M

CRISIS CONSIDERATIONS

Crisis Management of

Malignant Hyperthermia in the ORPATRICIA C. SEIFERT, MSN, RN, CRNFA, FAAN; JOYCE A. WAHR, MD, FAHA;

MICHELLE PACE, BSN, RN, CNOR; ADAM B. COCHRANE, PharmD, BCPS;

AARON J. BAGNOLA, PharmD, BCPS

alignant hyperthermia (MH) was first

identified in the 1960s when a patient

with a strong family history of anesthetic

complications demonstrated increased body tem-

perature, a rapid heart rate, and decreased blood

pressure after induction of anesthesia.1 Soon after

this incident, clinicians realized that MH is a hyper-

metabolic state occurring within skeletal muscle

cells that is often triggered by administration of

common general anesthetics, such as halothane,

isoflurane, sevoflurane, desflurane, or enflurane,

alone or in combination with succinylcholine, a

depolarizing muscle relaxant and neuromuscular

blocker.2 Emotional stress, trauma, or strenuous

exercise also can trigger MH.2

During an MH event, a biochemical chain re-

action occurs that is often characterized first by

an unexpected rise in end-tidal carbon dioxide

(ETCO2) and muscle rigidity.1,3-5 Characteristics

of MH include hypercarbia, hypoxia, metabolic

and respiratory acidosis, tachypnea, dysrhythmias,

and an increase in body temperature.2 Although a

temperature increase is the sine qua non of MH,

this sign may be missed early in the course of the

reaction because of the decrease in temperature that

often accompanies anesthesia and surgery. There-

fore, an increase in body temperature, which can

exceed 43.3� C [109.9� F]), is often a later sign of an

MH event.3 This rise in body temperature can increase

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� AORN, Inc, 2014

dramatically by 1� C to 2� C [1.8� F to 3.6� F] everyfive minutes. Sophisticated algorithms have been

added to some anesthesia information systems to

help perioperative personnel recognize a pattern

of temperature change that can herald MH.

The early clinical signs of increased body tem-

perature, increased ETCO2, masseter muscle spasm,

and tachycardia may appear with little obvious

explanation.3,6 Not all patients will present in the

same way; however, clinicians should consider the

presence of MH whenever there are unexplained

signs, such as increased temperature, muscular ri-

gidity, and respiratory or ventilatory problems. In

particular, any increase in temperature requires

immediate consideration of MH. There is a strong

propensity for patient temperature to decrease

during anesthesia and surgery, which is caused by a

variety of factors (eg, cool rooms, redistribution of

core body heat to the skin), but this cooling can be

vasodilated by anesthetic agents.

Untreated MH can produce cardiac arrest, kid-

ney and liver failure, abnormal blood coagulation,

internal hemorrhage, neurologic injury, cardiovas-

cular collapse, and death.4 The goal of treatment in

an MH crisis is to arrest the abnormal metabolic

process with dantrolene and to return to normal

temperatures, hemodynamic conditions, and meta-

bolic functions.7 A prompt, targeted, and effective

coordinated response by all surgical team members

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August 2014 Vol 100 No 2 CRISIS CONSIDERATIONS

is necessary to achieve these goals and prevent the

potentially lethal consequences of MH.

