Bleeding in the lung complicates a routine intracardiac repair: What went wrong!!!

Cyanotic congenital heart disease presents an increased tendency to bleed in view of subtle coagulation defects. Airway bleeding can be particularly difficult to manage while maintaining an adequate ventilation. An isolated lung bleed with the exclusion of possible traumatic, medical and surgical causes of bleeding, should alert the attending anesthesiologist to the possibility of the collateral-related bleeding. Preoperative coil embolization remains an important initial management step in a case of tetralogy of Fallot (TOF) with major aortopulmonary collaterals. Nevertheless, the coiling of the collaterals in certain specific case scenarios is not feasible, rendering the management of a lung bleed, all the more challenging. We, hereby discuss a case of a 7-year-old girl with a massive endotracheal bleed at the time of weaning from cardiopulmonary bypass after corrective surgery for TOF. The subsequent approach and management are discussed. The optimal management of tetralogy with collaterals mandates an effective communication among the cardiologist, radiologist, anesthesiologist, and the surgeon.

Modified Blalock Taussig shunt: Comparison between neonates, infants and older children.

Objective: The aim was to compare various pre-and post-operative parameters and to identify the predictors of mortality in neonates, infants, and older children undergoing Modifi ed Blalock Taussig shunt (MBTS). Materials and Methods: Medical records of 134 children who underwent MBTS over a period of 2 years through thoracotomy were reviewed. Children were divided into three groups-neonates, infants, and older children. For analysis, various pre-and post-operative variables were recorded, including complications and mortality. Results: The increase in PaO2 and SaO2 levels after surgery was similar and statistically signifi cant in all the three groups. The requirement of adrenaline, duration of ventilation and mortality was signifi cantly higher in neonates. The overall mortality and infant mortality was 4.5% and 8%, respectively. Conclusion: Neonates are at increased risk of complications and mortality compared with older children. Age (<30 days), weight (<3 kg), packed red blood cells transfusion >6 ml/kg, mechanical ventilation >24 h and post shunt increase in PaO2 (PDiff) <25% of baseline PaO2 are independent predictors of mortality in children undergoing MBTS.

Utility of Sonoclot analysis and tranexamic acid in tetralogy of Fallot patients undergoing intracardiac repair.

Sonoclot analysis is a point of care test to monitor the coagulation process, presenting a comprehensive evaluation of the clot formation and retraction as well as platelet function. This randomized double-blinded study was designed to investigate the utility of Sonoclot analysis in monitoring the coagulation profile as also the antifibrinolytic effects of tranexamic acid administered in patients with tetralogy of Fallot undergoing intracardiac repair. Eighty of a total 94 patients were randomly divided into two groups of 40 each. In the study group, TA was administered thrice at a dosage of 10 mg/kg, i.e. before CPB, on CPB and after CPB, whereas in the control group, placebo was administered at the same time intervals. Sonoclot analysis and D-dimer measurement were performed at baseline and following heparin neutralisation. An additional variable, DR 15 (diminishing rate of clot strength at 15 min postmaximal clot strength), was calculated from the Sonoclot graph and was compared with d-dimer levels as a measure of fibrinolysis. The three Sonoclot variables, i.e. activated clotting time, clot rate and platelet function, were deranged at baseline in all the patients. Post-CPB, the change in these variables was not significant. ACT, clot rate and platelet function showed no significant (P > 0.05) difference in both the groups at both the time intervals. DR 15 and d-dimer values were comparable at baseline in both the groups. However, a significant (P < 0.05) difference was seen in these variables in the control group as compared with the TA group following heparin neutralisation. To conclude, Sonoclot analysis is a useful, point of care method for the monitoring of coagulation and fibrinolysis in patients with tetralogy of Fallot undergoing intracardiac repair.

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.

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.

Comparison of B-type natriuretic peptide and left ventricular dysfunction in patients with constrictive pericarditis undergoing pericardiectomy.

