Novel Choices of Cannula for Blood Delivery via Femoral Artery in Pediatric Patients.

We previously presented a cardiopulmonary bypass (CPB) method with blood delivery via femoral artery cannulation for pediatric aortic arch repair operations using the Radifocus Introducer sheath. However, the flow rate with the Radifocus Introducer sheath is limited by accessory parts with the same structure having a smaller inner diameter among different sizes, rather than the sheath body. Therefore, we further devised a combination of the JELCO IV catheter, an extension tube, and a three-way stopcock with a larger opening to obtain more flow rate keeping the CPB circuit pressure significantly lower than when using the Radifocus Introducer sheath successfully.

Contemporary results of aortic valve repair for congenital disease: lessons for management and staged strategy.

OBJECTIVES: Any aortic valve (AoV) operation in children (repair, Ross or mechanical replacement) is a palliation and reinterventions are frequent. AoV repair is a temporary solution primarily aimed at allowing the patient to grow to an age when more definitive solutions are available. We retrospectively analysed AoV repair effectiveness across the whole age spectrum of children, excluding neonates and AoV disease secondary to congenital heart disease. METHODS: From 2003 to 2015, 193 consecutive patients were included. The mean age was 9.2 ± 6.9 years (22% <1 year); 86 (45%) had a preceding balloon valvuloplasty. The indications for the procedure were stenotic (n = 123; 64%), regurgitant (n = 63; 33%) or combined (n = 7; 4%) disease. The procedures performed were commissurotomy shaving (n = 74; 38%), leaflet replacement (n = 78; 40%), leaflet extension (n = 21; 11%) and neocommissure creation (n = 21; 11%). Post-repair geometry was tricuspid in 137 (71%) patients. RESULTS: The 10-year survival rate was 97.1%. Freedom from reoperation and replacement at 7 years was, respectively, 57% (95% confidence interval, 47-66) and 68% (95% confidence interval, 59-76). In multivariate analysis, balloon dilatation before 6 months, the absence of a developed commissure, a non-tricuspid post-repair geometry and cross-clamp duration were predictors for reoperation and replacement. After a mean follow-up period of 5.1 ± 3.0 years, 145 (75%) patients had a preserved native valve, with undisturbed valve function (peak gradient <40 mmHg, regurgitation ≤mild) in 113 (58%). CONCLUSIONS: Aortic valve repair in children is safe and effective in delaying the timing for more definitive solution. Surgical strategy should be individualized according to the age of the patient. Avoidance of early balloon dilatation and aiming for a tricuspid post-repair arrangement may improve outcomes.

Prolonged Activated Clotting Time after Protamine Administration Does Not Indicate Residual Heparinization after Cardiopulmonary Bypass in Pediatric Open Heart Surgery.

BACKGROUND: In open heart surgery, heparinization is commonly neutralized using an empirical heparin:protamine ratio ranging between 1:1 and 1:1.5. However, these ratios may result in protamine overdose that should be avoided for its negative side effects on the coagulation system. This study aimed to indicate the appropriate treatment for prolonged activated clotting time (ACT) after protamine administration following cardiopulmonary bypass (CPB) in pediatric open heart surgery by investigating the underlying reasons for it. METHODS: Twenty-seven children (<10 kg) undergoing open heart surgery were included. Heparin was administered only before CPB (400 IU/kg) and in the pump priming volume for CPB (2,000 IU) and was neutralized by 1:1 protamine after CPB. The blood heparin concentration was measured using anti-Xa assay. ACT and blood concentrations of heparin, coagulation factors, thrombin-antithrombin complex, and prothrombin fragment 1 + 2 were assessed. A rotational thromboelastometry (ROTEM; Tem International GmbH, München, Bayern, Germany) was used to confirm the coagulation status and residual heparin after protamine administration. RESULTS: Anti-Xa assay showed that there is no residual heparin in the blood after 1:1 protamine administration. Nevertheless, ACT (128.89 ± 3.09 seconds before heparin administration) remained prolonged (177.14 ± 5.43 seconds at 10 minutes after protamine, 182.00 ± 5.90 seconds at 30 minutes after protamine). The blood concentrations of coagulation factors were significantly lower than those before heparin administration (p < 0.01). The low FIBTEM MCF of ROTEM (4.43 ± 0.32 mm) at 10 minutes after protamine indicated low fibrinogen concentration. CONCLUSION: Prolonged ACT after heparin neutralization by 1:1 protamine administration does not necessarily indicate residual heparin, but low blood concentrations of coagulation factors should be considered as a reason as well. Accordingly, supply of coagulation factors instead of additional protamine should be considered.

Lost unilateral capillary perfusion during nonpulsatile pulmonary circulation: successful recovery by oral sildenafil.

