Cardiopulmonary Bypass In Children Research Articles

Comparison of S100B and NSE Between Cardiac Surgery and Interventional Therapy for Children

This study aimed to compare the release of S100B and NSE between cardiac surgery and interventional therapy for children and to investigate whether S100B serum concentration correlates with cardiopulmonary bypass in children. For this study, 40 children with congenital heart disease were selected and assigned to two groups: group A (20 children undergoing surgical therapy) and group B (20 children undergoing interventional therapy). In group A, blood samples were drawn 10 min after the induction of anesthesia, immediately after aortic cross-clamping, immediately at the end of cardiopulmonary bypass (CPB), immediately at the end of the operation, then 6 and 24 h after the operation. In group B, blood samples were drawn 10 min after the induction of anesthesia, immediately at the end of the procedure, then 6 and 24 h after the procedure. In group A, S100B plasma levels during the perioperative period and 6 h after the operation were higher than the preoperative level (p < 0.05). The NSE plasma concentrations at the termination of CPB and postoperatively were higher than the preoperative level (p < 0.05). Significant correlation was found between the peak value of S100B at the termination of CPB and the durations of both CPB and aortic cross-clamping. In group B, the differences in S100B and NSE between the post- and preoperative levels were not statistically significant (p > 0.05). The perioperative cerebral impairment indirectly evaluated by the release of NSE and S100B protein is greater in children undergoing CPB than in children undergoing interventional therapy. The release of S100B had a strong correlation with the durations of CPB and aortic cross-clamping in children.

Transesophageal echocardiography-guided hybrid therapy for ventricular septal defects in children

To evaluate transesophageal echocardiography (TEE)-guided periventricular device closure for treatment of ventricular septal defects (VSD) in children. The Amplatzer device was applied, the size of which was 1 or 2 mm larger than the VSD size assessed by TEE. Via a small lower sternotomy, the device was introduced through right ventricular surface to close the VSD under continuous TEE guidance without cardiopulmonary bypass. The procedures were successful in 6 cases, including 4 cases with muscular VSD and 2 cases with perimembranous VSD. The diameter of VSD was 3 mm to 10 mm and one case had pulmonary hypertension. One case of multi-muscular VSD with transposition of the great arteries failed to the treatment because the mitral open was interfered by the device. One case had bundle branch block in ICU stay and returned to normal without special therapy. The average operation time was 30 min and blood loss was 5 approximately 20 ml, no patients required blood transfusion; the average length of ICU stay was 24 h. Patients were discharged 1 to 2 d postoperatively. At a median follow-up for 12 months, all patients were asymptomatic and had no residual ventricular shunts. With the guide of TEE, intra-operative hybrid therapy is a safe and effective method for closure of muscular and perimembranous VSD without cardiopulmonary bypass in children.

Procalcitonin versus C-reactive protein and immature-to-total neutrophil ratio as markers of infection after cardiopulmonary bypass in children

To document concentrations of procalcitonin (PCT), C-reactive protein (CRP), and immature-to-total neutrophil ratio (ITR), postcardiopulmonary bypass (CPB), and to test the hypothesis that PCT is a more reliable marker of infection than CRP or ITR in the post-CPB child. Prospective cohort study. Pediatric intensive care units at Royal Children's Hospital, Melbourne, Australia and Birmingham Children's Hospital, UK. First stage: 283 post-CPB children; second stage: 65 post-CPB children with suspected infection. In the first stage, PCT, ITR, and CRP were measured serially on the first, second, third, and fifth postoperative day (POD). In the second stage, PCT, ITR, and CRP were measured in the specimens taken in the period before and after the clinical diagnosis of infection. In children without infection, the median peak PCT concentration more than 5 PODs was 1.0 ng/mL, in children with local infection 1.0 ng/mL, and in children with definite sepsis 14.8 ng/mL. CRP increased in all subgroups of children studied, reaching a peak on POD 3 (median 51 mg/L). In definite sepsis, CRP was increased more than the other subgroups. ITR remained high with a median of 0.08 from POD 1 and gradually decreased, except in definite sepsis, where it remained high. In a receiver operating characteristic curve analysis, PCT was the most reliable variable for the diagnosis of probable/definite sepsis with area under the curve 0.84 (95% confidence interval, 0.75-0.92) compared with 0.73 (0.62-0.84) for ITR and 0.62 (0.52-0.73) for CRP. CRP was a poor marker of sepsis in this study. Children with a PCT <2.2 ng/mL or ITR <0.08 were unlikely to have definite or probable sepsis. However, only a third of children with high values of PCT and ITR had definite or probable sepsis.