PATIENT POPULATION

Malignant hyperthermia can occur in patients who

are young or old, male or female. Patients at risk for

MH often have inherited skeletal muscle abnormal-

ities associated with MH, such as congenital myop-

athies and some muscular dystrophies.4 Susceptibility

to MH is hereditary, with an autosomal dominant

inheritance pattern. In other words, family members

(ie, children, siblings) of a patient with MH suscep-

tibility have a 50% chance of inheriting a gene defect

for MH and becoming MH susceptible. A rare mus-

cular disorder called central core disease, which af-

fects the muscles used for movement, and a muscular

syndrome called King-Denborough syndrome, a

congenital myopathy, are associated with patients

who are carriers of the genetic factors that make them

susceptible to MH.4,8

Carriers of the inherited gene defect for MH may

be completely unaware of the risk of MH unless they

or a family member developed a life-threatening

crisis during anesthesia. It is important to point out

that although the disease is an autosomal dominant

inherited disorder and several genes have been

identified, not all of the gene mutations associated

with MH have been identified. Consequently, if a

patient undergoes testing for known genes and has

a negative result, it does not mean that the patient is

not MH susceptible. The absence of a positive ge-

netic test does not equal the absence of suscepti-

bility. It is also important to know that not everyone

who is a carrier develops an MH crisis on each

exposure to the triggering anesthetics.4

Triggering Agents

An MH response is often triggered during anes-

thetic induction with the identified triggering

agents. Malignant hyperthermia may first occur

after repeated exposure to anesthesia, or it may

occur postoperatively in the postanesthesia care

unit (PACU) or the intensive care unit (ICU).2,5

190 j AORN Journal

In known MH-susceptible patients, the anesthesia

professional should choose a nontriggering anes-

thetic protocol. Table 1 presents safe anesthetic

agents that can be used perioperatively, and Table 2

presents unsafe anesthetic agents that should not be

used perioperatively.4,5 For example, administra-

tion of succinylcholine must be avoided in patients

with Duchenne muscular dystrophy to reduce the

risk of rhabdomyolysis, which is harmful to the

kidneys.4,7,9

According to Gurunluoglu and colleagues, the

incidence of MH episodes during anesthesia is

approximately one in 5,000.7 In one study, 282

(24%) surgical procedures in which MH occurred

were emergency procedures, and in these cases,

succinylcholine was used 3.8 times more often

than another neuromuscular blocker.3

In specialty areas, MH occurred most frequently in

n orthopedic surgery (25.5%);

n ear, nose, and throat surgery (15.7%); and

n general surgery (14.0%).3

The authors of that study noted that succinylcholine

was given 1.9 times more often in these specialty

areas than in other types of surgery.3

Settings

Case reports of patients who were undergoing

cardiac surgery on cardiopulmonary bypass, and

thus mildly hypothermic when they developed MH,

illustrate that MH can occur in a variety of set-

tings.10,11 For instance, MH can occur in settings

that offer both complex procedures (ie, inpatient

units) and relatively minor procedures (ie, outpa-

tient units, office-based suites).2,4 Table 3 illus-

trates considerations for MH crisis preparation in

inpatient, outpatient, and office-based settings.

ACTIONS

Because there are numerous actions and interven-

tions required within minutes of the onset of MH

(eg, obtaining and mixing dantrolene and other

MH emergency medications and cooling supplies,

TABLE 1. Safe Anesthetic Agentsfor Malignant HyperthermiaeSusceptible Patients1,2

Barbiturate and IV anesthetics

n Diazepamn Etomidaten Ketaminen Methohexitaln Midazolamn Pentobarbitaln Propofol

Inhaled nonvolatile general anesthetics

n Nitrous oxide

Local anesthetics

n Articainen Bupivicainen Dibucainen Lidocainen Mepivacainen Prilocainen Proparacaine hydrochloriden Ropivacainen Tetracaine

Narcotics (ie, opioids)

n Alfentaniln Codeinen Fentanyln Hydromorphonen Meperidinen Methadonen Morphinen Naloxonen Oxycodonen Remifentaniln Sufentanil

Muscle relaxants (ie, nondepolarizing neuromuscular

blockers)

n Cisatracuriumn Vecuroniumn Pancuroniumn Rocuronium

Anxiety-relieving medications

n Chlordiazepoxiden Clidinium and chlordiazepoxide

(table continued)

TABLE 1. (continued) Safe AnestheticAgents for Malignant HyperthermiaeSusceptible Patients1,2

n Clonazepamn Clorazepaten Diazepamn Flurazepamn Lorazepamn Midazolamn Oxazepamn Temazepamn Triazolam

1. Gurunlouglu R, Swanson JA, Haeck PC; ASPS Patient SafetyCommittee. Evidence-based patient safety advisory: malignanthyperthermia. Plast Reconstr Surg. 2009;124[Suppl 4]:68S-81S.

