrease the risk of adverse cardiac events for patients receiving chemotherapy and serotonin (5-HT3) receptor antagonists: a systematic review. BMC Pharmacol. Toxicol. 16 , 1; 10.1186/2050-6511-16-1 (2015). Ochs, H. R., Knüchel, M., Abernethy, D. R. & Greenblatt, D. J. Dose-independent pharmacokinetics of intravenous lidocaine in humans. J. Clin. Pharmacol. 23 , 186–188; 10.1002/j.1552-4604.1983.tb02723.x (1983). Additional Declarations No competing interests reported. Cite Share Download PDF Status: Published Journal Publication published 26 Aug, 2024 Read the published version in Scientific Reports → Version 1 posted Editorial decision: Revision requested 07 Jun, 2024 Reviews received at journal 06 Jun, 2024 Reviewers agreed at journal 04 Jun, 2024 Reviews received at journal 01 Jun, 2024 Reviewers agreed at journal 01 Jun, 2024 Reviewers invited by journal 31 May, 2024 Editor assigned by journal 31 May, 2024 Editor invited by journal 30 May, 2024 Submission checks completed at journal 29 May, 2024 First submitted to journal 24 May, 2024 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. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. 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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-4474829","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":311613158,"identity":"1f91c162-77c1-404a-857f-e9f1f85a73de","order_by":0,"name":"Yang Hu","email":"","orcid":"","institution":"Yichang Central People's Hospital","correspondingAuthor":false,"prefix":"","firstName":"Yang","middleName":"","lastName":"Hu","suffix":""},{"id":311613159,"identity":"87a6727d-2424-4979-83e9-1f9f192dad47","order_by":1,"name":"Ming-cheng Du","email":"","orcid":"","institution":"China Three Gorges University \u0026 Yichang Central People’s 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19:23:51","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":68037,"visible":true,"origin":"","legend":"\u003cp\u003eLidocaine reduces the requirement for rescue analgesics\u003c/p\u003e","description":"","filename":"FIG2forPONV.png","url":"https://assets-eu.researchsquare.com/files/rs-4474829/v1/569bea1946da60ffd05638e3.png"},{"id":63821156,"identity":"2c946adb-7512-4fb6-9efa-38630d3db8c0","added_by":"auto","created_at":"2024-09-02 16:12:37","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":420574,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-4474829/v1/3b2bf087-63ed-40d7-bcbc-ed33c6626728.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Lidocaine and risk of postoperative vomiting in children undergoing tonsillectomy: a randomised clinical trial","fulltext":[{"header":"Introduction","content":"\u003cp\u003eTonsillectomy is the most common procedure for the treatment of paediatric recurrent acute tonsillitis and tonsillar enlargement.\u003csup\u003e1\u0026nbsp;\u003c/sup\u003eEven though the surgery is safe, common complications include postoperative nausea and vomiting (PONV), throat pain, and bleeding.\u003csup\u003e2\u003c/sup\u003e Children (\u0026ge;3 years) are at a high risk of PONV, which is the most common cause of dissatisfaction in children and their parents and prolongs hospitalisation.\u003csup\u003e3\u003c/sup\u003e\u003csup\u003e,4\u003c/sup\u003e\u003csup\u003e\u0026nbsp;\u003c/sup\u003eNumerous interventions have been recommended\u0026nbsp;to decrease the incidence of PONV,\u0026nbsp;especially dexamethasone, a 5-HT3 receptor antagonist.\u003csup\u003e4\u003c/sup\u003e However, the optimal management of PONV remains a challenge for clinical anaesthesiologists owing to the need\u0026nbsp;to balance the benefit of PONV intervention with the risk of adverse effects.\u003c/p\u003e\n\u003cp\u003eLidocaine has analgesic, antihyperalgesic, and anti-inflammatory properties, making it a general anaesthetic adjuvant.\u003csup\u003e5\u003c/sup\u003e Intravenous lidocaine has\u0026nbsp;antiemetic\u0026nbsp;properties in paediatric patients in combination with other antiemetics.