Cardiopulmonary Bypass In Children Research Articles

Effect of static lung expansion on pulmonary function following cardiopulmonary bypass in children

ObjectiveTo observe the effect of the lung-protective ventilation strategy, static lung expansion, during cardiopulmonary bypass (CPB) on pulmonary function and tracheal intubation time following cardiac surgery in children. MethodsA total of 48 child patients (aged 1–3) with ventricular septal defect (VSD) were enrolled, and all underwent CPB cardiac surgery for the first time. The patients were divided into two groups using the random number table method: the experimental group (Group A, n = 30) and the control group (Group B, n = 18). After terminating the mechanical ventilation during CPB, the adjustable pressure limiting valve of the anesthesia machine was adjusted in the experimental group to maintain the pressure of the breathing circuit at 5 cmH2O, such that both lungs remained in a static expansion state. In the control group, routine mechanical ventilation was terminated as usual. ResultsWhen static lung expansion with a continuous positive airway pressure of 5 cmH2O was employed in the VSD children during CPB, compared with termination of mechanical ventilation, the partial pressure of oxygen in the arterial blood increased, while the respiratory index decreased and the oxygenation index increased following the surgery. ConclusionIn child patients undergoing VSD reparation under CPB, lung injury occurs following the procedure, and the pulmonary oxygenation function and pulmonary oxygen diffusion function decrease. When static lung expansion of 5 cmH2O is performed during CPB, the improvement in lung function is better than that of apnea without lung expansion pressure.

Probiotics may alleviate intestinal damage induced by cardiopulmonary bypass in children.

Intestinal ischaemia-reperfusion injury induced by cardiopulmonary bypass causes intestinal epithelial barrier dysfunction, leading to dysbiosis and bacterial translocation. We conducted a randomized prospective study with 2 objectives: (i) to investigate epithelial barrier dysfunction and bacterial translocation induced by cardiopulmonary bypass and changes in the gut microbiota and (ii) to verify whether probiotics can improve these conditions. Between 2019 and 2020, patients 0-15 years old scheduled to undergo cardiac surgery using cardiopulmonary bypass were enrolled and randomly allocated to 2 groups: the intervention group received probiotics and the control group did not receive probiotics. We analysed the microbiota in faeces and blood, organic acid concentrations in faeces, plasma intestinal fatty acid-binding protein and immunological responses. Eighty-two patients were enrolled in this study. The characteristics of the patients were similar in both groups. The total number of obligate anaerobes was higher in the intervention group than in the control group after postoperative day 7. We identified 4 clusters within the perioperative gut microbiota, and cluster changes showed a corrective effect of probiotics on dysbiosis after postoperative day 7. Organic acid concentrations in faeces, incidence of bacterial translocation, intestinal fatty acid-binding protein levels and immunological responses, except for interleukin -17A, were not markedly different between the 2 groups. Administration of probiotics was able to correct dysbiosis but did not sufficiently alleviate the intestinal damage induced by cardiopulmonary bypass. More effective methods should be examined to prevent disturbances induced by cardiac surgery using cardiopulmonary bypass. https://center6.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000037174 UMIN000035556.

Risk factors of gastrointestinal bleeding after cardiopulmonary bypass in children: a retrospective study.

During cardiac surgery that involved cardiopulmonary bypass (CPB) procedure, gastrointestinal (GI) system was known to be vulnerable to complications such as GI bleeding. Our study aimed to determine the incidence and risk factors associated with GI bleeding in children who received CPB as part of cardiac surgery. This retrospective study enrolled patients aged <18 years who underwent cardiac surgery with CPB from 2013 to 2019 at Shanghai Children's Medical Center. The primary outcome was the incidence of postoperative GI bleeding in children, and the associated risk factors with postoperative GI bleeding episodes were evaluated. A total of 21,893 children who underwent cardiac surgery with CPB from 2013 to 2019 were included in this study. For age distribution, 636 (2.9%) were neonates, 10,984 (50.2%) were infants, and 10,273 (46.9%) were children. Among the 410 (1.9%) patients with GI bleeding, 345 (84.2%) survived to hospital discharge. Incidence of GI bleeding in neonates, infants and children were 22.6% (144/636), 2.0% (217/10,984) and 0.5% (49/10,273), respectively. The neonates (22.6%) group was associated with highest risk of GI bleeding. Patients with GI bleeding showed longer length of hospital stays (25.8 ± 15.9 vs. 12.5 ± 8.9, P < 0.001) and higher mortality (15.9% vs. 1.8%, P < 0.001). Multivariate logistic regression analysis showed that age, weight, complicated surgery, operation time, use of extracorporeal membrane oxygenation (ECMO), low cardiac output syndrome (LCOS), hepatic injury, artery lactate level, and postoperative platelet counts were significantly associated with increased risk of GI bleeding in children with congenital heart disease (CHD) pediatric patients that underwent CPB procedure during cardiac surgery. The study results suggest that young age, low weight, long operation time, complicated surgery, use of ECMO, LCOS, hepatic injury, high arterial lactate level, and low postoperative platelet counts are independently associated with GI bleeding after CPB in children.