2. Safe and unsafe anesthetics. Malignant Hyperthermia Association ofthe United States. http://www.mhaus.org/healthcare-professionals/be-prepared/safe-and-unsafe-anesthetics. Accessed June 10, 2014.

CRISIS CONSIDERATIONS www.aornjournal.org

increasing the fraction of inspired oxygen [FiO2]

and ventilation), it is important to have adequate

personnel and sufficient supplies, including an MH

code manager whose sole responsibility is to manage

the MH crisis and direct the human and material

resources. A common early sign of MH is an in-

crease in ETCO2 or an increase in body tempera-

ture, which makes it most likely that the anesthesia

professional will be the first team member to suspect

MH. The first action of the anesthesia professional

should be to requestdloudly and clearlydthe

emergency MH supplies, usually in the form of an

MH cart containing, among other items, dantrolene

and sterile water, which is required for mixing the

dantrolene (Table 4).

Identify the Team Leader

Because of the speed with which MH will cause

derangements in multiple organ systems, it is

important to identify a team leader early on. This

individual should not be the surgeon, the RN

circulator, or the anesthesia professional assigned

to the procedure, but should be an individual

who can stand quietly and observe and supervise

while others actually implement the necessary steps

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TABLE 2. Unsafe Anesthetic Agentsa forMalignant HyperthermiaeSusceptiblePatients1,2

Inhaled general anesthetics

n Desfluranen Enfluranen Isofluranen Sevoflurane

Depolarizing neuromuscular blockers

n Succinylcholine3

a Known triggers in malignant hyperthermiaesusceptible patients arevolatile anesthetic agents and depolarizing muscle relaxants.

1. Gurunlouglu R, Swanson JA, Haeck PC; ASPS Patient SafetyCommittee. Evidence-based patient safety advisory: malignanthyperthermia. Plast Reconstr Surg. 2009;124[Suppl 4]:68S-81S.

2. Safe and unsafe anesthetics. Malignant Hyperthermia Association ofthe United States. http://www.mhaus.org/healthcare-professionals/be-prepared/safe-and-unsafe-anesthetics. Accessed June 10, 2014.

3. QuelicinTM: Warning: risk of cardiac arrest from hyperkalemic rhab-domyolysis [package insert]. Hospira, Inc; Lake Forest, IL: SandozPharmaceuticalsCorp; 1993. http://www.accessdata.fda.gov/drugsatfda_docs/label/2010/008845s065lbl.pdf. Accessed June 10, 2014.

August 2014 Vol 100 No 2 CRISIS CONSIDERATIONS

(eg, change ventilation, perform iced lavage, draw

blood gases, start IVs).

The surgeon must focus on the patient and assess

the patient’s surgical status immediately for possible

options: stop surgery, ensure hemostasis, and assess

areas within the patient’s body that could be used

for cooling lavage. If surgery has not started, the

surgeon and other scrubbed personnel can focus

their attention on restoring normal hemodynamic

parameters.6 The anesthesia professional is focused

on administering dantrolene and other anesthetic

considerations. The RN circulator is engaged in

multiple activities, such as calling for help, assist-

ing with dantrolene preparation, and obtaining

supplies. Establishing an independent supervisor

is the best way to facilitate a successful outcome.

Mix and Administer Dantrolene

The primary focus of the surgical team must be

obtaining, mixing, and administering dantrolene.

Without proper and prompt treatment (ie, quickly

delivering dantrolene), mortality is extremely high.

All members of the surgical team need to know

192 j AORN Journal

where the MH cart and dantrolene are kept; if there is

no MH crisis cart, then personnel must be aware of

the location of dantrolene and associated supplies.

Any member of the team can call for additional help.

In this type of crisis, the circulator is the best in-

dividual to call for help via the telephone or the

facility’s emergency system, request the MH cart or

kit, and call for additional personnel. It should be

stressed that additional personnel are vital because

of the many actions required immediately and almost

simultaneously, and most specifically because dan-

trolene is supplied as a powder that must be mixed

with sterile water. Typically, it requires two to three

people simultaneously mixing dantrolene to get the

first critical dose prepared and administered.

