Subperiosteal versus Subdural Drain After Burr-hole Drainage Under Blood Thinners: A Subanalysis of the cSDH-Drain RCT

Optimal drainage time after evacuation of chronic subdural haematoma (DRAIN TIME 2): a multicentre, randomised, multiarm and multistage non-inferiority trial in Denmark

BACKGROUND

Postoperative drainage after surgical evacuation of chronic subdural haematoma reduces the risk of recurrence, but the optimum drainage time is uncertain. We aimed to investigate the shortest possible drainage time without increasing the haematoma recurrence rate.

METHODS

We conducted a randomised, multi-arm and multistage non-inferiority trial at four neurosurgical centres in Denmark. We enrolled adult patients (aged ≥18 years) with symptomatic chronic subdural haematoma. All patients were treated according to the national standard practice with a burr hole above the maximum width of the haematoma. Patients were randomly assigned in a 1:1:1 ratio via a centralised web server to receive 6 h, 12 h, or 24 h of postoperative passive subdural drainage. Randomisation was done by an independent on-call neurosurgeon and was masked until 6 h after surgery. The primary outcome was symptomatic haematoma recurrence at 3 months after surgery; the rate of recurrence was assessed in a regression model for non-inferiority testing, with no missing data. Personnel assessing the primary outcome were masked to group allocation. Non-inferiority was assessed with a prespecified margin of 7%, in a modified intention-to-treat population-defined as patients with randomly assigned treatment excluding those withdrawing from study participation after randomisation, or experiencing acute rebleedings or accidental drain removal. This trial is registered with ISRCTN (number 15186366); the trial was stopped after the first interim analysis on the advice of an independent safety advisory committee.

FINDINGS

Between March 1, 2021, and June 30, 2022, 347 patients were enrolled and 331 were followed up to 3 months, 105 were assigned to 6 h of drainage, 111 to 12 h of drainage, and 115 to 24 h of drainage. At admission, 83 (25%) participants were women and 248 (75%) were men, mean age was 75·7 years (SD 10·5), median modified Rankin Scale score was 4 (IQR 3-5), and median Glasgow Coma Scale score was 15 (IQR 14-15). At 3 months after surgery, haematoma recurrence was reported in 28 (27%) of 105 patients who were assigned to 6 h drainage (predicted haematoma recurrence rate 27·0%, 95% CI 18·5 to 35·4), 22 (20%) of 111 assigned to 12 h drainage (19·5%, 12·0 to 27·0), and 12 (10%) of 115 assigned to 24 h drainage (10·4%, 4·8 to 16·0). The risk of haematoma recurrence was increased by 16·5 percentage points (95% CI 6·5 to 26·6) in patients drained for 6 h compared with 24 h, and by 9·1 percentage points (-0·4 to 18·5) in patients drained for 12 h compared with 24 h. Therefore, non-inferiority of 6 h and 12 h of drainage to 24 h of drainage was not established. 20 patients had died by 3 months, seven in the 6 h group, eight in the 12 h group, and five in the 24 h group. The most frequent known causes of death were haematoma recurrence (three in 12 h group), comorbidity (three in 12 h group), and pneumonia (one each in 6 h and 12 h groups, two in 24 h group). The most frequent complication was postoperative infection, reported in 20 (20%) patients in the 6 h group, 25 (23%) in the 12 h group, and 19 (17%) in the 24 h group. The most common infection source was the urinary tract.

INTERPRETATION

Patients surgically treated for symptomatic chronic subdural haematoma and postoperatively drained for 6 h or 12 h had higher rates of haematoma recurrence than did patients drained for 24 h. The findings from this non-inferiority trial provide evidence to support 24 h of postoperative drainage as the standard drain time when a fixed drain time approach is used. To provide solid evidence of generalisability of the results to countries other than Denmark, a multinational randomised controlled trial will be needed.

FUNDING

None.

