Novel inflammatory mediator profile observed during pediatric heart surgery with cardiopulmonary bypass and continuous ultrafiltration.

BACKGROUND: Cardiopulmonary bypass (CPB) is associated with systemic inflammation, featuring increased levels of circulating pro-inflammatory cytokines. Intra-operative ultrafiltration extracts fluid and inflammatory factors potentially dampening inflammation-related organ dysfunction and enhancing post-operative recovery. This study aimed to define the impact of continuous subzero-balance ultrafiltration (SBUF) on circulating levels of major inflammatory mediators. METHODS: Twenty pediatric patients undergoing cardiac surgery, CPB and SBUF were prospectively enrolled. Blood samples were collected prior to CPB initiation (Pre-CPB Plasma) and immediately before weaning off CPB (End-CPB Plasma). Ultrafiltrate effluent samples were also collected at the End-CPB time-point (End-CPB Effluent). The concentrations of thirty-nine inflammatory factors were assessed and sieving coefficients were calculated. RESULTS: A profound increase in inflammatory cytokines and activated complement products were noted in plasma following CBP. Twenty-two inflammatory mediators were detected in the ultrafiltrate effluent. Novel mediators removed by ultrafiltration included cytokines IL1-Ra, IL-2, IL-12, IL-17A, IL-33, TRAIL, GM-CSF, ET-1, and the chemokines CCL2, CCL3, CCL4, CXCL1, CXCL2 and CXCL10. Mediator extraction by SBUF was significantly associated with molecular mass < 66 kDa (Chi2 statistic = 18.8, Chi2 with Yates' correction = 16.0, p < 0.0001). There was a moderate negative linear correlation between molecular mass and sieving coefficient (Spearman R = - 0.45 and p = 0.02). Notably, the anti-inflammatory cytokine IL-10 was not efficiently extracted by SBUF. CONCLUSIONS: CPB is associated with a burden of circulating inflammatory mediators, and SBUF selectively extracts twenty of these pro-inflammatory factors while preserving the key anti-inflammatory regulator IL-10. Ultrafiltration could potentially function as an immunomodulatory therapy during pediatric cardiac surgery. Trial registration ClinicalTrials.gov, NCT05154864. Registered retrospectively on December 13, 2021. https://clinicaltrials.gov/ct2/show/record/NCT05154864 .

Subzero balance - simple modified ultrafiltration (SBUF-SMUF) technique for pediatric cardiopulmonary bypass.

The use of cardiopulmonary bypass (CPB) can be associated with significant hemodilution, coagulopathy and a systemic inflammatory response for infants and children undergoing cardiac surgery. Intra-operative ultrafiltration has been used for decades to ameliorate these harmful effects. The novel combination of a continuous and non-continuous form of ultrafiltration, Subzero Balance Simple Modified Ultrafiltration (SBUF-SMUF) here described, seeks to enhance recovery from pediatric cardiac surgery and CPB.

Sternal cleft reconstruction with acellular dermal matrix and full-thickness calvarial graft.

We describe reconstruction of a sternal cleft in a neonate using acellular dermal matrix, full-thickness calvarial bone graft and myocutaneous pectoralis flaps.

Massive Saddle Pulmonary Embolism in a Preterm Neonate With Successful Emergent Open Embolectomy.

Pulmonary embolism in the neonate is a rare, life-threatening emergency. Risk factors for neonatal pulmonary embolism (PE) include sepsis, asphyxia, prematurity, and vascular catheterisation. We report the case of a preterm neonate with a massive saddle pulmonary thrombosis of unidentified etiology. Prompt diagnosis by cardiology allowed an emergent lifesaving open surgical thrombectomy, underscoring the importance of efficient multidisciplinary teamwork. Pediatric health-care professionals must be aware of this rare entity when initial oxygen desaturation management fails, even when obvious risk factors for PE are not apparent. We emphasise the importance of seamless multidisciplinary communication and proactive surgical consultation.

