Volume 10, No. 2 • Summer 1995

Safety of 5% Lidocaine Heavily Defended

Casey D. Blitt, M.D.

To the Editor

In 1993, a Swiss article (1) reported transient neurologic toxicity after hyperbaric spinal anesthesia with 5% lidocaine. This article was accompanied by an editorial (2) that essentially condemned the use of 5% lidocaine in 7.5% dextrose for spiral anesthesia. Subsequent correspondence in that Journal debated the issue of neurotoxicity from lidocaine focusing on ‘heavy’ versus ‘light’ and the development of cauda equina syndrome in conjunction with continuous spinal anesthesia with hyperbaric 5% lidocaine. (3)

The number of spinal anesthetics performed in the United States with 5% hyperbaric lidocaine annually is probably somewhere between 500,000 and 1,000,000. Many clinicians consider single-dose hyperbaric spinal lidocaine the anesthetic of choice for patients undergoing transurethral resection of the prostate or fixation of a fractured hip. In our risk management database, we have 3,372 administrations of single dose 5% hyperbaric lidocaine without known neurologic sequelae. If single dose hyperbaric lidocaine is indeed neurotoxic, we should be observing the results of this neurotoxicity across the United States. In terms of onset, duration of action and success rate, 5% hyperbaric lidocaine deposited in the subarachnoid space is ideal for a subgroup of patients having particular procedures, as previously mentioned. There is no comparable pharmacologic alternative for the practitioner. Although the Swiss study is interesting, it must be viewed as a clinical aberration with questionable implications for subarachnoid Lidocaine.

It is inappropriate to deprive the clinician in the United States of a valuable local anesthetic for subarachnoid anesthesia. More importantly, our patients should not be denied the use of heavy lidocaine for spinal anesthesia. We have communicated with many clinicians throughout the United States and all indicate that they continue to use single dose 5% hyperbaric lidocaine for spinal anesthesia, especially for patients undergoing TURP and hip fracture fixation. We will continue to do likewise as we consider single dose hyperbaric lidocaine to be the best local anesthetic for spinal anesthesia in our patients. We are optimistic that experienced investigators will prospectively evaluate the issue of neurotoxicity secondary to single dose 5% hyperbaric lidocaine and settle the issue. Throughout the years, our specialty has been plagued with the phenomena of “finger pointing’ at the wrong variable (such as the suggestion that isoflurane causes cancer).

In the United States, single dose 5% hyperbaric lidocaine for spinal anesthesia has stood the test of time. It should and will continue to be used by clinicians when indicated.

Casey D. Blitt, M.D.

Old Pueblo Anesthesia Tucson, AZ


  1. Schneider M, Ettlin T, Kaufmann M. et al. Transient Neurologic Toxicity after Hyperbaric Subarachnoid Anesthesia with 5% Lidocaine. Anes and Analg 1993; 76:1154-7.
  2. deJong, RH. Last Round for a ‘Heavyweight? Anes and Analg 1994; 78:3-4.
  3. Thompson, GE. This Fight Isn’t Fair. Anesth and Analg 1994; 79:604-605.