Early Versus Late Advanced Airway Management for Pediatric Patients With Out-of-Hospital Cardiac Arrest.

STUDY OBJECTIVE: To determine the association between early versus late advanced airway management and improved outcomes in pediatric out-of-hospital cardiac arrest. METHODS: We performed a retrospective cohort study using data from the out-of-hospital cardiac arrest registry in Japan. We included pediatric patients (<18 years) with out-of-hospital cardiac arrest who had received advanced airway management (tracheal intubation, supraglottic airway, and esophageal obturator). The main exposure was early (≤20 minutes) versus late (>20 minutes) advanced airway management. The primary and secondary outcome measurements were survival and favorable neurologic outcomes at 1 month, respectively. To address resuscitation time bias, we performed risk-set matching analyses using time-dependent propensity scores. RESULTS: Out of the 864 pediatric patients with both out-of-hospital cardiac arrest and advanced airway management over 67 months (2014 to 2019), we included 667 patients with adequate data (77%). Of these 667 patients, advanced airway management was early for 354 (53%) and late for 313 (47%) patients. In the risk-set matching analysis, the risk of both survival (risk ratio 0.98 for early versus late [95% confidence interval 0.95 to 1.02]) and favorable 1-month neurologic outcomes (risk ratio 0.99 [95% confidence interval 0.97 to 1.00]) was similar between early and late advanced airway management groups. In sensitivity analyses, with time to early advanced airway management defined as ≤10 minutes and ≤30 minutes, both outcomes were again similar. CONCLUSION: In pediatric out-of-hospital cardiac arrest, the timing of advanced airway management may not affect patient outcomes, but randomized controlled trials are needed to address this question further.

Neck Point-of-Care Ultrasound for the Identification of Tongue-Base Cysts in Infants With Stridor: A Case Series.

ABSTRACT: Tongue-base cysts, which are occasionally categorized as vallecular cysts, are a rare yet potentially life-threatening cause of stridor in pediatric patients. Studies reporting the use of point-of-care ultrasound (POCUS) to identify tongue-base cysts are lacking. We present the case series of four infants in whom tongue-base cysts were detected using neck POCUS.

Advanced airway management for pediatric out-of-hospital cardiac arrest: A systematic review and network meta-analysis.

OBJECTIVES: Although airway management is important in pediatric resuscitation, the effectiveness of bag-mask ventilation (BMV) and advanced airway management (AAM), such as endotracheal intubation (ETI) and supraglottic airway (SGA) devices, for prehospital resuscitation of pediatric out-of-hospital cardiac arrest (OHCA) remains unclear. We aimed to determine the efficacy of AAM during prehospital resuscitation of pediatric OHCA cases. METHODS: We searched four databases from their inception to November 2022 and included randomized controlled trials and observational studies with appropriate adjustments for confounders that evaluated prehospital AAM for OHCA in children aged <18 years in quantitative synthesis. We compared three interventions (BMV, ETI, and SGA) via network meta-analysis using the GRADE Working Group approach. The outcome measures were survival and favorable neurological outcomes at hospital discharge or 1 month after cardiac arrest. RESULTS: Five studies (including one clinical trial and four cohort studies with rigorous confounding adjustment) involving 4852 patients were analyzed in our quantitative synthesis. Compared with ETI, BMV was associated with survival (relative risk [RR] 0.44 [95% confidence intervals (CI) 0.25-0.77]) (very low certainty). There were no significant association with survival in the other comparisons (SGA vs. BMV: RR 0.62 [95% CI 0.33-1.15] [low certainty], ETI vs. SGA: RR 0.71 [95% CI 0.39-1.32] [very low certainty]). There was no significant association with favorable neurological outcomes in any comparison (ETI vs. BMV: RR 0.33 [95% CI 0.11-1.02]; SGA vs. BMV: RR 0.50 [95% CI 0.14-1.80]; ETI vs. SGA: RR 0.66 [95% CI 0.18-2.46]) (all very low certainty). In the ranking analysis, the hierarches for efficacy for survival and favorable neurological outcome were BMV > SGA > ETI. CONCLUSION: Although the available evidence is from observational studies and its certainty is low to very low, prehospital AAM for pediatric OHCA did not improve outcomes.

Food protein-induced enterocolitis syndrome is an important differential diagnosis of vomiting in pediatric emergency.

