Risk Management

Post-Retrobulbar Retinal Artery Occlusion and Informed Consent for Clinical Investigation of Intraocular Lenses

Digest, Winter 1996

Allegation

Failure to obtain informed consent. Negligent administration of retrobulbar anesthesia, resulting in an incomplete central retinal artery occlusion.

Disposition

Jury verdict for the defendant ophthalmologist.

Case Summary

The patient was a 71-year-old woman who saw the insured with complaints of decreased vision and difficulty night driving. The patient denied any history of heart disease or diabetes. Uncorrected VA was 20/400 OD pinholing to 20/50 and 20/200 OS pinholing to 20/40. The insured diagnosed cataracts OU and discussed the risks, complications, and expectations of surgery. The patient was given a clinical investigation consent form to sign for implantation of a CILCO Intraocular Lens from Alcon Surgical, Inc. The consent form explained that the clinical investigation was under a Congressional mandate to study the safety and efficacy of intraocular lenses.

The patient underwent an ECCE with posterior IOL. No complications were reported during surgery. On the first post-op day, the patient reported she had slept well with no pain but could barely see out of her right eye. On examination, there was a trace of corneal edema superiorly. The central portion of her cornea was clear with 2+ cells and flare in the AC. The implant was well positioned, and the pupil reacted to light but not actively. A fundus exam revealed macular edema but only minimally. The patient was immediately referred to a retinal surgeon, who performed a fluorescein which showed poor but definite arteriole perfusion OD relative to OS. No emboli were seen, and there was no evidence of vasculitis. This was all consistent with an incomplete central retinal artery occlusion.

The patient was started on Coumadin. An ECHO showed a dilated left ventricle with a mild reduction in systolic contractility but no intracavitary thrombus. A bilateral carotid sonogram showed no narrowing. A 24-hour circadian monitor showed unifocal premature ventricular contractions but no apparent cardiac dysrhythmia as a source for arterial emboli. No evidence of arteriosclerotic retinal artery occlusion or emboli was found. The patient’s vision stabilized at count fingers OD and 20/60 OS with pinhole to 20/40.

Analysis

The ophthalmology experts who reviewed this case indicated that retinal artery occlusion is an unfortunate but known complication of a retrobulbar injection and that it can and does occur in the absence of negligence. Each of the experts reviewed the recorded technique used for the injection and was firmly able to defend the insured’s actions as well within the standard of care. The plaintiff’s attorney, on the other hand, was able to find an expert who stated that this result should not have happened in skilled hands. This expert also opined, without any degree of specificity, that this degree of vision loss would not have occurred if the insured had provided more prompt and appropriate follow-up care.

All of these issues were adequately dispelled by the defense experts, but there was one remaining issue that undermined the defendant’s case: the patient claimed she had not been informed that the lens being used in the surgery was under investigation, and had she known this, she never would have undergone the surgery. She also claimed the insured never mentioned this type of vision loss as a complication and had assured her that this was a “simple procedure” and “not to worry about it.” Unfortunately, the insured had documented nothing in his office records regarding his informed consent discussion with the patient. Additionally, the required consent form that the patient signed before surgery under the protocol of the investigational study was nowhere to be found in the medical record. The lens manufacturer claimed it had never received a copy of the consent form and thus sidestepped involvement. Without this documentation, it was questionable whether the case could be defended. Serious thought was being given to settling the case when the lens manufacturer finally secured a copy of the required consent form, signed by the patient and filed with the state Investigational Research Board. The case was defensible again.

At trial, defense counsel was able to successfully argue the informed consent issues, which allowed the jury to focus on the remaining medical issues. A defense verdict was granted by the jury after a brief two-hour deliberation.

Risk Management Principles and Commentary

This case illustrates the difference in the legal effect between generic informed consent and a protocol-required informed consent for research purposes. Lack of documentation of the basic informed consent process often can be overcome at trial if the surgeon testifies as to his or her usual and customary discussions with patients about complications and alternatives prior to surgery. It becomes a credibility issue but may not be a fatal flaw in every circumstance.

However, failure to document consent when required by a research or investigational protocol is a fatal flaw that can totally undermine an otherwise defensible case. The “testimony of customary practice” defense does not apply in such cases. If it can be shown that a patient participating in a research project did not sign a research consent form, the investigator surgeon will be in violation of the research protocol itself and any testimony he or she may offer will not correct the violation. Under research conditions, if any specification of the protocol is breached, particularly in the areas of medical qualifications or exclusions for a particular research patient, the defense of the underlying case will be seriously jeopardized. Physicians who participate in a clinical investigation of any size or description must be particularly careful with documentation throughout the process because less leniency will be afforded by the legal system.