Kate L. Brown

Cardiac ECMO for biventricular hearts after paediatric open heart surgery

Objective: To delineate predictors of hospital survival in a large series of children with biventricular physiology supported with extracorporeal membrane oxygenation (ECMO) after open heart surgery. Results: 81 children were placed on ECMO after open heart surgery. 58% (47 of 81) were transferred directly from cardiopulmonary bypass to ECMO. Hospital survival was 49% (40 of 81) but there were seven late deaths among these survivors (18%). Factors that improved the odds of survival were initiation of ECMO in theatre (64% survival (30 of 47)) rather than the cardiac intensive care unit (29% survival (10 of 34)) and initiation of ECMO for reactive pulmonary hypertension. Important adverse factors for hospital survival were serious mechanical ECMO circuit problems, renal support, residual lesions, and duration of ECMO. Conclusions: Hospital survival of children with biventricular physiology who require cardiac ECMO is similar to that found in series that include univentricular hearts, suggesting that successful cardiac ECMO is critically dependent on the identification of hearts with reversible ventricular dysfunction. In our experience of postoperative cardiac ECMO, the higher survival of patients cannulated in the operating room than in the cardiac intensive care unit is due to early effective support preventing prolonged hypoperfusion and the avoidance of a catastrophic cardiac arrest.

Healthcare-associated infection in pediatric patients on extracorporeal life support: The role of multidisciplinary surveillance.

Objective: To describe the use of a multidisciplinary approach to sepsis surveillance and evaluate impact on outcome. Design: Prospective clinical study or clinical audit cycle. Setting: Tertiary pediatric extracorporeal membrane oxygenation (ECMO) center. Patients: Patients were 215 children supported with ECMO January 1999 to December 2004. Interventions: A multidisciplinary team met monthly to evaluate cases of bloodstream infection and mediastinitis, review trends, and update unit policies. Changes in practice were made at the end of 2001 in order to address a perceived high rate of sepsis: a) reeducation; b) introduction of electively preprimed ECMO circuits; and c) preference for neck rather than chest cannulation in cardiac patients. Prophylactic antibiotics were used from preprocedure for 24 hrs only throughout the study. Measurements and Main Results: Over the entire study period, 39 children had 47 septic episodes, with a rate of 24.9 per 1000 ECMO days. Multiple logistic regression analyses indicated that infection was associated with duration of ECMO support (odds ratio 1.24; 95% confidence interval 1.15, 1.35 per day) and case type: Closed vs. open chest was protective in cardiac patients (odds ratio 0.08; 95% confidence interval 0.01, 0.50). Infection increased the odds of death by 2.01 (95% confidence interval 1.00, 4.05), but this effect was less important than case type and ECMO days. After policy changes were implemented, there was a reduction in sepsis from 29.3 to 20.1 episodes per 1000 ECMO days. There was reduced sepsis in respiratory patients: neonates from 28.0 to 6.6 and pediatric patients from 42.4 to 16.9 episodes per 1000 ECMO days. Despite policy changes, sepsis remained a problem in cardiac patients with open sternum: 65.1 per 1000 ECMO days. Conclusions: ECMO support is a high-risk setup for nosocomial infection, in particular for cardiac patients with open sternum for whom antibiotic prophylaxis is justified. Multidisciplinary surveillance offers an excellent approach for quality improvement in this challenging field.

Trends in 30-day mortality rate and case mix for paediatric cardiac surgery in the UK between 2000 and 2010.