BACKGROUND: The aim of this study was to clarify the clinical characteristics and management of infants with suspected acute food protein-induced enterocolitis syndrome (FPIES) who presented to the pediatric emergency department (ED) before and after the guidelines were published. METHODS: This was a retrospective cohort study. We classified the infants as "acute FPIES-like symptoms" who were younger than 12 months of age and visited the pediatric ED of the National Center for Child Health and Development due to vomiting 1-4 h after food ingestion without any causative disease, such as infection. The medical records of those infants in 2015 and 2021 were reviewed. We used the nonparametric Mann-Whitney U test to compare two groups for continuous variables, whereas chi-squared or Fisher's exact tests were used for nominal variables. RESULTS: The number of infants with acute FPIES-like symptoms was 15 (13%) in 2015 and 14 (15%) in 2021. The trigger foods were cow's milk or dairy products in half of the infants, and five as a result of ingestion of hen's eggs in 2021, compared to zero cases in 2015. Five in 2015 and 12 in 2021 required examination at the ED. Three in 2015 and six in 2021 met the diagnostic criteria for acute FPIES in the international consensus guidelines. The emergency physicians did not record at least four minor criteria for acute FPIES in seven in 2015 and five in 2021. No infants (0%) in 2015 and two (14%) in 2021 were referred to the allergy department by an emergency physician. CONCLUSIONS: Acute FPIES should be considered one of the differential diagnoses of vomiting, and pediatric medical staff should be aware of FPIES diagnostic criteria and appropriately refer suspected cases to a specialist.

Clinical Utility and Patient Distribution of Brief Resolved Unexplained Event Classification for Apparent Life-Threatening Events.

OBJECTIVES: In 2016, brief resolved unexplained events (BRUEs) were proposed as alternative concepts to apparent life-threatening event (ALTE). The clinical utility of managing ALTE cases according to the BRUE classification is controversial. To verify the clinical utility of the BRUE criteria, we evaluated the proportion of ALTE patients who met and those who did not meet the BRUE criteria and assessed the diagnoses and outcomes of each group. METHODS: We retrospectively investigated patients with ALTE younger than 12 months who visited the emergency department of the National Center for Child Health and Development from April 2008 to March 2020. The patients were classified into the higher-risk and lower-risk BRUE groups; however, those who did not meet the BRUE criteria were classified into the ALTE-not-BRUE group. We evaluated the diagnoses and outcomes of each group. Adverse outcomes included death, recurrence, aspiration, choking, trauma, infection, convulsions, heart disease, metabolic disease, allergies, and others. RESULTS: Over the period of 12 years, a total of 192 patients were included, among which 140 patients (71%) were classified into the ALTE-not-BRUE group, 43 (22%) into the higher-risk BRUE group, and 9 (5%) into the lower-risk BRUE group. Adverse outcomes occurred in 27 patients in the ALTE-not-BRUE group and 10 patients in the higher-risk BRUE group. No adverse outcome occurred in the lower-risk BRUE group. CONCLUSIONS: Many of the patients with ALTE were classified into the ALTE-not-BRUE group, suggesting that replacing ALTE with BRUE is difficult. Although patients classified as lower-risk BRUE showed no adverse outcomes, there were only a few of them. In the pediatric emergency medicine setting, the BRUE risk classification may be beneficial for certain patients.

Balance bike injuries: A retrospective chart review.

AIM: To determine the characteristics of balance bike injuries. METHODS: This study retrospectively identified patients injured while riding a balance bike and treated at one paediatric emergency department in urban Japan, from February 2015 to July 2020. Data extracted were patient age and sex, circumstances and location of the injury occurrence, helmet use, adult supervision, injury type and body site, treatment and emergency department disposition. Based on these data and the balance bike manual instructions, cases were classified as correct and incorrect balance bike use. RESULTS: The study assessed 78 patients, age 2-6 years (median 3 years; 73% male). Of these 78 patients, 63 did not follow balance bike manual instructions (80.8%); 34 (43.6%) were injured while riding in prohibited places of use; 45 (57.7%) were injured in prohibited situations of use; and 37 (47.4%) were injured despite adult supervision. A total of 124 injuries were noted; the most common injured body site was the face (49 injuries, 39.5%), followed by the head (40 injuries, 32.3%). Most injuries were contusions and abrasions (65 injuries, 52.4%). More serious injuries were intensive care unit admission with intracerebral haemorrhage (1 patient) and lateral condyle fracture with surgical repair (1 patient). CONCLUSIONS: Most of the 78 balance bike injuries (76 patients) were mild; 2 were more severe and required intensive care unit admission or operation. Parents must be aware of the rules and instructions for balance bike use and ensure that their children can use the balance bike correctly.

