Due to the difficulties in attributing the cause of a heart attack to the claimant’s work, a number of states, including Nebraska, require the employee or the employee’s dependents to establish compensability of the cardiac event using a heightened standard of proof [see Larson’s Workers’ Compensation Law, §§ 43.03, 44.04, 46.03]. Nebraska refers to this heightened standard as the “split test of causation,” consisting of two elements: (1) legal causation and (2) medical causation [see Leitz v. Roberts Dairy, 237 Neb. 235, 465 N.W.2d 601 (1991)]. Under this test, an exertion- or stress-caused heart injury to which the claimant’s preexisting heart disease or condition contributes is compensable only if the claimant shows that the exertion or stress encountered during employment is greater than that experienced during the ordinary nonemployment life of the employee or any other person.
In a recent decision, Wingfield v. Hill Bros. Transp., Inc., 288 Neb. 174, 2014 Neb. LEXIS 78 (May 16, 2014), the Supreme Court of Nebraska extended the split causation test to a claim involving an episode of deep vein thrombosis and pulmonary embolism, finding that the state’s Workers’ Compensation Court appropriately denied the claim of a truck driver who claimed a blood clot and subsequent embolism was caused by his employment.
The claimant, who had driven trucks for almost 35 years, but who had worked for only one month with the employer, normally worked 10 hours per day and was seated for most of that time. In February 2010, after one of his work days with the employer, the claimant felt ill, developed chest pains and saw a physician who hospitalized the claimant. The diagnosis was deep vein thrombosis and pulmonary embolism.
Although the claimant alleged that his condition was the result of the February 2010 incident, that episode was not his first diagnosis of those conditions. He had been hospitalized for the same conditions on two prior occasions before starting his employment with the employer.
The compensation court received evidence that prolonged sitting is a risk factor for the development of deep vein thrombosis, or a blood clot forming in the deep venous system. The compensation court dismissed the truck driver’s claim, however, observing that the claimant’s prior episodes of deep vein thrombosis and pulmonary embolism required it to consider the appropriate level of proof necessary to establish that his injuries arose out of his employment with the employer and that it was appropriate to apply the split test that requires proof of both legal and medical causation under Leitz.
After applying the split causation test, the compensation court concluded that the claimant had failed to prove medical causation–that the employment contributed in some material and substantial degree to cause the injury. In support of its conclusion, the court relied upon the opinion of a physician retained to review the medical records in the case. The physician concluded that the claimant was “not adequately anticoagulated” at the time of his admission to the hospital in February 2010. His anticoagulation medication was at a non-therapeutic level and was consistent with a person who was not taking any type of anticoagulation medication. Thus, the physician concluded that the “February 26 episode of pulmonary emboli was not specifically work related but rather a combination of multiple risk factors, most importantly, inadequate anticoagulation at the time of admission.”
Finding the physician’s opinion persuasive, the compensation court found that the claimant had failed to establish that his employment caused the February 2010 incident. The Supreme Court affirmed.
Noting that the “split test” (medical/legal causation) had already been extended to stroke cases, the high court held that it was also applicable to the instant case. The court allowed that under the legal test, the claimant must establish that the proximate cause of the heart attack was work related and thereby break any causal connection between the natural progression of a preexisting condition or disease and the injury at the workplace. Otherwise, the fact that the heart injury occurred at work would be strictly fortuitous. Quoting Larson, § 46.03, the court indicated that under the medical test, “the doctors must say whether the exertion (having been held legally sufficient to support compensation) in fact caused this collapse.” The medical test establishes whether the exertion contributed causally to the collapse as a matter of medical fact.
The Supreme Court ruled that because the compensation court’s findings were not clearly wrong, the dismissal of the claim had to be affirmed.