L'embolie pulmonaire chez le nouveau-né est une urgence rare qui met la vie en danger. Les facteurs de risque d'embolie pulmonaire néonatale comprennent la septicémie, l'asphyxie, la prématurité et le cathétérisme vasculaire. Nous rapportons le cas d'un nouveau-né prématuré présentant une thrombose pulmonaire en selle massive d'origine indéterminée. Un diagnostic rapide par le service de cardiologie a permis la réalisation d'urgence d'une thrombectomie chi-rurgicale ouverte salvatrice, soulignant ainsi l'importance d'un travail d'équipe multidisciplinaire efficace. Les professionnels de la santé en pédiatrie doivent être au fait de cette entité rare lorsque la prise en charge initiale de la désaturation en oxygène échoue, même quand les facteurs de risque évidents d'une embolie pulmonaire ne sont pas apparents. Nous insistons sur l'importance d'une communication multidisciplinaire en continu et d'une consultation chirurgicale proactive.

Psychosocial Distress in Parents with Children Awaiting Surgery during the COVID-19 Pandemic.

Due to resource restrictions related to the COVID-19 pandemic, many pediatric patients are facing substantial delays for surgery, potentially resulting in additional distress for caregivers. We aimed to assess the experiences and psychosocial distress of parents during COVID-19 as they relate to the pandemic, waiting for surgery, and the combined effects of both events. The was a cross-sectional qualitative study. Parents with children who faced treatment delays during the initial wave of the COVID-19 pandemic for elective, non-emergent procedures across a variety of surgical specialties were recruited. Semi-structured telephone interviews and thematic analysis were utilized. Thematic saturation was reached with eighteen participants. Four themes were identified: coping with COVID-19, distress levels, quality and nature of communication with the surgical team, and the experience of COVID-19 related hospital restrictions. Participants reported varying levels of distress due to the delay in surgery, such as the fear of developmental delay or disease progression for their child. They also indicated their own physical and mental health had been impacted by emotional distress related to both COVID-19 and delays in treatment. Most participants experienced the COVID-19-related hospital restrictions as distressing. This related predominantly to limiting in-hospital caregivers to only one caregiver. Participants were found to have substantial levels of psychosocial distress. Targeted social and emotional support may be helpful in reducing parental distress as the pandemic timeframe continues. Within the limits of individual health systems, reducing restrictions to the number of allowed care givers may help allay distress felt by parents.

Silent rupture of sinus of Valsalva aneurysm: a refutation of the Okham's razor principle.

Aneurysm of the sinus of Valsalva is an uncommon congenital lesion rarely reported in children. Unruptured aneurysms commonly go undiagnosed until a rupture has occurred. Usually, ruptured sinus of Valsalva presents with cardiac failure. There may be a history of trauma or infective endocarditis preceding the rupture. Asymptomatic paediatric presentation of ruptured sinus of Valsalva is rare. We discuss the cases of two children who presented with a murmur and were diagnosed with ruptured sinus of Valsalva. This unusual presentation in children highlights the importance of careful routine physical examinations and the evaluation of new murmurs. The Okham's razor principle states that "when you hear hoofbeats - think horses not zebras". Sometimes, it is important to think beyond the usual in medicine, to avoid missing lesions that, if left untreated, could lead to adverse outcomes.

Interprofessional Patient-Specific Simulation Preparation to Improve Management of Neonatal High-Acuity Low-Occurrence (HALO) Scenarios.

Fetal compressive intrapericardial teratoma is a rare and life-threatening condition, qualifying as a high-acuity low-occurrence (HALO) event. To prepare for delivery and immediate neonatal management, specialists from pediatric cardiology, cardiac surgery, maternal-fetal-medicine, neonatology, cardiac anesthesia, critical care, clinical perfusion, obstetrical nursing, and operating room nursing convened. An in situ operating room simulation was used to identify and introduce key team members, derive and practice the anticipated clinical management algorithm, position human and equipment resources strategically, and ensure that each specialist team was familiar with the environment and available equipment. As rehearsed in the simulation, the cesarean delivery of the patient and neonatal cardiac surgery was uncomplicated and yielded a favourable clinical outcome. A patient-specific HALO simulation preparation (PSHSP) can facilitate positive clinical outcomes and improve health care team confidence in HALO scenarios such as the birth of newborns anticipated to have cardiorespiratory instabilty.

Chest wall reconstruction in thoracoabdominal ectopia cordis: using the pedicled osteomuscular latissimus dorsi composite flap.