Improving function following cardiopulmonary bypass in children: Digging deeper than steroids*

Improving function following cardiopulmonary bypass in children: Digging deeper than steroids*

Copper and Ceruloplasmin in Children Undergoing Heart Surgery with Cardiopulmonary Bypass

Heart surgery with cardiopulmonary bypass (CPB) nowadays has become a routine procedure. However, under nonadequate hemodynamic conditions and because of the changes related to ischemia-reperfusion, there is a possibility to provoke oxidative stress with all undesirable consequences. Copper (Cu) is closely related to this stress, taking part in the formation of the hazardous-free radicals. Meanwhile, at least in the pediatric area, little is known about Cu kinetics during cardiac surgery. The purpose of the present work was to study Cu and ceruloplasmin (Cp) dynamics during surgery with CPB in children. Twenty-one patients of both genders from Campo Grande, Brazil with congenital heart conditions were enrolled in the investigation. Blood samples were collected before the surgery and during and 24 h after it. Cu and Cp levels were measured at selected moments and the influence of hemodilution studied. It was concluded that serum Cu dynamics during cardiopulmonary bypass reflects the protective effects of this trace element. Ceruloplasmin levels correlate positively with copper.

The use of hormonal therapy in pediatric heart disease

The endocrine system plays an intricate role in the regulation and modulation of cardiovascular function. Several hormones including thyroid, mineralocorticoid, glucocorticoid, arginine-vasopressin (AVP), and growth hormone (GH) have been investigated as adjunctive therapies in pediatric cardiac disease. Thyroid hormone supplementation appears to be safe in neonatal and pediatric post-operative cardiac patients, but the benefits have been modest and inconsistent. Glucocorticoids appear to decrease the inflammatory response associated with cardiopulmonary bypass in children, but have little effect on clinical outcomes. The role of AVP in pediatric shock remains limited due to inconsistent trial results and its potential side effect profile. Although mineralcorticoids are commonly used to treat neurocardiogenic syncope, little to no benefit has been demonstrated in controlled trials. GH normalizes altered cardiac function in children who are GH deficient, but its effectiveness in the treatment of heart failure has been variable. Overall, the use of these hormones in a variety of pediatric cardiac conditions generally appears to be safe, but their efficacy for relieving symptoms, improving cardiac function, and improving clinical outcomes remains unclear.

Abstract 2595: Cardiopulmonary Bypass Does Not Cause Neurocognitive Decline in Children and Adolescents Undergoing Repair of Acyanotic Congenital Heart Disease

Background: Previous studies describing the neurocognitive (neuro) effects of cardiopulmonary bypass (CPB) have been performed following surgery in infancy for complex congenital heart disease (CHD) and in adults with acquired heart disease. These patients (pts) have many causes for adverse neuro outcomes with conflicting results regarding the contribution of CPB. The impact of CPB in children with less complex CHD is unknown. We sought to describe the effects of CPB on neuro function in children following repair of acyanotic CHD. Methods: We performed a prospective cohort study of pts 5–18 yrs of age undergoing primary repair of CHD. Neuro testing battery included assessment of intellectual function (IQ), memory, motor skills, attention, executive function, and an evaluation by a pediatric neurologist pre- and 6 months post-CPB. Non-CPB effects of surgery were assessed by similarly testing pts undergoing repair of pectus excavatum (non-CPB). Practice effects of serial testing were controlled by enrolling non-surgical pts (mild CHD) and creating a reliability-stability index to adjust surgical group scores. Anxiety was assessed as a covariate. Results: CPB pts ( n =41) included repair of atrial [17] or ventricular [6] septal defect, coronary anomaly [8], aortic valve [5] or other [5]. Control pts included pectus repair ( n =20) and non-surgical CHD pts ( n =16). Groups were similar in age, gender, race, socioeconomic status and baseline scores. Neurological exams before and after surgery were not different between groups. Controlling for the effects of serial testing, there were no significant (p&lt;.05) changes in the mean scores of either surgical group in areas of IQ, memory, motor skills, attention, or executive function. In addition, there were no differences in the percentage of patients in either surgical group that had a significant (&gt;1 SD) decline in scores after surgery. Conclusions : When controlling for the non-CPB effects of surgery (hospitalization, anxiety, etc.) and the practice effects of serial testing, there were no independent effects of CPB on neuro status 6 months after repair of acyanotic CHD. We believe that the potential neuro sequelae of CPB should not be a major factor in the decision to recommend CHD surgery in otherwise healthy children.