Comparison of Prothrombin Complex Concentrate with Activated Factor VII Use for Bleeding Following Cardiopulmonary Bypass in Children.

This study aims to compare the efficacy and safety of activated recombinant factor VII (rFVIIa) and prothrombin complex concentrate (PCC) in the treatment of bleeding complications following surgery requiring cardiopulmonary bypass (CPB) in children. This is a retrospective chart review of a single institution comprising patients aged 0 to 18 years old with congenital heart disease. Patients must have received either PCC or rFVIIa after coming off CPB. Our primary efficacy endpoint is time in the operating room from off-CPB to pediatric intensive care unit admission. Our primary safety endpoint is thrombosis through 30 days. Our primary efficacy outcome was significantly shorter in the PCC group compared with the rFVIIa group (P < .0001). Similarly, secondary efficacy outcomes of packed red blood cell administration, chest tube output, and transfusion exposures all significantly favored PCC administration. However, CPB time was significantly longer, and body temperatures were significantly lower, in the rFVIIa group. Safety outcomes, including our primary safety outcome of thrombosis through 30 days, were similar between the two groups. This study questions whether PCC could be favored over rFVIIa for hemostasis in children with congenital heart disease following CPB surgery. In addition, this study has found no difference when comparing PCC and rFVIIa in terms of safety outcomes, particularly thrombosis events. There are several limitations to this study due to the retrospective nature of the design and the differences between the two study groups. Despite the limitations, this study suggests that relatively early administration of PCC could be favored over delayed administration of rFVIIa to control recalcitrant post-CPB bleeding in the operating room.

Factors Associated With Acute Kidney Injury After Cardiopulmonary Bypass in Children.

Acute kidney injury (AKI) is a common complication after cardiovascular surgery in children, noted in approximately 40% of children undergoing cardiopulmonary bypass (CPB). We sought to determine the risk factors including inflammatory and vascular endothelial markers associated with AKI in children undergoing cardiac surgery. A secondary analysis of a prospective observational cohort study of paediatric patients with a cardiac defect requiring CPB and a weight of >2.5 kg was performed. AKI was defined as a 1.5 times increase from the preoperative value in serum creatinine or an absolute increase by ≥0.3 mg/dL (≥26.5 μmol/L). Plasma inflammatory markers (interleukin [IL]-1a, IL-1b, IL-2, IL-4, IL-6, IL-8, IL-10, IL-12p70, and tumour necrosis factor α) and vascular endothelial markers (vascular endothelial growth factor, von Willebrand factor, regulated on activation, normal T-cell expressed and secreted, granulocyte macrophage colony-stimulating factor, monocyte chemoattractant protein-1, platelet-derived growth factor, and microparticles) were assessed at 5 perioperative time points. Associations with AKI were found using generalized linear regression models adjusted for repeated measures. A total of 207 patients were assessed, of whom 56% (n= 116) were male. Thirty-three percent (n= 68) developed AKI. In univariable analyses, adverse outcomes significantly related to the presence of AKI included increased intensive care unit stay (3.0 vs 5.6 hours, P < 0.001). In multivariable analysis, independent factors that were significantly associated with AKI included longer duration of CPB (111 vs 154 minutes, P < 0.001) and lower preoperative creatinine. Inflammatory and vascular endothelial biomarkers were not associated with AKI. AKI remains a prevalent problem after cardiac surgery, and renal ischemia related to longer bypass time potentially plays a key role in the etiology. Inflammatory and vascular endothelial biomarkers were not significantly related to AKI.

