The Society of Thoracic Surgeons Clinical Practice Guidelines on the Management of Neonates and Infants With Coarctation

BACKGROUND

Although coarctation of the aorta without concomitant intracardiac pathology is relatively common, there is lack of guidance regarding aspects of its management in neonates and infants.

METHODS

A panel of experienced congenital cardiac surgeons, cardiologists, and intensivists was created, and key questions related to the management of isolated coarctation in neonates and infants were formed using the PICO (Patients/Population, Intervention, Comparison/Control, Outcome) Framework. A literature search was then performed for each question. Practice guidelines were developed with classification of recommendation and level of evidence using a modified Delphi method.

RESULTS

For neonates and infants with isolated coarctation, surgery is indicated in the absence of obvious surgical contraindications. For patients with risk factors for surgery, medical management before intervention is reasonable. For those stable off prostaglandin E1, the threshold for intervention remains unclear. Thoracotomy is indicated when arch hypoplasia is not present. Sternotomy is preferable when arch hypoplasia is present that cannot be adequately addressed through a thoracotomy. Sternotomy may also be considered in the presence of a bovine aortic arch. Antegrade cerebral perfusion may be reasonable when the repair is performed through a sternotomy. Extended end-to-end, arch advancement, and patch augmentation are all reasonable techniques.

CONCLUSIONS

Surgery remains the standard of care for the management of isolated coarctation in neonates and infants. Depending on degree and location, arch hypoplasia may require a sternotomy approach as opposed to a thoracotomy approach. Significant opportunities remain to better delineate management in these patients.

Evaluation of end-organ protection in newborns and infants after surgery of aortic arch hypoplasia: A prospective randomized study

INTRODUCTION

Surgical repair of aortic arch hypoplasia in children requires a "dry" surgical field with reliable end-organ protection. Perfusion strategies commonly involve deep hypothermic circulatory arrest (DHCA) and variations of the continuous perfusion techniques, such as selective antegrade cerebral perfusion (SACP) and full-flow perfusion with double aortic cannulation (DAC). We aimed to evaluate the end-organ protection in the surgery of aortic arch hypoplasia in newborns and infants using DHCA and DAC.

MATERIALS AND METHODS

66 newborns and infants with aortic arch hypoplasia and biventricular anatomy were enrolled in this prospective study. Patients were randomly assigned into two groups according to the perfusion strategy - DHCA (n = 33); and DAC (n = 33). Primary endpoint: acute kidney injury (AKI), graded according to the KDIGO score. Secondary endpoints: neurological sequelae (pre- and postoperative MRI), in-hospital mortality.

RESULTS

The lowest temperature was 32 (28; 34)°С in the DAC group and 23 (20; 25)°С in the DHCA group. The patients with DAC had lower incidence of AKI (6 patients (18.2%) versus 19 patients (57.6%); p = .017). In the multivariate analysis, the inotropic index at 48 h was identified as a risk factor, increasing the risk of AKI by 4%. The DHCA group was associated with a 3.8-fold increase in the risk of AKI. There was no difference in hospital mortality between the DAC and DHCA groups (1 patient (3%) versus 3 patients (9.1%); p = .61). Neurological sequelae by MRI scan were observed in 18 patients (54.5%) in the DHCA group compared to 5 patients (15.15%) in the DAC group (p = .026). The only risk factor identified in the multivariate analysis for neurological lesions on MRI scan was the DHCA group, which increased the risk by 8.8 times.

CONCLUSIONS

Surgical reconstruction of the aortic arch hypoplasia using the method of full-body perfusion reduces the incidence of neurological lesions and renal complications requiring renal replacement therapy compared with the deep hypothermic circulatory arrest in neonates and infants.

Incidence of postoperative seizures in neonates following cardiac surgery with regional cerebral perfusion and deep hypothermic circulatory arrest

Objectives

Historically, our center has primarily used deep hypothermic circulatory arrest, but in recent years some surgeons have selectively used regional cerebral perfusion as an alternative. We aimed to compare the incidence of postoperative electroencephalographic seizure incidence in neonates undergoing surgery with regional cerebral perfusion and deep hypothermic circulatory arrest.

Methods

A retrospective analysis was performed in neonates who underwent surgery between 2012 and 2022 with either deep hypothermic circulatory arrest or regional cerebral perfusion with routine postoperative continuous electroencephalography monitoring for 48 hours. Propensity matching was performed to compare postoperative seizure risk between the 2 groups.

Results

Among 1136 neonates undergoing cardiac surgery with cardiopulmonary bypass, regional cerebral perfusion was performed in 99 (8.7%) and deep hypothermic circulatory arrest in 604 (53%). The median duration of regional cerebral perfusion was 49 minutes (interquartile range, 38-68) and deep hypothermic circulatory arrest was 41 minutes (interquartile range, 31-49). The regional cerebral perfusion group had significantly longer total support, cardiopulmonary bypass, and aortic crossclamp times. Overall seizure incidence was 11% (N = 76) and 13% (N = 35) in the most recent era (2019-2022). The unadjusted seizure incidence was similar in neonates undergoing regional cerebral perfusion (N = 12, 12%) and deep hypothermic circulatory arrest (N = 64, 11%). After propensity matching, the seizure incidence was similar in neonates undergoing regional cerebral perfusion (N = 12, 12%) and deep hypothermic circulatory arrest (N = 37, 12%) (odds ratio, 0.97; 95% CI, 0.55-1.71; P = .92).

Conclusions

In this contemporary single-center experience, the incorporation of regional cerebral perfusion did not result in a change in seizure incidence in comparison with deep hypothermic circulatory arrest. However, unmeasured confounders may have impacted these findings. Further studies are needed to determine the impact, if any, of regional cerebral perfusion on postoperative seizure incidence.

Acute renal injury after aortic arch reconstruction with cardiopulmonary bypass for children: prediction models by machine learning of a retrospective cohort study

BACKGROUND

Acute renal injury (AKI) after aortic arch reconstruction with cardiopulmonary bypass leads to injury of multiple organs and increases perioperative mortality. The study was performed to explore risk factors for AKI. We aim to develop a prediction model that can be used to accurately predict AKI through machine learning (ML).

METHODS

A retrospective analysis was performed on 134 patients with aortic arch reconstruction with cardiopulmonary bypass who were treated at our hospital from January 2002 to January 2022. Risk factors for AKI were compositive and were evaluated with comprehensive analyses. Six artificial intelligence (AI) models were used for machine learning to build prediction models and to screen out the best model to predict AKI.

