[Satisfactory Sedation for a Morbidly Obese Woman by Dexmedetomidine Dosed on the Basis of Total Body Weight under Spinal Anesthesia ; A Case Report].

ABSTRACT

A 45-year-old morbidly obese woman (body mass index 51.9) was scheduled for right knee arthroscopic synovectomy. We selected spinal anesthesia in order to avoid difficult ventilation or intubation during anes- thetic induction of general anesthesia. As she strongly requested unawareness during operation, we decided to sedate her with dexmedetomidine(DEX), a sedative drug which has little possibility to cause upper airway obstruction and respiratory depression. Dose of DEX was determined based on total body weight (TBW) instead of ideal body weight To achieve adequate sedation, DEX was titrated by monitoring Ramsay sedation score (RSS), and was discontinued 10 minutes before the end of operation. She was well sedated dur- ing the operation but developed minimal upper airway obstruction and respiratory depression. She showed a good recovery profile when discharged from the oper- ating room. She was very satisfied with the anesthetic management The similar patient's satisfaction was also obtained at the opposite knee joint operation per- formed using the same anesthetic management Conse- quently, DEX infusion based on TBW appears to be suitable to sedate a morbidly obese patient.