Norwood Operation: Immediate vs Delayed Sternal Closure.

BACKGROUND: The Norwood operation is a complex neonatal surgery. There are limited data to inform the timing of sternal closure. After the Norwood operation, delayed sternal closure (DSC) is frequent. We aimed to examine the association of DSC with outcomes, with a particular interest in how sternal closure at the time of surgery compared with the timing of DSC. Our outcomes included mortality, length of ventilation, length of stay, and postoperative complications. METHODS: This retrospective study included neonates who underwent a Norwood operation reported in the Pediatric Cardiac Critical Care Consortium registry from February 2019 through April 2021. Outcomes of patients with closed sternum were compared to those with sternal closure prior to postoperative day 3 (early closure) and prior to postoperative day 6 (intermediate closure). RESULTS: The incidence of DSC was 74% (500 of 674). The median duration of open sternum was 4 days (interquartile range 3-5 days). Comparing patients with closed sternum to patients with early sternal closure, there was no statistical difference in mortality rate (1.1% vs 0%) and the median hospital postoperative stay (30 days vs 31 days). Compared with closed sternum, patients with intermediate sternal closure required longer mechanical ventilation (5.9 days vs 3.9 days) and fewer subsequent sternotomies (3% vs 7.5%). CONCLUSIONS: For important outcomes following the Norwood operation there is no advantage to chest closure at the time of surgery if the chest can be closed prior to postoperative day 3.

Interruption of the Ascending Aorta-Biventricular Surgical Repair.

Interruption of the ascending aorta is an extremely rare anomaly defined by a point of interruption between the intrapericardial and extrapericardial aorta and can be explained by developmental errors proximal to the embryologic right aortic sac. Herein, we present a case of interruption of the ascending aorta and describe a successful biventricular surgical repair of this unique anomaly.

Most High-Intensity Transient Signals Are Not Associated With Specific Surgical Maneuvers.

BACKGROUND: Mortality after congenital heart defect surgery has dropped dramatically in the last few decades. Current research on long-term outcomes has focused on preventing secondary neurological sequelae, for which embolic burden is suspected. In children, little is known of the correlation between specific surgical maneuvers and embolic burden. Transcranial Doppler ultrasound is highly useful for detecting emboli but has not been widely used with infants and children. METHODS: Bilateral middle cerebral artery blood flow was continuously monitored from sternal incision to chest closure in 20 infants undergoing congenital heart defect repair or palliative surgery. Embolus counts for specific maneuvers were recorded using widely accepted criteria for identifying emboli via high-intensity transient signals (HITS). RESULTS: An average of only 13% of all HITS detected during an operation were correlated with any of the surgical maneuvers of interest. The highest mean number of HITS associated with a specific maneuver occurred during cross-clamp removal. Cross-clamp placement also had elevated HITS counts that significantly differed from other maneuvers. CONCLUSIONS: In this study of infants undergoing cardiac surgery with cardiopulmonary bypass, the great majority of HITS detected are not definitively associated with a specific subset of surgical maneuvers. Among the measured maneuvers, removal of the aortic cross-clamp was associated with the greatest occurrence of HITS. Future recommended research efforts include identifying and confirming other sources for emboli and longitudinal outcome studies to determine if limiting embolic burden affects long-term neurological outcomes.

Williams Syndrome and Neonatal Cardiac Surgery for Congenital Single Ventricle.

Williams syndrome (WS) is an arteriopathic derangement associated with supravalvular aortic stenosis and branch pulmonary stenosis. We describe double-outlet right ventricle with mitral atresia and aortic arch hypoplasia in an infant with WS. This case demonstrates the difficulty in managing patients with WS with complex cardiac defects. To our knowledge, this is the first reported single-ventricle physiology in a patient with WS. (Level of Difficulty: Advanced.).

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.

Outcomes related to immediate extubation after stage 1 Norwood palliation for hypoplastic left heart syndrome.

OBJECTIVE: Immediate extubation may have outcome benefits when judiciously instituted after neonatal congenital cardiac surgery. We sought to evaluate the outcomes of immediate extubation specifically in neonates undergoing stage 1 Norwood palliation of hypoplastic left heart syndrome. METHODS: Consecutive neonates undergoing stage 1 Norwood (January 2010 to December 2016) for hypoplastic left heart syndrome were retrospectively studied. Immediate extubation was defined as successful extubation before termination of anesthetic care. Preoperative and intraoperative variables were compared between immediate extubation and nonimmediate extubation groups, and bivariate analyses and descriptive methods were used to express the association of outcome variables with immediate extubation. Data were expressed as number and percent for categoric variables, and median and interquartile range for continuous variables. RESULTS: Of 23 patients who underwent stage 1 palliation, 5 had immediate extubation (22%). There were no differences in preoperative or intraoperative factors between patients who did and did not undergo immediate extubation. There were no deaths in the immediate extubation group. In the nonimmediate extubation group, 3 patients died before hospital discharge. One patient who had immediate extubation and 4 patients among those who did not have immediate extubation had to be reintubated in the 96 hours that followed extubation (P = 1). Intensive care unit length of stay was 8 (3-17) and 8 (5-18) (days) for the immediate extubation group and nonimmediate extubation groups, respectively (P = .71). CONCLUSIONS: Immediate extubation strategy was safely accomplished in one-fifth of this cohort of hypoplastic left heart syndrome. A larger cohort may delineate the determinants of immediate extubation and its benefits in infants undergoing stage 1 single ventricle palliation.