RESULTS

Weight, eGFR, cyanosis, PDA, newborn birth and duration of renal ischemia were closely related to AKI. By integrating the results of the training cohort and validation cohort, we finally confirmed that the logistic regression model was the most stable model among all the models, and the logistic regression model showed good discrimination, calibration and clinical practicability. Based on 6 independent factors, the dynamic nomogram can be used as a predictive tool for clinical application.

CONCLUSIONS

DHCA could be considered in aortic arch reconstruction if additional perfusion of lower body were not performed especially when renal ischemia is greater than 30 min. Machine Learning models should be developed for early recognition of AKI.

TRIAL REGISTRATION

ChiCTR, ChiCTR2200060552. Registered 4 june 2022.

Abdominal and Peripheral Tissue Oxygen Supply during Selective Lower Body Perfusion for the Surgical Repair of Congenital Heart Disease: A Pilot Study

Background: Lower body perfusion (LBP) may be a strategy for maintaining organ perfusion during congenital heart disease surgery. It is hypothesized that renal and lower limb oxygen supply during LBP is superior to off-pump surgery and comparable to that of a standard cardiopulmonary bypass (CPB). Methods: in this prospective single-center study, patients aged <1 year were recruited if they were scheduled for a correction of aortic arch anomalies using antegrade cerebral perfusion and LBP (group 1), a repair of coarctation during aortic cross-clamping (group 2), or surgery under whole-body CPB (group 3). Renal (prefix “r”) and peripheral (prefix “p”) oxygen saturation (SO2), hemoglobin amount (Hb), blood velocity (Velo), and blood flow (Flow) were measured noninvasively. Results: A total of 23 patients were included (group 1, n = 9; group 2, n = 5; group 3, n = 9). Compared to the baseline values, rSO2 and pSO2 decreased significantly in group 2 compared to groups 1 and 3. Conversely, rHB significantly increased in group 2 compared to groups 1 and 3, reflecting abdominal venous stasis. Compared to group 3, group 1 showed a significantly lower pFlow during CPB; however, rFlow, pFlow, and pVelo did not differ. Conclusion: according to these observations, LBP results in an improved renal oxygen supply compared to off-pump surgery and may prove to be a promising alternative to conventional CPB.

Incidence and predictors of epilepsy in children with congenital heart disease

OBJECTIVE

Children with CHD may be at increased risk for epilepsy. While the incidence of perioperative seizures after surgical repair of CHD has been well-described, the incidence of epilepsy is less well-defined. We aim to determine the incidence and predictors of epilepsy in patients with CHD.

METHODS

Retrospective cohort study of patients with CHD who underwent cardiopulmonary bypass at <2 years of age between January, 2012 and December, 2013 and had at least 2 years of follow-up. Clinical variables were extracted from a cardiac surgery database and hospital records. Seizures were defined as acute if they occurred within 7 days after an inciting event. Epilepsy was defined based on the International League Against Epilepsy criteria.

RESULTS

Two-hundred and twenty-one patients were identified, 157 of whom were included in our analysis. Five patients (3.2%) developed epilepsy. Acute seizures occurred in 12 (7.7%) patients, only one of whom developed epilepsy. Predictors of epilepsy included an earlier gestational age, a lower birth weight, a greater number of cardiac surgeries, a need for extracorporeal membrane oxygenation or a left ventricular assist device, arterial ischaemic stroke, and a longer hospital length of stay.

CONCLUSIONS

Epilepsy in children with CHD is rare. The mechanism of epileptogenesis in these patients may be the result of a complex interaction of patient-specific factors, some of which may be present even before surgery. Larger long-term follow-up studies are needed to identify risk factors associated with epilepsy in these patients.

Evaluation of postoperative renal functions and its effect on body perfusion in patients with double aortic cannulation

BACKGROUND

The optimal visceral preservation method during aortic arch reconstruction is still controversial. It has been thought that double aortic cannulation is effective. Herein, it was aimed to evaluate this technique in providing distal perfusion.

METHODS

A total of 74 patients who underwent arch reconstruction between 2011 and 2019 were included. Patients were grouped according to ventricular physiology and cannulation strategies. Group 1 were univentricle patients, and all had double aortic cannulation. Group 2 were biventricular patients. Group 2A double aortic cannulation-done and Group 2B non-double aortic cannulation were included. Lactate, urea, creatinine values, renal functions, and need for peritoneal dialysis of patients were evaluated.

RESULTS

There were no complications observed due to descending aortic cannulation in any of the patients. A delayed sternal closure and the need for peritoneal dialysis were more common in the Group 1 (p < 0.01). The preoperative and postoperative 1st- and 2nd-day lactate, urea, and creatinine values in the Group 1 were higher (p < 0.05) when compared with the Group 2A and 2B. The same values were higher in Group 2A than the Group 2B (p < 0.05).

CONCLUSION

The positive effect of double aortic cannulation on renal dysfunction could not be demonstrated. This may be associated with a <1 month of age, low weight, complex surgical procedure, and high preoperative lactate, urea, and creatinine values in patients with double aortic cannulation.

Effectiveness of Repair of Aortic Coarctation in Neonates: A Long-Term experience

To evaluate early and long-term results of surgical treatment of aortic coarctation (CoAo) in neonates. This is a retrospective clinical review of neonates with CoAo, who underwent surgery between 1995 and 2019. Data were retrieved from our institutional database, to identify preoperative and postoperative characteristics. Statistical analysis was performed by means of relative risk ratio and Cox and logistic multivariate analysis. 218 consecutive neonates (M/F: 129/89, median age 11 days, IQR 7-17 days) were included; 202 (92.7%) had a left thoracotomy; 178 underwent extended end-to-end anastomosis (EEEA, 81.6%). Hypoplastic aortic arch (HAA) was present in 102 patients (46.8%); complex cardiac anomalies in 85 (39%). Significant postoperative complications occurred in 20 (9.2%). Thirty-day mortality was 2.3% (most in complex types). At a median follow-up of 10.4 years (IQR 5.6-15.0 years; FU completeness 95.9%), there were 8 late deaths (3.7%), all associated to complex CoAo. Among 196 survivors, 177 (93.2%) were in NYHA class I; re-interventions on aortic arch occurred in 9.2% (2.0% were surgical). Freedom from mortality and re-intervention on aorta at 10 years were 94.3% and 96.7%, respectively. Surgical repair of CoAo in newborns without CPB in our series was safe and low-risk, with excellent early and late outcomes.

