Pediatric Patients Undergoing Heart Surgery Research Articles

Tracheal surgery for airway anomalies associated with increased mortality in pediatric patients undergoing heart surgery: Society of Thoracic Surgeons Database analysis

ObjectivesAirway anomalies are common in children with cardiac disease but with an unquantified impact on outcomes. We sought to define the association between airway anomalies and tracheal surgery with cardiac surgery outcomes using the Society of Thoracic Surgery Congenital Heart Surgery Database. MethodsIndex cardiac operations in children aged less than 18 years (January 2010 to September 2018) were identified from the Society of Thoracic Surgery Congenital Heart Surgery Database. Patients were divided on the basis of reported diagnosis of an airway anomaly and subdivided on the basis of tracheal lesion and tracheal surgery. Multivariable analysis evaluated associations between airway disease and outcomes controlling for covariates from the Society of Thoracic Surgery Congenital Heart Surgery Database Mortality Risk Model. ResultsOf 198,674 index cardiovascular operations, 6861 (3.4%) were performed in patients with airway anomalies, including 428 patients (0.2%) who also underwent tracheal operations during the same hospitalization. Patients with airway anomalies underwent more complex cardiac operations (45% vs 36% Society of Thoracic Surgeons/European Association for Cardiothoracic Surgery Congenital Heart Surgery Mortality category ≥3 procedures) and had a higher prevalence of preoperative risk factors (73% vs 39%; both P < .001). In multivariable analysis, patients with airway anomalies had increased odds of major morbidity and tracheostomy (P < .001). Operative mortality was also increased in patients with airway anomalies, except those with malacia. Tracheal surgery within the same hospitalization increased the odds of operative mortality (adjusted odds ratio, 3.9; P < .0001), major morbidity (adjusted odds ratio, 3.7; P < .0001), and tracheostomy (adjusted odds ratio, 16.7; P < .0001). ConclusionsPatients undergoing cardiac surgery and tracheal surgery are at significantly higher risk of morbidity and mortality than patients receiving cardiac surgery alone. Most of those with unoperated airway anomalies have higher morbidity and mortality, which makes it an important preoperative consideration.

Cellular and Molecular Mechanisms of Low Cardiac Output Syndrome after Pediatric Cardiac Surgery.

Several cellular and molecular mechanisms have been implicated in the development of myocardial dysfunction and low cardiac output in pediatric patients undergoing heart surgery. Ischemia- reperfusion injury with alterations in calcium homeostasis as well as mitochondrial function has been strongly related to myocyte damage and heart failure in this population. In this article, we will review the main mechanisms of postoperative cardiac dysfunction at cellular and molecular levels and the subsequent protective strategies. In addition, we will describe cellular features of the neonatal or immature myocardium and will suggest possible protective management strategies. This article addresses the first of eight topics comprising the special issue entitled "Pharmacologic strategies with afterload reduction in low cardiac output syndrome after pediatric cardiac surgery".

Apolipoprotein E levels in pediatric patients undergoing cardiopulmonary bypass.

Apolipoprotein E (apoE) may play a critical role in modulating the response to neurological injury after cardiopulmonary bypass (CPB) in children. Plasma samples were collected from 38 pediatric patients. Half of the patients received nonpulsatile flow and the other half underwent pulsatile flow during CPB. Plasma samples were collected at three time points: at baseline prior to incision (T1), 1 h after CPB (T2), and 24 h after CPB (T3). The study included 38 pediatric patients undergoing heart surgery (mean age 2.5 ± 2.1 years). Baseline apoE levels were low (<30 μg/mL) in 21 patients (55%). ApoE levels were significantly decreased at 1 h after CPB compared with baseline (22 ± 14 vs. 34 ± 18 μg/mL, P = 0.001). At 24 h after CPB, apoE levels were significantly increased compared with baseline (47 ± 25 vs. 34 ± 18 μg/mL, P = 0.002). Pulsatile mode was associated with lower apoE levels at 24 h after CPB compared with nonpulsatile mode (38 ± 14 vs. 57 ± 29 μg/mL, P = 0.018). ApoE levels correlated negatively with pump time (r = -0.525, P = 0.021) and cross-clamp time (r = -0.464, P = 0.045) at 24 h following CPB for the nonpulsatile group but not for the pulsatile group. In this cohort of young children with congenital heart disease, baseline apoE levels were low in the majority of patients prior to surgery. ApoE levels decreased further at 1 h after CPB, and then significantly increased by 24 h. The mode of perfusion and the duration of pump time and clamp time influence the apoE levels after CPB. An improved understanding of these mechanisms may translate into the development of new techniques to improve the clinical outcomes after pediatric CPB.