The Malignant Hyperthermia Association of

the United States (MHAUS)4 recommends that

the MH cart be stocked with at least 36 vials of

dantrolene and enough sterile water for dilution.

Note that sterile water is a potentially dangerous

agent to be stocked with typical IV solutions

and should be clearly labeled. In addition to the

extra hands needed for dilution of dantrolene, the

anesthesia technician should be called to provide

additional supplies (eg, change the carbon dioxide

[CO2] canister when appropriate, bring extra IV

supplies), and additional anesthesia professionals

also should be called.

Reverse Muscle Contractions

Currently, dantrolene is the only medication

approved to treat an MH crisis by reversing the

MH-related muscle contractions.4 Because prepa-

ration of dantrolene is time-consuming and requires

multiple vials, at least two team members should

be devoted to preparing the medication. The IV

injections should be administered rapidly through a

large-bore IV.

Dantrolene preparation involves the following12-15:

n obtaining dantrolene 70-mL vials, each con-

taining 20 mg of dantrolene;

n diluting and mixing each dantrolene ampule

with 60 mL of sterile, preservative-free water;

TABLE 3. Malignant Hyperthermia Crisis Preparation by Setting

Inpatient facility1,2

n Identify patient information to help recognize the risk of a perioperative malignant hyperthermia (MH) event: previous surgicalanesthetic records, relevant laboratory results or genetic profiles, and associated inherited metabolic abnormalities.

n Plan for pharmacological resources: medications (ie, dantrolene) and personnel (ie, pharmacists).n Locate facility-specific emergency policies and procedures, including an MH protocol.n Locate information for accessing emergency resources, including medications, sterile water, chilled solutions, and contact

information for the Malignant Hyperthermia Association of the United States (MHAUS).n Locate laboratory and blood bank supplies, including laboratory testing tubes and labels, arterial blood gas supplies, rapid

infusion and lavage devices and tubing, and pressure bags.n Identify personnel to support perioperative teams, including personnel to mix dantrolene, surgical first assistants and scrub

personnel to assist with lavage and other methods of chilling the patient, an anesthesia technician, additional perioperativepersonnel (eg, pharmacists, transporters, housekeepers, runners), and additional administrative personnel (eg, charge nurse,chaplain).

Outpatient facility

n Outpatient preparation is comparable to inpatient preparation except that fewer resources and personnel may be available(eg, limited medications, fewer personnel, limited laboratory testing capabilities).

n Identify sources of additional dantrolene.n Transfer to a tertiary care center may be required.

n The necessary steps should be identified before a full-blown crisis occurs, put into a formal policy and procedure, andmade quickly available when needed.

n The steps of the process should include the following:1. Recognize the signs and symptoms of MH.2. Discontinue triggering agents.3. Decide when to transfer the patient.4. Ensure that the transport carrier is capable of treating a patient experiencing an MH crisis (eg, able to provide intensive

care unitelevel care, support ventilation, administer IV medications).5. Ensure that the receiving facility is capable of treating MH and providing intensive care.6. Speak directly with the person receiving the patient with MH to facilitate both a safe transfer and an effective receipt of

the patient (generally this requires direct physician-to-physician communication).7. Make an MH report form available to the receiving institution, including MH-related patient details, anesthetic agents

used, and amount of dantrolene given.8. Identify patients suspected (but not confirmed) of having an MH reaction, make a plan of care for observing and treating

the patient, and, when in doubt whether a reaction is linked to MH, consider calling the MHAUS MH hotline.9. Ensure that transfer actions and policies are included in the organization’s MH drills.

Physician’s office

n Physician’s office preparation is comparable to preparation in the outpatient setting.n Plan for the need to have additional personnel (eg, other office personnel).

1. Kurtz R. 7 Best practices for an effective malignant hyperthermia transfer plan. Becker’s ASC Review. 2011;2011(5):43. http://www.beckersasc.com/asc-accreditation-and-patient-safety/7-best-practices-for-an-effective-malignant-hyperthermia-transfer-plan.html. Accessed June 10, 2014.

