Comparison Between Lidocaine Inhalation and Intravenous Dexamethasone in Reducing Postoperative Sore Throat Frequency After Laryngeal Mask Insertion.

backgroundThe frequency of postoperative sore throat (POST) after laryngeal mask airway insertion (LMA) was relatively high. Lidocaine might reduce the pain and inflammatory response. Additionally, inhalation form might result in a better distribution, which results in a better airway analgesia and minimal systemic effect.

objectivesTo compare the incidence of sore throat post LMA insertion after 1.5 mg/kg of lidocaine inhalation and 10 mg of intravenous dexamethasone.

methodsThis was a single-blinded randomized clinical trial, which included 128 patients who underwent ophthalmic surgery under general anesthesia with LMA insertion. Inclusion criteria were individuals 18 - 65 years old, ASA 1 or 2, Mallampati class I or II, and no sore throat before surgery. After University of Indonesia Research Ethical Committee approval and informed consent, all subjects were randomly divided into two groups: lidocaine inhalation group, which would receive lidocaine inhalation 2% 1.5 mg/kg (additional NaCl 0.9% until total 6 mL volume) and intravenous 2 mL NaCl 0.9%, and dexamethasone group, which would received NaCl 0.9% inhalation (6 mL volume) and dexamethasone 10 mg intravenously 10 minutes before LMA insertion. POST incidence and pain severity assessment were done 2 hours postoperatively. Statistical analysis were done with SPSS version 21.

resultsThere were 10.9% of subjects in the lidocaine inhalation group and 9.4% subjects in the dexamethasone group who suffer from POST postoperatively (P > 0.05). The median of POST pain in the lidocaine inhalation group was 0 (0 - 1), whereas in dexamethasone group it was 0 (0 - 3). This study did not find any side effects on both groups.

conclusionsLidocaine inhalation 1.5 mg/kg was proportional to intravenous dexamethasone 10 mg in reducing the incidence and severity of POST after LMA insertion.