Prolonged cardiopulmonary resuscitation and low flow state are not contraindications for extracorporeal support.

Outcomes of out-of-hospital cardiac arrest are poor irrespective of the patient age group and circumstances. Survival to discharge after out-of-hospital arrest in children is less than 10%. Use of extracorporeal cardiopulmonary resuscitation is increasing and has been shown to improve outcomes in some situations. However, the candidacy for such augmentation is based on patient selection, institutional practices, and availability of an extracorporeal membrane oxygenation center. Often, duration of resuscitation, low flow state, presenting pH, and circumstances of arrest dictate candidacy for extracorporeal membrane oxygenation. We present a case of extremely prolonged resuscitation for out-of-hospital arrest in a pediatric patient, and we describe the use of mechanical compression device and transition to extracorporeal membrane oxygenation. We present the case outcome as well as brief discussion about controversies in extracorporeal cardiopulmonary resuscitation. We hope the case provides an opportunity for further discussion regarding opportunities to improve selection, use of extracorporeal cardiopulmonary resuscitation, and impact outcomes.

Polymyxin B for Gram Negative Multidrug Resistant Bacteria in a Hispanic Population.

OBJECTIVE: This study intends to determine the prevalence of multidrug resistant (MDR) infections by A. baumannii, K. pneumoniae and P. aeruginosa in a tertiary care teaching hospital intensive care unit (ICU) in San Juan, PR, estimate the mortality rate and compare the morbidity and mortality differences among those treated with and without polymyxin B. METHODS: We selected adults patients admitted to the ICU who had positive cultures from January 2012 to June 2013. Sample consisted of 25 patients with age ranges from 27-78 years, 13 women and 12 men. RESULTS: The median age at death was 60 years. Polymyxin B nephrotoxicity was identified on 15% of the patients. Variables related to higher survival were younger age, female sex, use of polymyxin B, and the use of daptomycin. The use of vancomycin and vasopressors were associated with worse outcome. Mortality associated to single MDR bacteria was 88% for A. baumannii, 84% for K. pneumoniae and 67% for P. aeruginosa. All patients with more than one MDR infection died in the ICU. CONCLUSION: The use of polymyxin B was associated with an ICU mortality reduction. Unexpectedly we found a significantly improved survival in patients who received polymyxin B in combination with daptomycin, which awaits prospective confirmation.

Idiopathic infantile arterial calcification: a case report of successful extracorporeal membrane oxygenation support.

Idiopathic infantile arterial calcification is a rare cause of infantile ischemic cardiac failure with extremely poor prognosis. We present the first case report of successful extracorporeal membrane oxygenation support and outcome in a child with idiopathic infantile arterial calcification (IIAC). This 6-week-old infant presented with cardiogenic shock and circulatory collapse. The patient underwent extracorporeal cardiopulmonary resuscitation, allowing stabilization, diagnosis, and treatment with etidronate, followed by successful discharge to home.

Low-weight infants are at increased mortality risk after palliative or corrective cardiac surgery.

BACKGROUND: Low weight is an established risk factor for mortality after congenital cardiac surgery. Given the advances in the care of neonates and infants after surgery, we sought to examine the effect of low weight on outcomes in the current era. METHODS: From 2002 to 2012, 2051 infants aged 90 days or less underwent cardiac surgery including 534 (26.0%) with single-ventricle pathology. Regression models examined the effect of low weight (≤ 2.5 kg; n = 274, 13.4%) on early and late outcomes. RESULTS: Overall, the incidence of prematurity, associated chromosomal/extracardiac abnormalities was higher in infants who weighed 2.5 kg or less than in those who weighed more than 2.5 kg; the incidence of single-ventricle pathology was comparable between the 2 groups. In addition, infants who weighed 2.5 kg or less underwent more palliation and had a higher proportion of STAT (Society of Thoracic Surgeons-European Association for Cardio-Thoracic Surgery) risk category 4 and 5 procedures. Adjusted regression models showed that low weight (≤ 2.5 kg) did not increase unplanned reoperation (odds ratio [OR], 0.90; 95% confidence interval [CI], 0.48-1.67; P = .73) or extracorporeal membrane oxygenation requirement (OR, 1.23; 95% CI, 0.68-2.22; P = .49), however it was associated with significant increase in hospital mortality (OR, 2.15; 95% CI, 1.33-3.50; P = .002). In addition, there was a significant association between low weight and increased duration of postoperative mechanical ventilation and intensive care unit and hospital stays. Adjusted hazard analysis showed that weight equal to or less than 2.5 kg was associated with diminished late survival (hazard ratio, 1.89; 95% CI, 1.39-2.55; P < .001) and that was evident in all patients subgroups (P < .001 for all). CONCLUSIONS: In a large single-center series, low weight continues to be associated with increased early mortality risk and resource utilization after palliative and corrective cardiac surgery. The hazard of death in low-weight patients continues beyond the perioperative period for at least 1 year before normalizing. Strategies to improve outcomes for this high-risk population must address perioperative care, outpatient surveillance, and management.

