Upper limb muscle strength and exercise endurance as predictors of successful extubation in mechanically ventilated patients

Abstract

BACKGROUND : Failed extubation increases the intensive care unit (ICU) length of stay, hospital length of stay, and financial costs and it reduces the patient’s functional ability. Avoiding failed extubation is of utmost importance, therefore predictors for successful extubation are paramount. OBJECTIVE : To determine if successful extubation in mechanically ventilated patients can be predicted by physiotherapists using upper limb muscle strength and exercise endurance. METHODS : Fifty-seven patients from the medical and trauma ICUs of a large academic hospital were eligible for testing. Muscle strength was evaluated using the Oxford grading scale, Medical Research Council score (MRC score), handgrip dynamometer, and maximum inspiratory pressure (MIP). Exercise endurance was tested while the patient was actively riding the MOTOmed ® letto2 cycle ergometer for six minutes with the upper limbs. RESULTS : Exercise endurance (time the patient rode actively) (P = 0.005), MRC-score (P = 0.007), and number of days ventilated (P = 0.005) were associated with successful extubation. The handgrip strength (P = 0.061), MIP (P = 0.095), and muscle strength of the sternocleidomastoid (P = 0.053) and trapezius muscles (P = 0.075) were marginally associated with successful extubation. Due to multicollinearity when developing the prediction equation, the final multivariable logistic regression prediction model included only exercise endurance and the number of days ventilated. The newly developed prediction equation conferred a sensitivity of 81.82% and a specificity of 77.14% to predict successful extubation. CONCLUSION : Successful extubation of mechanically ventilated patients can be predicted by physiotherapists using the newly developed prediction equation consisting of exercise endurance and number of days ventilated.