Impact of the insulin and glucose content of the postoperative fluid on the outcome after pediatric cardiac surgery.

The aim of this study was to investigate the role of the insulin and glucose content of the maintenance fluid in influencing the outcomes of pediatric patients undergoing heart surgery. A total of 2063 consecutive pediatric patients undergoing cardiac surgery were screened between 2003 and 2008. A dextrose and an insulin propensity-matched group were constructed. In the dextrose model, 5% and 10% dextrose maintenance infusions were compared below 20 kg of weight. A total of 171 and 298 pairs of patients were matched in the insulin and glucose model, respectively. Mortality was lower in the insulin group (12.9% vs. 7%, p = 0.049). The insulin group had longer intensive care unit (ICU) stay [days, 10.9 (5.8-18.4) vs. 13.7 (8.2-21), p = 0.003], hospital stay [days, 19.8 (13.6-26.6) vs. 22.7 (17.6-29.7), p < 0.01], duration of mechanical ventilation [hours, 67 (19-140) vs. 107 (45-176), p = 0.006], and the incidence of severe infections (18.1% vs. 28.7%, p = 0.01) and dialysis (11.7% vs. 24%, p = 0.001) was higher. In the dextrose model, the incidence of pulmonary complications (13.09% vs. 22.5%, p < 0.01), low cardiac output (17.11% vs. 30.9%, p < 0.01), and severe infections (10.07% vs. 20.5%, p < 0.01) was higher, and the duration of the hospital stay [days, 16.4 (13.1-21.6) vs. 18.1 (13.8-24.6), p < 0.01] was longer in the 10% dextrose group. Insulin treatment appeared to decrease mortality, and lower glucose content was associated with lower occurrence of adverse events.

The impact of human rhinovirus infection in pediatric patients undergoing heart surgery.

Human rhinovirus (HRV), the most common cause of upper respiratory infection in children, can present as bronchiolitis, pneumonia, or asthma exacerbations. The impact of HRV in infants and toddlers with congenital heart disease is poorly defined. A case-control study was performed to compare the clinical course for 19 young children with respiratory symptoms who tested positive for rhinovirus after heart surgery with that of 56 matched control subjects. The control subjects were matched by surgical repair, age, weight, and time of the year. Patients with known HRVs before surgery and control subjects with respiratory symptoms or positive test results for viruses were excluded from the study. Human rhinovirus infection was associated with more than a tenfold increase in the odds of noninvasive ventilation after extubation (odds ratio [OR] 11.45; 95 % confidence interval [CI] 3.97-38.67), a 12-fold increase in the probability of extubation failure (OR 12.84; 95 % CI 2.93-56.29), and increased use of pulmonary medications including bronchodilator and nitric oxide (p < 0.001). As a result, the hospital length of stay (HLOS) was two times longer than for the control subjects (p < 0.001), and the cardiac intensive care unit (CICU) length of stay (CICU LOS) was three times longer (p < 0.0001). The intubation time was significantly longer (p < 0.001), and the CICU respiratory charges were significantly greater (p = 0.001) for the infected patients. Human rhinovirus increases resource use and prolongs postoperative recovery after pediatric heart surgery. Surgery timing should be delayed for patients with rhinovirus if possible.

