Clinical characteristics of pneumothorax and pneumomediastinum in mechanical ventilated patients with coronavirus disease 2019: a case series.

BACKGROUND: Pneumothorax (PTX) and pneumomediastinum (PM) have been reported as potential complications in patients with coronavirus disease 2019 (COVID-19); however, their risk factors and etiology remain unknown. Herein, we investigated the clinical characteristics of mechanically ventilated patients with COVID-19 with PTX or PM. METHODS: We examined patients with severe COVID-19 requiring mechanical ventilation who were admitted to the intensive care unit of a tertiary-level emergency medical center in Tokyo, Japan between April 1, 2020. and October 31, 2021. We collected and analyzed the clinical characteristics of the patients who presented with either PTX or PM during mechanical ventilation. RESULTS: During the study period, a total of 165 patients required mechanical ventilation, and 15 patients with PTX/PM during mechanical ventilation were selected. Three patients with obvious causes were excluded, and the remaining 12 patients were analyzed (7.3%). The mortality rate in these patients was as high as 50%, demonstrating the difficulty of treatment in the presence of PTX/PM. PTX/PM occurred 14.5 days after intubation. A peak pressure of > 30 cmH2O was only apparent in one patient, suggesting that high positive pressure ventilation may be less involved than mentioned in the literature. In addition, the inspiratory effort was not strong in our group of patients. (P0.1 was 2.1 cm H2O [1.0-3.8]). CONCLUSION: Various factors are associated with the development of PTX/PM in patients on mechanical ventilation for COVID-19. We did not find a strong correlation between PTM/PM and barotrauma or strong inspiratory efforts, which have been identified as potential causes in previous studies.

Pre-hospital airway management and neurological status of patients with out-of-hospital cardiac arrest: A retrospective cohort study.

Purpose: Little is known about whether pre-hospital advanced airway management (AAM) under the presence of a physician could improve outcome of patients with cardiac arrest, compared with pre-hospital AAM under the absence of a physician. Methods: This retrospective multicentre-cohort study enrolled consecutive patients who were transported to participating hospitals after out-of-hospital cardiac arrest in Japan between 1 June 2014 and 31 December 2019. We included patients who underwent pre-hospital AAM and resuscitation after arrival at hospital, and who were ≥18 years of age, with medical aetiologies. The primary outcome was favourable neurological survival (Cerebral Performance Category score of 1 or 2) one month after cardiac arrest. The primary outcome was called one-month favourable neurological survival. The first confirmed cardiac rhythm was defined using 3-lead electrocardiogram monitor or an automated external defibrillator and by determining whether the carotid artery was pulsating. Previous research found that the presence of a pre-hospital physician was associated with improved patients' outcomes, after the type of first confirmed cardiac rhythm was considered. Therefore, the first confirmed cardiac rhythm in current study was subdivided into non-shockable or shockable groups. A multivariable logistic regression analysis was performed on propensity score-matched patients. Results: We analysed 16,703 patients. Among the 2,346 patients in the non-shockable group, 1.2% (N = 29) achieved the primary outcome. The adjusted odds ratio of pre-hospital AAM with or without a physician for the primary outcome in the results of the non-shockable group was 4.64 (95% confidence interval: 1.81-14.4). Among the 826 patients in the shockable group, 16.9% (N = 140) achieved the primary outcome and the adjusted odds ratio of pre-hospital AAM with or without a physician for the primary outcome in the results of the shockable group was 1.05 (95% confidence interval: 0.67-1.63). Conclusions: This retrospective multicentre-cohort study found that pre-hospital AAM under the presence of a physician was significantly associated with increased neurological outcome in specific patients with cardiac arrest, compared with pre-hospital AAM under the absence of a physician.

A successful case of extracorporeal membrane oxygenation treatment for intractable pneumothorax in a patient with COVID-19.

BACKGROUND: Some patients with coronavirus disease 2019 (COVID-19) develop pneumothorax. Tube thoracotomy and bulla resection could generate aerosols and cause virus transmission; the optimal treatment strategy remains unclear. CASE PRESENTATION: A 57-year-old male was transferred as a severe COVID-19 pneumonia case. On the 16th day after admission, the patient's respiratory condition deteriorated, and the chest X-ray revealed the presence of severe right-sided pneumothorax. A chest drain was immediately inserted; however, a significant air leak continued, and severe ventilator settings were required. Thus, veno-venous extracorporeal membrane oxygenation (VV-ECMO) treatment was initiated to allow the lungs to rest. After 10 days of lung-protective ventilation, the patient was weaned from ECMO and the chest drain was removed on the following day with no major comorbidities. CONCLUSION: The combination of ECMO with lung rest strategy could be a treatment option for intractable pneumothorax with COVID-19 to avoid unnecessary surgical procedures and aerosol generation.

COVID-19 pneumonia complicated by bilateral pneumothorax: A case report.