2. Have a plan for malignant hyperthermia. OR Manager. 2010;26(1):1-4. http://www.ormanager.com/wp-content/uploads/pdf/ORMVol26No1ASCMalignantHyperthermia.pdf. Accessed June 10, 2014.

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TABLE 4. Malignant Hyperthermia Supplies1

Malignant hyperthermia (MH) cart suppliesa

n MH crisis flowchart attached to the top of the cartn 36 vials of dantrolenen Dantrolene reconstitution kitsn 36 vials (ie, 60 mL or 100 mL) of sterile, preservative-free IV water for diluting dantrolene (not cystoscopy water)n MH laboratory tube kit, containing syringes for

n basal metabolic panel (ie, Chemistry 7)n sodiumn potassiumn chloriden bicarbonate or carbon dioxiden blood urea nitrogenn creatininen glucose

n chemistry 8 (ie, all the components of a basal metabolic panel plus calcium)n myoglobin (ie, serum and urine)n serum creatine kinasen coagulation studies

n plateletsn prothrombin timen activated partial thromboplastin timen fibrinogenn d-dimer (ie, fibrin degradation test)

n MH help line telephone number attached to the top of the cartn MH policy/protocol attached to the top of the cartn Nasogastric tubes and 60-mL irrigation/evacuation syringes for internal lavagen Rectal tubes for internal lavagen Arterial pressure monitoring linesn Arterial blood gas kitn Venous blood gas kit

Additional supplies

n Ice for plastic bags to place around the patientn Padding to protect the patient’s ears and nose from frostbiten Indwelling urinary catheter kitsn Clipboardn Cold normal saline irrigationn Cold IV saline

a All personnel should know the location of the MH cart and the crash cart in the OR.

1. Managing an MH crisis. Malignant Hyperthermia Association of the United States. http://www.mhaus.org/healthcare-professionals/managing-a-crisis.Accessed June 10, 2014.

August 2014 Vol 100 No 2 CRISIS CONSIDERATIONS

n administering 2.5 mg/kg every five minutes until

symptoms subside, with 10mg/kg being a typical

dose necessary to achieve initial response; and

n replenishing the supply of dantrolene constantly

because patients may have recrudescence sev-

eral times during the next 24 hours and may

require up to a total of 30 mg/kg over 24 hours.

194 j AORN Journal

Surgical team members should note that an average

adult patient weighing 70 kg will require eight vials

and that the upper end of 10 mg/kg would require

35 to 36 vials.

A separate team member should be assigned

to contact MHAUS at (800) 644-9737; MHAUS

representatives have been available to instruct

CRISIS CONSIDERATIONS www.aornjournal.org

the caller on appropriate actions. Additionally,

MHAUS may be contacted online at http://www

.mhaus.org. The web site contains a useful video

that demonstrates the preparation of dantrolene and

other educational materials.

Remove the Triggering Agents

The anesthesia professional’s first step is to stop

the delivery of triggering agents (ie, volatile an-

esthetics) immediately and call for the MH cart.

While awaiting arrival of the MH cart, the anes-

thesia professional often will have been able to

switch to nontriggering agents. If, after arrival of

the MH cart and beginning the process of admin-

istering dantrolene, the anesthesia professional has

not been able to changes anesthetics, the switch can

be made to nontriggering agents at this time.14,15

Many actions occur concurrently, and team mem-

bers can identify actions to be taken while awaiting

the arrival of personnel or supplies needed to

continue treatment. Although there may be changes

to the components of the anesthesia circuit (eg,

the circuit becomes hot to the touch), MHAUS16

stresses that clinicians should not delay treatment

to change the anesthesia circuit or the CO2

absorber.

