Background: Dexmedetomidine (DEX) is a selective alpha-2 adrenergic agonist with several desirable pharmacologic properties for sedation of patients with risk of ventilatory dysfunction (1).
Case report: We report a case of sedation with DEX for awake fiberoptic orotracheal intubation of a morbidly obese patient. A 42-year-old male, BMI: 74 (237 kg, 179 cm), with known severe OSAS and poorly controlled hypertension was scheduled for the placement of a gastrostomy tube. Premedication was atropine 1mg, ranitidine 50mg and metoclopramide 10mg. The patient received nasal oxygen at 4lt/min and conventional monitoring. Topical anaesthesia was achieved in oropharynx, hypopharynx and glottis using lidocaine 8% spray. DEX infusion started at 1.5 mcg/kg/10 minutes, based on estimated ideal weight of 100kg. Infusion of DEX continued at 0.7 mcg/kg/h. During awake intubation, Ramsay sedation status was 2-3, SatO2 remained over 96%, and patient was hemodinamically stable.
After intubation was achieved (5min) DEX infusion was stopped and the procedure was carried on under general anesthesia (desflurane/remifentanil/rocuronium) adding TOF monitoring. Patient received suggamadex reversal before eduction. No opioids were needed either intra or postoperatively. Postoperatory was uneventful.
Discussion: As anaesthesiologists, we face the challenge of providing adequate sedation for airway management of patients at high risk of ventilatory or airway complications (1). Alpha 2- agonists have been associated with good sedation scores and minimal respiratory depression (2,3)
Conclusions: DEX may offer a beneficial profile for sedation of obese patients, allowing confort during fibrobronchoscopy, preservation of ventilatory function and reduction in the need for opioids. Dosage for obese pacients is still unclear. Future studies should focus in the pharmacologic and pharmacokinetic profile of DEX on this population to minimize the risk of adverse effects.
1. Ramsay MA, Saha D, Hebeler RF: Tracheal resection in the morbidly obese patient: the role of dexmedetomidine.
J Clin Anesth. 2006 Sep;18(6):452-4.
2. Hu R, LiuJX, Jiang H: Dexmetomidine vs remifentanil sedation during awake fiberoptic nasotracheal intubation: a double-blinded randomized controlled trial.
J Anesth. 2013 Apr;27(2):211-71.
3. Venn RM, Hell J, Grounds RM: Respiratory effects of dexmedetomidine in the surgical patient requiring intensive care.
Critical Care 2000; 4:302-8