Chest
Volume 71, Issue 5, May 1977, Pages 587-591
Journal home page for Chest

Clinical Investigations
Methemoglobinemia Induced by a Topical Anesthetic Spray (Cetacaine)

https://doi.org/10.1378/chest.71.5.587Get rights and content

In two seriously ill patients, cyanosis developed shortly after a topical anesthetic spray (Cetacaine) was used. In both cases the presence of methemoglobinemia was suggested by a discrepancy between the arterial oxygen tension and the oxygen saturation of hemoglobin, as measured spectrophotometrically. The characteristic responses of the spectrophotometric oximeter to blood containing different concentrations of methemoglobin are described. Physicians administering this topical anesthetic spray (Cetacaine) should be aware of the possible development of methemoglobinemia.

Section snippets

Case 1

A 77-year-old man underwent repair of a traumatic hernia of the left hemidiaphragm on Oct 9, 1972. Anesthetic agents and other drugs received during the operation included thiopental, fentanyl, droperidol, d-tubocurarine, and succinylcholine. On Oct 11, atelectasis of the lower lobe of the left lung developed. Bronchoscopic examination was performed with the “liberal” preparation of the pharynx by use of a topical anesthetic spray (Cetacaine). At the conclusion of the procedure, the patient was

Methods

Concentrations of methemoglobin were measured spectrophotometrically.1, 2 Unfortunately, in our present cases, the measurements were made several hours after the specimens of blood were drawn, and the actual concentrations of methemoglobin may have been higher than those reported.

The topical anesthetic spray (Cetacaine) was added to blood from our first patient on the day after administration of methylene blue, as well as to the blood from an otherwise normal patient. Neither sample developed

Discussion

Benzocaine can cause methemoglobinemia when applied to infants as an ointment,4, 5, 6 a rectal suppository,7 and a powder vaporized into the mouth.8 In adults, 0.15 to 0.3 gm of benzocaine administered orally has caused cyanosis.9

This particular topical anesthetic spray (Cetacaine) contains 14 percent benzocaine, 2 percent butyl aminobenzoate, and 2 percent tetracaine hydrochloride, as well as benzalkonium chloride and cetyldimethyl ethyl ammonium bromide, with Freon as the propellant. To our

Acknowledgments

Mr. Lester J. Clapp and Miss Yvonne M. Seipel performed the tonometric, blood gas, and oximetric studies.

References (10)

There are more references available in the full text version of this article.

Cited by (72)

  • Synthesis and methemoglobinemia-inducing properties of benzocaine isosteres designed as humane rodenticides

    2014, Bioorganic and Medicinal Chemistry
    Citation Excerpt :

    In 1901 benzocaine (Fig. 1) was found to possess anaesthetic properties,2 and was subsequently introduced to the market under the trade name Anesthesin®.3 Still widely used today in the clinic as a topical anaesthetic,4 benzocaine has been observed to induce methemoglobinemia in some patients,5–7 that is an impairment of the red blood cells capacity to transport oxygen, in some instances leading to potentially dangerous levels.8–10 While such a side effect naturally poses a concern to medicine, benzocaine-induced methemoglobinemia, and its potential application to pest management, could be considered for further exploration.

  • Dark chocolate arterial blood gas after bronchoscopy

    2013, American Journal of the Medical Sciences
    Citation Excerpt :

    Topical anesthetic agents as benzocaine spray and lidocaine cause an increase in the production of metHb by altering the iron state in heme from ferrous (Fe2+) to ferric (Fe3+) state, which is unable to bind oxygen. Methemoglobinemia during bronchoscopic procedures can be difficult to detect, but diagnosis is suggested by the occurrence of cyanosis that does not improve after the administration of oxygen and a marked decrease in oxygen saturation despite an above-normal partial pressure of oxygen in arterial blood.1 MetHb causes errors in pulse oximetry readings because it also absorbs red and infrared light at the wavelengths used.

  • Preparation of the Patient for Awake Intubation

    2013, Benumof and Hagberg's Airway Management
  • Preparation of the Patient for Awake Intubation

    2012, Benumof and Hagberg's Airway Management: Third Edition
  • Methemoglobinemia-an unusual cause of intraoperative hypoxia

    2007, Oral Surgery, Oral Medicine, Oral Pathology, Oral Radiology and Endodontology
    Citation Excerpt :

    The first reported case of bluish discoloration of the skin and mucous membranes was in 1890.15 Significant methemoglobinemia is seen in roughly 1 of 7,000 exposures to benzocaine.16 A recent review of the adverse events reported to the FDA suggested that there were more than 132 reported cases of benzocaine-induced methemoglobinemia in the 5-year period between 1997 and 2002, 2 of which were fatal events.17

View all citing articles on Scopus

Manuscript received August 11, 1975; revision accepted September 22.

View full text