Pain on the first postoperative day after tonsillectomy in adults: A comparison of metamizole versus etoricoxib as baseline analgesic

OBJECTIVE: To compare the effect of metamizole versus etoricoxib as baseline analgesic for treating postoperative pain after tonsillectomy. DESIGN: Single centre prospective cohort study. SETTING: Two consecutive cohorts of tonsillectomy patients. PARTICIPANTS: 124 patients (n = 55 treated with etoricoxib, n = 69 with metamizole); median age 30.5 years; 50% women. MAIN OUTCOME MEASURES: Patients rated their pain on first postoperative day using the questionnaires of the German-wide project Quality Improvement in Postoperative Pain Treatment (QUIPS) including numeric rating scales (NRS, 0–10) for pain determination. The influence of preoperative and postoperative parameters on patients' pain was estimated by univariate and multivariate statistical analysis. RESULTS: The demographic parameters showed no differences between the patients in the metamizole group and the etoricoxib group (all p>0.05) with one exception: Patients in the metamizole group had significantly more preoperative pain than patients in the etoricoxib group (p = 0.001). The metamizole group had a mean postoperative pain in activity of 4.4 ± 2.1 and the etoricoxib group of 4.5 ± 2.2. Maximal pain for the metamizole group and the etoricoxib group were 5.6 ± 2.2 and 6.1 ± 1.9, respectively. Pain in activity, maximal pain and minimal pain were not different between both groups (p = 0.652, p = 0.113, p = 0.276, respectively). Patients of the etoricoxib group received more frequently piritramide in recovery room as demand medication (p = 0.046). In the whole cohort, patients with peritonsillar abscess had more preoperative pain in comparison to chronic tonsillitis (p<0.001). Patients under 30.5 years reported higher maximal pain than older patients (p = 0.049). On the other hand, a significant influence of patients’ age on the pain in activity and minimal pain could not be demonstrated (p = 0.368, p = 0.508, respectively). Men reported lower minimal pain than women (p = 0.041). Also, patients with ASA status I had lower minimal pain than patients with higher ASA status (p = 0.019). The multivariate analysis did not show an association between postoperative pain in activity and preoperative counseling on postoperative pain management (p = 0.588, p = 0.174, respectively). Special preoperative counseling on postoperative pain management resulted in lower levels of maximal pain (p = 0.024). Linear regression demonstrated an independent association of higher pain in activity with higher mobility impairment (p = 0.034) and respiratory impairment (p = 0.002). The linear regression of minimal pain identified female gender (p = 0.005) as an independent influencing factor with higher pain levels. In terms of satisfaction, no preoperative pain therapy (p = 0.016) could be found as an independently significant influencing factor with higher satisfaction. CONCLUSION: Etoricoxib does not have an advantage as baseline analgesic for post tonsillectomy pain in comparison to metamizole.