Mid-term performance of decellularized equine pericardium in congenital heart surgery.

OBJECTIVE: The aim was to report mid-term performance of decellularized equine pericardium used for repair of various congenital heart defects in the pediatric population. METHODS: A retrospective review of all patients undergoing patch implantation between 2016 - 2020 was performed. Patch quality, surgical handling, hemostasis and early patch-related complications were studied on all patients. Mid-term performance was observed in patients with ≥12 months follow-up and intact patch at discharge (without reoperation/stent implantation). RESULTS: A total of 201 patients with median age of 2.5 years [interquartile range (IQR): 0.6-6.5] underwent 207 procedures at 314 implant locations. The patch was used in following numbers/locations: 171 for pulmonary artery (PA) augmentation, 36 for aortic repair, 35 for septal defect closure, 22 for valvular repair and 50 at other locations. Early/30-day mortality was 6.5%. Early patch-related reoperations/stent implantations occurred in 28 locations (8.9%). No patch-related complications were noted except for bleeding from implant site in three locations (1%). Follow-up ≥ 12 months was available for 132 patients/200 locations. During a median follow-up of 29.7 months [IQR: 20.7-38.3], 53 patch-related reoperations/catheter reinterventions occurred (26.5%) with the majority in PA position (88.7%, 47/53). Overall 12- and 24-months freedom from patch-related reoperation/catheter reintervention per location was 91.5% (95% CI: 86.7%-94.6%) and 85.2% (95% CI: 78.9%-89.6%) respectively. CONCLUSION: Decellularized equine pericardium used for repair of various congenital heart defects showed acceptable mid-term performance. Reoperation/reintervention rates were in a range as observed with other xenogeneic materials previously reported articles, occurring most frequently after PA augmentation.

Coagulation Profile of Neonates Undergoing Arterial Switch Surgery With Crystalloid Priming of the Cardiopulmonary Bypass Circuit.

OBJECTIVES: The aim was to evaluate changes in the coagulation profile of cyanotic neonates, to analyze the effects of cardiopulmonary bypass (CPB) with crystalloid priming on their coagulation status, and to determine factors predicting a requirement for hemostasis-derived transfusion. DESIGN: Retrospective cohort. SETTING: Single-center, tertiary academic hospital. PARTICIPANTS: In total, 100 consecutive neonates who underwent arterial switch surgery between December 2014 and June 2020. INTERVENTIONS: Rotational thromboelastometry (ROTEM) and coagulation parameters before surgery and before termination of CPB were evaluated. Transfusion of platelets, fresh frozen plasma, and fibrinogen, defined as hemostasis-derived transfusion (HD transfusion), were determined. Patients with and without HD transfusion were compared to identify predictors. MEASUREMENTS AND MAIN RESULTS: After CPB, fibrinogen was reduced by 24.5% (interquartile range [IQR] 8.9-32.1) to 201 mg/dL (IQR 172-249), resulting in a reduction of FIBTEM A10 by 20% (1.8-33.3) to 8 mm (6-11). The platelet count decreased by a median of 47.2% (25.6-61.3) to 162 × 103/µL (119-215). However, the median fibrinogen concentration and platelet count remained within normal range. Neonates with abnormal ROTEM results were more likely to receive HD transfusions. The HD transfusions were more likely with lower preoperative FIBTEM maximum clot firmness values (p = 0.031), lower hemoglobin concentrations at termination of CPB (p = 0.02), and longer CPB duration (p = 0.017). Perioperative hemostasis without any HD transfusion was achieved in 64 neonates. CONCLUSIONS: Guidance from ROTEM analyses facilitates hemostasis management after neonatal CPB. Circuit miniaturization with transfusion-free CPB is associated with acceptable changes in ROTEM in most patients, and allows sufficient hemostasis without any HD transfusions in most patients.

Acute Kidney Injury After Neonatal Aortic Arch Surgery: Deep Hypothermic Circulatory Arrest Versus Moderate Hypothermia With Distal Aortic Perfusion.