Ectopia cordis is a rare congenital defect characterized by complete or partial displacement of the heart outside the thoracic cavity. Repair of ectopia cordis can present a reconstructive challenge often requiring a staged approach. Ideally, structural integrity and protection of the heart are restored using autologous tissues capable of growth. In addition, reconstruction of the thorax must proceed without compromise to pulmonary or cardiovascular stability. The following article describes repair of thoracoabdominal ectopia cordis in a patient with pentalogy of Cantrell. Reconstruction of the chest wall was accomplished using a musculoosseus composite flap involving segments of the 9th and 10th ribs and overlying pedicled latissimus dorsi muscle. This is the first report known to the authors of such a repair.

Ultrafiltration in Pediatric Cardiac Surgery Review.

INTRODUCTION: The use of cardiopulmonary bypass in pediatric cardiac surgery is associated with significant inflammation, fluid overload, and end-organ dysfunction yielding morbidity and mortality. For decades, various intraoperative ultrafiltration techniques such as conventional ultrafiltration, modified ultrafiltration (MUF), zero-balance ultrafiltration (ZBUF), and combination techniques (ZBUF-MUF) have been used to mitigate these toxicities and promote improved postoperative outcomes. However, there is currently no consensus on the ultrafiltration technique or strategy that yields the most benefit for infants and children undergoing open heart surgery. METHODS: A librarian-conducted PubMed literature search from 1990 to 2018 yielded 90 clinical studies or publications on the various forms of ultrafiltration and the impact on physiologic markers and clinical outcomes. All publications were reviewed, summarized, and conclusions synthesized. The data sets were not combined for systematic or meta-analysis due to significant heterogeneity in study protocols and patient populations. RESULTS: Modified ultrafiltration significantly promotes improved myocardial function, reduction in fluid overload, and reduced bleeding and transfusion complications. Furthermore, ZBUF has shown a consistent reduction in inflammatory cytokines and improved pulmonary function and compliance. There is conflicting evidence that MUF, ZBUF, and ZBUF-MUF culminate in reduced ventilation time and intensive care unit stay. CONCLUSION: Various modes of ultrafiltration have been shown to be associated with improved physiologic function or clinical outcomes in pediatric cardiac surgery. There are some inconsistent trial results that can be explained by heterogeneity in ultrafiltration, clinical staff preferences, and institution protocols. Ultrafiltration has some essential benefit as it is ubiquitously used at pediatric heart centers; however, the optimal protocol could be yet identified.

Resection of ventricular rhabdomyomas in infants presenting with cardiac failure.

Rhabdomyomas are the most common cardiac tumours in children. They sometimes cause significant obstruction of the ventricular out flow tracts. We report a series of 3 neonates diagnosed antenatally with multiple rhabdomyomas, who developed significant obstruction of the ventricular outflow tracts following birth. They underwent surgical resection in the neonatal period with good outcome. Antenatal diagnosis of obstructive cardiac tumours allows for planning for appropriate early intervention.

Extracardiac Fontan Operation Through a Right Thoracotomy.

An extracardiac Fontan operation through a right thoracotomy incision is an alternative approach in children who have an ascending aorta that is in close proximity to the sternum, as in aortic atresia or transposed great vessels, and in those who have had prior mediastinitis.

Repair of Circumflex Aortic Arch in an Adult.

We describe the diagnoses and repair of a symptomatic circumflex aortic arch in an adult.

Hybrid Stage I Procedure as Initial Palliation for Neonate With Hypoplastic Left Heart Syndrome and Right Congenital Diaphragmatic Hernia.

During the past decade, a hybrid procedure has emerged and dramatically evolved as an alternative stage I palliation to the conventional Norwood procedure in neonates with hypoplastic left heart syndrome (HLHS). The hybrid approach avoids the need for cardiopulmonary bypass (CPB) utilizing stenting of the arterial duct and bilateral pulmonary artery banding. Cerebral and coronary perfusion pressure is maintained, and the pulmonary vasculature is protected from higher systemic pressure. Elimination of risks associated with CPB gains vital time to stabilize the patient and correct coexisting noncardiac anomalies and allows growth in preparation for the later stages of the Fontan pathway. The association of HLHS with right congenital diaphragmatic hernia (CDH) is rare. We report performing a successful hybrid stage I palliation on a neonate with HLHS and severe right CDH.

