Management of Status Asthmaticus with Sevoflurane in the ICU: case report

Management of Status Asthmaticus with Sevoflurane in the ICU: case report | 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 Case Report Management of Status Asthmaticus with Sevoflurane in the ICU: case report Alexis Stephano Henales Ocampo, Orlando Rubén Pérez Nieto, Carlos Mendiola-Villalobos, and 3 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6805022/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract This case report describes a 66-year-old female patient with a 20-year history of asthma and type 2 diabetes mellitus, who was admitted for scheduled extracapsular cataract extraction. During recovery, she developed status asthmaticus, characterized by severe dyspnea, hypoxemia, and increased respiratory effort. Initial management included bronchodilators, systemic corticosteroids, and ketamine, but the patient remained unresponsive. The introduction of sevoflurane provided significant bronchodilatory effects, contributing to stabilization and early extubation. This case underscores the importance of timely interventions and the potential role of sevoflurane in managing refractory asthma exacerbations. Anesthesiology & Pain Medicine Critical Care & Emergency Medicine Status asthmaticus sevoflurane mechanical ventilation asthma exacerbation Figures Figure 1 Figure 2 BACKGROUND Status asthmaticus in adults represents a critical exacerbation of asthma, marked by unresponsive bronchospasm and respiratory failure. This condition necessitates hospitalization and is associated with high rates of intensive care unit (ICU) admissions. Mortality rates can reach 1–4%, influenced by underlying comorbidities and the timeliness of intervention ( 1 , 2 ). Effective management typically includes bronchodilators, systemic corticosteroids, and, in severe instances, mechanical ventilation ( 3 ). Raising awareness and implementing early interventions are essential to reduce complications and improve patient outcomes ( 4 ). Mechanism of Action of Sevoflurane in Status Asthmaticus Sevoflurane plays a crucial role in the management of status asthmaticus due to its potent bronchodilatory properties. It reduces airway resistance by inhibiting voltage-gated calcium channels, which decreases intracellular calcium levels and relaxes bronchial smooth muscle ( 5 ). Additionally, sevoflurane interacts with GABAergic and glycinergic pathways, lowering airway reactivity and stabilizing respiratory function ( 6 ). Furthermore, it suppresses the release of inflammatory mediators, helping to alleviate airway hyperresponsiveness ( 7 , 8 ). By dampening vagal nerve-mediated bronchoconstriction, sevoflurane provides benefits for patients who do not respond to conventional therapies ( 9 ). This case report was based on the CARE guidelines for case reporting. Informed consent was obtained from the patient for the publication of the case. CASE REPORT A 66-year-old female with a 20-year history of asthma, managed occasionally with salbutamol spray, and type 2 diabetes mellitus for 5 years, managed with metformin, was admitted on 11/04/2024 for a scheduled extracapsular cataract extraction in the left eye. Medications administered included 400 mg of paracetamol, two doses of 25 mcg fentanyl, 4 mg of ondansetron, and local anesthesia with lidocaine for retrobulbar block, along with 50 ml of Hartmann's solution. The surgery lasted 35 minutes, and nasal cannulas were used throughout the procedure without any intraoperative incidents. The patient was transferred to the recovery room at 11:00 with the following vital signs: peripheral oxygen saturation (SpO₂) of 94% on nasal cannulas at 4 L/min, blood pressure (BP) of 121/88 mmHg, heart rate (HR) of 88 beats per minute, and no record of respiratory rate (RR). At 12:17 PM, the patient developed dyspnea and hypoxemia, with SpO₂ between 76% and 80%, HR of 103 bpm, BP of 161/93 mmHg, and audible wheezing. A face mask was applied to increase oxygen support; however, no improvement was observed, with SpO₂ dropping to 60%. Subsequently, 1 g of magnesium sulfate and 1 mg of epinephrine were administered. She was transferred to the operating room for 100% FiO₂ delivery using the anesthesia machine, during which she experienced cardiac arrest. Chest compressions were initiated, and orotracheal intubation was performed with a 6.5 F endotracheal tube. After a second cycle of compressions, spontaneous circulation returned. An arterial blood gas (ABG) test was performed at 12:50, revealing a partial arterial