# The Effectiveness of a Mobile National Remote Emergency System for Malignant Hyperthermia in China: Retrospective Pre-Post Implementation Study

## TL;DR

A mobile system in China improved treatment and survival for patients with malignant hyperthermia, a rare but dangerous condition during surgery.

## Contribution

The study demonstrates how a WeChat-based remote emergency system can effectively reduce MH mortality and improve dantrolene administration in China.

## Key findings

- Mortality dropped from 55.9% to 7.1% after implementing the MH-NRES system.
- Dantrolene use increased significantly from 44.1% to 78.6% post-implementation.
- Dantrolene administration time improved by 126.5 minutes, though not statistically significant.

## Abstract

Malignant hyperthermia (MH) seriously threatens perioperative safety. Historically, limited awareness of MH among anesthesiologists and the unavailability of dantrolene have caused a high mortality rate of MH events in China. Although domestic dantrolene has been available in China since 2020, Chinese anesthesiologists continue to face significant challenges in managing MH crises. A WeChat applet–based National Remote Emergency System for Malignant Hyperthermia (MH-NRES) was developed to assist anesthesiologists in making rapid diagnosis, initiating dantrolene mobilization, implementing effective treatment, and subsequently constructing an MH database. However, the effectiveness of MH-NRES in real-world patients experiencing MH in China remains uncertain.

This study aimed to assess the effectiveness of MH-NRES in enhancing outcomes for patients with MH.

A retrospective pre-post implementation study was conducted from January 2018 to November 2024. The MH-NRES intervention was initiated in December 2022. Medical records were reviewed both before and after the implementation of our intervention, encompassing demographic characteristics, anesthesia-related data, treatment details, and clinical outcomes. Descriptive analyses and a pre-post intervention comparison were used to assess the effectiveness of the MH-NRES intervention. The primary outcome was the mortality of patients with MH. The use of dantrolene and the time interval from the MH episode to the administration of dantrolene were considered secondary outcomes. The user activity metrics of MH-NRES were also reported.

After the MH-NRES was launched for public use, the cumulative number of users reached 21,835, with a maximum daily user growth of 689 (median 15, IQR 9‐25). The cumulative page views amounted to 245,740 and the average daily page views were 262.8. A total of 34 patients with MH and 14 patients with MH were retrospectively collected before and after the intervention, respectively. The mortality of patients with MH in the postimplementation group was significantly lower compared with that in the preimplementation group (1/14, 7.1% vs 19/34, 55.9%; P=.002). No significant differences were observed in the early clinical manifestations of MH between the 2 groups. The rate of dantrolene use in the postimplementation group was significantly higher than that in the preimplementation group (11/14, 78.6% vs 15/34, 44.1%; P=.03). The dantrolene available time in the postimplementation group was 126.5 minutes earlier than that in the preimplementation group, but the difference did not reach statistical significance (median 113.5, IQR 54.5‐244.3 vs 240, IQR 105-324 minutes, P=.08).

The MH-NRES aids in improving the timely administration of dantrolene and decreasing mortality rates among patients with MH. This system represents a rare disease perioperative management model and constitutes a specialized perioperative management approach for rare diseases that suits the current medical situation in China.