An alternate technique to pacing in complex congenital heart disease: assessment of the left thoracotomy approach.

BACKGROUND: Pacing in children with congenital heart disease often requires alternate approaches to standard transvenous pacing. The surgical approach used to implant the pacemaker leads has been shown to impact lead survival. There is a paucity of pediatric literature describing the experience using a left thoracotomy approach. OBJECTIVES: To report on short- and mid-term experiences with pacemaker implant via the left thoracotomy approach in children with complex congenital heart disease. METHODS AND RESULTS: Data were abstracted retrospectively from patients' hospital charts. To date, the left thoracotomy technique has been used in 11 patients with complex heart disease, with a median of three prior cardiac operations. The median patient age was five years (range of two months to 23 years of age). The pacing indications were acquired postoperative atrioventricular block (n=5), sinus node dysfunction (n=5) and long QT syndrome (n=1). There were no intraoperative complications or long-term complications from this approach. The pacing thresholds at implant and follow-up were acceptable in all patients. One patient died in follow-up for reasons unrelated to the pacemaker or arrhythmia. CONCLUSIONS: The placement of epicardial pacemaker leads via the left thoracotomy approach is a safe and effective alternative to transvenous pacing in pediatric patients with complex congenital heart disease.

Documenting junctional ectopic tachycardia following pediatric open heart surgery.

OBJECTIVE: To determine appropriated documentations for diagnosis junctional ectopic tachycardia (JET) before treatment in post-operative open heart surgery and identify risk factors for post-operative cardiac arrhythmias in children. MATERIAL AND METHOD: The authors performed a retrospective chart review in 277 patients who underwent surgical corrections at British Columbia's Children Hospital from January 1st, 2000 to December 31st, 2001. History, clinical symptoms, complication of surgery and post-operative cardiac arrhythmias were reviewed from medical records. The authors investigated whether JET was being diagnosed accurately and whether it was being adequately documented prior to the initiation of therapy. The authors also identified risk factors that were associated with JET. All documentations before treatment were reviewed by Pediatric cardiologists to confirm diagnosis. RESULTS: Although the diagnostic accuracy (84%), sensitivity (87%), and specificity (84%) are high, a significant number of patients with post-operative arrhythmias were treated without adequate documentation of the arrhythmia. The documentation of arrhythmias in the Intensive Care Unit was largely limited to rhythm strips, with very few 12-lead ECGs and wire studies performed to assist with the diagnosis. CONCLUSION: The presented data indicates that, in this critically-ill population, there was an unacceptable number of patients with post-operative arrhythmias who may have been treated inappropriately. It is very important to emphasize the interpretation of wire studies, an investigation normally done in a critical care setting and whose interpretation is very important to the accurate diagnosis of pediatric arrhythmias.

Clipped tube fenestration after extracardiac Fontan allows for simple transcatheter coil occlusion.

BACKGROUND: Expensive devices are increasingly used to close a patent fenestration after a modified Fontan operation. We report our 5-year institutional experience of clipped tube fenestration after extracardiac Fontan operation, which allows for simple transcatheter coil occlusion. METHODS: We retrospectively reviewed 30 children, median age of 4.0 years (range, 2.4 to 8.8 years) who underwent extracardiac Fontan operation between May 1996 and May 2001, and were fenestrated using a 4- to 8-mm diameter clipped tube graft. RESULTS: Ten children had a patent fenestration occluded by transcatheter placement of 15 detachable coils (5- to 8-mm diameter). Aortic oxygen saturations increased on average by 5.5% (2% to 14%) and mean pressures in the Fontan circuit by 2.5 mm Hg (0 to 3 mm Hg). Four had immediate complete occlusion angiographically and 6 had trivial residual shunt, but complete occlusion by echocardiography at follow-up. There have been no immediate complications, late coil embolizations, thromboembolic events, or documented hemolysis within a follow-up after coil implantation of 1.7 years (0.4 to 4.5 years). Spontaneous fenestration closure was documented in 8 patients at cardiac catheterization and 9 patients by echocardiography with consistent improvement in resting transcutaneous oxygen saturation. Two children with a patent fenestration have been considered inappropriate for closure, and there was one early surgical death. There have been no complications related to the tube fenestration modification within a follow-up postoperation of 2.6 years (0.1 to 5.5 years). CONCLUSIONS: Clipped tube fenestration after extracardiac Fontan operation is a useful surgical modification that allows for simple transcatheter coil occlusion.