Con: Modified Ultrafiltration Should Not Be Routinely Used in Adult Cardiac Surgery

CARDIOPULMONARY BYPASS (CPB) is known to induce a systemic proinflammatory state and may contribute to postoperative organ dysfunction, primarily through complement activation secondary to blood passing through an artificial extracorporeal circuit. 1 Hall RI Smith MS Rocker G. The systemic inflammatory response to cardiopulmonary bypass: Pathophysiological, therapeutic, and pharmacological considerations. Anesth Analg. 1997; 85: 766-782 Crossref PubMed Google Scholar , 2 Wang W Huang HM Zhu DM et al. Modified ultrafiltration in paediatric cardiopulmonary bypass. Perfusion. 1998; 13: 304-310 Crossref PubMed Scopus (39) Google Scholar , 3 Thapmongkol S Masaratana P Subtaweesin T et al. The effects of modified ultrafiltration on clinical outcomes of adult and pediatric cardiac surgery. Asian Biomedicine. 2015; 9: 591-599 Crossref Scopus (4) Google Scholar Ultrafiltration may minimize some of the impact of the CPB-induced systemic inflammatory response. 4 Huang H Yao T Wang W et al. Continuous ultrafiltration attenuates the pulmonary injury that follows open heart surgery with cardiopulmonary bypass. Ann Thorac Surg. 2003; 76: 136-140 Abstract Full Text Full Text PDF PubMed Scopus (85) Google Scholar Traditionally, ultrafiltration may be conventional (CUF) or modified (MUF). Conventional ultrafiltration has been employed extensively during CPB, and involves hemoconcentration of both the priming volume and patient's blood volume at any point during CPB. 5 Darup J Bleese N Kalmar P et al. Hemofiltration during extracorporeal circulation (ECC). Thorac Cardiovasc Surg. 1979; 27: 227-230 Crossref PubMed Scopus (30) Google Scholar ,6 Klineberg PL Kam CA Johnson DC et al. Hematocrit and blood volume control during cardiopulmonary bypass with the use of hemofiltration. Anesthesiology. 1984; 60: 478-480 Crossref PubMed Scopus (19) Google Scholar In the early 1990s, Naik et al. introduced the concept of MUF 7 Elliott MJ. Ultrafiltration and modified ultrafiltration in pediatric open heart operations. Ann Thorac Surg. 1993; 56: 1518-1522 Abstract Full Text PDF PubMed Scopus (205) Google Scholar ,8 Andreasson S Gothberg S Berggren H et al. Hemofiltration modifies complement activation after extracorporeal circulation in infants. Ann Thorac Surg. 1993; 56: 1515-1517 Abstract Full Text PDF PubMed Scopus (88) Google Scholar ,9 Naik SK Knight A Elliott MJ. A successful modification of ultrafiltration for cardiopulmonary bypass in children. Perfusion. 1991; 6: 41-50 Crossref PubMed Scopus (164) Google Scholar in which the patient's blood volume is hemoconcentrated after separation from CPB. 10 Wang S Palanzo D Undar A. Current ultrafiltration techniques before, during and after pediatric cardiopulmonary bypass procedures. Perfusion. 2012; 27: 438-446 Crossref PubMed Scopus (40) Google Scholar Naik et al. postulated it may permit blood-free cardiac surgery. 11 Naik SK Knight A Elliott M. A prospective randomized study of a modified technique of ultrafiltration during pediatric open-heart surgery. Circulation. 1991; 84 (III422-31) PubMed Google Scholar Blood is typically removed from the arterial cannula and returned through the venous cannula. Others employ a modified technique in which blood is removed from the right atrium and infused into the aorta, potentially reducing concerns about cerebral shunting. 12 Myers GJ Leadon RB Mitchell LB et al. Simple modified ultrafiltration. Perfusion. 2000; 15: 447-452 Crossref PubMed Scopus (16) Google Scholar

Acetaminophen pharmacokinetics in infants and children with congenital heart disease.