Increase Oxygenation and Hyperventilate

Increasing oxygenation and “blowing off” CO2

with hyperventilation are important therapeutic re-

sponses to hypercarbia, the common, early sign of a

developing MH crisis.14,15 The muscle contractions

that are a part of the MH crisis result in increased

use of oxygen and subsequently produce lactic

acid and CO2. Therefore, the anesthesia profes-

sional should increase the patient’s FiO2 to 100%

within three minutes of onset of MH and hyper-

ventilate the patient at 10 L/minute or more (ie, two

to four times the patient’s minute ventilation).15

The hypermetabolic state of MH will produce

metabolic acidosis, which the anesthesia profes-

sional can treat by administering bicarbonate to

maintain the patient’s pH at > 7.2.14,15 The anes-

thesia professional will require arterial and venous

blood gas measurements to help maintain the pa-

tient’s pH within a normal range.

Reverse Increased Heat Production

Hyperthermia may be mild during the initial stages

of an MH crisis, but it can become severe rapidly.

Cooling measures should be instituted quickly,

and the team leader should direct one or more

team members to collect the necessary supplies and

equipment. Hyperthermia must be treated promptly

and aggressively when the patient’s temperature

is greater than 38.5�C (101.3

�F).14,15 Cooling

interventions recommended by experts include

the use of cooling blankets and hypothermia ma-

chines, gastric lavage, and externally placed ice

packs.14,15 The team leader should assign team

members to collect chilled solutions and supplies to

irrigate body cavities and incision sites. The anes-

thesia team members can infuse chilled solutions

intravenously and perform nasogastric lavage with

cold water. Members of the scrubbed surgical

team (eg, surgeon, assistant, scrub person with su-

pervision) can lavage open body cavities with cold

fluids. Nonscrubbed nursing personnel can assist

with placing bags of ice on and around the patient,

ensuring that dependent areas (eg, ears, nose) are

well padded, and also can initiate rectal lavage.

When dantrolene dosing has begun, it is im-

portant for team members to monitor the patient’s

temperature. The hyperthermic process can quickly

resolve; therefore, cooling efforts should be stopped

when the patient’s temperature reaches 38�C

(100.4�F) to avoid unintentional hypothermia

and cold injuries.14,15

Treat Electrolyte Disturbances

The sustained muscle contractions of MH cause

cellular death, with the subsequent release of

large amounts of potassium into the circulatory

system. Normally, potassium (ie, an intracellular

electrolyte) helps regulate acid-base balance and

the normal excitability of muscles. An increase

in intravascular potassium (ie, hyperkalemia) can

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August 2014 Vol 100 No 2 CRISIS CONSIDERATIONS

trigger lethal cardiac dysrhythmias, such as ven-

tricular fibrillation.

Other electrolytes (eg, calcium) are also released

into the circulation during an MH crisis. To measure

this, the anesthesia professional will request a variety

of tests of electrolytes and other standard components

of a basal metabolic panel. Other tests for blood gases,

creatine kinase, coagulation factors, and serum and

urine myoglobin, which is released when muscle

cells are destroyed, also may be necessary.

Treat Rhythm Disturbances

Dysrhythmias usually respond to treatment of

acidosis and hyperkalemia. Standard antiarrhythmic

medications (eg, amiodarone, lidocaine)17 can be

used, but nondihydropyridine calcium channel

blockers (eg, verapamil, diltiazem) must be avoi-

ded because these agents interact with dantrolene to

produce severe cardiovascular collapse, arrhyth-

mias, myocardial depressions, and hyperkalemia

with subsequent cardiac arrest.14,15,17

Monitor the Patient

In addition to conducting laboratory tests for arte-

rial and venous blood gases, electrolytes, coagula-

tion parameters, creatine kinase, and urine and

serum myoglobin, it is necessary for the anesthesia

professional to provide ongoing monitoring of the

patient, including end-tidal CO2 and temperature.

Measurement of core temperature is best achieved

with centrally placed catheters and devices: esoph-

ageal, rectal, pulmonary artery, tympanic, naso-

pharyngeal, or oropharyngeal. In the absence of

these methods of measuring temperature, forehead

skin temperature sensors are acceptable.18 The RN

circulator should insert an indwelling urinary cath-

eter to not only measure the quantity and color of

urine output but also to indirectly measure cardiac

function. A reduction in urine output and coffee-

colored urine may indicate renal injury.