carbon dioxide pressure (PaCO₂) of 86 mmHg, pH of 7.03, partial arterial oxygen pressure (PaO₂) of 108 mmHg, lactate of 3.9 mmol/L, HCO₃ of 17.4, arterial oxygen saturation (SaO₂) of 95%, and a PaO₂/FiO₂ ratio of 108, indicating respiratory and metabolic acidosis. Hypoventilation and bilateral wheezing were noted, and three additional doses of 1 mg epinephrine were administered, along with two doses of 100 mg hydrocortisone, salbutamol sprays, and budesonide micronebulization. Oxygenation improved, with a new ABG test at 13:28 reporting PaCO₂ of 54 mmHg, pH of 7.21, lactate of 2.7 mmol/L, PaO₂ of 127 mmHg, SaO₂ of 98%, and a PaO₂/FiO₂ ratio of 254. The patient was extubated in the operating room but again developed hypoxemia and increased work of breathing (WOB). A laryngeal mask was placed for 30 minutes and later removed, after which an oxygen reservoir face mask was applied. She was admitted to the ICU with increased WOB, using sternocleidomastoid muscles and showing intense abdominal expiration, with wheezing in both hemithoraxes, stridor, a Glasgow Coma Scale (GCS) score of 14 points. High-intensity non-invasive ventilation (NIV) was initiated, with a pressure support (PS) aimed at achieving a tidal volume (Vt) of 10 ml/kg of predicted body weight, continuous positive airway pressure (CPAP) of 0 cmH₂O, flow trigger of 2 L/min, showing an obstructive flow pattern with peak expiratory flow (PEF) of 30 L/min. She was treated with salbutamol and ipratropium via vibrating mesh (Aerogen) and 50 mg IV ketamine, without improvement, leading to a loss of alertness and a silent chest and BP 96/59 mmHg. A decision was made for rapid sequence intubation, administering 100 mg/kg IV ketamine and 50 mg rocuronium, with intubation on the first attempt using a video laryngoscope and bougie, placing an 8 F tube without hypoxemia. An obstructive expiratory flow pattern was observed. The patient was placed on volume-controlled mode (AC-V) with an RR of 14 bpm, inspiratory flow of 40 L/min, Vt of 400 ml, PEEP of 0 cmH₂O, I:E ratio of 1:4, achieving complete exhalations, with measured autoPEEP of 0.8 cmH₂O, peak airway pressure (Paw) of 16 cmH₂O, resistive pressure of 6 cmH₂O, and plateau pressure (Pm) of 10 cmH₂O. Post-ventilatory management ABG test at 15:23 reported PaCO₂ of 54 mmHg, pH of 7.21, lactate of 2.7 mmol/L, PaO₂ of 127 mmHg, SaO₂ of 98%, and a PaO₂/FiO₂ ratio of 254. Continuous salbutamol and ipratropium nebulizations with vibrating mesh were administered for 2 hours, with wheezing persisting bilaterally; the RR was adjusted to 11 bpm, maintaining an I ratio of 1:4 for complete exhalations. Two hours later, Paw increased to 22 cmH₂O with a Pm increase to 12 cmH₂O and resistive pressure to 10 cmH₂O. Due to persistent bronchospasm and lack of improvement following conventional medical treatment, sevoflurane was administered via anaesthetic conserving device (ACD, Sedaconda), with an initial bolus of 1.5 ml, followed by a dose of 1.5 ml/h at 20:00 for 30 minutes. At 22:30, the dose was adjusted to 3 ml/h due to increased ventilatory effort and spontaneous RR of 24 bpm with a RASS of 3 points. At 23:30, the dose was raised to a maximum of 5 ml/h to maintain a mandatory RR of 11 bpm, Vt of 400 ml, I:E of 1:4.4, FiO₂ of 28%, and SpO₂ of 92–96%. The next day, at 03:30, during a new episode of severe bronchospasm with a silent right hemithorax and barely audible wheezing in the left hemithorax, the sevoflurane dose was increased to 5.5 ml/h, resulting in rapid improvement. At 06:00, the sevoflurane dose was gradually decreased to 4 ml/h, then to 3 ml/h at 07:00. The patient presented with spontaneous respirations and a RASS of 0 points. A spontaneous breathing trial (SBT) with PEEP of 0 cmH₂O, PS of 0 cmH₂O, and FiO₂ of 28% was positive, with no dyspnea, leading to successful removal from mechanical ventilation. High-flow nasal cannulas (HFNC) were applied with a flow rate of 20 L/min, FiO₂ of 40%, aiming for SpO₂ of 94% and air temperature of 37°C to prevent bronchial reactions to cold air. The family member was allowed in the room for observation. Post-extubation ABG revealed a PaCO₂ of 35 mmHg, pH of 7.44, PaO₂ of 88 mmHg, and lactate of 2.1 mmol/L. Salbutamol, ipratropium, and budesonide nebulizations with vibrating mesh were continued, and systemic corticosteroids were discontinued. The patient was discharged from the ICU the following day due to improvement, with treatment adjusted by the pulmonology department. DISCUSSION This case illustrates the complexities involved in managing status asthmaticus, a