Padmanabhan Ramnarayan

Effect of specialist retrieval teams on outcomes in children admitted to paediatric intensive care units in England and Wales: a retrospective cohort study

BACKGROUND Intensive care services for children have undergone substantial centralisation in the UK. Along with the establishment of regional paediatric intensive care units (PICUs), specialist retrieval teams were set up to transport critically ill children from other hospitals. We studied the outcome of children transferred from local hospitals to PICUs. METHODS We analysed data that were gathered for a cohort of children (<or=16 years) admitted consecutively to 29 PICUs in England and Wales during 4 years (Jan 1, 2005, to Dec 31, 2008). We compared unplanned admissions from wards within the same hospital as the PICU and from other hospitals; interhospital transfers by non-specialist and specialist retrieval teams; and patients transferred to their nearest PICU and those who were not. Primary outcome measures were mortality rate in PICU and length of stay in PICU. We analysed data by use of logistic regression analysis. FINDINGS There were 57 997 admissions to PICUs during the study. Nearly half of unplanned admissions (17 649 [53%] of 33 492) were from other hospitals. Although children admitted from other hospitals were younger (median 10 months [IQR 1-55] vs 18 months [3-85]), sicker at admission (median predicted risk of mortality 6% [4-10] vs 4% [2-7]), stayed longer in PICUs (75 h [33-153] vs 43 h [18-116]), and had higher crude mortality rates (1384 [8%] of 17 649 vs 996 [6%] of 15 843; odds ratio 1.27, 95% CI 1.16-1.38), the risk-adjusted mortality rate in PICUs was lower than among children admitted from within the same hospital (0.65, 0.53-0.80). In a multivariable analysis, use of a specialist retrieval team for transfer was associated with improved survival (0.58, 0.39-0.87). INTERPRETATION These findings support the policy of combining centralisation of intensive care services for children with transfer by specialist retrieval teams. FUNDING National Clinical Audit and Patient Outcomes Programme through Healthcare Quality Improvement Partnership, Health Commission Wales Specialised Services, National Health Service (NHS) Lothian and National Service Division NHS Scotland, the Royal Belfast Hospital for Sick Children, and the Pan Thames PICU Commissioning Consortium.

Characteristics of deaths occurring in hospitalised children: changing trends

Background: Despite a gradual shift in the focus of medical care among terminally ill patients to a palliative model, studies suggest that many children with life-limiting chronic illnesses continue to die in hospital after prolonged periods of inpatient admission and mechanical ventilation. Objectives: To (1) examine the characteristics and location of death among hospitalised children, (2) investigate yearwise trends in these characteristics and (3) test the hypothesis that professional ethical guidance from the UK Royal College of Paediatrics and Child Health (1997) would lead to significant changes in the characteristics of death among hospitalised children. Methods: Routine administrative data from one large tertiary-level UK children’s hospital was examined over a 7-year period (1997–2004) for children aged 0–18 years. Demographic details, location of deaths, source of admission (within hospital vs external), length of stay and final diagnoses (International Classification of Diseases-10 codes) were studied. Statistical significance was tested by the Kruskal–Wallis analysis of ranks and median test (non-parametric variables), χ2 test (proportions) and Cochran–Armitage test (linear trends). Results: Of the 1127 deaths occurring in hospital over the 7-year period, the majority (57.7%) were among infants. The main diagnoses at death included congenital malformations (22.2%), perinatal diseases (18.1%), cardiovascular disorders (14.9%) and neoplasms (12.4%). Most deaths occurred in an intensive care unit (ICU) environment (85.7%), with a significant increase over the years (80.1% in 1997 to 90.6% in 2004). There was a clear increase in the proportion of admissions from in-hospital among the ICU cohort (14.8% in 1998 to 24.8% in 2004). Infants with congenital malformations and perinatal conditions were more likely to die in an ICU (OR 2.42, 95% CI 1.65 to 3.55), and older children with malignancy outside the ICU (OR 6.5, 95% CI 4.4 to 9.6). Children stayed for a median of 13 days (interquartile range 4.0–23.25 days) on a hospital ward before being admitted to an ICU where they died. Conclusions: A greater proportion of hospitalised children are dying in an ICU environment. Our experience indicates that professional ethical guidance by itself may be inadequate in reversing the trends observed in this study.