Monitor the Patient for Recrudescence

The initial dose of up to 10 mg/kg of dantrolene

is typically very effective in halting the abnormal

196 j AORN Journal

calcium release typical of an MH crisis. As the

temperature begins to return to normal, team

members often turn their attention to treating

acidosis, hyperkalemia, and arrhythmias and can

miss the common recrudescence of MH. Recru-

descence (ie, a recurrence of symptoms or a new

outbreak after a period of remission) can occur at

any time, from soon after the initial response up to

24 hours later, and additional doses of dantrolene

need to be available. If the initial 36 vials are the

only stock of dantrolene, administrators should take

immediate steps to obtain enough dantrolene vials

for another full dose.

Plan for Transfer

The receiving unit in a hospital should be called

and preparations made to receive the patient. When

an MH crisis occurs in the tertiary care setting, the

patient should be monitored in an ICU for 36 to 48

hours afterward because MH may recur within 24

to 48 hours after the initial event.17 If the event

occurs in an ambulatory setting or in a physician’s

office, it is important to provide immediate care

to stabilize the patient and then make a transfer

to a facility with sufficient resources to treat MH

aggressively.

If MH occurs outside a clinical facility or in a

setting unrelated to surgery where there are few

medical resources for treating a person in an MH

crisis, the emergency medical system must be ini-

tiated immediately. However, any medical setting

where MH can occur should stock sufficient

dantrolene to provide a full dose because the pa-

tient must be stabilized before transport.15

Prepare for an MH Crisis

In preparation for a potential MH crisis, all mem-

bers of the surgical team should be aware of their

facility’s guidelines, policies, procedures, and pro-

tocols, as well as the location of emergency carts,

equipment, and medications. Simulations and drills

that educate members of the surgical team to

recognize, treat, and manage an MH crisis in a safe

Figure 1. This flowchart can be used as an educational algorithm when training perioperative personnel abouthow to manage a malignant hyperthermia crisis in the OR.

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Figure 2. Medication doses and treatments for a malignant hyperthermia crisis in the OR.

August 2014 Vol 100 No 2 CRISIS CONSIDERATIONS

environment (ie, one that resembles a clinical sce-

nario without relying on an actual patient for

teaching) have been shown to be an effective

method to promote learning.5,6,11-13 In particular,

interprofessional simulation exercises can be

extremely helpful by allowing team members to

practice the steps in the Malignant Hyperthermia

Crisis Flowchart (Figure 1) as an algorithm in a

nonthreatening situation that does not jeopardize

patient care, similar to advanced cardiac life sup-

port algorithms. In addition to the flowchart, sup-

plemental information related to medication doses

(Figure 2), anesthetics, different settings, and MH

supplies can be used as educational guides when

training perioperative team members to manage an

MH crisis in the OR. These figures and tables can

be used as a guide in concert with the OR Crisis

Checklists described by Ziewacz et al13 and Arriaga

et al6 and with the laminated cards from Ariadne

Labs that address individual crises (eg, hemor-

rhage, MH).14

198 j AORN Journal

PATIENT SCENARIO

John M, a healthy 16-year-old boy, is scheduled for

an appendectomy. During the preoperative assess-

ment, the patient mentions to the RN circulator that

he has a family history of “strange reactions” to

anesthesia. The nurse also notes that the patient

referred to nonspecific neuromuscular problems.

These factors alert the RN circulator to talk with

the anesthesia professional who is reviewing the

medical record. The patient refuses spinal anesthesia,

so succinylcholine is used for rapid-sequence in-

duction to prevent aspiration of gastric contents (ie,

full-stomach precautions).

After prepping and draping the patient, the

entire team participates in the time out, during

which the anesthesia professional notes that the

RN circulator had mentioned the patient’s family

having “strange reactions” to anesthesia. The

surgery begins.

