Evaluation of pain following supratentorial craniotomy

Abstract

Background: Craniotomy is considered less painful than other surgical procedures and supratentorial surgeries are thought to be the least painful among them. We studied the intensity of pain in the postoperative period following a supratentorial craniotomy while using oral paracetamol as the sole analgesic. The effect of temporalis muscle incision on the intensity of pain was also studied. Methods: In a prospective study over 6 months, 43 patients with a pre-operative Glasgow coma scale (GCS) score 15/15, aged>16 years who underwent a supratentorial craniotomy and were admitted to neurosurgical ICU were included in the study. Patients with a postoperative GCS score of<15 on admission to the ICU were excluded from the study. All patients received oral paracetamol for pain relief. Postoperative pain scale was used in the first hour to assess pain objectively. Visual analogue scale was used thereafter to record pain at 8, 12, 24 and 48h post-craniotomy. Patients were familiarised with these scales preoperatively. Postoperative pain scores were compared with preoperative scores using paired T test, whereas significance of temporalis muscle involvement in incision for increased post-craniotomy pain was evaluated using Fischer's exact test. Results: Inadequate analgesia was complained of by 63% (n=27) patients in the first 12h postoperatively. However, severe pain was present only in 12% (n=5) of patients. Incidence of pain decreased thereafter at 24 and 48h. Twenty-seven percent (n=12) patients were free of pain at all study periods. Fifty percent (n=3) of patients who complained of significant pain beyond 12h developed postoperative complications. Incision of temporalis muscle was not associated with a significant increase in severity of postoperative pain. Conclusion: Pain following craniotomy is adequately addressed in only about 27% of patients with oral paracetamol. However, the long-term analgesic effect is satisfactory. Persistence of pain of moderate or severe intensity 24h after a craniotomy could suggest an impending postoperative complication.