\u003csup\u003e6,7\u003c/sup\u003e The mechanism of lidocaine to reduce PONV is unclear but might be due to the opioid-sparing effect. However, the effect of intravenous lidocaine solely for the prevention of PONV in paediatric tonsillectomy remains unclear. Therefore, we hypothesised that intravenous lidocaine solely may decrease the risk of PONV in a dose-dependent manner in children undergoing tonsillectomy (with or without adenoidectomy) without severe side effects. Owing to the difficulty in assessing nausea in paediatric patients, our trial focused solely on evaluating postoperative vomiting (POV). The selection of POV as the primary outcome was guided by the need for clinically meaningful outcomes with potential benefits.\u003c/p\u003e"},{"header":"Materials and methods ","content":"\u003cp\u003e\u003cem\u003eStudy design\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eThis was a single-centre, parallel-group, randomised, double-blind controlled trial. Ethical approvance was obtained from the Institutional Review Board of Yichang Central People\u0026rsquo;s Hospital (HEC-KYJJ-2020-038-02) and registered at www.chictr.org.cn (ChiCTR2100053006). The trial was conducted in compliance with the tenets of the Declaration of Helsinki and was registered on 8 November 2021. The study was conducted from 1 December 2021 to 1 March 2022 at Yichang Central People\u0026rsquo;s Hospital. Written informed consent was obtained from the parents of each child.\u003c/p\u003e\n\u003cp\u003eThe patients were randomised in a 1:1 ratio to each group. Randomisation was computer-generated, and each patient was assigned a code.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cem\u003ePatients\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003ePatients aged 3\u0026ndash;12 years (American Society of Anesthesiologists grade\u0026nbsp;I\u0026ndash;II) scheduled for elective tonsillectomy (with\u0026nbsp;or without\u0026nbsp;adenoidectomy) were enrolled. The children were divided into four groups: A (0 mg kg\u003csup\u003e-1\u003c/sup\u003e lidocaine), B (1 mg kg\u003csup\u003e-1\u003c/sup\u003e lidocaine), C (1.5 mg kg\u003csup\u003e-1\u003c/sup\u003e lidocaine), and D (2 mg kg\u003csup\u003e-1\u003c/sup\u003e lidocaine) (Anhui Changjiang Pharmaceutical Co. Ltd, Wuhu, China). The exclusion criteria were as follows: chronic cough, history of steroid or bronchodilator treatment, respiratory tract reactive disease, upper airway infection in the previous 2 weeks, therapy with angiotensin-converting enzyme inhibitors, gastroesophageal reflux, morbid obesity, known allergy to any of the study drugs, and use of medications and nutraceuticals known to affect blood pressure (BP) and heart rate (HR).\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cem\u003ePerioperative anaesthetic care\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003ePreoperatively, all children fasted\u0026nbsp;for 6\u0026nbsp;h and were restricted from oral intake of clear fluids for 1 h. The children entered the operating room with their parents\u0026nbsp;to curb their separation anxiety. Noninvasive BP, HR, electrocardiography, and pulse oxygen saturation were measured using a multifunction monitor (GE Healthcare, Helsinki, Finland). The width of\u0026nbsp;the BP cuff for each patient was\u0026nbsp;approximately two-thirds of the upper arm length. After 5 min of stabilisation,\u0026nbsp;the baseline\u0026nbsp;HR, systolic BP, diastolic BP, and mean arterial pressure values were obtained from the average of three measurements taken 2 min apart. A 22-gauge intravenous catheter was subsequently inserted into the veins at the back of the hand.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eAfter preoxygenation, the respective treatments were injected over\u0026nbsp;a 3-s period.\u0026nbsp;An anaesthetic nurse who had prepared the study treatments was blinded to the study and administered the injection with pump activation. Two minutes after the injection, general anaesthesia was induced following the induction protocol: sufentanil (Yichang Renfu Pharmaceutical Co. Ltd., Yichang, China) 0.25 \u0026mu;g kg\u003csup\u003e-1\u003c/sup\u003e, propofol (Fresenius Kabi Deutschland GmbH, Homburg, Germany) 2.0\u0026nbsp;mg kg\u003csup\u003e-1\u003c/sup\u003e, and suxamethonium chloride (Xi\u0026rsquo;an Hanfeng Pharmaceutical Co. Ltd., Xi\u0026rsquo;an, China) 1\u0026nbsp;mg kg\u003csup\u003e1\u003c/sup\u003e. When eyelash reflexes were absent, the patient was ventilated via a facemask with 100%\u0026nbsp;oxygen.