Kingston Health Sciences Centre (KHSC) is reducing the amount of blood it collects for testing, reducing hospital patient strain and demand on donated blood products.
While bloodwork provides crucial information to help guide treatment, losing too much blood can increase the risk of anemia, a shortage of red blood cells, and blood transfusion.
The new approach is simple: replace standard blood test vials with smaller tubes that draw less blood. These tubes are routinely used for children in hospital, but have never been widely used in adults.
Reducing patient strain
Standard sample tubes take around 3-6 milliliters of blood and, depending on the type or severity of illness, patients could need multiple vials taken several times a day. Only 10% of the blood drawn from patients is needed for testing, with 90% discarded as medical waste.
A critically ill patient in the Intensive Care Unit (ICU), for example, could require three different tests, each requiring a separate tube and a total volume of 9 milliliters of blood to fill all three tubes. Additional factors, like cardiac symptoms, could require another test, bringing the total draw to four vials. Blood work could be done 2-3 times a day, and with three routine tests done each time, the total draw is around 27 milliliters of blood for testing alone. This is compounded by the length of hospital stay.
“It starts to add up quickly, and it can create an unnecessary need for a blood transfusion, an avoidable risk for patients. Losing too much blood can slow recovery and cause complications like anemia. For patients who have lost a lot of blood for laboratory testing, it may also bring them closer to needing a transfusion, which we have to work hard to avoid."
- Dr. Jeannie Callum, Director of Transfusion Medicine for KHSC
A pilot study in KHSC's ICU took place in May 2023 with expanded roll-out to the entire unit in June. By October, all units across all sites were transitioned to the new tubes.
A Canadian study, published in the Journal of the American Medical Association in October, led by Canadian researcher, Dr. Deborah Siegal, found that small-volume blood collection tubes reduce the number of blood transfusions required in intensive care units. It showed that using low volume tubes for 100 patients in critical care would prevent 10 blood transfusions.
What is novel is that KHSC implemented these tubes for adults across the hospital, not just in critical care.
Making the change
“Something like switching one vial for another sounds easy, but that sort of change takes lots of patience and persistence in a system this complex," says Dr. Curtis Oleschuk, Clinical Biochemist with KHSC's pathology and molecular medicine team, and one of the key staff involved in leading this important transition.
The chemistry unit alone performs approximately 1.5 million tests in a year, so the change needed to be compatible with current processes. In addition to guaranteeing that low-volume sample tubes could meet testing needs, they needed to be tested with laboratory robotics to ensure they were compatible with automated processes.
Staff also needed to be trained. The phlebotomy team was the first to trial the tubes and showed that the tubes could be implemented without impact on the blood collection process.
The last piece of the puzzle was supply chain: staff confirmed that vendors could continue to supply the new tubes. They're also are the same price as the standard tubes, meaning patient outcomes could also be improved without additional healthcare costs.
The big picture
In the right situation, a blood transfusion may be a patient's only option, but it carries its own risks.
“A transfusion introduces new potential complications that could hinder rather than help a patient's recovery," says Dr. Callum. “Blood transfusions have numerous risks including triggering heart failure and increasing the risks of infection. Taking less blood for routine testing is a simple way to reduce the risk of transfusion and other complications."
The combination of an aging population needing more transfusions per capita, and more aggressive cancer treatments, has increased the demand for blood transfusion. Every unit of blood not transfused for anemia from blood sample collection makes it available for another patient in need.
KHSC is one of only a handful of hospitals in Canada to move to low-volume blood test tubes across the whole organization for all adult patients, but “small" interventions like this are becoming a necessity in this unprecedented environment. They're helping to reduce the likelihood of a transfusion by drawing less blood for testing, saving those units of blood for a situation when it's the only option.