Randomised, controlled, feasibility trial comparing vasopressor infusion administered via peripheral cannula versus central venous catheter for critically ill adults: A study protocol.

BACKGROUND: When clinicians need to administer a vasopressor infusion, they are faced with the choice of administration via either peripheral intravenous catheter (PIVC) or central venous catheter (CVC). Vasopressor infusions have traditionally been administered via central venous catheters (CVC) rather than Peripheral Intra Venous Catheters (PIVC), primarily due to concerns of extravasation and resultant tissue injury. This practice is not guided by contemporary randomised controlled trial (RCT) evidence. Observational data suggests safety of vasopressor infusion via PIVC. To address this evidence gap, we have designed the "Vasopressors Infused via Peripheral or Central Access" (VIPCA) RCT. METHODS: The VIPCA trial is a single-centre, feasibility, parallel-group RCT. Eligible critically ill patients requiring a vasopressor infusion will be identified by emergency department (ED) or intensive care unit (ICU) staff and randomised to receive vasopressor infusion via either PIVC or CVC. Primary outcome is feasibility, a composite of recruitment rate, proportion of eligible patients randomised, protocol fidelity, retention and missing data. Primary clinical outcome is days alive and out of hospital up to day-30. Secondary outcomes will include safety and other clinical outcomes, and process and cost measures. Specific aspects of safety related to vasopressor infusions such as extravasation, leakage, device failure, tissue injury and infection will be assessed. DISCUSSION: VIPCA is a feasibility RCT whose outcomes will inform the feasibility and design of a multicentre Phase-3 trial comparing routes of vasopressor delivery. The exploratory economic analysis will provide input data for the full health economic analysis which will accompany any future Phase-3 RCT.

Sodium chloride or plasmalyte-148 for patients presenting to emergency departments with diabetic ketoacidosis: A nested cohort study within a multicentre, cluster, crossover, randomised, controlled trial.

OBJECTIVE: To test the hypothesis that fluid resuscitation in the ED with plasmalyte-148 (PL) compared with 0.9% sodium chloride (SC) would result in a lower proportion of patients with diabetic ketoacidosis (DKA) requiring intensive care unit (ICU) admission. METHODS: We performed a prespecified nested cohort study at two hospitals within a cluster, crossover, open label, randomised, controlled trial comparing the effects of PL versus SC as fluid therapy for patients who presented to the ED with DKA. All patients presenting within a fixed recruitment period were included. The primary outcome was the proportion of patients admitted to ICU. RESULTS: Eighty-four patients were enrolled (SC n = 38, PL n = 46). The SC group had a lower median pH on admission (SC: 7.09 [interquartile range (IQR) 7.01-7.21], PL: 7.17 [IQR 6.99-7.26]). The median volume of intravenous fluids administered in ED was 2150 mL (IQR 2000-3200 mL; SC) and 2200 mL (IQR 2000-3450; PL); respectively. A higher proportion of patients in the SC group, 19 (50%), was admitted to ICU compared with PL group, 18 (39.1%); however, after adjustment for pH at presentation and diabetes type in a multivariable logistic regression model, the PL group did not have a significantly different rate of ICU admission compared with the SC group (odds ratio for ICU admission 0.73, 95% confidence interval 0.13-3.97, P = 0.71). CONCLUSION: Patients with DKA treated with PL compared with SC in the EDs had similar rates of requiring ICU admission.

Molecular survey for mosquito-transmitted viruses: detection of Tensaw virus in north central Florida mosquito populations.

A bunyavirus surveillance was performed in 2,600 pools consisting of 45,728 mosquitoes collected in north-central Florida from May 2006 to April 2007. Fifteen mosquito pools were found to be virus-positive from the total 2,600 mosquito pools tested (0.6% infection rate), which resulted in a minimum infection rate of 0.33 per 1,000 mosquitoes. Sequence data identified the virus to be Tensaw virus, a member of the Bunyaviridae family. All the virus-positive samples were obtained from pools collected from May to October 2006, in 3 of the 4 major locations studied, revealing the presence of Tensaw virus in north-central Florida mosquito populations in 2006.

Tensaw virus genome sequence and its relation to other Bunyaviridae.

Tensaw virus (TSV) belongs to the genus Orthobunyavirus within the Bunyaviridae family. Although TSV does not cause hemorrhagic fever as some other members of its family, serological studies have shown that serum from Florida residents react against TSV indicating viral infection in humans. In this study, the three RNA genome segments of a TSV isolated from Anopheles crucians mosquitoes collected in North Central Florida in 2006 and a TSV isolate obtained from the CDC, Fort Collins, were sequenced and compared to other Bunyaviridae. The placement of the TSVs within the Bunyamwera serogroup was confirmed by phylogenetic analysis of the inferred amino acid (aa) sequence of proteins coded by each of the RNA segments separately as well as by the combined tree of the same three inferred proteins. The N terminal glycoprotein (Gn) encoded by the M segment contained the 18 conserved Cysteines present in Bunyamwera and California serogroups, the two glycosylation sites, and residues considered potential proteolytic cleavage sites conserved in other Bunyaviridae. The TSV L protein displayed all the strictly conserved amino acids in the four conserved regions known to be catalytically active for the RNA dependent RNA polymerase transcriptase and replicase activities. The amino acid conservation between the two TSV viral isolates was 100, 99.4, and 99.6% for the S, M, and L segments, respectively.