Acetaminophen is routinely used for perioperative analgesia in children undergoing major surgical procedures. There are few estimates of acetaminophen pharmacokinetic parameters in children with congenital heart disease, especially those with cyanotic heart disease. The current study prospectively investigated differences in acetaminophen pharmacokinetics following surgery using cardiopulmonary bypass in children with cyanotic and acyanotic congenital heart disease. Children (2-6 years, 9-23 kg) presenting for median sternotomy for Fontan palliation (cyanotic patients) or two ventricle surgical repair (acyanotic patients) were eligible for inclusion. A single intravenous dose of acetaminophen (15 mg/kg) was administered at the start of sternal closure after separation from cardiopulmonary bypass. The time-course of acetaminophen concentrations were described using non-linear mixed effects models. One and two-compartment disposition models with first-order elimination were tested. Pharmacokinetic parameter estimates were scaled using allometry and standardized to a 70 kg person. There were 208 acetaminophen concentrations assayed from 30 children, 15 with cyanotic, and 15 with acyanotic heart disease. A 2-compartment model best described acetaminophen PK. Parameter estimates (population parameter variability, PPV%; 95% confidence interval, CI) were clearance CL 15.3L.h-1.70 kg-1 (22.2%; 13.8-16.7), intercompartment clearance Q 45.4L.h-1.70 kg-1 (22.4%; 25.2-61.9), central volume of distribution V1 33.5L.70 kg-1 (23.2%; 25.9-38.8), peripheral volume of distribution V2 32.1L.70 kg-1 (21.7%; 25.9-38.8). Neither clearance nor volume parameters differed between cyanotic and acyanotic patients. Acetaminophen pharmacokinetics were characterized using a 2-compartment model with first-order elimination following cardiac bypass surgery in children. Population pharmacokinetic parameter estimates were similar to other studies in children. No differences were detected between patients with cyanotic and acyanotic heart disease.

Sonoclot® predicts operation time and blood loss after cardiopulmonary bypass in children

BackgroundAs the circulating blood volume is relatively small in pediatric patients, blood components are quickly lost when bleeding, which make it more difficult to stop the bleeding. Particularly in pediatric cardiac surgery, loss of clotting factors associated with cardiopulmonary bypass (CPB) would likely to be prominent. As a result, bleeding is further promoted and the operation time is extended. In order to search for the relation between clotting factors and the amount of bleeding, we used a viscoelastic point of care test. ObjectivesWe used Sonoclot® as viscoelastic point of care test to evaluate coagulation function before CPB and before weaning from CPB in pediatric cardiac surgery. DesignRetrospective. SettingSingle-institutional. ParticipantsWe included 55 pediatric patients (median age 13 months [IQR 5–32]) who underwent cardiac surgery under CPB from December 2015 to November 2016. InterventionsNone. Measurements and main resultsSonoclot® analysis was performed after induction of anesthesia (pre-data, or baseline data) and before any heparinized saline was given, and right after modified ultrafiltration after weaning from CPB (post-data). Post-data was compared with post-CPB operation time and post-CPB blood loss by multiple regression analysis. Furthermore, effects of fresh frozen plasma (FFP) added on CPB on coagulation function and post-platelet function (describe as PFSC) was assessed. Activated coagulation time (describe as ACTSC) and clot rate (describe as CRSC) showed no significant change between baseline data and post-data. Post-PFSC was worsened by prolonged CPB time (p < 0.05) and correlated to bleeding amount and operation time after CPB (p < 0.05). Total amount of platelet concentrate (PC) transfused was higher in patients with smaller PFSC (p < 0.05). Total amount of FFP and PC transfused correlated with bleeding amount and operation time after CPB (p < 0.05). In the subgroup analysis, PFSC declined in the FFP-included group, whereas there was no significant difference in coagulation function. Addition of FFP to CPB did not significantly affect CR, whereas PFSC deteriorated as CPB time was prolonged (CPB time = 1/(0.0021∗PFSC + 0.0055)). ConclusionSonoclot® is useful to evaluate coagulation function in pediatric patients who undergo CPB. Preventive administration of FFP or PC in CPB circuit could reduce bleeding after CPB.

Weighted gene co-expression identification of CDKN1A as a hub inflammation gene following cardiopulmonary bypass in children with congenital heart disease.