Benzodiazepine Use for Pediatric Patients With Suspected Nonconvulsive Status Epilepticus With or Without Simplified Electroencephalogram: A Retrospective Cohort Study.

OBJECTIVES: In the present study, we aimed to determine the changes in the administration rate of benzodiazepines for pediatric patients with suspected nonconvulsive status epilepticus (NCSE) before and after the introduction of simplified electroencephalography (sEEG) in the emergency department. METHODS: This retrospective cohort study included patients who were younger than 18 years and were admitted to the emergency department from August 1, 2009, to July 31, 2017, with altered level of consciousness and nonpurposeful movement of eyes or extremities after the cessation of convulsive status epilepticus. Patients with apparent persistent convulsions, those who were fully conscious on arrival, and those who were transferred from another hospital were excluded. The patients were categorized into pre and post groups based on the introduction of sEEG, and benzodiazepine administration was compared between the 2 groups. RESULTS: During the study period, 464 patients with status epilepticus visited our emergency department and 69 and 93 patients fulfilling the study criteria were categorized into the pre and post groups, respectively. There were no significant differences in patient background characteristics between the 2 groups. Simplified electroencephalography was recorded in 52 patients in the post group. Benzodiazepines were administered in 44 of 69 patients (63.8%) in the pre group and 44 of 93 (47.3%) in the post group, and the benzodiazepine administration rate was significantly decreased after the introduction of sEEG ( P = 0.04). The hospitalization rate was significantly lower in the post group, but there were no significant differences in the rates of intensive care unit admission, reconvulsion after discharge, and final diagnoses between the 2 groups. CONCLUSIONS: Simplified electroencephalography might aid in determining the need for anticonvulsant treatment for suspected NCSE in pediatric patients. Albeit not a definitive diagnostic tool, sEEG might be a reliable choice in the evaluation of pediatric patients with suspected NCSE.

Validation of the PECARN head trauma prediction rules in Japan: A multicenter prospective study.

BACKGROUND: Head trauma in children is one of the most common causes for emergency department visits. Although most trauma cases are minor, identifying those patients who have clinically important traumatic brain injury (ciTBI) is challenging. The Pediatric Emergency Care Applied Research Network (PECARN) head trauma prediction rules identifying children who do not require cranial computed tomography (CT) were validated and are used all over the world. However, these rules have not been validated with large cohort multicenter studies in Asia. OBJECTIVES: To investigate whether the PECARN rules can be safely applied to Japanese children. METHODS: We conducted a multicenter, prospective, observational cohort study. We included children younger than 16 with minor head trauma (Glasgow Coma Scale ≥14) who presented to the six participating centers within 24 h of their injuries between June 2016 and September 2017. The primary analysis was set to calculate the negative predictive value of the patients with very low risk by the PECARN rules, compared with a preset threshold of 99.85%. RESULTS: We included 6585 children of which 463 (7.0%) had head CT scans performed and 23 (0.35%) had ciTBI. There were two patients with ciTBI who were classified as very low risk. The negative predictive value, calculated as 99.96% (95%CI: 99.86-100.00; P = .019), was significantly superior compared with the preset threshold of 99.85%. CONCLUSIONS: The PECARN head trauma prediction rules seemed to be safely applicable to Japanese children. Further studies are needed to determine safety in hospitals where physicians do not have expertise in managing children.

Prognostic factors of acute neurological outcomes in infants with traumatic brain injury.

PURPOSE: The purpose of this study is to clarify risk factors for poor neurological outcomes and distinctive characteristics in infants with traumatic brain injury. METHODS: The study retrospectively reviewed data of 166 infants with traumatic intracranial hemorrhage from three tertiary institutions in Japan between 2002 and 2013. Univariate and multivariate analyses were used to identify clinical symptoms, vital signs, physical findings, and computed tomography findings associated with poor neurological outcomes at discharge from the intensive care unit. RESULTS: In univariate analysis, bradypnea, tachycardia, hypotension, dyscoria, retinal hemorrhage, subdural hematoma, cerebral edema, and a Glasgow Coma Scale (GCS) score of ≤ 12 were significantly associated with poor neurological outcomes (P < 0.05). In multivariate analysis, a GCS score of ≤ 12 (OR = 130.7; 95% CI, 7.3-2323.2; P < 0.001), cerebral edema (OR = 109.1; 95% CI, 7.2-1664.1; P < 0.001), retinal hemorrhage (OR = 7.2; 95% CI, 1.2-42.1; P = 0.027), and Pediatric Index of Mortality 2 score (OR = 1.6; 95% CI, 1.1-2.3; P = 0.018) were independently associated with poor neurological outcomes. Incidence of bradypnea in infants with a GCS score of ≤ 12 (25/42) was significantly higher than that in infants with GCS score of > 12 (27/90) (P = 0.001). CONCLUSIONS: Infants with a GCS score of ≤ 12 are likely to have respiratory disorders associated with traumatic brain injury. Physiological disorders may easily lead to secondary brain injury, resulting in poor neurological outcomes. Secondary brain injury should be prevented through early interventions based on vital signs and the GCS score.