Plasma angiopoietin-2 levels increase in children following cardiopulmonary bypass.

The aim was to investigate the effects of cardiopulmonary bypass (CPB) on plasma levels of the vascular growth factors, angiopoietin (angpt)-1, angpt-2, and vascular endothelial growth factor (VEGF). The design was a prospective, clinical investigation. The setting was a 12-bed pediatric cardiac intensive care unit of a tertiary children's medical center. The patients were 48 children (median age, 5 months) undergoing surgical correction or palliation of congenital heart disease who were prospectively enrolled following informed consent. There were no interventions in this study. Plasma samples were obtained at baseline and at 0, 6, and 24 h following CPB. Angpt-1, angpt-2, and VEGF levels were measured via commercial ELISA. Angpt-2 levels increased by 6 h (0.95, IQR 0.43-2.08 ng mL(-1) vs. 4.62, IQR 1.16-6.93 ng mL(-1), P < 0.05) and remained significantly elevated at 24 h after CPB (1.85, IQR 0.70-2.76 ng mL(-1); P < 0.05). Angpt-1 levels remained unchanged immediately after CPB, but were significantly decreased at 24 h after CPB (0.64, IQR 0.40-1.62 ng mL(-1) vs. 1.99, IQR 1.23-2.63 ng mL(-1), P < 0.05). Angpt-2 levels correlated significantly with cardiac intensive care unit (CICU) length of stay (LOS) and were an independent predictor for CICU LOS on subsequent multivariate analysis. Angpt-2 appears to be an important biomarker of adverse outcome following CPB in children.

Abstract 2353: Angiopoietin Expression in Children Following Cardiopulmonary Bypass

Introduction: Capillary leak syndrome (CLS) is a serious, potentially life-threatening problem in children with congenital heart disease (CHD) that is partly related to the host inflammatory response following cardiopulmonary bypass (CPB). The angiopoietins are a family of vascular growth factors that are necessary for angiogenesis. Two members of the angiopoietin family are well characterized in humans - angiopoietin-1 (angpt-1) and angpt-2 - both of which appear to act on the Tie2 receptor, found primarily on vascular endothelial cells. Angpt-1 protects against capillary leak, while angpt-2 promotes increased vascular permeability and potentiates inflammation. Hypothesis: We hypothesized that plasma angpt-2 levels increase following CPB and correlate with indices of systemic inflammation and capillary leak. Methods: Plasma samples were obtained at baseline and at 0, 4, and 24 h after CPB in 49 children (median age 5 mo) with CHD. Troponin-I, angpt-1, angpt-2, VEGF, and soluble Tie2 (sTie2) were measured via a commercially available ELISA. Cytokines were measured using a multiplex cytokine assay. Results: CPB (mean CPB 119 min, cross-clamp, 71 mins) increased troponin-I, IL-6, IL-8, and IL-10 expression. Plasma angpt-2 levels increased by 6 h (952 pg/mL vs 462 pg/mL, p&lt;0.05) and remained significantly elevated at 24 h after CPB (1850 pg/mL, p&lt;0.05). Plasma angpt-1 levels remained unchanged immediately after CPB, but were significantly decreased at 24 h after CPB (635 pg/mL vs 991 pg/mL, p&lt;0.05). Similarly, plasma sTie2 levels increased after CPB (6.4 ng/mL vs 2.86 ng/mL, p&lt;0.05) before returning to baseline by 6 h after CPB. Plasma VEGF levels were not different at any timepoint. Plasma angpt-2 levels after CPB signficantly correlated with troponin-I, IL-6, IL-8, and IL-10 levels. There was a significant correlation between plasma angpt-2 levels and CPB time. Finally, higher plasma angpt-2 levels at 6 h correlated significantly with increased length of stay in the CICU (r=0.86; p&lt;0.0001). Conclusions: Angpt-2 appears to be an important biomarker of vascular endothelial injury and capillary leak following CPB in children with CHD. Further studies on the role of angpt-2 in the pathophysiology of CLS following CPB are warranted.

