Abstract :
Background and Objective: Laryngoscopy and endotracheal intubation employed for general
anaesthesia cause noxious stimuli and are associated with laryngo- sympathetic stimulation manifested
by hypertension, tachycardia and arrhythmias. This study compares the efficacy of dexmedetomidine and
fentanyl in attenuating haemodynamic stress responses to laryngoscopic endo-tracheal intubation in adult
patients undergoing surgeries under general anaesthesia.
Materials and Methods: 90 adult participants of any sex aged between 18-55yrs undergoing elective
surgeries under general endo-tracheal anaesthesia were divided into 3 groups of 30 patients in each group.
Group C: Control group – received 10ml of normal saline (NS) intravenously (IV) over 10 minutes (min),
10min before induction. Group D: Dexmedetomidine group - received IV Dexmedetomidine 0.6mg/kg
body weight diluted to 1 0ml of NS IV over 10min using a syringe pump and 3ml of NS IV 2min before
induction. Group F: Fentanyl group - received 10ml of NS IV over 10min using a syringe pump and IV
Fentanyl 2mg/kg body weight diluted to 3ml of NS IV 2min before induction. Anaesthesia was induced
with IV Thiopentone sodium 5 mg/kg body weight and IV Vecuronium 0.1mg/kg body weight to facilitate
endotracheal intubation. Lignocaine 1.5mg/kg IV was given 90seconds before intubation in all the groups.
Anaesthesia was maintained with Oxygen, Nitrous Oxide, 1-2% Sevoflourane and IV Vecuronium. Heart
rate (HR), systolic blood pressure (SBP), diastolic blood pressure (DBP) and mean arterial pressure (MAP)
were recorded at various time intervals.
Results: In group C, 1min after laryngoscopy and intubation, the rise in HR, SBP, DBP and MAP were
42bpm, 30mmHg, 22 mmHg and 24mmHg respectively compared to basal values. In group F, 1min after
laryngoscopy and intubation, the rise in HR was 14bpm, rise in SBP, DBP and MAP each by 2mmHg
compared to basal values. In group D, HR, SBP, DBP and MAP were decreased by 4bpm, 23 mmHg,
25mmHg and 24 mmHg respectively compared to basal values at 1min after laryngoscopy and intubation
which was statistically highly significant (p=0.000).
Interpretation and Conclusion: Both IV Dexmedetomedine 0.6mg/kg body weight administered over
10min and IV Fentanyl 2mg/kg body weight administered over 2min prior to induction are effective
in obtunding the haemodynamic stress response to laryngoscopy and intubation without any significant
side effects. However IV Dexmedetomidine is more effective and superior than Fentanyl in attenuating
haemodynamic response to laryngoscopy and endotracheal intubation.
Keyword :
Dexmedetomidine fentanyl laryngoscopy and endotracheal intubation attenuation hemodynamic responses.