Succinylcholine Use and Dantrolene Availability: Reply

Abstract

W e read with interest the study by Larach et al., 1 which performed extensive and complex analyses of three databases (i.e., Multicenter Perioperative Outcomes Group, the North American Malignant Hyperthermia Registry, and the Anesthesia Closed Claims Project) as well as performed a systematic review of literature. One of the conclusions of the study was that succinylcholine alone without volatile anesthetics may trigger malignant hyperthermia (MH). The authors seem to allude that this finding negates the Society for Ambulatory Anesthesia recommendation 2 that permits Class B ambulatory facilities to stock succinylcholine for rescue of laryngospasm without stocking dantrolene. However, the Larach et al. study 1 has significant limitations, particularly the fact that the analyses did not include data from Class B facilities or the use of succinylcholine for laryngospasm. The succinylcholine dose used for situations assessed in this study (i.e., possible difficult airway or electroconvulsive therapy) is generally much higher, and extrapolating the conclusions to low-dose (20 to 30 mg) succinylcholine commonly used to treat laryngospasm may be inappropriate. Of note, there are no reports of MH with low-dose succinylcholine. Also, as stated in the accompanying editorial by Hopkins, 3 "the evidence presented in this article is insufficient to convince me that succinylcholine in the absence of volatile anesthetics can trigger a life-threatening progressive hypermetabolic response in MH-susceptible patients..."Class B facilities provide for minimally or moderately invasive procedures not requiring general and/or regional anesthesia. These facilities, which are growing in number, typically do not stock dantrolene because they do not use (or have the ability to use) volatile anesthetics. To avoid the costs associated with carrying and replacing dantrolene, they often elect not to stock succinylcholine, as its presence is perceived to mandate the availability of dantrolene. Given that the use of succinylcholine for laryngospasm is under reported, although there is a high likelihood of overdiagnosis of MH, the prevalence of MH is credibly significantly lower than the incidence of laryngospasm, which makes this a significant patient safety issue. The Society for Ambulatory Anesthesia position

Variation in propofol induction doses administered to surgical patients over age 65

“…This was a retrospective observational study conducted under an approved IRB protocol in collaboration with the MPOG. 22,23 MPOG is a consortium of over 50 hospitals that maintain a data set of electronic health record (EHR) and administrative data from contributing sites across 21 states and two countries. The MPOG data collection methods have been previously described (see www.mpog.org).…”

The Knowledge Profile, Competence and Pending Problems of Chinese Anesthesiologists in Dealing with Malignant Hyperthermia: A Cross-Sectional Survey

“… 3 , 20–23 Undoubtedly, inadequate intraoperative monitoring methods would impede early detection of MH, furthermore, lack of supplies of dantrolene would delay the appropriate treatment. 24 We consider that each hospital manager and chief anesthesiologist have the responsibility to store dantrolene for locations where MH trigger drugs are regularly used, the recommended stock level should be 24–36 vials of dantrolene, and if further dantrolene cannot be obtained within 30 min, an increased stock level should be 48 vials. 7 …”

Age-Specific Clinical Features of Pediatric Malignant Hyperthermia: A Review of 187 Cases Over 60 Years in Japan

“…Regarding the incidence of mortality from acute MH in pediatric patients, Nelson and Litman 6 reported a mortality rate of 4.5%, compared to the overall mortality rate as high as 8.8% since 2000 in the present study. Dantrolene has been linked to the development of MH complications if administered late 20 and to increased mortality if not administered. 5 We speculated that the reduction in mortality was related to the use of dantrolene and the anesthetics used, but there was no significant difference in the use of dantrolene before or after 2000, nor was there a difference in mortality due to the inhaled anesthetics used.…”

“…CGS for MH is a scoring system that aims to make a clinical diagnosis from the symptoms of MH and calculates the score (range from 0 to 108 points) by adding the points of the clinical processes rigidity, muscle breakdown, respiratory acidosis, temperature increase, cardiac involvement, and others. In addition, the patient's symptoms are divided into 6 ranks according to the score: 0 point indicating MH likelihood to "almost never," range from 3 to 9 points indicates MH likelihood of "unlikely," from 10 to 19 points indicated MH likelihood of "somewhat less likely," from 20 A flowchart of the patient selection process is shown in Figure 1.…”