Evolving Surgical Techniques and Improving Outcomes for Aortic Arch Surgery in Canada

Background

To explore evolving surgical techniques and outcomes for aortic arch surgery.

Methods

A total of 2435 consecutive patients underwent aortic arch repair with hypothermic circulatory arrest between 2008 and 2018 in 12 institutions across Canada. Trends in patient characteristics, surgical techniques, and in-hospital outcomes, including major morbidity or mortality, were examined.

Results

From 2008 to 2018, the age of patients (62.3 ± 13.2 years) and the proportion of women (30.2%) undergoing arch surgery did not change significantly. Aortic diameters at operation decreased (2008: 58 ± 13 mm; 2018: 53 ± 11 mm; P < 0.01). Surgeons performed more valve-sparing root replacements (2008: 0%; 2018: 15%; P < 0.001) and fewer Bentall procedures (2008: 27%; 2018: 20%; P < 0.01). Total arch replacement rates were similar (P = 0.18); however, elephant trunk (2008: 9.5%; 2018: 19%; P < 0.001) and frozen elephant trunk (2008: 3.1%; 2018: 15%; P < 0.001) repair rates have increased. Over time, higher nadir temperatures (2008: 18 [17-21]°C; 2018: 25 [23-28]°C; P < 0.001), and more frequent antegrade cerebral perfusion (2008: 61%; 2018: 83%; P < 0.001) were used. For elective cases, in-hospital mortality rates declined (2008: 6.8%; 2018: 1.2%; P = < 0.01), as did major morbidity or mortality (2008: 24%; 2018: 13%; P < 0.001) and transfusion rates (2008: 61%; 2018: 41%; P < 0.001), but stroke rates remained constant (2008: 6.8%; 2018: 5.3%; P = 0.12). Outcomes remained the same over time for urgent or emergent cases.

Conclusions

Outcomes have improved over the past decade in Canada for elective aortic arch surgery, in the context of operating on smaller aortas, and more frequent use of moderate hypothermia and antegrade cerebral perfusion. Further research is needed to improve stroke rates and outcomes in the emergency setting.

Near-Infrared Spectroscopy Assessment of Tissue Oxygenation During Selective Cerebral Perfusion for Neonatal Aortic Arch Reconstruction

Objective: Optimal selective cerebral perfusion (SCP) management for neonatal aortic arch surgery has not been extensively studied. We induced mild hypothermia during SCP and used the tissue oxygenation monitor to ensure adequate perfusion during the cardiopulmonary bypass (CPB). Methods: Eight cases were recruited from September 2018 to April 2020. SCP was maintained at 30°C, and CPB was adjusted to achieve a mean right radial artery pressure of 30 mmHg. The near-infrared tissue saturation (NIRS) monitor was applied to assess the right and left brain, flank, and lower extremity during the surgery. Results: During surgery, the mean age was 4.75 days, the mean body weight was 2.92 kg, the CPB duration was 86.5 ±18.7 min, the aortic cross-clamp time was 46.1 ± 12.7 min, and the SCP duration was 14.6±3.4 min. The brain NIRS before, during, and after SCP was 64.2, 67.2, and 71.5 on the left side and 67.9, 66.2, and 70.1 on the right side (p = NS), respectively. However, renal and lower extremity tissue oxygenation, respectively decreased from 61.6 and 62.4 before SCP to 37.7 and 39.9 after SCP (p < 0.05) and then increased to 70.1 and 90.4 after full body flow resumed. No stroke was reported postoperatively. Conclusion: SCP under mild hypothermia can aid in efficient maintenance of brain perfusion during neonatal arch reconstruction. The clinical outcome of this strategy was favorable for up to 20 min, but the safety duration of lower body ischemia warrants further analysis.

Study on the differential proteomics of rat hippocampal mitochondria during deep hypothermic circulatory arrest

BACKGROUND

This study aimed to investigate the effect of deep hypothermic circulatory arrest (DHCA) on rat hippocampal mitochondrial protein expression and its differential proteomics, and explore the potential mechanisms behind the effect.

METHODS

We used internal jugular vein reflux and tail artery perfusion methods to establish the rat cardiopulmonary bypass (CPB) model. Rats were dissected to obtain the hippocampus, and the hippocampal mitochondria were purified. The mitochondrial morphology and the mitochondrial marker cytochrome C oxidase (COX) qualitatively examined via transmission electron microscopy and western-blot analysis, respectively. The qualified samples were subjected to isobaric tags for relative and absolute quantification (iTRAQ); we then established the CPB model again to obtain the rat hippocampus for cryoultramicrotomy, and used immunofluorescent double staining technique to qualitatively and semi-quantitatively verify two representative differentially expressed proteins.

RESULTS

By searching the Mascot 2.2 database, 29 differentially expressed proteins were obtained with statistical significance, including 21 known proteins and 8 unknowns. The expression level of COX and monoacylglycerol lipase did not change significantly (P>0.05) during the hyperacute phase; however, their intracellular localizations were altered.

CONCLUSIONS

DHCA induced the differential expression of 29 rat hippocampal mitochondrial proteins, some of which had altered intracellular localization. We speculated that the localized alteration of these proteins is one of the neuroprotection mechanisms that occurs during DHCA.

Total circulatory arrest as a support modality in congenital heart surgery: review and current evidence

The use of total circulatory arrest (TCA)/deep hypothermic circulatory arrest (DHCA) as a support modality in congenital heart surgery is a time-tested strategy. However, with technological advances, the widespread use of this technique has decreased. Adjunctive cerebral perfusion with continuous cardiopulmonary bypass (CPB) gradually has become more popular with a view to reduce the complications related to DHCA. In addition, better neuromonitoring and neuroprotective strategies have made DHCA much safer. However, the level of evidence to support the best way to protect the brain during congenital heart surgery is insufficient. This review analyzes the history, physiology, techniques of DHCA, as well as other alternative strategies like selective cerebral perfusion and presents the current available evidence.

Short- and midterm outcomes of aortic arch reconstruction: Beating heart versus cardiac arrest

OBJECTIVES

We aimed to compare the short- and midterm results of perfusion strategies used for arch reconstruction surgery.

MATERIAL AND METHODS

One hundred and seventy-three consecutive patients who underwent aortic arch reconstruction surgery for transverse arcus hypoplasia between January 2011 and February 2020 were retrospectively analyzed. The patients were divided into two groups, as beating heart (BH) group and cardiac arrest (CA) group.