BACKGROUND: Acute kidney injury (AKI) is a common complication observed after neonatal aortic arch repair. We studied its incidence after procedures carried out using deep hypothermic circulatory arrest (DHCA) versus moderate hypothermia with distal aortic perfusion (MHDP), usually through the common femoral artery. In both groups, continuous regional cerebral perfusion (RCP) was used during the time required for aortic arch repair. METHODS: A total of 125 neonates underwent aortic arch repair. Between 2007 and 2012, DHCA with RCP was used in 51 neonates. From 2013 to 2019, MHDP with RCP was performed on 74 newborns. Operative complexity was similar in both periods. Acute kidney injury was defined as a significant elevation of serum creatinine and was classified according to the neonatal modified n-KDIGO (neonatal Kidney Disease: Improving Global Outcomes) stages 1 to 3 (Kidney Disease Improving: Global Outcomes). RESULTS: Acute kidney injury was observed in a total of 68 patients (68/125: 54.4%). In the majority (44/68: 64.7%), n-KDIGO stage 1 occurred. Stage 2 (n = 14) and stage 3 (n = 10) were observed more frequently after DHCA versus MHDP: 29.4% (15/51) versus 12.2% (9/74), P = .02. At cardiopulmonary bypass end, lactate levels were significantly higher (P = .001) after DHCA: 3.4 (2.9-4.3) mmol/L compared to 2.7 (2.3-3.7) mmol/L after MHDP. Early mortality was 12% (15/125) in the entire cohort. It was 17.6% (9/51) after DHCA versus 8.1% (6/74) after MHDP, however not statistically significant (P = .16). CONCLUSION: Mild (stage 1) AKI occurred frequently after neonatal aortic arch repair. The use of MHDP was associated with a significantly lower incidence of moderate (stage 2) and severe (stage 3) AKI forms.

Surgical management of Ebstein anomaly: impact of the adult congenital heart disease anatomical and physiological classifications.

OBJECTIVES: Our goal was to evaluate the impact of the adult congenital heart disease anatomical and physiological (ACHD AP) classification system on the surgical management of Ebstein anomaly (EA) in adult patients. METHODS: From February 2000 through August 2017, data of patients aged at least 16 years, who underwent primary EA surgery, were retrospectively evaluated. The cohort was divided in 2 groups according to their ACHD AP classification: the moderate EA group (IIB, IIC) and the severe EA group (IID). Survival, freedom from reoperation and freedom from occurrence of major adverse advents were estimated. RESULTS: There were 33 patients (21 women, 12 men). Eighteen belonged to the moderate group, 15 to the severe group. There were 12 female patients (80%) in the severe group. Patients in the moderate group were younger than those in the severe group (P = 0.02): 32 ± 12 vs 44 ± 15 years old. Thirty tricuspid valve repairs and 3 replacements were performed. Repair was mainly performed in the moderate group (P = 0.02). Overall survival was 90.1 ± 5.4% at 9 months after the operation and did not change in the later follow-up period. It was 100% for patients in the moderate group and 80.0 ± 10.3% in the severe group (P = 0.07), and 75.0 ± 12.5% for female patients of in the severe group compared to 100% for the remaining patients (P = 0.025). Survival free from major adverse events, including reoperation, at 10 years was 60.0 ± 12.6% in the moderate and 38.1% ± 12.9% in the severe group (P = 0.03). No patient in the moderate group evolved to be in the severe group at late follow-up. CONCLUSION: Adult EA patients should undergo surgery earlier when they are still in the moderate ACHD AP classification.

Fast-track extubation after cardiac surgery in infants: Tug-of-war between performance and reimbursement?

