Prospective evaluation of acute neurological events after paediatric cardiac surgery.

OBJECTIVES: Children with CHD are at heightened risk of neurodevelopmental problems; however, the contribution of acute neurological events specifically linked to the perioperative period is unclear. AIMS: This secondary analysis aimed to quantify the incidence of acute neurological events in a UK paediatric cardiac surgery population, identify risk factors, and assess how acute neurological events impacted the early post-operative pathway. METHODS: Post-operative data were collected prospectively on 3090 consecutive cardiac surgeries between October 2015 and June 2017 in 5 centres. The primary outcome of analysis was acute neurological event, with secondary outcomes of 6-month survival and post-operative length of stay. Patient and procedure-related variables were described, and risk factors were statistically explored with logistic regression. RESULTS: Incidence of acute neurological events after paediatric cardiac surgery in our population occurred in 66 of 3090 (2.1%) consecutive cardiac operations. 52 events occurred with other morbidities including renal failure (21), re-operation (20), cardiac arrest (20), and extracorporeal life support (18). Independent risk factors for occurrence of acute neurological events were CHD complexity 1.9 (1.1-3.2), p = 0.025, longer operation times 2.7 (1.6-4.8), p < 0.0001, and urgent surgery 3.4 (1.8-6.3), p < 0.0001. Unadjusted comparison found that acute neurological event was linked to prolonged post-operative hospital stay (median 35 versus 9 days) and poorer 6-month survival (OR 13.0, 95% CI 7.2-23.8). CONCLUSION: Ascertainment of acute neurological events relates to local measurement policies and was rare in our population. The occurrence of acute neurological events remains a suitable post-operative metric to follow for quality assurance purposes.

Long-term milrinone therapy in children with dilated cardiomyopathy.

AIM: The aim of this study was to assess the safety and efficacy of long-term milrinone therapy in children with acute decompensated heart failure due to dilated cardiomyopathy (DCM). METHODS: A single-centre retrospective study of all children ≤18 years with acute decompensated heart failure and DCM who received continuous long-term (≥7 consecutive days) intravenous milrinone between January 2008 and January 2022. RESULTS: The 47 patients had a median age of 3.3 months [interquartile range (IQR) 1.0-18.1], weight of 5.7 kg [IQR 4.3-10.1] and fractional shortening of 11.9% [±4.7]. Idiopathic DCM (n = 19) and myocarditis (n = 18) were the most common diagnoses. The median milrinone infusion duration was 27 days [IQR 10-50, range 7-290]. No adverse events necessitated milrinone termination. Nine patients required mechanical circulatory support. Median follow-up was 4.2 years [IQR 2.7-8.6]. On initial admission, four patients died, six were transplanted and 79% [37/47] were discharged home. The 18 readmissions resulted in five more deaths and four transplantations. Cardiac function recovered in 60% [28/47], as measured by normalised fractional shortening. CONCLUSION: Long-term intravenous milrinone is safe and effective in paediatric acute decompensated DCM. Combined with conventional heart failure therapies, it can act as a bridge to recovery and thereby potentially reduce the need for mechanical support or heart transplantation.

Factors associated with unplanned reinterventions and their relation to early mortality after pediatric cardiac surgery.

OBJECTIVE: Unplanned reintervention (uRE) is used as an indicator of patient morbidity and quality of care in pediatric cardiac surgery. We investigated associated factors and early mortality after uREs. METHODS: Morbidity data were prospectively collected in 5 UK centers between 2015 and 2017; uRE included surgical cardiac, interventional transcatheter cardiac, permanent pacemaker, and diaphragm plication procedures. Mortality (30-day and 6-month) in uRE/no-uRE patients was reported before and after matching. Predicted 30-day mortality was calculated using the Partial Risk Adjustment in Surgery score. RESULTS: A total of 3090 procedures (2861 patients) were included (median age, 228 days). There were 146 uREs, resulting in an uRE rate of 4.7%. Partial Risk Adjustment in Surgery score, 30-day mortality and 6-month mortality in uRE and no-uRE groups were 2.4% versus 1.3%, 8.9% versus 1%, and 17.1% versus 2.4%, respectively. After matching, mortality at 6 months remained higher in uRE compared with no-uRE (12.2% vs 1.4%; P = .02; 74 pairs). In the uRE group, 21 out of 25 deaths at 6 months occurred when at least 1 additional postoperative complication was present. In multivariable analysis, neonatal age (P = .002), low weight (P = .009), univentricular heart (P < .001), and arterial shunt (P < .001) were associated with increased risk of uRE, but Partial Risk Adjustment in Surgery score was not (only in univariable analysis). CONCLUSIONS: uREs are a relatively frequent complication after pediatric cardiac surgery and are associated with some patient characteristics, but not the Partial Risk Adjustment in Surgery risk score. Early mortality was higher after uRE, independent of preoperative factors, but linked to other postoperative complications.

What are the important morbidities associated with paediatric cardiac surgery? A mixed methods study.

