Neuromuscular dysfunction associated with delayed weaning from mechanical ventilation in patients with respiratory failure

Background: Mechanical ventilation offers essential ventilatory support, while the respiratory system recovers from acute respiratory failure. Yet, invasive mechanical ventilation is associated with risks and complications that prolong the duration of mechanical ventilation and increase the risk of death. Neuromuscular dysfunctions acquired during intensive care unit (ICU) stay are considered to be one of the important factors that impair the weaning process. The aim of this work: To evaluate the role of the neuromuscular factors responsible for difficult weaning from mechanical ventilation. Methods: The study included 19 patients with difficult weaning from mechanical ventilation from the Alexandria medical respiratory intensive care unit (ICU) during the period from May 2009 till May 2010. The selected patients included patients who need mechanical ventilation for medical reasons, Patient fulfilling the parameters for weaning, (59) with failed spontaneous breathing trial. In the present study EMG and sensory-motor nerve conduction study was done. Results: 26% show normal study, 63% showed moderate to severe axonal sensory-motor peripheral neuropathy and 11% showed a picture of myopathy. The study revealed that 33% of the patients with peripheral neuropathy failed weaning trials and finally died. It is also found that drugs taken during ICU stay as corticosteroids and electrolyte disturbances (hypocalcaemia, hypophosphatemia, and hypomagnesaemia) may be related to the occurrence of neuromuscular dysfunctions. The present work also revealed a significant relationship between hypoalbuminemia and neuromuscular dysfunction. Conclusions: The present study stresses on the importance of neuromuscular assessment in all cases with difficult weaning as this may be an important contributing factor for difficult weaning and prolonged mechanical ventilation (neuropathic or myopathic in origin). EMG and nerve conduction study may be of help for the detection of such disturbances. So, proper assessment of the neuromuscular apparatus and the management of any disorder may be a great step toward successful weaning. (C) 2012 Alexandria University Faculty of Medicine. Production and hosting by Elsevier B.V. All rights reserved.