Michał Wojtalik

Infection Risk Factors in Pediatric Cardiac Surgery

Cardiac operations were preformed in 499 children from January 1998 through December 1999. Their median age was 263 days. A positive culture from blood, bronchoalveolar lavage, wound, or central catheter was obtained in 110 patients (22%). Age, sex, presence of pulmonary hypertension, body surface area, ratio of body surface area to oxygenator surface area, whether heart surgery was open or closed, and the duration of the operation, cardiopulmonary bypass, intubation, and intensive care were analyzed. Patients who developed infections were significantly younger, with smaller body surface areas and disparity with the oxygenator surface area, longer operative and bypass times, extended intubation, and prolonged intensive care. There was a significant correlation between infection and pulmonary hypertension. Sex and type of operation were not predictors of infection.

Thyroid hormones levels in infants during and after cardiopulmonary bypass with ultrafiltration

OBJECTIVE The aim of this study was to find out if infants after cardiopulmonary bypass develop non-thyroidal illness and if illness severity after cardiopulmonary bypass depends on hormone concentration in ultrafiltrate. METHODS Thyroid hormone status was assessed in 20 infants with congenital heart defects undergoing cardiac surgery (age range 7 days-11 months). Blood samples were collected preoperatively, during cardiopulmonary bypass, after cardiopulmonary bypass, and also postoperatively in 1, 2, 3, and 8 day after cardiac surgery. Plasma thyrotropin, thyroxine, free thyroxine, triiodothyronine, free triiodothyronine and reverse triiodothyronine were measured in blood samples and also in ultrafiltrate. RESULTS All patients had reduction in serum thyrotropin, thyroxine, free thyroxine, triiodothyronine, free triiodothyronine, and elevation of reverse triiodothyronine after cardiac surgery. In all patients we performed ultrafiltration. Patients were divided in to two groups. (with and without prolonged recovery). In the group of patients with prolonged recovery we noticed significantly higher amount of triiodothyronine per kilogram body weight. One of these patients died. The average level of total thyroxine decreased from the level 126 nmol/l before bypass to the minimal level 73 nmol/l after bypass, free thyroxine from the level 18 pmol/l before bypass to the minimal level 12 pmol/l after bypass. The average level of total triiodothyronine decreased from the level 1.54 nmol/l before bypass to the minimal level 0.42 nmol/l after bypass, free triiodothyronine from the level 6.12 pmol/l before bypass to the minimal level 3.21 pmol/l after bypass. The average level of TSH decreased from the level 4.31 mU/l before bypass to the level 0.64 mU/l after bypass. The average level of reverse-triiodothyronine increase from the level 0.83 nmol/l before bypass to the maximal level 1.94 nmol/l after bypass. CONCLUSIONS We conclude that non-thyroidal illness occurs in all infants after cardiopulmonary bypass. The amount of free triiodothyronine that is filtrated during cardiopulmonary bypass may influence postoperative recovery.

Does contegra xenograft implantation evoke cellular immunity in children

The aim of the study was to search for changes in subpopulations of peripheral blood lymphocytes and in their activation as the manifestation of cellular immunity against xenograft in recipients of bovine valved conduit used for right ventricle outflow tract reconstruction. Between 24-06-1999 and 19-10-2000 35 children were operated in ECC, 19 had a xenograft implanted, the rest entered the control group. Immunophenotype of lymphoid cells and T cells activation was evaluated with use of flow cytometer: preoperatively and 3, 6 and 12 months after the operation in both groups. There were no differences in numbers of CD3+, CD4+, CD8+ and natural killer cells between groups. A significant rise of B-cells percentages (from 15.5% to 23%) between 3rd and 6th month was noted. The T-lymphocyte activation study revealed higher numbers of CD69+ (0.17 vs. 0.09 G/l) and CD71+ (0.23 vs. 0.11 G/l) cells one year after the implantation in xenograft recipients. Difference between groups in number of CD69+ and CD71+ cells in 12th month may suggest mild activation (<10%) of these subgroups in xenograft recipients. This data may hint the presence of cellular reactivity. Changes in numbers of B-cells may evidence humoral immunity activation. Influence of these phenomena on graft survival remains to be established.

