Kaiser Permanente study finds doctors use factors beyond risk stratification tools to determine if a patient can safely be treated at home
By Sue Rochman
Most patients who develop a blood clot in their lungs — an acute pulmonary embolism — are seen in the emergency department, where a physician must determine if they should be hospitalized or can be safely managed at home. A new Kaiser Permanente study found that patients who have a high heart rate or blood clots involving both lungs are more likely to be seen as high risk and subsequently hospitalized, even if they are categorized as low risk on a commonly used risk assessment tool.
“Not all patients who appear to be at low risk for bad outcomes are good candidates for home care,” said first author Scott Casey, MD, MS, a delivery science fellow at the Kaiser Permanente Division of Research and an emergency physician with The Permanente Medical Group. “In our study, we looked at a number of factors that a physician might consider in determining which low-risk patients might benefit from hospitalization. We found that emergency physicians may perceive patients with higher heart rates or blood clots in both lungs to be at higher risk and recommend that they be hospitalized.”
The study, published in Annals of Emergency Medicine, included 461 adults with a pulmonary embolism evaluated as having a low risk of dying from their blood clot on the risk assessment score. All patients were seen at one of Kaiser Permanente Northern California’s 21 emergency departments over a 13-month period. About 60% of the low-risk patients studied were hospitalized, often because they had certain high-risk attributes not accounted for by conventional risk assessment tools. The 2 most common reasons were a high heart rate or blood clots in both lungs.
“The study confirms the important role physician judgement has in deciding who needs to be hospitalized,” said senior author David Vinson, MD, an adjunct investigator at the Division of Research and an emergency physician with The Permanente Medical Group. “It also illustrates that doctors know that risk stratification tools can be helpful, but at times they can be incomplete. Our emergency department physicians are experienced in outpatient pulmonary embolism management and can draw on that experience to supplement a risk tool if needed when deciding on patient care.”
The study confirms the important role physician judgement has in deciding who needs to be hospitalized.
— David Vinson, MD
A previous study co-authored by Vinson and Casey showed that an electronic clinical decision aid developed at KPNC helped emergency physicians increase the number of low-risk pulmonary embolism patients who could safely avoid hospitalization. The current study builds on these previous efforts by providing insight into the nuance behind hospitalization decisions for these patients.
Kaiser Permanente has been a leader in home management for eligible patients with pulmonary embolism. “This study could only be done at Kaiser Permanente because we have worked so hard to develop a system that allows patients with a pulmonary embolism to safely be treated at home,” said Vinson. “At many hospitals the default is to hospitalize everyone, but our study shows we are very good at deciding who requires hospitalization and who does not.”
The researchers say their study provides valuable insight to other hospital systems interested in implementing a system-wide home management program. “Our study shows that while the risk assessment score is a first step in helping to differentiate high-risk from low-risk patients, hospital systems can expect that there will be a number of patients with a pulmonary embolism who appear to be low risk but are actually not able to be managed safely at home,” said Casey.
The study was funded by The Permanente Medical Group Delivery Science & Applied Research Program.
Co-authors include Lara Zekar, MD, of the University of California, Davis; Madeline J. Somers, MPH, Mary E. Reed, DrPH, of the Division of Research; and Lauren M. Westafer, DO, MPH, of the UMASS Chan Medical School-Baystate.
# # #
About the Kaiser Permanente Division of Research
The Kaiser Permanente Division of Research conducts, publishes and disseminates epidemiologic and health services research to improve the health and medical care of Kaiser Permanente members and society at large. It seeks to understand the determinants of illness and well-being, and to improve the quality and cost-effectiveness of health care. Currently, DOR’s 600-plus staff is working on more than 450 epidemiological and health services research projects. For more information, visit divisionofresearch.kaiserpermanente.org or follow us @KPDOR.