Effect of primary decompressive craniectomy on outcomes in severe traumatic brain injury with mass lesions and the independent predictors for operation decision

Abstract Background: Although operative indications for traumatic brain injury (TBI) have been evaluated, neurosurgeons often face a dilemma of whether or not to remove the bone flap after mass lesion evacuation, and a useful predictive scoring model for which patients should be decompressive craniectomy (DC) has yet to be developed. The aim of this study was firstly to compare the outcomes of craniotomy and DC, and secondly to determine independent predictors and develop a multivariate logistic regression equation to determine whom should perform primary DC in TBI patients with mass lesions.Methods: A total of nine different variables were evaluated. All 245 patients with severe TBI in this study were retrospectively evaluated between June 2015 and May 2019 and all underwent decompressive craniectomy (DC) or craniotomy for mass lesion removal. The 6-month mortality and Extended Glasgow Outcome Scale (GOSE) were compared between DC and craniotomy. By using univariate, multiple logistic regression and prognostic regression scoring equations it was possible to draw Receiver Operating Characteristic curves (ROC) to predict the decision for DC.Results: The overall 6-month mortality in the entire cohort was 11.43% (28/245). DC patients had a lower mean preoperative Glasgow Coma Scale (GCS) (p = 0.01); more patients with GCS of 6 (p=0.007);more unresponsive pupillary light reflex (p< 0.001); more closed basal cisterns (p< 0.001); and more patients with diffuse injury (p=0.025) than craniotomy patients. Given the greater severity, patients undergoing primary DC had higher 6-month mortality than the remainder of the cohort. However, in the surviving patients, the favorable GOSE rate was similar in two groups. We found that pupillary light reflex and basal cisterns were independent predictors for DC decision. Using ROC curve to predict the probability of DC, the sensitivity was 81.6% and the specificity was 84.9%.Conclusion: Our preliminary findings showed that the primary DC may benefit subgroups of sTBI with mass lesions, and unresponsive pre-op pupil reaction, and closed basal cistern to predict the DC decision were useful. These sensitive variables can be used as a referential guideline in our daily practice to decide to perform or avoid primary DC.