Effect of inhaled corticosteroid on pulmonary injury and inflammatory mediator production after cardiopulmonary bypass in children*

To determine whether inhaled steroid administration after cardiopulmonary bypass will attenuate pulmonary inflammation and improve lung compliance and oxygenation. Randomized, prospective, double-blind, placebo-controlled clinical trial. Children's Hospital of Michigan, intensive care unit. Thirty-two children <2 yrs of age with congenital heart disease requiring cardiopulmonary bypass. Participants were randomly assigned to one of two groups. Group 1 (n = 16) received an inhaled steroid, Budesonide (0.25 mg/2 mL), and group 2 (n = 16) received an inhaled placebo (2 mL of inhaled 0.9% saline). The nebulizations were given at the end of cardiopulmonary bypass, 6 hrs after cardiopulmonary bypass, and 12 hrs after cardiopulmonary bypass. Two hours after each nebulization, bronchoalveolar lavage for interleukin-6 and interleukin-8 was collected. The concentrations of interleukin-6 and interleukin-8 in the bronchoalveolar lavage increased in both groups after cardiopulmonary bypass. Interleukin-6 peaked 2 hrs after cardiopulmonary bypass and was decreasing by 14 hrs after cardiopulmonary bypass. However, administration of corticosteroid did not affect the production of interleukin-6 when compared with the placebo group (378 +/- 728 vs. 287 +/- 583 pg/mL pre-cardiopulmonary bypass, 1662 +/- 1410 vs. 1584 +/- 1645 pg/mL at the end of cardiopulmonary bypass, 2601 +/- 3132 vs. 3677 +/- 4935 pg/mL 2 hrs after cardiopulmonary bypass, and 1792 +/- 3100 vs. 1283 +/- 1344 pg/mL 14 hrs after cardiopulmonary bypass; p > .05). Likewise, interleukin-8 in the lavage fluid was similar in both the placebo and steroid groups at all time points (570 +/- 764 vs. 990 +/- 1147 pg/mL pre-cardiopulmonary bypass, 1647 +/- 1232 vs. 1394 +/- 1079 pg/mL at the end of cardiopulmonary bypass, 1581 +/- 802 vs. 1523 +/- 852 pg/mL 2 hrs after cardiopulmonary bypass, and 1652 +/- 1069 pg/mL vs. 1808 +/- 281 pg/mL 14 hrs after cardiopulmonary bypass; p > .05). Lung compliance and oxygenation were similar in both groups. Cardiopulmonary bypass is associated with a pulmonary inflammatory response. Inhaled corticosteroid did not affect the pulmonary inflammatory response as measured by interleukin-6 and interleukin-8 concentrations in the lung lavage after cardiopulmonary bypass. Pulmonary mechanics and oxygenation were not improved by the use of inhaled corticosteroid.

Effects of cardiopulmonary bypass circuit reduction and residual volume salvage on allogeneic transfusion requirements in infants undergoing cardiac surgery

