Prolonged use of intravenous administration sets: a randomised controlled trial.

Abstract

The purpose of this research study was to improve the nursing care of intravenous

catheters by providing evidence on the effects of prolonged duration of intravenous

administration set use.

Intravenous therapy is a vital part of modern health care. However, its invasive nature

can result in infection, with high associated morbidity and mortality. The highest infection rates are displayed in intensive care patients with central venous catheters. The duration of intravenous administration set use may have an impact on infection rates,however the current practice usage and the optimum duration of use is unknown. Previous studies of central venous catheters have reported equal infection rates with 1 to 4 days of administration set use; however few patients have been evaluated with

administration sets used beyond this time. Previous research has been limited by the

inadequacy of available definitions for Catheter-Related Infection.

A prospective, randomised, controlled clinical trial was performed to assess the infection risk of using administration sets for prolonged periods. In the developmental phase prior to the clinical trial; definitions of Catheter-Related Bloodstream Infection (CRBSI) were developed; a nursing practice survey was undertaken to establish the current duration of administration set use; and laboratory experiments were executed to assess the impact of prolonged use on administration set physical integrity and

performance.

Central venous catheters were randomised to have their administration sets used for 4

days (n = 203) or 7 days (n = 201).

Percutaneous central venous catheters were enrolled into the study from two adult

intensive care units at a metropolitan, tertiary-referral, teaching hospital. Catheters were

multiple-lumen, chlorhexidine-gluconate and silver-sulphadiazine coated lines, both inserted and removed in the intensive care unit.

Catheters were cultured for microbial colonisation on removal using the Maki roll-plate

technique. Patients were assessed for CRBSI using the developed definitions consisting

of categories: definite, probable (type I and II), possible and absent. Prior to the clinical

trial, a practice survey questionnaire was administered, and laboratory experimentation

was performed.

Normality of distribution for continuous variables was assessed using the Kolmogorov-

Smirnov statistic. The distribution between groups of variables considered risk factors

for Catheter-Related Infection were tested to assess for bias using Chi-square and T-test.

Logistic regression modelling was performed to analyse the influence of potentially

confounding variables. The incidence of catheter colonisation and CRBSI was tested between groups using Kaplan-Meier survival curve with Log-rank test. Paired T-tests were performed to test for difference in programmed and delivered volumes of

administration sets. A general linear model (ANOVA)± a Scheffe post hoc test to isolate difference was fitted to the standardised values of delivered volumes to determine the effects of day of measurement and volume delivery rate on the accuracy of volume delivery.

There were 10 colonised tips in the intervention group and 19 in the control group. This

difference was not statistically significant (Kaplan Meier survival analysis, Log Rank =

0.87, df = 1, p = 0.35). There were 3 cases of CRBSI per group and the difference in survival from CRBSI was not statistically significant (Kaplan Meier with Log Rank test, p = 0.86). The pre-clinical trial phases of the research programme established that current clinical practice was 3 to 7-day use of administration sets; that administration sets were physically intact and delivered clinically accurate volumes after 7 days of use; and developed useful definitions of CRBSI.

Prolonged intravenous administration set use of 7 days was found to have no significant

impact on patient infection indicators or physical performance of the sets. This finding is

congruent with previous research and trends in current clinical practice.

In conclusion, the research findings support the use of intravenous administration sets

for 7 days.