\u0026nbsp;A cuffed endotracheal tube was used, the size of which was selected based on\u0026nbsp;a widely used formula (3.5 + age in years/4). Patients were excluded from the study if any difficulty was encountered during facemask ventilation. After intubation, rocuronium (Zhejiang Xianju Pharmaceutical Co. Ltd., Taizhou, China) 0.3\u0026nbsp;mg kg\u003csup\u003e-1\u003c/sup\u003e was injected to maintain muscle relaxation. Anaesthesia was maintained with 2%\u0026ndash;3% sevoflurane (Maruishi Pharmaceutical Co., Ltd., Osaka, Japan) and 50% medical air in oxygen.\u003c/p\u003e\n\u003cp\u003eThe surgery was performed by an experienced surgeon. At the end of the operation, sevoflurane was discontinued, and neostigmine (Zhejiang Xianju Pharmaceutical Co. Ltd., Taizhou, China)\u0026nbsp;0.04 mg kg\u003csup\u003e-1\u003c/sup\u003e and atropine (Suicheng Pharmaceutical Co. Ltd., Xinzheng, China) 0.02 mg kg\u003csup\u003e-1\u003c/sup\u003e were administered to antagonise any residual neuromuscular blockade. After extubation, an anaesthesiologist who was not involved in the study performed anaesthesia emergence and subsequently graded cough response. Following the completion of the surgery, oral suction was performed immediately after removing the endotracheal tube. Extubation was performed by confirming adequate tidal volume, regular spontaneous respiratory pattern, and purposeful behaviour (eyes open upon request). After extubation, the children were monitored for at least 5 min to resume regular spontaneous respiration and subsequently transferred to the postanaesthesia care unit (PACU). Electrocardiography, peripheral pulse oximetry, and noninvasive BP measurements were performed.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003ePatients were discharged from\u0026nbsp;the PACU to the ward when their\u0026nbsp;Steward recovery score was higher than 4, where they stayed overnight. Other perioperative care was performed according to the practices of\u0026nbsp;local clinicians.\u0026nbsp;If the rating score for pain was \u0026ge;3 at rest, as assessed by the Children and Infants Postoperative Pain Scale,\u003csup\u003e8\u003c/sup\u003e intravenous propacetamol 30 mg kg\u003csup\u003e-1\u003c/sup\u003e was administered by the attending PACU nurse. \u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cem\u003ePrimary outcomes\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eThe primary outcome was the incidence of POV within 24 h postoperatively. Rescue methods for POV were intravenous ondansetron 50\u0026nbsp;\u0026mu;g kg\u003csup\u003e-1\u003c/sup\u003e and dexamethasone 0.1 mg kg\u003csup\u003e-1\u003c/sup\u003e.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eSecondary outcomes\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eSecondary outcomes were evaluated to determine the analgesic efficacy of lidocaine. The incidence of children requiring analgesic rescue within 24 h was recorded. Adverse events included laryngospasm, oxygen desaturation, upper airway obstruction, and arrhythmia.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eStatistical analysis\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eAssuming\u0026nbsp;a 55% rate of PONV\u003csup\u003e5\u003c/sup\u003e (55% for the primary outcome), we found that a sample size of 50 patients would be required to achieve 95% power at a two-sided \u0026alpha; level of 0.05 to demonstrate a relative between-group difference of 55% in the composite primary outcome measure (55% to 14%). Patient characteristics (including age, height,\u0026nbsp;and weight),\u0026nbsp;time of surgery,\u0026nbsp;and\u0026nbsp;time to extubation were expressed as means and standard deviations and were analysed using analysis of variance. The incidence of PONV and consumption of analgesics were expressed as\u0026nbsp;a ratio and analysed using \u0026chi;\u003csup\u003e2\u003c/sup\u003e, with a \u003cem\u003eP\u0026nbsp;\u003c/em\u003evalue \u0026lt;.05 indicating a difference. Statistical significance was set at \u003cem\u003eP\u003c/em\u003e\u0026lt;.01 for all analyses. GraphPad Prism 8.0.2 (GraphPad Software Inc., San Diego, CA, USA) was used for all analyses.