Circulation 36,825 • Volume 17, No. 3 • Fall 2002

Creation of Observational Unit May Decrease Sleep Apnea Risk

Jonathan L. Benumof, MD

To the Editor

Dr. Lofsky has done the anesthesia community a significant and positive service by writing about the difficulties associated with the anesthetic management of 8 patients with obstructive sleep apnea (OSA) that arose from the Doctors Insurance Company medical malpractice experience (APSF Newsletter 2002;17:24-5) (as she had previously done in describing 12 cases of vision loss following spine surgery [APSF Newsletter 1998;13:16-7]). On the basis of having done an in-depth review of approximately 10-12 medical malpractice cases involving patients with severe OSA (usually obese) with disastrous respiratory outcomes, I also felt inspired to publically discuss the problem.1-4 Although I agree with just about all of Dr. Lofsky’s statements, I disagree with the statement that respiratory arrest following opioid administration to OSA patients “could have been prevented by audible pulse oximetry monitoring on the ward.” This erroneous comment is very important because if the statement is relied upon to ensure safety, then the practice could lead to more negative outcomes in the future.

The medical system in the United States of America at present, with respect to the intensity of postoperative care, is basically an all (ICU care) or next-to-nothing (patient alone in an isolated room on the ward) choice; there is no middle ground monitoring environment (including visual and electronic surveillance) for the morbidly obese patient with severe OSA, who is receiving narcotics and/or sedatives, who is not intubated, and does not have special lines (tracheal tube, arterial-line, pulmonary artery catheter, Foley catheter, and so forth). In many of the OSA medical malpractice cases I have reviewed, an attempt was made to create a middle ground monitoring environment by placing the patient in a room near the nursing station, keeping the door open, the lights on, trying to have a family member continually present, putting an audible pulse oximeter (SpO2) on the finger and maybe some sort of apnea alarm monitor on the patient. These middle ground monitoring solutions simply do not work; e.g., the family member goes to the cafeteria, no nurse (or any other care giver) passes by the room for many minutes (the door being open and the lights on and the room being near a nursing station then becomes irrelevant), and no one hears any change in the sound of the pulse oximeter and the patient dies.

Postoperative patients with OSA do not necessarily need an ICU, but they definitely need more monitoring care than normal patients. In my opinion, the solution that will work best is the creation of observational units with RN:patient ratios of 1:3-4 with frequent visual observation and noninvasive blood pressure, SpO2, and EKG monitoring at each bed site, as well as at a central bank of monitors at the nurse’s station. The recent development and clinical availability of a remote (by pager) SpO2 and heart rate monitoring notification system, such as the Nellcor “In Touch”™ monitoring system, is a very significant step in the right direction. In the absence of having an observational unit or a remote SpO2 and heart rate pager monitoring and notification system, and in the presence of concerns about the risk of respiratory arrest following narcotic administration to an OSA patient, my advice is to send the patient to the ICU. A simple audible SpO2 monitor in an isolated room on the ward will not work.

Jonathan L. Benumof, MD
San Diego, CA


  1. Benumof JL. Obesity, sleep apnea, the airway and anesthesia. 52nd Annual ASA Refresher Course Lecture. 2001:234:1-7.
  2. Benumof JL. Obstructive sleep apnea in the adult obese patient: implications for airway management. J Clin Anesth 2001;13:144-56.
  3. Benumof JL. Obesity, sleep apnea, the airway and anesthesia. The American Society of Anesthesiologists Refresher Courses in Anesthesiology. 2002;31 (In Press).
  4. Benumof JL. Obesity, sleep apea, the airway and anesthesia. 53rd Annual ASA Refresher Course Lecture. 2002: (In Press).