Prospective clinical study on the incidence of catheter-related complications in a neurological intensive care unit: 4 years of experience

INTRODUCTION

Over the past decades, significant efforts have been made to reduce early and late catheter-related complications in critically ill patients, using approaches based on bundles of evidence-based interventions.

METHODS

In this prospective clinical study, the authors evaluated the incidence of catheter-related complications in their neuro-intensive care unit during a 4-year period, adopting systematically the GAVeCeLT bundles for the insertion and management of all central venous access devices: centrally inserted central catheters (CICCs), peripherally inserted central catheters (PICCs) and femorally inserted central catheters (FICCs). All early/immediate and late complications were recorded.

RESULTS

On 486 central lines (328 CICCs, 149 PICCs and 9 FICCs), the only clinically relevant early/immediate complication was primary tip malposition (1%). In regards late infective complications, the authors did not record any case of catheter-related bloodstream infection; though, they observed one case of central line associated blood stream infection (one CICC; 0.14/1000 catheter days), and 15 cases of catheter colonization (12 CICCs and 3 PICCs; 2.09 episodes/1000 catheter days). Late non-infective complications were few: 14 accidental dislodgments (2.9%), 18 irreversible lumen occlusions (3.7%), and no episodes of symptomatic catheter-related thrombosis or tip migration.

CONCLUSION

The systematic adoption of the GAVeCeLT bundles for CVAD insertion and maintenance was associated with a minimization of catheter-related complications. The strict adherence to the recommendations included in these bundles was the major determinant for clinical success.

Understanding the diagnosis of catheter-related bloodstream infection: real-time monitoring of biofilm growth dynamics using time-lapse optical microscopy

Background

The differential time to positivity (DTTP) technique is recommended for the conservative diagnosis of catheter-related bloodstream infection (C-RBSI). The technique is based on a 120-minute difference between microbial growth in blood drawn through the catheter and blood drawn through a peripheral vein. However, this cut-off has failed to confirm C-RBSI caused by Candida spp. and Staphylococcus aureus.

Objective

We hypothesized that the biofilm of both microorganisms disperses faster than that of other microorganisms and that microbial load is rapidly equalized between catheter and peripheral blood. Therefore, our aim was to compare the biofilm dynamics of various microorganisms.

Methods

Biofilm of ATCC strains of methicillin-resistant Staphylococcus epidermidis, methicillin-susceptible S. aureus, Enterococcus faecalis, Escherichia coli and Candida albicans was grown on silicon disks and analyzed using time-lapse optical microscopy. The time-lapse images of biofilms were processed using ImageJ2 software. Cell dispersal time and biofilm thickness were calculated.

Results

The mean (standard deviation) dispersal time in C. albicans and S. aureus biofilms was at least nearly 3 hours lower than in biofilm of S. epidermidis, and at least 15 minutes than in E. faecalis and E. coli biofilms.

Conclusion

Our findings could explain why early dissemination of cells in C. albicans and S. aureus prevents us from confirming or ruling out the catheter as the source of the bloodstream infection using the cut-off of 120 minutes in the DTTP technique. In addition, DTTP may not be sufficiently reliable for E. coli since their dispersion time is less than the cut-off of 120 minutes.

Diagnostic and Therapeutic Utility of Positive Intravascular Catheter Tip Cultures

This study evaluated the performance and clinical utility of performing intravascular catheter tip cultures (CTC). A retrospective chart review was conducted over a 2.5 year period on all patients who demonstrated growth of at least one organism on CTC. There were a total of 391 CTC performed. 88 (23%) grew at least one organism, while 303 (77%) had no growth. Of the positive CTC, 81 (92%) had blood cultures (BC) collected within 14 days, whereas 7 (8%) did not. Of the positive CTC with BC, 67 (83%) were BC-positive, whereas 14 (17%) were negative. For cases with growth on both CTC and BC, the organisms identified were concordant for 46 (69%) cases and discordant for 21 (31%). Of the concordant cases, 43 (93%) were clinically considered to be bacterial bloodstream infections that were secondary to a catheter infection. For all of the positive CTC cases total, there was no change in the antibiotics or management, with the exceptions of 2 out of 88 (2%) cases. Catheters were removed and cultured for an average of 38.6 h (range: -98 to 288 h) after positive BC results were available. Most CTC are negative, and for the CTC that are positive, most are concordant with BC results. CTC results are generally only available several days after positive BC results are known. The CTC results did not alter the antibiotic therapy or management, with the exceptions of rare cases. As such, this study concludes that CTC do not contribute diagnostic or therapeutic value. Therefore, current guidelines by the Infectious Diseases Society of America on catheter-related bloodstream infection diagnosis should be revised to exclude CTC collection. IMPORTANCE In patients with intravascular catheters who are febrile or have positive blood cultures and no other obvious sources of infection, catheter tip cultures are often obtained to evaluate potential catheter-related bloodstream infections. However, previous studies reported that the management of catheter-related bloodstream infection cases is entirely based on blood culture growth and susceptibilities and that catheter tip cultures have low diagnostic positive predictive value. Our study represents the largest contemporary evaluation that includes chart reviews on all positive catheter tip culture cases. We found that positive cultures led to no changes in antibiotics or management, except for in two cases. Furthermore, 92% of positive catheter tip cultures were associated with blood culture collections, and catheter cultures were generally available only several days after the blood culture results were known. Thus, our study supports the claim that positive catheter tip cultures add limited diagnostic and therapeutic value in suspected catheter-related bloodstream infections.