Objectives To explore changes over time in the 30-day mortality rate for paediatric cardiac surgery and to understand the role of attendant changes in the case mix. Methods, setting and participants Included were: all mandatory submissions to the National Institute of Cardiovascular Outcomes Research (NICOR) relating to UK cardiac surgery in patients aged <16u2005years. The χ2 test for trend was used to retrospectively analyse the proportion of surgical episodes ending in 30-day mortality and with various case mix indicators, in 10 consecutive time periods, from 2000 to 2010. Comparisons were made between two 5-year eras of: 30-day mortality, period prevalence and mean age for 30 groups of specific operations. Main outcome measure 30-day mortality for an episode of surgical management. Results Our analysis includes 36u2005641 surgical episodes with an increase from 2283 episodes in 2000 to 3939 in 2009 (p<0.01). The raw national 30-day mortality rate fell over the period of review from 4.3% (95% CI 3.5% to 5.1%) in 2000 to 2.6% (95% CI 2.2% to 3.0%) in 2009/2010 (p<0.01). The case mix became more complex in terms of the percentage of patients <2.5u2005kg (p=0.05), with functionally univentricular hearts (p<0.01) and higher risk diagnoses (p<0.01). In the later time era, there was significant improvement in 30-day mortality for arterial switch with ventricular septal defect (VSD) repair, patent ductus arteriosus ligation, Fontan-type operation, tetralogy of Fallot and VSD repair, and the mean age of patients fell for a range of operations performed in infancy. Conclusions The raw 30-day mortality rate for paediatric cardiac surgery fell over a decade despite a rise in the national case mix complexity, and compares well with international benchmarks. Definitive repair is now more likely at a younger age for selected infants with congenital heart defects.

Outcomes following extracorporeal membrane oxygenation in children with cardiac disease.

Extracorporeal membrane oxygenation is a commonly used form of mechanical circulatory support in children with congenital or acquired heart disease and cardiac failure refractory to conventional medical therapies. In children with heart disease who suffer cardiac arrest, extracorporeal membrane oxygenation has been successfully used to provide cardiopulmonary support when conventional resuscitation has failed to establish return of spontaneous circulation. Survival to hospital discharge for children with heart disease support is approximately 40% but varies widely based on age, indication for support, and underlying cardiac disease. Although extracorporeal membrane oxygenation is lifesaving in many instances, it is associated with many complications and is expensive. Thus, a clear understanding of survival to discharge and long-term functional and neurologic outcomes are essential to guide the use of extracorporeal membrane oxygenation now and in the future. This review, part of the Pediatric Cardiac Intensive Care Society/Extracorporeal Life Support Organization Joint Statement on Mechanical Circulatory Support, summarizes current knowledge on short- and long-term outcomes for extracorporeal membrane oxygenation used to support children with cardiac disease.

Long-Term Survival Outcomes and Causes of Late Death in Neonates, Infants, and Children Treated With Extracorporeal Life Support

Objectives: Extracorporeal life support is a resource-intense treatment offered to the sickest patients. We aimed to investigate long-term survival rates and late deaths. Design: Retrospective cohort study. Setting: Tertiary referral center for extracorporeal life support. Patients: All patients who required extracorporeal life support from 1992 to 2010 at our center. The U.K. National Health Service number was used to trace survival status of all patients who received extracorporeal life support at our center, grouped by diagnosis. Death more than 90 days after extracorporeal life support was defined as late, and these medical records were reviewed. Interventions: None. Measurements and Main Results: A total of 741 children with 272 early deaths (36.7%) and 46 late deaths (6.2%) were included. Median follow-up time in survivors was 7.1 (interquartile range, 3.0–11.9) years. Five-year survival estimates were highest for meconium aspiration syndrome 88.0% (95% CI, 80.6–92.7%) and lowest for congenital heart disease 32.3% (95% CI, 25.1–39.8%). Five-year survival estimates conditional on being alive at 90 days were highest for meconium aspiration syndrome 97.9% (95% CI, 92.0–99.5%) and lowest for congenital diaphragmatic hernia 73.6% (52.3–86.5%). There was increased risk of late death in congenital diaphragmatic hernia, congenital heart disease, and acquired heart disease (p < 0.001, p < 0.01, p = 0.01) in comparison with the risk in meconium aspiration syndrome. For 46 late deaths, 17 had a cardiac cause, 16 had a respiratory cause, 10 had a comorbid cause, one died of sepsis, and in two, causation was unknown. Conclusions: Although the majority of deaths were early, late mortality was observed following extracorporeal life support. Late deaths were more prevalent in children with underlying complex long-term conditions, particularly heart disease and congenital diaphragmatic hernia. Evaluation of longer term survival is an important component of audit for extracorporeal life support outcomes.