BACKGROUND: Pneumothorax is a rare but life-threatening complication associated with pneumonia caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). CASE PRESENTATION: Informed consent was obtained from the patient himself.A 50-year-old man presented with a 9-day history of fever, cough, and dyspnoea. He was diagnosed with coronavirus disease 2019 (COVID-19) pneumonia and was admitted to the Medical Hospital, Tokyo Medical and Dental University. Chest CT showed diffuse patchy ground-glass opacities (GGOs). His state of oxygenation deteriorated, and mechanical ventilation was initiated on day 4 after admission (12th day from onset). He improved gradually and was weaned from ventilation on day 15. Sudden onset of bilateral pneumothorax occurred on day 21 with severe respiratory failure, and chest CT revealed pneumatocele formation on both lower lobes. CONCLUSIONS: Pneumothorax is a notable complication in cases of severe COVID-19 pneumonia, especially in those who require positive-pressure ventilation.

Evaluation of manual chest compressions according to the updated cardiopulmonary resuscitation guidelines and the impact of feedback devices in an educational resuscitation course.

BACKGROUND: The cardiopulmonary resuscitation guidelines revised in 2015 recommend target chest compression rate (CCR) and chest compression depth (CCD) of 100-120 compressions per minute (cpm) and 5-6 cm, respectively. We hypothesized that the new guidelines are harder to comply with, even with proper feedback. METHODS: This prospective observational study using data collected from the participants of an Immediate Cardiac Life Support course included the evaluation of chest compressions using performance data from a feedback device after the completion of the course. Participants completed chest compressions for 1 min and were provided with feedback, after which they performed another cycle of CC. Primary outcome measures were CCR and CCD as well as the correct CCR percentage and CCD percentage for pre and post feedback. RESULTS: The study included a total of 88 participants. The median pre-CCR was 112.5 cpm (interquartile range [IQR] 108-116 cpm), and the median correct pre-CCR percentage was 96% (IQR 82.5-99.5%). After the feedback, there was a slight increase in the correct CCR percentage (99% [IQR 92.5-100%]). Conversely, the median pre-CCD was 5.4 cm (IQR 4.9-5.8 cm), and the median pre-correct CCD percentage was 66% (IQR 18.5-90%). The increase in the median post-correct CCD percentage to 72% (IQR 27-94%) observed after the feedback was not statistically significant (P = 0.361). CONCLUSIONS: Compliance with the new guidelines for chest compressions, especially those regarding the CCD, might be difficult. However, whether the changes in guidelines affect outcomes in actual clinical settings is uncertain and requires further investigation.

Decision-making criteria for damage control surgery in Japan.

Controversy still remains regarding the optimal criteria for selecting damage control surgery (DCS). Our objective was to propose an indication for implementing DCS for abdominal trauma requiring emergency laparotomy. This was a multicenter, retrospective, observational study that used data from the Japan Trauma Data Bank. Patients who underwent emergency laparotomy were included. We compared the patients regarding the performance of DCS. Of the 4447 patients included in the study, 532 patients were in the DCS group and 3915 patients were in the non-DCS group. Logistic regression analysis revealed that body temperature, level of consciousness (Glasgow Coma Scale), and type of injury (blunt or penetrating) were independent predictors of DCS. Using these predictors, we created the Damage Control Indication Detecting score. The score showed a positive correlation with mortality. The score was obtained as 5 of 9 points in total, revealing mortality of 30.8%, sensitivity of 64.8%, and specificity of 70.0%. The area under the curve for the receiver operating characteristic curve was 0.715. This score can help surgeons determine when to perform DCS. However, more than 95% of trauma cases in Japan involve blunt injuries, suggesting that the results of our study may not be applicable internationally.

Predictive ability and interobserver reliability of computed tomography findings for angioembolization in patients with pelvic fracture.

BACKGROUND: The purpose of this study was to identify computed tomography (CT) findings that predict the need for angioembolization in patients with pelvic fracture. METHODS: This retrospective cross-sectional study was performed between April 2006 and October 2015 at two urban emergency medical centers in Japan. The study included patients who underwent CT within 3 hours of arrival and were diagnosed with a pelvic fracture. The study outcome was undergoing angioembolization within 24 hours of arrival. Four independent readers blinded to all clinical information interpreted the CT scans for blush, thickness of retroperitoneal hematoma, and diameter and laterality of muscle swelling around the pelvis. Receiver operating characteristics analyses provided area under the receiver-operating characteristic curves (AUROC) and diagnostic indicators at the estimated thresholds including sensitivity, specificity, positive and negative predictive values and diagnostic odds ratio (DOR). The interobserver reliability of all radiographic findings was also evaluated. RESULTS: Fifty-two of 244 eligible patients underwent angioembolization. The predictive ability in terms of DOR was relatively better with blush on CT scan (sensitivity, 0.57; specificity, 0.86; DOR, 8.05) than with laterality of muscle swelling of 12.9 mm or greater (sensitivity, 0.79; specificity, 0.55; DOR, 4.60; AUROC, 0.75) and thickness of retroperitoneal hematoma of 22.7 mm or greater (sensitivity, 0.65; specificity, 0.74; DOR, 5.39; AUROC, 0.73). The interobserver reliability of blush, laterality of muscle swelling, and thickness of retroperitoneal hematoma was 0.43, 0.54, and 0.70, respectively. CONCLUSION: All of the tested CT findings failed to show both sufficient predictive ability and sufficient interobserver agreement. Further diagnostic accuracy studies to validate these findings or establish a prediction model incorporating these findings are expected. LEVEL OF EVIDENCE: Diagnostic, level V.