ISABEL: a web-based differential diagnostic aid for paediatrics: results from an initial performance evaluation

Aims: To test the clinical accuracy of a web based differential diagnostic tool (ISABEL) for a set of case histories collected during a two stage evaluation. Methods: Setting: acute paediatric units in two teaching and two district general hospitals in the southeast of England. Materials: sets of summary clinical features from both stages, and the diagnoses expected for these features from stage I (hypothetical cases provided by participating clinicians in August 2000) and final diagnoses for cases in stage II (children presenting to participating acute paediatric units between October and December 2000). Main outcome measure: presence of the expected or final diagnosis in the ISABEL output list. Results: A total of 99 hypothetical cases from stage I and 100 real life cases from stage II were included in the study. Cases from stage II covered a range of paediatric specialties (n = 14) and final diagnoses (n = 55). ISABEL displayed the diagnosis expected by the clinician in 90/99 hypothetical cases (91%). In stage II evaluation, ISABEL displayed the final diagnosis in 83/87 real cases (95%). Conclusion: ISABEL showed acceptable clinical accuracy in producing the final diagnosis for a variety of real as well as hypothetical case scenarios.

Impregnated central venous catheters for prevention of bloodstream infection in children (the CATCH trial): a randomised controlled trial

BACKGROUND Impregnated central venous catheters are recommended for adults to reduce bloodstream infections but not for children because there is not enough evidence to prove they are effective. We aimed to assess the effectiveness of any type of impregnation (antibiotic or heparin) compared with standard central venous catheters to prevent bloodstream infections in children needing intensive care. METHODS We did a randomised controlled trial of children admitted to 14 English paediatric intensive care units. Children younger than 16 years were eligible if they were admitted or being prepared for admission to a participating paediatric intensive care unit and were expected to need a central venous catheter for 3 or more days. Children were randomly assigned (1:1:1) to receive a central venous catheter impregnated with antibiotics, a central venous catheter impregnated with heparin, or a standard central venous catheter with computer generated randomisation in blocks of three and six, stratified by method of consent, site, and envelope storage location within the site. The clinician responsible for inserting the central venous catheter was not masked to allocation, but allocation was concealed from patients, their parents, and the paediatric intensive care unit personnel responsible for their care. The primary outcome was time to first bloodstream infection between 48 h after randomisation and 48 h after central venous catheter removal with impregnated (antibiotic or heparin) versus standard central venous catheters, assessed in the intention-to-treat population. Safety analyses compared central venous catheter-related adverse events in the subset of children for whom central venous catheter insertion was attempted (per-protocol population). This trial is registered with ISRCTN number, ISRCTN34884569. FINDINGS Between Nov 25, 2010, and Nov 30, 2012, 1485 children were recruited to this study. We randomly assigned 502 children to receive standard central venous catheters, 486 to receive antibiotic-impregnated catheters, and 497 to receive heparin-impregnated catheters. Bloodstream infection occurred in 18 (4%) of those in the standard catheters group, 7 (1%) in the antibiotic-impregnated group, and 17 (3%) assigned to heparin-impregnated catheters. Primary analyses showed no effect of impregnated (antibiotic or heparin) catheters compared with standard central venous catheters (hazard ratio [HR] for time to first bloodstream infection 0.71, 95% CI 0.37-1.34). Secondary analyses showed that antibiotic central venous catheters were better than standard central venous catheters (HR 0.43, 0.20-0.96) and heparin central venous catheters (HR 0.42, 0.19-0.93), but heparin did not differ from standard central venous catheters (HR 1.04, 0.53-2.03). Clinically important and statistically significant absolute risk differences were identified only for antibiotic-impregnated catheters versus standard catheters (-2.15%, 95% CI -4.09 to -0.20; number needed to treat [NNT] 47, 95% CI 25-500) and antibiotic-impregnated catheters versus heparin-impregnated catheters (-1.98%, -3.90 to -0.06, NNT 51, 26-1667). Nine children (2%) in the standard central venous catheter group, 14 (3%) in the antibiotic-impregnated group, and 8 (2%) in the heparin-impregnated group had catheter-related adverse events. 45 (8%) in the standard group, 35 (8%) antibiotic-impregnated group, and 29 (6%) in the heparin-impregnated group died during the study. INTERPRETATION Antibiotic-impregnated central venous catheters significantly reduced the risk of bloodstream infections compared with standard and heparin central venous catheters. Widespread use of antibiotic-impregnated central venous catheters could help prevent bloodstream infections in paediatric intensive care units. FUNDING National Institute for Health Research, UK.

