Effect of infusion set replacement intervals on catheter-related bloodstream infections (RSVP): a randomised, controlled, equivalence (central venous access device)-non-inferiority (peripheral arterial catheter) trial.

BACKGROUND: The optimal duration of infusion set use to prevent life-threatening catheter-related bloodstream infection (CRBSI) is unclear. We aimed to compare the effectiveness and costs of 7-day (intervention) versus 4-day (control) infusion set replacement to prevent CRBSI in patients with central venous access devices (tunnelled cuffed, non-tunnelled, peripherally inserted, and totally implanted) and peripheral arterial catheters. METHODS: We did a randomised, controlled, assessor-masked trial at ten Australian hospitals. Our hypothesis was CRBSI equivalence for central venous access devices and non-inferiority for peripheral arterial catheters (both 2% margin). Adults and children with expected greater than 24 h central venous access device-peripheral arterial catheter use were randomly assigned (1:1; stratified by hospital, catheter type, and intensive care unit or ward) by a centralised, web-based service (concealed before allocation) to infusion set replacement every 7 days, or 4 days. This included crystalloids, non-lipid parenteral nutrition, and medication infusions. Patients and clinicians were not masked, but the primary outcome (CRBSI) was adjudicated by masked infectious diseases physicians. The analysis was modified intention to treat (mITT). This study is registered with the Australian New Zealand Clinical Trials Registry ACTRN12610000505000 and is complete. FINDINGS: Between May 30, 2011, and Dec, 9, 2016, from 6007 patients assessed, we assigned 2944 patients to 7-day (n=1463) or 4-day (n=1481) infusion set replacement, with 2941 in the mITT analysis. For central venous access devices, 20 (1·78%) of 1124 patients (7-day group) and 16 (1·46%) of 1097 patients (4-day group) had CRBSI (absolute risk difference [ARD] 0·32%, 95% CI -0·73 to 1·37). For peripheral arterial catheters, one (0·28%) of 357 patients in the 7-day group and none of 363 patients in the 4-day group had CRBSI (ARD 0·28%, -0·27% to 0·83%). There were no treatment-related adverse events. INTERPRETATION: Infusion set use can be safely extended to 7 days with resultant cost and workload reductions. FUNDING: Australian National Health and Medical Research Council.

Incidence and risk factors for central venous access device failure in hospitalized adults: A multivariable analysis of 1892 catheters.

BACKGROUND: Central venous access devices (CVADs) allow intravenous therapy, haemodynamic monitoring and blood sampling but many fail before therapy completion. OBJECTIVE: To quantify CVAD failure and complications; and identify risk factors. DESIGNS, SETTINGS, AND PARTICIPANTS: Secondary analysis of multicentre randomised controlled trial including patients aged ≥16 years with a non-tunnelled CVAD (NTCVAD), peripherally-inserted central catheter (PICC) or tunnelled CVAD (TCVAD). Primary outcome was incidence of all-cause CVAD failure (central line-associated bloodstream infection [CLABSI], occlusion, accidental dislodgement, catheter fracture, thrombosis, pain). Secondary outcomes were CLABSI, occlusion and dislodgement. Cox regression was used to report time-to-event associations. RESULTS: In 1892 CVADs, all-cause failure occurred in 10.2% of devices: 49 NTCVADs (6.1%); 100 PICCs (13.2%); 44 TCVADs (13.4%). Failure rates for CLABSI, occlusion and dislodgement were 5.3%, 1.8%, and 1.7%, respectively. Independent CLABSI predictors were blood product administration through PICCs (hazard ratio (HR) 2.62, 95% confidence interval (CI) 1.24-5.55); and in TCVADs, one or two lumens, compared with three to four (HR 3.36, 95%CI 1.68-6.71), intravenous chemotherapy (HR 2.96, 95%CI 1.31-6.68), and diabetes (HR 3.25, 95%CI 1.40-7.57). Independent factors protective for CLABSI include antimicrobial NTCVADs (HR 0.23, 95%CI 0.08-0.63) and lipids in TCVADs (HR 0.32, 95%CI 0.14-0.72). NTCVADs inserted at another hospital (HR 7.06, 95%CI 1.48-33.7) and baseline infection in patients with PICCs (HR 2.72, 95%CI 1.08-6.83) were predictors for dislodgement. No independent occlusion predictors were found. Modifiable risk factors were identified for CVAD failure, which occurred for 1-in-10 catheters. Strict infection prevention measures and improved CVAD securement could reduce CLABSI and dislodgement risk.

Routine versus clinically indicated replacement of peripheral intravenous catheters: a randomised controlled equivalence trial.