critical condition that demands immediate medical attention and often requires intensive care support. In this instance, the asthmatic crisis was refractory to the standard treatment regimen, which included short-acting beta-agonists, anticholinergics via vibrating mesh nebulization, systemic corticosteroids, and even ketamine—an option for patients unresponsive to conventional therapies ( 10 ). The use of sevoflurane in this scenario highlights its dual role as both an anesthetic and bronchodilator. Its mechanisms, including calcium channel inhibition and modulation of inflammatory responses, present a valuable therapeutic option when traditional treatments fail. A recent systematic review identified 18 case reports of sevoflurane used for status asthmaticus, revealing only one case of mortality among those receiving anesthesia during treatment ( 11 ). Despite the heterogeneity of these studies, sevoflurane emerges as a viable, safe, and likely effective option for patients who are refractory to conventional therapies. Another advantage of sevoflurane noted in this case was the rapid awakening associated with a reduction in the dose from 5 to 3 mL/h, facilitating an early weaning from mechanical ventilation. It is crucial to emphasize that the ventilatory management during invasive mechanical ventilation was aimed at preventing air trapping from the outset. A low respiratory rate and extended inspiratory-to-expiratory (I:E) ratios were employed to ensure complete exhalations, thereby avoiding dynamic hyperinflation ( 10 ). As the patient's ventilatory status improved, we conducted a spontaneous breathing trial with zero PEEP and pressure support, closely simulating the post-extubation mechanical state ( 12 ). In retrospect, we opted for high-flow nasal cannula (HFNC) support at 37°C following extubation, as we believe exposure to cold air and oxygen in the operating room may have triggered the asthmatic crisis. Therefore, we maintained relatively low FiO₂ and flow rates ( 14 ). Ultimately, this case underscores the need for vigilant monitoring and timely intervention to mitigate the risks associated with status asthmaticus. Early recognition and aggressive management are essential for improving outcomes in patients experiencing severe asthma exacerbations. Patient perspective The patient was interviewed in the afternoon following her extubation. She reported experiencing amnesia from the time of cannulation until she began to awaken for the spontaneous ventilation trial. The only discomfort she mentioned was a mild sore throat and slight difficulty breathing. She exhibited no signs of delirium and, although she had been with her sister since extubation, expressed a desire to see the rest of her family. Overall, she appeared calm and free of anxiety. CONCLUSION This case describes a severe asthma exacerbation triggered by a perioperative complication in a patient undergoing elective cataract surgery. Despite rapid progression to respiratory failure, hypoxemia, and bronchospasm unresponsive to conventional treatment, intensive measures—including mechanical ventilation, bronchodilator therapy, and volatile anesthetic administration—achieved gradual improvement. The patient’s condition stabilized with careful titration of sevoflurane and high-intensity non-invasive ventilation, allowing for successful extubation and discharge from the ICU. This case highlights the complexity of managing perioperative respiratory emergencies in patients with chronic asthma and the potential role of sevoflurane in refractory bronchospasm. Declarations Ethical Approval and Consent to participate: The consent and approval of the patient involved for publication for scientific purposes has been obtained in writing and signed; a copy of the consent is included in the appendices. Consent for publication: We have the consent for publication from the patient and the head of the intensive care unit involved for the case report. Availability of supporting data: We have all the data to support the events previously described in the case report. Competing interests: Not applicable Funding: Not applicable Authors' contributions Acknowledgements References Reddel HK, Bacharier LB, Bateman ED et al (2021) Global Initiative for Asthma Strategy 2021: GINA Update. Asthma Res Pract 7(1):1–9. 10.1186/s40733-021-00169-4 Beasley R, Crane J, Fletcher M et al (2021) Epidemiology of asthma: the global burden of asthma and its impact on quality of life. Eur Respir J 58(5):2001431. 