Is plasma calcium concentration implicated in the development of critical illness polyneuropathy and myopathy?

INTRODUCTION This prospective study investigated whether plasma ionized calcium concentration abnormalities and other electrolyte disturbances represent risk factors for the development of critical illness polyneuromyopathy (CIPNM) in ICU patients. METHODS One hundred and ninety consecutive adult critically ill patients with prolonged ICU stay (longer than 7 days) were prospectively evaluated. Patients with acute weakness and/or weaning difficulties were subjected to extensive electrophysiological measurements in order to establish the diagnosis of CIPNM. All recognized and/or possible risk factors for development of CIPNM were recorded. RESULTS The diagnosis of CIPNM was confirmed in 40 patients (21.05%). By applying a logistic regression model, hypocalcemia (P = 0.02), hypercalcemia (P = 0.01) and septic shock (P = 0.04) were independently associated with the development of CIPNM in critically ill patients. CONCLUSIONS We found that septic shock and abnormal fluctuations of plasma Ca²⁺ concentration represent significant risk factors for the development of CIPNM in critically ill patients.