Addition of magnesium sulfate to bupivacaine improves analgesic efficacy after tonsillectomy: A randomized trial and a CONSORT analysis

Eur Ann Otorhinolaryngol Head Neck Dis. 2022 Nov;139(6):327-331. doi: 10.1016/j.anorl.2022.04.007. Epub 2022 Jun 7.

Abstract

Objectives: The main objective of this study was to compare the wound infiltration (peritonsillar fossa) of magnesium sulphate combined with bupivacaine, bupivacaine alone and saline solution on post-tonsillectomy pain in children. The accessory objectives were to evaluate the effect of magnesium sulphate infiltration on prevention of laryngospasm and occurrence of nausea/vomiting.

Methods: This study is a prospective; double blinded and randomized clinical trial. Seventy-five children undergoing tonsillectomy were enrolled. Patients were randomized into three groups using closed envelop technique. Group 1 (N=24) received saline solution (NaCl), group 2 (N=25) received 0.25% bupivacaine (1mg/kg) and group 3 received magnesium sulphate (5mg/kg) and 0.25% bupivacaine (1mg/kg) after tonsillectomy using three-point technique. Pain was evaluated using mCHEOPS scale. The occurrence of laryngospasm, nausea and vomiting was monitored.

Results: The mCHEOPS scores of the group 3 were significantly lower than those of the group 2 and 1 (P<0.001). Time to first analgesic administration was longer for the group 3 than for the groups 2 and 1 (P<0.001). The mean consumption of additional analgesic drugs was lower for the group 3 than the other groups (P<0.001). There were no episodes of laryngospasm in the group 3 in comparison with the other groups. The difference of the incidence of nausea and vomiting was not statistically significant (P=0.628).

Conclusion: The adjunction of magnesium sulphate to bupivacaine proved to provide more efficient pain control than bupivacaine alone. However, the small number of participants and the absence of sampling at the P level of 0.005 do not allow to conclude with absolute certainty.

Keywords: Bupivacaine; Children.; Magnesium Sulfate; Pain; Tonsillectomy.

Publication types

  • Randomized Controlled Trial

MeSH terms

  • Analgesics* / therapeutic use
  • Anesthetics, Local / therapeutic use
  • Bupivacaine* / therapeutic use
  • Child
  • Double-Blind Method
  • Humans
  • Laryngismus / complications
  • Laryngismus / drug therapy
  • Magnesium Sulfate* / therapeutic use
  • Nausea / complications
  • Nausea / drug therapy
  • Pain Measurement / adverse effects
  • Pain Measurement / methods
  • Pain, Postoperative / drug therapy
  • Pain, Postoperative / etiology
  • Pain, Postoperative / prevention & control
  • Prospective Studies
  • Saline Solution / therapeutic use
  • Tonsillectomy* / adverse effects
  • Tonsillectomy* / methods

Substances

  • Analgesics
  • Anesthetics, Local
  • Bupivacaine
  • Magnesium Sulfate
  • Saline Solution