Effect of Prone Position in Severe Covid-19 Patients in a Referral Center: A Cohort Retrospective Study

Introduction: Covid-19 is defined as a pandemic disease by WHO, in November 2023, WHO recorded 772.1 million confirmed cases and 6.9 million deaths, including 68,382 confirmed cases and 1426 deaths in Madagascar. The management of severe cases of Covid-19 remains a challenge for the healthcare system in a resource-limited country, due to the consumption of human resources, the shortage of medical resources and the lack of capacity in resource-limited countries. Prone position (PP) improves survival in acute respiratory distress, and numerous studies have shown that during Covid-19, it reduces mortality rates at 28 and 90 days, and increases the number of days without mechanical ventilation. However, data on the beneficial effects of PP remain limited in low-income countries. In this context, our study aims to evaluate the benefits of the prone position for severe Covid-19 patients in a referral center in Madagascar. Method: This is a retrospective cohort study, during the 2nd and 3rd waves of COVID-19, over a period of 11 months in two wards managing COVID-19 cases. We included all patients aged 15 and over with severe forms of COVID-19 who required 6 l/min of oxygen therapy. Results: We enrolled 123 patients, including 40 in the prone position and 83 in the supine position, with a mean age of 60.5 ± 12 years. The prone position (DV) reduced the risk of probable complications of COVID-19 with a strong association in terms of use of respiratory assistance (OR = 0.15;95% CI = 0.05 - 0.47), respiratory deterioration (OR = 0.22;95% CI = 0.09 - 0.58), shock (OR = 0.30;95% CI = 0.11 - 0.79) and hemodynamic instability (OR = 0.33;95% CI = 0.12 - 0.95). Univariate analysis of the effect of prone position on SpO2 showed improvement with significant associations with SpO2 at Day 1- Day 3, D4 - D7, D8 - D14, and persisting even at D15 - D21, D3 and D2 before discharge, and at discharge. In the overall population, the mean length of hospital stay was 22.8 ± 22.1 days, with extremes of 1 and 67 days. Univariate analysis of the effect of the prone position showed a reduction in length of hospital stay with a strong association (p = 0.001) and a mean difference of 14 days. The prone position reduced mortality with a significant association (OR = 0.44;95% CI = 0.20 - 0.98). Conclusion: Awake prone position prevents complications of COVID, improves SPO2 even up to hospital discharge and reduces hospital stay. This practice is simple, less costly and suitable in low income countries.

Advances in the Use of Prone Cardiopulmonary Resuscitation During Spinal Surgery in the Prone Position

Spinal surgery is usually performed in the prone position, which is a longer and more difficult procedure and is prone to complications such as circulatory dysfunction and stress injuries. Among them, stress injury is the main complication of prone spine surgery, but the reasons for stress injury in prone spine surgery are not clear, and whether prone cardiopulmonary resuscitation (CPR) can be used needs to be further verified. Supine cardiopulmonary resuscitation is commonly used in posterior spinal surgery, retroperitoneal surgery, and so on, which can effectively improve the patient’s hypoxemia. Such surgeries require a high level of anesthetic management, and cardiopulmonary resuscitation is necessary if a patient in a prone position experiences cardiac arrest. In the process of cardiopulmonary resuscitation, supine cardiopulmonary resuscitation is often used, especially for some obese patients, if they are immediately changed to the supine position, it takes up more time, there may be wound infection, and there is a possibility of missing the optimal rescue and resuscitation time. Based on this, this paper reviews the use of prone-position cardiopulmonary resuscitation for spinal surgery in the prone position.

Effects of the prone position on arterial blood gas analysis and respiratory parameters of acute respiratory distress syndrome patients:An observational retrospective study

Objective:To investigate the effect of the first prone position on arterial blood gas analysis and respiratory parameters of acute respiratory distress syndrome(ARDS)patients with and without COVID.Methods:This study was conducted retrospectively with 22 COVID-ARDS and 22 non-COVID ARDS patients,who were placed in a prone position for at least 16 hours on the first day at the intensive care unit admission,and arterial blood gas analysis was taken in the pre-prone,prone and post-prone periods.Results:PaO2 were significantly increased in the pre-prone vs.prone comparison in both groups,but the increase in the PaO2/FiO2 ratio was not significant.In comparing the pre-prone vs.post-prone PaO2/FiO2 ratios,there was a significant difference only in the non-COVID ARDS group.Conclusions:The improved oxygenation provided by prone positioning is more permanent with the“post-prone effect”in non-COVID ARDS patients.This can be attributed to the differences in the pathogenesis of the two ARDS types.

