Intravenous dexmedetomidine vs. lignocaine in attenuating the hemodynamic responses during laryngoscopy and endotracheal intubation: a randomized double blind study

Background: The stress response to laryngoscopy and endotracheal intubation is a commonly encountered physiological phenomenon. Though the response can be transient and harmless in normotensive healthy patients, but it may prove hazardous amongst patient with underlying cardiac disease, or hypertensive disease and its sequelae. Present study was planned to evaluate the efficacy of IV dexmedetomidine infusion and IV lignocaine in attenuating the hemodynamic responses during laryngoscopy and intubation

Methodology: On approval from hospital ethical committee, 120 ASA grade I and II, normotensive patients in the age group of 18-60 years, planned for elective surgery under general anesthesia were enrolled in the study. Patients were divided into 3 equal groups of 40 each; Group A [Lignocaine group] received lignocaine 1.5 mg/kg IV 2 min before induction, Group B [dexmedetomidine group ] received dexmedetomidine 1 micro /kg IV infusion with syringe pump 10 min before induction, and Group C [control group] received normal saline before induction. Heart rate [HR], systolic blood pressure [SBP], diastolic blood pressure [DBP], mean arterial pressure [MAP], oxygen saturation of arterial blood [SpO2] and electrocardiogram [ECG] were monitored at induction, intubation and post intubation at one minute interval till 10th minute

Results: A better control of stress response was observed in patients receiving dexmedetomidine infusion. More decrease in HR was noted in Group B as compared to Group A [9.28 % vs. 13.40%] respectively. The decrease in MAP was also more in Group B as compared to group receiving lignocaine [5.49 % vs. 10.72%] respectively

Conclusion: Dexmedetomidine 1 micro g/kg IV is more effective in blunting stress response to laryngoscopy and endotracheal intubation as compared to lignocaine 1.5 mg/kg IV

Is dexmedetomidine a better sedative agent than clonidine in spinal anesthesia?

Background and Aims: Regional anesthesia offers benefits to patients and anesthetists by keeping the patients awake, preserving the airway reflexes, by providing cardiovascular stability during the procedure and fast postoperative recovery. Patients are often uncomfortable, because of pain at puncture site, recall of procedure and limited duration of blockade. Alpha-2 adrenoreceptor agonists were introduced in anesthesia for their sedative and analgesic effects. The aim of this study was to compare the effects of intravenous dexmedetomidine or clonidine as adjuvants during bupivacaine spinal anesthesia

Methodology: A prospective, randomized study was conducted involving 120 patients scheduled for elective infraumbilical surgery under spinal anesthesia. Patients were randomly divided into three groups [n = 40] and were given the following drugs intravenously as per group allocation: Group A received 1 microg/kg of dexmedetomidine, followed by an infusion at the rate of 0.5 microg/kg/h; Group B received 1 microg/ kg of clonidine, followed by an infusion at rate of 1 microg/kg/h and Group C received normal saline bolus and infusion. Loading dose was given over 10 min, prior to [SAB], followed by a maintenance infusion. Ramsay sedation score of 3-4 was considered as target sedation. Patients were assessed for time required to achieve target sedation, prolongation of analgesia and motor blockade. The hemodynamic parameters and side effects were also observed

Results: The target sedation was achieved significantly earlier in Group A [14.32 +/- 5.25 min] as compared to Group B [30.01 +/- 2.33 min] [P = 0.001]. In Group A, the mean duration of analgesia was 208.25 +/- 28.29 min as compared to 169.75 +/- 20.15 min in Group B and 135.25 +/- 22.60 min in Group C [P < 0.05]. Duration of motor blockade was increased in Group A [217 +/- 24.697 min] as compared to Group B and C

Conclusion: Intravenous dexmedetomidine infusion is better than intravenous clonidine as it provides earlier onset of adequate sedation along with prolongation of analgesia and motor blockade during bupivacaine spinal anesthesia