OBJECTIVES: To compare the safety and resource-efficacy of the fast-track (FT) concept (extubation ≤8 hours after surgery) versus the conventional approach (non-FT, >8 hours postoperatively) in infants undergoing open-heart surgery. METHODS: Infants <7 kg operated on cardiopulmonary bypass between 2014 and 2018 were analyzed. Propensity score matching (1:1) was performed for group comparison (FT vs non-FT). Intensive care unit (ICU) personnel use and unit performance were evaluated. Postoperative outcome and reimbursement based on German diagnosis-related groups were compared. RESULTS: Of 717 infants (median age: 4 months, Society of Thoracic Surgeons-European Association for Cardio-Thoracic Surgery mortality score: 0.1-4), FT extubation was achieved in 182 infants (25%). After matching, 123 pairs (FT vs non-FT) were formed without significant differences in baseline characteristics. FT versus non-FT showed a significantly shorter ICU stay (in days): 1.8 (0.9-2.8) versus 4.2 (1.9-6.4), P < .01, and postoperative length of stay (in days): 7 (6-10) versus 10 (7-15.5), P < .01; significantly lower postoperative transfusion rates: 61.3% versus 77%, P < .01; and tendency toward lower early mortality: 0% versus 2.8%, P = .08. Reintubation rate did not differ between the groups (P = .7). Despite a decrease in personnel capacity (2014 vs 2018), the unit performance was maintained. The mean case-mix-index of FT versus non-FT was 8.56 ± 6.08 versus 11.77 ± 12.10 (P < .01), resulting in 27% less reimbursement in the FT group. CONCLUSIONS: FT concept can be performed safely and resource-effectively in infants undergoing open-heart surgery. Since German diagnosis-related group systems reimburse costs, not performance, there is little incentive to avoid prolonged mechanical ventilation. Greater ICU turnover rates and excellent postoperative outcomes are not rewarded adequately.

Subcoronary Ross/Ross-Konno operation in children and young adults: initial single-centre experience.

OBJECTIVES: We sought to evaluate the outcome after modified subcoronary Ross/Ross-Konno operation in children and young adults. METHODS: Between January 2013 and January 2019, a total of 50 patients with median age of 6.3 years (range 0.02-36.5 years, 58% males), including 10 infants (20%), received modified subcoronary Ross/Ross-Konno operation at our institution. Survival, morbidity, reinterventions, aortic valve function and aortic root dimensions were analysed. RESULTS: At a median follow-up of 31.2 months (range 14.4-51 months), there were 1 early death and 1 late death, both in the infant group. The overall survival at 5 years after the operation was 95%. Two patients needed aortic valve replacement, 11 and 15 months after their Ross operation. At 5 years, freedoms from reoperation on the autograft and on the right ventricle to pulmonary artery conduit were 94% and 97%, respectively. Freedom from aortic valve regurgitation greater than mild was 97% at 5 years. Median dimensions of the aortic root at all levels remained in normal range at last visit. Forty-four patients (95%) were in New York Heart Association class I with normal left ventricular function. CONCLUSIONS: The initial experience with the subcoronary Ross/Ross-Konno operation in children and young adults showed excellent outcome. The mortality and morbidity among infants remain significant. The described technique is reproducible and might be advantageous in situations when prosthetic supporting techniques interfere with somatic growth.

Reimbursement After Congenital Heart Surgery in Germany: Impact of Early Postoperative Extubation.

BACKGROUND: Duration of mechanical ventilation is an important variable used by German Diagnosis-Related Groups (G-DRG) system to establish cost weight values for reimbursement after congenital heart surgery. Infants are commonly ventilated after open heart surgery. As of year 2015, we strived to achieve early postoperative extubation. This work studies how this approach impacted reimbursement after infant open heart surgery. METHODS: Data of infants who underwent surgery on cardiopulmonary bypass (CPB) from 2014 to 2018 were reviewed. Successful early extubation was defined as end of mechanical ventilation within 24 hours postoperatively, without reintubation at a later point. Mean cost weight values (case mix index [CMI]) of achieved DRGs were used for estimation of reimbursement. Evolutions over years of early extubation and of reimbursement were compared. RESULTS: A total of 521 infants underwent operations on CPB. Of these, 161 (31%) procedures were of higher risk Society of Thoracic Surgery and the European Association for Cardio-Thoracic Surgery (STAT) categories 3 and 4. Early extubation was achieved in 205 (39%) patients. The rate increased from 14% (year 2014) to 57% (year 2018). Case mix index amounted to 8.87 ± 7.00 after early extubation, and 12.37 ± 7.85 after late extubation: P value <.0001. It was 8.77 ± 6.09 after early extubation in patients undergoing lower risk STAT categories 1 and 2 operations, and 8.09 ± 2.95 when categories 3 and 4 procedures were performed (P = .18). An overall 14.4% decrease in hospital reimbursement per patient was observed. CONCLUSION: Early extubation could be progressively obtained in the majority of infants. This resulted in lower reimbursement. Surgical complexity was disregarded. The current G-DRG system appears to favor longer mechanical ventilation durations after infant open heart surgery.