RESULTS

The CA group comprised 60 (35%) patients and the remaining 113 (65%) patients were in the BH group. The median age of the patients was 30 (interquartile range: 18-95) days. The incidences of acute renal failure (ARF) and delayed sternal closure were higher in the CA group (p = .05, <.001, respectively). Balloon angioplasty was performed in 5 (2%) patients and reoperation was performed in 11 (6%) patients due to restenosis. There were no statistically significant differences between the two groups in terms of reoperation or reintervention rates (p = .44 and .34, respectively).

CONCLUSIONS

Both strategies were associated with satisfactory midterm prevention of reintervention and reoperation. Given the lower incidence of ARF and delayed sternal closure in the postoperative period and similar midterm outcomes, we believe that the BH strategy is preferable.

Avoiding use of total circulatory arrest in the practice of congenital heart surgery

Deep hypothermic circulatory arrest (DHCA) technique has been an important armamentarium in the correction of congenital heart diseases. There have been many controversies and concerns associated with DHCA, particularly neurological damage. Selective ante grade cerebral perfusion (SACP) was introduced as an adjunct to DHCA with the objective of limiting the neurologic injury during aortic arch repairs. Over the past two decades, various aspects of cardiopulmonary bypass and DHCA have been studied and modified such as optimisation of flows, anti-inflammatory interventions, haematocrit, and temperature to improve neurologic outcomes. With the changes in practice of DHCA, outcomes have significantly improved but SACP intuitively appears attractive to offer better neuroprotection. The strategy of conduct of SACP is evolving and needs to be standardised for comparing outcomes. In this review we have discussed the various physiological and technical factors involved in conduct of SACP in paediatric cardiac surgery and outcomes with SACP.

MHCA with SACP versus DHCA in Pediatric Aortic Arch Surgery: A Comparative Study

The safety and efficacy of selective antegrade cerebral perfusion (SACP) in children undergoing aortic arch surgery are unclear. In this retrospective analysis, we compared moderate hypothermic circulatory arrest (MHCA; n = 61) plus SACP vs deep hypothermic circulatory arrest (DHCA; n = 53) in children undergoing aortic arch surgery during a period from January 2008 to December 2017. Demographic characteristics and the underlying anomalies were comparable between the two groups. The MHCA + SACP group had shorter cardiopulmonary bypass (CPB) time (146.9 ± 40.6 vs 189.6 ± 41.2 min for DHCA; p < 0.05) and higher nasopharyngeal temperature (26.0 ± 2.1 vs 18.9 ± 1.6 °C; p < 0.01). The MHCA + SACP group had lower rate of neurologic complications (3/61 vs 10/53 for DHCA; p < 0.05) but not complications in other organ systems. The MHCA + SACP group also had less 24-hour chest drainage (median, interquartile rage: 28.9, 12.6–150.0 vs 47.4, 15.2–145.0 ml/kg for DHCA; p < 0.05), shorter duration of postoperative mechanical ventilation (35.0, 15.4–80.3 vs 94.0, 42.0–144.0 h; p < 0.01), and shorter stay in intensive care unit (3.9, 3.0–7.0 vs 7.7, 5.0–15.0 d; p < 0.05). In regression analysis, in-hospital mortality was associated with longer CPB time. In conclusion, MHCA + SACP is associated with better short-term outcomes in children receiving aortic arch surgery under CPB.

Selective Antegrade Cerebral Perfusion With or Without Additional Lower Body Perfusion During Aortic Arch Reconstruction in Infants

BACKGROUND

Aortic arch reconstruction is often challenging, especially in infants, owing to its high postoperative complication risks. This study aimed to compare the effectiveness between selective antegrade cerebral perfusion (SACP) alone and SACP in combination with continuous lower body perfusion with descending aortic cannulation (DAC) in preserving renal function, and to determine the influence of perfusion strategy on the postoperative course of infants who underwent aortic arch reconstruction.

MATERIAL AND METHODS

A total of 121 infants who underwent aortic arch reconstruction between January 2008 and December 2018 were included in the analysis. Patients (median age: 29 days, range: 3-270 days) were divided into the following groups: those who underwent repair with SACP (SACP group, 79 patients) and those who underwent additional lower body perfusion (DAC group, 42 patients).

RESULTS

Three (7.1%) and nine (11.4%) patients died in the DAC and SACP groups, respectively (P = .54). The SACP group had more patients requiring renal replacement therapy (P = .002) and higher incidence of second stage acute kidney injury (AKI) development (Kidney disease improving global outcomes (KDIGO) criteria; P = .032). The SACP group had higher frequency of open chest postoperatively than the DAC group (P = .011). The DAC group had lower vasoactive inotropic score (VIS) at the first postoperative day (P < .001) and shorter intensive care unit length of stay (P = .050). There was no difference in neurological complications between the groups (P = .061). High VIS was associated with early mortality (odds ratio [OR]: 1.79 [1.33-2.41], P < .001) and AKI (OR: 1.60 [1.35-1.91], P < .001). The DAC perfusion strategy with minimal hypothermia was associated with lower risk of AKI (OR: 0.91 [0.84-0.98], P = .016).

CONCLUSION

Antegrade cerebral perfusion with continuous lower body perfusion via DAC could effectively be used for improving early postoperative results among infants undergoing procedures that include aortic arch reconstruction.

"Aorta-clamp" technique for surgical repair of acute type A aortic dissection-5 min circulatory arrest at 30 °C

Background

Deep hypothermic circulatory arrest (HCA), which causes perioperative complications, is the foundation of surgical treatment for acute type A aortic dissection (AAAD). To extensively replace the dissected aorta and avoid the negative impacts of HCA, we developed an "aorta-clamp" technique and examined its efficacy in repairing AAAD.

Methods

From November 2014 to August 2016, we recruited 59 consecutive patients (51.3±10.9 years) with AAAD into this study. We performed total arch replacement combined with an elephant trunk implantation using the "aorta-clamp" technique under a 30 °C HCA with continual bilateral antegrade cerebral perfusion.

Results

The average HCA time was 4.9±1.0 min. Twenty-three patients had increased serum creatinine (sCr) before surgery, suggesting an AAAD-associated acute kidney injury (AKI). The sCr level returned to normal in five patients after operation and in 15 before discharge. Six patients (10.2%) with preoperative AKI required postoperative dialysis, and two of these patients (3.4%) died of multiple organ failure. Two patients (3.4%) required re-exploration due to bleeding. One patient (1.7%) exhibited temporary neurologic deficits. There were no late deaths. Computed tomography (CT) examination confirmed the patency of the anastomotic sites and thrombus obliteration of the residual false lumen.