Diagnostic usefulness of differential time to positivity in neutropenic cancer patients with suspected catheter-related candidemia

Methods for distinguishing catheter-related candidemia (CRC) from non-CRC before catheter removal remain limited. We thus evaluated the diagnostic performance of differential time to positivity (DTP) to diagnose CRC in neutropenic cancer patients with suspected CRC. Of the 35 patients enrolled, 15 (43%) with CRC (six definite and nine probable) and 17 (49%) with non-CRC were finally analyzed. Based on the receiver operating characteristic curve, the optimal cutoff value of DTP for diagnosing CRC was ≥1.45 hours with the sensitivity 80% (95% confidence interval [CI], 51-95) and specificity 100% (95% CI, 80-100), respectively.

Time to and differential time to blood culture positivity for assessing catheter-related yeast fungaemia: A longitudinal, 7-year study in a single university hospital

BACKGROUND

Time to positivity (TTP) and differential time to positivity (DTTP) between central and peripheral blood cultures are commonly used for bacteraemia to evaluate the likelihood of central venous catheter (CVC)-related bloodstream infection. Few studies have addressed these approaches to yeast fungaemia.

OBJECTIVES

This study aimed to evaluate TTP and DTTP to assess CVC-related yeast fungaemia (CVC-RYF).

PATIENTS/METHODS

We retrospectively analysed the results from 105 adult patients with incident fungaemia, with CVC removed and cultured, collected from 2010 to 2017. The bottles were incubated in a BioMérieux BacT/ALERT 3D and kept for at least 5 days.

RESULTS

Of the 105 patients included, most were oncology patients (85.7%) and had of long-term CVC (79.6%); 32 (30.5%) had a culture-positive CVC (defined as CVC-RYF) with the same species as in blood culture, and 69.5% had culture-negative CVC (defined as non-CVC-RYF, NCVC-RYF). Candida albicans represented 46% of the episodes. The median TTP was statistically different between CVC-RYF and NCVC-RYF (16.8 hours interquartile range (IQR) [9.7-28.6] vs 29.4 hours [IQR 20.7-41.3]; P = .001). A TTP <10 hours had the best positive likelihood ratio (21.5) for CVC-RYF, although the sensitivity was only 28%. DTTP was available for 52 patients. A DTTP >5 hours had a sensitivity of 100% and a specificity of 71% for CVC-RYF.

CONCLUSIONS

Since the median TTP was 17 hours and the most performing DTTP >5 hours, these delays are too long to take a decision in the same operational day. More rapid methods for detecting infected catheters should be tested to avoid unnecessary CVC withdrawal.

Importance of blood cultures from peripheral veins in pediatric patients with cancer and a central venous line

BACKGROUND

When an infection is suspected in a child with cancer and a central venous line (CVL), cultures are often only obtained from the CVL and not from a peripheral vein (PV). This study was undertaken to evaluate the importance of concomitant blood cultures from the CVL and a PV.

PROCEDURE

Clinical data and the results of all cultures taken concomitantly from the CVL and a PV were registered prospectively in children admitted with fever from April 2008 to December 2012 at the Department of Pediatrics at Aarhus University Hospital Skejby.

RESULTS

During the study period 654 paired cultures obtained from the CVL and from a PV within two hour of each other were included. A true bloodstream infection (BSI) was registered in 112 episodes. In 20 (17%) out of 112, true BSI growth of a microorganism was detected only in the culture from a PV including seven cases of Escherichia coli and three cases of Staphylococcus aureus. In 52 episodes the same microorganism was cultured from both the CVL and a PV. Twenty-four of these episodes were classified as catheter-related bloodstream infections (CRBSI) using differential time to positivity. In total, 64 (57%) of all true BSI were defined as CRBSI.

CONCLUSIONS

Blood cultures should be obtained from a PV in addition to cultures from CVL at the onset of fever in pediatric patients with cancer in order to maximize the findings of true BSIs. The frequency of CRBSI may be over-estimated if blood cultures are drawn from CVL only.