Under what circumstance would res ipsa loquitur be unlikely to apply in an anesthesia case?

• A. When there is a proven intervening cause or lack of exclusive control by defendant.
• B. When the patient signs consent.
• C. When there is no harm.
• D. When the case involves only billing errors.

Answer: (A)

Res ipsa loquitur works when a patient's injury is of a kind that normally wouldn’t occur without negligence, and the defendant controlled the instrumentality that caused the injury, with no other reasonable explanation. In anesthesia cases, this lets a patient prove negligence without direct proof of specific acts. But if there’s a proven intervening cause or the defendant did not have exclusive control of the instrumentality, that inference falls apart. An intervening cause introduces another explanation for the injury, and lack of exclusive control means the injury could have been caused by someone else or by factors outside the defendant’s sole responsibility, so the plaintiff cannot rely on res ipsa. That’s why this scenario makes res ipsa unlikely to apply.

The other options don’t address the conditions needed for res ipsa loquitur: consent is about agreeing to treatment, not proving negligence; no harm means there’s no injury to explain; and billing errors are about administrative issues, not the causation or control of an injury in the operating room.