Strategies for blood conservation in pediatric cardiac surgery.

Cardiac surgery accounts for the majority of blood transfusions in a hospital. Blood transfusion has been associated with complications and major adverse events after cardiac surgery. Compared to adults it is more difficult to avoid blood transfusion in children after cardiac surgery. This article takes into account the challenges and emphasizes on the various strategies that could be implemented, to conserve blood during pediatric cardiac surgery

Early enteral nutrition therapy in congenital cardiac repair postoperatively: A randomized, controlled pilot study.

Background and Objectives: Adequate nutritional supplementation in infants with cardiac malformations after surgical repair is a challenge. Critically ill infants in the early postoperative period are in a catabolic stress. The mismatch between estimated energy requirement (EER) and the intake in the postoperative period is multifactorial, predisposing them to complications such as immune deficiency, more infection, and growth failure. This study aimed to assess the feasibility and efficacy of enriched breast milk feed on postoperative recovery and growth of infants after open heart surgery. Methodology: Fifty infants <6 months of age were prospectively randomized in the trial for enteral nutrition (EN) postoperatively from day 1 to 10, after obtaining the Institute Ethics Committee’s approval. They were equally divided into two groups on the basis of the feed they received: Control group was fed with expressed breast milk (EBM; 0.65 kcal/ml) and intervention group was fed with EBM + energy supplementation/fortification with human milk fortifier (7.5 kcal/2 g)/Simyl medium‑chain triglyceride oil (7.8 kcal/ml). Energy need for each infant was calculated as per EER at 90 kcal/kg/day, as the target requirement. The intra‑ and post‑operative variables such as cardiopulmonary bypass and aortic cross‑clamp times, ventilation duration, Intensive Care Unit (ICU), and hospital length of stay and mortality were recorded. Anthropometric and hematological parameters and infection control data were recorded in a predesigned pro forma. Data were analyzed using Stata 14.1 software. Results: The duration of mechanical ventilation, length of ICU stay (LOIS), length of hospital stay (LOHS), infection rate, and mortality rate were lower in the intervention group compared to the control group although none of the differences were statistically significant. Infants in control group needed mechanical ventilation for about a day more (i.e., 153.6 ± 149.0 h vs. 123.2 ± 107.0 h; P = 0.20) than those in the intervention group. Similarly, infants in control group stayed for longer duration in the ICU (13.2 ± 8.9 days) and hospital (16.5 ± 9.8 days) as compared to the intervention group (11.0 ± 6.1 days; 14.1 ± 7.0 days) (P = 0.14 and 0.17, respectively). The LOIS and LOHS were decreased by 2.2 and 2.4 days, respectively, in the intervention group compared to control group. The infection rate (3/25; 5/25) and mortality rate (1/25; 2/25) were lower in the intervention group than those in the control group. The energy intake in the intervention group was 40 kcal more (i.e., 127.2 ± 56.1 kcal vs. 87.1 ± 38.3 kcal) than the control group on the 10th postoperative day. Conclusions: Early enteral/oral feeding after cardiac surgery is feasible and recommended. In addition, enriching the EBM is helpful in achieving the maximum possible calorie intake in the postoperative period. EN therapy might help in providing adequate nutrition, and it decreases ventilation duration, infection rate, LOIS, LOHS, and mortality.

Acute kidney injury after pediatric cardiac surgery.

Acute kidney injury is a common complication after pediatric cardiac surgery. The definition, staging, risk factors, biomarkers and management of acute kidney injury in children is detailed in the following review article.

Incidence, microbiological profile of nosocomial infections, and their antibiotic resistance patterns in a high volume Cardiac Surgical Intensive Care Unit.