BackgroundCongenital heart disease (CHD) is the most common type of birth defect. Most patients with CHD require surgery, and cardiopulmonary bypass (CPB) is the most common surgery performed.MethodsThe present study utilized weighted gene co-expression network analysis (WGCNA) to identify key inflammation genes after CPB for CHD. The GSE132176 dataset was downloaded from the Gene Expression Omnibus(GEO) database for WGCNA to identify the modules closely related to clinical traits. Disease enrichment, functional annotation and pathway enrichment were performed on genes in the module closely related to clinical traits using Enrichr and Metascape. Immune infiltration analysis was also performed on the training dataset using CIBERSORT. Finally, we identified hub genes using high gene significance (GS), high module members (MMs) and Cytoscape, and we verified the hub genes using an independent dataset and Western blot analysis.ResultsWGCNA showed that the brown module with 461 genes had the highest correlation to CHD after CPB. Functional annotation and pathway enrichment analysis were performed using Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses, which showed that genes in the brown module were enriched in inflammation-related pathways. In the disease enrichment analysis, genes in the brown module were enriched for inflammatory diseases. After the 30 most highly associated brown intramodular genes were screened, a protein-protein interaction network was constructed using the STRING online analysis website. The protein-protein interaction results were then calculated using 12 algorithms in the cytoHubba plugin of Cytoscape software. The final result showed that CDKN1A was the fundamental gene of post-CPB for CHD. Using another independent validation dataset (GSE12486), we confirmed that CDKN1A was significantly differentially expressed between preoperative and postoperative CPB (Wilcoxon, P = 0.0079; T-test, P = 0.006). In addition, CDKN1A expression was elevated in eosinophils, neutrophils, memory CD4 T cells and activated mast cells. Western blot analysis showed that the expression of CDKN1A protein was significantly higher postoperative CPB than preoperative CPB. Moreover, CDKN1A was mainly related to inflammation.ConclusionIn summary, we found a relationship between CDKN1A and inflammation after CPB for congenital heart disease by WGCNA, experiments and various bioinformatics methods. Thus, CDKN1A maybe serve as a biomarker or therapeutic target for accurate diagnosis and treatment of inflammation after CPB in the future.

UNGAL Predictive Value for Serum Creatinine Decrease in Critically Ill Children.

Acute kidney injury (AKI) occurs frequently in critically ill children, having an incidence of up to 26.9% and is associated with high morbidity and mortality in pediatric intensive care units (PICU). Currently, the decrease in the glomerular filtration rate is calculated using the serum creatinine levels. Nevertheless, there may be a 48 h delay between the renal injury and measurable increase in creatinine. Urinary neutrophil gelatinase-associated lipocalin (uNGAL) has been validated in relation to cardiopulmonary bypass in children, being able to detect AKI before the functional change proven by the rise in serum creatinine. Our aim was to study the utility of using uNGAL in the management of critical pediatric patients admitted to our hospital in a six month period, more specifically, its capacity to predict AKI development, alone and in the association with the renal angina index (RAI). Twenty-eight critically ill children aged from 1 day to 15 years have been included. We found that an increase in uNGAL in day 1 of admission in the PICU was significantly correlated with a decrease in creatinine clearance but not anymore in day 3. However, in our sample uNGAL did not show a significant predictability for AKI development nor the supplementary incorporation of RAI into the prediction model. Therefore, apart from cardiac surgery, the efficacy and utility or uNGAL in the management of critically ill children is still questionable. For the best prediction, we will need to incorporate not only the RAI or other PICU scores, but other biomarkers such as KIM-1, urinary cystatin, and IL 18 in larger samples.

A systematic review of clinical study evidence for pulmonary vasodilator therapy following surgery with cardiopulmonary bypass in children with CHD.

Complications from pulmonary hypertension are one of the leading contributors to morbidity and mortality post-cardiopulmonary bypass surgery in children with CHD. Pulmonary vasodilator therapies are commonly used post-operatively, but the optimal target patient population, therapy choice, timing of therapy initiation, and duration of therapy are not well defined. We used PubMed and EMBASE to identify studies from 2000 to 2020 investigating the use of pulmonary vasodilator therapy post-cardiopulmonary bypass in children aged 0-18 years. To ensure eligibility criteria, studies were systematically reviewed by two independent reviewers. We identified 26 studies of 42,971 children across four medication classes; 23 were single centre, 14 were prospective, and 11 involved randomisation (four of which employed a placebo-control arm). A disproportionate number of children were from a single retrospective study of 41,872 patients. Definitions varied, but change in pulmonary haemodynamics was the most common primary outcome, used in 14 studies. Six studies had clinical endpoints, with mortality the primary endpoint for two studies. Treatment with inhaled nitric oxide, iloprost, and sildenafil all resulted in improved haemodynamics in specific cohorts of children with post-operative pulmonary hypertension, although improved outcomes were not consistently demonstrated across all treated children. Iloprost may be a cheaper alternative to inhaled nitric oxide with similar haemodynamic response. Studies were predominantly single-centre, a control arm was rarely used in randomised studies, and haemodynamic endpoints varied significantly. Further research is needed to reduce post-operative morbidity and mortality from pulmonary hypertension in children with CHD.

Delayed concentration effect models for dabigatran anticoagulation.