Flexible single-incision surgery: a fusion technique.

INTRODUCTION: The development of natural orifice transluminal endoscopic surgery has led to other techniques, such as single-incision surgery. The use of the flexible endoscope for single-incision surgery paves the way for further refinement of both surgical methods. OBJECTIVE: To describe a new, single-incision surgical technique, namely, flexible single-incision surgery. PATIENTS AND METHODS: Assessment of the safety and effectiveness of endoscopic cholecystectomy in a series of 30 patients. This technique consists of a single umbilical incision through which a flexible endoscope is introduced and consists of 2 parallel entry ports that provide access to nonarticulated laparoscopic instruments. RESULTS: The technique was applied in all patients for whom it was prescribed. No general or surgical wound complications were noted. Surgical time was no longer than usual for single-port surgery. CONCLUSIONS: Flexible single-incision surgery is a new single-site surgical technique offering the same level of patient safety, with additional advantages for the surgeon at minimal cost.

Integración del endoscopio flexible en cirugía digestiva / Incorporation of the flexible endoscope in gastrointestinal surgery

El endoscopio flexible no ha figurado tradicionalmente entre el conjunto de dispositivos manejados por el cirujano digestivo. La endoscopia flexible intraoperatoria puede ser una de las técnicas que en un futuro no lejano estén disponibles en el quirófano de manera habitual. Al analizar el desarrollo de la cirugía mínimamente invasiva y de la endoscopia flexible, nos damos cuenta de cómo estamos convergiendo y de cómo podemos ir cediendo terreno a la endoscopia digestiva por un lado y ganándolo, con el endoscopio flexible, por otro. El desarrollo de las técnicas «híbridas» NOTES nos ha enseñado a mirar como potencialmente útiles en el quirófano equipos que no son habituales en nuestro entorno. La endoscopia flexible es probablemente la técnica que ofrece mayor rentabilidad al incorporarse al área quirúrgica. Es necesaria la colaboración estrecha con los digestólogos endoscopistas, a la vez que vamos formando a los cirujanos en este tipo de técnicas para un futuro de especialistas «híbridos» (AU)

The flexible endoscope has not traditionally figured among the tools used by the surgeon. Intra-operative flexible endoscopy may be one of the techniques available in the operating room in the near future. On analysing the development of minimally invasive surgery and flexible endoscopy, it can be seen that they are converging and losing ground to gastrointestinal endoscopy on the one hand, and gaining it with the flexible endoscope, on the other. The technical development of «hybrid» NOTES has shown how some tools not usually available in theatre may bevery useful. Flexible endoscopy is probably the technique to enter into the surgical area that offers improved performance. Surgeons need to work closely with the gastroenterologists, while they are trained in these techniques for future «hybrid» specialists (AU)

Prospective randomized clinical trial comparing laparoscopic cholecystectomy and hybrid natural orifice transluminal endoscopic surgery (NOTES) (NCT00835250).

BACKGROUND AND STUDY AIMS: Natural orifice transluminal endoscopic surgery (NOTES) is a technique still in experimental development whose safety and effectiveness call for assessment through clinical trials. In this paper we present a three-arm, noninferiority, prospective randomized clinical trial of 1 year duration comparing the vaginal and transumbilical approaches for transluminal endoscopic surgery with the conventional laparoscopic approach for elective cholecystectomy. PATIENTS AND METHODS: Sixty female patients between the ages of 18 and 65 years who were eligible for elective cholecystectomy were randomized in a ratio of 1:1:1 to receive hybrid transvaginal NOTES (TV group), hybrid transumbilical NOTES (TU group) or conventional laparoscopy (CL group). The main study variable was parietal complications (wound infection, bleeding, and eventration). The analysis was by intention to treat, and losses were not replaced. RESULTS: Cholecystectomy was successfully performed on 94% of the patients. One patient in the TU group was reconverted to CL owing to difficulty in maneuvering the endoscope. After a minimum follow-up period of 1 year, no differences were noted in the rate of parietal complications. Postoperative pain, length of hospital stay, and time off from work were similar in the three groups. No patient developed dyspareunia. Surgical time was longer among cases in which a flexible endoscope was used (CL, 47.04 min; TV, 64.85 min; TU, 59.80 min). CONCLUSIONS: NOTES approaches using the flexible endoscope are not inferior in safety or effectiveness to conventional laparoscopy. The transumbilical approach with flexible endoscope is as effective and safe as the transvaginal approach and is a promising, single-incision approach.