Background: Nosocomial infections (NIs) in the postoperative period not only increase morbidity and mortality, but also impose a significant economic burden on the health care infrastructure. This retrospective study was undertaken to (a) evaluate the incidence, characteristics, risk factors and outcomes of NIs and (b) identify common microorganisms responsible for infection and their antibiotic resistance profile in our Cardiac Surgical Intensive Care Unit (CSICU). Patients and Methods: After ethics committee approval, the CSICU records of all patients who underwent cardiovascular surgery between January 2013 and December 2014 were reviewed retrospectively. The incidence of NI, distribution of NI sites, types of microorganisms and their antibiotic resistance, length of CSICU stay, and patient‑outcome were determined. Results: Three hundred and nineteen of 6864 patients (4.6%) developed NI after cardiac surgery. Lower respiratory tract infections (LRTIs) accounted for most of the infections (44.2%) followed by surgical‑site infection (SSI, 11.6%), bloodstream infection (BSI, 7.5%), urinary tract infection (UTI, 6.9%) and infections from combined sources (29.8%). Acinetobacter, Klebsiella, Escherichia coli, and Staphylococcus were the most frequent pathogens isolated in patients with LRTI, BSI, UTI, and SSI, respectively. The Gram‑negative bacteria isolated from different sources were found to be highly resistant to commonly used antibiotics. Conclusion: The incidence of NI and sepsis‑related mortality, in our CSICU, was 4.6% and 1.9%, respectively. Lower respiratory tract was the most common site of infection and Gram‑negative bacilli, the most common pathogens after cardiac surgery. Antibiotic resistance was maximum with Acinetobacter spp.

The role of blood lactate clearance as a predictor of mortality in children undergoing surgery for tetralogy of Fallot.

Background: The identification of biomarkers for predicting morbidity and mortality, particularly in pediatric population undergoing cardiac surgery will contribute toward improving the patient outcome. There is an increasing body of literature establishing the clinical utility of hyperlactatemia and lactate clearance as prognostic indicator in adult cardiac surgical patients. However, the relationship between lactate clearance and mortality risk in the pediatric population remains to be established. Objective: To assess the role of lactate clearance in determining the outcome in children undergoing corrective surgery for tetralogy of Fallot (TOF). Methods and Study Design: A prospective, observational study. Setting: A tertiary care center. Study Population: Two hundred children undergoing elective surgery for TOF. Study Method: Blood lactate levels were obtained as baseline before operation (T0), postoperatively at admission to the cardiac intensive care unit after surgery (T1), and then at every 6 h for the first 24 h of Intensive Care Unit (ICU) stay (T6, T12, T18, and T24, respectively). The lactate clearance in the study is defined by the equation ([lactate initial – lactate delayed]/lactate initial) ×100%. Lactate clearance was determined at T1–T6, T1–T12, T1–T18, and T1–T24 time interval, respectively. The primary outcome measured was mortality. Secondary outcomes measured were the duration of mechanical ventilation, duration of inotropic requirement, and duration of ICU stay. Results: Eleven out of the two hundred patients enrolled in the study died. Nonsurvivors had higher postoperative lactate concentration (P < 0.05) and low‑blood lactate clearance rate during 24 h (P < 0.05) in comparison to the survivors. Lactate clearance was significantly higher in survivors than in nonsurvivors for the T1–T6 period (19.55 ± 14.28 vs. 5.24 ± 27.79%, P = 0.009) and remained significantly higher for each studied interval in first 24 h. Multivariate logistic regression analysis of statistically significant univariate variables showed early lactate clearance to have a significant relationship with mortality. Patients with a lactate clearance >10%, relative to patients with a lactate clearance <10%, in the early postoperative period, had improved outcome and lower mortality. Conclusion: Lactate clearance in the early postoperative period (6 h) is associated with decreased mortality rate. Patients with higher lactate clearance (>10%) after 6 h have improved outcome compared with those with lower lactate clearance.

Lactate clearance for initiating and weaning off extracorporeal membrane oxygenation in a child with regressed left ventricle after arterial switch operation.

We hereby report a child with transposition of great arteries and regressed ventricle who underwent arterial switch operation (ASO) with the aid of cardiopulmonary bypass and “integrated” extracorporeal membrane oxygenation (ECMO) circuit. The significance of lactate clearance as a guide to initiate and terminate veno-arterial ECMO in a post ASO child with regressed left ventricle is discussed.

