The anesthesiologist stirs and looks up at the capnograph, watching as the patient's end-tidal CO2 climbs steadily past 55 mmHg. Not good, he thinks, his brow furrowing with the first traces of concern. He reaches out and tries to open the patient's jaw, but the rigid masseter muscle has forced it shut. The anesthesiologist anxiously glances over his shoulder at the vital signs monitor and zeroes in on the patient's rapidly increasing heart rate, the numbers climbing in concert with the thump, thump, thumping of his own chest.

It's happening.

"We've got an MH event on our hands," he calls out, calmly but forcefully. "Let's move, people. This is the real deal." How long would it take for your team to roll an MH cart into the room, open its drawers and pull together the supplies needed to reconstitute dantrolene, the one drug that can save the patient's life? The difference between pats on the back for a job well done and a long walk to the waiting room could literally depend on how often you make sure your MH cart is fully stocked and properly organized.

Anesthesia providers at Children's Hospital Medical Center in Omaha, Neb., fill the top drawer of their MH carts with medications needed during an emergency response. "Dantrolene is right there, ready for us to start mixing and give right away," says Ryan Hamlin, MD, clinical director of pediatric anesthesiology and a consultant for the hotline of the Malignant Hyperthermia Association of the United States (MHAUS). He points out that there are 2 formulations of dantrolene on the market:

• Dantrium (Par Pharmaceutical) and Revonto (US WorldMeds) come in 20 mg vials that require 60 ml of sterile water to reconstitute. You must stock 36 vials of each formulation, which have shelf lives of 3 years, at a cost of $2,340 for Dantrium and $2,400 for Revonto. Your staff must reconstitute 8 vials of either medication to deliver the initial 2.5 mg/kg dose that's needed to stabilize a stricken patient.
• Ryanodex (Eagle Pharmaceuticals) comes in 250 mg vials that require 5 ml of sterile water to reconstitute. You must stock 3 vials of the drug, which has a shelf life of 33 months at a cost of $8,134. The initial 2.5 mg/kg dose can be administered with a single vial.

"Ryanodex can be reconstituted more quickly and with a smaller volume of sterile water," says Dr. Hamlin. "The active medication is exactly the same as the other drugs, which require quite a bit of elbow grease to ready for administration."

Colleen Bradley, BSN, RN, CNOR, a surgical services staff nurse at UNC REX Healthcare in Raleigh, N.C., agrees that Dantrium and Revento can be challenging and time-consuming to prepare, and that Ryanodex is easier to reconstitute. But you have to decide if it makes sense to pay more for a drug that takes less time to administer in an emergency situation that, in all likelihood, you won't face before it expires. There's no right answer. (MHAUS does not endorse one formulation over the other.)

In fact, UNC REX stocks both formulations. The care team treats patients with Ryanodex during the onset of an MH crisis and, once patients are stabilized and transferred to the ICU, they administer one of the other formulations as maintenance doses while patients are observed for recurrence.

There are other medications you should have available in MH carts, including:

• sodium bicarbonate 8.4% to correct acid-base disturbances;
• insulin to treat high potassium levels;
• dextrose 50% to co-administer with insulin to maintain normal blood sugar levels;
• calcium chloride 10% to protect the heart from severe hyperkalemia; and
• lidocaine and amiodarone to treat cardiac arrhythmia.

Also fill the MH cart with the sterile water needed to reconstitute dantrolene — MHAUS suggests storing the water in 100 vials instead of bags to prevent accidental IV administration — and supplies for administering the emergency response drugs, including needles, syringes and IV catheters.

You want staff members who rush to help during an MH event to arrive at the patient's bedside with a plan and a purpose. The clinical leaders at UNC Rex Healthcare in Raleigh, N.C., developed role cards for the different personnel who respond to the call for help no surgical team wants to make. The laminated cards, which hang on each MH cart in the hospital, include specific directives for various members of the response team. For example:

• Medication nurses bring the MH cart to the patient's bedside and prepare emergency medications for administration, including vials of dantrolene.
• Dantrolene nurses reconstitute and administer the appropriate doses.
• Cooling nurses fill plastic bags with ice and pack them around the patient.
• Charge nurses notify clinical managers about the MH crisis and gather available caregivers to help with the response.

UNC REX also created an MH checklist to guide the staff during a crisis, charts that contain weight-based dantrolene dosage guidelines and an MH documentation record that staff fill out during an emergency response.

"The documentation record also serves as a reminder to complete those tasks," says Colleen Bradley, BSN, RN, CNOR, a surgical services staff nurse at UNC REX. "The purpose of the checklist and the role cards is to decrease our staff's reliance on memory when determining the next steps in an MH crisis response."

— Mike Morsch