Clinical evaluation of prone position ventilation in the treatment of acute respiratory distress syndrome induced by sepsis

BACKGROUND Acute respiratory distress syndrome(ARDS)is an acute,diffuse,inflammatory lung injury.Previous studies have shown prone position ventilation(PPV)to be associated with improvement in oxygenation.However,its role in patients with ARDS caused by sepsis remains unknown.AIM To analyze the clinical effects of PPV in patients with ARDS caused by sepsis.METHODS One hundred and two patients with ARDS were identified and divided into a control group(n=55)and a PPV treatment group(n=47).Outcomes included oxygenation index,lung compliance(Cst)and platform pressure(Pplat),which were compared between the two groups after ventilation.Other outcomes included heart rate(HR),mean arterial pressure(MAP),central venous pressure(CVP),left ventricular ejection fraction(LVEF),the length of mechanical ventilation time and intensive care unit(ICU)stay,and levels of C-reactive protein(CRP),procalcitonin(PCT),and interleukin-6(IL-6)after ventilation.Finally,mortality rate was also compared between the two groups.RESULTS On the first day after ventilation,the oxygenation index and Cst were higher and Pplat level was lower in the PPV group than in the conventional treatment group(P<0.05).There were no significant differences in oxygenation index,Cst,and Pplat levels between the two groups on the 2^(nd),4^(th),and 7^(th) day after ventilation(P>0.05).There were no significant differences in HR,MAP,CVP,LVEF,duration of mechanical ventilation and ICU stay,and the levels of CRP,PCT,and IL-6 between the two groups on the first day after ventilation(all P>0.05).The mortality rates on days 28 and 90 in the PPV and control groups were 12.77% and 29.09%,and 25.53% and 45.45%,respectively(P<0.05).CONCLUSION PPV may improve respiratory mechanics indices and may also have mortality benefit in patients with ARDS caused by sepsis.Finally,PPV was not shown to cause any adverse effects on hemodynamics and inflammation indices.

Short-term prone positioning for severe acute respiratory distress syndrome after cardiopulmonary bypass:A case report and literature review

BACKGROUND Aortic dissection is a complex and dangerous cardiovascular disease,with many complications in the perioperative period,including severe acute respiratory distress syndrome(ARDS),which affects prognosis and increases mortality.Despite the effect of prone positioning(PP)in improving oxygenation in patients with severe ARDS,reports about PP early after cardiac surgery are few and such an opt-ion may be an issue in cardiac surgery patients because of the recent sternotomy.CASE SUMMARY A 40-year-old male patient diagnosed with acute type A aortic dissection on October 22,2021 underwent ascending artery replacement plus total aortic arch replacement plus stent elephant trunk implantation under cardiopulmonary bypass.Unfortunately,he developed ARDS on postoperative day 1.Despite comprehensive treatment with aggressive pulmonary protective ventilation,fluid management with continuous renal replacement therapy,the condition continued to deteriorate and rapidly progressed to severe ARDS with a minimum oxygenation index of 51.We are ready to implement salvage therapy,including PP and extracorporeal membrane oxygenation(ECMO).Due to the large amount of pericardial mediastinal and thoracic drainage after thoracotomy,ECMO may result in massive postoperative bleeding.Prolonged prone ventilation is often inappropriate after thoracotomy.Therefore,we chose short-term PP for<6 h.Finally,the oxygenation index greatly improved and the diffuse exudation in both lungs of the patient was significantly reduced with short-term prone positioning.CONCLUSION Intermittent short-term PP can improve early postoperative severe ARDS after acute aortic dissection.

Sandwich Rolling over Method in Patients with Prone Position Ventilation

Background: Prone positioning is nowadays considered as one of the most effective strategies for patients with severe acute respiratory distress syndrome (ARDS). Prone position ventilation can lead to some severe complications. Effectively implement prone ventilation and reduce the incidence of complications become an important problem for clinical medical staff. Aims: To investigate whether the Sandwich rolling over method was convenient for clinical implementation and can reduce complications. Design: This is a single-center, retrospective, observational study. Results: The mean pronation cycles per patient were 6.11 ± 4.40. The mean time spent in prone position for each cycle was 10.05 ± 4.42 hours. Two patients developed a pressure sore and the positions were cheek, auricle and chest. The mean time it took from preparation to cover the patient with the quilt was 10.56 ± 4.35 minutes. Conclusions: This retrospective study has shown that under the close cooperation and supervision of the team, the implementation efficiency of prone position ventilation can be improved and the occurrence of complications can be reduced.

