Propranolol on Post Stroke Immune Status and Infection

Stroke-associated pneumonia (SAP) is one of the important risk factors influencing poor outcomes and death in stroke patients. Over the past two decades, accumulating evidence suggests that post-stroke brain injury mobilizes the adrenergic system, which induces post-stroke immunosuppression and SAP. This study is designed to test the safety and efficacy of an adrenergic β-receptor blocker, propranolol, with or without combination of antibiotics, in reducing SAP in stroke patients. The underlying immune mechanisms will be investigated.

Stroke patients meeting the inclusion criteria will be randomly assigned at a 1:1:1 ratio into groups of standard treatment (blank-controlled), propranolol, or propranolol + ceftriaxone. Patients will be given 10.0mg\*3/day oral/nil propranolol alone or combined with 2.0g/day intravenous ceftriaxone over the course of 7 consecutive days. Neurological functions of these patients will be assessed at the baseline, day 7, 14, 30, and 90 after randomization. Head magnetic resonance imaging (MRI) will be performed at baseline and 7 days after randomization. Chest computed tomography (CT) will be performed within 7 days following randomization. Abdomen CT will be performed simultaneously with CT chest to evaluate spleen volume. For patients requiring acute endotracheal intubation upon admission, bronchoalveolar lavage fluid will be harvested at baseline and 7 days post-randomization. For all patients, 15 mL intravenous blood will be collected at baseline, days 3 and 7 after randomization. Bronchoalveolar lavage fluid and blood will be used to explore the peripheral and pulmonary immune status of patients. Urinary tract infection will be evaluated within 14 days based on routine urine test and bacterial culture.