Paradoxically, medical instrumentation poses the greatest challenges in critical care units (CCUs) but generates the most litigation in areas such as obstetrics and anesthesia. CCUs are the subject of legal debate far in excess of the medical malpractice cases they spawn. Most of the legal attention has been focused on the right of patients to refuse life support rather than on medical malpractice issues. As financial considerations reduce the availability of CCU care, it is expected that the legal controversies will shift from refusal of care to denial of care and conventional malpractice claims. Before discussing the expected increase in CCU- related litigation, it is important to understand why a relatively simple problem such as obstetric monitoring has generated much more litigation than the difficult problem of CCU monitoring.

When physicians think of medical device litigation, it usually brings to mind products liability claims against the device’s manufacturer. Such primary litigation is a problem for device manufacturers but not a direct threat to physicians using the devices. The problem for physicians is secondary litigation. Secondary litigation arises from medical devices that perform properly but increase litigation against the physicians who use them. Safety devices such as monitors have generated most secondary litigation, although it can occur with life-supporting devices as well. The best-documented example of secondary litigation is that due to obstetric fetal monitors. The problems that arose from fetal monitors have implications for selection of new technologies by physicians and hospitals.

Electronic fetal heart monitors and pulse oximeters illustrate a continuum from devices that increase secondary litigation to those that decrease it. The widespread use of fetal heart monitors was accompanied by a dramatic increase in obstetric malpractice litigation. It is certain that factors other than fetal heart monitors were primarily responsible for this increase. It is also certain, however, that the use of these monitors did not decrease litigation and, in the cases where fetal heart monitor records are available, these records increase the probability of litigation when an infant is born damaged. Conversely, the widespread adoption of pulse oximetry in the operating room was accompanied by a dramatic reduction in malpractice claims against anesthesiologists. These monitors appear to be among the primary causes of this reduction in claims. They clearly are not being used against anesthesiologists in the way that fetal heart monitors have been used against obstetricians.

Secondary litigation does not imply a defectively designed product, at least not in the traditional sense. Fetal heart monitors perform accurately and reliably within the constraints of what they measure. Devices that are unreliable or otherwise directly dangerous to patients will be the target of primary litigation against the device manufacturer. Pure secondary liability is an issue for otherwise safe and well- engineered devices. Secondary liability becomes a problem when the device in question documents previously undocumented behavior indicating negligence on the part of the medical care providers, records data with ambiguous interpretations, and/or inappropriately leads to changes in medical care supervision, staffing, or patient contact because of reliance on the device.