Adjuvants to Conventional Management of Postdural Puncture Headache Following Obstetric Surgery Under Spinal Anesthesia: Mirtazapine vs. Sumatriptan.

Background: Postdural puncture headache (PDPH) is a debilitating, life-altering complication of the administration of obstetric spinal anesthesia (SA). The lack of evidence-based treatment for PDPH necessitates the implementation of new treatment modalities. Mirtazapine is a noradrenergic and specific serotonergic antidepressant that has been used as a prophylactic treatment for chronic tension-type headaches. Few previous studies have assessed the efficacy of sumatriptan in the treatment of PDPH.

Objectives: The purpose of this study was to assess the hypothesis that an adjunctive therapy that involved adding mirtazapine or sumatriptan to conventional management (CM) would be more effective in reducing the incidence of refractory PDPH after obstetric surgery under SA than would CM alone.

Study design: A prospective randomized study.

Setting: This study was carried out at Ain-Shams University Maternity Hospital.

Methods: Two hundred and ten American Society of Anesthesiologists (ASA) physical status II  women who complained of PDPH after obstetric SA were randomly allocated to one of 3 groups. Each group consisted of 70 women. The intervention treatment for every group was continued for 3 days, as was the CM of PDPH. Every day at 8 p.m., patients in the mirtazapine group (the M-group) took 30 mg mirtazapine tablet, patients in the sumatriptan group (the S-group) took 50 mg sumatriptan tablet, and patients in the control group (the C-group) took placebo tablets. The primary outcome was the incidence of refractory headache 72 hours after the ingestion of the first dose of the intervention drugs. The incidences of side effects of the study drugs, the hospital length of stay (LOS), and the patient satisfaction score were secondary outcomes.

Results: Patients in the C-group had higher means of headache intensity, lower rates of complete response to medical treatment, more increased incidences of refractory PDPH 72 hours after intervention, and a greater need for epidural blood patches than did patients in either of the intervention groups (P < 0.001), with comparable efficacy between the M- and S-groups (P > 0.05). Incidences of nausea, vomiting, and the need for antiemetics were least frequent in the M-group (P < 0.001). More patients in the C-group had a high prevalence of photophobia and neck stiffness than did patients in the other 2 groups (P < 0.001). Meanwhile, patients in the M- and S-groups had lower hospital LOS and higher patient satisfaction scores (P < 0.001), with no significant differences between the intervention groups (P > 0.05).

Limitations: This was a single-center study. This study did not determine the optimal dose of mirtazapine.

Conclusions: Adding either mirtazapine or sumatriptan to the CM of PDPH following obstetric SA was associated with lower means of headache intensities, higher rates of complete response to medical treatment, and decreased incidence of refractory headaches. As an antiemetic drug, mirtazapine was found to be effective, inexpensive, safe, well-tolerated, and capable of being used on an outpatient basis.