Objective: This prospective cohort study aimed to evaluate whether end-tidal carbon dioxide (EtCO₂) levels measured during bag-valve-mask (BVM) ventilation can predict sustained return of spontaneous circulation (sustained ROSC) in patients with out-of-hospital cardiac arrest (OHCA).

Methods: From January 2018 to December 2020, OHCA patients treated by emergency medical services in Kishiwada City, Osaka Prefecture, were prospectively enrolled. Initial EtCO₂ levels measured during BVM ventilation were recorded in real-time.We performed logistic regression analysis to determine whether initial EtCO₂ was an independent predictor of sustained ROSC. To assess the added value of EtCO₂, we developed two prediction models: one including EtCO₂ and one excluding it. These models were compared using the area under the receiver operating characteristic curve (AUC). Model calibration and stability were evaluated via likelihood ratio testing and visual inspection of calibration plots.

Results: A total of 276 patients were included, of whom 72 achieved sustained ROSC. Logistic regression analysis showed that higher initial EtCO₂ levels were independently associated with sustained ROSC (odds ratio [OR] 1.55; 95% confidence interval [CI]: 1.05-2.28; p = 0.0276). While the model including EtCO₂ had a slightly higher AUC than the model excluding EtCO₂ (OR 0.77; 95% CI: 0.71-0.83 vs. OR 0.75; 95% CI: 0.69-0.81), the difference was not statistically significant (p = 0.0955). However, the likelihood ratio test indicated a significantly better model fit when EtCO₂ was included (p = 0.02), and the calibration plot showed improved alignment between predicted and observed outcomes in the EtCO₂-including model.

Conclusion: Initial EtCO₂ measured during BVM ventilation was an independent predictor of sustained ROSC in OHCA patients. Although the inclusion of EtCO₂ did not significantly improve model discrimination, it enhanced calibration, suggesting its potential to improve the reliability of clinical decision-making during resuscitation efforts.

This is a case report of lethal dose of potassium bichromate ingestion who survived after vomiting and intensive treatments. A male in their fifties without significant past medical history swallowed 20g of potassium bichromate as suicidal attempt. He was transferred to our hospital 12 hours after the intake. The gastrolavage removed orange-color sediments, suggesting the potassium bichromate from the history. Enteral activated charcoal and purgative medicine were administered in the emergency room. We also injected intramuscular dimercaprol and intravenous ascorbic acid for a week in the hospital unit. The patient underwent hemodialysis for three consecutive days. The patient developed transient liver damage, mild renal failure, intestinal dysmotility and aspiration pneumonia; however, recovered in 2 weeks and was referred to the near-by clinic for follow up with psychiatry consultation.

Cerebral vasospasm associated with aneurysmal subarachnoid hemorrhage (aSAH) is strongly linked to poor neurological outcomes, making its prevention critically important. Clazosentan, a selective endothelin A (ET_A) receptor antagonist, has shown promise in preventing cerebral vasospasm; however, fluid retention and other edema-related complications remain significant concerns. We report a case of a 74-year-old woman with aSAH who developed rapid-onset laryngeal edema immediately after extubation during clazosentan administration, requiring emergent reintubation. In this case, several contributing factors were considered, including relatively enhanced endothelin B (ET_B) receptor signaling due to ET_A blockade, systemic inflammation following SAH, and age-related endothelial fragility. These factors likely led to abnormal vascular hyperpermeability and localized mucosal edema. Anatomically, the larynx is predisposed to pronounced edema even with minimal vascular leakage, and mechanical stimulation during extubation may have triggered the acute airway obstruction. This case serves as a critical warning regarding the potential risk of upper airway edema during clazosentan therapy and highlights the necessity of thorough airway evaluation and heightened vigilance during extubation in patients receiving this medication.