NOTES, MANOS, SILS and other new laparoendoscopic techniques.

A new way of opening a body cavity can be a revolution in surgery. In 1980s, laparoscopy changed how surgeons had been working for years. Natural orifice translumenal endoscopic surgery (NOTES), minilaparoscopy-assisted natural orifice surgery (MANOS), single incision laparoscopic surgery (SILS) and other new techniques are the new paradigm in our way of operating in the 21(st) century. The development of these techniques began in the late 90s but they have not had enough impact to develop and evolve. Parallels between the first years of laparoscopy and NOTES can be made. Working for an invisible surgery, not only for cosmesis but for a less invasive surgery, is the target of NOTES, MANOS and SILS performed by surgeons and endoscopists over the last 10 years. The future flexible endoscopic platforms and the fusion between laparoscopic instruments and devices and robotic surgery will be a great advance for "scarless surgery".

[Incorporation of the flexible endoscope in gastrointestinal surgery]. / Integración del endoscopio flexible en cirugía digestiva.

The flexible endoscope has not traditionally figured among the tools used by the surgeon. Intra-operative flexible endoscopy may be one of the techniques available in the operating room in the near future. On analysing the development of minimally invasive surgery and flexible endoscopy, it can be seen that they are converging and losing ground to gastrointestinal endoscopy on the one hand, and gaining it with the flexible endoscope, on the other. The technical development of «hybrid¼ NOTES has shown how some tools not usually available in theatre may be very useful. Flexible endoscopy is probably the technique to enter into the surgical area that offers improved performance. Surgeons need to work closely with the gastroenterologists, while they are trained in these techniques for future «hybrid¼ specialists.

Short-term outcomes in premature neonates adhering to the philosophy of supportive care allowing for weight gain and organ maturation prior to cardiac surgery.

BACKGROUND: Prematurity is a recognized risk factor for morbidity and mortality following cardiac surgery. The purpose of this study was to examine short-term outcomes following cardiac surgery in premature neonates adhering to our institutional philosophy of supportive care allowing for weight gain and organ maturation. METHODS: Retrospective review of all neonates undergoing cardiac surgery from January 2002 to May 2008. A total of 810 neonates (<30 days of age) were identified. Prematurity defined as less than 36 weeks of gestation. Neonates undergoing ductus arteriosus ligation alone were excluded. In all, 63 neonates comprised the premature group. Term group comprised 244 randomly selected term neonates in a 1:4 ratio. Outcome variables were compared between the 2 groups. RESULTS: Median gestation 34 weeks, range 24 to 35 weeks. Defects: 2 ventricle, normal arch (41% premature vs 44% term; P = .7), 2 ventricle, abnormal arch (24% vs 22%; P = .8), single ventricle, normal arch (21% vs 15%; P = .2), single ventricle, abnormal arch (14% vs 19%; P = .4). Premature neonates were older and smaller at surgery. Cardiopulmonary bypass procedures were performed less frequently in premature neonates (49% vs 69%; P = .004). Length of mechanical ventilation at our institution (6 days [0.5-54) vs 4 days [0.5-49); P = .06); postoperative hospital stay at our institution (17 days [1-161) vs 15 days [0-153); P = .06); and mortality (16% vs 11%; P = .2) was not different between the 2 groups. CONCLUSION: Early outcome seems independent of weight, prematurity, cardiopulmonary bypass, and type of first intervention. Importantly, there was no statistical difference in mortality between the 2 groups, regardless of how they were treated. Further long-term follow-up is needed in this patient population.

Do neonates with genetic abnormalities have an increased morbidity and mortality following cardiac surgery?