10.1183/13993003.01431-2020 GINA. Global Strategy for Asthma Management and Prevention. Global Initiative for Asthma (2024) Available from: https://ginasthma.org/gina-reports/ Dyer AM, McKenzie S, Talbot E et al (2020) Trends in asthma morbidity and mortality in adults: a population-based cohort study. Thorax 75(5):441–448. 10.1136/thoraxjnl-2019-213200 Chang Y, Xia Y, Zhang S et al (2018) Effects of volatile anesthetics on bronchoconstriction in asthma: A systematic review and meta-analysis. Anesth Analg 126(2):523–528. 10.1213/ANE.0000000000002342 Ho GWK, Thaarun T, Ee NJ et al (2024) A systematic review on the use of sevoflurane in the management of status asthmaticus in adults. Crit Care 28:334. 10.1186/s13054-024-05122-8 Turner A, Wood-Baker R, Walters EH (2016) Use of inhalational anaesthetics for status asthmaticus in intensive care. Respir Med 115:17–20. 10.1016/j.rmed.2016.04.015 Watson P, Wall R, Browne K (2017) The effects of volatile anaesthetics in patients with severe asthma. Br J Anaesth 118(2):183–189. 10.1093/bja/aew443 Chuang CC, Lin SW, Chen KS et al (2019) Sevoflurane for refractory status asthmaticus in pediatric and adult patients: A systematic review. Int J Crit Illn Inj Sci 9(3):143–147. 10.4103/IJCIIS.IJCIIS_8_19 Garner O, Ramey JS, Hanania NA (2022) Management of life-threatening asthma: severe asthma series. Chest 162(4):747–756. 10.1016/j.chest.2022.02.029 Ho GWK, Thaarun T, Ee NJ et al (2024) A systematic review on the use of sevoflurane in the management of status asthmaticus in adults. Crit Care 28:334. https://doi.org/10.1186/s13054-024-05122-8 Capdevila M, Aarab Y, Monet C et al (2024) Spontaneous breathing trials should be adapted for each patient according to the critical illness. A new individualised approach: the GLOBAL WEAN study. Intensive Care Med. https://doi.org/10.1007/s00134-024-07657-4 Hashmi MF, Cataletto ME Asthma. [Updated 2024 May 3]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2024 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK430901/ Gallardo A, Dévoli A, Gigliotti C, Zamarrón.-López E, Pérez Nieto OR, Núñez Silveira JM High Flow Nasal Cannula in Critically Ill Patients: a Narrative Review. Respirar [Internet]. 2023 Mar. 1 [cited 2024 Nov. 5];15(1):44–73 Additional Declarations The authors declare no competing interests. Cite Share Download PDF Status: Posted Version 1 posted 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. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. 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-6805022","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Case Report","associatedPublications":[],"authors":[{"id":465465513,"identity":"81d801c0-9434-4275-9461-1c2fb641dbce","order_by":0,"name":"Alexis Stephano Henales 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This condition necessitates hospitalization and is associated with high rates of intensive care unit (ICU) admissions. Mortality rates can reach 1\u0026ndash;4%, influenced by underlying comorbidities and the timeliness of intervention (\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e). Effective management typically includes bronchodilators, systemic corticosteroids, and, in severe instances, mechanical ventilation (\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e). Raising awareness and implementing early interventions are essential to reduce complications and improve patient outcomes (\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e).\u003c/p\u003e\n\u003ch3\u003eMechanism of Action of Sevoflurane in Status Asthmaticus\u003c/h3\u003e\n\u003cp\u003eSevoflurane plays a crucial role in the management of status asthmaticus due to its potent bronchodilatory properties. It reduces airway resistance by inhibiting voltage-gated calcium channels, which decreases intracellular calcium levels and relaxes bronchial smooth muscle (\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e). Additionally, sevoflurane interacts with GABAergic and glycinergic pathways, lowering airway reactivity and stabilizing respiratory function (\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e). Furthermore, it suppresses the release of inflammatory mediators, helping to alleviate airway hyperresponsiveness (\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e, \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e). By dampening vagal nerve-mediated bronchoconstriction, sevoflurane provides benefits for patients who do not respond to conventional therapies (\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eThis case report was based on the CARE guidelines for case reporting. Informed consent was obtained from the patient for the publication of the case.