Effects of Intraoperative Lung-Protective Ventilation on Clinical Outcomes in Patients With Traumatic Brain Injury: A Randomized Controlled Trial

Background: Secondary lung injury is the most common non-neurological complication after traumatic brain injury (TBI). Lung-protective ventilation (LPV) has been proven to improve perioperative oxygenation and lung compliance in some critical patients. This study aimed to investigate whether intraoperative LPV could improve respiratory function and prevent postoperative complications in emergency TBI patients. Methods: Ninety TBI patients were randomly allocated to three groups (1:1:1): Group A, conventional mechanical ventilation [tidal volume (VT) 10mL/kg only]; Group B, small VT (8mL/kg) + positive end-expiratory pressure (PEEP) (5cmH 2 O); Group C, small VT (8mL/kg) + PEEP (5cmH 2 O) + recruitment maneuvers (RMs). Primary outcomes were intraoperative respiratory mechanics parameters and incidences of postoperative pulmonary complications; Secondary outcomes were serum levels of brain injury markers and incidences of postoperative neurological complications. Results: Seventy-nine patients completed final analysis. Intraoperative PaO 2 and dynamic pulmonary compliance of Group B and C were higher than those of Group A ( P =0.028; P =0.005), while their airway peak pressure and plateau pressure were lower than those of group A ( P =0.004; P =0.005). Compared to Group A, postoperative 30-day incidences of hypoxemia, pulmonary infection and atelectasis of the other two groups significantly decreased (52.0% vs . 14.3% vs . 19.2%, P =0.005; 84.0% vs . 50.0% vs . 42.3%, P =0.006; 24.0% vs . 3.6% vs . 0.0%, P =0.004). Moreover, intraoperative hypotension in Group C was more frequent than that in Group A and B ( P =0.007). At the end of surgery, serum levels of glial fibrillary acidic protein and ubiquitin carboxyl-terminal hydrolase isozyme L1 in Group B were lower than those in group A and C ( P =0.002; P <0.001). Postoperative incidences of neurological complications among three groups were comparable. Conclusions: Intraoperative continuous administration of small VT + PEEP is beneficial to TBI patients. Additional RMs with caution can be performed to prevent the disturbance of the stability of cerebral hemodynamics. Trial registration: Chinese Clinical Trial Registry (ChiCTR2000038314), retrospectively registered on September 17, 2020.