Mechanical ventilation in patients with hemispheric ischemic stroke

Abstract

Objective Whether stroke patients should be ventilated mechanically is still a contentious issue, because their outcome is very poor. We wanted to investigate how often mechanical ventilation is indicated in patients with hemispheric ischemic stroke as well as the outcome of these patients and the factors by which outcome is influenced. Design Prospective case series. Setting University hospital, neurocritical care unit. Subjects Subjects were 218 patients who met the following inclusion criteria: age 18–85 yrs, acute hemispheric ischemic infarction, clinical examination, and computed tomography within 6 hrs after the onset of symptoms. Interventions Mechanical ventilation was instituted with one or more of the following conditions: deterioration of consciousness with the inability to protect the airway; Pao₂ of 60 mm Hg; breath rate of >40 breaths/min; and left heart insufficiency with definitive or impending pulmonary edema. Measurements and Main Results Mechanical ventilation was indicated for 52 (24%) of the 218 patients: in 47 (90%) patients because of deterioration of consciousness, and in five (10%) patients because of heart insufficiency and/or pneumonia. In a logistic regression model, the history of hypertension and a size of infarction exceeding two thirds of the middle cerebral artery territory were independent variables for the application of mechanical ventilation. After 3 months, 42 (81%) of these 52 patients had died. The most common cause of death was fatal midbrain herniation caused by complete middle cerebral artery infarction. Patients who survived had a good-to-fair outcome. Conclusions New therapeutic strategies (e.g., hemicraniectomy) must be developed to reduce mortality and improve the outcome for this subgroup of ischemic stroke patients. Mechanical ventilation is and will remain a crucial element within such new concepts.