Prone position combined with high-flow nasal oxygen could benefit spontaneously breathing, severe COVID-19 patients:A case report

BACKGROUND Since the outbreak of coronavirus disease 2019(COVID-19)in Wuhan,China in December 2019,the overall fatality rate of severe and critical patients with COVID-19 is high and the effective therapy is limited.CASE SUMMARY In this case report,we describe a case of the successful combination of the prone position(PP)and high-flow nasal oxygen(HFNO)therapy in a spontaneously breathing,severe COVID-19 patient who presented with fever,fatigue and hypoxemia and was diagnosed by positive throat swab COVID-19 RNA testing.The therapy significantly improved the patient's clinical symptoms,oxygenation status,and radiological characteristics of lung injury during hospitalization,and the patient showed good tolerance and avoided intubation.Additionally,we did not find that medical staff wearing optimal airborne personal protective equipment(PPE)were infected by the new coronavirus in our institution.CONCLUSION We conclude that the combination of PP and HFNO could benefit spontaneously breathing,severe COVID-19 patients.The therapy does not increase risk of healthcare workers wearing optimal airborne PPE to become infected with virus particles.

Comparison of the dose to lung volume between supine and prone position during treatment planning

Objective The aim of the study was to compare the dose to lung volume in the supine and prone posi- tion while designing CyberKnife treatment plans to treat metastatic tumors in the spinous processes of the thoracic vertebrae, and offer a reference for reducing damage to normal tissues. Methods Nine cases of metastatic tumors in the spinous processes of the thoracic vertebrae were selected, and then we designed treatment plans based on the supine and prone positions and compared the results. Results In contrast with the treatment plan based on the prone position, the one for the supine position required 14862-36337 MU more; the lung D5% was 5.20-7.90 Gy higher; and the lung D20% was 2.61-5.73 Gy higher. The difference of dose to spine volume between the two plans was -2.21-2.67 Gy; to the skin volume was -3.93-7.85 Gy; and to the esophagus was 0.28-6.39 Gy. Conclusion The treatment plan based on the prone position of patients can better protect lung tissues than the one based on the supine position, and can also improve the avaUabilitv of beams.

Clinical Nursing for Patients Undergoing Prone-Position Laparoscopic Partial Nephrectomy

Objective:To explore effective nursing strategies for patients undergoing prone-position laparoscopic partial nephrectomy.Methods:A total of 19 patients undergoing prone-position laparoscopic partial nephrectomy were selected,with hospital admission spanning from January 2024 to June 2024.Patients were randomly divided into the study group(n=10)and the control group(n=9).The control group received basic nursing care,while the study group received comprehensive high-quality nursing care.The recovery period,length of hospital stay,complication rates,SCL-90 scores,and nursing quality scores were compared between the two groups.Results:The recovery period and hospital stay were significantly shorter in the study group compared to the control group(P<0.05).The complication rate in the study group was lower than that in the control group(P<0.05).After the nursing intervention,the SCL-90 scores of the study group were lower than those of the control group(P<0.05).Nursing quality scores were higher in the study group than in the control group(P<0.05).Conclusion:Comprehensive high-quality nursing intervention for patients undergoing prone-position laparoscopic partial nephrectomy can shorten the recovery period and hospital stay,reduce the complication rate,improve mental health,and enhance nursing quality,making it suitable for wider application in medical institutions.

