AN OBSERVATIONAL STUDY ON THE EFFECTS OF IMPROVISED CPAP (ICPAP) IN CARDIOVASCULAR DISEASES WITH ACUTE RESPIRATORY FAILURE

Objectives: This study describes three surges of COVID-19 hypoxemic respiratory failure and our experience with using iCPAP in patients with cardiovascular diseases at a tertiary cardiac care centre. Methodology: This observational study was conducted from March 23^rd 2020 to May 31^st 2021, at The National Institute of Cardiovascular Diseases (NICVD), Karachi, Pakistan. This is an analysis of data from the PRICE Network Registry. Data was collected for all adult patients with cardiovascular diseases admitted with acute hypoxemic respiratory failure and a confirmed diagnosis of SARS CoV-2. Results: Among 362 patients with 'severe’ or 'critical’ COVID-19 were hospitalized; 163 (45%) in the 1^st surge, 92 (25.4%) in the 2^nd and 107 (29.6 %) in the 3^rd surge. All-cause mortality was 118 (32.6%). iCPAP was used in 39% (141) patients, 19% (69) patients required oxygen only, 25.4% (92) were on BiPAP support and 16.6% (60) were intubated. ‘iCPAP failure’ occurred in 48/141 (34%) patients. iCPAP failure occurred in patients with higher APACHE II scores (16.3 ±5.7 v/s 21.3±6, p ≤0.001), lower ROX index on admission (5.0±2.2 vs. 10.4±5.4, p≤0.001), lesser degree of improvement in ROX index at 48 hours (Day 3 ROX 18.7±8.9 vs. 9.9±6.3, p≤0.001). Mortality rate on iCPAP was 44 (31.2%). Conclusion: COVID-19 outcomes in a resource-limited setting in patients having cardiovascular diseases, appear comparable to global reports. A modification of standard CPAP (iCPAP) appeared to be safe and effective. This modification of standard CPAP (iCPAP) identifies an option for resource-limited or resource-exhausted critical care units.