Is elevated blood glucose a marker of occult tissue hypoperfusion in off-pump coronary artery bypass grafting?

Context: Hyperglycemia has been found to occur during myocardial infarction and cardiac surgery even in nondiabetic patients. These being essentially stressful processes associated with hypoperfusion, we decided to find a possible relationship between the occurrence of global tissue hypoperfusion (GTH) and elevated blood glucose level in adult nondiabetic patients undergoing elective off-pump coronary artery bypass grafting (CABG). Aims: This study aims to observe for the occurrence of global tissue hypoperfusion and its effect on blood glucose level and whether raised blood glucose level can be used as a marker for GTH. Design: Prospective, observational study. Settings: Cardiothoracic operation theater and intensive care unit of a tertiary care teaching hospital. Materials and Methods: The occurrence of global tissue hypoperfusion were detected with the help of combined markers of mixed venous oxygen saturation and arterial lactate level at various perioperative study points together with arterial blood glucose level. Blood glucose level compared between the patients with and without GTH. Statistical Analysis Used: Numerical variables were compared between groups by Student's t-test and categorical variables by Fisher's exact test. Two-tailed P ≤ 0.05 was considered for statistically significant. Results: The incidence of GTH was 67%. Blood glucose level was raised in patients with GTH at some study time points but with poor sensitivity and specificity values. Conclusions: Global tissue hypoperfusion is a common occurrence in even nondiabetic patients undergoing elective off-pump CABG. A relationship exists between rise in blood glucose level and global tissue hypoperfusion in such patients, although it cannot be viewed as marker of the same.

Effect of Vitamin C on adrenal suppression by etomidate induction in patients undergoing cardiac surgery: A randomized controlled trial.

Introduction: Etomidate is usually preferred in the induction of cardiac compromised patients due to its relative cardiovascular stability. However, the use of this drug has been limited as etomidate induces suppression of cortisol biosynthesis as a result of blockade of 11‑beta‑hydroxylation in the adrenal gland, mediated by the imidazole radical of etomidate. This study was carried out to observe the effect of Vitamin C on adrenal suppression after etomidate induction in patients undergoing cardiac surgery. Materials and Methods: A total of 78 patients were randomly distributed into two groups. Group‑I received oral Vitamin C (500 mg) twice daily and Group‑II received antacid tablet as placebo twice daily instead of Vitamin C for 7 consecutive days prior to surgery till morning of surgery. Patients of both the groups induced with etomidate (0.1–0.3 mg/kg). Blood cortisol was estimated at different points of time till 24th postinduction hour/blood lactate, glucose, hemodynamic parameters, and perioperative outcomes were assessed. Results: Data of seventy patients (n = 35 in each group) were finally analyzed. Cortisol level is statistically significantly higher in Group‑I (69.51 ± 7.65) as compared to Group‑II (27.74 ± 4.72) (P < 0.05) in the 1st postinduction hour. In Group‑II, cortisol was consistently lower for 1st 24 postinduction hour. Total adrenaline requirement was statistically significantly high in Group‑II. Time of extubation, length of Intensive Care Unit stay arrhythmia was similar in both the groups. Conclusion: Vitamin C effectively inhibits etomidate‑induced adrenal suppression in cardiac patients, thereby etomidate can be used as a safe alternative for induction in cardiac surgery under cardiopulmonary bypass when pretreated with Vitamin C.

Effect of prophylactic amiodarone in patients with rheumatic valve disease undergoing valve replacement surgery.

The study was carried out to evaluate the effect of prophylactic single-dose intravenous amiodarone in patients undergoing valve replacement surgery. Maintenance of sinus rhythm is better than maintenance of fixed ventricular rate in atrial fibrillation (AF) especially in the presence of irritable left or right atrium because of enlargement. Fifty-six patients with valvular heart disease with or without AF were randomly divided into two groups. Group I or the amiodarone group (n=28) received amiodarone (3 mg/kg in 100 ml normal saline) and group II or the control group received same volume of normal saline. The standardized protocol for cardiopulmonary bypass was maintained for all the patients. AF occurred in 7.14% patients in group I, and in group II, 28.57% (P=0.035); ventricular tachycardia/fibrillation was observed in 21.43% patients in group I and 46.43% patients in group II (P=0.089) after release of aortic clamp. Most of the patients in group I (92.86%) maintained sinus rhythm without cardioversion or defibrillation after release of aortic cross clamp (P=0.002). Defibrillation or cardio version was needed in 7.14% patients in group I and 28.57% patients in group II (P=0.078). A single prophylactic intraoperative dose of intravenous amiodarone decreased post bypass arrhythmia in this study in comparison to the control group. Single dose of intraoperative amiodarone may be used to decrease postoperative arrhythmia in open heart surgery.

Controlled transient respiratory arrest along with rapid right ventricular pacing for improving balloon stability during balloon valvuloplasty in pediatric patients with congenital aortic stenosis - A retrospective case series analysis.

Rapid right ventricular pacing is safe, effective, and established method to provide balloon stability during balloon aortic valvuloplasty (BAV). Controlled transient respiratory arrest at this point of time may further reduce left ventricular stroke volume, providing an additional benefit to maintain balloon stability. Two groups were studied. Among the 10 patients, five had rapid pacing alone (Group A), while the other five were provided with cessation of positive pressure breathing as well (Group B). The outcomes of BAV in the two groups of patients were studied. One patient in Group A had failed balloon dilatation even after the fourth attempt, while in Group B there were no failures. The peak systolic gradient reduction was higher in Group B (70.05% in comparison to 52.16% of group A). In Group A, five subjects developed aortic regurgitation (grade 2 in four and grade 3 in one, while no grade 3 aortic regurgitation developed in any patient in Group B). Controlled transient respiratory arrest along with rapid ventricular pacing may be effective in maintaining balloon stability and improve the outcome of BAV.

Perioperative management of pregnant patients with heart disease for caesarian section under anaesthesia.

One hundred pregnant patients, of age group 22 to 35 years, with different types of cardiac ailments (mitral stenosis, mitral regurgitation, mitral valve prolapse, aortic regurgitation, atrial septal defect, ventricular septal defect, coarctation of the aorta, Eisenmenger syndrome, hypertrophic obstructive cardiomyopathy and operated tetralogy of fallot), put up for elective caesarian section underanaesthesia, were managed in the department of anaesthesiology at IPGME&R/SSKM Hospital, Kolkata from January 1996 to December 2002. The aim of the study was to observe the maternal and foetal outcome in different heart diseases. Death occurred in 2 patients (67%) with Eisenmenger syndrome, in one patient (20%) with hypertrophic obstructive cardiomyopathy and in one patient (5%) with critical mitral stenosis (mitral orifice area = 0.6 cm2) with pulmonary arterial hypertension (PAH). Neonatal mortality was observed in 4 patients [Eisenmenger syndrome--3 (100%); coarctation of the aorta--1 (33%)]. Another 8 patients developed severe heart failure (HF) [severe mitral stenosis (mitral orifice area = 1-1.2 cm2)--2 (10%); hypertrophic obstructive cardiomyopathy--4 (80%); coarctation of the aorta--2 (66%)]. Foetal dysmaturity was observed in 20 neonates (54%) belonging to mothers of New York Heart Association (NYHA) classes III and IV. Congenital heart disease (ventricular septal defect) was detected in 3 offsprings (20%) of mothers with ventricular septal defect. The study concludes that most pregnant cardiac patients can have a satisfactory outcome with careful perioperative management.