Interventions to reduce central venous catheter-associated infections in children: which ones are beneficial?

CATheter Infections in CHildren (CATCH): a randomised controlled trial and economic evaluation comparing impregnated and standard central venous catheters in children

BACKGROUND

Impregnated central venous catheters (CVCs) are recommended for adults to reduce bloodstream infection (BSI) but not for children.

OBJECTIVE

To determine the effectiveness of impregnated compared with standard CVCs for reducing BSI in children admitted for intensive care.

DESIGN

Multicentre randomised controlled trial, cost-effectiveness analysis from a NHS perspective and a generalisability analysis and cost impact analysis.

SETTING

14 English paediatric intensive care units (PICUs) in England.

PARTICIPANTS

Children aged < 16 years admitted to a PICU and expected to require a CVC for ≥ 3 days.

INTERVENTIONS

Heparin-bonded, antibiotic-impregnated (rifampicin and minocycline) or standard polyurethane CVCs, allocated randomly (1 : 1 : 1). The intervention was blinded to all but inserting clinicians.

MAIN OUTCOME MEASURE

Time to first BSI sampled between 48 hours after randomisation and 48 hours after CVC removal. The following data were used in the trial: trial case report forms; hospital administrative data for 6 months pre and post randomisation; and national-linked PICU audit and laboratory data.

RESULTS

In total, 1859 children were randomised, of whom 501 were randomised prospectively and 1358 were randomised as an emergency; of these, 984 subsequently provided deferred consent for follow-up. Clinical effectiveness - BSIs occurred in 3.59% (18/502) of children randomised to standard CVCs, 1.44% (7/486) of children randomised to antibiotic CVCs and 3.42% (17/497) of children randomised to heparin CVCs. Primary analyses comparing impregnated (antibiotic and heparin CVCs) with standard CVCs showed no effect of impregnated CVCs [hazard ratio (HR) 0.71, 95% confidence interval (CI) 0.37 to 1.34]. Secondary analyses showed that antibiotic CVCs were superior to standard CVCs (HR 0.43, 95% CI 0.20 to 0.96) but heparin CVCs were not (HR 1.04, 95% CI 0.53 to 2.03). Time to thrombosis, mortality by 30 days and minocycline/rifampicin resistance did not differ by CVC. Cost-effectiveness - heparin CVCs were not clinically effective and therefore were not cost-effective. The incremental cost of antibiotic CVCs compared with standard CVCs over a 6-month time horizon was £1160 (95% CI -£4743 to £6962), with an incremental cost-effectiveness ratio of £54,057 per BSI avoided. There was considerable uncertainty in costs: antibiotic CVCs had a probability of 0.35 of being dominant. Based on index hospital stay costs only, antibiotic CVCs were associated with a saving of £97,543 per BSI averted. The estimated value of health-care resources associated with each BSI was £10,975 (95% CI -£2801 to £24,751). Generalisability and cost-impact - the baseline risk of BSI in 2012 for PICUs in England was 4.58 (95% CI 4.42 to 4.74) per 1000 bed-days. An estimated 232 BSIs could have been averted in 2012 using antibiotic CVCs. The additional cost of purchasing antibiotic CVCs for all children who require them (£36 per CVC) would be less than the value of resources associated with managing BSIs in PICUs with standard BSI rates of > 1.2 per 1000 CVC-days.

CONCLUSIONS

The primary outcome did not differ between impregnated and standard CVCs. However, antibiotic-impregnated CVCs significantly reduced the risk of BSI compared with standard and heparin CVCs. Adoption of antibiotic-impregnated CVCs could be beneficial even for PICUs with low BSI rates, although uncertainty remains whether or not they represent value for money to the NHS. Limitations - inserting clinicians were not blinded to allocation and a lower than expected event rate meant that there was limited power for head-to-head comparisons of each type of impregnation. Future work - adoption of impregnated CVCs in PICUs should be considered and could be monitored through linkage of electronic health-care data and clinical data on CVC use with laboratory surveillance data on BSI.

TRIAL REGISTRATION

ClinicalTrials.gov NCT01029717.

FUNDING

This project was funded by the NIHR Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 20, No. 18. See the NIHR Journals Library website for further project information.

