Exploring Peripheral and Respiratory Muscle Weakness and Functional Impairments in ICU Patients: Insights From a Resource-Constrained Setting.

Abstract

Importance and objectives: The aim of this study was to explore peripheral and respiratory muscle structure and strength from unit admission to hospital discharge among ICU patients in a resource-constrained setting.

Design: Prospective, observational study.

Setting: Tertiary academic hospital.

Participants: Newly intubated critically ill adults admitted to the medical and surgical ICUs and expected to be mechanically ventilated for more than 48 hours were included in the study.

Main outcomes and measures: Ultrasonography of the right hemi-diaphragm and quadriceps muscles were taken at admission for 3 consecutive days. Respiratory and peripheral muscle strength were evaluated using the Medical Research Council-Sum Score, dynamometry and maximal inspiratory pressure (MIP) at awakening, ICU discharge and hospital discharge.

Results: Forty-five participants were included, with a median (interquartile range) age of 34.5 (24.3-47.4) years and 73% were male. Most of the change in diaphragm thickness was observed on day 3, with 5 (22%) participants showing a decrease of more than 10% from baseline. Minimal changes in rectus femoris cross-sectional area were noted during the first 3 days. Eleven participants (44%) presented with ICU-acquired weakness at awakening, which decreased to 7 (29%) participants at ICU discharge and 5 (24%) participants at hospital discharge. The mean ± sd percentage of predicted quadriceps force was 22.2 ± 5.1 N at hospital discharge. The mean ± sd percentage of predicted MIP scores was 29.6% ± 10.5% at ICU discharge and 29.1% ± 8.6% at hospital discharge.

Conclusions and relevance: Patients discharged from the ICU in a resource-constrained setting presented with peripheral and respiratory muscle weakness, with minimal change in muscle structure shown by ultrasonography, despite short ICU stays, low Acute Physiology and Chronic Health Evaluation II scores, and a relatively young age. Future research should explore whether these findings indicate a distinct phenotype of critical illness in such environments.