Effect of Perioperative Use of Oral Triidothyronine for Infants Undergoing Complex Congenital Cardiac Surgeries Under Cardiopulmonary Bypass: A Double?Blinded Randomised Controlled Study

Background: Thyroid hormone metabolism disrupts after cardiopulmonary bypass both in adults and pediatric patients. This is known as Euthyroid sick syndrome, and it is more evident in pediatric patients who were undergoing complex cardiac surgeries compared to adults. This decrease in serum T3 levels increases the incidence of low cardiac output, requirement of inotropes, prolonged mechanical ventilation, and prolonged intensive care unit (ICU) stay. Aims and Objectives: The primary objective was to compare the mean Vasoactive?inotropic score (VIS) at 72 hours postoperatively between T3 and Placebo groups. Materials and Methods: One hundred patients were screened, and 88 patients were included in the study. Triidothyronine 1 mic/kg 10 doses 8th hourly was given orally postoperatively to cases and sugar sachets to controls. The blood samples for analysis of FT3, FT4, and TSH were taken every 24 hours postoperatively, and baseline values were taken after induction. Mean VIS scores, ejection Fraction (EF), Left ventricular outflow tract velocity time integral (LVOT VTi), hemodynamics and partial pressure of oxygen/ fraction of inspired oxygen(PaO2/ FiO2) were recorded daily. Results: The Mean VIS scores at 72 Hours postoperatively were significantly less in the T3 group (5.49 ± 6.2) compared to the Placebo group (13.6 ± 11.7).The PaO2/FiO2 ratios were comparatively more in the T3 group than the Placebo group.The serum levels of FT3 FT4 were significantly higher in the T3?supplemented group than the Placebo group.TheVIS scores were significantly lower from48 hours postoperatively in children < 6 months of age. Conclusion: In this study, we observed that supplementing T3 postoperatively decreases the ionotropic requirement from 72 hours postoperatively. This is more useful in children <6 months of age undergoing complex cardiac surgeries.

Dexmedetomidine versus ketofol sedation for outpatient diagnostic transesophageal echocardiography: A randomized controlled study

Background: Moderate sedation is required for out-patient transesophageal echocardiography (TEE). Our objective was to compare the effect of Ketofol and dexmedetomidine for outpatient procedural sedation in diagnostic TEE with a hypothesis that Ketofol would be as effective as dexmedetomidine. Patients and Methods: Fifty adult patients of age group 18-60 years with atrial septal defect, rheumatic valvular heart disease undergoing diagnostic TEE in the outpatient echocardiography laboratory were randomized into two groups, group D and group KF. GROUP D: Dexmedetomidine infusion -200 μg in 20 ml normal saline. GROUP KF: Ketofol infusion: (ketamine: propofol, 1mg: 3 mg in 20 ml syringe). Loading dose of drug at 1ml/kg/hour IV till Ramsay sedation score (RSS) ≥ 3 achieved followed by maintenance infusion at 0.05 ml/kg/hour till end of procedure. Results: The primary outcome - time to achieve Ramsay sedation score ≥ 3 was significantly lesser with Ketofol as compared to Dexmedetomidine 260[69] seconds vs 460 [137], (p value<0.05).Conclusion: In out-patient setting, ketofol is favourable over dexmedetomidine for sedation regimen for diagnostic TEE as lesser time is taken to achieve optimal sedation with lesser hemodynamic perturbations, post procedure complications and better cardiologist satisfaction.

Acute hemodynamic effects of inhaled nitroglycerine, intravenous nitroglycerine, and their combination with intravenous dobutamine in patients with secondary pulmonary hypertension.

Objectives: The presence of pulmonary artery hypertension (PAH) affects the prognosis of patients; therefore, it is important to treat it. The aim of this study is to compare the acute hemodynamic effects of inhaled nitroglycerine (iNTG), intravenous nitroglycerine (IV NTG) alone and their combination with intravenous dobutamine (IV DOB) during the early postoperative period, in patients with PAH undergoing mitral valve or double valve replacement surgery. Materials and Methods: In the study, 40 patients with secondary PAH were administered iNTG 2.5 μg/kg/min, IV NTG 2.5 μg/kg/min, a combination of iNTG 2.5 μg/kg/min + IV DOB 10 μg/kg/min, and IV NTG 2.5 μg/kg/min + IV DOB 10 μg/kg/min for 10 minutes each following valve replacement surgery, in random order. The hemodynamic parameters were recorded before (T0) and immediately after the intervention. (T1). Results: iNTG effectively decreased mean pulmonary arterial pressure (mPAP), pulmonary vascular resistance index (PVRI), and the PVR / SVR ratio, without affecting arterial pressures, systemic vascular resistance or mixed venous oxygen saturation (SvO 2 ). IV NTG produced both systemic and pulmonary vasodilation along with a significant fall in SvO 2 . The combination of iNTG and IV DOB caused a significant decrease in mPAP and PVRI, with no significant change in SVRI, PVR / SVR ratio, and SvO 2 . A combination of IV NTG + IV DOB caused both pulmonary and systemic vasodilatation with a significant decrease in SvO 2 . None of the drugs caused any significant change in the cardiac index. Conclusion: All drugs were of similar efficacy in reducing the pulmonary vascular resistance index. Only iNTG produced selective pulmonary vasodilatation, while IV NTG and its combination with IV dobutamine had a significant concomitant systemic vasodilatory effect.

Trans-esophageal echocardiography in off-pump coronary artery bypass grafting.

The two features of off-pump coronary artery bypass (OPCAB) grafting that lead to haemodynamic instability are, transient occlusion of the coronary arteries during distal anastomosis construction and displacement of the heart to provide access to the distal coronary arteries. The position of the heart as seen by trans-oesophageal echocardiography (TOE) can often provide an indication as to how much compression of the right or left ventricle has occurred. If either chamber is not filling, repositioning of the heart will be necessary. Close observation of the heart with TOE during periods of coronary occlusion may facilitate detection of worsening cardiac function as evidenced by weakening contraction, ventricular dilatation, or increasing mitral or tricuspid regurgitation. Haemodynamic change are more pronounced with displacement of the heart to access posterior than the anterior coronary arteries. Cardiac manipulations along with transient occlusion of coronary arteries during distal anastomosis may cause transient hypotension with increased filling pressures. TOE is helpful in this scenario as it helps to differentiate between cardiac dysfunction secondary to myocardial ischaemia (in which regional wall motion abnormalities will be present) from a much more common scenario where the increase in filling pressure is secondary to extra-cardiac compression and provides the ability to detect mitral regurgitation with a colour flow Doppler as well as assess the right heart function.