Evaluation of inferior alveolar nerve block as an adjunct to general anaesthesia for mandibulectomy

Abstract

Aims & Objectives

Introduction of regional anaesthetictechniques into modern anesthesia has revolutionized pain management. The most popular anestheticprocedure used  for mandibularanesthesia,

is the inferioralveolar nerve block (IANB). This prospective pilot trial is being undertaken

 To study the efficacyof inferior alveolar nerve block for intraoperative analgesia in terms of

1.  Consumption of opioids in intraoperative period

2.  Hemodynamic stability in intraoperative period

In comparison withgeneral anesthesia alone.

 Methodology

Study setting:

This study will beconducted in the department of Anaesthesiology of Regional cancer centre,Thiruvananthapuram.

 Study Design- Prospective randomized controlled trial

 After a detailed pre anaestheticcheck up (PAC) according to institutional protocols, patients will be randomlydivided using computer generated random number tables into group A (generalanaesthesia only) and group B (general anaesthesia with inferior alveolar nerveblock).

 Parameters noted after the block

Sensory loss will bedetected in terms of loss to cold sensation and the time of onset on sensoryloss will also be noted

in the followingareas

 1.  Numbness in the lower lip/chin

2.  Numbness in tongue

3.  Incidence of positive aspiration test

Vital charting ( Bloodpressure, Heart rate) will be particularly noted at crucial events like tonguestitch, dental extraction, osteotomy, condylotomy, marginal resection alongwith the usual vital charting at 15 minutes interval.The vital signs and painscoring will be noted by an independent observor who will be blinded to whetherthe block has been performed in the patient or not.

 The primary objective ofthe study will be to estimate opioid consumption to maintain hemodynamic stability in both the groups. Anyraise in blood pressure or heart rate more than 20% of baseline will be managedwith a bolus of fentanyl 1 mcg/kg. This dose will be repeated after 5 minutesif there is no adequate response and the number of doses and the amount ofdoses required will be noted.

 Statistical Analysis

Sample size:

The pilot study with 10 samples in each group will be undertaken forpatients fulfilling the eligibility criterion and consenting to the study.

 Statistical Methods:

The categorical variables will be summarized using frequency orpercentage and continuous variables using mean and standard deviation. Thecomparison between the groups will be done using students t-test for normallydistributed continuous variables and Mann-whitney U test for non-normalvariables. For comparing two categorical variables, chi-square or Fishers exacttest will be used.