Did you know the ORNAC Standards recommends review of Malignant Hyperthermia management as an Annual continuing professional development?
It can be difficult to gauge how much we know so here are some knowledge reflection questions that might help:
- Do you feel well versed in MH management?
- Does your unit support annual education that addresses MH specifically?
- Do you have experience reconstituting Dantrolene?
- Do you have access to readily available MH resources?
If you’ve answered no to any of these questions, you’re definitely in the right blog post!
MH is a genetic abnormality of muscle metabolism initiated by certain triggering agents resulting in a hypermetabolic state. MH is precipitated by certain general inhalation anesthetics, depolarizing skeletal muscle relaxants, and stress.
A study of the clinical manifestations of MH in North America from 1987 to 2006 noted that almost 75% of MH presented in males and almost 70% of those incidences in Caucasian populations. The study showed that the most commonly presenting clinical symptom is hypercarbia followed by sinus tachycardia and masseter spasm; additional signs and symptoms include generalized muscle rigidity, unstable blood pressure, tachypnea, mixed respiratory and metabolic acidosis, myoglobinuria, hyperkalemia, and fever that may exceed 110° F (43° C). Research shows that time from induction to first sign of MH was less than 30 minutes in the majority of cases. Once the acute episode is treated in the OR, the patient may be admitted to the PACU. Because successful management of MH depends on early assessment and prompt intervention, the PeriAnesthesia nurse must be knowledgeable in the pathophysiology and treatment of this syndrome.
Resources include:
Malignant Hyperthermia Association of the United States (MHAUS) (www.mhaus.org)
North America MH Registry of MHAUS (www.mhreg.org).
Review of Unsafe Anesthetic Agents for Patients With MHS
Inhaled General Anesthetics
- Desflurane
- Enflurane
- Ether
- Halothane
- Isoflurane
- Methoxyflurane
- Sevoflurane
Depolarizing Muscle Relaxants that Trigger MH
- Succinylcholine
Dantrolene Sodium (Dantrium)
Dantrolene, the primary pharmacologic agent used in the treatment of MH, is a muscle relaxant chemically and pharmacologically unrelated to other muscle relaxants. It is the only known pharmacologic effective in the treatment of MH. When it is used in the treatment of acute MH, the intravenous dosage is 1 to 2 mg/kg, which can be repeated every 5 to 10 minutes with a maximal dose of 10 mg/kg. If the acute episode of MH occurs in the OR and the patient is treated successfully, dantrolene therapy is continued into the recovery (PACU) period to prevent recurrence of MH. After the acute period in the PACU has passed, the patient is given oral dantrolene in four divided doses.
Because dantrolene is poorly soluble, it is supplied in vials in the form of a lyophilized powder. To reconstitute a vial of lyophilized powder, 60 mL of sterile water for injection is added to the vial and is shaken until the solution is clear; many compatibility problems arise when dantrolene is mixed with solutions other than sterile water for injection. Also, the sterile water for injection used to reconstitute the dantrolene should not contain any bacteriostatic agents because it is not unusual to use more than 2000 mL of diluent during the treatment of acute MH in an adult who weighs 70 kg. A new form of rapidly dissolving dantrolene (Ryanodex) became available for clinical use in 2014. Supplied in 250-mg vials, it can be reconstituted with only 5 mL of sterile water, and warming is not needed. Therefore, an initial dose can be administered to the patient within 1 minute. However, Ryanodex is more expensive, has a shorter shelf life, and requires supplementary doses of mannitol.
Please visit the Malignant Hyperthermia Chapter inside Drain’s PeriAnesthesia Nursing, A Critical Care Approach (7th Edition) here: Drain’s PeriAnesthesia Nursing | R2 Digital Library (oclc.org) for a more in depth review of MH.
We would love to hear about your experiences with MH or mixing dantrolene – as a community we can learn a lot from each other’s experiences!
References
Odom-Forren, J., Teton Data Systems (Firm), & STAT!Ref (Online service). (2018;2017;). Drain’s perianesthesia nursing: A critical care approach (Seventh;7; ed.). Elsevier
Great update! Thanks
We had a fun in-service recently for mixing Dantrolene. Works well on the days when you have smaller amount of staff or room closures, i.e. resident research day, spring break, etc. I divided staff into two teams. First team to successfully mix three vials and bring them to me was the winner. Objectives for in-service included discussing team dynamics and role assignment. Imagine this: the team that assigned roles was the winning team! We also discussed how to access more Dantrolene when pharmacy is closed. I encouraged staff ahead of time to come up with team names, and one team showed up in team colors. Winners had coffee on me, losers received whoopie cushions from the dollar store. Our unit manager (male) dressed up as one of the Spartan cheerleaders from SNL.
WOW Linda that sounds fantastic! What a great way to use up expired Dantrolene vials. I love how committed the staff and management were 🙂 It is great that you thought of including discussions on team dynamics and roles as this is often the forgotten, oh so important, factor in the timely management of an MH crisis.
Thank you for the update!