The effects of dexmedetomidine on attenuation of stress response to endotracheal intubation in patients undergoing elective off-pump coronary artery bypass grafting.

This study was designed to study the efficacy of intravenous dexmedetomidine for attenuation of cardiovascular responses to laryngoscopy and endotracheal intubation in patients with coronary artery disease. Sixty adult patients scheduled for elective off-pump coronary artery bypass surgery were randomly allocated to receive dexmedetomidine (0.5 mcg/kg) or normal saline 15 min before intubation. Patients were compared for hemodynamic changes (heart rate, arterial blood pressure and pulmonary artery pressure) at baseline, 5 min after drug infusion, before intubation and 1, 3 and 5 min after intubation. The dexmedetomidine group had a better control of hemodynamics during laryngoscopy and endotracheal intubation. Dexmedetomidine at a dose of 0.5 mcg/kg as 10-min infusion was administered prior to induction of general anesthesia attenuates the sympathetic response to laryngoscopy and intubation in patients undergoing myocardial revascularization. The authors suggest its administration even in patients receiving beta blockers.

The effects of preemptive pregabalin on attenuation of stress response to endotracheal intubation and opioid- sparing effect in patients undergoing off-pump coronary artery bypass grafting.

The clinical study was designed to evaluate and compare single preoperative dose of pregabalin to a placebo regarding hemodynamic responses to laryngoscopy and endotracheal intubation, to assess perioperative fentanyl requirement and any side-effects. It was a randomized, double-blind, placebo-controlled, parallel assignment, efficacy study. The study was done at a tertiary university hospital. This study was a comparison between two groups of 30 adult patients scheduled for elective off pump coronary artery bypass surgery. In the control group, the patients were given placebo capsules, and in the pregabalin group, the patients were given pregabalin 150 mg capsule orally 1 h before surgery. The patients were compared for hemodynamic changes before the start of the surgery, after induction, 1, 3, and 5 min after intubation. Additionally, fentanyl requirement during surgery and the first postoperative day was also compared. The present study shows that a single oral dose of 150 mg pregabalin given 1 h before surgery attenuated the pressor response to tracheal intubation in adults, but the drug did not show any effect on perioperative opioid consumption and was devoid of side-effects in the given dose.

Intraoperative anastomotic site detection and assessment of LIMA-to-LAD anastomosis by epicardial ultrasound in off-pump coronary artery bypass grafting - A prospective single-blinded study.

The study was done to detect the optimal site of left anterior descending (LAD) artery for grafting and for the assessment of geometrical and anatomical characteristics of left internal mammary artery (LIMA)-to-LAD artery anastomosis in elective off-pump coronary artery bypass grafting surgery. Fifteen consecutive patients who underwent coronary artery bypass graft (CABG) were included in the study. All the operations were performed by a single surgeon. Epicardial ultrasound probe was placed at the site of grafting for scanning and the site of anastomosis selected. The anticipated target site selected by the surgeon was scanned for patency, size, septal perforator branches, and presence of plaque and calcification. The surgeon identified the LAD artery in 12 patients. In three patients, the LAD artery was not visible. However, with epicardial ultrasound, the LAD artery was identified in all patients. In 6 of 15 patients, the anticipated target anastomotic site was changed to a clear segment either due to the presence of perforators or plaques or calcifications. In all 15 patients, the surgeon scored the anastomosis as good, based on his or her experience independent of the ultrasound image. The anastomotic score by the cardiac anesthesiologist showed 5 anastomoses with satisfactory results and 10 anastomoses with good results. The study demonstrates that epicardial ultrasound scanning with a 10-MHz transducer provides reliable information in choosing the proper anastomotic site and allows proper visualization of LIMA-to-LAD anastomosis. All these measurements are easily obtained without risk of any complications and the method is not time consuming.