Profile of respiratory evaluation through surface electromyography, manovacuometry, and espirometry in candidates on the liver transplant waiting list.

INTRODUCTION: Electromyography (EMG) is the examination of skeletal muscle membrane electrical activity in response to physiologic activation. In healthy muscles, the square root (root mean square [RMS] is related to the amplitude of the obtained signal. Respiratory muscles are studied, especially those important for compliance, the diaphragm and the rectus abdominis. An evaluation to detect respiratory muscle deficits among liver disease patients on the waiting list for transplantation may serve as an alternative to providing specific treatments reducing the possibility of respiratory complications after transplantation.

OBJECTIVE: To study muscle activity by evaluating respiratory and surface EMG of the right diaphragm and right rectus abdominis muscles in patients on the liver transplant waiting list.

METHOD: Respiratory evaluation of muscle strength (maximum inspiratory pressure [MIP] and maximum expiratory pressure [MEP]) with a manometer -300, +300 from Gen-air; spirometry with Easyware Spirometer version 2.20; pulse oximetry with Nonim oximeter; Model for End-Stage Liver Disease (MELD) score as well as surface EMG of the diaphragm and rectus abdominis muscles from EMG/Brazil were applied in healthy and liver diseased subjects.

RESULTS: The 87 liver disease patients showed a mean age of 53.9 ± 7.3 years, mean body mass index of 28.21 ± 5.04 kg/m2 with 24.14% smokers (n = 21) and 43.68% physically active (n = 38 p) showing Diaphragm RMS of 61.05 ± 68.48 μV; rectus abdominis RMS of 45.28 ± 53.82 μV; MEP of 100.28 ± 27.85 cm H(2)O; and MIP of 92.41 ± 29.77 cm H2O. The average MELD of studied patients was 16.5 ± 0.71.

CONCLUSION: The respiratory profiles of patients on the liver transplant waiting list concerning muscle support were precarious owing to ascites and motor adynamia.