BACKGROUND: Urinary and (peripheral and central) intravenous catheters are widely used in hospitalized patients. However, up to 56% of the catheters do not have an appropriate indication and some serious complications with the use of these catheters can occur. The main objective of our quality improvement project is to reduce the use of catheters without an appropriate indication by 25-50%, and to evaluate the affecting factors of our de-implementation strategy.METHODS: In a multicenter, prospective interrupted time series analysis, several interventions to avoid inappropriate use of catheters will be conducted in seven hospitals in the Netherlands. Firstly, we will define a list of appropriate indications for urinary and (peripheral and central) intravenous catheters, which will restrict the use of catheters and urge catheter removal when the indication is no longer appropriate. Secondly, after the baseline measurements, the intervention will take place, which consists of a kick-off meeting, including a competitive feedback report of the baseline measurements, and education of healthcare workers and patients. Additional strategies based on the baseline data and local conditions are optional. The primary endpoint is the percentage of catheters with an inappropriate indication on the day of data collection before and after the de-implementation strategy. Secondary endpoints are catheter-related infections or other complications, catheter re-insertion rate, length of hospital (and ICU) stay and mortality. In addition, the cost-effectiveness of the de-implementation strategy will be calculated.DISCUSSION: This study aims to reduce the use of urinary and intravenous catheters with an inappropriate indication, and as a result reduce the catheter-related complications. If (cost-) effective it provides a tool for a nationwide approach to reduce catheter-related infections and other complications.TRIAL REGISTRATION: Dutch trial registry: NTR6015 . Registered 9 August 2016.
Matrix-assisted laser desorption/ionisation time of-flight mass spectrometry (MALDI-TOF MS) is a fast and reliable method for the identification of bacteria from agar media. Direct identification from positive blood cultures should decrease the time to obtaining the result. In this study, three different processing methods for the rapid direct identification of bacteria from positive blood culture bottles were compared. In total, 101 positive aerobe BacT/ALERT bottles were included in this study. Aliquots from all bottles were used for three bacterial processing methods, i.e. the commercially available Bruker's MALDI Sepsityper kit, the commercially available Molzym's MolYsis Basic5 kit and a centrifugation/washing method. In addition, the best method was used to evaluate the possibility of MALDI application after a reduced incubation time of 7 h of Staphylococcus aureus- and Escherichia coli-spiked (1,000, 100 and 10 colony-forming units [CFU]) aerobe BacT/ALERT blood cultures. Sixty-six (65%), 51 (50.5%) and 79 (78%) bottles were identified correctly at the species level when the centrifugation/washing method, MolYsis Basic 5 and Sepsityper were used, respectively. Incorrect identification was obtained in 35 (35%), 50 (49.5%) and 22 (22%) bottles, respectively. Gram-positive cocci were correctly identified in 33/52 (64%) of the cases. However, Gram-negative rods showed a correct identification in 45/47 (96%) of all bottles when the Sepsityper kit was used. Seven hours of pre-incubation of S. aureus- and E. coli-spiked aerobe BacT/ALERT blood cultures never resulted in reliable identification with MALDI-TOF MS. Sepsityper is superior for the direct identification of microorganisms from aerobe BacT/ALERT bottles. Gram-negative pathogens show better results compared to Gram-positive bacteria. Reduced incubation followed by MALDI-TOF MS did not result in faster reliable identification.
To accelerate differentiation between Staphylococcus aureus and Coagulase Negative Staphylococci (CNS), this study aimed to compare six different DNA extraction methods from 2 commonly used blood culture materials, i.e. BACTEC and Bact/ALERT. Furthermore, we analyzed the effect of reduced blood culture times for detection of Staphylococci directly from blood culture material. A real-time PCR duplex assay was used to compare 6 different DNA isolation protocols on two different blood culture systems. Negative blood culture material was spiked with MRSA. Bacterial DNA was isolated with: automated extractor EasyMAG (3 protocols), automated extractor MagNA Pure LC (LC Microbiology Kit MGrade), a manual kit MolYsis Plus, and a combination between MolYsis Plus and the EasyMAG. The most optimal isolation method was used to evaluate reduced bacterial culture times. Bacterial DNA isolation with the MolYsis Plus kit in combination with the specific B protocol on the EasyMAG resulted in the most sensitive detection of S.aureus, with a detection limit of 10 CFU/ml, in Bact/ALERT material, whereas using BACTEC resulted in a detection limit of 100 CFU/ml. An initial S.aureus load of 1 CFU/ml blood can be detected after 5 hours of culture in Bact/ALERT3D by combining the sensitive isolation method and the tuf LightCycler assay.