Administration of preemptive analgesia by diclofenac to prevent acute postcraniotomy headache

Postcraniotomy headache (PCH) is a frequent perioperative complication in neuroanesthesia. The aim of the present work was to assess the incidence of PCH and to test the efficacy and safety of preoperatively administered diclofenac.

Patients undergoing craniotomies for intracranial tumor resections were enrolled. In the case group 100 mg diclofenac p.o. one hour prior to surgery was used as a preemptive analgesic along with infiltration of the surgical site with a combination of lidocaine and epinephrine. In controls only surgical site infiltration was used. VAS scores were assessed preoperatively, on the day of surgery (DoS), on the 1st and 5th postoperative days.

We have found that PCH of any severity is between 50-90% during the first five days after surgery. The number of cases characterized as "no pain" significantly decreased in the early postoperative period, but remained in both groups still higher on the 5th postoperative day than observed preoperatively. In both groups, the number of headaches characterized as mild pain remained relatively stable and substantial increases in case numbers were observed in moderate and severe headaches, showing a declining tendency over time in the postoperative period. A significant effect of diclofenac pretreatment was observed compared to controls on DoS (chi2: 10.429, p<0.015), on the 1st (chi2: 8.75, p<0.032) and 5th postoperative days (chi2: 14.3, p<0.002).

The relatively low incidence of severe PCH on day five in the diclofenac group may indicate that preoperatively administered diclofenac effectively reduces postcraniotomy headache. A randomized study is encouraged to test this hypothesis.