Pulmonary Embolism Mimicking Infectious Pleuritis.

The diagnosis of pulmonary thromboembolism (PE) is often delayed because it is usually misdiagnosed as pneumonia or deep vein thrombosis. We report an unusual case of PE misdiagnosed as viral pleuritis on the first arrival at the emergency department (ED) in our hospital. A 14-year-old girl with no previous significant medical history was referred to the ED with pleuritic and chest pain with low-grade fever 4 days before admission. Echography showed a small amount of left pleural effusion. A 12-lead electrocardiogram was normal. She received a diagnosis of viral pleuritis. Two days before admission, she revisited ED with dyspnea and exacerbated pain. Echography showed slight increase in left pleural effusion. She had the same diagnosis. The chest pain remained at the same level. On the day of admission, she presented to ED with vomiting, watery diarrhea, abdominal pain, chest pain, and respiratory distress. Laboratory findings showed hypoalbuminemia and proteinuria. Echography showed a moderate amount of pleural effusion on both sides and no dilatation of the right cardiac ventricle. Contrast-enhanced chest computed tomography was performed to search the cause of the respiratory distress, which showed filling defects with contrast material in pulmonary arteries. A 12-lead electrocardiogram showed an S1Q3T3 pattern. She received a diagnosis of PE caused by nephrotic syndrome. Pulmonary thromboembolism can mimic infectious pleuritis and lead to misdiagnosis and/or delayed diagnosis. Thus, risk factors of PE should be considered in pediatric patients presenting with symptoms suggesting infectious pleuritis.

Effective Use of Computed Tomography for Detection of Press-Through-Package Sheet Ingestion in a Pediatric Patient.

Press-through-package sheet (PTPS) ingestion can cause perforation of gastrointestinal tract. Such incidents, which require immediate medical attention, are often observed in elderly people. In this report, we describe the case of a 12-year-old patient who ingested PTPS. The patient, who has attention-deficit/hyperactivity disorder, presented with abdominal pain at our hospital. While it was not revealed by a chest x-ray, computed tomography scan showed a PTPS lodged in his lower esophagus. The ingested PTPS was removed by endoscopy without complications. Press-through-package sheets ingestion can occur in pediatric patients, and computed tomography scan is useful in the diagnosis.

Oral analgesic for musculoskeletal injuries in children: A systematic review and network meta-analysis.

OBJECTIVE: Pain in pediatric musculoskeletal (MSK) injuries can lead to increased anxiety, fear, and avoidance of medical care, making analgesic management critical. Therefore, we evaluated analgesic efficacy and adverse effects to select the optimal analgesic agent in pediatric patients with MSK injuries. METHODS: Four databases were searched from inception to March 2023 for peer-reviewed, open randomized controlled trials (RCTs). Inclusion criteria were: (1) trials with RCT design, (2) children aged 1 month-18 years with MSK injury, (3) outpatient setting, (4) interventions and control, (5) primary outcome of pain score at 60 and 120 min and secondary outcome of adverse effects, and (6) full-text and peer-reviewed articles. Two reviewers screened, extracted data, and assessed the risk of bias. A frequentist random-effects network meta-analysis (NMA) was performed. Certainty of evidence was evaluated using the Grading of Recommendations, Assessment, Development, and Evaluation working group approach. RESULTS: We included eight trials comprising 1645 children. Ibuprofen was significantly associated with pain reduction at 120 min, compared with acetaminophen (SMD 0.31 [95% CI 0.11-0.51]; moderate certainty) and opioids (SMD 0.34 [95% CI 0.20-0.48]; moderate certainty). Compared with opioids alone, ibuprofen-opioid combination was significantly associated with pain reduction at 120 min (SMD 0.19 [95% CI 0.03-0.35]). No significant differences were found in pain interventions at 60 min. Ibuprofen had statistically fewer adverse events than opioids (RR, 0.54 [95% CI 0.33-0.90]; moderate certainty) and ibuprofen with opioids (RR 0.47 [95% CI 0.25-0.89]; moderate certainty). In terms of limitations, the eight RCTs included had relatively small sample sizes; only two were high-quality RCTs. CONCLUSIONS: Our NMA found ibuprofen to be the most effective and least adverse analgesic in pediatric patients with MSK injuries.