Effect of Prone Position Ventilation in Patients with Severe Craniocerebral Injury Complicated with Pulmonary Infection

Objective:To investigate the effects of prone ventilation in patients with severe traumatic brain injury combined with pulmonary infection.Methods:A total of 100 patients with severe traumatic brain injury combined with pulmonary infection in the hospital were randomly divided into a prone ventilation group and a conventional ventilation group,with 50 patients in each group.The Glasgow Coma Scale(GCS)score,APACHE II score,sputum culture results,oxygenation indicators,and prognosis were compared between the two groups.Data were processed using SPSS 25.0 statistical software,and t-tests and chi-square tests were used to compare continuous and categorical variables,respectively.Results:The experimental group showed better oxygenation indicators,a lower positive rate of sputum cultures,and reduced intracranial pressure compared to the control group(all P<0.05).Multivariate Cox regression analysis indicated that GCS score,APACHE II score,and prone ventilation were independent risk factors affecting patient prognosis(all P<0.05).Conclusion:Prone ventilation can improve oxygenation,reduce the risk of pulmonary infection,and decrease intracranial pressure in patients with severe traumatic brain injury combined with pulmonary infection,thereby improving patient prognosis.GCS score and APACHE II score can serve as important indicators for prognostic evaluation.

Efficacy and safety of awake prone positioning in the treatment of non-intubated spontaneously breathing patients with COVID-19-related acute respiratory failure:A systematic review and meta-analysis

Background Since the beginning of the coronavirus disease 2019(COVID-19)pandemic,prone positioning has been widely applied for non-intubated,spontaneously breathing patients.However,the efficacy and safety of prone positioning in non-intubated patients with COVID-19-related acute hypoxemic respiratory failure remain unclear.We aimed to systematically analyze the outcomes associated with awake prone positioning(APP).Methods We conducted a systematic literature search of PubMed/MEDLINE,Cochrane Library,Embase,and Web of Science from January 1,2020,to June 3,2022.This study included adult patients with acute respiratory failure caused by COVID-19.The Preferred Reporting Items for Systematic Reviews and Meta-Analyses(PRISMA)guidelines were followed,and the study quality was assessed using the Cochrane risk-of-bias tool.The primary outcome was the reported cumulative intubation risk across randomized controlled trials(RCTs),and the effect estimates were calculated as risk ratios(RRs;95%confidence interval[CI]).Results A total of 495 studies were identified,of which 10 fulfilled the selection criteria,and 2294 patients were included.In comparison to supine positioning,APP significantly reduced the need for intubation in the overall population(RR=0.84,95%CI:0.74–0.95).The two groups showed no significant differences in the incidence of adverse events(RR=1.16,95%CI:0.48–2.76).The meta-analysis revealed no difference in mortality between the groups(RR=0.93,95%CI:0.77–1.11).Conclusions APP was safe and reduced the need for intubation in patients with respiratory failure associated with COVID-19.However,it did not significantly reduce mortality in comparison to usual care without prone positioning.

Prone positioning ventilation for treatment of acute lung injury and acute respiratory distress syndrome

Patients who are diagnosed with acute lung injury/acute respiratory distress syndrome （ALI/ARDS） usually have ventilation-perfusion mismatch, severe decrease in lung capacity, and gas exchange abnormalities. Health care workers have implemented various strategies in an attempt to compensate for these pathological alterations. By rotating patients with ALI/ARDS between the supine and prone position, it is possible to achieve a significant improvement in PaO2/FiO2, decrease shunting and therefore improve oxygenation without use of expensive, invasive and exprimental procedures. Prone positioning is a safe and effective way to improve ventilation when conventional strategies fail to initiate a patient response. Because a specific cure for ARDS is not available, the goat is to support the patients with therapies that cause the least amount of injury while the lungs have an opportunity to heat. Based on current data, a trial of prone positioning ventilation should be offeted to the patients who have ALI/ARDS in the early course of the disease. Published studies exhibit substantial heterogeneity in clinical results, suggesting that an adequately sized study optimizing the duration of pronmg ventilation strategy is warranted to enable definitive conclusions to be drawn.

Awake prone positioning for patients with COVID-19-induced acute hypoxemic respiratory failure

Whereas prone positioning of intubated patients suffering from acute respiratory distress syndrome represents the standard of care,proning non-intubated patients,so-called“awake prone positioning(APP),”has only recently gained popularity and undergone scientific evaluation.In this review,we summarize current evidence on physiological and clinical effects of APP on patients’centered outcomes,such as intubation and mortality,the safety of the technique,factors and predictors of success,practical issues for optimal implementation,and future areas of research.Current evidence supports using APP among patients suffering from acute hypoxemic respiratory failure due to COVID-19 and undergoing advanced respiratory support,such as high-flow nasal cannula,in an intensive care unit setting.Healthcare teams should aim to prone patients at least 8 h daily.Future research should focus on optimizing the tolerance of the technique and comprehensively evaluating benefits in other patient populations.