Comparison of levosimendan and nitroglycerine in patients undergoing coronary artery bypass graft surgery.

Background: Levosimendan a calcium ion sensitizer improves both systolic and diastolic functions. This novel lusitropic drug has predictable antiischemic properties which are mediated via the opening of mitochondrial adenosine triphosphate‑sensitive potassium channels. This action of levosimendan is beneficial in cardiac surgical patients as it improves myocardial contractility, decreases systemic vascular resistance (SVR), and increases cardiac index (CI) and is thought to be cardioprotective. We decided to study whether levosimendan has any impact on the outcomes such as the duration of ventilation, the length of Intensive Care Unit (ICU) stay, and the hospital stay when compared with the nitroglycerine (NTG), which is the current standard of care at our center. Materials and Methods: Forty‑seven patients undergoing elective coronary artery bypass surgery were randomly assigned to two groups receiving either levosimendan or NTG. The medications were started before starting surgery and continued until 24 h in the postoperative period. Baseline hemodynamic parameters were evaluated before beginning of the operation and then postoperatively at 3 different time intervals. N‑terminal fragment of pro‑brain natriuretic peptide (NT‑proBNP) levels were also measured in both groups. Results: In comparison to the NTG group, the duration of ventilation and length of ICU stay were significantly less in levosimendan group (P < 0.05, P = 0.02). NT‑proBNP level analysis showed a slow rising pattern in both groups and a statistically significant rise in the levels was observed in NTG group (P = 0.03, P = 0.02) in postoperative period when compared to levosimendan group of patients. Conclusion: Levosimendan treatment in patients undergoing surgical revascularization resulted in improved CI, decreased SVR and lower heart rate. And, thereby the duration of ventilation and length of ICU stay were significantly less in this group of patients when compared with NTG group.

Use of dexmedetomidine as an adjunct in the treatment of paradoxical hypertension after surgical repair of coarctation of the aorta in infants.

Severe persistent hypertension is seen infrequently in newborns and infants, but we came across two infants who developed severe paradoxical hypertension after successful coarctation repair. Treatment of systemic hypertension following repair of coarctation of the aorta is always challenging particularly in infants. Dexmedetomidine was used successfully as an adjunct to the established anti‑hypertensive drugs in the immediate postoperative period in our cases to treat postoperative paradoxical hypertension.

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.

Comparison of S100β levels, and their correlation with hemodynamic indices in patients undergoing coronary artery bypass grafting with three different anesthetic techniques.

Cardiac surgery with aid of cardiopulmonary bypass (CPB) is associated with neurological dysfunction. The presence of cerebrospecific protein S100β in serum is an indicator of cerebral damage. This study was designed to evaluate the influence of three different anesthesia techniques, on S100β levels, in patients undergoing coronary artery bypass grafting on CPB. A total of 180 patients were divided into three groups - each of who received sevoflurane, isoflurane and total intravenous anesthesia as part of the anesthetic technique, respectively. S100 were evaluated from venous sample at following time intervals - prior to induction of anesthesia (T1), after coming off CPB (T2); 12 h after aortic cross clamping (T3) and 24 h after aortic cross clamping (T4). In all three groups, maximal rise in S100β levels occurred after CPB which gradually declined over next 24 h, the levels at 24 h post-AOXC being significantly higher than baseline levels. Significantly low levels of S100β were noted at all postdose hours in the sevoflurane group, as compared to the total intravenous anesthesia (TIVA) group, and at 12 and 24 h postaortic cross clamp, in comparison to the isoflurane group. Comparing the isoflurane group with the TIVA group, the S100 levels were lower in the isoflurane group only at 24 h postaortic cross clamp. It was concluded that maximum rise in S100β levels occurs immediately after CPB with a gradual decline in next 24 h. The rise in S100β levels is significantly less in patients administered sevoflurane in comparison to isoflurane or TIVA. Hemodynamic parameters had no influence on the S100β levels during the first 24 h after surgery.

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.