Na+/H+ exchange inhibition with HOE 642 improves recovery of the injured neonatal rabbit heart.

BACKGROUND: The effects of inhibition of the Na+/H+ exchanger (NHE) on postischemic recovery of the injured neonatal rabbit heart were examined. The NHE may be an important mechanism for reperfusion injury in the neonate heart. The effects of two NHE inhibitors, HOE 642 (HOE) and 5-(N,N-dimethyl)-amiloride (DMA), given during hypothermic cardioplegic arrest, were evaluated. METHODS: Isolated working crystalloid-perfused neonatal rabbit hearts were subjected to 10 min of normothermic ischemia to cause injury before undergoing 4 h of hypothermic (10 degrees C) cardioplegic arrest with a single dose of crystalloid solution (controls, n=21) or with the addition of 0.5 micromol/L HOE (n=24) or 30 micromol/L DMA (n=15). RESULTS: Hearts subjected to HOE had improved recoveries of aortic flow when compared with controls at 15 min and 30 min of reperfusion (35.7+/-1.3 mL/min versus 26.2+/-1.4 mL/min, respectively, at 15 min, P<0.0001; 36.5+/-1.5 mL/min versus 23.6+/-1.6 mL/min, respectively, at 30 min, P<0.0001) and with DMA at 30 min (36.5+/-1.5 mL/min versus 29.9+/-1.9 mL/min, P=0.0214). Cardiac output and systolic pressure were also improved at 30 min in HOE hearts versus controls (P<0.0001). CONCLUSIONS: NHE inhibition with HOE during cardioplegic arrest resulted in improved functional recovery of injured hearts. Further studies in blood-perfused neonatal preparations are warranted.

Associated inflammation or increased flow-mediated shear stress, but not pressure alone, disrupts endothelial caveolin-1 in infants with pulmonary hypertension.

Endothelial caveolin-1 loss is an important feature of pulmonary hypertension (PH); the rescue of caveolin-1 abrogates experimental PH. Recent studies in human PH suggest that the endothelial caveolin-1 loss is followed by an enhanced expression of caveolin-1 in smooth muscle cells (SMC) with subsequent neointima formation. In order to evaluate caveolin-1 expression in infants with PH, we examined the available clinical histories, hemodynamic data, and the expression of caveolin-1, PECAM-1, vWF, and smooth muscle α-actin in the lung biopsy/autopsy specimens obtained from infants with congenital heart disease (CHD, n = 8) and lung disease (n = 9). In CHD group, PH associated with increased pulmonary blood flow exhibited loss of endothelial caveolin-1 and PECAM-1 in pulmonary arteries; additional vWF loss was associated with enhanced expression of caveolin-1 in SMC. In the absence of PH, increased or decreased pulmonary blood flow did not disrupt endothelial caveolin-1, PECAM-1, or vWF; nor was there any enhanced expression of caveolin-1 in SMC. In Lung Disease + PH group, caveolin-1, PECAM-1, and vWF were well preserved in seven infants, and importantly, SMC in these arteries did not exhibit enhanced caveolin-1 expression. Two infants with associated inflammatory disease exhibited loss of endothelial caveolin-1 and PECAM-1; additional loss of vWF was accompanied by enhanced expression of caveolin-1 in SMC. Thus, associated flow-induced shear stress or inflammation, but not elevated pulmonary artery pressure alone, disrupts endothelial caveolin-1. Subsequent vWF loss, indicative of extensive endothelial damage is associated with enhanced expression of caveolin-1 in SMC, which may worsen the disease.

Does troponin-I measurement predict low cardiac output syndrome following cardiac surgery in children?