Evaluation of cellular ingrowth within porcine extracellular matrix scaffolding in congenital heart disease surgery.

The search for an ideal material for cardiac tissue repair has led to utilization of porcine small intestinal submucosa extracellular matrix (CorMatrix). Here, we examine the histologic features of CorMatrix and the associated cellular growth at a variety of time intervals. Tissues with CorMatrix from ten patients (4 male, 6 female) with ages ranging from 2 weeks to 2 years, and implant duration ranging from 1 week to 2 years were included in this study. Samples for analysis were collected at autopsy. Surgical repair sites included great vessel repair (n=9), atrial septum defect (n=1), coronary vessels (n=1), as well as aortic (n=1) and mitral valve (n=2) leaflets. In all specimens, CorMatrix was composed of dense laminated regions of collagen, without appreciable elastin staining. In most grafts, especially those implanted for extended periods of time, tissue with luminal CD31 positivity covered the intimal surface of the CorMatrix graft. This tissue (neo-intima) consisted of spindled myofibroblasts (SMA) and small CD31 positive vessels with occasional mononuclear cells in a matrix composed of collagen, glycosaminoglycans, and rarely elastin, after extended periods of implantation. These features were readily identified in patients as early as 1 month after CorMatrix implantation. The matrix comprising the CorMatrix itself remained largely acellular, despite implantation times up to 2 years, with degradation of the graft material. We provide a framework for histologic expectations when evaluating explanted CorMatrix grafts. In this regard, the CorMatrix matrix is likely to remain acellular without significant elastin deposition, whereas the intimal and adventitial surfaces become coated by proliferating cells in a novel matrix of collagen and glycosaminoglycans.

Five-year experience with immediate extubation after arterial switch operations for transposition of great arteries.

Objectives: We sought to identify preoperative, intraoperative and anatomical factors associated with immediate extubation (IE) after arterial switch operation for d-transposition of great arteries (dTGA). Methods: This was a single-centre retrospective study performed from 1 January 2010 to 30 June 2015. IE was defined as successful extubation in the operating room (OR). Univariate/bivariate regression of preoperative, intraoperative and anatomical variables was used to determine associations with IE. Results: Of 32 patients in the dTGA spectrum (age at operation 6 days), 18 (56%) underwent IE. Twelve (71%) of the 17 patients with an intact ventricular septum and 6 (43%) of the 14 patients with ventricular septal defect (VSD) underwent IE, whereas none of the patients with double outlet right ventricle or aortic arch obstruction ( n = 4) did. Patients who had cardiopulmonary bypass time (CPB) >173 min ( P = 0.01), lowest temperature on CPB (T min) ≤ 30.4°C ( P = 0.04) and aortic cross-clamp time >86 min ( P = 0.04) were more likely to be left intubated at the end of the procedure. There was no significant difference in patient's chronological age, gestational age, post-conceptual age, weight, coronary anatomy or prevalence of VSD between those who did and did not undergo IE. There was a median increase in intensive care unit (ICU) length of stay (LOS) by 1 day (33%, P = 0.03) and ICU costs by $12 338 (15%, P = 0.06) in non-IE patients. The OR turnover time ( P = 0.09) and reintubation rate ( P = 1) at 24 h post-extubation did not differ between those who did and did not have IE. There was no myocardial dysfunction evident on predismissal echocardiography in either group. Conclusions: In this cohort of infants, post repair for TGA, 56% were extubated immediately in the OR. Greater CPB and cross-clamp times and T min ≤ 30.4°C were associated with a lesser likelihood of IE. IE was associated with shorter ICU length of stay.

Preoperative and Intraoperative Predictive Factors of Immediate Extubation After Neonatal Cardiac Surgery.

BACKGROUND: We sought to identify preoperative and intraoperative predictors of immediate extubation (IE) after open heart surgery in neonates. The effect of IE on the postoperative intensive care unit (ICU) length of stay (LOS), cost of postoperative ICU care, operating room turnover, and reintubation rates was assessed. METHODS: Patients younger than 31 days who underwent cardiac surgery with cardiopulmonary bypass (January 2010 to December 2013) at a tertiary-care children's hospital were studied. Immediate extubation was defined as successful extubation before termination of anesthetic care. Data on preoperative and intraoperative variables were compared using descriptive, bivariate, and multivariate statistics to identify the predictors of IE. Propensity scores were used to assess effects of IE on ICU LOS, the cost of ICU care, reintubation rates, and operating room turnover time. RESULTS: One hundred forty-eight procedures done at a median age of 7 days resulted in 45 IEs (30.4%). The IE rate was 22.2% with single-ventricle heart disease. Independent predictors of IE were the absence of the need for preoperative ventilatory assistance, higher gestational age, anesthesiologist, and shorter cardiopulmonary bypass. Immediate extubation was associated with shorter ICU LOS (8.3 versus 12.7 days; p < 0.0001) and lower cost of ICU care (mean postoperative ICU charges, $157,449 versus $198,197; p < 0.0001) with no significant difference in the probability of reintubation (p = 0.7). Immediate extubation was associated with longer operating room turnover time (38.4 versus 46.7 minutes; p = 0.009). CONCLUSIONS: Immediate extubation was accomplished in 30.4% of neonates undergoing open heart surgery involving cardiopulmonary bypass. Immediate extubation was associated with lesser ICU LOS, postoperative ICU costs, and minimal increase in operating room turnover time, but without an increase in reintubation rates. Low gestational age, preoperative ventilatory support requirement, and prolonged cardiopulmonary bypass time were inversely associated with the ability to accomplish IE.