OBJECTIVES: Given the current excellent early mortality rates for paediatric cardiac surgery, stakeholders believe that this important safety outcome should be supplemented by a wider range of measures. Our objectives were to prospectively measure the incidence of morbidities following paediatric cardiac surgery and to evaluate their clinical and health-economic impact over 6 months. DESIGN: The design was a prospective, multicentre, multidisciplinary mixed methods study. SETTING: The setting was 5 of the 10 paediatric cardiac surgery centres in the UK with 21 months recruitment. PARTICIPANTS: Included were 3090 paediatric cardiac surgeries, of which 666 patients were recruited to an impact substudy. RESULTS: Families and clinicians prioritised:Acute neurological event, unplanned re-intervention, feeding problems, renal replacement therapy, major adverse events, extracorporeal life support, necrotising enterocolitis, postsurgical infection and prolonged pleural effusion or chylothorax.Among 3090 consecutive surgeries, there were 675 (21.8%) with at least one of these morbidities. Independent risk factors for morbidity included neonatal age, complex heart disease and prolonged cardiopulmonary bypass (p<0.001). Among patients with morbidity, 6-month survival was 88.2% (95% CI 85.4 to 90.6) compared with 99.3% (95% CI 98.9 to 99.6) with none of the morbidities (p<0.001). The impact substudy in 340 children with morbidity and 326 control children with no morbidity indicated that morbidity-related impairment in quality of life improved between 6 weeks and 6 months. When compared with children with no morbidities, those with morbidity experienced a median of 13 (95% CI 10.2 to 15.8, p<0.001) fewer days at home by 6 months, and an adjusted incremental cost of £21 292 (95% CI £17 694 to £32 423, p<0.001). CONCLUSIONS: Evaluation of postoperative morbidity is more complicated than measuring early mortality. However, tracking morbidity after paediatric cardiac surgery over 6 months offers stakeholders important data that are of value to parents and will be useful in driving future quality improvement.

Incidence and risk factors for important early morbidities associated with pediatric cardiac surgery in a UK population.

OBJECTIVE: Given excellent 30-day survival for pediatric cardiac surgery, other outcome measures are important. We aimed to study important early postoperative morbidities selected by stakeholders following a rigorous and evidenced-based process, with a view to identifying potential risk factors. METHODS: The incidence of selected morbidities was prospectively measured for 3090 consecutive pediatric cardiac surgical admissions in 5 UK centers between October 2015 and June 2017. The relationship between the candidate risk factors and the incidence of morbidities was explored using multiple regressions. Patient survival, a secondary outcome, was checked at 6 months. RESULTS: A total of 675 (21.8%) procedure episodes led to at least 1 of the following: acute neurologic event, unplanned reoperation, feeding problems, renal replacement therapy, major adverse events, extracorporeal life support, necrotizing enterocolitis, surgical infection, or prolonged pleural effusion. The highest adjusted odds ratio of morbidity was in neonates compared with children, 5.26 (95% confidence interval, 3.90-7.06), and complex heart diseases (eg, hypoplastic left heart), 2.14 (95% confidence interval, 1.41-3.24) compared with low complexity (eg, atrial septal defect, P < .001 for all). Patients with any selected morbidity had a 6-month survival of 88.2% (95% confidence interval, 85.4-90.6) compared with 99.3% (95% confidence interval, 98.9-99.6) with no defined morbidity (P < .001). CONCLUSIONS: Evaluation of postoperative morbidity provides important information over and above 30-day survival and should become a focus for audit and quality improvement. Our results have been used to initiate UK-based audit for 5 of these 9 morbidities, co-develop software for local monitoring of these morbidities, and parent information about these morbidities.

A longer waiting game: bridging children to heart transplant with the Berlin Heart EXCOR device--the United Kingdom experience.

BACKGROUND: Mechanical circulatory support (MCS) is used to support children with end-stage heart failure to heart transplant. METHODS: This was a retrospective cohort study of 7 years' experience with the Berlin Heart (BH) EXCOR (Berlin Heart AG, Berlin Germany) paracorporeal ventricular assist device (VAD) in 2 United Kingdom (UK) pediatric heart transplant centers and the effect of this program on the UK pediatric heart transplant service. RESULTS: Of 102 children who received BH support, 84% survived to transplant or BH explant and 81% survived to discharge. Neither age nor duration of support influenced outcome. Stroke, ongoing requirement for ventilation while on BH, and diagnosis other than dilated cardiomyopathy were the only independent mortality risk factors. Children who weighed < 20 kg had significantly (p = 0.03) longer support times than bigger children. The number of children treated with a BH increased over time (p = 0.01). Currently > 50% of pediatric heart transplants are bridged with a BH; however, pediatric transplants per year have not increased significantly (p = 0.07) CONCLUSIONS: BH use in the UK has allowed significant increases in the number of children with end-stage heart failure who can be successfully bridged to transplant and the length of time they can be supported. The total number of transplants has not increased.

The impact of mechanical circulatory support on outcomes in paediatric heart transplantation.

