Improving Patient Outcomes: 2017 Winning Abstract
To bleed or not to bleed?
Reducing the risk of iatrogenic anaemia in critically ill patients
M. Mushkbar & K. Harrison
University Hospital Coventry and Warwickshire, Coventry, United Kingdom
Critically ill patients are at a significant risk of developing anaemia and receiving a blood transfusion. Improving blood sampling techniques and finding the balance between monitoring an extremely vulnerable group of patients and not over testing is a challenge.
Our aim was to ascertain the amount of blood loss arising from laboratory sampling and Arterial Blood Gas (ABG) in patients on our Cardiothoracic Critical Care Unit (CCCU).
We conducted a survey of blood sampling of 40 consecutive patients on our CCCU in October 2016 who had a minimum length of stay of 24 hours. Standard fill bottles were replaced with reduced fill bottles with smaller filling volumes for coagulation (2ml versus 3ml), full blood count (2ml versus 4ml), biochemistry (2.5 ml versus 5ml) and transfusion samples (4ml versus 6ml). For each patient we recorded the duration of stay on the unit, total number and type of blood samples taken including samples for ABG and the blood volume waste due to line discard for ABG purposes.
The median length of stay was 3 days (range 1-8). The median total volume of blood used for sampling purposes was 101ml (range 16ml -433ml) per patient stay. The median volume of blood used for laboratory tests was 14ml (range 0ml to 54ml). Bottle volumes indicate a 50% reduction compared to standard size bottles. ABGs accounted for 85%of the total volume of blood sampled per patient. Of the 101ml drawn, 70ml median (range 8ml - 313ml) was discarded at the bedside during ABG sampling.
In summary, a significant volume of blood, up to the equivalent of half a unit of blood can be sampled per stay on the CCCU. Simple measures such as implementation of reduced fill bottles have reassuringly reduced the total volume of blood sampled for laboratory tests by nearly half.
As part of patient blood management initiatives we are implementing reduced fill sample tubes trust-wide. We are also investigating the use of in-line blood conservative devices to minimise loss during ABG measurement. We suggest use of blood tests when clinically appropriate rather than universally as part of unit routine.