\u003c/p\u003e "},{"header":"CASE REPORT","content":"\u003cp\u003eA 66-year-old female with a 20-year history of asthma, managed occasionally with salbutamol spray, and type 2 diabetes mellitus for 5 years, managed with metformin, was admitted on 11/04/2024 for a scheduled extracapsular cataract extraction in the left eye. Medications administered included 400 mg of paracetamol, two doses of 25 mcg fentanyl, 4 mg of ondansetron, and local anesthesia with lidocaine for retrobulbar block, along with 50 ml of Hartmann's solution. The surgery lasted 35 minutes, and nasal cannulas were used throughout the procedure without any intraoperative incidents. The patient was transferred to the recovery room at 11:00 with the following vital signs: peripheral oxygen saturation (SpO₂) of 94% on nasal cannulas at 4 L/min, blood pressure (BP) of 121/88 mmHg, heart rate (HR) of 88 beats per minute, and no record of respiratory rate (RR).\u003c/p\u003e\u003cp\u003eAt 12:17 PM, the patient developed dyspnea and hypoxemia, with SpO₂ between 76% and 80%, HR of 103 bpm, BP of 161/93 mmHg, and audible wheezing. A face mask was applied to increase oxygen support; however, no improvement was observed, with SpO₂ dropping to 60%. Subsequently, 1 g of magnesium sulfate and 1 mg of epinephrine were administered. She was transferred to the operating room for 100% FiO₂ delivery using the anesthesia machine, during which she experienced cardiac arrest. Chest compressions were initiated, and orotracheal intubation was performed with a 6.5 F endotracheal tube. After a second cycle of compressions, spontaneous circulation returned. An arterial blood gas (ABG) test was performed at 12:50, revealing a partial arterial carbon dioxide pressure (PaCO₂) of 86 mmHg, pH of 7.03, partial arterial oxygen pressure (PaO₂) of 108 mmHg, lactate of 3.9 mmol/L, HCO₃ of 17.4, arterial oxygen saturation (SaO₂) of 95%, and a PaO₂/FiO₂ ratio of 108, indicating respiratory and metabolic acidosis.\u003c/p\u003e\u003cp\u003eHypoventilation and bilateral wheezing were noted, and three additional doses of 1 mg epinephrine were administered, along with two doses of 100 mg hydrocortisone, salbutamol sprays, and budesonide micronebulization. Oxygenation improved, with a new ABG test at 13:28 reporting PaCO₂ of 54 mmHg, pH of 7.21, lactate of 2.7 mmol/L, PaO₂ of 127 mmHg, SaO₂ of 98%, and a PaO₂/FiO₂ ratio of 254. The patient was extubated in the operating room but again developed hypoxemia and increased work of breathing (WOB). A laryngeal mask was placed for 30 minutes and later removed, after which an oxygen reservoir face mask was applied.\u003c/p\u003e\u003cp\u003eShe was admitted to the ICU with increased WOB, using sternocleidomastoid muscles and showing intense abdominal expiration, with wheezing in both hemithoraxes, stridor, a Glasgow Coma Scale (GCS) score of 14 points. High-intensity non-invasive ventilation (NIV) was initiated, with a pressure support (PS) aimed at achieving a tidal volume (Vt) of 10 ml/kg of predicted body weight, continuous positive airway pressure (CPAP) of 0 cmH₂O, flow trigger of 2 L/min, showing an obstructive flow pattern with peak expiratory flow (PEF) of 30 L/min. She was treated with salbutamol and ipratropium via vibrating mesh (Aerogen) and 50 mg IV ketamine, without improvement, leading to a loss of alertness and a silent chest and BP 96/59 mmHg. A decision was made for rapid sequence intubation, administering 100 mg/kg IV ketamine and 50 mg rocuronium, with intubation on the first attempt using a video laryngoscope and bougie, placing an 8 F tube without hypoxemia. An obstructive expiratory flow pattern was observed.\u003c/p\u003e\u003cp\u003eThe patient was placed on volume-controlled mode (AC-V) with an RR of 14 bpm, inspiratory flow of 40 L/min, Vt of 400 ml, PEEP of 0 cmH₂O, I:E ratio of 1:4, achieving complete exhalations, with measured autoPEEP of 0.8 cmH₂O, peak airway pressure (Paw) of 16 cmH₂O, resistive pressure of 6 cmH₂O, and plateau pressure (Pm) of 10 cmH₂O. Post-ventilatory management ABG test at 15:23 reported PaCO₂ of 54 mmHg, pH of 7.21, lactate of 2.7 mmol/L, PaO₂ of 127 mmHg, SaO₂ of 98%, and a PaO₂/FiO₂ ratio of 254. Continuous salbutamol and ipratropium nebulizations with vibrating mesh were administered for 2 hours, with wheezing persisting bilaterally; the RR was adjusted to 11 bpm, maintaining an I\u003c/p\u003e\u003cp\u003eratio of 1:4 for complete exhalations. Two hours later, Paw increased to 22 cmH₂O with a Pm increase to 12 cmH₂O and resistive pressure to 10 cmH₂O. Due to persistent bronchospasm and lack of improvement following conventional medical treatment, sevoflurane was administered via anaesthetic conserving device (ACD, Sedaconda), with an initial bolus of 1.5 ml, followed by a dose of 1.5 ml/h at 20:00 for 30 minutes. At 22:30, the dose was adjusted to 3 ml/h due to increased ventilatory effort and spontaneous RR of 24 bpm with a RASS of 3 points. At 23:30, the dose was raised to a maximum of 5 ml/h to maintain a mandatory RR of 11 bpm, Vt of 400 ml, I:E\u003c/p\u003e\u003cp\u003eof 1:4.4, FiO₂ of 28%, and SpO₂ of 92–96%.