Retinal hemorrhages and damages from tractional forces associated with infantile abusive head trauma evaluated by wide-field fundus photography.

We evaluated the distribution and types of retinal hemorrhages (RHs) and other damages in eyes with abusive head trauma (AHT). This retrospective, consecutive case series of AHT and non-AHT conditions involved 54 children with AHT, 43 children with head bruises, and 49 children with blunt eye trauma, each of non-AHT supported by reliable witness accounts. RHs and other damage were evaluated using ophthalmoscopy and wide-field fundus photography. A variety of RH types and other damage were identified in the AHT group but not in the non-AHT group. RHs in AHT extended from the posterior pole to the far periphery in 77% of eyes and on/near the veins in 86% and arteries in 85%, most of which were in the far periphery. Retinoschisis, white-dot lesions, and retinal folds were seen even in the far periphery. RHs on/near the veins and arteries, retinoschisis, and retinal folds suggest a traumatic mechanism of the tractional force of the vitreous that is attached to the entire retinal surface. Identifying the distribution and arterio and venous origins of RHs is a key factor in determining the association with trauma. Thus, wide-field fundus photography is useful to record and evaluate the origin of the RHs and other retinal damage.

Early versus late advanced airway management for adult patients with out-of-hospital cardiac arrest: A time-dependent propensity score-matched analysis.

OBJECTIVE: The objective was to investigate whether early advanced airway management during the entire resuscitation period is associated with favorable neurological outcomes and survival in patients with out-of-hospital cardiac arrest (OHCA). METHODS: We performed a retrospective cohort study of patients with OHCA aged ≥18 years enrolled in OHCA registry in Japan who received advanced airway management during cardiac arrest between June 2014 and December 2020. To address resuscitation time bias, we performed risk set matching analyses in which patients who did and did not receive advanced airway management were matched at the same time point (min) using the time-dependent propensity score; further, we compared early (≤10 min) and late (>10 min) advanced airway management. The primary and secondary outcome measures were favorable neurological outcomes using Cerebral Performance Category scores and survival at 1 month after cardiac arrest. RESULTS: Of the 41,101 eligible patients, 21,446 patients received early advanced airway management. Thus, risk set matching was performed with a total of 42,866 patients. In the main analysis, early advanced airway management was significantly associated with favorable neurological outcomes (risk ratio [RR] 0.997, 95% confidence interval [CI] 0.995-0.999) and survival (RR 0.990, 95% CI 0.986-0.994) at 1 month after cardiac arrest. In the sensitivity analysis with early advanced airway management defined as ≤5 min and ≤20 min, the results were comparable. CONCLUSIONS: Although early advanced airway management was statistically significant for improved neurological outcomes and survival at 1 month after cardiac arrest, the RR was very close to 1, indicating that the timing of advanced airway management has minimal impact on clinical outcomes, and decisions should be made based on the individual needs of the patient.

Benefits to Clinicians of Nonpharmacological Distraction During Pediatric Medical Procedure.

CONTEXT: Nonpharmacologic distraction (NPD) during medical procedures in children is known to be beneficial to patients; however, no reviews have assessed their benefits to medical providers. OBJECTIVES: We aimed to assess the benefits of NPD to medical providers. DATA SOURCES: We searched 5 databases for relevant articles. STUDY SELECTION: Peer-reviewed published randomized controlled trials comparing NPD with standard care that included children who had undergone medical procedures were included. DATA EXTRACTION: Primary outcomes were procedure time, number of medical staff involved, and initial success rate of venipuncture. Two reviewers assessed the risk of bias by using the Cochrane Collaboration (Oxford, United Kingdom)'s Randomized Controlled Trials Risk of Bias Tool, and we performed a meta-analysis to assess efficacy. RESULTS: We included 22 trials with 1968 participants. The main NPD was audiovisual distraction, such as tablets. No significant difference was found in venipuncture procedure time (mean difference: -9.79; 95% confidence interval: -22.38 to 2.81; low certainty). We found no studies on the number of medical staff. CONCLUSIONS: Our review did not find any clear NPD-associated benefit for the medical provider. The review included a small amount of literature, analyzed a small number of cases, and had a low certainty of evidence regarding procedure duration; therefore, further studies are needed to conclude the benefits to clinicians of NPD.

