SAN DIEGO — More than 400,000 cases of pulmonary thromboembolism are missed by doctors every year in the United States.
Over the past few years, it has become clearer why many of those cases are missed and how they could be diagnosed, Dr. Daniel J. Sullivan said at a congress of the American College of Emergency Physicians.
Most often, the patient has an abnormal vital sign that should alert the emergency physician to the possibility of pulmonary embolism (PE), but that single, critical sign sometimes is missed in the complexity of the situation, said Dr. Sullivan, a faculty member in the department of emergency medicine at Rush Medical College, Chicago.
“Syncope, dyspnea, rapid pulse, risk factors such as immobilization—please think PE,” he said. “Every case seems to have good clues.”
Dr. Sullivan presented two cases to illustrate his point. The first case involved a nurse who came into the emergency department (ED) complaining of pain, redness, and possible infection of a wound on her leg.
She had been in a car accident 2 weeks before. In the accident, she sustained two fractures of the arm, a dislocated hip, and a laceration on the shin. In the patient history, the examining physician noted that the patient had a closed reduction of a hip fracture and had spent a week in the hospital before being discharged 1 week earlier.
The patient's initial vital signs were a temperature of 98.3° F and blood pressure of 140/80 mm Hg. Most important, her respiratory rate was 20 breaths per minute, and her pulse was 88 beats per minute.
Her respiratory rate was the clue the physician overlooked, Dr. Sullivan cautioned, together with the fact that her history said she had had hip surgery recently—and thus had spent time immobilized. In addition, the patient arrived in a wheelchair.
Instead, the physician focused on her complaint about her leg. He assumed he saw signs of cellulitis, and treated that with no further work-up.
The patient went home, only to develop respiratory distress 12 hours later. She was brought back to the ED and died of a massive pulmonary embolism.
The second case Dr. Sullivan outlined was like the first, in that the history should have given the clinician pause.
The patient in the second case was a 55-year-old obese woman who came to the emergency department complaining of nausea, vomiting, and diarrhea that had continued for 4 days.
When the patient arrived at the ED, both the triage nurse and the examining physician noted that they saw no specific signs of illness—the patient's color was good, and she had no upper airway congestion, chest pain, sweating, or cyanosis. Her abdominal exam was normal, her laboratory tests were normal, and a chest x-ray showed nothing.
However, the physician did note that the patient was in moderate distress. The patient's respiratory rate, noted by the triage nurse, was 34 breaths per minute. But the nurse recorded that as a normal rate, and nobody questioned it. Moreover, the patient's pulse was 96 beats per minute, and her temperature was not very high, at 100° F.
The medical history taken in the emergency department did not include the fact that the patient had had a prior PE. That was a fatal error, Dr. Sullivan continued, because the medical history did say that she was obese and had a clinical picture that did not really fit an infection.
When the woman became short of breath before leaving the emergency department, no one informed the physician. She collapsed and died as she was leaving the hospital.
In both of the cases, the patients' breathing and/or vital signs offered warnings that should have prevented premature diagnosis, Dr. Sullivan said.
One particularly tricky situation occurs when the patient might have pneumonia or some other infection, he cautioned. In cases that turn out to involve pulmonary embolism, patients often have a pulse that is too high and a temperature that is only mildly elevated. That combination should always raise a red flag for possible PE, Dr. Sullivan said.