Wednesday, October 27, 2010

Fastest Way To Wake Up A Patient

One thing that anesthesiology residency doesn't teach you is how to quickly and efficiently wake up a patient from general anesthesia. Sure, we all get grilled on the SAFEST method for emergence and extubation. However, in the real world, safe emergence is a given. Therefore to a surgeon what differentiates one anesthesiologist from another is how quickly the patient is transferred to recovery after a case is over. If the patient is still asleep after the surgeon has written the postop orders and finished talking to the patient's family, then you, my friend, are a slow anesthesiologist.

I've noticed this lack of exactitude results in two different philosophies (and possibly three which I will get to later) on how best to quickly wake up a patient. When I come in to the OR in the morning, I do my anesthesia machine check and I can easily see what the anesthesiologist who last used it was thinking about how to awaken the patient.  The machine usually has the last ventilatory setting of the previous patient still in place. From this, I can deduce two methods that are generally followed by anesthesiologists at the end of a case.

One is the slow and go idea for emergence. The vent settings on the machine will show a respiratory rate of about five with tidal volumes below five hundred. I presume the anesthesiologist is attempting to revive the patient's spontaneous respiration by allowing the patient's pCO2 levels to rise quickly. Once the patient is breathing on his own then the endotracheal tube can be removed.

The other method is the fast and furious approach. The vent setting will have the respiratory rate set in the high teens with large tidal volumes. The anesthesiologist was apparently trying to wake up the patient by swiftly blowing off the inhalational agents accumulated in the blood stream and lungs.  Once the patient is conscious, then the ETT can be safely taken out.

I don't think there has been a study on which process for emergence is better. There are just too many variables and either one works satisfactorily.  During residency I had attendings who advocated one or the other technique and the patients did just fine either way. Again the goal of residency training is safety first. But now in the real job market there is no real consensus on the best and fastest plan for emergence. So some unfortunate anesthesiologists get labeled as "slow."

So finally let me tell you about one colleague's practice for achieving fast emergence. I don't advocate his methods but it sure gets the job done. During surgery he gives absolutely no narcotics. He doesn't believe in preemptive analgesia. He thinks any narcotics given during the case will slow down emergence, which is true. His patients wake up in blinding pain from surgery whereupon he gives liberal doses of pain meds. Unfortunately the narcs rarely work rapidly enough before the patient is transferred to recovery. You can imagine the anesthesiologist is not one of the recovery room nurses' favorites when they are confronted with a miserable postop patient. But he gets the room turned over quickly and is thus well liked by the surgeons. Try it if you dare.


  1. I have an attending who, being a neuroanesthesiologist, does not believe in large doses of pain meds for any and all cases. A 6 hour spine case? "100 mcg of fentanyl and that should do ya"... or something like that. Obviously the patients wake up and move all extremities, but the screaming and guilt I feel are terrible.

  2. All debate is extinguished when one uses the "My Rule"... eg) How would I do this if this were MY ANESTHETIC, my daughter's, my son's, my mom's, my dad's... Anything else is negligent anesthetic care.

  3. Can someone clue me in? I had a 3 hr 1-level lumbar fusion today. It took me 30 mins to wake the pt up. Needless to say, I felt humiliated and felt like I did not know how to deliver anesthesia. The problem is that I can't understand why this happened.

    He was a healthy 47 y/o male who had been taking percocets at home for pain for the past 3 months. He had 100 mcg fentanyl for induction. Maintenance was low-dose TIVA/half-MAC combination (propofol 75 mcg/kg/min, remi .25 mcg/kg/min, and des 3%. No muscle relaxants . Dilaudid 1mg was titrated in the first hour of the case. Both remi and prop were discontinued 30 mins before end of case.

    As I began to plan emergence, I hypoventilated the patient to build up CO2. The pt took 30 mins to breathe and wake up. I was at such a loss. There was no Des, the prop and remi were gone, the only remaining drug was dilaudid. But 1 mg, really? Had I not given as much drug, I KNOW the pt would have bolted upright off the OR table from the prone position. I just don't get it. I can't explain the siuation. Either they move at critical portions in the case from pain, or they take forever to wake up. I can't seem to get it right? Does anyone have an explanation. It ruined my day and I felt like the biggest dumb ass.

    1. My money is on the propofol, as the one thing you could have changed because it tends to sit there in fluffy patients....turning it off sooner and maybe going up on the gas to 0.7 MAC? Or relying mostly on the remi which comes off in less than 10 mins