Evaluation of a closed loop-blood sampling system in the intensive care: a pilot randomised controlled trial.

Participants in this group will receive a closed system for blood sampling attached to their arterial catheter (AC) and infusing 0.9% Sodium Chloride to keep vessel open. All arterial blood gas samples will be sampled using 1.5mL primed syringe (Beckton Dickinson and Company). All laboratory test blood samples will be drawn from the CS by the attending ICU nurse as in normal for ICU scope of practice with the use of small volume blood collection tubes using the following procedure: Drawing the clearing volume • Turn the handle on the sampling site into the prime/clear position. Release plunger latch and smoothly draw back on the reservoir plunger until the plunger stops at its 12ml volume capacity. (Recommended draw rate is 1 second for each ml). • Close the shut-off valve by turning the handle perpendicular to the tubing. • Decontaminate the sampling port with SoluPrep™ Antiseptic wipe (3M™). Ensure plunger is depressed to the bottom of reservoir. Connect the syringe to sampling site. • Slowly draw the blood sample. • Remove the syringe from the sampling site. • Open the shut-off valve by turning the handle parallel to tubing. • Slowly, smoothly, and evenly, reinfuse the clearing volume. (Recommended infusion rate is 1 second for each ml). • Flush the VAMP Plus system by pulling the Snap-Tab on the TruWave transducer and disinfect and remove any excess blood from the sample port with SoluPrep™ Antiseptic wipe (3M™). Afterwards, turn the handle on the sample site back to the pressure monitoring position. • All blood samples, with the exception of arterial blood gas (ABG) tests and peripheral blood cultures, will be taken using small volume blood collection tubes. Small volume blood collection tube volumes are as follows: EDTA 2 mL, SST 3.5 mL and Citrate 1.8 ml; total 7.3 mL for full blood count, Chem20 and coagulation screen tests. • ABGs and peripheral blood culture tests will be sampled as per the RBWH ICS standard procedure (as per usual control practice). • Throughout the entire process, no parts of the arterial catheter system will be removed and the system is completely closed. Nurses will be performing the collection of blood samples in both study arms in line with normal practice as a Critical Care Nurse. Following complete education and orientation to intervention system. Weekly observation of blood sampling practice will be conducted by the Research Nurse throughout the study to monitor practice and protocol fidelity.Blood collection time varies depending on number of tests ordered for e.g. collection of a single arterial blood gas (ABG) may take 2-3 mins; collection of multiple blood samples (Full Blood Count, Urea and Electrolytes, Liver function Tests or even drug assays and Blood culturing) would take longer 5-10 minutes.