Validation of a diagnostic reminder system in emergency medicine: a multi‐centre study

Background: Diagnostic error is a significant problem in emergency medicine, where initial clinical assessment and decision making is often based on incomplete clinical information. Traditional computerised diagnostic systems have been of limited use in the acute setting, mainly due to the need for lengthy system consultation. We evaluated a novel web-based reminder system, which provides rapid diagnostic advice to users based on free text search terms. Methods: Clinical data collected from patients presenting to three emergency departments with acute medical problems were entered into the diagnostic system. The displayed results were assessed against the final discharge diagnoses for patients who were admitted to hospital (diagnostic accuracy) and against a set of “appropriate” diagnoses for each case provided by an expert panel (potential utility). Results: Data were collected from 594 patients (53.4% of screened attendances). Mean age was 49.4 years (95% CI 47.7 to 51.1) and the majority had significant past illnesses. Most were assessed first by junior doctors (70%) and 266/594 (44.6%) were admitted to hospital. Overall, the diagnostic system displayed the final discharge diagnosis in 95% of inpatients and 90% of “must-not-miss” diagnoses suggested by the expert panel. The discharge diagnosis appeared within the first 10 suggestions in 78% of cases. Conclusions: The Isabel diagnostic aid has been shown to be of potential use in reminding junior doctors of key diagnoses in the emergency department. The effects of its widespread use on decision making and diagnostic error can be clarified by evaluating its impact on routine clinical decision making.

Timing of Death In Children Referred For Intensive Care With Severe Sepsis: Implications For Interventional Studies

Objective: Early deaths in pediatric sepsis may limit the impact of therapies that can only be provided on PICUs. By introducing selection and survivorship biases, these very early deaths may also undermine the results of trials that employ standard consent procedures. We hypothesized that: 1) the majority of deaths in children with severe sepsis occur very early, within 24 hours of referral to PICU; and 2) a significant proportion of deaths occur before PICU admission. Design, Setting, and Patients: We studied consecutive referrals of newborns through to 16 years of age, between 2005 and 2011 to the Children’s Acute Transport Service, the North Thames regional pediatric intensive care transport service, with a working diagnosis of “sepsis,” “severe sepsis,” “meningococcal sepsis,” or “septic shock.” Interventions: The primary outcome measure was the proportion of deaths within 24 hours of referral. Survival distributions of previously healthy children were compared with those with significant comorbidities. Measurements and Main Results: Thirteen thousand four hundred and nine referrals were made to Children’s Acute Transport Service, of whom 703 (5%) met inclusion criteria. Data on survival to 1 year were available in 627 of 703 patients (89%). One hundred thirty children (130/627; 21%; 95% CI, 18–24%) died in the first year. A higher proportion of children with comorbidity cases (46/85, 54%, 44–64) died compared with previously healthy cases (84/542; 16%; 13–19; p < 0.0005, Fisher exact test). Seventy-one deaths occurred within 24 hours of PICU referral (71/130, 55%, 46–63). The timing of death differed with comorbidity. Similar proportions of children survived to 24 hours (previously healthy children 90% vs children with comorbidity 83%, p = 0.06). However, deaths after 24 hours were infrequent among previously healthy cases (28/84 deaths, 33%, 24–44%) compared with children with comorbidity cases (31/46 deaths, 66%, 53–79%) (p < 0.001, Fisher exact test). Conclusions: This majority of deaths among children referred for pediatric intensive care with for severe sepsis occur within 24 hours. This has important implications for future clinical trials and quality improvement initiatives aimed at improving sepsis outcomes.

Stabilisation of critically ill children at the district general hospital prior to intensive care retrieval: a snapshot of current practice

Objective To describe current practice during stabilisation of children presenting with critical illness to the district general hospital (DGH), preceding retrieval to intensive care. Design Observational study using prospectively collected transport data. Setting A centralised intensive care retrieval service in England and referring DGHs. Patients Emergency transports to intensive care during 2-month epochs from 4 consecutive years (2005–2008). Interventions None. Main outcome measures Proportion of key airway, breathing, and circulatory and neurological stabilisation procedures, such as endotracheal intubation, mechanical ventilation, vascular access, and initiation of inotropic agents, performed by referring hospital staff prior to the arrival of the retrieval team. Results 706 emergency retrievals were examined over a 4-year period. The median age of transported children was 10 months (IQR, 18 days to 43 months). DGH staff performed the majority of endotracheal intubations (93.7%, CI 91.3% to 95.5%), initiated mechanical ventilation in 76.9% of cases (CI 73.0% to 80.4%), inserted central venous catheters frequently (67.4%, CI 61.7% to 72.6%), and initiated inotropic agents in 43.7% (CI 36.6% to 51.1%). The retrieval team was more likely to perform interventions such as reintubation for air leak, repositioning of misplaced tracheal tubes, and administration of osmotic agents for raised intracranial pressure. The performance of one or more interventions by the retrieval team was associated with severity of illness, rather than patient age, diagnostic group, or team response time (OR 3.62, 95% CI 1.47 to 8.92). Conclusions DGH staff appropriately performs the majority of initial stabilisation procedures in critically ill children prior to retrieval. This practice has not changed significantly for the past 4 years, attesting to the crucial role played by district hospital staff in a centralised model of paediatric intensive care.