OBJECTIVE: To determine whether serum troponin I (TnI), measured 4 hours after surgery for congenital heart disease, is a predictor of myocardial dysfunction and low cardiac output syndrome (LCOS). DESIGN: Prospective, observational study. SETTING: Paediatric intensive care unit in a tertiary care academic children's hospital, 1 June 2003 to 12 May 2004. PATIENTS: 99 consecutive eligible children who underwent a variety of surgical procedures for congenital heart disease, using cardiopulmonary bypass. All patients were cared for by a consistent perioperative care team. INTERVENTIONS: Measurement of TnI preoperatively, and at 0, 4, 8, 12, 24 and 36 hours after ICU admission. RESULTS: Patient demographics and outcome (as median and 25th-75th percentile) were as follows: age, 23.9 (4.6- 65.9) months; cardiopulmonary bypass time, 135 (98-178) minutes; aortic cross-clamp time, 65 (28-85) minutes; preoperative TnI level, 0.02 (0.01-0.03) ng/mL; 4h TnI, 10.6 (3.0-23.4) ng/mL; highest 24 h TnI, 11.7 (3.9-29.5) ng/mL; time to discontinuation of inotropes, 43.9 (18.7-92.9) hours; maximal inotrope score, 10.0 (5.0-16.3); time to extubation, 42.4 (19.8-137.5) hours; and time to ICU discharge 91.8 (45.7-169.7) hours. Twenty-three patients developed LCOS. A 4h TnI level > 13 ng/mL predicted LCOS with a sensitivity of 0.78 (95% CI, 0.56-0.93), and a specificity of 0.72 (95% CI, 0.61-0.82). The area under the receiver operating characteristic curve for TnI as a predictor of LCOS was 0.75 (95% CI, 0.63-0.88). TnI was the only predictive variable associated with LCOS in multivariate logistic regression analysis, with an odds ratio of 1.45 (95% CI, 1.05-2.01) for developing LCOS with each 10 ng/mL increase in 4h TnI. Linear regression analysis showed TnI to be significantly correlated with increased time to discontinuation of inotropes, maximal inotrope administration, time to extubation, and time to ICU discharge. CONCLUSIONS: Measurement of early postoperative levels of TnI may aid in the early identification of children who will develop LCOS.

Could we still improve early and interim outcome after prosthetic systemic-pulmonary shunt? A risk factors analysis.

OBJECTIVE: To identify factors associated with in-hospital and interim mortality in children with a systemic-to-pulmonary shunt (SPS). METHODS: Between January 1988 and April 2005, 226 children with a median age of 17 days, and weight of 3.4 kg, underwent an isolated SPS for pulmonary atresia (PA)-VSD/ tetralogy (n=124, 54.9%), functional single ventricle PA (n=35, 5.5%), PA-intact septum (IS, n=31, 13.7%), transposition of the great arteries VSD-PA (n=30, 13.3%), and double outlet right ventricle-PA (n=6, 2.6%). Surgery was performed through sternotomy (group S, n=46) or thoracotomy (group T, n=180). The origin of the SPS was either the innominate artery (n=38) or ascending aorta (n=8) in group S, and the subclavian artery (n=180) in group T. RESULTS: In-hospital mortality was 5.7%. Univariate and logistic regression analysis revealed younger age (p=0.01), lower body weight (p<0.04), a diagnosis of PA-IS with severe right ventricle hypoplasia (p=0.005), preoperative intubation (p=0.03), increased length of intubation (p<0.0001), longer ICU stay (p<0.0001), and group S (p=0.03) as risk factors for in-hospital death. Group S had a longer median ventilation time (112 vs 30 h, p<0.0001) despite the similar median age, weight, mean indexed shunt size (1.19 vs 1.15 mm/kg, p=0.2), and the number of patients with antegrade pulmonary flow. Interim mortality was 7% (n=15), and younger age (p=0.03), and group T (p=0.03) were independent risk factors for death prior to second-stage surgery. Absence of antiplatelet agents or anticoagulants was not a risk factor for interim mortality. CONCLUSIONS: In-hospital mortality and longer ventilation time after SPS by sternotomy may be related to pulmonary over circulation due to shunt insertion origin and/or size, and pathologic features. Early and interim outcomes can be improved by using a smaller shunt or changing the SPS insertion origin when using a sternotomy approach.