\u003c/p\u003e"},{"header":"Results","content":"\u003cp\u003e\u003cem\u003ePatients\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eBetween 1 December 2021 and 1 March 2022, 280 patients were enrolled in the study, of whom 200 were included in the analysis and divided into four groups; the demographic characteristics and operative data did not differ between the groups (Table 1).\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cem\u003ePrimary outcomes\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eThe incidence of POV\u0026nbsp;was 46% (95% confidence interval [CI]: 32%\u0026ndash;61%), 40% (95% CI: 26%\u0026ndash;55%), 36% (95% CI: 23%\u0026ndash;51%), and 20% (95% CI: 10%\u0026ndash;34%) in groups A, B, C, and D, respectively. There was\u0026nbsp;a\u0026nbsp;significant difference between groups D and A (\u003cem\u003eP\u003c/em\u003e\u0026le;.01), with a dose-dependent decrease in POV (Fig. 1). \u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eSecondary outcomes\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eThe incidence of postoperative analgesic rescue in groups A, B, C, and D was\u0026nbsp;62% (95% CI, 47%\u0026ndash;75%), 36% (95% CI, 23%\u0026ndash;51%), 34% (95% CI, 21%\u0026ndash;49%), and 16% (95% CI, 7%\u0026ndash;29%),\u0026nbsp;respectively. Significant differences were\u0026nbsp;observed between\u0026nbsp;groups D and B and groups C\u0026nbsp;and A (\u003cem\u003eP\u003c/em\u003e\u0026le;.01) and between groups D and A\u0026nbsp;(\u003cem\u003eP\u003c/em\u003e\u0026le;.001) (Fig. 2). There were no significant differences among the groups in the time to extubation, even when this difference was extended to 2 min longer than that in group A (Table 1). Moreover, no severe complications, such as postoperative hypoxaemia, laryngospasm, or arrhythmia, were observed in any group.\u003c/p\u003e\n\u003cp\u003eTable 1. Patient characteristics and clinical data\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd width=\"21.062618595825427%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.734345351043643%\" valign=\"top\"\u003e\n \u003cp\u003eGroup A\u003c/p\u003e\n \u003cp\u003e(n=50)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.734345351043643%\" valign=\"top\"\u003e\n \u003cp\u003eGroup B\u003c/p\u003e\n \u003cp\u003e(n=50)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.734345351043643%\" valign=\"top\"\u003e\n \u003cp\u003eGroup C\u003c/p\u003e\n \u003cp\u003e(n=50)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.734345351043643%\" valign=\"top\"\u003e\n \u003cp\u003eGroup D\u003c/p\u003e\n \u003cp\u003e(n=50)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"21.062618595825427%\"\u003e\n \u003cp\u003eAge (years)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.734345351043643%\"\u003e\n \u003cp\u003e5.78\u0026plusmn;2.04\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.734345351043643%\"\u003e\n \u003cp\u003e6.05\u0026plusmn;2.09\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.734345351043643%\"\u003e\n \u003cp\u003e5.63\u0026plusmn;1.92\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.734345351043643%\"\u003e\n \u003cp\u003e6.13\u0026plusmn;1.92\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"21.062618595825427%\"\u003e\n \u003cp\u003eHeight (cm)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.734345351043643%\"\u003e\n \u003cp\u003e120.00\u0026plusmn;14.68\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.734345351043643%\"\u003e\n \u003cp\u003e118.23\u0026plusmn;23.46\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.734345351043643%\"\u003e\n \u003cp\u003e117.08\u0026plusmn;12.04\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.734345351043643%\"\u003e\n \u003cp\u003e121.50\u0026plusmn;13.47\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"21.062618595825427%\"\u003e\n \u003cp\u003eWeight (kg)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.734345351043643%\"\u003e\n \u003cp\u003e23.95\u0026plusmn;7.72\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.734345351043643%\"\u003e\n \u003cp\u003e23.61\u0026plusmn;7.69\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.734345351043643%\"\u003e\n \u003cp\u003e22.59\u0026plusmn;7.11\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.734345351043643%\"\u003e\n \u003cp\u003e25.99\u0026plusmn;8.23\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"21.062618595825427%\"\u003e\n \u003cp\u003eSex (M\u0026frasl; F)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.734345351043643%\"\u003e\n \u003cp\u003e23/22\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.734345351043643%\"\u003e\n \u003cp\u003e27/18\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.734345351043643%\"\u003e\n \u003cp\u003e25/20\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.734345351043643%\"\u003e\n \u003cp\u003e28/17\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"21.062618595825427%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.734345351043643%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.734345351043643%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.734345351043643%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.734345351043643%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"21.062618595825427%\"\u003e\n \u003cp\u003eTime\u0026nbsp;of operation (min)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.734345351043643%\"\u003e\n \u003cp\u003e30.18\u0026plusmn;11.87\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.734345351043643%\"\u003e\n \u003cp\u003e29.82\u0026plusmn;11.78\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.734345351043643%\"\u003e\n \u003cp\u003e31.31\u0026plusmn;14.14\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.734345351043643%\"\u003e\n \u003cp\u003e27.15\u0026plusmn;11.89\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"21.062618595825427%\"\u003e\n \u003cp\u003eTime of extubation (min)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.734345351043643%\"\u003e\n \u003cp\u003e11.69\u0026plusmn;3.60\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.734345351043643%\"\u003e\n \u003cp\u003e13.80\u0026plusmn;3.47\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.734345351043643%\"\u003e\n \u003cp\u003e13.38\u0026plusmn;3.89\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.734345351043643%\"\u003e\n \u003cp\u003e13.33\u0026plusmn;3.66\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"21.062618595825427%\"\u003e\n \u003cp\u003eIncidence of laryngospasm\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.734345351043643%\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.734345351043643%\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.734345351043643%\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.734345351043643%\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"21.062618595825427%\"\u003e\n \u003cp\u003eIncidence of postoperative hypoxemia\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.734345351043643%\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.734345351043643%\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.734345351043643%\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.734345351043643%\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"21.062618595825427%\"\u003e\n \u003cp\u003eIncidence of arrhythmia\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.734345351043643%\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.734345351043643%\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.734345351043643%\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.734345351043643%\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"21.062618595825427%\"\u003e\n \u003cp\u003eAdenotonsillectomy with/without tonsillectomy\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.734345351043643%\"\u003e\n \u003cp\u003e43/2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.734345351043643%\"\u003e\n \u003cp\u003e45/0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.734345351043643%\"\u003e\n \u003cp\u003e45/0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.734345351043643%\"\u003e\n \u003cp\u003e44/1\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eValues are expressed as the mean\u0026plusmn;standard deviation or number. \u0026dagger;P \u0026lt; 0.05 vs. Group A. ASA, American Society of Anesthesiologists\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eGroup A, lidocaine 0 mg kg\u003csup\u003e-1\u003c/sup\u003e IV; group B, lidocaine 1 mg kg\u003csup\u003e-1\u003c/sup\u003e IV; group C, lidocaine 1.5 mg kg\u003csup\u003e-1\u003c/sup\u003e IV; and group D, lidocaine 2 mg kg\u003csup\u003e-1\u003c/sup\u003e IV.