Development of a diagnosis- and procedure-based risk model for 30-day outcome after pediatric cardiac surgery

OBJECTIVEnThe study objective was to develop a risk model incorporating diagnostic information to adjust for case-mix severity during routine monitoring of outcomes for pediatric cardiac surgery.nnnMETHODSnData from the Central Cardiac Audit Database for all pediatric cardiac surgery procedures performed in the United Kingdom between 2000 and 2010 were included: 70% for model development and 30% for validation. Units of analysis were 30-day episodes after the first surgical procedure. We used logistic regression for 30-day mortality. Risk factors considered included procedural information based on Central Cardiac Audit Database specific procedures, diagnostic information defined by 24 primary cardiac diagnoses and univentricular status, and other patient characteristics.nnnRESULTSnOf the 27,140 30-day episodes in the development set, 25,613 were survivals, 834 were deaths, and 693 were of unknown status (mortality, 3.2%). The risk model includes procedure, cardiac diagnosis, univentricular status, age band (neonate, infant, child), continuous age, continuous weight, presence of non-Down syndrome comorbidity, bypass, and year of operation 2007 or later (because of decreasing mortality). A risk score was calculated for 95% of cases in the validation set (weight missing in 5%). The model discriminated well; the C-index for validation set was 0.77 (0.81 for post-2007 data). Removal of all but procedural information gave a reduced C-index of 0.72. The model performed well across the spectrum of predicted risk, but there was evidence of underestimation of mortality risk in neonates undergoing operation from 2007.nnnCONCLUSIONSnThe risk model performs well. Diagnostic information added useful discriminatory power. A future application is risk adjustment during routine monitoring of outcomes in the United Kingdom to assist quality assurance.

Cost Utility Evaluation of Extracorporeal Membrane Oxygenation as a Bridge to Transplant for Children With End-Stage Heart Failure due to Dilated Cardiomyopathy

BACKGROUNDnExtracorporeal membrane oxygenation (ECMO) and cardiac transplantation are recognized to be expensive.nnnMETHODSnWe performed a cost utility evaluation with a decision model approach, including 75 children with dilated cardiomyopathy. A cohort of patients with end stage heart failure who were offered ECMO bridging was compared with a similar cohort offered only conventional intensive care. Outcome was measured in cost per quality adjusted life year (QALY).nnnRESULTSnMedian follow-up was 4.39 years (interquartile range, 1.83-5.74 years), during which 50 children underwent transplantation, 16 had a period of recovery, and 25 died. ECMO bridging was highly effective (hazard ratio, 0.181; 95% confidence interval, 0.067-0.489; p = 0.001) but exceeded conventional criteria for cost-effectiveness. The reference incremental cost-effectiveness ratio (ICER) was pound65,645 per QALY and pound54,284 per life-year gained. Average life expectancy rose from 6.78 to 9.79 years and costs from pound146,398 to pound309,599 per patient with ECMO bridging. The ICER was sensitive to ECMO cost, the long-term transplant survival rate, and quality of life in transplant recipients.nnnCONCLUSIONSnECMO bridging is effective but expensive. The eligible target population is small, nationally, positively influencing affordability. We strongly support our national policy of mechanical bridge to transplant for suitable children in end stage heart failure. Cost effectiveness could be optimized by: 1) increased availability of organ donors, 2) reduction in mechanical support costs possibly by alternate devices and 3) inclusion of patients most likely to benefit.

Percutaneous left ventricular "vent" insertion for left heart decompression during extracorporeal membrane oxygenation

Objective Description of a novel method of left ventricular decompression by a percutaneous technique under transthoracic echocardiographic guidance. Design Case report. Setting Supraregional cardiac referral center. Patient Patient with end-stage cardiomyopathy. Interventions Percutaneous insertion of a modified Mullins transseptal sheath under transthoracic echocardiographic guidance. Measurements and Main Results Successful decompression of the left ventricle and subsequent orthotopic heart transplantation. Conclusions In patients at high risk of bleeding, a percutaneous technique may be useful for left ventricular decompression.