IntroductionDabigatran is an anticoagulant with potential use during cardiopulmonary bypass in children and adults. The pharmacokinetic–pharmacodynamic relationship for dabigatran anticoagulation effect was investigated in an intact animal model using rabbits.MethodsTen male New Zealand white rabbits were given a novel preparation of intravenous dabigatran 15 mg.kg−1. Blood samples were collected for activated clotting time, thromboelastometric reaction time, and drug assay at 5, 15, 30, 60, 120, 180, 300, and 420 min. Plasma dabigatran concentrations and coagulation measures were analyzed using an integrated pharmacokinetic–pharmacodynamic model using nonlinear mixed effects. Effects (activated clotting and thromboelastometric reaction times) were described using a sigmoidal EMAX model. Pharmacokinetic parameters were scaled using allometry and standardized to a 70 kg size standard. Pharmacodynamics were investigated using both an effect compartment model and an indirect response (turnover) model.ResultsA two‐compartment model described dabigatran pharmacokinetics with a clearance (CL 0.135 L.min−1.70 kg−1), intercompartment clearance (Q 0.33 L.min−1.70 kg−1), central volume of distribution (V1 12.3 L.70 kg−1), and peripheral volume of distribution (V2 30.1 L.70 kg−1). The effect compartment model estimates for a sigmoid EMAX model with activated clotting time had an effect site concentration (Ce50 20.1 mg.L−1) eliciting half of the maximal effect (EMAX 899 s) and a Hill coefficient (N 0.66). The equilibration half time (T1/2keo) was 1.4 min. Results for the reaction time were plasma concentration (Cp50 65.3 mg.L−1), EMAX 34 min, N 0.80 with a baseline thromboelastometric reaction time of 0.4 min. The equilibration half time (T1/2keo) was 2.04 min.ConclusionsDabigatran reversibly binds to the active site on the thrombin molecule, preventing thrombin‐mediated activation of coagulation factors. The effect compartment model performed slightly better than the turnover model and was able to adequately capture pharmacodynamics for both activated clotting and thromboelastometric reaction times. The equilibration half time was short (<2 min). These data can be used to inform future animal preclinical studies for those undergoing cardiopulmonary bypass. These preclinical data also demonstrate the magnitude of parameter values for a delayed effect compartment model that are applicable to humans.

Prospective Assessment of Coronary Artery Flows Before and After Cardiopulmonary Bypass in Children With a Spectrum of Congenital Heart Disease.

Normative data for the effect of cardiopulmonary bypass (CPB) on coronary artery Doppler velocities by transesophageal echocardiography in paediatric patients with congenital heart disease (CHD) are lacking. The objective of the study was to prospectively examine the effects of CPB on coronary artery flow patterns by transesophageal echocardiography before and after CPB in children with CHD. All cases undergoing CHD surgery at the Hospital for Sick Children, Toronto, were eligible. The excluded cases included Norwood operation, heart transplantation, or weight <2.5 kg. Coronary Dopplers and coronary flow reserve (CFR) for the right coronary artery (RCA) and left anterior descending (LAD) were obtained. Multivariable analyses using linear regression models were performed, adjusted for age and cross-clamp time. From May 2017 to June 2018, 69 children (median age at surgery: 0.7 years, interquartile range [IQR]: 0.4-3.7 years; median weight: 7.4 kg, IQR: 5.8-13.3 kg) were included. They were grouped into shunt lesions (N= 26), obstructive lesions (N= 26), transposition of the great arteries (N= 5), and single ventricle (N= 12). N= 39 (57%) were primary repairs, and 56 (81%) had 1 CPB run. For RCA and LAD peak velocities, there was an increase from pre- to post-CPB in RCA peak 39 cm/s (IQR: 30-54 cm/s) to 65 cm/s (IQR: 47-81 cm/s), P< 0.001, mean CFR 1.52 (IQR: 1.25-1.81), and LAD peak 49 cm/s (IQR: 39-60 cm/s) to 70 cm/s (IQR: 52-90 cm/s), P < 0.001, mean CFR 1.48 (IQR: 1.14-1.77). Coronary flow velocities increase from pre- to post-CPB in congenital heart lesions. CFR is consistent across all lesions but is relatively low compared with the adult population.

Pulsatile Flow During Cardiopulmonary Bypass in Children

Pulsatile perfusion has been hypothesized (going back to the inception of cardiopulmonary bypass [CPB]) to be beneficial in cardiac surgery, although clinical evidence remains discordant and controversial, with very little pediatric evidence. Many arguments are based on the provision of a (supposedly) more physiologic flow pattern. Therefore, although the topic is not new, the clinical strategy and some of the end points chosen in the excellent study by Ündar and colleagues1 in this issue of The Annals of Thoracic Surgery certainly are.