\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eThe 2020 consensus guidelines for the management of\u0026nbsp;PONV recommend 5-HT3 antagonists and dexamethasone (0.15 mg kg\u003csup\u003e-1\u003c/sup\u003e) as the standard prophylaxis.\u003csup\u003e4\u003c/sup\u003e Dexamethasone is an efficacious antiemetic but is associated with a risk of postoperative bleeding, which is sometimes fatal.\u003csup\u003e9\u003c/sup\u003e 5-HT\u003csub\u003e3\u003c/sub\u003e receptor antagonists are commonly\u0026nbsp;used in PONV management\u0026nbsp;and may cause adverse cardiac events, such as arrhythmia.\u003csup\u003e10\u003c/sup\u003e Our results showed that intravenous lidocaine effectively and dose-dependently reduced\u0026nbsp;the incidence of POV in\u0026nbsp;children undergoing tonsillectomy (with or without adenoidectomy) without severe side effects. Only\u0026nbsp;2 mg kg\u003csup\u003e-1\u003c/sup\u003e lidocaine achieved a significantly better clinical effect (20%).\u003c/p\u003e\n\u003cp\u003eSignificantly fewer\u0026nbsp;children received rescue analgesics in each group during the first 24 h. Significant differences were\u0026nbsp;observed between\u0026nbsp;groups D and B, groups C\u0026nbsp;and A (\u003cem\u003eP\u003c/em\u003e\u0026le;.01), and groups D and A\u0026nbsp;(\u003cem\u003eP\u003c/em\u003e\u0026le;.001). The reduction in rescue analgesic requirement may not be explained by the analgesic effect of lidocaine\u0026nbsp;because the half-life of lidocaine is 2 h.\u003csup\u003e11\u0026nbsp;\u003c/sup\u003eThe mechanism underlying this phenomenon remains unclear and\u0026nbsp;may be associated with the anti-inflammatory effects of intravenous lidocaine.\u003c/p\u003e\n\u003cp\u003eOur trial first found that the single dose of lidocaine needed to achieve an antiemetic effect was higher than that needed to achieve an analgesic effect within 24 h postoperatively. This is due to the multi-model anaesthesia and opioid-sparing effect of lidocaine. There were no significant differences\u0026nbsp;in\u0026nbsp;the clinical characteristics and clinical data between\u0026nbsp;the groups.\u0026nbsp;No severe side effects were observed in this trial. However, in our study, the time of extubation in\u0026nbsp;the groups administered intravenous lidocaine was prolonged by nearly 2 min, which is different from that in other studies.\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;Our study has certain limitations. First,\u0026nbsp;we chose a single dose of lidocaine for the advent of lidocaine accumulation.\u0026nbsp;Second, this was\u0026nbsp;a single-centre\u0026nbsp;study, which\u0026nbsp;reduced the power and reliability of the results. Third, we used the concentration of sevoflurane in the\u0026nbsp;end-expiratory gas\u0026nbsp;to monitor the depth of anaesthesia,\u0026nbsp;potentially leading to an increased\u0026nbsp;incidence of POV.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eIn conclusion, our study revealed that intravenous lidocaine solely decreased the incidence of PONV in children undergoing tonsillectomy (with or without adenoidectomy) in a dose-dependent manner.\u0026nbsp;No serious adverse events were observed\u0026nbsp;after the administration of different doses of\u0026nbsp;intravenous\u0026nbsp;lidocaine.\u0026nbsp;\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eData availability\u003c/strong\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eThe datasets used and/or analysed during the current study available from the corresponding author on reasonable request.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAcknowledgements\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNone\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthor contributions\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eYang Hu and Ming-cheng Du helped with the data curation. Yang Hu and Yi Chen helped with the software and formal analysis. Yang Hu, Ming-cheng Du, and Yi Chen helped with project administration. Xiang Long and Jing-jing Jiang helped with resources and investigation. Yuan Gong helped with the methodology, supervision, and validation. All authors have contributed equally to the manuscript and have read and approved the final version of the manuscript.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNone.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting interests\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors declare no competing interests.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003ePrior presentations\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNot applicable.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eXu, B. \u003cem\u003eet al\u003c/em\u003e. Primary and secondary postoperative hemorrhage in pediatric tonsillectomy. \u003cem\u003eWorld J. Clin. Cases\u003c/em\u003e \u003cstrong\u003e9\u003c/strong\u003e, 1543\u0026ndash;1553; 10.12998/wjcc.v9.i7.1543 (2021). \u003c/li\u003e\n\u003cli\u003eHawley, K. Tonsillectomy and Adenoidectomy in Children\u003cem\u003e. JAMA Otolaryngol. Head Neck Surg.\u003c/em\u003e \u003cstrong\u003e145\u003c/strong\u003e, 300; 10.1001/jamaoto.2018.3703 (2019).\u003c/li\u003e\n\u003cli\u003eKermode, J., Walker, S. \u0026amp; Webb, I. Postoperative vomiting in children\u003cem\u003e. Anaesth. Intensive Care\u003c/em\u003e \u003cstrong\u003e23\u003c/strong\u003e, 196\u0026ndash;199; 10.1177/0310057X9502300213 (1995).\u003c/li\u003e\n\u003cli\u003eGan, T. J. \u003cem\u003eet al\u003c/em\u003e. Fourth consensus guidelines for the management of postoperative nausea and vomiting. \u003cem\u003eAnesth. Analg.\u003c/em\u003e \u003cstrong\u003e131\u003c/strong\u003e, 411\u0026ndash;448; 10.1213/ANE.0000000000004833 (2020).\u003c/li\u003e\n\u003cli\u003eEstebe, J. P. Intravenous lidocaine. \u003cem\u003eBest Pract. Res. Clin. Anaesthesiol.\u003c/em\u003e \u003cstrong\u003e31\u003c/strong\u003e, 513\u0026ndash;521; 10.1016/j.bpa.2017.05.005 (2017). \u003c/li\u003e\n\u003cli\u003eEchevarr\u0026iacute;a, G. C. \u003cem\u003eet al\u003c/em\u003e. Intra-operative lidocaine in the prevention of vomiting after elective tonsillectomy in children: A randomised controlled trial. \u003cem\u003eEur. J. Anaesthesiol.\u003c/em\u003e \u003cstrong\u003e35\u003c/strong\u003e, 343\u0026ndash;348; 10.1097/EJA.0000000000000807 (2018). \u003c/li\u003e\n\u003cli\u003eNakajima, D., Kawakami, H., Mihara, T., Sato, H. \u0026amp; Goto, T. Effectiveness of intravenous lidocaine in preventing postoperative nausea and vomiting in pediatric patients: a systematic review and meta-analysis. \u003cem\u003ePLoS One\u003c/em\u003e \u003cstrong\u003e15\u003c/strong\u003e, e0227904; 10.1371/journal.pone.0227904 (2020).\u003c/li\u003e\n\u003cli\u003eB\u0026uuml;ttner, W. \u0026amp; Finke, W. Analysis of behavioural and physiological parameters for the assessment of postoperative analgesic demand in newborns, infants, and young children: a comprehensive report on seven consecutive studies. \u003cem\u003ePaediatr. Anaesth. \u003c/em\u003e\u003cstrong\u003e10\u003c/strong\u003e, 303\u0026ndash;318; 10.1046/j.1460-9592.2000.00530.x (2000).\u003c/li\u003e\n\u003cli\u003eCzarnetzki, C. \u003cem\u003eet al\u003c/em\u003e. Dexamethasone and risk of nausea and vomiting and postoperative bleeding after tonsillectomy in children: a randomized trial. \u003cem\u003eJAMA\u003c/em\u003e \u003cstrong\u003e300\u003c/strong\u003e, 2621\u0026ndash;2630; 10.1001/jama.2008.794 (2008). \u003c/li\u003e\n\u003cli\u003eTricco, A. C. \u003cem\u003eet al\u003c/em\u003e. Interventions to decrease the risk of adverse cardiac events for patients receiving chemotherapy and serotonin (5-HT3) receptor antagonists: a systematic review. \u003cem\u003eBMC Pharmacol. Toxicol.\u003c/em\u003e \u003cstrong\u003e16\u003c/strong\u003e, 1; 10.1186/2050-6511-16-1 (2015). \u003c/li\u003e\n\u003cli\u003eOchs, H. R., Kn\u0026uuml;chel, M., Abernethy, D. R. \u0026amp; Greenblatt, D. J. Dose-independent pharmacokinetics of intravenous lidocaine in humans. \u003cem\u003eJ. Clin. Pharmacol.\u003c/em\u003e \u003cstrong\u003e23\u003c/strong\u003e, 186\u0026ndash;188; 10.1002/j.1552-4604.1983.tb02723.x (1983).