Incidence and distribution of various arterial territories involved in postoperative neurological complications in patients undergoing cardiovascular surgery: A single centre retrospective analysis

Background: Neurological complications (NCs) (stroke) remain a devastating complication after cardiovascular surgical procedures despite advances in perioperative monitoring and management. The incidence of NC related to cardiovascular surgeries (CS) is comparatively very high and associated with high morbidity and mortality. The aim of this study is to evaluate the overall incidence of neurological complications in adult as well as pediatric patients and various pattern of neurological injury on noncontrast computed tomography head (NCCT) associated with various types of CS. Materials and Methods: We retrospectively analyzed all the NCCT heads of the postoperative cardiovascular surgery patients done in the immediate and early postoperative period (<7 days) who developed postoperative neurological deficits between April 2016 and February 2020. The medical records of all these cardiac surgery patients were analyzed for various variants such as the total number of patients who underwent CS, various types of cardiac surgery done during the study period, demographic information, associated comorbidities, various types of NC, postoperative data and various spectrum of computed tomography (CT) findings in the brain. Results: A total of 12,896 adult and pediatric cardiac surgeries were performed at our institute. Out of these, 1115 patients (8.6%) underwent CT brain for suspected neurological injury. A total of 215 patients (1.6%) had a positive finding on their NCCT head. Out of 215 patients, 148 (68.9%) were adult patients, whereas 67 (31.1%) were pediatric patients. A total of 156 (72.5%) patients had ischemic infarction (stroke), whereas hemorrhagic lesions were present in 59 patients (27.4%). The various types of positive CT scan findings were-156 ischemic infarcts (72.5%), 20 intraparenchymal hemorrhages (9.3%), 16 subdural hemorrhage (7.4%), 15 subarachnoid hemorrhage (6.9%), 01 cerebrovascular thrombosis (0.4%), and 07 intraventricular hemorrhage (3.2%). In an adult patient, pattern of ischemic infarct comprised middle cerebral artery (MCA) territory in 42 patients (41.5%), posterior territory in 34 patients (33.6%), anterior cerebral territory in seven patients (7.0%), multi-territory infracts in 11 patients (11.0%) and global ischemia in six patients (6.0%). Intraparenchymal hemorrhage was present in 17 patients (11.4%). In a pediatric subset of patient, the pattern of ischemic infarct included global hypoxic injury (GHI) in 30 patients (54.5%), posterior cerebral artery territory in nine patients (16.3%), MCA territory in eight patients (14.5%), multi-territory involvement in five patients (9.0%), and anterior cerebral artery territory in three patients (5.4%). In the hemorrhage group, five patients (7.4%) developed subarachnoid hemorrhage (SAH). Conclusion: In an adult patient, subset MCA territory infarcts were common in the infract group, whereas intra parenchymal haemorrhage (IPH) in the hemorrhage group. In the pediatric patient subset, GHI was common in infract group and SAH in hemorrhage group. Moreover, NCCT of the head is very useful in diagnosing early postoperative neurological complications in cardiovascular surgeries and managing the complications accordingly.