A Comparison of Dexmedetomidine and Epidural Anesthesia Under General Anesthesia in Patients Undergoing Gastrectomy
A Comparison of Dexmedetomidine and Epidural Anesthesia Under General Anesthesia in Patients Undergoing Gastrectomy
Clinically, combining epidural with general anaesthesia may confer many advantages to patients undergoing major thoracic, abdominal or orthopaedic surgery. Epidural anaesthesia can attenuate sympathetic hyperactivity and the stress response, maintain bowel peristalsis, spare the use of opioids, and facilitate postoperative feeding and physiotherapy. However, establishing epidural anesthesia is not without risks and contraindications, including refusal by the patient, technical failure, unintentional dural puncture, waist and back pain and local anaesthetic toxicity. When neurologic complications do occur, the resulting morbidity and mortality is considerable. Dexmedetomidine is a potent α2-adrenoceptor agonist with an 8 times greater affinity for α2-adrenoceptors than clonidine. This class of agent is known to have sedative, anxiolytic, anti-shivering, analgesic, and anaesthetic sparing effect. In addition α2-adrenoceptor agonists reduce central sympathetic outflow and attenuate the stress response associated with surgery.1 Unlike epidural anaesthesia, dexmedetomidine is easy to administer and no potential for neurological damage. The investigators hypothesize that the dexmedetomidine reduces the stress response of surgery to the similar extent to epidural anaesthesia when used in conjunction with a standard general anaesthesia for abdominal surgery.
Inclusion Criteria:
Exclusion Criteria:
.The subject has known significant renal or hepatic disorders determined by medical history, physical examination or laboratory tests