The effect of prone position for ventilatorassociated pneumonia in adult patients:a systematic review and meta-analysis

Background:The effect and safety of prone position(PP)in ventilator-associated pneumonia(VAP)patients was uncertain.We systematically reviewed the literature published to investigate whether PP benefits for patients with VAP compared with conventional supine position(SP).Methods:PubMed,EMbase,Cochrane Library,CNKI and WanFang Database were electronically searched to collect randomized controlled trials(RCTs)about the PP ventilation and SP ventilation in intensive care unit(ICU)patients from inception to May 2020.Meta-analysis was performed by Revan 5.3 software.Results:A total of 7 RCTs involving 1604 patients were included.Compared to regular SP ventilation,the PP ventilation group had no statistical significance in the four aspects.The results of subgroup analysis showed that the incidence of VAP and all-cause mortality were not affected by the patient’s initial oxygenation index.However,the incidence of VAP tended to decrease when the duration of PP ventilation was less than 16 hours per day.Meanwhile,the all-cause mortality was significantly decreased while the daily time was more than 16 hours.Conclusions:Current evidence showed that the PP ventilation could not decrease the incidence of VAP,all-cause mortality,length of mechanical ventilation,and ICU stay.However,the daily duration of PP ventilation may have an impact on the incidence of VAP and all-cause mortality in critical patients.

Arterial embolization for iatrogenic life.threatening bleeding from subcutaneous hypervascular tumor in prone position

Performing angiography in the prone position is a difficult technique; however it is useful in some emergency situation. We experienced a 60 years old male who was performed lipema excision on his back in his family doctor＇s clinic. Since massive arterial bleeding could not be controlled with manual astriction, he transferred to our hospital in prone position with hemodynamic instability. Operating field was not kept because of massive bleeding; therefore surgical treatment was impossible. We planed emergency arterial embolization （AE） in prone position. Hence we chose the left radial artery for vascular access. The left subclavicle arteriography showed many major and minor feeding arteries from left subclavicular and axillary arteries and a massive extravasation of the contrast medium. Three major feeding arteries were performed AE with gelatin sponge and steel coils, After AE, massive bleeding was controlled. He could discharge from our hospital on the 5th hospital day without any complication. Arterial embolization for lifethreatening bleeding from subcutaneous hypervascular tumor in the prone position is first report to our knowledge, and it is extremely rare. However we thought that this technique is useful for patients who could not turn in the supine position, e.g. massive bleeding during renal biopsy and penetrating trauma from back.

The efficacy and safety of one-stage endoscopy combined with intrarenal surgery(mini-nephrostomy tract)in the prone split-leg position for complex renal calculi

Background:The goal of this study was to determine the safety and efficacy of endoscopic combined intrarenal surgery(ECIRS)performed in the prone split-leg position for the treatment of complex renal stones.Materials and methods:A mature ECIRS protocol was designed.Retrospective analysis was conducted of medical records between January 2020 and December 2021 of patients with complex renal stones at one center who underwent ECIRS by 2 skilled surgeons using retrograde flexible ureteroscopy and mini-percutaneous nephrolithotomy in the prone split-leg position.Results:A total of 44 patients were included in this study.Mean stone size was 26.1±12.7 mm,and the number of calyces involved was 4.36±2.09.Mean operative time was 71.1±21.8 minutes.Postoperative decline in hemoglobin was 15.8±9.8 g/L.Seventy-five percent of patients achieved stone-free status.The mean number of residual stones was 2.8±2.3,and the mean residual stone size was 10.30±4.76 mm.Six patients(13.6%)developed postoperative complications,including 4 with fever during the first 2 days postoperatively and 2 patients with transient postoperative pain.No patients developed severe complications.Conclusions:Endoscopic combined intrarenal surgery in the prone split-leg position can be performed safely by experienced surgeons using retrograde flexible ureteroscopy in conjunction with mini-percutaneous nephrolithotomy as a successful technique for the treatment of complex renal stones.