Conclusions

Using the "aorta-clamp" technique with continual bilateral antegrade cerebral perfusion, total arch replacement combined with an elephant trunk implantation can be performed under five minutes of mild (30 °C) HCA. Our data suggest that this technique for the surgical repair of AAAD is a safe, feasible and effective surgical approach with satisfactory early outcomes.

Neurodevelopmental outcomes of children with congenital heart disease: A review

Congenital heart defects are the most common birth anomaly affecting approximately 1% of births. With improved survival in this population, there is enhanced ability to assess long-term morbidities including neurodevelopment. There is a wide range of congenital heart defects, from those with minimal physiologic consequence that do not require medical or surgical intervention, to complex structural anomalies requiring highly specialized medical management and intricate surgical repair or palliation. The impact of congenital heart disease on neurodevelopment is multifactorial. Susceptibility for adverse neurodevelopment increases with advancing severity of the defect with initial risk factors originating during gestation. Complex structural heart anomalies may pre-dispose the fetus to abnormal circulatory patterns in utero that ultimately impact delivery of oxygen rich blood to the fetal brain. Thus, the brain of a neonate born with complex congenital heart disease may be particularly vulnerable from the outset. That vulnerability is compounded during the newborn period and through childhood, as this population endures a myriad of medical and surgical interventions. For each individual patient, these factors are likely cumulative and synergistic with progression from fetal life through childhood. This review discusses the spectrum of risk factors that may impact neurodevelopment in children with congenital heart disease, describes current recommendations and practices for neurodevelopmental follow-up of children with congenital heart disease and reviews important neurodevelopmental trends in this high risk population.

Direct Arterial Cannulation Allows Easy and Safe Continuous Selective Cerebral Perfusion During Repair of Interrupted Aortic Arch Even for Low Birth Weight Neonates

OBJECTIVES

To review the outcomes of direct innominate artery cannulation for continuous cerebral perfusion used for repair of interrupted aortic arch (IAA) in a consecutive cohort of neonates regardless of weight.

METHODS

Between September 1999 and April 2016, forty-four children with IAA (18 type A and 26 type B) underwent repair using continuous, hypothermic (18°C) low-flow cerebral perfusion via direct innominate artery cannulation. Associated cardiac lesions were truncus arteriosus (TA; 5), ventricular septal defect (VSD; 30), transposition of the great arteries (TGA; 1), unbalanced atrioventricular septal defect (1), double-inlet left ventricle (1), double-outlet right ventricle (3), and aortopulmonary window (APW; 5). Truncus arteriosus, single VSD, TGA, and APW were corrected while the other patients were palliated.

RESULTS

Age at the time of surgery was 7 days (4-120 days) and weight 3.1 kg (2.1-5.8 kg). Selective cerebral perfusion was maintained in all patients. During the selective cerebral perfusion, perfusion flow rate was maintained at 30 mL/kg/min. Aortic cross-clamp time, low-flow, and total cardiopulmonary bypass time were 63 (40-116), 28 (17-41), and 108 (80-217) minutes, respectively. There were no deaths nor clinical evidence of neurological injury. Postoperative ventilation time, length of intensive care unit, and hospital stay were 3 (2-14), 5 (3-21), and 13 (6-27) days, respectively. Follow-up, complete at 84 months (24-221), revealed no late clinically evident neurologic sequelae nor innominate artery complications.

CONCLUSIONS

Direct innominate arterial cannulation with continuous selective cerebral perfusion can be safely applied for repair of IAA even in low birth weight neonates. It is technically simple and associated with excellent clinical outcomes.

Double-arterial cannulation: a strategy for whole body perfusion during aortic arch reconstruction

OBJECTIVES

Double-arterial cannulation enables cerebral perfusion and lower body perfusion during aortic arch reconstruction. The aim of this study was to analyse and report our experience of using this cannulation and perfusion technique on paediatric patients.

METHODS

A retrospective single-centre study was carried out on 407 consecutive paediatric patients who underwent an aortic arch reconstruction under double-arterial cannulation between 2003 and 2015. The median age of the patients at surgery was 8 (range 2-5570) days, and body weight was 3.3 (range 1.8-60) kg. All operations were performed through standard median sternotomy. One arterial cannula was inserted into the innominate artery and the second one into the supradiaphragmatic descending aorta. Primary end points were 30-day mortality, acute renal failure requiring dialysis and time until lactate level decreased to ≤2 mmol/l postoperatively.

RESULTS

We found an in-hospital mortality of 8.6%. Lethal incident was not associated with the cannulation method, and 1 intraoperative lesion of the descending aorta could be repaired immediately. The median lactate level of the patients on arrival at the intensive care unit was 3.5 mmol/l [quartile (Q)1: 2.3-Q3: 4.7] and creatinine was 0.48 mg/100 ml (Q1: 0.40-Q3: 0.58). The longest duration until the lactate level decreased to ≤ 2 mmol/l was found in the group of 264 univentricular patients (median 11 h, Q1: 6-Q3: 24). Seven (1.7%) patients of the whole cohort required peritoneal dialysis postoperatively.

CONCLUSIONS

Double-arterial cannulation is a simple and safe method for perfusing the brain and the lower parts of the body during aortic arch reconstruction. Perioperative survival and freedom from procedure-related complications in this demanding patient population are encouraging.

Surgical repair of aortic coarctation in pediatric age: A single center two decades experience

BACKGROUND

To evaluate early and long-term results of surgical treatment of aortic coarctation (CoAo) in infants and children.

METHODS

A retrospective clinical review of patients less than 18 years with CoAo, undergoing surgery between 1995 and 2015. Data were retrieved from our institutional database, to identify preoperative and postoperative characteristics. Statistical analysis was performed by bivariate, Cox's, and logistic regression analysis.

RESULTS

Three hundred forty-one consecutive patients (male/female: 192/149; the median age at surgery of 25 days; interquartile range [IQR], 10-143 days) were included; 187 patients were less than 1 month (54.9%); 276 underwent extended end-to-end anastomosis (EEEA) (80.9%). Hypoplastic aortic arch (HAA) occurred in 34.6% and bicuspid aortic valve in 21.1%. The isolated type was present in 249 (73.0%). Significant postoperative complications occurred in 5.6%. Thirty-day mortality was 1.4%. At a median follow-up of 10.2 years (IQR, 6-15 years; FU completeness, 91.2%), there were eight late deaths (2.6%), most in the complex type. Among 298 survivors, 284 (95.3%) were in NYHA class I; 10 (3.0%) were on antihypertensive treatment. Reinterventions on aortic arch occurred only in 4.5%, being HAA a significant risk factor for reoperation ( P = 0.00173). Freedom from mortality and reintervention on aorta at 21 years were 93.5% and 93.6%, respectively.