Adult congenital open-heart surgery: emergence of a new mortality score.

OBJECTIVES: In revised 2018 American Heart Association/American College of Cardiology guideline for the management of adults with congenital heart disease (ACHD), the committee introduced a classification that combines lesion anatomy and physiological status: ACHD anatomic physiological (AP) classification. Anatomy is described as of simple (I), moderate (II) or great (III) complexity, whereas physiology is listed in 4 categories of increasing severity (A, B, C and D). Can this classification predict early postoperative mortality? METHODS: ACHD AP classification was determined for 339 adults who underwent open-heart surgery between September 2012 and August 2018. In addition, the adult congenital heart surgery (ACHS) and Society of Thoracic Surgery-European Association for Cardio-Thoracic Surgery (STAT) mortality scores were calculated. A model based on binary logistic regression was applied. The event was early postoperative death. Mortality scores were estimated for each ACHD AP class. RESULTS: All patients could be categorized by the ACHD AP classification. The 354 procedures were performed with an early mortality of 3.4% (12/354). The mortality risk for the new mortality score, simply called ACAP score, ranged from 0.2% (95% confidence interval 0.08-0.41%) for ACHD AP class IA to 20% (16.04-24.64%) for IIID class. Observed over expected ratios of early mortality amounted to 0.87, 1.54 and 1.14, whereas areas under the curve of receiver operator characteristic were found to be 0.78, 0.64 and 0.88 for STAT, ACHS and ACAP scores, respectively. CONCLUSIONS: ACHD AP classification could embrace all procedures. In our setting, the ACAP score was more predictive of early mortality than the ACHS and STAT mortality scores. It should be validated by further studies and other centres.

Asanguineous Cardiopulmonary Bypass in Infants: Impact on Postoperative Mortality and Morbidity.

BACKGROUND: We routinely start cardiopulmonary bypass (CPB) for pediatric congenital heart surgery without homologous blood, due to circuit miniaturization, and blood-saving measures. Blood transfusion is applied if hemoglobin concentration falls under 8 g/dL, or it is postponed to after coming off bypass or after operation. How this strategy impacts on postoperative mortality and morbidity, in infants weighing ≤ 7 kg? METHODS: Six-hundred fifteen open-heart procedures performed from January 2014 to June 2018 were selected. One-hundred sixty-three patients (26.5%) were transfused on CPB (group 1), while 452 (73.5%) patients were not transfused on CPB (group 2). Operative risk and complexity were similar in both groups. Postoperative mortality and morbidity were compared. Multiple logistic regression was used to detect factors independently associated with outcome. RESULTS: Observed mortality in nontransfused group (0.7% = 3/452) was significantly lower than expected (4.2% = 19/452): p = 0.0007, and much lower than in transfused group (6.7% = 11/163): p < 0.0001. CPB transfusion (p = 0.001) was independently associated with mortality, either acting as the sole factor or in combination with the Society of Thoracic Surgeons morbidity score (p = 0.013). Patients not transfused during CPB required less frequently vasoactive inotropic drugs (p = 0.011) and duration of their mechanical ventilation was shorter (93 ± 134 hours) than for transfused patients (142 ± 170 hours): p = 0.0003. CPB transfusion was an independent determinant factor for morbidity (p = 0.05), together with body weight (p < 0.0001), vasoactive inotropic score (p < 0.0001), CPB duration (p = 0.001), and postoperative transfusion (p = 0.009). CONCLUSION: The strategy of transfusion-free CPB course, feasible in most patients ≤ 7kg, was associated with improved outcome. Asanguineous priming of CPB circuit should become standard, even in neonates and infants.

Cardiopulmonary Bypass Strategy to Facilitate Transfusion-Free Congenital Heart Surgery in Neonates and Infants.