Near-fatal grape aspiration with complicating acute lung injury successfully treated with extracorporeal membrane oxygenation

Objective In this report of a near-fatal case of grape aspiration successfully treated with extracorporeal membrane oxygenation (ECMO), we highlight the danger of feeding seedless grapes to young children and demonstrate that ECMO can provide cardiopulmonary support for cases of acquired large-airway disruption and can facilitate therapeutic intervention. Design Case report. Setting A tertiary pediatric intensive care unit and ECMO center. Patient A healthy 14-month-old boy aspirated a seedless grape while playing at home and suffered a cardiopulmonary arrest of 15 mins in duration. He responded to advanced life support with return of cardiac output but developed intractable cardiopulmonary failure secondary to aspirated grape particles and postobstructive pulmonary edema. Interventions The patient was emergently transferred to the regional ECMO center and placed on venoarterial ECMO. Bronchoscopies were performed in the stable environment provided by ECMO, aspirated particles were removed from the large airways, and lung recovery was facilitated. Measurements and Main Results End-organ perfusion was restored via ECMO during a period of severe intractable cardiopulmonary failure. Pulmonary recovery occurred during a 6-day ECMO run and was facilitated by therapeutic bronchoscopy. The patient was reviewed 1 yr later and has made a full neurodevelopmental recovery, despite a 15-min out-of-hospital cardiac arrest. Conclusions Aspiration of a seedless grape is a life-threatening event in a small child. This danger is not fully appreciated by parents in the UK. ECMO may be life saving in cases of acquired large-airway disruption resulting in severe cardiopulmonary failure, including foreign body aspiration, as long as end-organ perfusion is maintained.

Fast-track paediatric cardiac surgery: the feasibility and benefits of a protocol for uncomplicated cases

OBJECTIVEnFast-track patient pathways for cardiac surgery are used in adult practice and by necessity is a mainstay in the developing world. We aimed to introduce a fast-track protocol for uncomplicated paediatric open-heart surgery cases and to subsequently review the results of this change in practice.nnnMETHODSnA fast-track protocol co-ordinated by the Advanced Nurse Practitioners was introduced in January 2006 for children aged over 6 months undergoing uncomplicated open-heart procedures. We conducted a review of prospectively collected data on all included patients. The setting was a tertiary paediatric cardiac surgical centre in the UK. The outcome measures for audit were: patient fitness to leave the intensive care unit (ICU) on the day of surgery and hospital length of stay.nnnRESULTSnIncluded children had a mean age 6 (standard deviation (SD) 4.9) years and mean weight 22.7 (SD 17.6) kg. Of the 194 patients included, 153 (79%) were fit to leave the ICU on the day of surgery. Patients undergoing surgery for ventricular septal defect: odds ratio (OR) 2.8 (95% CI: 1.2-5.6) P=0.01 and left ventricular outflow tract obstruction: OR 5.5 (95% CI: 1.4-21.2) P=0.01, were more likely to be unfit than atrial septal defect and right ventricular outflow tract obstruction. Patients undergoing surgery in the afternoon were more likely to be unfit than those undergoing surgery in the morning: OR 2.3 (95% CI: 1.2-4.8) P=0.03. No relationship was found between age or weight and fitness to fast track. Median length of hospital stay for the whole cohort was 3 (range: 2-11) days. After adjustment for case mix, there was significant evidence that length of hospital stay reduced as experience with the protocol increased over the series of patients RC -0.02 (95% CI: -0.01 to -0.03) P<0.01.nnnCONCLUSIONnA fast-track programme can be implemented safely and effectively if the appropriate support including a step-down ward area is put in place. Greater experience with this type of protocol leads to reductions in the length of hospital stay for children aged over 6 months undergoing uncomplicated open-heart surgery. Fast-track cases should be performed in the morning.