When Dr. Gilman Allen and his colleagues at the University of Vermont Medical Center (UVMMC) looked for opportunities to reduce resource overuse in the critical care setting, many fingers pointed to one of the most routine practices in intensive care units–daily blood draws to measure oxygen and carbon dioxide levels in mechanically ventilated patients.
The medical center already had a clearly established culture and practice of not routinely giving red blood cell transfusions to stable ICU patients with a certain hemoglobin level, per the Critical Care Societies Collaborative (CCSC) Choosing Wisely recommendation around regular diagnostic tests. But the specialty unit used a significant number of blood sticks to determine carbon dioxide levels in a patient’s blood and then adjust ventilation if necessary.
“Daily blood draws are often done more out of cultural routine than clearly established clinical indications,” said Dr. Allen, Director of Adult Critical Care Services and the Medical Intensive Care Unit at Vermont Medical Center. “They are believed to contribute to excessive blood loss and a potentially avoidable need for transfusion, and often do not lead to significant changes in management. We were hoping to reduce blood loss and improve blood conservation.”
Dr. Allen and his team developed a new protocol for respiratory therapists based on monitoring carbon dioxide levels when a ventilated patient exhales. This common non-invasive measurement of carbon dioxide typically correlates with the amount of carbon dioxide present in arterial blood samples.
The respiratory therapists obtained a baseline measure of blood levels of oxygen and carbon dioxide, also known as arterial blood gas (ABG) sampling, through a blood draw when mechanical ventilation began. they can then adjust a patient’s ventilation by regularly comparing the difference between the carbon dioxide levels during exhalation with the baseline CO2 level. The medical center subsequently removed the option for routine serial ABGs from all order sets, and blood samplings occurred only at the discretion of the ICU treatment team.
There was a 30.8 percent reduction in ABG sampling over a one-year period; and although total mechanical ventilation days declined as well, there was still a drop-off in ABGs per 1,000 ventilation days after the intervention was in place.
“Local routine is often the biggest hurdle to overcome. Any big change in practice requires change in culture, and getting people to adopt change into their daily routine,” said Dr. Allen, noting his efforts to reduce overuse in the ICU represented an evolution in high-value care initiatives started nearly 10 years ago at Vermont Medical under his predecessors.
“If you’re not continually re-engaging staff directly on the units, then it’s difficult to be successful. We had a big educational rollout with house staff and respiratory therapists, but we had to reinforce practice change on a daily basis.”
UVMMC also achieved a significant reduction in daily chest x-rays on ventilated patients in the ICU, another of CCSC’s Choosing Wisely recommendations, which research has shown have low diagnostic value and often negligibly affect clinical decision-making. CCSC includes the American Association of Critical-Care Nurses, the American College of Chest Physicians, the American Thoracic Society and the Society of Critical Care Medicine.
Dr. Allen and his team educated ICU staff about the low value of daily chest x-rays, removed the “daily option” from the EMR order system, and added a query to the daily rounding checklist to prompt an order when clinically warranted. Over a two-year period, the ICU did about 2,000 fewer chest x-rays on ventilated patients
Changing practice “takes frequent and nonjudgmental reminders to healthcare providers, and leading by example, typically by being an early adopter to illustrate the benefits of change to others,” said Dr. Allen.