Good status of pulmonary perfusion is essential for a successful outcome after the Fontan procedure. Increased pulmonary pressure and vascular resistance, small size of the pulmonary arteries, and significant branch stenoses reflect some of the main problems causing failing Fontan circulation. Here we report a child who underwent a staged Fontan procedure with subsequent subtotal loss of the left-sided pulmonary perfusion, although branch stenosis was successfully treated by stent implantation. Oral sildenafil caused restoration of the capillary vascular bed, improved left-sided lung perfusion, and resulted in significant clinical benefit.

Tranexamic acid: an alternative to aprotinin as antifibrinolytic therapy in pediatric congenital heart surgery.

OBJECTIVE: There has been concern about the usage of aprotinin, an antifibrinolytic drug that was often used in pediatric cardiac surgery until 2006. At our center, these concerns led to the replacement of aprotinin with tranexamic acid for antifibrinolytic treatment. METHODS: In this retrospective observational study, two groups of pediatric patients were studied during two different periods, receiving either aprotinin (n=70) or tranexamic acid (n=70) upon cardiac surgery. Data were collected from children with cyanotic heart defects, children who weighed less than 10 kg, and children who underwent re-operation. RESULTS: There was no difference in terms of blood loss or amount of erythrocyte concentrates and fresh frozen plasma transfused. Only the intraoperative amount of platelet concentrate received by children in the tranexamic acid group was 29 ml (p=0.013) higher. There was no significant difference in the length of stay at the intensive care unit, in renal function values, or in the rate of rethoracotomy. CONCLUSIONS: The results of this study suggest that tranexamic acid represents an adequate alternative to aprotinin in congenital cardiac surgery.

Influence of two perfusion strategies on oxygen metabolism in paediatric cardiac surgery. Evaluation of the high-flow, low-resistance technique.

OBJECTIVE: Paediatric cardiac surgery is often performed under hypothermic conditions, that is, with a reduced core body temperature. Certain interventions even require the circulation to be stopped. This can only be done at a body temperature of 18 degrees C, with no risk of neurological damage and harm to the brain and other organs. Vasoconstriction is a natural reaction of the body to cold, causing the blood vessels to contract. Such a reaction would lead to a clear rise in blood pressure on cardiopulmonary bypass (CPB). Since the blood pressure is regulated in the arteriolar loop of the capillary system, there is a marked increase in blood pressure and a suppression of free water into the surrounding tissue, which, in turn, may lead to the intra-operative development of oedemas. This study aimed to investigate whether the high-flow, low-resistance (HFLR) technique offers any benefits over conventional methods. METHOD: This open, prospective, randomised study was to recruit 48 children scheduled to undergo surgery for congenital heart disease. To investigate the two different perfusion strategies, we have measured intestinal perfusion as well as skin perfusion with laser Doppler spectroscopy. To identify the effects on the immune system, selected immunologic parameters of systemic inflammation were additionally measured. Laser Doppler spectroscopy is a method that uses a glass fibre probe to determine the parameters of oxygen saturation of haemoglobin and relative haemoglobin quantity in an illuminated tissue volume, as well as the perfusion parameters of relative blood flow and blood flow velocity in the sample volume of the probe. RESULTS: During the study period, the change in oxygen saturation over time was comparable in both groups. At the end of surgery, the patients of the high-flow group had significantly higher saturation levels in the intestinal mucosa (p<0.05). Over the course of intensive care, the groups did not differ in terms of fluid supply, administration of packed red blood cells, platelet concentrates or fresh frozen plasma. Analysis of urinary output revealed significant group differences. It was higher in the patients of the high-flow group than the normal-flow group (p<0.03), without differences in diuretic administration. CONCLUSION: Laser Doppler spectroscopy is highly suited to the detection even of the slightest changes in flow characteristics and oxygenation of the skin, musculature and intestinal mucosa during surgery with extracorporeal circulation using CPB. At the same time, the technique of HFLR perfusion was found to have benefits over conventional bypass methods.

Compared fate of small-diameter Contegras and homografts in the pulmonary position.