Clinical Trial Decisions in Difficult Circumstances: Parental Consent Under Time Pressure

Treatments and interventions used to care for children in emergencies should be based on strong evidence. Well-designed clinical trials investigating these interventions for children are therefore indispensable. Parental informed consent is a key ethical requirement for the enrollment of children in such studies. However, if time is limited because of an urgent need for intervention, there are additional ethical challenges to adequately support the informed consent process. The acute situation and associated psychological impact may compromise the ability of parents to give informed consent. Little evidence exists to guide the process of consent seeking for a child's research participation when time is limited. It is also unclear in what circumstances alternatives to prospective informed consent could be applied. This article describes possible options to manage the informed consent process in an appropriate, practical, and, we believe, ethical way when time is limited.

How parents and practitioners experience research without prior consent (deferred consent) for emergency research involving children with life threatening conditions: a mixed method study

OBJECTIVE

Alternatives to prospective informed consent to enable children with life-threatening conditions to be entered into trials of emergency treatments are needed. Across Europe, a process called deferred consent has been developed as an alternative. Little is known about the views and experiences of those with first-hand experience of this controversial consent process. To inform how consent is sought for future paediatric critical care trials, we explored the views and experiences of parents and practitioners involved in the CATheter infections in CHildren (CATCH) trial, which allowed for deferred consent in certain circumstances.

DESIGN

Mixed method survey, interview and focus group study.

PARTICIPANTS

275 parents completed a questionnaire; 20 families participated in an interview (18 mothers, 5 fathers). 17 CATCH practitioners participated in one of four focus groups (10 nurses, 3 doctors and 4 clinical trial unit staff).

SETTING

12 UK children's hospitals.

RESULTS

Some parents were momentarily shocked or angered to discover that their child had or could have been entered into CATCH without their prior consent. Although these feelings resolved after the reasons why consent needed to be deferred were explained and that the CATCH interventions were already used in clinical care. Prior to seeking deferred consent for the first few times, CATCH practitioners were apprehensive, although their feelings abated with experience of talking to parents about CATCH. Parents reported that their decisions about their child's participation in the trial had been voluntary. However, mistiming the deferred consent discussion had caused distress for some. Practitioners and parents supported the use of deferred consent in CATCH and in future trials of interventions already used in clinical care.

CONCLUSIONS

Our study provides evidence to support the use of deferred consent in paediatric emergency medicine; it also indicates the crucial importance of practitioner communication and appropriate timing of deferred consent discussions.

How experience makes a difference: practitioners' views on the use of deferred consent in paediatric and neonatal emergency care trials

BACKGROUND

In 2008 UK legislation was amended to enable the use of deferred consent for paediatric emergency care (EC) trials in recognition of the practical and ethical difficulties of obtaining prospective consent in an emergency situation. However, ambiguity about how to make deferred consent acceptable to parents, children and practitioners remains. In particular, little is known about practitioners' views and experiences of seeking deferred consent in this setting.

METHODS

As part of a wider study investigating consent methods in paediatric emergency care trials (called CONNECT), a 20 item online questionnaire was sent by email inviting practitioners (doctors and nurses) who were involved in talking with families about children's and young people's (aged 0-16 years) participation in UK EC trials. To ensure those with and without experience of deferred consent were included, practitioners were sampled using a combination of purposive and snowball sampling methods. Simple descriptive statistics were used to analyse the quantitative data, whilst the constant comparative method was used to analyse qualitative data. Elements of a symbiotic empirical ethics approach was used to integrate empirical evidence and bioethical literature to explore the data and draw practice orientated conclusions.

RESULTS

Views on deferred consent differed depending upon whether or not practitioners were experienced in this consent method. Practitioners who had no experience of deferred consent reported negative perceptions of this consent method; these practitioners were concerned about the impact that deferred consent would have upon the parent-practitioner relationship. In contrast, practitioners experienced in deferred consent described how families had been receptive to the consent method, if conducted sensitively and in a time appropriate manner. Experienced practitioners also described how deferred consent had improved recruitment, parental decision-making capacity and parent-practitioner relationships in the emergency care setting.

CONCLUSIONS

The views of practitioners with first-hand experience of deferred consent should be considered in the design and ethical review of future paediatric EC trials; the design and ethical review of such trials should not solely be informed by the beliefs of those without experience of using deferred consent. Further research involving parents and children is required to inform practitioner training and normative guidance on the use and appropriateness of deferred consent in emergency settings.

'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.