Currently, there remains a lack of evidence to guide the optimal timing of anticoagulant re-initiation for stroke prevention in atrial fibrillation following cSDH evacuation.
Nassiri et al. conducted a survey of Canadian neurosurgeons and stroke neurologists using a novel self-administered questionnaire utilizing clinical cases that included questions on clinical experience, practice setting, practice patterns and perceptions on stroke/bleeding risk with anticoagulation re-initiation after cSDH evacuation. The instrument was evaluated for clinical sensibility by five neurosurgeons, neurologists, and intensivists.
The response rate after 4 mailings was 40% for neurosurgeons (55/136) and 21% for stroke neurologists (26/122). Almost all participants would restart anticoagulation for stroke prevention in atrial fibrillation following cSDH evacuation (91.8% in low-risk patients, 98.6% in high-risk patients). Time to re-initiation of anticoagulation varied considerably, particularly for high-risk patients where 36% of participants would restart anticoagulation within 1wk of surgery, 44% between 1-4wks after surgery, and 19% after 4wks post-operatively. The perceived risk of stroke and SDH re-accumulation varied considerably among participants and was dependent on timing of anticoagulation re-initiation.
There is considerable variation in current practice patterns and perceived risks of embolic and hemorrhagic complications with anticoagulation re-initiation after cSDH evacuation. These results demonstrate clinical equipoise that warrant further targeted investigation in large-scale randomized controlled trials 1).
Between January 2008 and April 2015, 36 patients with warfarin-related unilateral CSDH and 151 patients with ordinary unilateral CSDH were enrolled in this study. Patients taking warfarin were managed homogeneously according to the study protocol, and the usual dosage of warfarin was resumed within 2 or 3 days of burr-hole drainage to reach a target international normalized ratio (INR) of 2.1. The primary outcome, defined as recurrent CSDH requiring repeated burr-hole drainage within 3 months of the initial surgery, was compared between the two groups.
The primary outcome was observed in 4 (11%) of the 36 patients taking warfarin and in 18 (12%) of the 151 ordinary patients. After propensity score matching, the primary outcome was observed in 3 of 33 patients (9%) in the matched warfarin cohort and 11 of 74 patients (15%) in the matched ordinary cohort. When the results were analyzed using the generalized estimating equation, no significant difference was observed in the rate of recurrent CSDH between the 2 groups (P = 0.411). In addition, we found that recurrent CSDH was not related to postoperative international normalized ratio levels (P = 0.332).
There was no definitive association between postoperative early warfarin resumption and the recurrence rate of CSDH. Patients with warfarin-related CSDH and a strong indication for anticoagulation can be managed by resuming warfarin within 3 days of burr-hole drainage 2).
The aim of a international survey was to investigate the current management of patients undergoing surgery for chronic subdural hematoma (cSDH) treated with low-dose acetylsalicylic acid (ASA).
They administered a survey via e-mail to neurosurgeons with questions relating to the surgical treatment of cSDH, emphasizing their practices with patients treated with low-dose ASA.
They received 157 responses, with a response rate of 22.4%. Almost 80% of the responders discontinue ASA treatment at least 5 days before surgery and 80.7% resume treatment after 5 days or more, and 27.6% discontinue treatment for at least 30 days. The main factor influencing ASA resumption time is the indication for ASA (54.5%), and postoperative imaging is concluded in 71.7%, Postoperative thrombosis prophylaxis is administered by 60% of the responders, and 50% apply it 24 hours after surgery. Almost 95% of the responders believe that better evidence is needed for the management of patients with cSDH treated with ASA. Guidelines for these patients exist in only 24.3% of the institutes.
Most neurosurgeons discontinue ASA treatment for at least 7 days in the perioperative period of surgical evacuation of cSDH, even though recent studies show that early ASA resumption might be safe. Thrombosis prophylaxis is administered by only 60%, even though patients with cSDH are at high risk of developing thromboembolic complications. Better evidence and guidelines are warranted because the incidence of patients with cSDH under the treatment of ASA is increasing 3).
Databases including Pubmed, Embase and Cochrane were searched for patients presenting with CSDH on anticoagulant or antiplatelet medication. Ten studies were included to analyze the association between the use of AT and PR: The meta-analysis showed that the use of AT, both anticoagulants (OR=2.20, 95%CI [1.45, 3.33]; P=0.0002) and antiplatelets (OR=1.64, 95%CI [1.17, 2.30]; P=0.004), could increase the PR rate. Two studies were included to analyze the relationship between the resumption of AT and postoperative complications. The meta-analysis showed that after the patients on AT resumed their medication, the risk of PR did not increase (OR=0.33, 95%Cl [0.13, 0.80]; P=0.01), and the occurrence of thromboembolism events had no statistical significance (OR=1.30, 95%CI [0.26, 6.50]; P=0.75). This meta-analysis demonstrated that AT were risk factors for the recurrence of CSDH. Recommencement of AT did not appear to increase the risk of postoperative hemorrhage, and could reduce the risk of thromboembolism. Thus, appropriate postoperative resumption of anticoagulants or antiplatelets may be safe. Still, more evidence is needed to answer the question about whether and how to resume AT 4).
Patients with a history of preoperative AT experienced thromboembolic complications significantly earlier than those patients without AT, which peaked at 3 days postoperatively with no increase in hemorrhage risk when AT was restarted. Cursory evidence is presented that shows resuming AT early following the surgical evacuation of cSDH at 3 days postoperatively may be safe. However, much larger prospective studies are required prior to providing any definitive recommendations regarding the optimal timing and method of resumption of individual agents 5).
Restarting warfarin therapy does not need to be withheld for more than 3 days after burr hole drainage, particularly in patients with a high thromboembolic risk 6).