Recovery from severe cardio-respiratory failure: the trajectory of muscle mass, strength, function and health related quality of life

Background The impact of intensive care unit acquired weakness (ICUAW) is associated with reduced muscle mass, strength, function and health related quality of life (HRQoL). Patients suffering from severe cardio-respiratory failure are known to lose considerable muscle mass and strength in the first 7 days of admission to the intensive care unit (ICU). Furthermore, patients surviving critical illness have a considerable less HRQoL and physical function with long term outcomes such as inability to return to work being reported. However, more information regarding muscle loss and recovery is required when patients leave hospital. Currently there are no treatments for ICUAW as once the process is established management is supportive, such as physical therapy. Purpose We Sought to investigate the effects of severe cardio-respiratory failure, in patients receiving extra corporeal membrane oxygenation (ECMO), on ICUAW (including muscle mass, strength, function and HRQoL). Researching a real life model of ICUAW allows the observation of the loss of muscle mass and strength in the first stages of critical illness and severe cardio-respiratory failure. Methods Adults receiving ECMO for severe cardiorespiratory failure were included. Muscle mass was measured using ultrasound of the rectus femoris cross sectional area (RFcsa). Muscle strength was measured using hand held dynamometry for both hand held grip strength and isometric leg extension. HRQoL was measured using the EQ-5D-5L. Function was measured using the short physical performance battery (SPPB). Measurements were taken on day 0, day 7, ICU discharge, hospital discharge and at out-patient follow up. Results 17 patients were recruited with 10 patients completing follow up. Patients lost 24% muscle mass in the first 7 days of ICU admission and ECMO initiation, with muscle loss continuing up until ICU discharge. Contrary to the hypothesis only 50% of the patients were seen to recover muscle mass at follow up. Strength and function all considerably improved between ICU discharge and out patient follow up. The EQ5D crosswalk index supported this suggesting considerable functional improvement. Conclusion Patients in severe cardio-respiratory failure lose considerable muscle mass in the first 7 days of admission, with only 50% of these patients recovering the initial muscle loss at follow up. However, strength, function and HRQoL all improve following ICU discharge suggesting an element of functional recovery. Strength and function have shown to improve regardless of the status of the muscle mass. Therefore, given the advantages of the real-life model and novel findings, this could serve as a platform to assess muscle loss and recovery over a longer time frame continuing to build the understanding of the patients recovery trajectory from critical illness.Rectus Femoris Muscle MassHand-Held Grip Strength