Cardiopulmonary bypass in children may cause severe hemodilution and can lead to excessive perioperative blood loss and high transfusion requirements. Minimization of cardiopulmonary bypass circuit and salvage of red blood cells from the residual volume after the procedure are widely utilized to reduce allogeneic transfusion. We evaluated the effectiveness of those measures introduced in infant cardiac surgery in our institution. This retrospective observational study included 148 consecutive infants between 1 and 12 months of age, with a body weight <10 kg, who underwent an elective cardiac operation between 1997 and 2005. Patients were divided into three groups defined by the circuit prime volume; 700 ml (Group 1), 450 ml (Group 2) and 330 ml (Group 3). In Group 1 residual volume after perfusion was discarded and in Groups 2 and 3 was processed in a cell saving device. Analyzed variables were: perioperative blood loss, transfusion of homologous blood products and cell salvage product, and hematology data. Reduction of the circuit volume significantly diminished use of red blood cell concentrates from 1.6 units to 0.8 units (P<0.0001), and fresh frozen plasma from 1.3 units to 0.4 units (P<0.0001). Utilization of the cell salvage product reduced significantly (P=0.023) the postoperative need for homologous blood transfusion. Therefore, both measures proved to be effective in reducing homologous blood transfusion in infant cardiac surgery.

Relationship between increased blood pressure and hematocrit during modified ultrafiltration for pediatric open heart surgery

Modified ultrafiltration increases blood pressure after cardiopulmonary bypass in children. To investigate the cause of this hemodynamic improvement, we assessed the relationship between increased blood pressure and hematocrit. We retrospectively assessed 30 consecutive patients who underwent ventricular septal defect closure, and divided them into two groups: group M (modified ultrafiltration, n=15) and group C (conventional ultra-filtration, n=15). We compared the intraoperative transitions of blood pressure and hematocrit, and analyzed the correlations between blood pressure and hematocrit at 15 min after cardiopulmonary bypass (immediately after modified ultrafiltration in group M) and between the percent increases in blood pressure and hematocrit during modified ultrafiltration. Although intraoperative central venous pressure and dopamine dosage were similar, in group M, increases in hematocrit (26.4% +/- 4.9% to 31.9% +/- 5.7%, P < 0.01) and systolic blood pressure (61.1 +/- 10.3 to 75.6 +/- 11.5 mmHg, P < 0.01) occurred during modified ultrafiltration. Furthermore, diastolic and mean blood pressure at 15 min after cardiopulmonary bypass (after modified ultrafiltration) were higher in group M than in group C. However, systolic, mean, and diastolic blood pressure were not correlated with increased hematocrit after modified ultrafiltration, and there was also no correlation between the percent increases in each blood pressure and hematocrit. Modified ultrafiltration increased blood pressure and hematocrit immediately after cardiopulmonary bypass in children. However, no correlations were detected between the increases in blood pressure and hematocrit. These results indicate hemoconcentration is not the major cause of the increased blood pressure during modified ultrafiltration.

Platelet dysfunction after normothermic cardiopulmonary bypass in children: Effect of high-dose aprotinin

Platelet dysfunction after cardiopulmonary bypass (CPB) can contribute to excessive post-operative bleeding. Most trials of the protective effect of aprotinin in this setting have involved hypothermic CPB, which is more deleterious for platelets than normothermic CPB. Here we investigated the effect of aprotinin on platelet function during normothermic CPB in pediatric patients. Twenty patients (9 newborns [<1 month old] and 11 infants [<36 month old]), weighting less than 15 kg and undergoing normothermic CPB (35-36 degrees C) were randomly assigned to two equal groups, one of which received high-dose aprotinin. Platelet function was assessed by flow cytometry just before CPB and 5 minutes after heparin neutralization. F1 + 2 fragments were measured by ELISA before and 5 minutes after CPB. Platelet activation marker expression (CD62P and activated alphaIIbbeta3) induced by ADP or TRAP was lower after CPB than before CPB, suggesting a deleterious effect of normothermic CPB on platelet function. Prothrombin fragment F1 + 2 levels increased after CPB. Aprotinin administration did not influence the level of prothrombin fragments or platelet marker expression measured in basal condition. However, after CPB, the capacity for platelet activation was higher in the aprotinin group, as shown by measuring CD62P expression after TRAP activation (p = 0.05). This study suggests that pediatric normothermic CPB causes platelet dysfunction, and that high-dose aprotinin has a protective effect.