Laparoscopic liver resection for posterosuperior tumors using caudal approach and postural changes: A new technical approach

Laparoscopic liver resection(LLR) for tumors in the posterosuperior liver [segment(S) 7 and deep S6] is a challenging clinical procedure. This area is located in the bottom of the small subphrenic space(rib cage), with the large and heavy right liver on it when the patient is in the supine position. Thus, LLR of this area is technically demanding because of the handling of the right liver which is necessary to obtain a fine surgical view, secure hemostasis and conduct the resection so as to achieve an appropriate surgical margin in the cage. Handling of the right liver may be performed by the hand-assisted approach, robotic liver resection or by using spacers, such as a sterile glove pouch. In addition, the operative field of posterosuperior resection is in the deep bottom area of the subphrenic cage, with the liver S6 obstructing the laparoscopic caudal view of lesions. The use of intercostal ports facilitates the direct lateral approach into the cage and to the target area, with the combination of mobilization of the liver. Postural changes during the LLR procedure have also been reported to facilitate the LLR for this area, such as left lateral positioning for posterior sectionectomy and semi-prone positioning for tumors in the posterosuperior segments. In our hospital, LLR procedures for posterosuperior tumors are performed via the caudal approach with postural changes. The left lateral position is used for posterior sectionectomy and the semi-prone position is used for S7 segmentectomy and partial resections of S7 and deep S6 without combined intercostal ports insertion. Although the movement of instruments is restricted in the caudal approach, compared to the lateral approach, port placement in the para-vertebra area makes the manipulation feasible and stable, with minimum damage to the environment around the liver.

Awake extracorporeal membrane oxygenation support for a critically ill COVID-19 patient:A case report

BACKGROUND A critically ill coronavirus disease 2019(COVID-19)patient complicated by acute respiratory distress syndrome is reported.The patient survived following treatment with awake veno-venous extracorporeal membrane oxygenation(ECMO).CASE SUMMARY A 53-year-old male patient attended our hospital following a cough for 11 d and fever for 9 d.According to his computed tomography(CT)scan and real-time reverse transcription–polymerase chain reaction assay of a throat swab,nucleic acid was positive,confirming that he had COVID-19.He was subsequently transferred to the intensive care unit due to respiratory failure.The patient received antiviral drugs,a small dose of glucocorticoid,and respiratory support,including mechanical ventilation,but the treatment effect was poor.On the 28th day after admission,veno-venous ECMO and prone position ventilation(PPV)were performed,combined with awake ECMO and other comprehensive rehabilitation measures.On the 17th day of ECMO,the patient started to improve and his chest CT and lung compliance improved.ECMO was discontinued after 27 days,and mechanical ventilation was also discontinued after 9 days.The patient was then transferred to the rehabilitation department.CONCLUSION COVID-19 can damage lung tissues and cause evident inflammatory exudation,thus affecting oxygenation function.Awake ECMO,PPV,and comprehensive rehabilitation are effective in patients with critical COVID-19 and respiratory failure.

Sudden unexpected death after acute symptomatic seizures in a patient on mechanical ventilation

Background:The mechanism of sudden unexpected death in epilepsy remains poorly understood.Seizure induced cardiac arrhythmia,central and obstructive apneas have been proposed as possible causes of death.Here we report a unique case of seizure related sudden unexpected death in a patient whose airway was fully protected by intubation and mechanic ventilation in the absence of fatal cardiac arrhythmia.Case presentation:A 70-year-old woman was undergoing mechanical ventilation and videoelectroencephalography(EEG)monitoring following two convulsive seizures with ictal hypoventilation and hypoxemia.Several hours after intubation,she suffered another generalized tonic clonic seizure lasted for 3 min and developed postictal generalized EEG suppression in the presence of stable vital signs with SpO2>90%.EEG suppression persisted throughout the postictal phase.There was a significant fluctuation of systolic blood pressure between 50 and 180 mmHg with several bouts of hypotension<60 mmHg.She remained unresponsive after the convulsive seizure and died of diffuse cerebral edema 12 h later.Autopsy revealed no clear cause of death,except for possible hypoxic and ischemic injury leading to the diffuse cerebral edema.Conclusion:Given the reliable periictal airway protection,neither seizure induced central apnea nor obstructive apnea appeared to be the direct cause of death in this unique case.In the absence of fatal cardiac arrhythmia,diffuse cerebral edema secondary to seizure-induced autonomic dysfunction,hypotension and hypoxemia might be the cause of death,highlighting the etiological heterogeneity of sudden unexpected death in epilepsy.