CONCLUSIONS

Surgical repair of CoAo by EEEA without CPBP is a safe and low-risk procedure, concerning either early or late outcomes, despite the presence of HAA and neonatal age can influence recoarctation. Most patients are clinically well in the long-term, and only a few require antihypertensive therapy.

Recent Advances in Congenital Heart Surgery: Alternative Perfusion Strategies for Infant Aortic Arch Repair

PURPOSE OF REVIEW

This paper will discuss current cannulation strategies for infant aortic arch repair and compare them to more traditionally used techniques.

RECENT FINDINGS

Aortic arch reconstruction in infants has traditionally involved deep hypothermic circulatory arrest which results in total body ischemia. This has been associated with an increased risk of morbidity including bleeding, renal dysfunction, and neurologic injury. Advances in perfusion techniques have allowed for preserved perfusion to the brain during arch repair. Current techniques have further evolved that allow for continuous perfusion of the heart and even the lower body during arch reconstruction. With current techniques, aortic arch reconstruction in infants can be performed with continuous perfusion to the brain, heart, and lower body. Further technical refinements will be helpful, and study is necessary to evaluate the benefit of these strategies.

Selective versus standard cerebro-myocardial perfusion in neonates undergoing aortic arch repair: A multi-center study

The results of neonatal aortic arch surgery using cerebro-myocardial perfusion were analyzed. Selective cerebral and myocardial perfusion, using two separate pump rotors, was compared with standard perfusion, using a single pump rotor with an arterial line Y-connector. Between May 2008 and May 2016, 69 consecutive neonates underwent arch repair using either selective cerebro-myocardial perfusion (Group A, n = 34) or standard perfusion (Group B, n = 35). The groups were similar for age, weight, BSA, prevalence of one-stage or staged repair, and single ventricle palliation; male gender was more frequent in Group A. The duration of the cerebro-myocardial perfusion was comparable (27 ± 8 vs. 28 ± 7 min, P = 0.9), with higher flows in Group A (57 ± 27 vs. 39 ± 19 mL/kg/min, P = 0.01). Although cardioplegic arrest was more common in Group B (13/34 vs. 23/35, P = 0.03), the duration of myocardial ischemia was longer in Group A (64 ± 41 vs. 44 ± 14 min, P = 0.04). There was 1 hospital death in each group, with no permanent neurological injury in either group. Cardiac morbidity (1/34 vs. 7/35, P = 0.02) was more common in Group B, while extracardiac morbidity was similar in both the groups. During follow-up (3.2 ± 2.4 years), 5 late deaths occurred with a comparable 5-year survival rate (75 ± 17% vs. 88 ± 6%, P = 0.7) and freedom from arch reintervention (86 ± 6% vs. 84 ± 7%, P = 0.6). Risk of cardiac morbidity was greater with standard cerebro-myocardial perfusion (OR = 5.2, CI 3.3-6.8, P = 0.001) and with perfusion flows less than 50 mL/kg/min (OR 3.7, CI 1.87-5.95, P = 0.04). Cerebro-myocardial perfusion is a safe and effective strategy to protect the brain and heart in neonates undergoing arch repair. Selective techniques using higher perfusion flows may further attenuate cardiac morbidity.

Supplemental Perfusion Techniques for Aortic Arch Reconstruction, With Emphasis on Direct Cannulation of the Descending Aorta

The established techniques of deep hypothermia with circulatory arrest and regional cerebral perfusion expose infants and children to additional physiologic stress and deleterious effects which may adversely affect the outcome of operations involving reconstruction of the aortic arch. Alternative techniques to supplement perfusion support are an area of innovation today. The most effective adjunct for somatic perfusion during arch reconstruction is direct cannulation of the innominate artery and the descending aorta, with full flow at mild hypothermia distributed throughout the entire body just as it is during routine, single cannulation surgery with an intact aorta. Detailed facilitating techniques for descending aortic cannulation are discussed.

A Review of Goal-Directed Cardiopulmonary Bypass Management in Pediatric Cardiac Surgery

Cardiopulmonary bypass perfusion management significantly affects postoperative outcomes. In recent years, the principles of goal-directed therapy have been applied to the field of cardiothoracic surgery to improve patient outcomes. Goal-directed therapy involves continuous peri- and postoperative monitoring of vital clinical parameters to tailor perfusion to each patient's specific needs. Closely measured parameters include fibrinogen, platelet count, lactate, venous oxygen saturation, central venous oxygen saturation, mean arterial pressure, perfusion flow rate, and perfusion pulsatility. These parameters have been shown to influence postoperative fresh frozen plasma transfusion rate, coagulation state, end-organ perfusion, and mortality. In this review, we discuss the recent paradigm shift in pediatric perfusion management toward goal-directed perfusion.

Deep hypothermic circulatory arrest or tepid regional cerebral perfusion: impact on haemodynamics and myocardial integrity in a randomized experimental trial

OBJECTIVES

Organ protective management during aortic arch surgery comprises deep hypothermic (18°C) circulatory arrest (DHCA), or moderate hypothermia (28°C/ 'tepid') with regional cerebral perfusion (TRCP). The aim of this experimental study was to evaluate the effect of distinct organ protective management on hemodynamic performance and myocardial integrity.

METHODS

Ten male piglets were randomized to group DHCA (n = 5) or TRCP (n = 5) group and operated on cardiopulmonary bypass (CPB) with 60 min of aortic cross-clamping. Blood gas analysis was performed throughout the experiment. Haemodynamic assessment was performed using a thermodilution technique before and after CPB. Myocardial biopsies were taken 2 h after CPB and evaluated using terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate-biotin nick-end labelling assay and western blot analysis.

RESULTS

At reperfusion, levels of central venous saturation were significantly higher (P = 0.016) and levels of lactate significantly lower (P = 0.029) in the DHCA group. After CPB, thermodilution measurements revealed higher stroke volume and lower peripheral resistance in the TRCP group (P = 0.012 and 0.037). At the end of the experiment, no significant differences regarding laboratory and haemodynamic parameters were evident. All specimens showed enrichment of terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate-biotin nick-end labelling-positive cells exclusively at the left ventricular subendocardium with no difference between groups and equal concentrations of cyclo-oxygenase-2.

