Luiz Fernando Caneo

Neonatal and pediatric extracorporeal membrane oxygenation in developing Latin American countries

Objective To review the principles of neonatal-pediatric extracorporeal membrane oxygenation therapy, prognosis, and its establishment in limited resource-limited countries in Latino America.

Pulmonary root translocation in malposition of great arteries repair allows right ventricular outflow tract growth

OBJECTIVE Optimal surgical treatment of patients with transposition of the great arteries (TGA), ventricular septal defect (VSD), and pulmonary stenosis (PS) remains a matter of debate. This study evaluated the clinical outcome and right ventricle outflow tract performance in the long-term follow-up of patients subjected to pulmonary root translocation (PRT) as part of their surgical repair. METHODS From April 1994 to December 2010, we operated on 44 consecutive patients (median age, 11 months). All had malposition of the great arteries as follows: TGA with VSD and PS (n = 33); double-outlet right ventricle with subpulmonary VSD (n = 7); double-outlet right ventricle with atrioventricular septal defect (n = 1); and congenitally corrected TGA with VSD and PS (n = 3). The surgical technique consisted of PRT from the left ventricle to the right ventricle after construction of an intraventricular tunnel that diverted blood flow from the left ventricle to the aorta. RESULTS The mean follow-up time was 72 ± 52.1 months. There were 3 (6.8%) early deaths and 1 (2.3%) late death. Kaplan-Meier survival was 92.8% and reintervention-free survival was 82.9% at 12 years. Repeat echocardiographic data showed nonlinear growth of the pulmonary root and good performance of the valve at 10 years. Only 4 patients required reinterventions owing to right ventricular outflow tract problems. CONCLUSIONS PRT is a good surgical alternative for treatment of patients with TGA complexes, VSD, and PS, with acceptable operative risk, high long-term survivals, and few reinterventions. Most patients had adequate pulmonary root growth and performance.

Modelo experimental de bandagem ajustável do tronco pulmonar para preparo rápido do ventrículo

OBJECTIVE: A device for pulmonary trunk (PT) banding with percutaneous adjustment was developed with the aim of inducing rapid hypertrophy of the subpulmonary ventricle. MATERIAL AND METHODS: It consists of a silicon cuff occluder which holds the pulmonary trunk; an extension tube that connects the cuff to an auto-sealing silicon button, in which water is injected percutaneously to inflate the cuff and adjust the systolic load to the subpulmonary ventricle. The hearts of seven young goats (average wt.: 8.7 kg) were submitted to systolic overload imposed by the device and assessed under hemodynamic, echocardiographic and morphologic aspects. Baseline myocardial samples of the right ventricular outflow tract were harvested for microscopic analysis (perimeter and area of the myocyte). The device was then placed on the PT. The pressures in the right ventricle (RV), PT and aorta were monitored. After convalescence, the protocol of insufflation of the banding device was initiated in order to achieve a RV systolic pressure 70% of the left ventricle systolic pressure. The hemodynamic and echocardiographic evaluations were performed every 24 hours. The RV systolic overload was maintained through a 96 hours period, with gradual insufflations of the cuff every 24 hours, according to the tolerance of the animal to the pressure load. After this period, the animals were killed for morphologic evaluation of the heart. Another nine goats (average wt.: 7.7 kg) were used as control group to compare the ventricle muscle weight. RESULTS: After 96 hours of RV systolic overload, it was observed an increase in systolic gradient RV/PT, from 10.1±4.3 mmHg to 60,0±11,0 mmHg and in the RV systolic pressure, from 22.4±4.1 mmHg to 71.0±10.0 mmHg (p<0.0001). Serial echocardiography showed an increase of the RV thickness, from 4.4±0.5 mm to 7.3±1.7 mm (p=0.001). Regarding RV weight, there was a 74% increase in the RV submitted to the systolic overload, when compared to the control group (p<0.0001). Under optic microscopy, a 27% increase in perimeter and 69% increase in area of the myocytes were observed (p=0.0001). CONCLUSIONS: The device considered in this work is effective and easily adjustable percutaneously, suggesting that the prepare of the subpulmonary ventricle could probably be accomplished in a 96 hour period of systolic overload. Improvements in the adjustment of the PT banding may allow better results of the two-stage Jatene operation in patients with transposition of the great arteries.