INTRODUCTION: Genetic abnormalities occur in approximately 20% of children with congenital heart disease. The purpose of this study was to evaluate the effect of genetic abnormalities on short-term outcomes following neonatal cardiac surgery. METHODS: Retrospective review of all neonates (n = 609) undergoing cardiac surgery from January 2003 to December 2006. Genetic abnormalities were identified in 93 neonates (15%). Genetic abnormalities identified were 22q11.2 deletion (23), chromosomal abnormalities including various monosomies, trisomies, deletions, duplications, and inversions (17), dysmorphic undefined syndrome without recognized chromosomal abnormality (27), Down syndrome (9), laterality sequences (9), recognixed syndromes and genetic etiology including Mendelian (i.e. Alagille, CHARGE) (8). RESULTS: Neonates with genetic abnormalities had lower birth weights and were older at time of surgery. There was no difference in operative variables, duration of mechanical ventilation or ICU length of stay between the two groups. There was an increase in total hospital length of stay and postoperative complications in the neonates with genetic abnormalities. Importantly, in hospital mortality was not different. CONCLUSION: Neonates with genetic abnormalities have a higher risk of postoperative complications and a longer hospital length of stay. However, there is no increase in hospital mortality. This information may aid in patient management decisions and parental counseling. Longer-term studies are needed for understanding the total impact of genetic abnormalities on neonates with congenital heart disease.

Estudio comparativo, prospectivo y no aleatorizado de la colecistectomía endoscópica transvaginal frente a la colecistectomía laparoscópica transparietal / Non-randomised, comparative, prospective study of transvaginal endoscopic cholecystectomy versus transparietal laparoscopic cholecystectomy

Introducción: Presentamos un estudio comparativo no aleatorizado de dos series seguidas de manera prospectiva en las que se compara la colecistectomía laparoscópica convencional con la colecistectomía transvaginal, procedimiento endoscópico transluminal híbrido, con el objetivo de valorar la seguridad clínica del procedimiento y su eficacia en la resolución de la colelitiasis. Pacientes y método: Serie clínica prospectiva no aleatorizada de 40 mujeres intervenidas por colelitiasis mediante cirugía endoscópica, 20 con abordaje laparoscópico convencional y 20 mediante abordaje endoscópico transvaginal. Se analizaron como variables la infección de herida quirúrgica, la infección urinaria, la evisceración, la eventración, la mortalidad y otras complicaciones. Resultados: Se realizó la intervención prevista en las 40 pacientes a quienes se indicó. No hubo complicaciones intraoperatorias. No hubo ningún caso de mortalidad relacionada con los procedimientos y sólo se produjo una complicación postoperatoria, infección del tracto urinario, en una paciente operada por vía transvaginal. El seguimiento medio ha sido el mismo en ambos grupos (9 meses). La estancia media fue en ambos grupos<0,8 días. La duración de la cirugía fue mayor en el grupo con abordaje transvaginal, con 69,5min de media frente a 46,2min en el grupo laparoscópico. Conclusiones: Si bien la ventaja estética es patente, en esta serie no se han encontrado diferencias en relación con problemas parietales. La duración de la cirugía transvaginal es mayor que la de la transparietal, pero los tiempos medios de ambas son aceptables. En este estudio se puede valorar la no inferioridad en eficacia y seguridad del abordaje transvaginal(AU)

Introduction: We present a non-randomised comparative study of two patients series followed up prospectively, in which convention laparoscopic cholecystectomy is compared with transvaginal cholecystectomy, a hybrid transluminal endoscopic procedure, with the objective of assessing the clinical safety of the procedures and its efficacy in the resolution of cholelithiasis. Patients and method: A non-randomised prospective clinical series of 40 female patients, operated on for cholelithiasis using endoscopic surgery, 20 with a conventional laparoscopic approach and 20 using a transvaginal endoscopic approach. Surgical wound infection, urinary infection, evisceration, eventration, mortality and other complications. Results: Scheduled operations were performed on the 40 patients as indicated. There were no complications during the operations. There was no mortality associated with the procedures and there was only one post-surgical complication, a urinary tract infection in one patient operated on by the transvaginal approach. The mean follow up was the same in both groups (9 months). The mean hospital stay was less than 0.8 days in both groups. The duration of the surgery was longer in the transvaginal approach group, with a mean of 69.5min, compared to 46.2min in the laparoscopy group. Conclusions: Although the cosmetic benefit is obvious, no differences were found as regards parietal problems in this series. The duration of the transvaginal surgery is higher than that of the transparietal, but the times of both are acceptable. In this study, the non-inferiority in the safety and efficacy of the transvaginal approach is able to be assessed(AU)

[Non-randomised, comparative, prospective study of transvaginal endoscopic cholecystectomy versus transparietal laparoscopic cholecystectomy]. / Estudio comparativo, prospectivo y no aleatorizado de la colecistectomía endoscópica transvaginal frente a la colecistectomía laparoscópica transparietal.