Priming the cardiopulmonary bypass (CPB) circuit without the addition of homologous blood constitutes the basis of blood-saving strategies in open-heart surgery. For low-weight patients, in particular neonates and infants, this implies avoidance of excessive hemodilution during extracorporeal circulation. The circuit has to be miniaturized and tubing must be cut as short as possible to reduce the priming volume to prevent unacceptable hemodilution with initiating CPB. During perfusion, measures should be taken to prevent blood loss from the primary circuit to avoid replacement by additional volume. Favorable factors such as mild hypothermia/normothermia and high heparin concentrations during extracorporeal circulation promote earlier hemostasis after coming off bypass.Lower mortality score, first chest entry, higher hemoglobin concentration before going on bypass, and shorter CPB duration support transfusion-free CPB procedure. Reduced postoperative morbidity and mortality were observed when CPB was performed without blood transfusion. In our experience, this can be achieved in at least 70% of CPBs, even in low-weight patients.Bloodless CPB circuit priming should become a widespread reality, even in neonates and young infants, in any open-heart procedure.

Bloodless priming of the cardiopulmonary bypass circuit: determinants of successful transfusion-free operation in neonates and infants with a maximum body weight of 7 kg.

We currently perform open-heart procedures using bloodless priming of cardiopulmonary bypass circuits regardless of a patient's body weight. This study presents results of this blood-saving approach in neonates and infants with a body weight of up to 7 kg. It tests with multivariate analysis factors that affect perioperative transfusion. A total of 498 open-heart procedures were carried out in the period 2014-2016 and were analysed. Priming volume ranged from 73 ml for patients weighing up to 2.5 kg to 110 ml for those weighing over 5 kg. Transfusion threshold during cardiopulmonary bypass was 8 g/dl of haemoglobin concentration. Transfusion factors were first analysed individually. Variables with a p-value lower than 0.2 underwent logistic regression. Extracorporeal circulation was conducted without transfusion of blood in 335 procedures - that is, 67% of cases. Transfusion-free operation was achieved in 136 patients (27%) and was more frequently observed after arterial switch operation and ventricular septal defect repair (12/18=66.7%). It was never observed after Norwood procedure (0/33=0%). Lower mortality score (p=0.001), anaesthesia provided by a certain physician (p=0.006), first chest entry (p=0.013), and higher haemoglobin concentration before going on bypass (p=0.013) supported transfusion-free operation. Early postoperative mortality was 4.4% (22/498). It was lower than expected (6.4%: 32/498). In conclusion, by adjusting the circuit, cardiopulmonary bypass could be conducted without donor blood in majority of patients, regardless of body weight. Transfusion-free open-heart surgery in neonates and infants requires team cooperation. It was more often achieved in procedures with lower mortality score.

Results of aortic valve repair using decellularized bovine pericardium in congenital surgery.

OBJECTIVES: The search for an optimal patch material for aortic valve reconstruction (AVR) is an ongoing challenge. In this study, we report our experience of AVR using decellularized bovine pericardial patch material in congenital heart surgery. METHODS: Data of 40 consecutive patients who underwent AVR using the CardioCel® patch (Admedus Regen Pty Ltd, Perth, WA, Australia) between February 2014 and August 2016 were retrospectively reviewed. The median age of the patients at operation was 9 (2-34) years, and 18 patients were younger than 7 years. Twenty-six patients initially presented with aortic valve insufficiency (AI) and 14 with stenosis. Clinical and echocardiographic data were available until August 2017 for a median postoperative follow-up (FU) of 22 (6-42) months. RESULTS: Nine of 40 (23%) patients experienced an event during FU (death: n = 1, 2.5%; reoperation: n = 8, 20%). Overall, the probability of freedom from reoperation or death was 97 ± 3%, 76 ± 9% and 57 ± 12% at 12, 24 and 36 months of FU, respectively. Reason for reoperation was stenosis in 3 (37.5%) patients, insufficiency in 4 (50%) patients and 1 (12.5%) patient was diagnosed with aortic valve endocarditis. Of the remaining 31 patients, 2 patients are scheduled for reoperation (aortic valve stenosis: n = 1 and AI: n = 1) and 9 patients exhibit worsening of aortic valve function with moderate AI. Freedom from developing combined end point [death/reoperation/moderate degree of aortic valve dysfunction (aortic valve stenosis, AI)] after AVR was 92 ± 5%, 55 ± 9% and 28 ± 9% at 12, 24 and 36 months, respectively. CONCLUSIONS: AVR using decellularized bovine pericardial patch material in patients with congenital aortic valve disease show unsatisfactory results within the first 3 years of FU.

