Application and use of the bispectral index in anaesthesia for head and neck surgery.

 

Papaioannou E., Staikou Ch., Kotsakou D., Lazaridou E., Karousos D., Belivanakis G., Lambadariou A.

 Department of Anaesthesia  “Laikon” Regional General Hospital of Athens.

 

  Bispectral Index (BIS) is a new unique apparatus which provides the anaesthetist with information about how deep is the sedation of the patient. It is a revolution for Anaesthesiology because until today there was no means of evaluating patients’ sedation.

  Aim of this study was to evaluate BIS’s use when providing anaesthesia for head and neck surgery.

  Patients and Methods: We studied 40 patients (26 female and 14 male), aged 16-62 years old, ASA I-II  undergoing elective surgical procedures of head or neck of duration 20-180 minutes under general anaesthesia. Of the study we excluded patients with history of epilepsy. All patients were randomly assigned to 2 groups (A=20, B=20). In group B we applied the BIS apart fron the usual basic monitoring.General anaesthesia was induced with fentanyl 100 μg and propofol  2.5 mg/kg and endotracheal intubation was facilitated by atracurium 0.5 mg/kg in both groups. The maintenance of anaesthesia was achieved with continuous infusion of propofol 150 μg/kg/min in group A and in group B adjusted as necessary to maintain scores 40-60 of the BIS. Both of patient groups received also fentanyl 2 μg/kg as intraoperative analgesic and atracurium as adjusted af the TOF response. We recorded: i) amount of propofole used in every group, ii) recovery time and iii) postoperative sedation and cognitive function after extubation and every 5 minutes during the first hour of staying in the recovery room using Aldrete’s scale.

  Results: i) The amount of propofole varied significantly between the two groups (50-80 μg/kg/min less in group B). ii) Recovery time was significantly less (2-10 mins) in group B than in group A (6-33 mins). iii) Regarding to postoperative sedation and cognitive function group B’s scores were significantly higher (8-10) especially in the first 15 minutes after extubation than the ones of group A (5-10).

  Conclusion: These results suggest that BIS’s use in the head and neck surgical procedures proves to be advantageous because it reduces the need for anaesthetic agent (propofole) and saves time on the operating table due to the fast recovery of the patient.