ABSTRACT
SESSION TITLE: Lessons Learned from Critical Care Cases SESSION TYPE: Rapid Fire Case Reports PRESENTED ON: 10/18/2022 12:25 pm - 01:25 pm INTRODUCTION: Local compression of the anterior chest wall (CACC) or abdomen has been shown to unexpectedly improve respiratory system compliance in patients with severe acute respiratory distress syndrome (ARDS). The mechanism is thought to be similar to prone positioning, causing a redistribution of transpulmonary pressures. Limited data exists regarding this topic, particularly as it applies to COVID-19. We describe two cases of improved compliance and oxygenation with CACC in individuals with COVID-19 related ARDS, including one with prior lung transplantation. CASE PRESENTATION: Case 1: The patient was an unvaccinated 79 year-old man diagnosed with COVID-19 on admission. One week later, he progressed to requiring CPAP therapy. He was intubated the following week. Prone ventilation was initially attempted, but this was discontinued due to hemodynamic instability. Despite neuromuscular blockade and lung-protective ventilation, the patient's respiratory mechanics continued to worsen. CACC was then initiated using a 10 lb sandbag on the upper thorax, resulting in improved compliance (8 to 11.4 mL/cmH2O) and driving pressure (30 to 21 cmH2O). While CACC allowed room to adjust PEEP, there was no significant change in oxygenation or paCO2. Case 2: The patient was a fully vaccinated 46 year-old man with a history of bilateral lung transplant for cystic fibrosis, who tested positive for COVID-19 and was treated with sotrovimab as an outpatient. Despite early treatment, the patient had worsening hypoxia necessitating admission, treatment with bilevel PAP therapy, and subsequent intubation. Prone ventilation was initiated, but discontinued after 1 day due to worsening hemodynamics and poor improvement. CACC was then employed using two 5 lb sandbags with an improvement in compliance (16.7 to 21.1 mL/cmH2O). There was also a significant improvement in oxygenation (P/F ratio 115 from 86) and a decrease in paCO2. Following this favorable response, prone positioning was resumed, demonstrating similar improvement in respiratory mechanics. DISCUSSION: These cases demonstrate improved respiratory mechanics with CACC, which may be due to a reduction in end-inspiratory over-distention. In the first case, CACC allowed for an increase in PEEP when prone ventilation was not tolerated. In the second case, it was a tool that directed clinicians to resume prone positioning, with favorable improvement in oxygenation. The decrease in paCO2 may signify improved V/Q matching and dead space ventilation. CONCLUSIONS: This case series illustrates CACC as a potential therapeutic and diagnostic tool for clinicians to make lung-protective ventilator adjustments in responders. Trials of CACC may improve compliance and oxygenation in these patients, and may indicate those who would benefit from further prone positioning. Additional investigation is needed to clarify the clinical role of CACC for the management of COVID-19 related ARDS. Reference #1: Marini JJ, Gattinoni L. Improving lung compliance by external compression of the chest wall. Crit Care. 2021;25(1):264. Published 2021 Jul 28. doi:10.1186/s13054-021-03700-8 DISCLOSURES: Speaker/Speaker's Bureau relationship with boehringer ingelheim Please note: $5001 - $20000 by Brad Bemiss, value=Travel and payment for lecture No relevant relationships by Anila Khan No relevant relationships by Rishi Mehta No relevant relationships by Jason Peng