Mid-term experience with valved bovine jugular vein conduits.

From June 1999 to January 2004, 43 children underwent implantation of a valved bovine jugular vein conduit and correction of complex congenital heart defects. Median age was 1.98 years (range, 11 days – 13.3 years). There were 7 early deaths (16.3%) unrelated to conduit failure or thrombosis. Median follow-up of 36 survivors was 24 months (range, 1–48 months, quartile range, 12–48 months), total follow-up was 78 patient-years. There were 3 late deaths (8.3%) due to infection, pulmonary thromboembolism, and sudden cardiac arrest after re-operation to repair a right ventricular outflow tract aneurysm. There were 2 conduit explantations due to dysfunction and suspected endocarditis. Three patients underwent balloon dilatation of distal stenoses. The mean peak gradient through the pulmonary anastomosis was 15 mm Hg (range, 3–42 mm Hg) among patients free from re-intervention. No severe valve regurgitation was observed. Freedom from re-intervention was 72% at 48 months. This conduit remains a good alternative to homografts. Causes of distal stenosis must be clarified, guidelines for prophylactic anticoagulation must be created, and the role of percutaneous balloon dilatation established.

Outcomes of Continuous Renal Replacement Therapy With Regional Citrate Anticoagulation in Small Children After Cardiac Surgery: Experience and Protocol From a Single Center.

Patients after a cardiac surgery in cardiopulmonary bypass often present an acute kidney failure. Continuous renal replacement therapy (CRRT) is often required. The aim of this study was to present effectiveness and safety of CRRT with regional citrate anticoagulation (RCA‐CRRT) in small children after cardiac surgery. A retrospective analysis was conducted on 15 patients after cardiac surgery and who had RCA‐CRRT performed in 2014. The established protocol was followed. Mean time on the RCA‐CRRT was 192 h 40 min with the circuit mean lifetime of 43 h 33 min. Clotting was found to be a cause of shutdown in 29% of circuits. No severe electrolyte and metabolic disorders were observed. The RCA‐CRRT is a safe procedure for critically ill children with contraindications to the CRRT with heparin anticoagulation. To avoid adverse effects related to metabolic disorders a proper procedure protocol has to be followed.

Evaluation of cardiac muscle microvessel density in children diagnosed with cyanotic heart defects

Angiogenesis is largely an adaptive response to tissue hypoxia, which occurs in a wide variety of situations. Interestingly, the extent of hypoxia-induces angiogenesis in the cardiac muscle of children diagnosed with congenital cyanotic heart defects is not well established. Thus, the aim of this study was to 1) estimate the cardiac muscle microvessel density (MVD) in children diagnosed with cyanotic (study group) and non-cyanotic (control group) heart defects and to 2) evaluate the prognostic significance of MVD value in the development of ventricular dysfunction in the postoperative period. The study group included 42 children diagnosed with cyanotic heart defects. The control group comprised 33 patients with a diagnosis of non-cyanotic heart failure. The collected tissue included cardiac muscle sections from the right atrium and interventricular or interatrial wall during surgical correction of the defect. Immunocytochemistry with monoclonal mouse anti-human antibodies against CD31, CD34 and CD105 was employed to estimate the MVD value. The mean cardiac muscle MVD, defined by CD34 expression, was 596.7 ± 32.6 microvessels per 1 mm² in the study group, which was notsignificantly different from the mean MVD in the control group (461.2 ± 30.5). Interestingly, in non-cyanotic heart defects, an inner area of subendocardial meshwork was estimated to have 75.3 ± 7.0 microvessels per 1 mm², compared to 92.8 ± 10.9 microvessels per 1 mm² (p = 0.0082) in patients with cyanotic heart defects. No significant correlations between MVD value and ventricular dysfunction were found. Cyanotic heart defects resulting in chronic hypoxia might provoke angiogenesis in the subendocardial meshwork of the heart wall. The process seems to be independent of the type of cyanotic heart disease and most likely takes place during antenatal development. A ventricular dysfunction observed in some cases of cyanotic heart defects could not be predicted by the estimation of MVD.