Measuring the performance of an inter-hospital transport service

Most district general hospital (DGH) paediatricians will have referred critically ill children to a retrieval team at some point in their career. Inter-hospital transport services have developed in response to the centralisation of specialist services such as intensive care, with the aim of ensuring safe and rapid transport of sick children to tertiary centres.1–3 In many parts of the UK, retrievals are undertaken by staff despatched from the receiving intensive care unit (ICU), although dedicated regional transport teams, similar to those in North America and Australia, have also evolved recently for neonatal and paediatric transfers.4–6 Regional transport teams allow concentration of expertise and often serve as a single point of contact for immediate advice, information on an appropriate ICU bed and access to a specialist team. Clinicians, commissioners and patients justifiably expect specialist services to deliver high quality, cost-effective care. While a number of quality indicators have been proposed for intensive care,7 there is currently no consensus on how the performance of an inter-hospital transport service can be measured. This is likely to be a significant drawback in the future. Ongoing changes in the NHS such as re-organisation of children’s emergency services, implementation of the recommendations of the Darzi Next Steps Review, and proliferation of managed clinical networks are all likely to greatly increase the need for safe and efficient patient transfer between ambulatory, secondary and tertiary care settings.8–11 Payment-by-results is also likely to generate greater competition between existing NHS providers and encourage the involvement of independent sector providers in patient transport.12 The absence of agreed key performance indicators or reference values means that transport teams will be unable to measure their own performance over time and commissioners will not be able to compare services or benchmark performance, raising …

Ambulance and aeromedical accident rates during emergency retrieval in Great Britain

The retrieval of critically ill patients is frequently done in difficult circumstances and often under considerable time pressures. These adverse conditions have a finite risk of serious injury or death. The level of risk is poorly described in the literature and reliable data on accident rates are hard to find. Most of the information comes from North America. There are no clear published statistics for the UK. We report for the first time data on accidents and casualties involving vehicles classified as having an ambulance body type and air ambulances within Great Britain between 1999 and 2004.

A new scoring system derived from base excess and platelet count at presentation predicts mortality in paediatric meningococcal sepsis

IntroductionThe aim of this study was to derive a novel prognostic score for mortality in paediatric meningococcal sepsis (MS) based on readily available laboratory markers.MethodsA multicentre retrospective cohort study for the consortium set and a single centre retrospective study for replication set. The consortium set were 1,073 children (age 1 week to 17.9 years) referred over a 15-year period (1996 to 2011), who had an admission diagnosis of MS, referred to paediatric intensive care units (PICUs) in six different European centres. The consortium set was split into a development set and validation set to derive the score. The replication set were 134 children with MS (age 2 weeks to 16 years) referred over a 4-year period (2007 to 2011) to PICUs via the Childrens Acute Transport Service (CATS), London.ResultsA total of 85/1,073 (7.9%) children in the consortium set died. A total of 16/134 (11.9%) children in the replication set died. Children dying in the consortium set had significantly lower base excess, C-reactive protein (CRP), platelet and white cell count, more deranged coagulation and higher lactate than survivors. Paediatric risk of mortality (PRISM) score, Glasgow meningococcal septicaemia prognosis score (GMSPS) and Rotterdam score were also higher. Using the consortium set, a new scoring system using base excess and platelet count at presentation, termed the BEP score, was mathematically developed and validated. BEP predicted mortality with high sensitivity and specificity scores (area under the curve (AUC) in the validation set = 0.86 and in the replication set = 0.96). In the validation set, BEP score performance (AUC = 0.86, confidence interval (CI): 0.80 to 0.91) was better than GMSPS (AUC = 0.77, CI: 0.68, 0.85), similar to Rotterdam (AUC = 0.87, CI: 0.81 to 0.93) and not as good as PRISM (AUC = 0.93, CI: 0.85 to 0.97).ConclusionsThe BEP score, relying on only two variables that are quickly and objectively measurable and readily available at presentation, is highly sensitive and specific in predicting death from MS in childhood.