\u003c/p\u003e\u003cp\u003eThe next day, at 03:30, during a new episode of severe bronchospasm with a silent right hemithorax and barely audible wheezing in the left hemithorax, the sevoflurane dose was increased to 5.5 ml/h, resulting in rapid improvement. At 06:00, the sevoflurane dose was gradually decreased to 4 ml/h, then to 3 ml/h at 07:00. The patient presented with spontaneous respirations and a RASS of 0 points. A spontaneous breathing trial (SBT) with PEEP of 0 cmH₂O, PS of 0 cmH₂O, and FiO₂ of 28% was positive, with no dyspnea, leading to successful removal from mechanical ventilation. High-flow nasal cannulas (HFNC) were applied with a flow rate of 20 L/min, FiO₂ of 40%, aiming for SpO₂ of 94% and air temperature of 37°C to prevent bronchial reactions to cold air. The family member was allowed in the room for observation.\u003c/p\u003e\u003cp\u003ePost-extubation ABG revealed a PaCO₂ of 35 mmHg, pH of 7.44, PaO₂ of 88 mmHg, and lactate of 2.1 mmol/L. Salbutamol, ipratropium, and budesonide nebulizations with vibrating mesh were continued, and systemic corticosteroids were discontinued. The patient was discharged from the ICU the following day due to improvement, with treatment adjusted by the pulmonology department.\u003c/p\u003e"},{"header":"DISCUSSION","content":"\u003cp\u003eThis case illustrates the complexities involved in managing status asthmaticus, a critical condition that demands immediate medical attention and often requires intensive care support. In this instance, the asthmatic crisis was refractory to the standard treatment regimen, which included short-acting beta-agonists, anticholinergics via vibrating mesh nebulization, systemic corticosteroids, and even ketamine\u0026mdash;an option for patients unresponsive to conventional therapies (\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eThe use of sevoflurane in this scenario highlights its dual role as both an anesthetic and bronchodilator. Its mechanisms, including calcium channel inhibition and modulation of inflammatory responses, present a valuable therapeutic option when traditional treatments fail. A recent systematic review identified 18 case reports of sevoflurane used for status asthmaticus, revealing only one case of mortality among those receiving anesthesia during treatment (\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e). Despite the heterogeneity of these studies, sevoflurane emerges as a viable, safe, and likely effective option for patients who are refractory to conventional therapies.\u003c/p\u003e \u003cp\u003eAnother advantage of sevoflurane noted in this case was the rapid awakening associated with a reduction in the dose from 5 to 3 mL/h, facilitating an early weaning from mechanical ventilation. It is crucial to emphasize that the ventilatory management during invasive mechanical ventilation was aimed at preventing air trapping from the outset. A low respiratory rate and extended inspiratory-to-expiratory (I:E) ratios were employed to ensure complete exhalations, thereby avoiding dynamic hyperinflation (\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eAs the patient's ventilatory status improved, we conducted a spontaneous breathing trial with zero PEEP and pressure support, closely simulating the post-extubation mechanical state (\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e). In retrospect, we opted for high-flow nasal cannula (HFNC) support at 37\u0026deg;C following extubation, as we believe exposure to cold air and oxygen in the operating room may have triggered the asthmatic crisis. Therefore, we maintained relatively low FiO₂ and flow rates (\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eUltimately, this case underscores the need for vigilant monitoring and timely intervention to mitigate the risks associated with status asthmaticus. Early recognition and aggressive management are essential for improving outcomes in patients experiencing severe asthma exacerbations.