Results of the establishment of an organizational model in a cardiovascular surgery service

OBJECTIVE Increasing complexity of patients referred to cardiac surgery demands more effective heart centers, in order to maintain the same quality. The aim of this study is to examine the short-term effect of adoption of an organizational model on surgical outcomes. METHODS From January 2006 to June 2007, 367 consecutive adult patients underwent cardiovascular surgery. Pre-, intra- and postoperative data were prospectively collected and transferred to an institutional database. Organizational model was established in August 2006, and based on integrated multiprofessional team work patient-centered, evidence-based medicine with standardized patient care and personal conflict management. The outcomes studied were hospital mortality and combined adverse events (death, stroke, acute myocardial infarction and acute renal failure), by using multivariate logistic regression analysis. RESULTS After establishment of such model, there was reduction of hospital mortality (from 12% to 3.6%, relative risk= 0.3; P=0.003) and combined events (from 22% to 15%, relative risk=0.68; P=0.11). Operations performed previously to the model were independently associated with higher mortality (OR=2.5; P=0.04), adjusted to preoperative characteristics and Euroscore risk stratification system. Other predictors of mortality were age > 65 years (OR=6.36; 95%CI 2.57 - 17.21; P<0.0001) and cardiopulmonary bypass time > 145 minutes (OR=8.57; 95%CI 3.55 - 21.99; P<0.0001). CONCLUSION Marked improvements in surgical outcomes depend on development of cardiac surgery centers based on organizational models similar to the model proposed in this study.

Emprego do suporte cardiopulmonar com bomba centrífuga e oxigenador de membrana em cirurgia cardiovascular pediátrica

BACKGROUND Extracorporeal membrane oxygenation is a well-documented resuscitation method in patients with severe hemodynamic and/or respiratory impairment. OBJECTIVE To describe several aspects related to the use of extracorporeal membrane oxygenation in a pediatric heart center and determine its immediate and late outcomes. METHODS Between October 2005 and January 2007, 10 patients who were submitted to pediatric cardiac surgery underwent extracorporeal membrane oxygenation implant. Median age was 58.5 days (40% neonates) and median body weight was 3.9 kg. Circulatory assistance was initiated aiming at the recovery and the weaning protocols followed daily clinical and echocardiographic criteria. Support was discontinued when transplant was contraindicated, when the patient was unable to recover or when survival was considered to be limited by a multidisciplinary team. RESULTS Extracorporeal membrane oxygenation was employed after corrective or palliative heart surgery in 80% and preoperatively in the remaining ones. It was most often indicated for irresponsive hemodynamic instability (40%), post-cardiotomy shock (20%) and post-cardiac arrest (20%). The mean duration on support was 58 +/- 37 hours. Weaning was successfully in 50% of the cases and 30% were discharged home. Actuarial survival was 40%, 30% and 20% at 30 days, 3 months and 24 months, respectively. CONCLUSION Extracorporeal membrane oxygenation is an effective and useful tool for the resuscitation of patients presenting severe hemodynamic and/or respiratory failure in the perioperative period of pediatric cardiovascular surgery.

Preparo do ventrículo subpulmonar através de dois diferentes modelos ajustáveis de bandagem do tronco pulmonar: estudo experimental

Two adjustable pulmonary artery banding devices were implanted in 14 young goats to evaluate their efficacy for the training of the pulmonary ventricle (right ventricle). An obstructing balloon catheter was placed in the lumen of the pulmonary artery in 7 animals (group I) and other 7 animals (group II) underwent implantation of an external pulmonary banding device. As a control group for septum, left and right ventricle weights a third group of 7 animals was used. Right ventricle (RV) load was increased gradually, at 24 hours intervals, for 96 hours. RV muscle mass evolution was assessed by echocardiography and by optical microscopy. All animals completed the protocol. RV to PT pressure gradient, RV to LV ratio, and RV systolic pressure were significantly higher in group II (p 0.05). Myocyte perimeter and cross-area increased at the end of the training interval. We concluded that both devices are able to induce a similar degree of pulmonary ventricle hypertrophy, despite higher pressure gradients with the external banding device.

Impaired Pulmonary Function is an Additional Potential Mechanism for the Reduction of Functional Capacity in Clinically Stable Fontan Patients