CONCLUSIONS

TRCP is associated with decreased peripheral resistance and higher stroke volume immediately after CPB. However, this beneficial effect is contrasted by signs of lower body hypoperfusion, which is expressed by lower central venous saturations and higher lactate levels. Distinct strategies of organ protection did not seem to affect apoptotic/necrotic and inflammatory changes in the left ventricular myocardium.

Selective Cerebro-Myocardial Perfusion in Complex Neonatal Aortic Arch Pathology: Midterm Results

Aortic arch repair in newborns and infants has traditionally been accomplished using a period of deep hypothermic circulatory arrest. To reduce neurologic and cardiac dysfunction related to circulatory arrest and myocardial ischemia during complex aortic arch surgery, an alternative and novel strategy for cerebro-myocardial protection was recently developed, where regional low-flow perfusion is combined with controlled and independent coronary perfusion. The aim of the present retrospective study was to assess short-term and mid-term results of selective and independent cerebro-myocardial perfusion in neonatal aortic arch surgery. From April 2008 to August 2015, 28 consecutive neonates underwent aortic arch surgery under cerebro-myocardial perfusion. There were 17 male and 11 female, with median age of 15 days (3-30 days) and median body weight of 3 kg (1.6-4.2 kg), 9 (32%) of whom with low body weight (<2.5 kg). The spectrum of pathologies treated was heterogeneous and included 13 neonates having single-stage biventricular repair (46%), 7 staged biventricular repair (25%), and 8 single-ventricle repair (29%). All operations were performed under moderate hypothermia and with a "beating heart and brain." Average cardiopulmonary bypass time was 131 ± 64 min (42-310 min). A period of cardiac arrest to complete intra-cardiac repair was required in nine patients (32%), and circulatory arrest in 1 to repair total anomalous pulmonary venous connection. Average time of splanchnic ischemia during cerebro-myocardial perfusion was 30 ± 11 min (15-69 min). Renal dysfunction, requiring a period of peritoneal dialysis was observed in 10 (36%) patients, while liver dysfunction was noted only in 3 (11%). There were three (11%) early and two late deaths during a median follow-up of 2.9 years (range 6 months-7.7 years), with an actuarial survival of 82% at 7 years. At latest follow-up, no patient showed signs of cardiac or neurologic dysfunction. The present experience shows that a strategy of selective and independent cerebro-myocardial perfusion is safe, versatile, and feasible in high-risk neonates with complex congenital arch pathology. Encouraging outcomes were noted in terms of cardiac and neurological function, with limited end-organ morbidity.

Perioperative Outcomes of Using Different Temperature Management Strategies on Pediatric Patients Undergoing Aortic Arch Surgery: A Single-Center, 8-Year Study

Background: With the widespread application of regional low-flow perfusion (RLFP), development of surgical techniques, and shortened circulatory arrest time, deep hypothermia is indispensable for organ protection. Clinicians have begun to increase the temperature to reduce hypothermia-related adverse outcomes. The aim of this study was to evaluate the safety and efficacy of elevated temperatures during aortic arch surgery with lower body circulatory arrest (LBCA) combined with RLFP. Methods: We retrospectively analyzed data from 207 consecutive pediatric patients who underwent aortic arch repair with LBCA & RLFP between January 2010 and July 2017 and evaluated different hypothermia management strategies. The overall cohort was divided into three groups: deep hypothermia (DH, 20.0-25.0°C), moderate hypothermia (MoH, 25.1-30.0°C) and mild hypothermia (MH, 30.1-34.0°C). Results: The percentage of AKI-1 occurrences was significantly increased in the MH group (51.52%) compared to those in the DH (25.40%) and MoH (37.84%) groups (P = 0.036); prolonged hospital stay occurrences were decreased with elevated temperature (DH 47.62%, MoH 28.83%, MH 18.18%, P = 0.006). Neurological complications, peritoneal dialysis, hepatic dysfunction, 30-day hospital mortality, delay extubation occurrences were no significant among the groups. Logistic analysis showed that the MH group was negatively associated with post-op AKI-1 compared with the DH group [OR = 0.329 (0.137-0.788), P = 0.013], no differences were found between the MoH and the MH group. Compared to other groups, the intubation time (P = 0.006) and postoperative hospital stay (P = 0.009) were significantly decreased in the MH group. Multivariate logistic analysis showed hypothermia levels were not significant with prolonged hospital stay. Conclusions: This retrospective analysis demonstrated that for pediatric patients undergoing surgeries with RLFP & LBCA, three different gradient temperature management strategies are available: deep, moderate, and mild hypothermia. Utilizing mild or moderate hypothermia is safe and feasible. Although the number of AKI-1 occurrences in the MH group was significantly increased compared to those in the other groups, further analysis showed no significance in the MoH and MH group, mild hypothermia management is as safe as others when used appropriately.

Long-term early development research in congenital heart disease (LEADER-CHD): a study protocol for a prospective cohort observational study investigating the development of children after surgical correction for congenital heart defects during the first 3 years of life

INTRODUCTION

Congenital heart disease (CHD) is the most common birth defect. Studies on the development of children with CHD point towards deficits in motoric, cognitive and language development. However, most studies are cross-sectional and there is a gap in the knowledge concerning developmental trajectories, risk and protective factors and a lack of research concerning environmental predictors. Specifically, no studies have so far considered the importance of early caregiving experiences and child temperament for the development of children with CHD.

METHODS

In a single-centre prospective cohort study, cognitive, motoric and language development of 180 children after corrective surgery for a simple transposition of the great arteries (TGA), tetralogy of Fallot (TOF) or ventricular septal defect (VSD) will be assessed at ages 12, 24 and 36 months with the Bayley Scales of Infant Development 3rd Edition (BSID-III). At age 12 months, a free-play video observation will be conducted to investigate the relationship between primary caregiver and child, and child temperament will be assessed with the Infant Behavior Questionnaire-Revised Short Version. Medical information will be obtained from patient records and demographic information via questionnaires.

ANALYSIS

Frequency and severity of developmental delays will be reported descriptively. Differences between groups (TGA, TOF, VSD) will be subjected to repeated-measures analysis across time points. Multiple regressions will be applied for the analysis of predictors at each time point. For the analysis of differential developmental trajectories, mixed-model analysis will be applied.

ETHICS AND DISSEMINATION

The study has been approved by the local medical ethics committee. Written informed consent will be obtained from all participants. Parents have the option to be debriefed about BSID-III results after each assessment and about the study results after project completion. Results will be disseminated in peer-reviewed journals and presented at conferences.