Dissociation of inflammatory mediators and function: experimental lung injury in nonpulmonary sepsis.

BACKGROUND: Sepsis is a common indication for mechanical ventilation, which, with higher tidal volume, can cause ventilator-associated lung injury. Inflammatory mediators in the plasma or bronchoalveolar fluid are sometimes proposed as biomarkers in ICU patients. OBJECTIVE: To test the hypothesis that "priming" with subthreshold sepsis in a clinically relevant model would worsen lung function, increase ventilator-induced mediator production, and differentially impact systemic vs. pulmonary mediator levels. The model used was cecal ligation and perforation modified so that alone it caused lung inflammatory responses but not injury. METHODS AND MAIN RESULTS: Anesthetized mice were randomized to cecal ligation and perforation (vs. sham) with or without dexamethasone and 6 hrs later further randomized to: 1) sham, nonventilated, saline; 2) cecal ligation and perforation, nonventilated, saline; 3) cecal ligation and perforation, nonventilated, dexamethasone; 4) sham, high tidal volume, saline; 5) sham, high tidal volume, dexamethasone; 6) cecal ligation and perforation, high tidal volume, saline; or 7) cecal ligation and perforation, high tidal volume, dexamethasone. Mediators associated with sepsis and lung injury (cytokines: interleukin-6, tumor necrosis factor-α; chemokine: keratinocyte stimulating factor) were measured in the plasma and the bronchoalveolar lavage, and lung function (compliance, oxygenation, alveolar protein leak) assessed. High tidal volume and cecal ligation and perforation increased individual bronchoalveolar lavage and plasma mediators; high tidal volume but not cecal ligation and perforation impaired lung function. Priming of high tidal volume by cecal ligation and perforation intensified plasma and bronchoalveolar lavage mediators; the plasma (but not the bronchoalveolar lavage) mediators were inhibited by dexamethasone pretreatment. CONCLUSIONS: Mediator-but not functional-responses to high tidal volume are augmented by subthreshold sepsis priming. There is important discordance among systemic and pulmonary mediators, physiologic function, and response to corticosteroids; thus, mediator levels may be incomplete surrogates for measures of lung injury or response to therapy in the context of systemic sepsis.

Relationship between institutional ventilated COVID-19 case volume and in-hospital death: A multicenter cohort study.

BACKGROUND: The volume-outcome relationship in patients with severe Coronavirus disease 2019 (COVID-19) is unclear and is important for establishing a system for the medical care of severe COVID-19. This study aimed to evaluate the association between institutional case volume and outcomes in patients with ventilated COVID-19. METHODS: We analyzed patients with severe COVID-19 on ventilatory control aged > 17 years who were enrolled in the J-RECOVER study, which is a retrospective multicenter observational study conducted between January 2020 and September 2020 in Japan. Based on the ventilated COVID-19 case volume, the higher one-third of institutions were defined as high-volume centers, the middle one-third as middle-volume centers, and the lower one-third as low-volume centers. The primary outcome measure was in-hospital mortality during hospitalization due to COVID-19. Multivariate logistic regression analysis for in-hospital mortality and ventilated COVID-19 case volume was performed after adjusting for multiple propensity scores and in-hospital variables. To estimate the multiple propensity score, we fitted a multinomial logistic regression model, which fell into one of the three groups based on patient demographics and prehospital factors. RESULTS: We analyzed 561 patients who required ventilator management. In total, 159, 210, and 192 patients were admitted to low-volume (36 institutions, < 11 severe COVID-19 cases per institution during the study period), middle-volume (14 institutions, 11-25 severe cases per institution), and high-volume (5 institutions, > 25 severe cases per institution) centers, respectively. After adjustment for multiple propensity scores and in-hospital variables, admission to middle- and high-volume centers was not significantly associated with in-hospital death compared with admission to low-volume centers (adjusted odds ratio, 0.77 [95% confidence interval (CI): 0.46-1.29] and adjusted odds ratio, 0.76 [95% CI: 0.44-1.33], respectively). CONCLUSIONS: There may be no significant relationship between institutional case volume and in-hospital mortality in patients with ventilated COVID-19.