Nancy Burden, director of ambulatory surgery for BayCare Health System in Largo, Fla., discusses what MH is and how to detect it and what ASCs can do to prepare for an MH event in their centers.
What is MH?
Malignant hyperthermia is a biochemical chain reaction in the skeletal muscles in response to certain general anesthetic agents and succinylcholine, according to Ms. Burden. During an MH crisis event, a patient's metabolism speeds up, and the body begins to break down skeletal muscle tissue. This eventually results in the textbook extreme rise in body temperature, although other symptoms precede that hyperthermic state.
"It is really the only anesthesia-related 'disease' that exists," Ms. Burden says. "It's tricky because only certain people get [MH], and providers do not often know who those people are. Every once in awhile you will have someone who can describe a personal or family history, but that is rare."
For this reason, patient history and screening are essential. "You need to make sure you ask if the patient or anyone in their family has had an unusual reaction to anesthesia, because it is a genetic disorder triggered by gases and a muscle relaxant used in general anesthesia," Ms. Burden says. "This crisis is especially challenging in children and teens who are having general anesthesia for the first time with a potential triggering agent."
Always be prepared
Because MH is nearly impossible to predict, surgery centers need proper equipment to handle a crisis. Because these events are rare, but devastating, it is essential for every center to be as prepared as possible. Knowing what an MH event looks like and what steps to take to address a crisis is critical.
1. Know the warning signs. According to Ms. Burden, one of the first signs of an MH crisis is increased CO2 production evident through an increase in end-tidal CO2. "Muscle rigidity can also come on suddenly, usually in the jaw or trunk, and heart rate and respiratory function may increase," she notes. In pediatric patients, the first sign can be cardiac arrest.
The Malignant Hyperthermia Association of the United States also lists these additional following warning signs:
- Masseter spasm or trismus
- Tachycardia/tachypnea
- Mixed respiratory and metabolic acidosis
- Increased temperature (may be a late sign)
- Myoglobinuria (breakdown of muscles evident in urine)
2. Carefully monitor patients in the OR. Since early signs are visible in a patient's carbon dioxide production or through other vital signs, monitoring is key to identifying any warning signs of an MH crisis, according to Ms. Burden. "You should make sure that you are monitoring temperature as well during general anesthesia," she says.
3. Educate staff members on responsibilities. "It takes a lot of people to treat an MH crisis, more than in a cardiac arrest. Also, it is a rapidly evolving crisis," Ms. Burden says. One factor is the time it takes to dilute dantrolene, the only agent available to reverse MH, so it can be injected into the patient.
ASCs need to ensure that staff members are educated on what steps need to be taken and what their roles are should an MH event occur, from the surgical staff through the receptionist, Ms. Burden says. Some of the steps to take when an MH event occurs include:
- Immediately stopping the triggering agents
- Calling for outside help
- Administering oxygen, bicarbonates and other cool irrigation agents
- Cooling the patient
- Injecting dantrolene
- Treating cardiac arrhythmias
- Monitoring kidney function
To help staff members remember the procedure, Ms. Burden suggests ASCs post large posters in all areas of what the procedures are for an MH event. MHAUS also provides posters ASCs can use.
4. Keep supplies up to date and accessible. Because MH crises are rare, many ASCs may not have taken stock of their supplies in some time. Ms. Burden advises centers to check their supplies regularly so that they are prepared.
Dantrolene is an essential tool for an MH event, as it is the only drug available to specifically treat the condition. "The current recommended amount of dantrolene that should be kept on hand in locations performing general anesthesia is 36 vials, and the drug comes in boxes of 12. Some ASCs may only keep one box on hand because of cost, but Ms. Burden notes that this is a dangerous practice. Although it is expensive to have the proper supply on hand, it is a small amount for an insurance policy for patient safety. The drug is now manufactured by more than one provider, which may help with the cost," she says.
The teams at Ms. Burden's company have developed MH carts at their centers that act as a back up to the code cart. Carts include supplies, such as the dantrolene, a small refrigerator to keep cold irrigations and IV fluids, tubings and irrigation sets, and phone numbers of the correct contacts at local hospitals and ASCs should the center need to secure more dantrolene. A script is included by the phone numbers so that any staff member can call. This keeps everything in one location, so it is easy to retrieve in case of an emergency. Centers should also plan ahead for the fastest method of transporting dantrolene from another facility.
Other nonclinical concerns can also affect an ASC's success in treating an MH crisis, according to Ms. Burden. "You need to make sure that your OR telephones can dial long-distance numbers," she says. "Many times centers will want to limit long distance in their facilities, but in an emergency, you will need to dial outside for help, particularly the emergency MHAUS hotline number to speak with a physician expert during a crisis." That number is 1-800-MH-HYPER or 1-800-644-9737.
A working ice machine is essential for cooling a patient during an MH crisis. But the center should also consider the potential for needing backup for ice. Consider the availability of petty cash so that a business office staff member could quickly purchase ice if needed.
5. Run practice drills at least annually. The best way to prepare for an MH event is to actually run through it, according to Ms. Burden. A drill can help staff members know their exact role in an MH crisis, which can help reduce mortality in the situation, she notes. MHAUS sells a mock drill kit that ASCs can use, and Ms. Burden suggests practicing dilution with expired vials of dantrolene.
In addition to the mock code, include competency testing once a year where staff members verbally describe what they will do in an MH event. "We never want to have this crisis happen," she says, "but it is imperative to be prepared if it does."
6. Plan for the ongoing care of the patient. Afterward, the patient will need to be transported to a hospital for further treatment and for observation in case of recurrence, so ASCs will need to prepare for the next steps once the patient is stabilized, according to Ms. Burden. The Ambulatory Surgery Center Association has recently teamed with MHAUS to provide guidance for ASC to hospital transfer protocols.
Learn more about the Malignant Hyperthermia Association of the United States.