\u003c/li\u003e\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":"scientific-reports","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"scirep","sideBox":"Learn more about [Scientific Reports](http://www.nature.com/srep/)","snPcode":"","submissionUrl":"","title":"Scientific Reports","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Scientific Reports","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"lidocaine, Postoperative vomiting, Tonsillectomy","lastPublishedDoi":"10.21203/rs.3.rs-4474829/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-4474829/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eThe dose-response of intravenous lidocaine for preventing postoperative vomiting (POV) in children is unclear. This study investigated whether intravenous lidocaine dose-dependently decreases POV risk within 24 h postoperatively in children undergoing tonsillectomy (with/without adenoidectomy) without severe complications. Patients aged 3–12 years (American Society of Anesthesiologists grade I–II) scheduled for elective tonsillectomy (with/without adenoidectomy) were enrolled from December 2021 to March 2022. They were randomly grouped according to the lidocaine dose (A [0 mg kg\u003csup\u003e-1\u003c/sup\u003e], B [1 mg kg\u003csup\u003e-1\u003c/sup\u003e], C [1.5 mg kg\u003csup\u003e-1\u003c/sup\u003e], and D [2 mg kg\u003csup\u003e-1\u003c/sup\u003e]) and were administered the same induction protocol (sufentanil, propofol, and suxamethonium chloride). Anaesthesia was maintained using sevoflurane. POV incidence within 24 h postoperatively was 46%, 40%, 36%, and 20% in groups A, B, C, and D, respectively, with significant differences between groups D and A. That of postoperative analgesic rescue in groups A, B, C, and D was 62%, 36%, 34%, and 16%, respectively, with significant differences between groups D and B, C and A, and D and A. No severe adverse events occurred. Intravenous lidocaine (2 mg kg\u003csup\u003e-1\u003c/sup\u003e) dose-dependently decreases POV risk without serious adverse events in children undergoing tonsillectomy (with/without adenoidectomy).\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eTrial registration: Chinese Clinical Trial Registry,\u003cstrong\u003e \u003c/strong\u003eChiCTR2100053006.\u003c/p\u003e","manuscriptTitle":"Lidocaine and risk of postoperative vomiting in children undergoing tonsillectomy: a randomised clinical trial","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-06-12 19:23:47","doi":"10.21203/rs.3.rs-4474829/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2024-06-07T05:36:15+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2024-06-06T05:13:04+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"126947631462376150700328332772700349617","date":"2024-06-04T16:45:31+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2024-06-01T22:43:12+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"124066401716050991291296684851272366637","date":"2024-06-01T08:49:23+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2024-05-31T05:31:35+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2024-05-31T04:49:35+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"","date":"2024-05-30T19:08:37+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2024-05-29T09:37:05+00:00","index":"","fulltext":""},{"type":"submitted","content":"Scientific Reports","date":"2024-05-25T02:29:15+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"scientific-reports","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"scirep","sideBox":"Learn more about [Scientific Reports](http://www.nature.com/srep/)","snPcode":"","submissionUrl":"","title":"Scientific Reports","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Scientific Reports","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"cca56e05-fb19-4f8f-bf87-828f3bbb5202","owner":[],"postedDate":"June 12th, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[{"id":32934479,"name":"Biological sciences/Drug discovery/Pharmacology"},{"id":32934480,"name":"Health sciences/Medical research"}],"tags":[],"updatedAt":"2024-09-02T16:05:41+00:00","versionOfRecord":{"articleIdentity":"rs-4474829","link":"https://doi.org/10.1038/s41598-024-70804-w","journal":{"identity":"scientific-reports","isVorOnly":false,"title":"Scientific Reports"},"publishedOn":"2024-08-26 15:58:15","publishedOnDateReadable":"August 26th, 2024"},"versionCreatedAt":"2024-06-12 19:23:47","video":"","vorDoi":"10.1038/s41598-024-70804-w","vorDoiUrl":"https://doi.org/10.1038/s41598-024-70804-w","workflowStages":[]},"version":"v1","identity":"rs-4474829","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-4474829","identity":"rs-4474829","version":["v1"]},"buildId":"qtupq5eGEP_6zYnWcrvyt","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}