BACKGROUND: The millions of peripheral intravenous catheters used each year are recommended for 72-96 h replacement in adults. This routine replacement increases health-care costs and staff workload and requires patients to undergo repeated invasive procedures. The effectiveness of the practice is not well established. Our hypothesis was that clinically indicated catheter replacement is of equal benefit to routine replacement. METHODS: This multicentre, randomised, non-blinded equivalence trial recruited adults (≥18 years) with an intravenous catheter of expected use longer than 4 days from three hospitals in Queensland, Australia, between May 20, 2008, and Sept 9, 2009. Computer-generated random assignment (1:1 ratio, no blocking, stratified by hospital, concealed before allocation) was to clinically indicated replacement, or third daily routine replacement. Patients, clinical staff, and research nurses could not be masked after treatment allocation because of the nature of the intervention. The primary outcome was phlebitis during catheterisation or within 48 h after removal. The equivalence margin was set at 3%. Primary analysis was by intention to treat. Secondary endpoints were catheter-related bloodstream and local infections, all bloodstream infections, catheter tip colonisation, infusion failure, catheter numbers used, therapy duration, mortality, and costs. This trial is registered with the Australian New Zealand Clinical Trials Registry, number ACTRN12608000445370. FINDINGS: All 3283 patients randomised (5907 catheters) were included in our analysis (1593 clinically indicated; 1690 routine replacement). Mean dwell time for catheters in situ on day 3 was 99 h (SD 54) when replaced as clinically indicated and 70 h (13) when routinely replaced. Phlebitis occurred in 114 of 1593 (7%) patients in the clinically indicated group and in 114 of 1690 (7%) patients in the routine replacement group, an absolute risk difference of 0·41% (95% CI -1·33 to 2·15%), which was within the prespecified 3% equivalence margin. No serious adverse events related to study interventions occurred. INTERPRETATION: Peripheral intravenous catheters can be removed as clinically indicated; this policy will avoid millions of catheter insertions, associated discomfort, and substantial costs in both equipment and staff workload. Ongoing close monitoring should continue with timely treatment cessation and prompt removal for complications. FUNDING: Australian National Health and Medical Research Council.

Microbiological pattern of arterial catheters in the intensive care unit.

BACKGROUND: Intravascular catheter related infection (CRI) is one of the most serious nosocomial infections. Diagnostic criteria include a positive culture from the catheter tip along with blood, yet in many patients with signs of infection, current culture techniques fail to identify pathogens on catheter segments. We hypothesised that a molecular examination of the bacterial community on short term arterial catheters (ACs) would improve our understanding of the variety of organisms that are present in this niche environment and would help develop new methods for the diagnosis of CRI. RESULTS: The whole bacterial community presenting on all ACs was evaluated by molecular methods, i.e., a strategy of whole community DNA extraction, PCR amplification followed by cloning and 16S rDNA sequence analysis. Ten ACs were removed from patients suspected of CRI and 430 clones from 5 "colonised" and 5 "uncolonised" (semi-quantitative method) AC libraries were selected for sequencing and subsequent analysis. A total of 79 operational taxonomic units (OTUs) were identified at the level of 97% similarity belonging to six bacterial divisions. An average of 20 OTUs were present in each AC, irrespective of colonisation status. Conventional culture failed to reveal the majority of these bacteria. CONCLUSIONS: There was no significant difference in the bacterial diversity between the 'uncolonised' and 'colonised' ACs. This suggests that vascular devices cultured conventionally and reported as non infective may at times potentially be a significant source of sepsis in critically ill patients. Alternative methods may be required for the accurate diagnosis of CRI in critically ill patients.

Prospective study of peripheral arterial catheter infection and comparison with concurrently sited central venous catheters.