INTRODUCTION: We present a non-randomised comparative study of two patients series followed up prospectively, in which convention laparoscopic cholecystectomy is compared with transvaginal cholecystectomy, a hybrid transluminal endoscopic procedure, with the objective of assessing the clinical safety of the procedures and its efficacy in the resolution of cholelithiasis. PATIENTS AND METHOD: A non-randomised prospective clinical series of 40 female patients, operated on for cholelithiasis using endoscopic surgery, 20 with a conventional laparoscopic approach and 20 using a transvaginal endoscopic approach. Surgical wound infection, urinary infection, evisceration, eventration, mortality and other complications. RESULTS: Scheduled operations were performed on the 40 patients as indicated. There were no complications during the operations. There was no mortality associated with the procedures and there was only one post-surgical complication, a urinary tract infection in one patient operated on by the transvaginal approach. The mean follow up was the same in both groups (9 months). The mean hospital stay was less than 0.8 days in both groups. The duration of the surgery was longer in the transvaginal approach group, with a mean of 69.5 min, compared to 46.2 min in the laparoscopy group. CONCLUSIONS: Although the cosmetic benefit is obvious, no differences were found as regards parietal problems in this series. The duration of the transvaginal surgery is higher than that of the transparietal, but the times of both are acceptable. In this study, the non-inferiority in the safety and efficacy of the transvaginal approach is able to be assessed.

Hybrid transvaginal cholecystectomy, NOTES, and minilaparoscopy: analysis of a prospective clinical series.

INTRODUCTION: Natural orifice transluminal endoscopic surgery (NOTES) makes it possible to perform intraperitoneal surgical procedures with a minimal number of access points in the abdominal wall. It is not yet possible to perform these interventions without the help of abdominal wall entryways, so these procedures are hybrids, a fusion of minilaparoscopy and transluminal endoscopic surgery. In this paper we present a prospective clinical series of 15 patients who underwent transvaginal hybrid cholecystectomy for cholelithiasis. METHODS: This was a prospective clinical series of 15 consecutive female patients, nonrandomly chosen and without a control group, who underwent a fusion transvaginal NOTES and minilaparoscopy procedure with two entryways for cholelithiasis. One was umbilical and measured 5 mm in diameter, and the other was in the right upper quadrant and measured 3 mm in diameter. RESULTS: The scheduled surgical intervention was performed on the 15 patients in whom it had been indicated. There were no intraoperative complications. One patient had mild hematuria that resolved in less than 12 h; there were no other complications after average follow-up of 124 days. Nine patients were discharged in 24 h, and two were discharged less than 12 h after the procedure. DISCUSSION: Hybrid transvaginal cholecystectomy is a good surgical model for minimally invasive surgery, a combination of NOTES and minilaparoscopy. It can be performed in surgical settings where laparoscopy is practised regularly, using the instruments normally used for endoscopy and laparoscopic surgery. Owing to the reproducibility of the intervention and the ease of vaginal closure, hybrid transvaginal cholecystectomy will permit further development of NOTES in the future.

Hemodynamic effects and safety of nesiritide in neonates with heart failure.

OBJECTIVE: Evaluate effects and safety of nesiritide (Natrecor, Scios Inc.) human B-type natriuretic peptide, in neonates with heart failure. METHODS: Seventeen neonates, not responding to conventional therapy, treated with nesiritide were retrospectively reviewed. RESULTS: Average age 16 + 8 days; weight 3.2 + 0.6 kg. Fifteen treated with concomitant inotropic therapy; all with diuretics. Twelve received loading dose; followed by continuous infusions of 0.005 mcg/kg/min (2); 0.01 mcg/kg/min (12); 0.02 mcg/kg/min (3). Length of therapy 5 + 4 days. No change in heart rate or blood pressure between baseline, 1 hour or 24 hours of nesiritide infusion. Decrease central venous pressure (CVP) 24 hours after infusion (p = 0.03). Ins-out ratio improved in 29%. No difference in pre and post therapy BUN and creatinine (Cr). 18% had hypotension requiring intervention. CONCLUSIONS: Nesiritide use in neonates may improve hemodynamics as demonstrated by reduction in CVP. All patients tolerated bolus dosing, however, transient hypotension occurred in 18% of neonates with continuous infusion.

B-type natriuretic peptide in the emergency diagnosis of critical heart disease in children.

