Mesenteric ischaemia ocurring as a late complication after-aorto-femoral bypass.

Patients with coexisting peripheral vascular disease and coronary artery disease constitute a high risk surgical group. Perioperative management of such patients is an anaesthetic challenge. A 57-year-old male presented with critical limb ischaemia and impending gangrene of the right lower limb. Associated coronary artery disease with triple vessel involvement was diagnosed on coronary angiography. This patient underwent an aorto-femoral bypass. The postoperative course was complicated by the development of mesenteric ischaemia requiring emergency laparotomy and bowel resection.

A randomized trial of anesthetic induction agents in patients with coronary artery disease and left ventricular dysfunction.

The deleterious effects of anesthetic agents in patients suffering from coronary artery disease are well known. The risk increases when a patient has compromised ventricular function. There is a paucity of literature regarding the choice of the suitable agent to avoid deleterious effects in such patients. The use of etomidate and propofol has been considered superior to other intravenous anesthetic agents in these groups of patients. The aim of the present study is to compare the hemodynamic effects of anesthesia induction with etomidate, thiopentone, propofol, and midazolam in patients with coronary artery disease and left ventricular dysfunction. This randomized clinical trail was conducted at the All Indian Institute of Medical Sciences, New Delhi, India. Sixty patients with coronary artery disease and left ventricular dysfunction (ejection fraction < 45%) scheduled for elective coronary artery bypass surgery participated in this study. After stabilization baseline hemodynamic data stroke volume variation and systemic vascular resistance index were recorded for all patients (Flo Trac TM sensor with Vigileo cardiac output monitor used for hemodynamic monitoring). The patients were randomly alloted to one of the four groups and the intravenous induction agent was administered for over 60-90 seconds (Group E--Etomidate 0.2 mg/Kg; Group M--Midazolam 0.15 mg/Kg; Group T--Thiopentone 5 mg/Kg; Group P--Propofol 1.5 mg/Kg). Hemodynamic data were recorded at one minute intervals starting from induction till seven minutes after intubation,--the end point of the present study. There was a significant decrease in the heart rate in comparison to the baseline(-7 to -15%, P = 0.001), mean arterial pressure (-27 to -32%, P = 0.001), cardiac index (-36 to -38%, P = 0.001), and stroke volume index (-27 to -34%, P = 0.001) after induction in all four groups. The hemodynamic response was similar in all the four groups. There was no significant change in central venous pressure and stroke volume variation (SVV) during induction and intubation, while the effects on the systemic vascular resistance index (SVRI) were variable. The midazolam group was the most effective in preventing intubation stress (tachycardia,hypertension). The change from baseline values in heart rate (+ 4%, P = 0.12) and mean arterial pressure (-1%, P = 0.77) after intubation were not statistically significant in the midazolam group. The etomidate group was the least effective of all the four groups in minimizing stress response, with statistically significant increase from baseline in both heart rate (P = 0.001) and mean arterial pressure (P = 0.001) at 1 minute after intubation. All the four anesthetic agents were acceptable for induction in patients with coronary artery disease and left ventricular dysfunction despite a 30-40% decrease in the cardiac index. Clinician experience along with knowledge of the potential interactions (e.g., premedication, concurrent opioid use) is needed to determine hemodynamic stability during anesthetic induction in these patients with ventricular dysfunction.

Cognitive dysfunction after cardiac surgery.

Both short and long term cognitive changes occur after cardiac surgery but the pathophysiology of these neurobehavioral changes remain incompletely understood. The cause of cognitive decline is most likely multifactorial and probably represents a complex interaction between cerebral microemboli, global cerebral hypoperfusion, inflammation, and genetic susceptibility. The problem of cognitive decline after cardiac surgery continues to increase as the surgical population becomes older and has more prevalent comorbid diseases. A better understanding of the etiology is essential to finding new preventive strategies as no definitive therapy exists for cognitive dysfunction.

Inhaled nitroglycerin versus inhaled milrinone in children with congenital heart disease suffering from pulmonary artery hypertension.

OBJECTIVE: The aim of the present study was to compare the acute effects of inhaled milrinone and inhaled nitroglycerin on pulmonary and systemic hemodynamics in children with acyanotic congenital heart disease (left-to-right shunt) and pulmonary artery hypertension. DESIGN: Randomized clinical trial. SETTING: Catheterization laboratory of a tertiary care hospital. PARTICIPANTS: Thirty-five children below the age of 12 years who were suffering from acyanotic congenital heart disease with left-to-right intracardiac shunt and pulmonary artery hypertension (mean PA pressure > 30 mmHg). INTERVENTION: Right-heart catheterization was done using an end-hole balloon wedge pressure catheter. Baseline pulmonary and systemic hemodynamic parameters were recorded for all patients while breathing room air. All patients then underwent pulmonary vasodilator testing with 100% oxygen. Following this, patients were randomized into two groups and received either inhaled milrinone (group M, n = 18) or inhaled nitroglycerin (group N, n = 17) in a 50% air-oxygen mixture. Oximetry data were used to calculate systemic and pulmonary cardiac output based on Fick's principle. RESULTS: Systolic, diastolic, and mean pulmonary artery pressures decreased significantly in both the groups after drug nebulization, while there were no significant changes in systemic pressures. The percentage decrease from baseline in systolic (5.2% v 8.6%, p = 0.43), diastolic (19.5% v 16.8%, p = 0.19) and mean (14.9% v14.5%, p = 0.29) pulmonary artery pressures were comparable in both groups. The pulmonary vascular resistance index (PVRI) decreased from 9.0 ± 3.9 to 2.9 ± 1.7 Wood Units (WU)/m(2) in group M (p < 0.001) and from 8.6 ± 3.8 to 3.2 ± 3.3 WU/m(2) in group N (p < 0.001). The fall in pulmonary artery pressures after drug nebulization in both groups was comparable to the fall seen with 100% oxygen. CONCLUSION: Both milrinone and nitroglycerin when given via the inhaled route significantly decrease systolic, diastolic and mean pulmonary artery pressures as well as PVRI without significant effects on systemic hemodynamics. Both the drugs given via inhaled route therefore can offer a good therapeutic choice and can help decrease the high inspired oxygen concentrations needed to treat pulmonary artery hypertensive episodes in perioperative settings.

Role of Bupivacaine in reducing post tonsillectomy pain.

Pain following tonsilleclomy is of major concern to both the surgeons and the Anesthesiologists. Pre-incisional Bupivacaine infiltration into the tonsillar fossa has been used as a method of relieving post-operative pain in children. In this study pre-incisional Bupivacaine infiltration into the tonsillar fossa resulted in immediate post-operative pain lasting four to six hours.