Letter to the Editor:
To the Editor:
Those post hoc rumors of bronchospasm from bisulfite in generic propofol (APSF
Newsletter, Summer 1999) are questionable. Bronchospasm occurs quite apart
from general anesthesia. As a complication of general anesthesia it was familiar
before any of the drugs mentioned by Dr. Papincak became available. Usually
it is an incidental complication of general anesthesia, not a specific drug
reaction. The first case cited by Dr Papincak was a known asthmatic, so hers
may have been just another attack. The victim in an asthmatic attack is striving
to expectorate allergens, pollens, Charcot-Leyden crystals, Curschmann's spirals,
etc. Unable to manage full-blown coughs he has paroxysms of ineffective coughlets,
i.e. "bronchial fibrillation." His bronchial mural muscles are obstructed
by spastic bronchial sphincters. Anesthetic agents, cocaine, vapors of ether,
pentothal, etc. as foreign bodies in the airways have important irritant potentials,
and some airways are especially irritable. As physicians we know that conflict
between mated muscles is a major cause/mechanism of idiopathic diseases, including
Parkinson's disease, wryneck, and cramps: menstrual, crural, gastric, cardiac
etc.
A common cause of bronchospasm complicating general anesthesia is the endotracheal tube because when the patient is light, he tries to cough or fibrillate it out. This is probably what happened in Dr. Papincak's second case. The other common cause of laryngo/masseter/bronchospasm complicating induction is a mass of mucus (despite the patient's denial) present in the pharynges (postnasal drip etc.) before induction begins. When induction is rapid, exaggerated inspirations forcibly inhale that bolus. Depending on how and where it strikes, some more or less successful defensive reactions follow. These include one or more of the following: coughing, spasms as already mentioned, respiratory arrest, blood-holding (cardiac arrest), generalized spasms, i.e. "Laryngeal Epilepsy" which formerly was called "ether convulsions."
Were measures taken to inspect the pharynges and eliminate potentially dangerous missiles from the throat before induction? Those pre-induction precautions are not cited in the reports. Such superficial accounts perpetuate that "dark age scenario "wherein the surgeon blames the anesthesia and the sandman blamed the agent, without any factual analysis.
When things go wrong in the O.R., there are five groups of possible causes: 1) Pre-existing conditions in the patient, 2) factors related to the anesthesia, 3) factors arising from the operation, 4) bizarre and miscellaneous factors, and 5) some combination of above.
Being arbitrarily based on the assumption that "whatever follows the administration of a drug has to be due to that drug," your generic propofol debate is clinically irrelevant. Harold De Monaco, although not an anesthesiologist, made some good, though also clinically irrelevant, points.
M.G.Baggot, M.D.
Granite City, IL
To the Editor:
Although I am a retired anesthesiologist, I would like to comment on the
current propofol controversy, specifically the letter from Dr. Papincak. For
the record I have no vested interest in either side.
Dr. Papincak reports two cases. In reading the reports as published, I am concerned that Dr. Papincak was quick to attribute the complications encountered to the bisulfite. I am concerned that there is no mention of obtaining any history of allergies in the preoperative evaluations of the patients; and, second, there is no indication that there was any follow-up evaluation of the two patients. In this latter regard, was there any additional history obtained from the patients which might have indicated a sulfite problem and was there any attempt to have the patients further evaluated in this regard?
I am not discounting the potential cause of the complications encountered by Dr. Papincak; however, he would have served us all better if he had sought and provided more information.
In the forty-five years in which I practiced, there were several instances in which otherwise unexplained complications were initially and quickly attributed to a medication when, after further study, it was not the case.
I personally encountered a patient who presented similar problems to those described by Dr. Papincak, well before the advent of propofol. The interesting aspect to this case is that our anesthesia department covered two hospitals. This patient presented on three occasions with a different surgeon and a different anesthesiologist each time. It was only when the last instance came to a department M and M conference that we requested the patient's records from both hospitals and discovered that it was the same patient. After the first episode he was told to always inform the anesthesiologist that he had had this problem. It was further suggested that he consider regional anesthesia where applicable. He was resistant to the idea of regional anesthesia, although in all three instances the surgery was on his knee. Furthermore, he failed to tell anybody of his prior adverse anesthesia experience(s). Having failed to convince him of the seriousness of the problem or to be able to contact him, we resorted to sending him a certified letter, return receipt, detailing this potentially lethal problem.
Finally, I would emphasize the importance of doing a thorough evaluation of all patients where a complication such as those encountered here occurs. I have always taken pride in reading about a case of "Ether Allergy" occurring in the South Pacific during World War II and how, under conditions considered primitive by today's standards, this was documented.1
Donald W. Stein, M.D.
Oro Valley, AZ
Reference
1. Stein, Major Hermann B. "Ether Allergy: A Case Report". Anesthesiology
1945; 6:515-521. (My father!)
To the Editor:
Dr. Tinker's letter in the Spring 1999 issue of the APSF Newsletter pointed
out some of the differences between Diprivan (Zeneca) and propofol with sodium
metabisulfite (Baxter). I would like to suggest another potential hazard that
the introduction of this new formulation of propofol may present.
In the past several years, a number of articles have appeared in the literature regarding the advantages of propofol-thiopental mixtures. Although to my knowledge Zeneca has not endorsed this practice [correct, it has not - Ed.], many anesthesiologists have begun using this mixture. As Dr. Tinker has pointed out, propofol with sulfite is maintained at a significantly lower pH then Diprivan with EDTA. I am not aware of any studies examining the stability of this formulation in combination with thiopental (a drug with a very high pH). In hospitals with both formulations available, the potential exists for one to mix thiopental with the wrong formulation of propofol with unpredictable and potentially disastrous results. I hope that those departments where these mixtures are used will take this into consideration before adding propofol with sulfites to their formulary and wait for the appropriate studies to be performed.
Jonathan Hamburger, MD
Greater Baltimore Medical Center
Baltimore, MD