gms | German Medical Science

Objective: Postoperative administration of low molecular weight heparin (LMWH) in patients with chronic subdural hematoma (cSDH) has been discussed controversially. Although LMWH may have beneficial systemic effects in this population, the rate of hematoma recurrence might increase. The goal of this study was to investigate the impact of postoperative administration of LMWH on residual hematoma size and recurrence rate of cSDHs.

Method: A cohort of 136 patients with cSDHs operated over 18 months was evaluated retrospectively. In the study period the postoperative administration of LMWH was at the discretion of the treating surgeon. Therefore patients were divided into a non-heparin (NH) and a heparin group (H). All patients received post-operative imaging four weeks after surgery or earlier in case of clinical deterioration. The null hypothesis stated that there was no difference at imaging with respect to residual hematoma depth and no difference regarding the need of further operation. Data were collected from hospital charts, outpatient clinic protocols and the PACS (picture archiving and communication system). Groups were compared using Chi squared test or Fisher test. Odds Ratio (OR) with confidence intervals (CI) and Absolute Risk Reduction (ARR) were calculated. Significance was set at P <0.05.

Results: Of n=105 (100%) included patients, n=50 (47.6%) received no heparin (NH), n=55 (52.4%) received heparin post-operatively (H). Eleven patients (22%) in group NH and n=15 (27.3%) patients in group H underwent surgery for hematoma recurrence or presented with a residual hematoma deeper than one third of the initial hematoma size. The OR to suffer from important residual hematoma or to need secondary surgery was 1.21 (95% CI 0.49 to 2.99), P=0.68, the ARR was –0.06. N=9 (18%) patients in Group NH and n=6 (10.9%) patients in Group H required revision surgery (OR 0.56, 95% CI 0.18 to 1.7, P=0.3, ARR 0.06). Complications included one stroke, two TIAs, two cases of pulmonary embolism and one case of myocardial infarction (no statistically significant group differences). Two patients died.

Conclusions: The administration of LMWH in patients with cSDH does not lead to a clinically significant increase in the revision rate for recurrent or residual hematoma. Since postoperative systemic vascular complications are common in this patient population, the administration of LMWH was instituted as a treatment standard as a result of the study.