Intensive care unit acquired weakness, handgrip strength, and mortality in critically ill patients

A Prospective Evaluation of Grip Strength Comparing a Low-Tech Method to Dynanometry in Preoperative Surgical Patients and Weak Intensive Care Patients

Objective. Grip strength testing offers a mechanism to identify patients in whom frailty might be present, discriminate between robust elderly and vulnerable younger patients, and can be used as a tool to track changes in muscle bulk over the course of an inpatient stay. We compared gold-standard quantitative grip strength measurement to a low-tech alternative, a manual bedside sphygmomanometer. Design. Under supervision, subjects performed hand-grip strength testing with each instrument. A mean score is calculated from three measurements on the dominant and nondominant hand. Setting. Testing was performed in a tertiary centre in Perth, Western Australia, in both outpatient clinics and intensive care units. Participants. 51 adult pre-operative surgical outpatients were assessed, alongside 20 intensive care inpatients identified as being weak. Main outcome measures. A statistical correlation between the two measures was evaluated. Feasibility, safety, and convenience were also assessed in outpatient and bedside settings. Results. Highly correlated results in both tertiary surgical outpatients (rs = 0.895, $p\le 0.001$ , N = 102; r (100) = 0.899, $p\le 0.001$ ) and weak intensive care patients (rs = 0.933, $p\le 0.001$ , N = 39 r (37) = 0.935, $p\le 0.001$ ) Conclusions. Modifying a manual bedside sphygmomanometer to measure grip strength is feasible and correlates well with a formal dynamometer in preadmission surgical patients and weak patients in the intensive care unit. The use of an existing, safe, and available device removes barriers to the measurement of weakness in patients and may encourage uptake of objective measurement in multiple settings.

Muscle weakness assessment in older intensive care unit patients

INTRODUCTION: After long periods of hospitalization, older adults may develop muscle weakness that can affect their functional independence after discharge. OBJECTIVE: To assess muscle weakness in older patients admitted to an ICU. METHOD: This cross-sectional, descriptive study with a quantitative approach assessed functional independence with the Katz Index and post-ICU muscle strength with a handgrip strength (HS) test and the Medical Research Council (MRC) sum-score. The sample consisted of 60 patients with an average age of 76 (60–99) years, 36 (60%) of whom were female. RESULTS: Post-ICU, 86.7% of the patients were functionally dependent. Female patients had significantly lower HS than males: 7 (0–24) vs. 17 (1–37) (p < 0.001). Female patients who received mechanical ventilation (MV) or sedation had significantly lower HS and MRC scores than those who did not (p < 0.001): HS MV 1 (0–13) vs. 11 (0–24) p < 0.001; MRC MV 35 (14–48) vs. 43 (27–57) p < 0.001; HS sedation 0 (0–12) vs. 9 (0–24) p < 0.001; MRC sedation 34 (14–36) vs. 42 (22–57) p < 0.001, respectively. Finally, there was an inversely proportional correlation between HS, MRC scores, and ICU length of stay, Spearman’s rho = -0.267 (p = 0.0039) and Spearman’s rho = -0.347 (p = 0.007), respectively. CONCLUSION: Older women who received mechanical ventilation and sedation have lower muscle strength than those who did not. As the ICU length of stay increases, muscle strength decreases.