Protective continuous ventilation strategy during cardiopulmonary bypass in children undergoing surgery for congenital heart disease: a prospective study

OBJECTIVESThe aim of this study was to evaluate if a ‘protective’ (low-tidal/low-frequency) ventilation strategy can shorten the postoperative ventilation time and minimize acute lung injury in children with congenital heart disease (CHD) undergoing repair with cardiopulmonary bypass (CPB).METHODSThis is a single-centre prospective, interventional study, including children with CHD under the age of 5 years, undergoing open-heart surgery with a CPB >60 min, in hypothermia, haemodynamically stable, and without evident genetic abnormalities. Assist-control ventilation (tidal volume of 4 ml/kg, 10 breaths/min, positive end-expiratory pressure 5 cmH2O and FiO2 0.21) was applied in a cohort of patients during CPB. We compared clinical outcomes and in fully ventilated versus non-ventilated (control) patients. Propensity score was used to weigh ventilated and control groups to correct for the effect of other confounding clinical variables. Clinical and ventilation parameters and lung inflammatory biomarkers in tracheal aspirates were measured. The primary outcome was the postoperative intubation time of more or less than 48 h.RESULTSWe included 140 children (53 ventilated, 87 non-ventilated) with different CHD. There were no deaths or adverse events in ventilated patients. Using a weighted generalized linear model, we found no sufficient evidence for an effect of intraoperative ventilation on postoperative intubation time [estimate 0.13 (95% confidence interval, –0.08; 0.35), P = 0.22].CONCLUSIONSContinuous low-tidal/low-frequency mechanical ventilation during CPB is safe and harmless. However, no significant advantages were found when compared to non-ventilated patients in terms of postoperative ventilation time.

Absorbable sutures for cardiopulmonary bypass purse strings in pediatric heart surgery

Absorbable sutures, commonly used in general surgery, are not routinely used as purse strings for arterial and venous cannulation for cardiopulmonary bypass in pediatric heart surgery.The general concern is absorbable sutures could predispose to immediate postoperative bleeding; this safety concern has been evaluated in this retrospective study. A single center, retrospective study, was conducted with criteria for inclusion patient <18 years of age, operation on with cardiopulmonary bypass for heart surgery from July 1, 2018 to June 30, 2020, with purse strings for cannulation performed with absorbable sutures. Data collection included demographics at the time of surgery, site of arterial and venous cannulation with absorbable purse strings, bleeding, required reoperation, related hospital mortality, and complications. One hundred and ninety-eight patients, mean ± standard deviation(SD) age of 1597 ± 3021 days, mean ± SDbody weight of 15.9 ± 18.8 kg, were operated on using absorbable sutures for purse strings for arterial and venous cannulation: No bleeding was reported, either intraoperative or in the immediate postoperative period, related to the type of sutures used for purse strings for cannulation. No hospital deaths or complications related to the type of sutures were observed. Based on the results of our analysis, we can conclude that the utilization of purse strings absorbable sutures for arterial and venous cannulation for cardio-pulmonary bypass in children is safe in relationship to the intraoperative and immediate postoperative period.No complications related to the use of absorbable sutures have been observed in a large pediatric patient population.

A systematic review of the evidence supporting post-operative antithrombotic use following cardiopulmonary bypass in children with CHD.

To determine the optimal antithrombotic agent choice, timing of initiation, dosing and duration of therapy for paediatric patients undergoing cardiac surgery with cardiopulmonary bypass. We used PubMed and EMBASE to systematically review the existing literature of clinical trials involving antithrombotics following cardiac surgery from 2000 to 2020 in children 0-18 years. Studies were assessed by two reviewers to ensure they met eligibility criteria. We identified 10 studies in 1929 children across three medications classes: vitamin K antagonists, cyclooxygenase inhibitors and indirect thrombin inhibitors. Four studies were retrospective, five were prospective observational cohorts (one of which used historical controls) and one was a prospective, randomised, placebo-controlled, double-blind trial. All included were single-centre studies. Eight studies used surrogate biomarkers and two used clinical endpoints as the primary endpoint. There was substantive variability in response to antithrombotics in the immediate post-operative period. Studies of warfarin and aspirin showed that laboratory monitoring levels were frequently out of therapeutic range (variably defined), and findings were mixed on the association of these derangements with bleeding or thrombotic events. Heparin was found to be safe at low doses, but breakthrough thromboembolic events were common. There are few paediatric prospective randomised clinical trials evaluating antithrombotic therapeutics post-cardiac surgery; most studies have been observational and seldom employed clinical endpoints. Standardised, validated endpoints and pragmatic trial designs may allow investigators to determine the optimal drug, timing of initiation, dosing and duration to improve outcomes by limiting post-operative morbidity and mortality related to bleeding or thrombotic events.

