While hospital critical care units are renowned for their valiant life-saving efforts involving the sickest of patients, there has been growing recognition of the potentially preventable hazards involved in such intensive care, with a particular focus on hospital-caused infections or medication errors.

The problems identified in the recent Hopkins study, however, were errors of omission -- "not something you did, but something you didn't do," said Winters, a professor of critical care medicine. Had the diagnosis been made in a timely manner, he noted, patient treatment might have been changed and lives potentially saved.

The commonest missed diagnoses identified in the study were heart attack; pulmonary embolism (artery blockage in the lungs); pneumonia; and a deadly fungal condition called aspergillosis that attacks patients with weakened immune systems. Together, they accounted for about one-third of the illnesses that doctors failed to detect in the ICU patients. Misdiagnosis of infections and vascular problems, such as heart attack and stroke, accounted for about three-fourths of the fatal errors.

These findings are especially surprising in light of the fact that the patients in intensive care units are the most monitored, tested, and examined patients in the hospital. "These patients are under a microscope, and yet clinicians still missed these diagnoses," Winters said. Identifying some of the commonest causes of misdiagnosis provides crucial clues for improving ICU diagnosis and treatment, with potentially life-saving results. "This is an area that has received little attention and little funding," he said.

The ICU unit itself presents an intensely challenging environment, Winters said, in which clinicians "are bombarded with more than 7,000 independent pieces of information each day," creating the potential for missing critical signs of an unrecognized deadly medical condition in a patient who is already critically ill.

Because the study focused on autopsy reports, it did not identify increases in non-lethal complications that patients suffered because of a missed or delayed diagnosis that can be costly, require additional tests and procedures as well as time in the hospital, and potentially reduce quality of life.

Hopkins has long been a leader in patient safety efforts nationwide. An earlier effort focused on the insertion of central lines into patients to introduce drugs and fluids has reduced the incidence of potentially lethal hospital-acquired bloodstream infections by almost 60 percent, he said. The improvements resulted in part from awareness campaigns to increase hospital staff adherence to patient safety regimens involving better teamwork and checklists of best medical practice.

The Hopkins researchers hope that the study, will point toward new strategies for preventing misdiagnosis, including better understanding of the appropriate staffing ratio per critical care patient, as well as cognitive tools and checklists that focus on better detection of the most frequently missed conditions.

In the long run, while new technologies to pinpoint the problems earlier may also be needed, patients don't have to wait for this to happen. "Clearly the human component," Winters said, "how the staff absorbs the information and improved teamwork and communication is crucial too."





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