Modified Ross-Konno procedure in children: subcoronary implantation technique with Konno incision for annular and subannular hypoplasia.

OBJECTIVES: The technique of subcoronary autograft implantation for the Ross procedure has shown excellent durability of aortic valve function in adults. However, its use in children with hypoplastic aortic annulus or multilevel left ventricular outflow tract obstruction (LVOTO) was traditionally precluded. We combined this technique with a Konno incision and evaluated LVOTO relief and durability of the autograft function in growing patients. METHODS: Between January 2012 and January 2017, 13 patients with severe LVOTO and hypoplastic aortic annulus underwent Ross-Konno procedure with subcoronary autograft implantation. The median age at operation was 14 months. Six were infants. Concomitant procedures included resection of endocardial fibroelastosis (n = 9), mitral valvuloplasty (n = 2) and aortic arch repair (n = 1). The Konno incision was enlarged with a patch. The autograft was implanted beneath the ostia of the coronary arteries, retaining external support by the native aortic annulus. RESULTS: A newborn with hypoplastic left heart complex and Turner syndrome died in hospital: early mortality of 7.7%. No residual LVOTO or autograft regurgitation was observed at discharge. At a median follow-up of 20 months, no death had occurred. No catheter or surgical reintervention on the aortic valve or any LVOT site was needed. All peak pressure gradients across the LVOT were <10 mmHg. No autograft regurgitation was detected. CONCLUSIONS: The Ross procedure using subcoronary implantation technique combined with LVOT Konno enlargement is feasible even in patients with multilevel LVOTO and marked size discrepancy between the autograft and native aortic annulus. Longer follow-up is indicated to confirm the expected durability of the autograft function.

Assessment of a congenital heart surgery programme: a reappraisal.

OBJECTIVES: To assess our practice according to the Society of Thoracic Surgeons and the European Association for Cardio-Thoracic Surgery (STS-EACTS) Mortality Score and to the new concept of unit performance. METHODS: All main procedures carried out in the years 2012-2016 were analysed. The STS-EACTS model-based mortality risk procedure was used to calculate expected mortality. Surgical performance was estimated as the Aristotle complexity score multiplied by hospital survival. Unit performance was defined as surgical performance multiplied by the number of procedures. RESULTS: In total, 2435 procedures were analysed. One hundred and two deaths (95% confidence interval 71-135 deaths) were expected; 43 patients died after operation. Observed mortality divided by expected mortality was 0.42. The ratio ranged from 0.23 (year 2014) to 0.59 (year 2013) and was <0.6 in all STS-EACTS mortality categories. The difference between observed and expected mortality was highly significant: 1.8% vs 4.2% (P-value <0.0001). Observed surgical and unit performances were, higher than expected performances every year. Achieved surgical performance was the highest in year 2012 (7.28 ± 2.54) and the lowest in year 2014 (7.04 ± 2.52). The highest figure of unit performance was achieved in year 2016: 3980 points. CONCLUSIONS: The STS-EACTS score, currently recognized as a sound instrument to assess mortality after congenital heart surgery, overestimated postoperative mortality. If these results are confirmed by other centres, the model should be recalibrated to match the current surgical practice. Although surgical performance can evaluate outcome quality, it does not include case volume activity. Unit performance provides this information, and it integrates quality and quantity into a single value.

Additional veno-venous gas exchange as a problem-solving strategy for an oxygenator not transferring oxygen in paediatric cardiopulmonary bypass.