OBJECTIVES: Internationally, the number of donors for cardiac transplantation has remained static, while the number of patients requiring transplantation for congenital heart disease (CHD) has increased. Although the availability of mechanical circulatory support (MCS) may increase the number of transplants performed by reducing deaths while waiting, it may also lead to increased morbidity post-transplantation. We sought to assess the impact of mechanical support on post-transplant outcomes in a single centre. METHODS: We assessed the outcomes of paediatric (age ≤16 years) heart transplantation in a single unit in the era of mechanical support (1998-2012) by retrospective cohort study. Outcomes before (1998-2005) and after (2005-2012) the routine use of the Berlin Heart EXCOR device were contrasted. RESULTS: A total of 167 patients underwent heart transplantation during this period. The diagnosis was dilated cardiomyopathy in 61.7%, two-ventricle CHD in 11.4%, single ventricle CHD in 16.8% and miscellaneous in 10.1%. Sixty-nine (41%) were bridged to transplant by mechanical support; with extracorporeal membrane oxygenation in 19 (28%), ventricular assist device in 40 (58%) and a combination in 10 (14.0%). Post-transplant mortality at 30 days was significantly greater in those supported by MCS than without (7 vs 1%, P < 0.05), and a greater proportion of patients had neurological (23 vs 8%, P < 0.01) and major respiratory sequelae (20 vs 4%, P < 0.001). There was no significant increase in the need for post-transplant mechanical support (10 vs 6%, P = 0.3) in those supported prior to transplant. The number of transplants performed increased from 67 in 1998-2005 to 100 in the most recent era (2005-2012), and an increased proportion of these patients have been supported mechanically prior to transplantation (51 vs 27%, P < 0.01). CONCLUSION: Along with strategies to increase donor utilization, MCS has allowed an increase in cardiac transplant activity at the expense of a higher early mortality and morbidity.

'Matching Michigan': a 2-year stepped interventional programme to minimise central venous catheter-blood stream infections in intensive care units in England.

BACKGROUND: Bloodstream infections from central venous catheters (CVC-BSIs) increase morbidity and costs in intensive care units (ICUs). Substantial reductions in CVC-BSI rates have been reported using a combination of technical and non-technical interventions. METHODS: We conducted a 2-year, four-cluster, stepped non-randomised study of technical and non-technical (behavioural) interventions to prevent CVC-BSIs in adult and paediatric ICUs in England. Random-effects Poisson regression modelling was used to compare infection rates. A sample of ICUs participated in data verification. RESULTS: Of 223 ICUs in England, 215 (196 adult, 19 paediatric) submitted data on 2479 of 2787 possible months and 147 (66%) provided complete data. The exposure rate was 438 887 (404 252 adult and 34 635 paediatric) CVC-patient days. Over 20 months, 1092 CVC-BSIs were reported. Of these, 884 (81%) were ICU acquired. For adult ICUs, the mean CVC-BSI rate decreased over 20 months from 3.7 in the first cluster to 1.48 CVC-BSIs/1000 CVC-patient days (p<0.0001) for all clusters combined, and for paediatric ICUs from 5.65 to 2.89 (p=0.625). The trend for infection rate reduction did not accelerate following interventions training. CVC utilisation rates remained stable. Pre-ICU infections declined in parallel with ICU-acquired infections. Criterion-referenced case note review showed high agreement between adjudicators (κ 0.706) but wide variation in blood culture sampling rates and CVC utilisation. Generic infection control practices varied widely. CONCLUSIONS: The marked reduction in CVC-BSI rates in English ICUs found in this study is likely part of a wider secular trend for a system-wide improvement in healthcare-associated infections. Opportunities exist for greater harmonisation of infection control practices. Future studies should investigate causal mechanisms and contextual factors influencing the impact of interventions directed at improving patient care.

Mechanical circulatory support after paediatric heart transplantation.

OBJECTIVES: Mechanical circulatory support (MCS) may be required after orthotopic heart transplantation (OHTx) in children for the treatment of failure or rejection. We review the incidence and outcomes of post-transplant MCS in our institution. METHODS: MCS was classified as early (<1 month since transplant) or late (>1 month since transplant) and the support offered was either veno-arterial extra-corporeal membrane oxygenation (VA-ECMO) or a ventricular assist device (VAD). From 2003 to the present, 100 children (<16 years) underwent OHTx. Fifteen (15%) had 17 episodes of MCS. MCS was instituted early in 10 and late in seven episodes. Two children required two episodes of support. VA-ECMO was used in 12 episodes (71%). Two children required VAD support alone (12%). In three (17%) episodes ECMO was subsequently converted from VAD. RESULTS: Among 10 children with early failure, eight were successfully weaned from support with recovery of graft function. In the late failure group, three of six patients died. All but four patients underwent re-transplantation with no perioperative deaths. Overall survival to discharge was 66%. The early failure group shows a better survival rate to hospital discharge compared with the late failure group (78 vs 50%; P < 0.0001). CONCLUSIONS: The incidence of post-transplant MCS for graft failure in our patients was 15%. Early graft failure has a better outcome than late failure. Re-transplantation has good mid-term outcomes in children. A stepwise approach with a multimodality MCS strategy improves survival in this group of patients.