Incidence and implications of coronary artery disease in patients undergoing valvular heart surgery: The Indian scenario.

Aims and Objectives: We evaluated the incidence and implications of coronary artery disease (CAD) in patients above 40 years presenting for valve surgery. Materials and Methods: Between January 2009 and December 2010, coronary angiography (CAG) was performed in all such patients ( n = 140). Results: Coronaries were normal in 119 (Group I), and diseased in 21 (Group II). In Group II, 11 patients were < 50 years, 3 were between 51 and 60 years and 7 were > 61 years. In 8 of these, only valve replacement was performed. Coronary artery bypass grafting (CABG) and aortic valve replacement was performed in 10, CABG and mitral valve replacement in 2 and CABG with mitral and aortic valve replacement in one. The number of vessels grafted in these 13 patients was 1.54 ± 0.66. Hypertension and diabetes were significant ( P < 0.05) in this group. The mortality was significant in Group II (11 vs. 6, P < 0.05). Six patients died in Group II, 5 had severe aortic stenosis and severe left ventricular hypertrophy; the sixth patient had severe mitral stenosis and was in CHF. The predominant cause of death was congestive heart failure (CHF). Conclusions: Fifteen percentage of these patients had CAD. CAG should be performed routinely in these patients while presenting for valve surgery. Combined CABG and valve replacement carries high mortality (28.5%), especially in patients with aortic stenosis. The study suggests that the cardio-protective measures should be applied more rigorously in this subset of patients.

The success rate and safety of internal jugular vein cannulation using anatomical landmark technique in patients undergoing cardiothoracic surgery.

Aims and objectives: Landmark-guided internal jugular vein (IJV) cannulation is a basic procedure, which every anesthetist is expected to acquire. A successful first attempt is desirable as each attempt increases the risk of complications. The present study is an analysis of 976 IJV cannulations performed in adults undergoing cardiothoracic surgery. Materials and Methods: The IJV was cannulated with a triple lumen catheter using the anatomical landmarks. The following data were recorded: Patient demographics, age, sex, body mass index, diagnosis, operative procedure, operator (resident/consultant), site of cannulation (central approach, right IJV, left IJV, external jugular vein), number of attempts and duration of cannulation, length of insertion of the catheter, number of correct placements on X-ray and any complications. Results: The success rate of IJV cannulation was 100%. In 809 (82.9%) patients, cannulation was performed in the first attempt. Residents performed 792 cannulations and the consultants performed 184 cannulations. In 767 patients, the residents were successful in inserting the catheter and in 25 they failed after 5 attempts, hence, they were cannulated by the consultant. The time taken for insertion of the catheter was 6.89 ± 3.2 minutes. Carotid artery puncture was the most common complication, it occurred in 22 (2.3%) patients. Conclusion: IJV cannulation with landmark technique is highly successful with minimal complications in the adult patients undergoing cardiothoracic surgery. Basic training of cannulating the IJV by landmark technique should be imparted to all the traines as ultrasound may not be available in all locations.

Effect of muscle relaxants on heart rate, arterial pressure, intubation conditions and onset of neuromuscular block in patients undergoing valve surgery.

Sixty six patients undergoing elective valve surgery were randomized to receive rocuronium bromide 0.6 mg/Kg (Group R, n=22), pancuronium bromide 0.1 mg/Kg (Group P, n= 22) and vecuronium bromide 0.1 mg/Kg (Group V, n=22), Measurements of heart rate and arterial pressure (systolic, diastolic and mean) were noted at the following stages: 1) baseline when haemodynamics were stable for 2 minutes after induction of anaesthesia (2) one, (3) three, (4) five minutes after administration of muscle relaxants, (5) One, (6) three, and (7) five minutes after intubation. In group R, the heart rate decreased 5 min after injection of muscle relaxant from 93.9 +/- 21.3 to 82.4 +/- 20.7 beats/min (p<0.001). However, it increased to 128.3 +/- 25.8 beats/min (p<0.001) following intubation and returned to baseline at 5 min after intubation. In group P, heart rate increased from 98.8 +/- 32.6 to 109.6 +/- 32.7 beats/min (p<0.001), 1 min after injection of pancuronium and this increase persisted throughout the study period. In group V, heart rate decreased from 99.9 +/- 22.3 to 83.8 +/-19.6 beats/min (p<0.001) at 5 min after injection of the drug. It increased to 118.6 +/- 22.4 beats/min (p<0.001), 1 min after intubation and returned to baseline at 5 min after intubation. The decrease in heart rate in group R and V was accompanied by a significant decrease in systolic, diastolic and mean arterial pressure. In group P, only the systolic pressure decreased significantly at 5 min after injection of the drug. Intubation was accompanied by a significant increased in systolic, diastolic and mean arterial pressure in all the groups. Excellent intubation conditions (intubation score 3-4) were observed with all the three drugs, however, there were number of patients in group P who showed diaphragmatic movement during intubation. Onset of action of muscle relaxant, was fastest with rocuronium (group R=132.7 +/- 0.3 sec, P=182.6 +/- 68.5 sec, V= 144.8 +/- 46.1 sec, Group P vs Group R). To conclude, pancuronium causes significant increase in heart rate and should be preferred in patients with regurgitant lesions having slower baseline heart rate. Vecuronium and rocuronium decrease the heart rate and should be preferred in patient with faster baseline heart rate. In terms of intubating conditions rocuronium and vecuronium provide best conditions, but onset is faster with rocuronium.

Atrial ECG as a guide to the placement of central venous catheter in patients undergoing Open Heart Surgery.

Hundred adults undergoing open heart surgery were randomized into two equal groups. In group I (n=50), surface anatomical landmarks and in group II (n=50) atrial ECG was used as a guide for correct placement of the central venous catheter (within 1 cm of superior vena cava - right atrial junction). The position of the catheter tip was confirmed by direct palpation by the surgeon on the operating table and by radiological examination in the post operative period. Surgeon's assessment revealed that the catheter was successfully placed in 32 (69.6%) patients in group II and 25 (50%) patients in group I (p=NS). Radiological examination revealed that the catheter was successfully placed in 31 (67.4%) patients in group II and in 28 (57.1%) patients in group I (p=NS). Amongst the unsuccessful placements right atrial placement was present in 5 patients (10%) in group I and 7 patients (15.2%) in group II by surgeon's assessment and 8 patients (16.3%) in group I and 9 patients (9.6%) in group II by radiological examination (p=NS) No complications related to intracardiac placement occurred in any of the patients. We conclude that atrial ECG is a promising technique for central venous catheter placement, although it did not significantly increase the correct placement in this study. This may be due to alteration in the relationship of sino-atrial node and superior vena cava - right atrial junction in patients with cardiac disease. Further studies defining the correct technique of insertion, (especially in cardiac patients) are necessary to improve the success rate.