Adiponectin plasma levels decrease after surgery in pediatric patients with congenital heart disease

ObjectiveAdiponectin is a protein secreted by adipose tissue and involved in inflammatory process as well as in metabolic regulation. The aim of this study was to examine the response of plasma adiponectin to cardiac surgery in children with congenital defects to determine whether its measurement is associated to the response to injury. Design and methodsTwenty-five pediatric patients undergoing heart surgery for correction of congenital defects were studied. Adiponectin plasma levels, obtained pre- and three times postoperatively, were determined by dedicated ELISA. Brain natriuretic peptide (BNP) plasma levels were also determined. ResultsAdiponectin levels are highest in the first month of life (p=0.004 newborns vs. children) with a progressive fall in the next few years. After surgery, adiponectin increased slowly over a 1-month period, following an initial decrease in the first 3days. ConclusionsAdiponectin could be involved in the acute response to injury although further investigation into the relationship between adiponectin, glucose regulation and inflammatory process is necessary to examine the issue of the adiponectin decrease after surgery from a more integrated prospective.

Evaluation of the Duration of the Antibiotic Prophylaxis in Paediatric Postoperative Heart Surgery Patients

The ideal duration of postoperative antibiotic prophylaxis in heart surgery is unknown. The most recent guidelines recommend a decrease in prophylaxis time to decrease the emergence of multiresistant germs. However, compliance with these recommendations is scant. Our aim was to determine whether a decrease in prophylaxis time entails an increase in the infection rate. A retrospective study was performed between September 2003 and March 2006, including all patients of ages between 1 day and 14 years who were admitted to the intensive care unit after heart surgery. Patients being treated for an infection at the time of surgery were excluded. The appearance of nosocomial infection, localisation, and the causative agent, if isolated, were included; demographic and clinical analytical variables, duration and type of antibiotic prophylaxis, and duration of other invasive devices were also included. Standard analysis and multivariable logistical regression were performed. 194 patients were included in the study. The median duration of antibiotic prophylaxis was 72 h (range 24 to 176), with the most-used prophylaxis regimen being second-generation cephalosporins plus aminoglycosides. The incidence of nosocomial infection, mainly bacteraemia, was 11.9%. The type of antibiotic therapy used for prophylaxis did not affect the incidence of infection. In the multivariable logistical regression, only prolongation of antibiotic prophylaxis >48 h, central venous access maintenance time, and intubation increased the infection rate. The suspension of antibiotic prophylaxis in the 48 h after surgery in pediatric patients undergoing heart surgery does not increase the incidence of nosocomial infection. According to our results, prolongation of prophylaxis >48 h increases the infection rate.

Acute Kidney Injury Is Associated With Higher Morbidity and Resource Utilization in Pediatric Patients Undergoing Heart Surgery

The RIFLE (risk, injury, failure, loss, and end-stage renal disease) classification system was developed to standardize the definition of acute kidney injury (AKI) in adults. We hypothesized that AKI was associated with increased mortality and morbidity. Acute kidney injury was defined as a decrease in the amount of estimated creatinine clearance based on pediatric-modified RIFLE (pRIFLE) criteria. Using propensity score analysis, 325 patients who had AKI were matched to 325 patients who did not have AKI from a database of 1,510 consecutive pediatric patients who underwent cardiac surgery between January 2004 and December 2008 at a single center. The association between AKI and outcome was analyzed after propensity score matching of perioperative variables. Four hundred eighty-one patients (31.9%) had AKI according to the RIFLE categories. Of those 1,510, 173 (11.5%) reached pRIFLE criteria for risk; 26 (1.7%) reached the criteria for injury; and 282 (18.7%) reached the criteria for failure. Fifty-five patients (3.6%) died. The 2 matched groups were well balanced in terms of measured perioperative variables. Mortality rate was 5.2% in the AKI and 2.5% in the matched control group (p=0.09). Occurrence of low cardiac output syndrome (p=0.002), need for dialysis (p<0.001), and infection (p=0.03) were significantly higher, and duration of mechanical ventilation (p<0.001) and length of intensive care unit stay (p<0.001) were significantly longer compared with the matched control group. Acute kidney injury was independently associated with an increased occurrence of postoperative complications but not with mortality after pediatric cardiac surgery.