Comparative analysis of safety and efficacy in subperiosteal versus subdural drainage after burr-hole trephination for chronic subdural hematoma

PURPOSE

The treatment of choice for chronic subdural hematoma (CSDH) has been established as burr-hole trephination with drain insertion; however, controversy remains over the best place for the drainage catheter. In this study, we compare the safety and efficacy of a subperiosteal drain (SPD) with that of a subdural drain (SDD) after one burr-hole trephination for CSDH.

METHODS

This retrospective and comparative study includes all CSDH patients treated with burr-hole trephination at our institution between January 2015 and December 2019. 59 patients were treated with SPD insertion (SPD group), and 203 patients were treated with SDD insertion (SDD group).

RESULTS

The median hematoma thickness of the SPD group within 24 h after surgery was significantly thicker than that of the SDD group (9.5 mm vs. 7.5 mm, p = 0.003), but the midline shifting of the SPD group did not differ from that of the SDD group (3.8 mm vs. 3.5 mm, p = 0.280). The recurrence rate in the SPD group did not differ significantly from that in the SDD group (13.2% vs. 8.5%, p = 0.351). The frequency of bleeding events after surgery also did not differ significantly (5.1% vs. 3.5% p-value = 0.636). In contrast to surgery-related morbidities, medical morbidities such as pneumonia were significantly higher in the SDD group (4.4% vs. 0.0%, p = 0.044). The all-cause mortality rates during the perioperative period did not differ between the two groups (5.1% vs. 3.4%, p = 0.848).

CONCLUSION

Our findings may suggest that burr-hole trephination with SPD insertion had better surgical feasibility and fewer perioperative complications than SDD insertion. The type of anesthesia seems to be related with fewer medical complications at perioperative period. Larger, randomized clinical trials focusing not only the drain type but anesthesia type, are needed to validate our findings.

Drain type after burr-hole drainage of chronic subdural hematoma in geriatric patients: a subanalysis of the cSDH-Drain randomized controlled trial

OBJECTIVE

Chronic subdural hematoma (cSDH) occurs more frequently in elderly patients, while older patient age is associated with worse postoperative outcome following burr-hole drainage (BHD) of cSDH. The cSDH-Drain trial showed comparable recurrence rates after BHD and placement of either a subperiosteal drain (SPD) or subdural drain (SDD). Additionally, an SPD showed a significantly lower rate of infections as well as iatrogenic parenchymal injuries through drain misplacement. This post hoc analysis aims to compare recurrence rates and clinical outcomes following BHD of cSDH and the placement of SPDs or SDDs in elderly patients.

METHODS

The study included 104 patients (47.3%) 80 years of age and older from the 220 patients recruited in the preceding cSDH-Drain trial. SPDs and SDDs were compared with regard to recurrence rate, morbidity, mortality, and clinical outcome. A post hoc analysis using logistic regression, comparing the outcome measurements for patients < 80 and ≥ 80 years old in a univariate analysis and stratified for drain type, was further completed.

RESULTS

Patients ≥ 80 years of age treated with an SDD showed higher recurrence rates (12.8%) compared with those treated with an SPD (8.2%), without a significant difference (p = 0.46). Significantly higher drain misplacement rates were observed for patients older than 80 years and treated with an SDD compared with an SPD (0% vs 20%, p = 0.01). Comparing patients older than 80 years to younger patients, significantly higher overall mortality (15.4% vs 5.2%, p = 0.012), 30-day mortality (3.8% vs 0%, p = 0.033), and surgical mortality (2.9% vs 1.7%, p = 0.034) rates were observed. Clinical outcome at the 12-month follow-up was significantly worse for patients ≥ 80 years old, and logistic regression showed a significant association of age with outcome, while drain type had no association with outcome.

CONCLUSIONS

The initial findings of the cSDH-Drain trial and the findings of this subanalysis suggest that SPD may be warranted in elderly patients. As opposed to drain type, patient age (> 80 years) was significantly associated with worse outcome, as well as higher morbidity and mortality rates.