The result of using Steriod during cardiopulmonary bypass in children undergoing cardiac surgery

The results of steroid in pediatric after cardiac surgery with steroid during extracorporeal circulation.&#x0D; Objectives: Evaluating the clinical and laboratory characteristics in pediatric patients after cardiac surgery using steroid. Methods: A prospective, randomized, controlled clinical trial on 106 pediatric patients who underwent surgery requiring cardiopulmonary bypass at Hanoi Heart Hospital. Results: The rate of postoperative infection of the group using corticosteroids was 85.5%, the group not using corticosteroids was 96%. The rate of fever after surgery of the group using corticosteroids was 32.7%, the group not using corticosteroids was 35.3%. Troponin T concentration of group using corticosteroids was 1729.3 ± 1874.8 ng/L, group not using corticosteroids was 1855.0 ± 2658.0 ng/L. The time of mechanical ventilation and the time of recovery of the group using corticosteroids was 19.7 ± 23.6 hours and 61.8 ± &#x0D; 53.0 hours, the group not using corticosteroids was 19.8 ± 25.0 hours and 52 ,5 ± 39.1 hours. Conclusion: High-dose corticosteroids in this research did not cause adverse effects as mentioned in some studies, but did not bring any significant benefit to pediatric patients after cardiac surgery.

Methylprednisolone in Pediatric Cardiac Surgery: Is There Enough Evidence?

Corticosteroids have been used to decrease the inflammatory response to cardiac surgery and cardiopulmonary bypass in children for decades. Sparse information is present concerning the pharmacokinetics and pharmacodynamics of corticosteroids in the context of pediatric cardiac surgery. There is large interindividual variability in plasma concentrations, with indications for a larger volume of distribution in neonates compared to other age groups. There is ample evidence that perioperative use of MP leads to a decrease in pro-inflammatory mediators and an increase in anti-inflammatory mediators, with no difference in effect between doses of 2 and 30 mg/kg. No differences in inflammatory mediators have been shown between different times of administration relative to the start of surgery in various studies. MP has been shown to have a beneficial effect in certain subgroups of patients but is also associated with side effects. In lower risk categories, the balance between risk and benefit may be shifted toward risk. There is limited information on short- to medium-term outcome (mortality, low cardiac output syndrome, duration of mechanical ventilation, length of stay in the intensive care unit or the hospital), mostly from underpowered studies. No information on long-term outcome, such as neurodevelopmental outcome, is available. MP may provide a small benefit that is easily abolished by patient characteristics, surgical techniques, and perfusion management. The lack of evidence leads to large differences in practice between and within countries, and even within hospitals, so there is a need for adequately powered randomized studies.

Outcomes of extracorporeal membrane oxygenation and cardiopulmonary bypass in children after drowning-related resuscitation.

Drowning is one of the leading causes of accidental deaths in children worldwide. However, the use of long-term extracorporeal life support (ECLS) in this setting is not widely established, and rewarming is often achieved by short-term cardiopulmonary bypass (CPB) treatment. Thus, we sought to add our experience with this means of support as a bridge-to-recovery or to-decision. This retrospective single-center study analyzes the outcome of 11 children (median 23 months, minimum-maximum 3 months-6.5 years) who experienced drowning and subsequent cardiopulmonary resuscitation (CPR) between 2005 and 2016 and who were supported by veno-arterial extracorporeal membrane oxygenation (ECMO), CPB, or first CPB then ECMO. All but one incident took place in sweet water. Submersion time ranged between 10 and 50 minutes (median 23 minutes), water temperature between 2°C and 28°C (median 14°C), and body core temperature upon arrival in the emergency department between 20°C and 34°C (median 25°C). Nine patients underwent ongoing CPR from the scene until ECMO or CPB initiation in the operating room. The duration of ECMO or CPB before successful weaning/therapy withdrawal ranged between 2 and 322 hours (median 19 hours). A total of four patients (36%) survived neurologically mildly or not affected after 4 years of follow-up. The data indicate that survival is likely related to a shorter submersion time and lower water temperature. Resuscitation of pediatric patients after drowning has a poor outcome. However, ECMO or CPB might promote recovery in selected cases or serve as a bridge-to-decision tool.