Density of microbial colonization on external and internal surfaces of concurrently placed intravascular devices

Evaluation of Skin Colonisation And Placement of vascular access device Exit sites (ESCAPE Study)

Background

Skin microorganisms may contribute to the development of vascular access device (VAD) infections. Baseline skin microorganism type and quantity vary between body sites, yet there is little evidence to inform choice of VAD site selection.

Objective

To compare microorganisms present at different body sites used for VAD insertions and understand the effect of transparent dressings on skin microflora.

Methods

The ESCAPE observational study consisted of three phases: (1) skin swabs of four sites (mid-neck, base neck, chest, upper arm) from 48 hospital patients; (2) skin swabs of five body sites (mid-neck, base neck, chest, upper arm, lower arm) from 10 healthy volunteers; and (3) paired skin swabs (n = 72) under and outside of transparent dressings from 36 hospital patients (16 mid/base neck, 10 chest, upper arm). Specimens were cultured for 72 h, species identified and colony-forming units (CFU) counted. Ordinal logistic regression compared CFU categories between variables of interest.

Results

The chest and upper arm were significantly associated with fewer microorganisms compared to neck or forearm (odds ratio [OR] = 0.40, 95% confidence interval [CI] = 0.25-0.65, P < 0.05). CFU levels under transparent dressings were not significantly different from outside (OR = 0.57, 95% CI = 0.22-1.45). Staphylococci were predominant at all sites. Other significant (P < 0.05) predictors of higher CFU count included prolonged hospitalisation and medical/surgical patient status.

Discussion

Skin microorganism load was significantly lower at the upper arm or chest, compared to the mid- or base neck. This may impact VAD site selection and subsequent infection risk.

A survey of the use of arterial catheters in anesthetized dogs and cats: 267 cases

OBJECTIVES

To describe the clinical practice of insertion of arterial catheters in anesthetized dogs and cats, to document complications of arterial catheterization, and to determine risk factors associated with the complications.

DESIGN

Prospective clinical study and retrospective evaluation of medical records.

SETTING

University teaching hospital.

ANIMALS

Dogs (n = 251) and 13 cats anesthetized for clinical procedures with arterial catheters inserted for blood pressure monitoring.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Details of the animal and catheter were collected at the time of anesthesia. On the following day, the catheter site was palpated and observed for abnormalities and the medical records of all animals were reviewed retrospectively for complications. Details of catheter placement were available for 216 catheters: 158 catheters in a dorsal pedal artery, 50 catheters in the median caudal (coccygeal) artery, 6 in the median artery, and 1 each in a cranial tibial and lingual artery. Blood pressure was obtained from 200 catheters, and 12 catheters failed before the end of anesthesia. Postoperative observational data obtained from 112 catheters described a palpable arterial pulse at 73 sites and no pulse at 21 sites. No risk factor for arterial occlusion was identified. No complications resulting from arterial catheterization were noted in the medical records.

CONCLUSIONS

Arterial catheterization resulted in loss of a peripheral pulse postoperatively in 21/94 (22.3%) of animals examined, although no evidence of tissue ischemia was noted in the medical records of any of the patients in this study. These results suggest that insertion of a catheter in the dorsal pedal or coccygeal arteries was not associated with a high risk for complications. However, the course of arterial occlusion postoperatively warrants further investigation.

Use of a policy-driven education program to reduce central line-associated bloodstream infection rates

Central line-associated bloodstream infections (CLABSIs) account for a significant portion of hospital-acquired infections. Current research supports the use of chlorhexidine for site cleansing and staff education programs on infection-control practices to reduce CLABSI rates. This project evaluates the efficacy of implementing site cleaning policies and protocols and formal staff education in reducing CLABSI rates in a critical access hospital. Efficacy was measured by infection rates per 1000 catheter days through a retrospective chart review before and after implementation of a policy and protocol bundle and staff education.

Colonization of stickers used for the identification of intravenous lines: results from an in vitro study

BACKGROUND

Clear differentiation of arterial and intravenous (IV) lines is a safety strategy recommended by the World Health Organization, and signaling stickers attached to IV lines are implemented in many institutions. However, the risk of colonization of the stickers' surface has not been evaluated. Our objective was to assess the colonization rate of stickers used for IV lines identification in an in vitro model using 3 different contamination degrees.

METHODS

A set of 30 stickers used for IV lines identification were exposed to low, medium, and high contamination degrees for up to 15 days. Twice a day, a single manipulator vigorously touched the surface of the stickers simulating the daily handling. Surface cultures of all stickers were performed daily. The microorganisms recovered were counted and identified by phenotypic characteristics.