Application of the CardioCel bovine pericardial patch – a preliminary report

Introduction Animal pericardial patches are widely used in adult and pediatric cardiac surgery. A search is ongoing for a new material with optimal surgical properties that will reduce intraoperative bleeding and the occurrence of restenosis, calcification, and pseudoaneurysms in long-term observation. One product of interest is the CardioCel bovine pericardial patch. Aim Evaluation of the short-term results of CardioCel bovine pericardial patch implantation during pediatric cardiac surgery. Material and methods The study included 8 patients who underwent surgical correction of congenital cardiac defects between January 2015 and February 2016. Pericardial patches were used to repair supravalvular aortic stenosis and reconstruct the aortic arch and pulmonary arteries. The age of the patients ranged from 10 days to 14 years. Results There were no hospital deaths. The new material exhibited satisfactory durability and elasticity during surgery, facilitating optimal adaptation of the patch to the patients tissues. No significant bleeding was reported from the suture site. The median duration of follow-up was 58 days. During the follow-up, there were no symptoms of pseudoaneurysm formation, patch thickening, or calcification in the areas where the pericardial patches were implanted. No clinical or laboratory symptoms of infection were observed in locations where the new material was applied. Conclusions Satisfactory surgical properties of the patch were observed intraoperatively. Positive results using the new pericardial patch were obtained in short-term follow-up.

Type of cardioplegic solution as a factor influencing the clinical outcome of open-heart congenital procedures

Introduction Cardioplegia is one of the most important modalities of myocardial protection during heart surgery. Aim To assess the impact of blood cardioplegia on postoperative variables, in comparison with two types of crystalloid cardioplegic solutions during pediatric heart surgery. Material and methods One thousand one hundred and twenty-nine patients underwent surgical correction of congenital heart disease with cardioplegia administration between 2006 and 2012. Nonlinear regression models of postoperative low cardiac output syndrome (LCOS) incidence, catecholamine index and total complication count were developed using a genetic algorithm. The Akaike information criterion was applied for selection of the best model. The following explanatory variables were evaluated: cardioplegia type (ST – Saint Thomas, n = 440; FR – Fresenius, n = 432; BL – Calafiore, n = 257), congenital heart diseases (CHD) type, age, sex, genetic disorder presence, body surface area (BSA), cardiopulmonary bypass (CBP) time, aortic cross-clamp time, operation urgency, redo surgery, surgeon. Results Low cardiac output syndrome presence and higher than average catecholamine indexes were negatively influenced by use of crystalloid cardioplegia (ST or FR), presence of specific CHDs, redo surgery and prolonged CBP time. Increased complication count was related to: crystalloid cardioplegia, presence of specific CHDs, redo surgery, urgency of operation, operation time and CBP time. Higher BSA had a protective effect against higher catecholamine index and increased complication count. Older age was protective against LCOS. Conclusions Cardioplegic solutions type influences postoperative variables in children after heart surgery by the negative impact of crystalloid cardioplegia. Blood cardioplegia presents potential advantages for patients – its application may reduce the incidence of low cardiac output syndrome and related complications.

Late proximal pulmonary artery occlusion in a child with a single chamber after a right-sided Blalock-Taussig shunt.

The paper presents the management of a child born with pulmonary valve atresia, a single (double-inlet) ventricle, right ventricular hypoplasia, and perimembranous septal defect. The first stage of treatment consisted in a Blalock-Taussig shunt. Control angiography performed 1 year after surgery confirmed that the anastomosis was correct, and there was no narrowing at the connection. The first stage of treatment was complicated by the occlusion of the left pulmonary artery, as diagnosed during cardiac catheterization before the planned bidirectional Glenn anastomosis. A decision was made to perform surgery through a left thoracotomy without a cardiopulmonary bypass in order to restore the continuity of the left pulmonary artery.

[Hybrid treatment of interrupted aortic arch in a newborn with contraindications for extracorporeal circulation: case report including 1.5 year follow-up].

Despite marked improvement in the cardiosurgery, total repair of interrupted aortic arch with coexisting risk factors in neonatal or early infancy is associated with high mortality. We present a patient treated by an alternative hybrid procedure without exposing the critical ill neonate to the risk of cardiopulmonary bypass. At the 1.5 year of life a successful arch reconstruction, repair of associated anomalies and de-banding of pulmonary arteries with a stent cut out was done.