\u003c/p\u003e\n\u003ch3\u003ePatient perspective\u003c/h3\u003e\n\u003cp\u003eThe patient was interviewed in the afternoon following her extubation. She reported experiencing amnesia from the time of cannulation until she began to awaken for the spontaneous ventilation trial. The only discomfort she mentioned was a mild sore throat and slight difficulty breathing. She exhibited no signs of delirium and, although she had been with her sister since extubation, expressed a desire to see the rest of her family. Overall, she appeared calm and free of anxiety.\u003c/p\u003e"},{"header":"CONCLUSION","content":"\u003cp\u003eThis case describes a severe asthma exacerbation triggered by a perioperative complication in a patient undergoing elective cataract surgery. Despite rapid progression to respiratory failure, hypoxemia, and bronchospasm unresponsive to conventional treatment, intensive measures\u0026mdash;including mechanical ventilation, bronchodilator therapy, and volatile anesthetic administration\u0026mdash;achieved gradual improvement. The patient\u0026rsquo;s condition stabilized with careful titration of sevoflurane and high-intensity non-invasive ventilation, allowing for successful extubation and discharge from the ICU. This case highlights the complexity of managing perioperative respiratory emergencies in patients with chronic asthma and the potential role of sevoflurane in refractory bronchospasm.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003eEthical Approval and Consent to participate: The consent and approval of the patient involved for publication for scientific purposes has been obtained in writing and signed; a copy of the consent is included in the appendices.\u003c/p\u003e\n\u003cp\u003eConsent for publication: We have the consent for publication from the patient and the head of the intensive care unit involved for the case report.\u003c/p\u003e\n\u003cp\u003eAvailability of supporting data: We have all the data to support the events previously described in the case report.\u003c/p\u003e\n\u003cp\u003eCompeting interests: Not applicable\u003c/p\u003e\n\u003cp\u003eFunding: Not applicable\u003c/p\u003e\n\u003cp\u003eAuthors' contributions\u003c/p\u003e\n\u003cp\u003eAcknowledgements\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eReddel HK, Bacharier LB, Bateman ED et al (2021) Global Initiative for Asthma Strategy 2021: GINA Update. 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Respirar [Internet]. 2023 Mar. 1 [cited 2024 Nov. 5];15(1):44\u0026ndash;73\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":true,"hideJournal":true,"highlight":"","institution":"Hospital General San Juan del Río","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Status asthmaticus, sevoflurane, mechanical ventilation, asthma exacerbation","lastPublishedDoi":"10.21203/rs.3.rs-6805022/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-6805022/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eThis case report describes a 66-year-old female patient with a 20-year history of asthma and type 2 diabetes mellitus, who was admitted for scheduled extracapsular cataract extraction. During recovery, she developed status asthmaticus, characterized by severe dyspnea, hypoxemia, and increased respiratory effort. Initial management included bronchodilators, systemic corticosteroids, and ketamine, but the patient remained unresponsive. The introduction of sevoflurane provided significant bronchodilatory effects, contributing to stabilization and early extubation. This case underscores the importance of timely interventions and the potential role of sevoflurane in managing refractory asthma exacerbations.\u003c/p\u003e","manuscriptTitle":"Management of Status Asthmaticus with Sevoflurane in the ICU: case report","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-06-04 12:46:45","doi":"10.21203/rs.3.rs-6805022/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"afd53d0c-3de2-48da-bc3e-f984326c4088","owner":[],"postedDate":"June 4th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[{"id":49414600,"name":"Anesthesiology \u0026 Pain Medicine"},{"id":49414601,"name":"Critical Care \u0026 Emergency Medicine"}],"tags":[],"updatedAt":"2025-06-04T12:46:45+00:00","versionOfRecord":[],"versionCreatedAt":"2025-06-04 12:46:45","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-6805022","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-6805022","identity":"rs-6805022","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}