Central factors negatively affect the functional capacity of Fontan patients (FP), but “non-cardiac” factors, such as pulmonary function, may contribute to their exercise intolerance. We studied the pulmonary function in asymptomatic FP and its correlations with their functional capacity. Pulmonary function and cardiopulmonary exercise tests were performed in a prospective study of 27 FP and 27 healthy controls (HC). Cardiovascular magnetic resonance was used to evaluate the Fontan circulation. The mean age at tests, the mean age at surgery, and the median follow-up time of FP were 20(±6), 8(±3), and 11(8–17) years, respectively. Dominant ventricle ejection fraction was within normal range. The mean of peak VO2 expressed in absolute values (L/min), the relative values to body weight (mL/kg/min), and their predicted values were lower in FP compared with HC: 1.69 (±0.56) vs 2.81 (±0.77) L/min; 29.9 (±6.1) vs 41.5 (±9.3) mL/kg/min p < 0.001 and predicted VO2 Peak [71% (±14) vs 100% (±20) p < 0.001]. The absolute and predicted values of the forced vital capacity (FVC), forced expiratory volume in one second (FEV1), inspiratory capacity (IC), total lung capacity (TLC), diffusion capacity of carbon monoxide of the lung (DLCO), maximum inspiratory pressure (MIP), and sniff nasal inspiratory pressure (SNIP) were also significantly lower in the Fontan population compared to HC. An increased risk of restrictive ventilatory pattern was found in patients with postural deviations (OD:10.0, IC:1.02–97.5, p = 0.042). There was a strong correlation between pulmonary function and absolute peak VO2 [FVC (r = 0.86, p < 0.001); FEV1 (r = 0.83, p < 0.001); IC (r = 0.84, p < 0.001); TLC (r = 0.79, p < 0.001); and DLCO (r = 0.72, p < 0.001). The strength of the inspiratory muscles in absolute and predicted values was also reduced in FP [−79(±28) vs −109(±44) cmH2O (p = 0.004) and 67(±26) vs 89(±36) % (p = 0.016)]. Thus, we concluded that the pulmonary function was impaired in clinically stable Fontan patients and the static and dynamic lung volumes were significantly reduced compared with HC. We also demonstrated a strong correlation between absolute Peak VO2 with the FVC, FEV1, TLC, and DLCO measured by complete pulmonary test.

Post-cardiotomy ECMO in pediatric and congenital heart surgery: impact of team training and equipment in the results.

Introduction Post-cardiotomy myocardial dysfunction requiring mechanical circulatory support occurs in about 0.5% of cases. In our environment, the use of extracorporeal membrane oxygenation has been increasing in recent years. Objective To evaluate the impact of investment in professional training and improvement of equipment in the rate of weaning from extracorporeal membrane oxygenation and survival. Methods A retrospective study. Fifty-six pediatric and/or congenital heart patients underwent post-cardiotomy extracorporeal membrane oxygenation at our institution between November 1999 and July 2014. We divided this period into two phases: phase I, 36 cases (before the structuring of the extracorporeal membrane oxygenation program) and phase II, 20 cases (after the extracorporeal membrane oxygenation program implementation) with investment in training and equipment). Were considered as primary outcomes: extracorporeal membrane oxygenation weaning and survival to hospital discharge. The results in both phases were compared using Chi-square test. To identify the impact of the different variables we used binary logistic regression analysis. Results Groups were comparable. In phase I, 9 patients (25%) were weaned from extracorporeal membrane oxygenation, but only 2 (5.5%) were discharged. In phase II, extracorporeal membrane oxygenation was used in 20 patients, weaning was possible in 17 (85%), with 9 (45%) hospital discharges (P<0.01). When the impact of several variables on discharge and weaning of extracorporeal membrane oxygenation was analyzed, we observe that phase II was an independent predictor of better results (P<0.001) and need for left cavities drainage was associated with worse survival (P=0.045). Conclusion The investment in professional training and improvement of equipment significantly increased extracorporeal membrane oxygenation results.

The economic effect of extracorporeal membrane oxygenation to support adults with severe respiratory failure in Brazil: a hypothetical analysis.

Objective: To analyze the cost-utility of using extracorporeal oxygenation for patients with severe acute respiratory distress syndrome in Brazil. Methods: A decision tree was constructed using databases from previously published studies. Costs were taken from the average price paid by the Brazilian Unified Health System ( Sistema Unico de Saude; SUS) over three months in 2011. Using the data of 10,000,000 simulated patients with predetermined outcomes and costs, an analysis was performed of the ratio between cost increase and years of life gained, adjusted for quality (cost-utility), with survival rates of 40 and 60% for patients using extracorporeal membrane oxygenation. Results: The decision tree resulted in 16 outcomes with different life support techniques. With survival rates of 40 and 60%, respectively, the increased costs were R

A reflection on the performance of pediatric cardiac surgery in the State of São Paulo

=-301.00/-14.00, with a Part of a document submitted to the Brazilian Network for Health Technology Assessment (Rede Brasileira de Avaliacao de Tecnologias em Saude), Ministry of Health. ABSTRACT