Effect of a training programme on blood culture contamination rate in critical care

Blood culture contamination can occur from extraction to processing; its rate should not exceed 3%.

OBJECTIVE

To evaluate the impact of a training programme on the rate of contaminated blood cultures after the implementation of sample extraction recommendations based on the best evidence.

METHOD

Prospective before-after study in a polyvalent intensive care unit with 18 beds. Two phases were established (January-June 2012, October 2012-October 2015) with a training period between them. Main recommendations: sterile technique, surgical mask, double skin disinfection (70° alcohol and 2% alcoholic chlorhexidine), 70° alcohol disinfection of culture flasks and injection of samples without changing needles. Including all blood cultures of patients with extraction request.

VARIABLES

demographic, severity, pathology, reason for admission, stay and results of blood cultures (negative, positive and contaminated). Basic descriptive statistics: mean (standard deviation), median (interquartile range) and percentage (95% confidence interval). Calculated contamination rates per 100 blood cultures extracted. Bivariate analysis between periods.

RESULTS

Four hundred and eight patients were included. Eight hundred and forty-one blood cultures were taken, 33 of which were contaminated. In the demographic variables, severity, diagnosis and stay of patients with contaminated samples, no differences were observed from those with uncontaminated samples. Pre-training vs post-training contamination rates: 14 vs 5.6 per 100 blood cultures extracted (P=.00003).

CONCLUSION

An evidence-based training programme reduced the contamination of samples. It is necessary to continue working on the planning of activities and care to improve the detection of pollutants and prevent contamination of samples.

[Genetic determinants of acute renal damage risk and prognosis: a systematic review]

INTRODUCTION

Acute renal damage (ARD) is a frequent syndrome in hospitalized patients. It is well accepted that ARD susceptibility and outcome are related to environmental risk factors and to the patient premorbid status. Recently, host factors have also been recognized as important in ARD predisposition and evolution.

OBJECTIVE

To analyze genetic influences related to the risk and severity of ARD.

DATA SOURCE

MEDLINE search.

SELECTION OF STUDIES

articles published in English or Spanish between 1/1/1995 and 31/5/2011, analyzing the association between genic polymorphisms and (a) ARD susceptibility in patients versus healthy controls or within groups of patients; or (b) ARD severity.

EXCLUSION CRITERIA

studies published only in abstract form, case reports or including patients less than 16 years of age, on chronic dialysis or having received a renal transplant.

DATA EXTRACTION

at least one investigator analyzed each manuscript and collected the information using a predefined form.

RESULTS

We identified 12 relevant studies that included 4835 patients. Eleven genes showed polymorphisms related to ARD susceptibility or severity. They were related to cardiovascular regulation (ACE I/D, eNOS, FNMT and COMT), inflammatory response (TNFα, IL10, IL6, HIP-1α, EPO), oxidative stress (NAPH oxidase) and lipid metabolism (APO E). Only APO E, ACE and AT1 receptor have been analyzed in more than one study.

CONCLUSION

ARD susceptibility and severity is influenced by genetic factors, which are multiple and involve different physiopathological mechanisms.