Letters to the Editor
Spinal Lidocaine Toxicity Debate Continues
To the Editor:
I read with interest Dr. deJong's article concerning spinal Lidocaine.
In 25 years of practice, I've had one patient who had a partial cauda equina syndrome in which 2% Lidocaine was injected (total 2cc at most) during a wet tap with an attempted epidural. The residual is a partially emptying bladder and some numbness in the perineal area, but the patient has full sexual function (male).
As I read Dr. deJong's concerns about the effect of Lidocaine molecules on the spinal cord and nerve roots, I found myself continuing to ask, "Why don't we see this more often with epidural anesthesia? Surely the molecules of lidocaine that diffuse through the aura and coverings of the dorsal nerve roots do not undergo a detoxification process while transiting from the epidural space to the subarachnoid structures?"
Do you or anyone have an answer to this question? Surely we achieve a CSF concentration of Lidocaine using epidurals that must approximate that achieved with 2% subarachnoid Lidocaine? Have I missed something here, o should we all be considering abandoning Lidocaine for epidurals as well?
I would welcome responses from Dr. deJong and other Newsletter readers.
Clair S. Weenig, M.D.
Assistant Clinical Professor
Department of Anesthesia
University of California Medical Center, San Francisco, CA
An Historical Eulogy For Spinal Lidocaine?
To the Editor:
Dr. deJong in the Fall APSF Newsletter has delivered the death knell to the use of lidocaine spinal anesthesia. As this final nail is driven into the coffin, may I be permitted a few words in eulogy.
In 1952, I established the Department of Anesthesiology at the then Providence Lying-In Hospital (PLI) in Providence, Rhode Island. This department was to become the first to provide coverage of obstetrics in a maternity hospital, 24 hours a day every single day of the year. This was an era when general anesthesia for delivery was de rigueur and spinal anesthesia was the bete noire, despite the fact that there was an appreciable maternal morbidity and even mortality associated with general anesthesia.1,2 The gospel at this hospital was according to that obstetric icon of the day, Greenhill. He declared that "Obstetric spinal anesthesia is the most dangerous type of anesthesia for pregnant women."3 this sentiment was further echoed by a letter to the editor of the Journal of the AMA from the director of an anesthesia department who questioned why "spinal anesthesia with its headaches and neurological complications in such a large percentage of cases should be used in obstetrics."4
The demographics were such that the Providence Lying-In Hospital was the ideal crucible wherein to test the validity of these beliefs. Providence was in effect a city state with extended family groups, closely bonded by ethnicity and religious beliefs. Large families were in vogue and the per capita birthrate was about the highest in the country. The majority of the deliveries in the state took place at the PLI hospital. The average postpartum hospital stay was 5 days, which provided us with the opportunity to get a handle on any immediate or early neurological deficits. Every parturient was visited daily during this hospital stay by a trained observer. She was asked such leading questions as "do you have numbness, weakness, or pain in your back or legs?" The population of Rhode Island was relatively immobile and most patients were seen at 6-8 weeks for the first postpartum visit. At this time the same leading questions were asked by the obstetrician. In addition, from 1952-1956, contact was made with the patients some three times a year by mail or by phone regarding any complications that might have ensued. Probably of greatest importance was the fact that Rhode Island was the spawning ground for a new breed tort attorneys, specializing in medical negligence. Needless to say that they followed our study with more than casual interest and served as watchdogs par excellence. Our study1 together with our joint enterprise with Otto Phillips5 was and probably remains the largest extant series of deliveries utilizing 5% lidocaine for spinal anesthesia in obstetrics.
These studies are significant for the absence of sequelae that could be attributed to lidocaine-exposures neurotoxicity. To add to the objectivity in the Phillips series, all postpartum suspected neurologic deficits were evaluated by neurologists. In the period 1952-1972 with just under 80,000 deliveries at PLI with 5% lidocaine, there was not a major neurological complication attributed to this agent. The "dysthesiae" encountered were transient in nature. We are here however t bury lidocaine for spinal anesthesia--not to praise it. There must, however, be a fond hail and farewell for an agent that has stood so many women in good stead.
The discrepancy between the above mentioned results and the present-day concern with the TRI syndrome invites much study and explanation.
Herbert Ebner, M.D.
Grand Cayman, Cayman Islands, BWI