Chronic constrictive pericarditis (CCP) due to tuberculosis has high morbidity and mortality in the periopeartive period following pericardiectomy because of left ventricular (LV) dysfunction. Brain-type natriuretic peptide (BNP) is considered a marker for both LV systolic and diastolic dysfunction. We undertook this prospective study in 24 patients, to measure the BNP levels and to compare it with transmitral Doppler flow velocities, that is, the E/A ratio (E = initial peak velocity during early diastolic filling and A = late peak flow velocity during atrial systole), as a marker of diastolic function and systolic parameters, pre- and post-pericardiectomy, at the time of discharge. The latter parameters have been taken as a flow velocity across the mitral valve on a transthoracic echo. There was a significant decrease in the mean values of log BNP (6.19 ± 0.33 to 4.65 ± 0.14) (P = 0.001) and E/A ratio (1.81 ± 0.21 to 1.01 ± 0.14) (P = 0.001) post pericardiectomy, with a positive correlation, r = 0.896 and 0.837, respectively, between the two values at both the time periods. There was significant improvement in the systolic parameters of the LV function, that is, stroke volume index, cardiac index, systemic vascular resistance index, and delivered oxygen index. However, no correlation was observed between these values and the BNP levels. We believe that BNP can be used as a marker for LV diastolic dysfunction in place of the E/A ratio in patients with CCP, undergoing pericardiectomy. However, more studies have to be performed for validation of the same.

Early goal-directed therapy in moderate to high-risk cardiac surgery patients.

Early goal-directed therapy is a term used to describe the guidance of intravenous fluid and vasopressor/inotropic therapy by using cardiac output or similar parameters in the immediate post-cardiopulmonary bypass in cardiac surgery patients. Early recognition and therapy during this period may result in better outcome. In keeping with this aim in the cardiac surgery patients, we conducted the present study. The study included 30 patients of both sexes, with EuroSCORE >or=3 undergoing coronary artery bypass surgery under cardiopulmonary bypass. The patients were randomly divided into two groups, namely, control and early goal-directed therapy (EGDT) groups. All the subjects received standardized care; arterial pressure was monitored through radial artery, central venous pressure through a triple lumen in the right internal jugular vein, electrocardiogram, oxygen saturation, temperature, urine output per hour and frequent arterial blood gas analysis. In addition, cardiac index monitoring using FloTrac and continuous central venous oxygen saturation using PreSep was used in patients in the EGTD group. Our aim was to maintain the cardiac index at 2.5-4.2 l/min/m2 , stroke volume index 30-65 ml/beat/m2 , systemic vascular resistance index 1500-2500 dynes/s/cm5/m2 , oxygen delivery index 450-600 ml/min/m2 , continuous central venous oximetry more than 70%, stroke volume variation less than 10%; in addition to the control group parameters such as central venous pressure 6-8 mmHg, mean arterial pressure 90-105 mmHg, normal arterial blood gas analysis values, pulse oximetry, hematocrit value above 30% and urine output more than 1 ml/kg/h. The aims were achieved by altering the administration of intravenous fluids and doses of inotropic or vasodilator agents. Three patients were excluded from the study and the data of 27 patients analyzed. The extra volume used (330+/-160 v/s 80+/-80 ml, P=0.043) number of adjustments of inotropic agents (3.4+/-1.5 v/s 0.4+/-0.7, P=0.026) in the EGDT group were significant. The average duration of ventilation (13.8+/-3.2 v/s 20.7+/-7.1 h), days of use of inotropic agents (1.6+/-0.9 v/s 3.8+/-1.6 d), ICU stay (2.6+/-0.9 v/s 4.9+/-1.8 d) and hospital stay (5.6+/-1.2 v/s 8.9+/-2.1 d) were less in the EGDT group, compared to those in the control group. This study is inconclusive with regard to the beneficial aspects of the early goal-directed therapy in cardiac surgery patients, although a few benefits were observed.