Cerebral oxygen saturation changes during modified ultrafiltration

A number of adverse effects are associated with the use of cardiopulmonary bypass (CPB) in pediatric patients undergoing cardiac surgery. Pulmonary compliance and gas exchange are decreased, and myocardial edema may result in diastolic dysfunction. Modified ultrafiltration (MUF) after CPB in children decreases body water, removes inflammatory mediators, improves hemodynamics, and decreases transfusion requirements. To determine the factors that influence cerebral tissue oxygenation during MUF. Pediatric patients received the usual treatment, with MUF times from 10 to 19 min, as determined by circuit volume and patient hemodynamic stability. Preliminary results in five patients with arterial saturation > 95% during MUF demonstrates four predictors of cerebral oxygenation, using stepwise multiple linear regression with cerebral oxygen saturation as the dependant variable. In order of significance, they are pCO2, ultrafiltration flow rate, mean arterial pressure, and hematocrit. The results of this study will be used to determine the optimal performance of MUF. Maximizing cerebral oxygen delivery during this early post-bypass period is extremely important, and identifying the factors responsible for increased cerebral oxygen delivery during MUF allows the clinician to make the appropriate changes necessary to achieve this.

Comparison of two different extracorporeal circuits on cerebral embolization during cardiopulmonary bypass in children

To compare the effect of two different extracorporeal circuits on the counts of high-intensity transient signals (HITS) during pediatric cardiopulmonary bypass (CPB). Transcranial Doppler was used to detect HITS associated with extracorporeal sources during the period of aortic crossclamping in the middle cerebral artery of children undergoing CPB. Based on body size, children were assigned one of two extracorporeal circuits (A or B). Circuit A included a D-705 oxygenator and associated reservoir, and circuit B included a Lilliput oxygenator and reservoir. Patients were further classified into two groups according to the complexity of surgical repair: single simple lesions or multiple complex lesions. We studied 109 pediatric patients. Surgery for multiple complex lesions was associated with longer periods of aortic crossclamping and CPB (p < 0.0001). The median count of extracorporeal HITS was 12 (25th, 75th percentiles: 3, 51). The type of extracorporeal circuit (p = 0.012) and the complexity of surgical repair (p < 0.0001) had an effect on the HITS counts. The use of circuit A was associated with higher HITS counts during surgery for multiple complex lesions compared to single simple lesions (p < 0.0001). Conversely, no differences were found with the use of circuit B between these two surgical groups (p > 0.25). During surgery for multiple complex lesions, patients treated with circuit A showed higher HITS counts than those with circuit B (p < 0.01), but there were no circuit-related differences in HITS counts (p = 0.30) during single simple lesions. Variations in the design characteristics of extracorporeal circuits can increase cerebral emboli during CPB in children. This may be related to the reduced ability of some circuits to remove emboli during long periods of CPB for complex congenital heart-surgery.

Effect of Polymer Coating (Poly 2-Methoxyethylacrylate) of the Oxygenator on Hemostatic Markers During Cardiopulmonary Bypass in Children

Heparin and other oxygenator coatings have been used in attempts to reduce hemostatic activation during cardiopulmonary bypass (CPB). This study evaluated whether an oxygenator coated with poly 2-methoxyethylacrylate (PMEA) (X-coating; Terumo Corporation, Tokyo, Japan) would cause less activation of coagulation and fibrinolytic systems during CPB in children than a noncoated oxygenator. Observational study. University-affiliated children's hospital. Twenty-six patients, 3 months to 5 years old, who underwent congenital heart surgery for repair of a ventricular septal defect, atrial septal defect, or both. Patients were divided into 2 age-matched groups based on the type of oxygenator used: a noncoated oxygenator (group NC) versus a PMEA-coated oxygenator (group C). Blood samples for coagulation and fibrinolytic markers were compared before, during, and after CPB. Despite increases in thrombin generation markers (F1.2 and TAT) at certain times during CPB in group C compared to group NC, a comparison over all times during CPB were not statistically different between groups. Overall D-dimer concentrations during CPB were elevated in group C compared to group NC (p = 0.02). Active tPA and active PAI-1 were not different between groups during or after CPB. Group C had higher platelet counts (181,000 +/- 29,000) during CPB than group NC (155,000 +/- 57,000, p = 0.04) but not postoperatively. Twelve hours postoperatively, chest tube outputs were 8.8 +/- 3 mL/kg in group C and 19.1 +/- 12 mL/kg in group NC (p = 0.003). The corresponding outputs 24 hours after surgery were 12.4 +/- 3 mL/kg and 24 +/- 11 mL/kg, respectively (p = 0.005). Except for a somewhat higher platelet count during CPB, there was no indication that PMEA coating resulted in less activation of coagulation and fibrinolytic systems. The lower postoperative chest tube output observed after CPB with PMEA-coated oxygenators needs to be studied further.

