Introduction: We aimed to identify surgery specific and patient specific prognostic factors related to developing unfavourable outcomes following burrhole evacuation of chronic subdural haematomas (CSDH).
Methods: A retrospective cohort of patients undergoing evacuation of CSDH at a single institution was established from September 2010-October 2014. Primary endpoint was the dichotomized score on a modified Rankin scale at 6 months follow-up (‘favourable outcome’ score 0-1 or ‘unfavourable outcome’ score 2-6). A logistic regression analysis was performed to model and predict the determinants related to outcome. A scoring system was made to predict ‘favourable vs. unfavourable’ outcomes.
Results: 120 patients were included in this study (mean age 66.1±15.2 years). Logistic regression analysis showed that age>75 (OR 7.1, 95%CI 1.7-29.0, p=0.007), midline shift 10-20mm (OR 3.4, 95%CI 1.0-11.4, p=0.04), disorientation (OR 24.1, 95%CI 3.1-189.0, p=0.002), motor function deficit (OR 4.9, 95%CI 1.5-15.9, p=0.008) before surgery were unfavourable prognostic factors. Duration of in-patient stay, sex, ASA, side of haematoma, coagulation status were not predictive of developing an unfavourable outcome. Using the significant prognostic factors that predicted an unfavourable outcome, a scoring system was devised (1. Age:<60 - 3 points, 60-75 - 2 points, >75 - 1 point; 2. GCS:<8 - 0 points, 8-13 - 1 point, >13 - 2 points; 3. Thickness of haematoma:>3cm - 0 points, 1-3cm - 1 point, <1cm - 2 points; 4. Mid-line shift:>2cm - 0 points, 1-2cm - 1 point, <1cm - 2 points; 5. Motor function:Not normal - 1 point, normal - 2 points; 6. Orientation:disorientated - 1 point, orientated - 2 points). ROC curves were constructed to predict favourable vs. unfavourable outcomes. A score of 9 and above showed a favourable outcome.
Conclusions: Unfavourable outcomes are predicted by age>75, mid-line shift >1cm, drop in GCS on verbal or motor score from normal. A scoring system has been devised to predict outcome.
Patient Care: The scoring system can help clinicians to decide whether the patient may need further rehabilitation vs. sending the patient back home. The scoring system also looks at the role of conservative vs. surgery in patients with certain specific prognostic factors.
Learning Objectives: By the conclusion of this session, participants should be able to: 1) Describe the importance of identifying risk factors that lead to poor prognosis in this cohort of individuals, 2) Discuss, in small groups, further management of patients who have unfavourable predictive outcomes, 3) Identify an effective treatment using a scoring system that is practical and statistically reliable to estimate clinical outcome of CSDHs.