Dexmedetomidine as an adjuvant for Hypotensive Anaesthesia during Functional Endoscopic Sinus Surgery (FESS)

Abstract

Introduction:FESS (Functional Endoscopic Sinus Surgery) is done via endoscope and the area is highly vascular thus it becomes important to minimize bleeding. Hence we require hypotensive anesthesia. Various drugs have been used for the purpose: nitroglycerine (NTG), sodium nitroprusside(SNP),propofol,beta blockers, calcium channel blockers, higher concentrations of inhalational anesthetics etc. Since all these drugs have certain limitations there was a search for safer and more effective drug .Dexmedetomidine, a newer alphaadrenoceptor agonist,fulfills this requirement since it is short acting, has no residual effects, produces sedation and analgesia and reduces mean arterial pressure thereby reducing intraoperative blood loss. Aims: To study the efficacy of dexmedetomidine in providing hypotensive anaesthesia so as to minimize bleeding during endoscopic sinus surgery in a randomized double blind control study. Method:40 patients of ASA grade I/II, aged18-55yrs,scheduled for endoscopic sinus surgery, were randomly allocated into two groups of twenty each by sealed envelope method. Group C: received Normal saline as loading dose of 1mcg/kg intravenously followed by maintenance infusion of 0.6mcg/kg intravenously, Group D: received dexmedetomidine in similar doses. The loading dose was given slowly over 15 minutes. The surgery was started after the loading dose was over. Both the anaesthetist conducting the study and the patient were blinded to the study drug. The amount of blood loss, doses of intravenous& inhalation agents and side effects were studied. Results:The patient characteristics did not differ in bothcontrol(C) and study (D) groups (Table1). Blood losses were lower in group D as compared to group C (p = 0.03).Total dose of fentanyl (p< 0.001),propofol(p <0.001)and isoflurane (p =0.04)were lower in group D as compared to group C. The VAS scores in the immediate postoperative periods were also lower in the group D (p =0.03).The only side effect noted was bradycardia (2patients)which however reverted with discontinuation of the drug.Atropine was not required. Conclusions:Dexmedetomidine is a safe &effective adjuvant for hypotensive anaesthesia to decrease bleeding and thus provide bloodless field during FESS surgery. It also decreases the dose requirements of propofol,fentanyl and isoflurane. It is also an effective analgesic agent.

Efficacy of dexmedetomidine on perioperative morbidity during nasal surgery: A meta‐analysis

“…We also assessed adverse effects such as hemodynamic instability and compared them between the dexmedetomidine and control groups. The administration of a loading dose of dexmedetomidine (1 μg/kg) over 10 minutes, followed by administration of the maintenance dose (range, 0.2 to 0.7 μg/kg/hour) is recommended for patient sedation, regardless of age . The enrolled trials complied with the recommended regimens for maintaining adequate sedation during nasal surgery.…”

“…Outcomes analyzed were intra‐ and postoperative pain; postoperative (24 hours) analgesic requirements (dose of postoperative opioids or nonopioid analgesics); occurrence of postoperative nausea and vomiting (PONV) (incidence or percentage of patients); intraoperative hypotension; intraoperative bradycardia; intraoperative desaturation; occurrence of patient satisfaction (incidence or percentage of patients); and operative blood loss . In the enrolled study for analgesics, one study used diclofenac (nonsteroidal antiinflammatory drug) as the additional analgesic, and the remaining studies used opioids such as tramadol and fentanyl as the additional analgesics. In terms of bradycardia and hypotension, these states were defined as the hemodynamic instabilities to be treated with 0.5 mg of atropine injection or 5 mg of ephedrine injection individually, and were monitored at regular intervals during the operation.…”

“…However, this drug has gained popularity among anesthetists due to its wide spectrum of beneficial effects, including analgesia, lowering of blood pressure, and conscious sedation without respiratory depression. Thus, dexmedetomidine has been used for procedures performed under MAC and also for administering hypotensive anesthesia . The results of several recent studies of the effects of dexmedetomidine on postoperative pain and opioid consumption after postnasal surgeries such as septoplasty and endoscopic sinus surgery are encouraging.…”

Efficacy of dexmedetomidine for perioperative morbidities in pediatric tonsillectomy: A metaanalysis

“…5 Dexmedetomidine, an alpha-2 adrenoceptor agonist, has sympatholytic, sedative, anesthetic, and algesic effects-as well as vasoconstrictive effects. 6,7 During the past few years, dexmedetomidine has reportedly been used in pediatrics as a premedication, a sedation agent used in pediatric intensive care units, an adjunct to inhaled anesthetic agents, and a drug for both prophylaxis and treatment of EA after general anesthesia. 8 The results of several recent studies on the use of perioperative adjuvant dexmedetomidine are encouraging, showing beneficial effects on postoperative morbidities such as pain and agitation in pediatric patients.…”

The effects of dexmedetomidine and tramadol on post‐operative pain and agitation, and extubation quality in paediatric patients undergoing adenotonsillectomy surgery: A randomized trial

“…7 Previous studies have shown that dexmedetomidine could be used as a sedative in the paediatric intensive care unit and as an adjunct to volatile anaesthetics. 2,16 It has also been demonstrated that dexmedetomidine decreases post-operative pain and agitation. 17 For these reasons, dexmedetomidine may be effectively used to treat post-operative pain and agitation in children undergoing adenotonsillectomy surgery using sevoflurane.…”