RESULTS

Colonization occurred after 5 days in low and medium manipulation models and after 3 days in the high manipulation model. Nonadhesive sticker sides were associated with greater significant numbers of colony forming units when manipulation was performed without gloves.

CONCLUSION

Stickers used for the identification of IV lines may become potential reservoirs of catheter colonization. Clinical studies to validate these data and design policies of stickers' changes are required.

Diagnostic accuracy of semi-quantitative and quantitative culture techniques for the diagnosis of catheter-related infections in newborns and molecular typing of isolated microorganisms

BACKGROUND

Catheter-related bloodstream infections (CR-BSIs) have become the most common cause of healthcare-associated bloodstream infections in neonatal intensive care units (ICUs). Microbiological evidence implicating catheters as the source of bloodstream infection is necessary to establish the diagnosis of CR-BSIs. Semi-quantitative culture is used to determine the presence of microorganisms on the external catheter surface, whereas quantitative culture also isolates microorganisms present inside the catheter. The main objective of this study was to determine the sensitivity and specificity of these two techniques for the diagnosis of CR-BSIs in newborns from a neonatal ICU. In addition, PFGE was used for similarity analysis of the microorganisms isolated from catheters and blood cultures.

METHODS

Semi-quantitative and quantitative methods were used for the culture of catheter tips obtained from newborns. Strains isolated from catheter tips and blood cultures which exhibited the same antimicrobial susceptibility profile were included in the study as positive cases of CR-BSI. PFGE of the microorganisms isolated from catheters and blood cultures was performed for similarity analysis and detection of clones in the ICU.

RESULTS

A total of 584 catheter tips from 399 patients seen between November 2005 and June 2012 were analyzed. Twenty-nine cases of CR-BSI were confirmed. Coagulase-negative staphylococci (CoNS) were the most frequently isolated microorganisms, including S. epidermidis as the most prevalent species (65.5%), followed by S. haemolyticus (10.3%), yeasts (10.3%), K. pneumoniae (6.9%), S. aureus (3.4%), and E. coli (3.4%). The sensitivity of the semi-quantitative and quantitative techniques was 72.7% and 59.3%, respectively, and specificity was 95.7% and 94.4%. The diagnosis of CR-BSIs based on PFGE analysis of similarity between strains isolated from catheter tips and blood cultures showed 82.6% sensitivity and 100% specificity.

CONCLUSION

The semi-quantitative culture method showed higher sensitivity and specificity for the diagnosis of CR-BSIs in newborns when compared to the quantitative technique. In addition, this method is easier to perform and shows better agreement with the gold standard, and should therefore be recommended for routine clinical laboratory use. PFGE may contribute to the control of CR-BSIs by identifying clusters of microorganisms in neonatal ICUs, providing a means of determining potential cross-infection between patients.

Insights and advances in multidisciplinary critical care: a review of recent research

The intensive care unit is a work environment where superior dedication is pivotal to optimize patients' outcomes. As this demanding commitment is multidisciplinary in nature, it requires special qualities of health care workers and organizations. Thus research in the field covers a broad spectrum of activities necessary to deliver cutting-edge care. However, given the abundance of research articles and education activities available, it is difficult for modern critical care clinicians to keep up with the latest progress and innovations in the field. This article broadly summarizes new developments in multidisciplinary intensive care, providing elementary information about advanced insights in the field by briefly describing selected articles bundled in specific topics. Issues considered include cardiovascular care, monitoring, mechanical ventilation, infection and sepsis, nutrition, education, patient safety, pain assessment and control, delirium, mental health, ethics, and outcomes research.

Central Line Infections in Repaired Catheters: A Retrospective Review

Background: There have been very few studies conducted to assess the infection risk of repairing a ruptured or broken tunneled central venous access device or a ruptured peripherally inserted central catheter (PICC), a procedure that is fairly common in a certain population of patients.

Methods: In a retrospective review of repairs to both tunneled central venous access devices and PICCs in a large metropolitan health system, 258 medical records were reviewed. During a 4-year period there were 258 repairs, 202 to PICC lines and 56 to tunneled catheters. The system-wide infection database was the source queried to provide evidence for and confirmation of a central line infection. This database is maintained by the infection control team using strict guidelines, reducing inter-rater reliability issues.

Results: The Fisher exact test for proportions was used to compare infection rates between repaired infected and repaired noninfected lines. The infection rate was 5% in repaired catheters and 5.9% in unrepaired catheters (P = 1.00). On average, repaired catheters were in place longer (mean log [time-days in situ] 2.71 vs 2.31). Despite repairs and longer dwell times the repaired catheters did not have a significantly higher rate of infection when compared with unrepaired catheters.

Conclusions: Despite longer dwell times the infection rate for repaired catheters was not statistically significant when compared with unrepaired catheters.