Near-infrared spectroscopy cerebral and somatic (renal) oxygen saturation correlation to continuous venous oxygen saturation via intravenous oximetry catheter

PurposeNear-infrared spectroscopy (NIRS) and continuous central venous oxygen saturation (ScvO2) via oximetry catheter are 2 modalities available to estimate adequacy of oxygen delivery in postoperative pediatric cardiac patients. Near-infrared spectroscopy measures regional tissue oxygenation and is routinely used in pediatric cardiac surgery patients. By not requiring an invasive catheter, NIRS has the advantage over mixed venous oxygen saturation (SvO2) monitoring. An alternative marker of global tissue oxygenation is central venous oxygen saturation (ScvO2). A recently developed pediatric-sized oximetric catheter (PediaSat; Edwards Lifesciences, Irvine, CA, USA) functions as a central venous catheter and provides a continuous ScvO2 reading, an accepted surrogate to SvO2. To date, the correlation between NIRS and ScvO2 has not been quantified. The aim of this study was to examine the strength of the bivariate correlation between NIRS and ScvO2 measurements. Design/methodsTwenty pediatric patients undergoing cardiac surgery had the PediaSat catheter placed with the tip in the superior vena cava and NIRS sensors (cerebral and renal) placed in the operating room per routine protocol. Hourly measurements of NIRS-cerebral (NIRS-C), NIRS-renal, and ScvO2 readings were recorded for each patient for up to 48 hours postoperatively. ResultsA cumulative total of 630 hours of data were collected. Spearman correlation coefficients for NIRS-renal vs ScvO2 and NIRS-C vs ScvO2 measurements were r = 0.38 (P = .09) and r = 0.58 (P < .008), respectively. ConclusionsIn this small cohort of pediatric patients undergoing heart surgery, there was a moderate but statistically significant correlation between the ScvO2-catheter and the NIRS-C values. Further studies are required to determine which oxymetric modality of monitoring cardiac output most aids in the postoperative management of these patients.

Magnesium supplementation in the prevention of arrhythmias in pediatric patients undergoing surgery for congenital heart defects

Background The efficacy of magnesium in the prevention of arrhythmias in pediatric patients after heart surgery remains unknown. Therefore we prospectively examined the effect of magnesium treatment on the incidence of postoperative arrhythmias in pediatric patients undergoing surgical repair of congenital heart defects. Methods and Results Twenty-eight pediatric patients undergoing heart surgery with cardiopulmonary bypass were prospectively, randomly assigned in a double-blind fashion to receive intravenous magnesium (magnesium group, n = 13; 30 mg/kg) or saline (placebo group, n = 15) immediately after cessation of cardiopulmonary bypass. Magnesium, potassium, and calcium levels were measured at defined intervals during surgery and 24 hours after surgery. Continuous electrocardiographic documentation by Halter monitor was performed for 24 hours after surgery. Magnesium levels were significantly decreased below the normal reference range for patients in the placebo group compared with the magnesium group on arrival in the intensive care unit and for 20 hours after surgery. Magnesium levels remained in the normal range for patients in the magnesium group after magnesium supplementation. In 4 patients in the placebo group (27%), junctional ectopic tachycardia developed within the initial 20 hours in the intensive care unit. No junctional ectopic tachycardia was observed in the magnesium group ( P = .026). Conclusions Although this study was originally targeted to include 100 patients, the protocol was terminated because of the unacceptable incidence of hemodynamically significant junctional ectopic tachycardia that was present in the placebo group. Thus low magnesium levels in pediatric patients undergoing heart surgery are associated with an increased incidence of junctional ectopic tachycardia in the immediate postoperative period.

The Inflammatory Response to Pediatric Cardiac Surgery: Correlation of Granulocyte Adhesion Molecule Expression with Postoperative Oxygenation

The Inflammatory Response to Pediatric Cardiac Surgery: Correlation of Granulocyte Adhesion Molecule Expression with Postoperative Oxygenation