MH PRACTICE DRILLS Let staff members practice reconstituting expired vials of dantrolene.

How do you keep your staff ready to respond to a rare but potentially deadly event like malignant hyperthermia? Practice drills. In 2015, we put together a formal MH response plan and have conducted simulations in each of the past 2 years. During both drills, we exposed a few weak links that should help us improve our ability to respond in the event of an MH crisis. Here's what we learned.

Don't assume your OR team is familiar with MH. Before our first simulation, we learned that most of our staff was unaware of their roles in an MH crisis. We ordered instructional materials from the Malignant Hyperthermia Association of the United States (MHAUS) and updated our existing MH cart according to MHAUS guidelines with the proper drugs, equipment and supplies (osmag.net/ZawGX3). A lot goes into stocking an MH cart. The long list of drugs alone includes dantrolene, sterile water for injection USP, sodium bicarbonate, dextrose, calcium chloride, regular insulin, lidocaine and refrigerated cold saline solution.

We also assigned nurses and surgical techs to take an MH course and conducted an in-service to the entire perioperative staff. This included a PowerPoint presentation — "The ABCs of Managing MH," outlining each team member's role during an MH crisis, from pre-op to post-op, including the need to ask about any personal or family history of MH during patients' pre-admission assessments — and a mock-drill DVD from MHAUS.

Initially, we kept our MH cart in the core area, but the simulations taught us that location wasn't convenient for PACU, ICU or pre-op. We moved the cart out of the sterile area and into a neutral space in the hallway across from the front desk so it's more accessible to anyone in perioperative care.

Our nursing staff had no experience reconstituting dantrolene sodium — the only medication known to reverse the effects of MH — before our yearly drills. Since 2015, they have been using expired vials of dantrolene to practice so they could feel confident handling the most vital aspect of MH response. As you can see in the table below, each of the 3 dantrolene formulations is unique. We've practiced using Revonto and Dantrium. You use 60 mL of sterile water to reconstitute a vial of either 20 mg formulation. You'll need to reconstitute 8 vials of each for an initial dose on a 140-pound patient. There's also Ryanodex, a newer MH drug that contains a much more concentrated dose of dantrolene. To reconstitute Ryanodex, which contains 250 mg of dantrolene per vial, you use 5 mL of sterile water in a single vial, which is all you need for an initial dose.

An effective MH response must reach beyond the OR. The simulations taught us that neither the pharmacy nor the ICU had a firm understanding of MH or their role in the event of a crisis, so we had to conduct additional education — including post-crisis education for pharmacists and ICU nurses — to make sure everyone was prepared.

For the second year, we decided to take the simulation one step further, with a hand-off to the ICU. In a crisis situation, ICU nurses would have to treat an intubated patient and have their post-acute protocols in place: oxygen, ice to bring down the patient's body temperature (but not so much that the patient is at risk of becoming hypothermic) and more dantrolene.

Our first-year simulation ended in the OR once we established that the patient's vitals were good. (Staff from the PACU viewed the simulation in another room by way of video conferencing.) It included 11 people: the surgeon, the anesthesiologist, a CRNA, 3 nurses, a scrub tech, an anesthesia tech, a nurse assistant, a charge nurse and me as the event recorder. The anesthesiologist provided each member with a role card that listed individual responsibilities during the simulation.

Our post-simulation debriefing revealed that although our staff was organized, cohesive and quick to respond, our team leader — the anesthesiologist — identified the need to "close the communication loop." Although individual tasks were promptly delegated, there was no confirmation that these tasks were completed. We also identified the need for additional help during the off-hours.

Now, in a crisis, the team leader will delegate tasks to an individual, and the individual will acknowledge and then report the completion of the task. Also, if an MH event happens during an evening, night, weekend or holiday, the nurse circulator will seek out an administrative coordinator, who can send for additional assistance.

Preparing for an MH event is just one of many drills we have to conduct — other examples include airway drills and fire-safety drills — so drill fatigue can become an issue. That's why we add a new wrinkle each time we run the drill; if you're doing the same drill over and over, your staff might be less receptive and less likely to retain the information. Changing things up can also expose some weak links in your response plan. In our second fire-drill simulation, for example, we decided our patient would be a child, and in the process we learned that our hospital doesn't have a specific ICU for pediatric patients, so we'd need to transfer a child in an emergency situation to another facility for post-acute care.

SAFE THAN SORRY
Do All Facilities Need to Stock Dantrolene?

If your facility solely administers conscious sedation or local anesthesia rather than the volatile anesthetics that might trigger malignant hyperthermia, do you still need to stock dantrolene to treat an MH reaction? Better to be safe than sorry, says anesthesiologist Charles B. Watson, MD, FCCM, a consultant for the Malignant Hyperthermia Association of the United States (MHAUS) hotline.

Don't overlook succinylcholine. The potentially life-saving muscle relaxant used to treat upper airway obstruction can also trigger MH. "When we take away the protective reflexes with drugs like propofol, we sometimes lose the airway," says Dr. Watson.

To treat an MH episode, an initial dose of dantrolene at 2.5 mg/kg is recommended, with a suggested upper limit of 10 mg/kg. If a patient of average weight (about 70 kg) were to require dantrolene at the upper dosing limit, then you'd need at least 700 mg of dantrolene.

MHAUS recommends you stock a minimum of 36 20-mg vials of Revonto or Dantrium, and a minimum of 3 250-mg vials of Ryanodex.

Think of dantrolene as a defibrillator: kept ready for use at all times, even though the need is rare. "No one should feel comfortable that [MH] isn't going to happen to them," says Dr. Watson.

— Bill Donahue

How the 3 MH Antidotes Stack Up

?

Revonto

Dantrium

Ryanodex

Manufacturer

US WorldMeds

Par Pharmaceutical

Eagle Pharmaceuticals

Dantrolene dose per vial

20 mg

20 mg

250 mg

Number of vials for initial dose*

8 vials (520 ml)

8 vials (560 ml)

1 vial (5 mL)

Water to reconstitute 1 vial

60 mL

60 mL

5 mL

Vials required to stock

36

36

3

Price

$2,500

$2,340

$7,500

Shelf life

3 years

3 years

2 years

* Assumes a 143-lb. person at 2.5 mg/kg

Where are we now?
We're well ahead of where we where 2 or 3 years ago. The simulations have helped us close the gaps in our communication and given us the confidence to administer dantrolene. We also know we have the MHAUS Hotline (800-644-9737) at our fingertips, just in case we need help with any of the steps along the way.

Although we conduct readiness simulations annually, staying prepared is a daily event. Every day our staff runs through the MH cart to check expiration dates for the dantrolene and other critical supplies, and also makes sure the lock is intact so we know those supplies are secure in the event of a real crisis. OSM