OBJECTIVE: Peripheral arterial catheters are perceived as having low infective potential compared with other catheters and may be overlooked as a cause of catheter-related bloodstream infection. We aimed to measure colonization and rates of catheter-related bloodstream infection in arterial catheters, to investigate risk factors for arterial catheter colonization, and to compare arterial catheter infection rates with those in concurrently sited and managed central venous catheters. DESIGN: Prospective 24-month cohort study. SETTING: Eight-bed combined general intensive care and high-dependency unit of a 350-bed Australian teaching hospital. PATIENTS: Three hundred twenty-one arterial catheters in 252 adult and pediatric patients were observed for 1,082 catheter days, and 618 central venous catheters in 410 patients were observed for 4,040 catheter days. All catheters were inserted in, or presented to, the intensive care unit. Both arterial catheters and central venous catheters were inserted by trained personnel under aseptic conditions, and management was standardized. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The incidence per 1,000 (95% confidence interval) catheter days of colonization (> or = 15 colonies) and catheter-related bloodstream infection was 15.7 (9.5-25.9) and 0.92 (0.13-6.44) for arterial catheters and 16.8 (13.3-21.3) and 2.23 (1.12-4.44) for central venous catheters. Arterial catheter colonization was not significantly different than that in central venous catheters (hazard ratio, 1.17; 95% confidence interval, 0.41-3.36; p = .77). Arterial catheter colonization increased with dwell time and was similar to central venous catheters over time. Femoral arterial catheters were colonized more often than radial arterial catheters (hazard ratio, 5.08; 95% confidence interval, 0.85, 30.3; p = .075), and colonization was significantly higher when the catheter was inserted in the operating theater or emergency department (hazard ratio, 4.45; 95% confidence interval, 1.42-13.9; p = .01) compared with the intensive care unit. CONCLUSIONS: The incidence of catheter-related bloodstream infection from arterial catheters was low. However, both arterial catheter colonization and rates of catheter-related bloodstream infection were similar to those in concurrently sited and identically managed central venous catheters. By inference, the arterial catheter should be accorded the same degree of importance as the central venous catheter as a potential source of sepsis.

Influence of insertion site on central venous catheter colonization and bloodstream infection rates.

OBJECTIVE: To compare colonization and catheter-related bloodstream infection (CR-BSI) rates among three insertion sites (subclavian, internal jugular, femoral) used for central venous catheter (CVC) placement. DESIGN: Twenty-four-month prospective study, with relative effects analyzed by Cox proportional hazards regression. SETTING: Eight-bed intensive care unit. PATIENTS: Four hundred and ten critically ill patients requiring CVC placement. MEASUREMENTS AND RESULTS: All short-term multi-lumen CVCs, including antimicrobial-coated devices, were studied with management standardized. Six hundred and five CVCs (4,040 catheter days) were analyzed. Colonization and CR-BSI incidence were, respectively, 15.1 (95% CI 13.5-21.0) and 1.8 (95% CI 1.2-4.2) per 1,000 catheter-days. Colonization was higher at the internal jugular (HR 3.64; 95% CI 1.32-10.00; p=0.01) and femoral (HR 5.15; 95% CI 1.82-14.51; p=0.004) sites than at the subclavian site. The femoral site carried a greater risk of being colonized by non-S. epidermidis species than the subclavian and internal jugular sites combined (HR 4.15; 95% CI 1.79-9.61; p=0.001). CVCs inserted in the Department of Emergency Medicine were more colonized than those inserted in the ICU or operating room (HR 2.66; 95% CI 1.27-5.56; p=0.01), and CVCs were less colonized in females than in males (HR 0.49; 95% CI 0.26-0.89; p=0.02). No difference in CR-BSI rates was noted between the three sites. CONCLUSIONS: Colonization was lowest at the subclavian site. Regional differences exist with respect to type of pathogen isolated. Colonization was influenced by insertion location and gender. The incidence of CR-BSI was not different.

Intravascular device administration sets: replacement after standard versus prolonged use in hospitalised patients-a study protocol for a randomised controlled trial (The RSVP Trial).

INTRODUCTION: Vascular access devices (VADs), such as peripheral or central venous catheters, are vital across all medical and surgical specialties. To allow therapy or haemodynamic monitoring, VADs frequently require administration sets (AS) composed of infusion tubing, fluid containers, pressure-monitoring transducers and/or burettes. While VADs are replaced only when necessary, AS are routinely replaced every 3-4 days in the belief that this reduces infectious complications. Strong evidence supports AS use up to 4 days, but there is less evidence for AS use beyond 4 days. AS replacement twice weekly increases hospital costs and workload. METHODS AND ANALYSIS: This is a pragmatic, multicentre, randomised controlled trial (RCT) of equivalence design comparing AS replacement at 4 (control) versus 7 (experimental) days. Randomisation is stratified by site and device, centrally allocated and concealed until enrolment. 6554 adult/paediatric patients with a central venous catheter, peripherally inserted central catheter or peripheral arterial catheter will be enrolled over 4 years. The primary outcome is VAD-related bloodstream infection (BSI) and secondary outcomes are VAD colonisation, AS colonisation, all-cause BSI, all-cause mortality, number of AS per patient, VAD time in situ and costs. Relative incidence rates of VAD-BSI per 100 devices and hazard rates per 1000 device days (95% CIs) will summarise the impact of 7-day relative to 4-day AS use and test equivalence. Kaplan-Meier survival curves (with log rank Mantel-Cox test) will compare VAD-BSI over time. Appropriate parametric or non-parametric techniques will be used to compare secondary end points. p Values of <0.05 will be considered significant. ETHICS AND DISSEMINATION: Relevant ethical approvals have been received. CONSORT Statement recommendations will be used to guide preparation of any publication. Results will be presented at relevant conferences and sent to the major organisations with clinical practice guidelines for VAD care. TRIAL REGISTRATION NUMBER: Australian New Zealand Clinical Trial Registry (ACTRN 12610000505000).