OBJECTIVE: This study analyzes whether small-diameter Contegras behave in the same way as small-diameter homografts, when implanted for the first time in pulmonary position. METHODS: Small-diameter conduits include 12 and 14 mm Contegras and 8-14 mm homografts. Graft dysfunction is defined as right ventricular outflow tract obstruction with peak echo-Doppler gradient>40 mmHg, or grade III/IV graft regurgitation. Graft failure is defined as need for conduit replacement or need for catheter or surgical reintervention. Thirty-eight patients who received small Contegras (n=25) and small homografts (n=13) from October 2002 to end December 2006 were studied. The most frequent indication was pulmonary atresia and ventricular septal defect (n=20; 10 associated with major aorto-pulmonary collateral arteries), followed by truncus arteriosus (n=12). Most patients' characteristics were comparable except that recipients of homografts were smaller (p for body area=0.014). Survival, freedom from graft dysfunction, failure and explantation were estimated by the Kaplan-Meier method. The log-rank test was used to compare outcomes. RESULTS: There were three early and four late deaths. No death was graft related. Survival was 80+/-8.2% for patients with Contegras and 77+/-11.7% for those with allografts: p=0.82. Mean follow-up duration is 22+/-16 months. Freedom from dysfunction for Contegras conduits decreased in the first 6 months and stabilized at 58+/-11% from month 14. For homografts it decreased only 1 year after implantation, down to 35+/-19.7% from month 31: p=0.61. Freedom from Contegras failure diminished the first 16 months to level out at 57+/-13%. No homograft failed the first 2 years. With a p-value of 0.14, homografts tended to fail less frequently. Five grafts were explanted. Freedom from explantation was similar (p=0.98): 90+/-6.7% for Contegras and 75+/-21.6% for homografts at year 3. CONCLUSION: In the first 4 years after pulmonary implantation of small-diameter Contegras and homografts, the fate of both conduits was statistically similar, in spite of different behavior. As Contegras is 'off-the-shelf' available, it constitutes a sound alternative to homograft for right ventricular outflow tract reconstruction in neonates and infants.

The arterial switch operation in Europe for transposition of the great arteries: a multi-institutional study from the European Congenital Heart Surgeons Association.

OBJECTIVES: This study analyzes the results of the arterial switch operation for transposition of the great arteries in member institutions of the European Congenital Heart Surgeons Association. METHODS: The records of 613 patients who underwent primary arterial switch operations in each of 19 participating institutions in the period from January 1998 through December 2000 were reviewed retrospectively. RESULTS: A ventricular septal defect was present in 186 (30%) patients. Coronary anatomy was type A in 69% of the patients, and aortic arch pathology was present in 20% of patients with ventricular septal defect. Rashkind septostomy was performed in 75% of the patients, and 69% received prostaglandin. There were 37 hospital deaths (operative mortality, 6%), 13 (3%) for patients with an intact ventricular septum and 24 (13%) for those with a ventricular septal defect (P < .001). In 36% delayed sternal closure was performed, 8% required peritoneal dialysis, and 2% required mechanical circulatory support. Median ventilation time was 58 hours, and intensive care and hospital stay were 6 and 14 days, respectively. Although of various preoperative risk factors the presence of a ventricular septal defect, arch pathology, and coronary anomalies were univariate predictors of operative mortality, only the presence of a ventricular septal defect approached statistical significance (P = .06) on multivariable analysis. Of various operative parameters, aortic crossclamp time and delayed sternal closure were also univariate predictors; however, only the latter was an independent statistically significant predictor of death. CONCLUSIONS: Results of the procedure in European centers are compatible with those in the literature. The presence of a ventricular septal defect is the clinically most important preoperative risk factor for operative death, approaching statistical significance on multivariable analysis.

Results of surgery for Ebstein anomaly: a multicenter study from the European Congenital Heart Surgeons Association.

OBJECTIVE: Since most centers' experience with Ebstein anomaly is limited, we sought to analyze the collective experience of participating institutions of the European Congenital Heart Surgeons Association with surgery for this rare malformation. METHODS: The records of all 150 patients (median age 6.4 years) who underwent surgery for Ebstein anomaly in the 13 participating Association centers between January 1992 and January 2005 were reviewed retrospectively. Patients with congenitally corrected transposition were excluded. RESULTS: Most patients (81%) had Ebstein disease type B or C and significant functional impairment (61% in New York Heart Association class III or IV) and 16% had prior operations. Surgical procedures (n = 179) included valve replacement (n = 60, 33.5%), valve repair (n = 49, 27.3%), 1(1/2) ventricle repair (n = 46, 25.6%), palliative shunt (n = 13, 7.26%), and other complex procedures (n = 11, 6.14%). There were 20 hospital deaths (operative mortality 13.3%) after valve replacement in 5 patients, valve repair in 3, 1(1/2) ventricle repair in 7, palliative procedures in 3, and miscellaneous procedures in 2. Younger age and palliative procedures were univariate risk factors for operative death, but only age was an independent predictor on multivariable analysis. CONCLUSIONS: Most patients coming to surgery presented in childhood and were significantly symptomatic. More than half underwent valve replacement or repair, but a considerable proportion had severe disease necessitating 1(1/2) ventricle repair or palliative procedures. Operative mortality did not differ significantly among repair, replacement, and 1(1/2) ventricle repair but was associated with palliative procedures for severe disease early in life, young age being the only independent predictor of operative death.