Causation: Get Medical Expert Witness Advice


Emergency physicians who offer expert witness services are primarily asked to opine about two issues: standard of care and causation. If the standard of care has been met, there is no case; but even if there has been a failure to perform within the standard of care, there has to be proximate cause between that failure and the damages. In many instances, however, it is much harder to show causation than it is to show that a significant error was made.


For instance, a 63-year-old male presents to an Emergency Department (ED) complaining of upper abdominal pain. A cardiac work-up is not done. The patient feels better after being treated with an antacid and is discharged home but is found dead in bed the next morning. It’s not a stretch to opine that an acute myocardial infarction (AMI) should have been high on the list of differential diagnoses and that a cardiac work-up should have been done in the ED. However, without aberrancies on an EKG to point to, an elevated troponin to note, or an autopsy report documenting evidence of early myocardial changes compatible with an AMI to reference, it becomes difficult to opine, more probably than not, that the man died of an AMI. Causation, then, becomes speculative.


The expert witness consultant who feels comfortable working with an attorney on a specific case must be willing to provide pro or con opinions regarding the standard of care issue and should feel comfortable opining about causation. However, it may not always be in the best interest of the retaining attorney to rely on that same expert to be the causation expert. There are many unusual or difficult to manage emergencies where the care regarding the causation question would not be administered by the emergency physician or would only be administered after consultation and collaboration with a specialist in some other field of medicine. In those instances, the emergency physician will not to be in the strongest position to support or refute causation, especially in those cases where even experts in the specialties that are expected to provide the advice on consultation and the ongoing care of the patient in the hospital may debate what the best course of action should have been. Under those circumstances, it may be best to assign the responsibility of “causation expert” to an expert in the specialty which is most familiar with the nuances of the treatment of the problem and the likelihood that, if employed, the treatment would have been efficacious.


To use a cardiac emergency again as an example, suppose that a patient presents to an ED, is diagnosed with an AMI, but needs to be transferred to another hospital to obtain percutaneous cardiac intervention (PCI). If an unacceptable delay in transfer occurs, it is easy for the emergency medicine expert to find that delay to be below the standard of care. But the damages “caused” by that delay are measured in lost myocardial function. Who is in the best position to opine with credibility regarding that causation issue, the emergency physician who does not do PCI or measure cardiac output functions or an expert in cardiology who performs both of those tasks?