How do you keep your staff prepared to respond to a rare but potentially deadly event like malignant hyperthermia? We've developed a memory aid that will improve your staff's recall of each phase of diagnosing and treating MH. It's called the Window Pane Learning Grid.

I. Signs and symptoms
The first pane includes the signs and symptoms of an MH crisis, with an upward arrow to represent factors that increase in an MH event: CO2, heart rate, jaw muscle rigidity and temperature.

II. D.R.U.G.
The second pane uses the acronym D.R.U.G. to describe how to administer dantrolene, the only drug known to reverse malignant hyperthermia.

• Dantrolene sodium must be immediately dispensed to the patient. Begin the dosage with 2.5mg per kilogram. Calculate the initial dose by using a 70kg patient, then multiplying 70kg by 2.5mg, which equals 175.
• Reconstitute each vial of dantrolene with 60ml of sterile water, which yields 20mg of dantrolene. To emphasize the number of vials that you must mix to begin resuscitation, divide 175mg — obtained by multiplying 70kg by 2.5mg — by 20mg. You'll need 8.75 vials of dantrolene to start treating the average MH patient. Prepare 9 vials of dantrolene for the initial dose, since full vials must be mixed.
• Continue dantrolene Until the patient's temperature reaches 101 ?F, or 38.3 ?C. Cooling the body temperature any further runs the risk of developing hypothermia as the patient continues to recover.
• Group supplies so you can quickly locate them to reconstitute dantrolene. Bag the sterile water, 60cc syringes and infusion pins, with mixing instructions printed on the bag. This lets your nurses reach in the MH cart and access the necessary items to dilute dantrolene, and have instructions readily available.

III. C.O.L.D.
The third pane (C.O.L.D.) includes a series of critical treatment steps to follow:

• Cancel the anesthetic gases and depolarizing muscle relaxant, as MH is caused by exposure to triggering agents such as anesthesia and/or succinylcholine. At minimum, change the anesthesia circuit (some facilities change the anesthesia machine entirely).
• Provide 100% Oxygen to the patient once you've canceled anesthesia.
• Cold Liquids are an integral part of MH treatment. Switch IV fluid to refrigerated 0.9% saline, and begin irrigation of any areas possible. Irrigate the surgical wound with cold saline. If you irrigate the stomach with cold saline and are using esophageal probes to monitor temperature, assess temperature in an alternative area. Place ice on the patient's axillas and groins. You may use cold packs from the OR's freezer instead of ice to cool the patient. The bladder may be irrigated as well, but assess hourly urinary outputs, and consider a Foley temperature catheter to monitor the patient's temperature. You may also consider cold rectal lavage.
• Treat Dysrhythmias. During an MH crisis, there is increased cardiac demand and alterations in the electrolyte potassium, which can lead to cardiac ventricular arrhythmias. Administer amiodorone or lidocaine to treat arrhythmias.

IV. M.H.A.U.S.
The last pane of the grid uses the mnemonic M.H.A.U.S. to define the remaining elements of MH treatment. The acronym also stands for Malignant Hyperthermia Association of the United States, an organization that supports healthcare providers handling resuscitation events, and offers post-event support to the patient and family as well. Your team can call (800) 644-9737 anytime during an MH crisis to speak to an MHAUS expert.

• Monitor electrolytes. Send electrolytes to the lab, and initiate treatment to correct any abnormal values. Group and label lab supplies. This includes labeling colored blood tubes with the appropriate tests, to enable rapid and accurate testing in an emergent situation.
• Hyperkalemia is the cause of cardiac arrhythmia, and requires treatment. Administer insulin and glucose to the patient to push potassium back into the cell while assessing electrolytes to determine the extent of treatment.
• Arterial blood gases (ABGs). Acidosis, both respiratory and metabolic, occurs during an MH event. Administer sodium bicarbonate and ventilate the patient with 100% oxygen to treat this condition.
• Urine may be coffee-colored, as kidney function is affected during an MH crisis. Insert a Foley catheter with a urimeter to monitor urine output. Have Lasix and mannitol available on the MH cart in case increasing output is required. Send urine specimens to the lab to assess for myoglobin urea.
• Significant others and family members of the patient should be a priority during an MH event. Assign a team member to update the patient's family. Remember that patients inherit the trait for MH, and family and genetic counseling may also be necessary. Refer the patient and family to MHAUS for counseling after an occurrence of MH.

Preparing for positive outcomes
Malignant hyperthermia is a true perioperative emergency. Effective resuscitation efforts depend on the patient care team's ability to diagnose and recall treatment protocols. Share this memorization technique with your staff to aid retention of important diagnosis and treatment steps. With the right preparation, education and a well-orchestrated treatment plan, your staff can manage an MH event toward a positive patient outcome.