Introduction
Using smaller vials to collect blood samples from people in intensive care could help to prevent risky transfusions. This simple change has the potential to lower the risk of complications and preserve valuable supplies of donated blood.
The Problem with Standard Blood Collection Tubes
Most hospitals around the world use standard blood collection tubes, which withdraw 4 to 6 millilitres of blood, when carrying out tests on people in intensive care units (ICUs). However, most of these tests – which check organ function, clotting, and respiratory health – only require less than 0.5 millilitres of blood. This results in unnecessary large blood samples being taken from ICU patients, leading to substantial blood loss and anaemia.
According to Deborah Siegal at the University of Ottawa, after eight days in intensive care, the amount of blood loss is equivalent to donating a unit of whole blood. Unlike healthy blood donors, ICU patients are often unable to produce more red blood cells to correct for this blood loss.
The Need for Blood Transfusions
Roughly 40% of people in intensive care require blood transfusions due to their illness or injuries. Taking unnecessarily large blood samples further exacerbates the need for transfusions.
Transfusions are expensive, rely on limited supplies of donated blood, and carry the risk of allergic reactions and infections. Transfusions are considered a scarce resource with known harms and cost.
The Study
To address this issue, Deborah Siegal and her colleagues conducted a study that looked at over 27,400 adults who had been in intensive care for at least two days at 25 ICUs across Canada.
For the first six weeks of the study, all of the units used standard blood collection tubes. Every six weeks thereafter, two of the units switched to using smaller vials that collected between 1.8 and 3.5 millilitres of blood.
By analyzing the number of transfusions given, the team found that switching to smaller vials could prevent one transfusion for every 10 people in intensive care compared to using the standard tubes. Over the course of the nearly two-year study, this amounted to saving about 1500 units of blood.
Benefits of Smaller Vials
In addition to reducing the need for transfusions, transitioning to smaller vials also appeared to reduce the risk of anaemia.
Moreover, the smaller tubes did not affect the quality of the blood tests carried out. They are commercially available and have the same cost and physical size as standard-volume tubes, making them compatible with existing lab equipment.
Conclusion
Implementing the use of smaller vials for blood collection in intensive care units has the potential to significantly improve patient safety and conserve donated blood supplies. This simple tweak can minimize the risk of complications associated with transfusions and reduce unnecessary blood loss among ICU patients.