OBJECTIVE: The initial presentation of congenital and acquired heart disease in children can present a diagnostic challenge. We sought to evaluate B-type natriuretic peptide as a marker of critical heart disease in children at presentation in the acute care setting. METHODS: A cohort of 33 pediatric patients with newly diagnosed congenital or acquired heart disease had B-type natriuretic peptide levels obtained on hospital admission after evaluation in an acute care setting. Patients were admitted from March 2005 through February 2007. A noncardiac cohort of 70 pediatric patients who presented with respiratory or infectious complaints had B-type natriuretic peptide levels obtained during emergency department evaluation. A comparison of B-type natriuretic peptide results was performed. RESULTS: Cardiac diagnoses included cardiomyopathy (14), left-sided obstructive lesions (12), anomalous left coronary artery from the pulmonary artery (4), total anomalous pulmonary venous return (2), and patent ductus arteriosus (1). Cardiac cohort mean age at presentation was 33.6 months. The 33 patients with new cardiac diagnoses had a mean B-type natriuretic peptide level of 3290 pg/mL (SD: +/-1609; range: 521 to >5000 pg/mL). The 70 noncardiac patients' mean age at presentation was 23.1 month, and mean B-type natriuretic peptide level was 17.4 pg/mL (SD: +/-20; range: <5 to 174 pg/mL). CONCLUSIONS: B-type natriuretic peptide levels were markedly elevated at presentation in the acute care setting for all patients in this cohort of children with newly diagnosed congenital or acquired heart disease. B-type natriuretic peptide levels from noncardiac patients were significantly lower, with no overlap to the cardiac disease group. B-type natriuretic peptide level can be useful as a diagnostic marker to aid in the recognition of pediatric critical heart disease in the acute care setting.

Does preoperative mechanical ventilation affect outcomes in neonates undergoing cardiac surgery?

OBJECTIVE: To review, in retrospective fashion, the effect of preoperative mechanical ventilation on neonatal outcomes after cardiac surgery. METHODS: We studied 114 newborns less than 15 days old admitted to the cardiac intensive care unit for cardiac surgery. Of the newborns, 71 (62%) were mechanically ventilated at the referring hospital before transport to our institution. Of the 71 ventilated patients, 14 were extubated and breathing spontaneously before cardiac surgery. We compared variable haemodynamics and outcomes between the 57 patients mechanically ventilated at time of cardiac surgery, and the 57 patients breathing spontaneously at this time. RESULTS: Newborns mechanically ventilated before cardiac surgery had increased preoperative haemodynamic compromise, increased postoperative sepsis (p equal to 0.02) and mortality (p equal to 0.005) compared with those breathing spontaneously before cardiac surgery. CONCLUSION: Newborns requiring preoperative mechanical ventilation had greater risk of postoperative morbidity and mortality. Heightened vigilance is warranted in this population of patients at high risk.

Risk adjustment for congenital heart surgery (RACHS): is it useful in a single-center series of newborns as a predictor of outcome in a high-risk population?

OBJECTIVE: Risk adjustment for congenital heart surgery (RACHS) was developed to compare outcome data for pediatric patients undergoing cardiac surgery. RACHS stratifies anatomic diversity into 6 categories based on age, type of surgery performed, and similar in-hospital mortality. The purpose of this retrospective review was to evaluate the use of RACHS in a single-center series as a predictor of outcome in a high-risk newborn population. METHODS: In 2003, 793 pediatric cardiac surgical operations (584 open; 209 closed) were performed at our institution. Mortality was 2.1%. Of the 793 operations, 114 were in newborns less than 15 days of age. These 114 newborns were stratified according to RACHS. Two patients could not be stratified and were excluded from analysis. Preoperative, operative, and postoperative variables were compared between the RACHS stratified newborns. RESULTS: Unexpectedly, newborns in RACHS category 4 had lower birth weights (3.0 +/- 0.5 kg vs. 3.5 +/- 0.5 kg; P < .05) and a trend toward increased postoperative inotropic score (19 +/- 7 vs. 16 +/- 4), increased postoperative lactic acid (72 +/- 48 vs. 63 +/- 25), increased length of mechanical ventilation (23 +/- 72 days vs. 8 +/- 6 days), increased length of stay (34 +/- 72 days vs. 31 +/- 17 days), and increased mortality (16% vs. 11%) compared with newborns in RACHS category 6. CONCLUSION: Limitations of risk assessment using RACHS in a single-center series of high-risk newborns include the lack of consideration of confounding variables. Further risk adjustments that include such confounding variables are warranted.