Comparative evaluation of nebulized versus intravenous dexmedetomidine on intubating conditions during awake fiberoptic nasotracheal intubation.

BACKGROUND: There is a search for an ideal agent to facilitate awake fiberoptic intubation (AFOI). Dexmedetomidine is a selective α2 agonist which can be administered through intravenous, intramuscular, buccal, intranasal & inhalational routes. It provides good intubation conditions without oxygen desaturation but may cause hypotension and bradycardia when administered intravenously. Hence, alternative routes of administering dexmedetomidine which may improve its safety profile are worth exploring. METHODS: In this randomised, controlled, double-blind trial, 46 ASA I/II adult participants scheduled for elective ENT surgery were randomly allocated to Group ND (Nebulised Dexmedetomidine) (n = 23) to receive nebulisation with dexmedetomidine 1µg.kg-1 and Group ID (Intravenous Dexmedetomidine) (n = 23) to receive intravenous dexmedetomidine 1µg.kg-1 before AFOI. All the patients received injection midazolam 1 mg i.v. as premedication before anaesthesia was initiated. The primary outcome was the cough score. The secondary outcomes were the RSS, SAYGO boluses, post-intubation score, hemodynamic parameters, recall of the procedure, patient satisfaction score and any side effects. RESULTS: The cough score was significantly lower in nebulized group (2.43 ± 0.992 vs 3.52 ± 1.082) with p = 0.001. RSS(3.30 ± 0.926 vs 4.22 ± 1.126; p = 0.004), number of SAYGO boluses required (2.74 ± 0.864 vs 3.57 ± 1.161; p = 0.009) & the post intubation score (1.48 ± 0.593 vs 2.17 ± 0.778; p = 0.001) were also significantly lower in nebulized group. CONCLUSIONS: Nebulisation with dexmedetomidine results in desirable degree of sedation and better tolerance of the procedure with adequate attenuation of the haemodynamic responses to intubation.

Comparative evaluation of gastric pH and volume in morbidly obese and lean patients undergoing elective surgery and effect of aspiration prophylaxis.

INTRODUCTION: The anesthetic management of patients with morbid obesity is challenging. There is no consensus on the routine use of aspiration prophylaxis in morbidly obese patients undergoing elective surgery. AIM: The aim of this study is to assess the risk of pulmonary aspiration and effect of premedication with ranitidine and metoclopramide on gastric pH and volume in morbidly obese and lean patients. METHODS: Gastric volume and pH were measured in 3 groups of 20 patients each: group I (lean, no aspiration prophylaxis), group II (morbidly obese, no aspiration prophylaxis), and group III (morbidly obese; tablet ranitidine, 150 mg; and tablet metoclopramide, 10 mg administered the night before and 2 hours before surgery). Patients with critical gastric volume >25 mL and critical pH <2.5 (Roberts and Shirley criteria) were considered to be at risk for pulmonary aspiration. RESULTS: The percentage of patients with gastric volume >25 mL and pH <2.5 was 5%, 30%, and 0% in groups I, II, and III, respectively. Statistically significant difference existed between groups I and II (P = .04) and groups II and III (P = .006). Premedicated morbidly obese and lean patients were comparable (P = .46). CONCLUSION: Morbidly obese patients undergoing elective surgery are at a higher risk for regurgitation and pulmonary aspiration when compared with lean patients. Preoperative aspiration prophylaxis decreases gastric volume and increases gastric pH and thus should be routinely prescribed.