Initial Rotterdam CT score may predict prognosis of the patients after unilateral decompression craniectomy for treating severe traumatic brain injury

Abstract

Objective To identify the factors enhancing the contusive brain hemorrhage following unilateral decompression craniectomy in patients with severe traumatic brain injury (TBI),and to explore the relationship between the initial Rotterdam CT score and clinical outcomes.Methods A prospective study of 291 consecutive patients with TBI admitted from Jan 2008 through Dec 2012 was carried out.Patients treated with unilateral decompression craniectomy were enrolled for study.Patients without preoperative or postoperative cranial CT imaging were excluded.Of them,235 patients were followed up.Gender,age,the causes of injury,preoperative general condition including Glasgow Coma Scale (GCS) score,pupillary response,laboratory data and the initial CT scans before operation,contusion hematoma size in CT scans following operation and Glasgow Outcome Scale (GOS) score were recorded.With t test,x2 test and nonparametric rank sum test,differences in the above listed variables were compared between patients with enlarged hematoma size group and those without change in hematoma size.A Classification And Regression Tree (CART) was used to predict the size of hematoma.Correlation analysis was used to find the relationship between the Rotterdam CT scores and GOS scores.Results The differences in age (t =2.034,P =0.043),first Rotterdam CT score (Z =4.838,P ＜ 0.01),GCS score (Z =4.440,P ＜ 0.01),pupillary response (Z =3.235,P =0.001),the length of time elapsed between the trauma occurred and the decompressive craniectomy (Z =3.874,P ＜ 0.01),glucose level (Z =3.880,P ＜ 0.01) and cerebrum hernia magnitude (Z =2.529,P =0.012) were significant between the patients with hematoma expanded (n =120) and those without change in hematoma size (n =115).The results of the CART indicated that Rotterdam score got from the initial head CT,glucose level and the length of time elapsed between trauma occurred and decompressive craniectomy were strong predictors of the risk for expanded hemorrhagic contusions following decompressive craniectomy.Both age and size of the removed bone-flap also could predict the risk of postoperative expansion of hemorrhagic contusions.The overall predictive accuracy of the CART model was 83.3％.Correlation analysis results indicated that Rotterdam CT score was negatively correlated with GOS (r =-0.333,P ＜ 0.01).Conclusions Initial Rotterdam CT scores,glucose level and the length of time between trauma and decompressive craniectomy may predict the risk of contusions expansion following decompressive craniectomy.Rotterdam CT score was negatively correlated with GOS. Key words: Traumatic brain injury ; Brain hemorrhage, Traumatic ; Subarachnoid hemorrhage, traumatic ; Rotterdam CT score ; Decompressive craniectomy; Prognosis ; Classification and regression tree; Glasgow outcome scale