Medical Malpractice in the Diagnosis and Treatment of Pulmonary Embolism

By Attorney J. Whitfield Larrabee

The Need for Prompt Diagnosis

The failure of doctors to properly diagnose and treat pulmonary embolism is a leading cause of unnecessary death in the United States.1 Scientists estimate that as many as 60,000 Americans die annually as a result of the failure to properly diagnose pulmonary embolism. More Americans presently die of pulmonary embolism than die of breast cancer. Because it is a common and lethal condition, the established ‘standard of medical care’ requires doctors to rule out a pulmonary embolism whenever a patient has symptoms and risk factors that raise a reasonable suspicion that the patient may be suffering from this condition. Untreated pulmonary embolism often leads quickly to death. When a patient has symptoms that raise a high level of suspicion for pulmonary embolism, doctors must respond to the situation as a medical emergency. A ‘wait and see’ approach subjects the patient to unacceptable risk.

Doctors must respond to the suspicion of pulmonary embolism as a medical emergency.

Where doctors are unsure if a patient suffers from deep vein thrombosis (DVT), the underlying cause of pulmonary embolism, they usually need to perform a ventilation/perfusion scan (V/Q scan), CT angiogram or a pulmonary angiogram to definitively diagnose the condition.2 When pulmonary embolism is not properly diagnosed, the mortality rate rises dramatically, largely as a result of recurrent emboli. Nearly a third of patients suffering from pulmonary embolism will die without treatment. Many patients die less than an hour after the onset of symptoms. All too often, doctors fail to perform essential tests and miss this diagnosis.

Doctors too often fail to perform essential tests and miss the diagnosis of pulmonary embolism.

Claims based on failure to properly diagnose pulmonary embolism fall within well established principles of medical malpractice law.3 Many cases are based on the doctor’s negligent failure to order appropriate diagnostic tests, negligent failure to follow proper diagnostic protocols, and negligent failure to recognize the possibility of pulmonary embolism based on the patient’s symptoms and risk factors. Where a physician should have a reasonable suspicion of pulmonary embolism, the standard of medical care requires that the physician promptly order appropriate diagnostic tests.4

A variety of risk factors and symptoms should give rise to a suspicion of pulmonary embolism. Risk factors include recent surgery, a history of venous thrombo-embolism (DVT), prolonged imobilization, congestive heart failure, cancer, fracture of the pelvis, femur or tibia, obesity, pregnancy or recent delivery, estrogen therapy (including the use of birth control pills), and inflammatory bowel disease.5 Over 95% of patients suffering from massive pulmonary embolism show signs of rapid breathing (tachypnea). Where massive pulmonary embolism leads to death, shortness of breath (dyspnea) is present in 60% of all cases . The failure of a physician to rule out pulmonary embolism when confronted with breathing abnormalities such as tachypnea and dyspnea in combination with other risk factors and symptoms may well amount to malpractice. Many patients have an elevated heart rate (tachycardia) or experience a loss of consciousness (syncope). 6 In cases where physicians confuse syncope with a seizure, they will likely fail to diagnose pulmonary embolism . Patients often experience chest or back pain, have abnormal breathing sounds (rales), have abnormal EKGs, or are sweaty (diaphoretic) . 7

The Importance of Proper Treatment

When pulmonary embolism is properly diagnosed, physicians have several treatment options which include: anti-coagulant drugs, clot busting drugs and surgical embolectomy. Prompt treatment with anti-coagulant (blood thinning) drugs such as heparin can reduce the mortality rate of the condition by about 90%.8 Because existing forms of treatment are so effective, the vast majority of preventable deaths from pulmonary embolism are the result of diagnostic failures. Once pulmonary embolism or DVT is diagnosed, patients are most often treated with high doses of heparin, which acts immediately to prevent creation of new blood clots and emboli. Most physicians would agree that the medical standard of care usually requires that a physician start full-dose heparin if he or she has a strong suspicion of pulmonary embolism, even before the V/Q scan can be obtained. This is because the risks of harming the patient from heparin treatment are far outweighed by the life threatening risk associated with pulmonary embolism. When the patient’s condition is stabilized with heparin, patients can normally be given the oral anticoagulant drug warfarin (Coumadin), a less powerful blood thinner, within two to five days. Treatment with warfarin will normally continue for weeks or months. To ensure that the blood is adequately thinned so as to prevent further thrombosis, physicians must perform blood tests to monitor the patient’s ‘activated partial thromboplastin time’ (aPTT). If physicians fail to properly monitor the patient’s aPTT and adjust the medication accordingly, the patient will sometimes die or suffer injury from recurrent pulmonary embolism or DVT.