Characterizing the Inflammatory Response to Cardiopulmonary Bypass in Children

Cardiopulmonary bypass is known to trigger a global inflammatory response. Age-dependent differences in the inflammatory response, the increased susceptibility to injury of immature organ systems, and the larger extracorporeal circuit to patient size ratio results in greater susceptibility of younger and smaller patients to the damaging effects of cardiopulmonary bypass. In this review the components of the inflammatory response to cardiopulmonary bypass are reviewed with special reference to the pediatric age group, including the age-specific impact on organ systems. In addition the current and evolving strategies to prevent, limit, and treat the inflammatory response to cardiopulmonary bypass in children are examined.

Transient Th1/Th2 disbalance indicates postoperative effusions and edema after cardiopulmonary bypass in children

Cardiac surgery with cardiopulmonary bypass (CPB) induces substantial release of IL-10, indicating increased Th2 cell response. Therefore, in this study, we wanted to verify if this response is due to CPB or surgical trauma, and to study its relation to postoperative effusions and edema (POEE) in children. Th1/Th2 reaction was monitored in children undergoing cardiovascular surgery with (n = 75) and without CPB (n = 29). Surgery with CPB compared to surgery without CPB induced a transient shift towards Th2. Elevated Th2 response was related to increased vascular permeability and POEE. The immune suppression/Th2 response is typical for CPB, and at intermediate level is tolerable but at high level could be adverse for the patients.

Effect of Modified Ultrafiltration on Pulmonary Function After Cardiopulmonary Bypass

Effect of Modified Ultrafiltration on Pulmonary Function After Cardiopulmonary Bypass

Protein oxidation injury occurs during pediatric cardiopulmonary bypass

Proteins are the major effectors of biological structure and function. Oxidation-induced changes to protein structure can critically impair protein function, with important pathologic consequences. This study was undertaken to examine whether oxidation-induced changes to protein structure occur during pediatric cardiopulmonary bypass and to examine the association with postoperative outcome. Elevation of the 3,4-dihydroxyphenylalanine content of a protein relative to its native tyrosine content indicates structural damage due to oxidation. Protein 3,4-dihydroxyphenylalanine/native tyrosine ratios were measured before surgery and up to 6 hours after institution of cardiopulmonary bypass in 24 children undergoing repair of congenital heart disease, who were prospectively selected to form a cyanotic and comparable acyanotic control group. Results were correlated with perioperative variables and postoperative outcomes. Elevation of protein 3,4-dihydroxyphenylalanine/tyrosine ratios above baseline (0.48 mmol/mol [SD, 0.11 mmol/mol] vs 0.36 mmol/mol [SD, 0.13 mmol/mol]; P = .001) occurred within 30 minutes of initiating cardiopulmonary bypass in cyanotic but not in acyanotic children and correlated inversely with preoperative arterial oxygen saturation (R = -0.52; P = .03). Protein 3,4-dihydroxyphenylalanine/tyrosine ratios were also increased above baseline at 120 minutes (0.44 mmol/mol [SD, 0.12 mmol/mol]; P = .007) and 180 minutes (0.40 mmol/mol [SD, 0.14 mmol/mol]; P = .01) after the institution of cardiopulmonary bypass in children who underwent prolonged procedures. Elevation of 3,4-dihydroxyphenylalanine/tyrosine during prolonged procedures was associated with postoperative arrhythmias and the need for increased inotropic support (P = .001). Oxidative injury to proteins occurs during pediatric cardiopulmonary bypass. Cyanotic children are most at risk, particularly those undergoing prolonged procedures, in whom elevation of the protein 3,4-dihydroxyphenylalanine/tyrosine ratio is associated with increased postoperative morbidity.