A comparative assessment of two conservative methods for the diagnosis of catheter-related infection in critically ill patients.

PURPOSE: To assess the utility of two in situ techniques, differential time to positivity (DTP) and semiquantitative superficial cultures (SQSC) for diagnosing catheter-related bloodstream infection (CR-BSI) in critically ill adults. METHODS: This was a prospective cohort study in patients with suspected CR-BSI arising from a short-term arterial catheter (AC) or a central venous catheter (CVC). On suspicion of CR-BSI, devices were removed. Blood, skin, catheter tip and hub cultures were taken. Infection rates were compared against the diagnosis of CR-BSI using matched tip and blood cultures. RESULTS: Of 120 episodes of clinically suspected CR-BSI in 101 patients examined, 9 (7.5 %) were confirmed as CR-BSI. Validity values (95 % CI) for the diagnosis of CR-BSI arising from both AC and CVC for DTP were: sensitivity 44 % (15-77 %), specificity 98 % (93-100 %), positive predictive value (PPV) 67 % (24-94 %), negative predictive value (NPV) 96 % (90-98 %), positive likelihood ratio (LR+) 25 (5-117), negative likelihood ratio (LR-) 0.6 (0.3-1.0), diagnostic odds ratio (DOR) 44 (7-258), and accuracy 94 % (92-98 %). Validity values (95 % CI) for SQSC were: sensitivity 78 % (41-96 %), specificity 60 % (50-69 %), PPV 14 % (6-26 %), NPV 97 % (89-99 %), LR+ 1.9 (1.0-2.3), LR- 0.4 (0.1-1.3), DOR 5.1 (1.1-19), and accuracy 61 % (51-69 %). DTP combined with SQSC improved sensitivity and NPV to 100 % whilst the DOR increased to 25.8 (95 % CI 3-454). CONCLUSIONS: CR-BSI can be ruled out by undertaking DTP and SQSC concurrently for both ACs and CVCs with 100 % sensitivity and NPV.

The effect of extubation failure on outcome in a multidisciplinary Australian intensive care unit.

BACKGROUND: A reported association between extubation failure (EF) and increased hospital length of stay and mortality led us to assess outcome of EF in an Australian intensive care unit. DESIGN AND SETTING: Non-interventional cohort study in the intensive care/high dependency unit of a tertiary referral hospital, 2000-2003. METHODS: EF was defined as reintubation within 72 hours of extubation. Causes of EF were determined by review of the clinical notes and prospective record of the EF event. Patients were excluded if they were aged < or = 14 years, self-extubated, were reintubated to replace a defective endotracheal tube, or had been extubated but were returning to the operating theatre. Physiological variables used to calculate severity of illness score were analysed to ascertain correlation with EF. RESULTS: 2761 patients were electively extubated, and 52 (1.8%) fulfilled the criteria for EF. Compared with those successfully extubated, EF patients had a higher 24 h APACHE II score (18.0+/-7.0 [mean+/-SD] v 15.3+/-7.4, P=0.009), significant increases in length of stay in ICU (12.8+/-8.3 v 3.0+/-6.0 days, P<0.001) and hospital (33.5 +/-40.8 v 18.0+/-28.6 days, P<0.001) and tracheostomy rate (38.5% v 3.5%, P<0.001). The commonest cause of EF was excess secretions or aspiration (32%). EF was independently associated with hospital mortality (odds ratio [OR], 2.10; 95% CI, 1.00-4.41; P=0.048) and low serum albumin level on admission (OR, 0.75; 95% CI, 0.55-1.00; P=0.05). Neither aetiology of airway failure (OR, 2.21; 95% CI, 0.56- 8.75; P=0.25) nor time to reintubation (OR, 0.99; 95% CI, 0.97-1.01; P=0.76) were associated with mortality. CONCLUSION: Our findings confirm an increased risk of adverse outcomes for patients with EF. We observed a comparatively low EF rate. Confirmation in similar patient cohorts is required.

Pneumococcal meningitis masquerading as subarachnoid haemorrhage.

A 43-year-old woman taking warfarin for past venous thrombosis presented with 4 days of flu-like symptoms and deterioration in level of consciousness. Computed tomography suggested subarachnoid haemorrhage, and magnetic resonance imaging showed widespread cerebral infarcts. However, these seemed out of proportion to the amount of haemorrhage, and lumbar puncture revealed meningitis caused by Streptococcus pneumoniae.