Prompt treatment can reduce the mortality of pulmonary embolism by 90 percent.

In cases involving massive pulmonary embolism, more aggressive treatment with ‘clot busting’ drugs or surgery may be required. ‘Clot busting’ drugs are known as ‘fibrinolytic enzymes’ and include streptokinase, urokinase, and tPA. While they accelerate the rate at which clots dissolve, they also increase the risk of stroke significantly. Because massive pulmonary embolism is an emergent life threatening condition, physicians who fail to give fibrinolytic therapy immediately when a patient with pulmonary embolism shows signs of impaired circulation or ‘hemodynamic instability’ may be committing medical malpractice. In some cases, surgical removal of an embolism, known as an embolectomy, may be the appropriate course of treatment. Some patients suffering from massive pulmonary embolism cannot safely be treated with clot busting thrombolytic drugs. These drugs may not be suitable for patients who have suffered from stroke, recent surgery or cancer. In contrast to the recent past, advances in surgical technique make it possible for skilled surgeons to perform embolectomies with relatively low risk and high survival rates.9

Working Toward Solutions

Preventing future tragedies from occurring can be achieved through education, action in the medical community, and litigation. Substantially reducing the number of preventable deaths caused by pulmonary embolism is a goal championed by many heroes in the medical community. Although this goal is attainable, progress in reducing the number of preventable deaths has been elusive. Standards of care from doctor to doctor and hospital to hospital vary greatly. Improvements in primary medical education and continuing medical education are of course essential. Hospital wide initiatives to improve clinical practice through the use of diagnostic protocols can significantly reduce the number of needless deaths. Litigation can serve a variety of functions that lead to solutions. First, it can uncover problems which otherwise might be covered up or ignored. It can punish providers of poor care for their negligence, serve as a deterrent to careless behavior and can provide incentives for improvement. Finally, part of the solution must include providing a measure of justice to victims of bad medical practices and their families.

FOOTNOTES:

1. Fedullo, P.F., Tapson, V. F., The Evaluation of Suspected Pulmonary Embolism, New England Journal of Medicine, Vol. 349, pp 1247-56 (2003).

2. The PIOPED Investigators, Value of the ventilation/perfusion scan in acute pulmonary embolism: results of the Prospective Investigation of Pulmonary Embolism Diagnosis (PIOPED). Journal of the American Medical Association (JAMA), Vol. 263, pp. 2753-59 (1990).

3. Dinozzi v. Lovejoy, 20 Mass. App. Ct. 973 (1985); Kopycinski v. Aserkoff, 410 Mass. 410 (1991); Nickerson v. Lee, 42 Mass. App. Ct. 106 (1997).

4. Mcgrath v. Carson, ___ S.W.3d ___ (2002).

5. Fedullo, P.F., Tapson, V. F., The Evaluation of Suspected Pulmonary Embolism, New England Journal of Medicine, supra at 1248.

6. Feied, C.F., Pulmonary embolism. In: Rosen and Barkin, eds, Emergency Medicine Principles and Practice, 4th ed. 1998; 3: Chapter 111.

7. Feied, C.F., Pulmonary embolism. In: Rosen and Barkin, eds, Emergency Medicine Principles and Practice, 4th ed. 1998; 3: Chapter 111.

8. Carson, JL, et al., The Clinical Clinical Course of Pulmonary Embolism, New England Journal of Medicine, Vol 326, pp. 1240-1245 (1992); Goldhaber SZ, Morpurgo M. Diagnosis, Treatment, and Prevention of Pulmonary Embolism. Report of the WHO/International Society and Federation of Cardiology Task Force. Journal of the American Medical Association (JAMA) 1992;268:1727-1733.

9. Aklog, L., et al., Acute Pulmonary Embolectomy: A Contemporary Approach, Circulation, Vol. 105, p. 1416 (2002).