Anticipating mechanical ventilation in Guillain-Barre syndrome

Context: The combination of multiple clinical factors culminates in neuromuscular respiratory failure in up to 30% of the patients with Guillain-Barre syndrome (GBS). Although guidelines exist as to when to proceed with intubation, early indicators of subsequent progression to respiratory failure have not been established. Objectives: To identify clinical and respiratory features associated with progression to respiratory failure and to examine patterns of respiratory decline in patients with severe GBS. Design: Retrospective survey. Setting: Tertiary care hospital. Patients: One hundred fourteen consecutive patients with severe GBS admitted to the intensive care unit between January 1, 1976, and December 31, 1996. Main Outome Measures: Early markers of impending respiratory failure, requirement for mechanical ventilation, and patterns of respiratory decline. Methods: The clinical and electrophysiologic features of 60 patients receiving mechanical ventilation were compared with 54 patients with severe GBS who did not receive mechanical ventilation. Daily preventilation maximal inspiratory and maximal expiratory respiratory pressures and vital capacity were analyzed. Multivariate predictors of the necessity for mechanical ventilation were assessed using logistic regression analysis. Results: Progression to mechanical ventilation was highly likely to occur in those patients with rapid disease progression, bulbar dysfunction, bilateral facial weakness, or dysautonomia. Factors associated with progression to respiratory failure included vital capacity of less than 20 mL/kg, maximal inspiratory pressure less than 30 cm H2O, maximal expiratory pressure less than 40 cm H2O or a reduction of more than 30% in vital capacity, maximal inspiratory pressure, or maximal expiratory pressure. No clinical features predicted the pattern of respiratory decline; however, serial measurements of pulmonary function tests allowed detection of those at risk for respiratory failure. Conclusions: While inherently unpredictable, the course of patients with severe GBS can, to some extent, be predicted on the basis of clinical information and simple bedside tests of respiratory function. These data may be used in the decisions regarding admission to the intensive care unit and preparation for elective intubation.