TRIAL REGISTRATION NUMBER

DRKS00011006; Pre-results.

2016 survey about temperature management during extracorporeal circulation in China

Objective:

In order to assess the current status of temperature management during cardiopulmonary bypass (CPB) in China and, thereby, implement standardized management protocols, the authors carried out a national survey about institutions performing CPB.

Method:

The survey was carried out from September 2015 to February 2016 and was supported by the Chinese Society of ExtraCorporeal Circulation. A total of 114 institutions participated, accounting for 15.64% (114/729) of the total of germane Chinese institutions, whereby, 80.85% (38/47) of the institutions had an annual surgical volume of more than 1000 cases.

Results:

The most common sites of temperature measurement were nasopharyngeal (NP) (99.12%) and rectal (92.98%) while oxygenator blood temperature was less popular (28%). Rectal temperature as the core temperature was chosen by 78.95% of the institutions; 92.11% of the institutions chose nasopharyngeal temperature to represent the cerebral temperature. During deep hypothermia circulatory arrest (DHCA) when there was no cerebral perfusion, 18 to 22℃ was the most common indication of circulatory arrest. However, with cerebral perfusion, more than 40% of the institutions maintained a lowest temperature of 22 to 25℃ for adult and pediatric patients. A NP temperature of 36 to 37℃ was chosen by 70.18% of the institutions while 81.79% chose a rectal temperature of 35 to 36.5℃ as the indication to wean from CPB. The majority of the institutions chose a difference of 10℃ between the water tank and core temperatures as the temperature gradient during rewarming. Auxiliary heat preservation techniques and equipment were used in 91.23% of the institutions, whereas 35.58% of them would lower the indications to wean from CPB.

Conclusions:

This survey accurately reflects the current situation of temperature management during CPB in institutions with an annual surgical volume of >500 cases, but has, hereby, failed to properly represent the institutions with a lower annual surgical volume.

Aortic arch reconstruction: deep and moderate hypothermic circulatory arrest with selective antegrade cerebral perfusion

OBJECTIVE

To compare the effects of moderate and deep hypothermic circulatory arrest (DHCA) with selective antegrade cerebral perfusion (SACP) during aortic arch surgery in adult patients and to offer the evidence for the detection of the temperature which provides best brain protection in the subjects who accept aortic arch reconstruction surgery.

METHODS

A total of 109 patients undergoing surgery of the aortic arch were divided into the moderate hypothermic circulatory arrest group (Group I) and the deep hypothermic circulatory arrest group (Group II). We recorded the data of the patients and their cardiopulmonary bypass (CPB) time, aortic clamping time, SACP time and postoperative anesthetized recovery time, tracheal intubation time, time in the intensive care unit (ICU) and postoperative neurologic dysfunction.

RESULTS

Patient characteristics were similar in the two groups. There were four patients who died in Group II and 1 patient in Group I. There were no significant differences in aortic clamping time of each group (111.4±58.4 vs. 115.9±16.2) min; SACP time (27.4±5.9 vs. 23.5±6.1) min of the moderate hypothermic circulatory arrest group and the deep hypothermic circulatory arrest group; there were significant differences in cardiopulmonary bypass time (207.4±20.9 vs. 263.8±22.6) min, postoperative anesthetized recovery time (19.0±11.1 vs. 36.8±25.3) hours, extubation time (46.4±15.1 vs. 64.4±6.0) hours; length of stay in the intensive care unit (ICU) (4.7±1.7 vs. 8±2.3) days and postoperative neurologic dysfunction in the two groups.

CONCLUSION

Compared to deep hypothermic circulatory arrest, moderate hypothermic circulatory arrest can provide better brain protection and achieve good clinical results.

Neurodevelopmental Outcomes in Children With Congenital Heart Disease-What Can We Impact?

OBJECTIVES

The objectives of this review are to discuss the scope of neurologic injuries in newborns with congenital heart disease, the mechanisms of injury, including prenatal, pre-, intra-, and postoperative factors, neurodevelopmental outcomes, and therapeutic strategies for the timely intervention and prevention of neurologic injury.

DATA SOURCE

MEDLINE and PubMed.

CONCLUSION

At the current time, important research is underway to 1) better understand the developing brain in the fetus with complex congenital heart disease, 2) to identify modifiable risk factors in the operating room and ICU to maximize long-term neurodevelopmental outcomes, and 3) develop strategies to improve family psychosocial health, childhood development, and health-related quality of life following hospital discharge. Crucial in this effort is the identification of an early postoperative surrogate variable with good predictive validity for long-term outcomes. If an appropriate surrogate variable for long-term outcomes can be identified, and measured relatively early after surgical intervention for complex congenital heart disease, reliable clinical trials can be undertaken to improve upon current outcomes.

Neurologic Injury Associated with Rewarming from Hypothermia: Is Mild Hypothermia on Bypass Better than Deep Hypothermic Circulatory Arrest?

Many known risk factors for adverse cardiovascular and neurological outcomes in children with congenital heart defects (CHD) are not modifiable; however, the temperature and blood flow during cardiopulmonary bypass (CPB), are two risk factors, which may be altered in an attempt to improve long-term neurological outcomes. Deep hypothermic circulatory arrest, traditionally used for aortic arch repair, has been associated with short-term and long-term neurologic sequelae. Therefore, there is a rising interest in using moderate hypothermia with selective antegrade cerebral blood flow on CPB during aortic arch repair. Rewarming from moderate-to-deep hypothermia has been shown to be associated with neuronal injury, neuroinflammation, and loss of cerebrovascular autoregulation. A significantly lesser degree of rewarming is required following mild (33-35°C) hypothermia as compared with moderate (28-32°C), deep (21-27°C), and profound (less than 20°C) hypothermia. Therefore, we believe that mild hypothermia is associated with a lower risk of rewarming-induced neurologic injury. We hypothesize that mild hypothermia with selective antegrade cerebral perfusion during CPB for neonatal aortic arch repair would be associated with improved neurologic outcome.

One-Stage Repair of an Interrupted Aortic Arch with an Aortopulmonary Window in a Premature Neonate

Interrupted aortic arch with an aortopulmonary window is a rare congenital entity that is associated with high morbidity and mortality, especially in premature low-birth-weight infants, and the proper timing of surgical correction remains a matter of debate. We present the case of a premature infant weighing 1.6 kg who successfully underwent one stage surgical repair to treat interrupted aortic arch with an aortopulmonary window. The therapeutic management of this patient is described below, and a review of the literature is presented.