Abstract
Background: Haemodynamic stability and rapid emergence after general anaesthesia used in spinal
surgery is a common practice, the goal of which is to permit early neurological motor
and sensory examination. Extubation is almost always associated with hypertension,
increased airway response and arrhythmias. We have compared the effects of the α-2
agonist Dexmedetomidine and Lignocaine given at the end of the procedure on attenuation
of airway and pressor responses following tracheal extubation. This study is a randomised,
placebo-controlled, double-blinded study. Materials and Methods: Sixty ASA I-III patients, aged 18-70 years, scheduled to undergo spinal surgery at
the level of thoracic, lumbar or sacral region were randomly divided into three groups.
Balanced general anaesthesia comprising standard procedures and drugs were used for
monitoring, induction and maintenance. At the last skin suture, inhalation anaesthetic
was discontinued. After turning the patient supine and return of spontaneous efforts,
in Group D Dexmedetomidine 0.5 μg/kg, in Group L Lignocaine 1.5 mg/kg and in Group
P normal saline (10 ml) were administered as bolus intravenously over 60 seconds.
Systolic, diastolic and mean arterial pressures and heart rate were recorded before
intravenous administration and also every minute for 3 minutes, at 5, 10 and 15 minutes
post-extubation. Duration of emergence and extubation were noted and attenuation of
airway response and quality of extubation was evaluated on cough grading. Results: Mean arterial pressures and heart rate were higher in Group L and Group P than in
Group D but not statistically significant. The duration of emergence, extubation and
recovery were comparable in all the groups (P > 0.05). Extubation Quality Scores was 1 in 80%, 2 in 20% in Group D; in Group L,
the quality scores were 1 for 55%, 2 for 45% and I Group P 1 for 35%, 2 for 45% and
3 for 20% of the patients. The requirement of rescue analgesia was also less and after
prolonged time in Group D than in Group L and Group P (P < 0.05). None of the patients in all three groups showed respiratory depression,
allergic reactions, nausea, vomiting or shivering. There was occurrence of hypertension
for the initial 3 minutes of administration of drug in 10 (50%) of patients in Group
D (Dexmedetomidine) group. Conclusion: Without interfering in emergence and extubation times, attenuation of pressor response
is comparable between Dexmedetomidine 0.5 μg/kg and Lignocaine 1.5 mg/kg but airway
response is much better controlled allowing a smooth easy extubation providing a more
comfortable recovery and early neurological examination following spinal surgeries.
Keywords
Airway responses - dexmedetomidine - haemodynamics - lignocaine - tracheal extubation