OBJECTIVES: Oxygenator failure during cardiopulmonary bypass constitutes a life-threatening event, especially when perfusion is conducted under normothermia. An alternative solution to emergency oxygenator changeover is described. METHODS: A supplementary oxygenator is added in the venous line without interrupting perfusion. De-airing is achieved through the cardiotomy reservoir. Oxygen supply is adapted to ensure physiologic partial oxygen pressure. RESULTS: On 5 occasions in the past 4 years, Capiox Baby FX 05 oxygenator (n = 4) and Capiox FX15 (n = 1) failed to exchange blood gases after bypass run ranging from 290 min to 563 min. Hypoxia ensued with partial oxygen pressure values of 49-79 mmHg with a fraction of inspired oxygen of 1. An additional veno-venous Terumo Capiox FX 05 oxygenator immediately improved oxygenation with resulting partial oxygen pressure increasing to at least 291 mmHg. CONCLUSIONS: An additional veno-venous oxygenator effectively corrects failing oxygenator during cardiopulmonary bypass. The method does not require circulation arrest. It does not carry the risk of air embolism. It can be carried out without any help from a second perfusionist or member of operation team.

Routine Application of Bloodless Priming in Neonatal Cardiopulmonary Bypass: A 3-Year Experience.

A restrictive transfusion strategy led us to routinely try to conduct donor-blood free open-heart surgery even in neonates. The cardio-pulmonary bypass (CPB) circuit was minimized by priming volumina at 73 ml for the smallest patients with body weight up to 2.5 kg and 85-95 ml for those with body weight of more than 2.5 kg, and by positioning the console as close as possible to operation table. Measures were applied to save blood during the procedure. Transfusion threshold of 8 g/dl hemoglobin was retained. Effort was made to avoid transfusion while on CPB or to postpone transfusion towards CPB end. From 2013 to 2015, 149 consecutive neonates underwent 150 open-heart procedures without blood in priming volume. Weight was lower than 2.5 kg in five instances. The most frequent operations were arterial switch operation (n = 54) and Norwood procedure (n = 17). Transfusion-free operation was achieved in 44 procedures. The great majority (42/44 = 95%) involved biventricular repair and included 50% (27/54) of arterial switch operations. 106 patients were transfused: 63 mostly towards CPB end, and 43 after coming off bypass. Transfusion-free procedures were associated with postoperative lower lactate concentration (p = 0.0013) and shorter duration of mechanical ventilation (p = 0.0009). Seven patients were discharged from hospital without getting any transfusion of blood or blood products. In conclusion, routine application of bloodless priming in neonatal cardiopulmonary bypass is safe and beneficial. It results into a good number (29%= 44/150) of transfusion-free operations. Postponing transfusion towards CPB end favors an overall restrictive transfusion strategy for all patients.

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.

Restrictive Atrial Septum Defect Becomes a Risk Factor for Norwood Palliation of Hypoplastic Left Heart Syndrome Only When It Is Combined with Mitral or Aortic Atresia.

BACKGROUND: Restrictive atrial septal defect (ASD) is described as risk factor for Norwood procedure because of elevated pulmonary resistance. We hypothesized that it invariably could not cause pulmonary hypertension, unless it was combined with mitral valve or aortic valve atresia. We investigated how restrictive ASD influenced survival of patients with hypoplastic left heart syndrome (HLHS) who underwent Norwood operation. PATIENTS AND METHODS: A total of 118 HLHS patients who underwent surgery between January 2005 and December 2012 were grouped into three groups. Group 1 included 31 patients with restrictive ASD combined with mitral or aortic atresia; Group 2 composed of 12 patients with restrictive ASD and mitral and aortic stenosis; Group 3 (n = 75) had no ASD restriction. Survival was determined for each group. Multivariate analysis was conducted to test risk factors for mortality. RESULTS: Mean follow-up was 26.3 ± 24.1 months. Survival was 78.7% ± 4.2% at 30-month interval and onward after Norwood procedure for the whole cohort; it was 43.8% ± 10.0%, 91.7% ± 8.0%, and 77.3% ± 5.0% for Group 1, 2, and 3, respectively. The difference was significant between Group 1 and Group 2 and 3: p < 0.001. Survival was similar for Group 2 and Group 3: p = 0.45. Combination of restrictive ASD and mitral or aortic atresia was found to be the sole risk factor for early and late mortality (odds ratio: 3.5, 95% confidence interval: 1.8-7.1, p < 0.001). CONCLUSION: Restrictive ASD only affects survival of HLHS patients following Norwood procedure if it is associated with mitral or aortic atresia.