The patient had been slightly febrile, so when

the patient’s temperature begins increasing, the

CRISIS CONSIDERATIONS www.aornjournal.org

surgical team members attribute it to the patient’s

appendicitis. However, after giving the succinyl-

choline bolus, the anesthesia professional notes an

increase in ETCO2 and determines that an MH

crisis is occurring. She immediately alerts the team,

increases ventilation and oxygenation, and starts

a propofol infusion to provide for anesthesia.

During this time, the RN circulator calls for help

and initiates the MH protocol to enable prompt

administration of dantrolene. Three doses are ad-

ministered during the next eight hours. The patient

cools down, and no significant adverse events are

noted.

Questions to Ask

Three important categories of questions apply to

most crises:

n What do you know about the patient?

n What do you know about the procedure?

n What do you know about your available

resources?

Contact Information for the MalignantHyperthermia Association of the United States

Emergency 24-hour hotline numbers:

n Inside the United States: (800) 644-9737

n Outside the United States: þ001-209-417-3722

Nonemergency numbers:

n Telephone: (607) 674-7920

n Fax: (607) 674-7910

Web page: http://www.mhaus.org

Mailing address:

Malignant Hyperthermia Association of the United States

1 North Main Street

Post Office Box 1069

Sherburne, NY 13460

Malignant hyperthermia mobile app https://itunes.apple.com/us/

app/mhapp/id392766134?mt¼8 (available for a fee)

All contact information verified June 10, 2014.

The patient. The preop-

erative assessment is an im-

portant time to learn about

the patient and identify risks.

Any previous reactions to

inhalational (volatile) anes-

thetics and succinylcholine

should be investigated,

prompting the RN circulator

to ask, does this patient have

an increased potential for an

MH crisis? If the answer is

yes, it is important to com-

municate this to anesthesia

and surgical colleagues.

Asking questions about

the patient’s past medical

history is also important for

predicting a potential MH

crisis. If evidence of mus-

cular or neuromuscular

disorders and congenital

conditions associated with MH susceptibility are

identified, clinicians may need to perform a sys-

tems review for determining a differential diag-

nosis. This review should investigate the following

factors for the presence of potential conditions that

may increase the risk of an MH crisis:

n cardiorespiratory: hypoventilation and sepsis;

n endocrine: thyrotoxicosis and pheochromocytoma;

n iatrogenic: exogenous CO2 source (eg, lapa-

roscopy being performed), overwarming, and

neuroleptic malignant syndrome;

n neurologic: meningitis, intracranial hemor-

rhage, hypoxic encephalopathy, traumatic brain

injury; and

n toxicology: radiologic contrast neurotoxicity;

anticholinergic syndrome; cocaine, amphetamine,

or salicylate toxicity; and alcohol withdrawal.

The procedure. Procedural knowledge and re-

view of unexpected events during the surgical

team briefing may identify the risks of and re-

sponses to an MH crisis. In reviewing knowledge

AORN Journal j 199

August 2014 Vol 100 No 2 CRISIS CONSIDERATIONS

of the procedure, perioperative team members

should consider the following questions:

n Did the preoperative briefing allow all team

members to ask questions and address plans

for intervention?

n Do the nurses know the signs and symptoms

of MH?

n Do they know what the treatment is?

n Are team members familiar with emergen-

cycommunication policies, procedures, and

protocols?

n Are the possible interventions for associated

emergency procedures known to personnel (eg,

cold injuries, recurrence of an MH episode in

the PACU)?

Knowledge of a procedure also requires that all

perioperative team members know one another

because the performance of a surgical procedure

requires coordinated interaction among personnel.

Team relationships and characteristics are espe-

cially pertinent during emergency situations be-

cause it is likely that when team members know

one another, they can communicate and function

with each other more efficiently and safely. Some

questions for team members to consider include

the following:

n Do team members know one another?

n Can team members communicate with one

another with ease?

n Are there new team members who are unfamiliar

with the MH emergency procedure (eg, nurses,

surgeons, anesthesia professionals)?

The resources. Team members need to be

familiar with what resources are available and

methods to access these additional resources (eg,

“call for help”) when assistance is needed. Cli-

nicians should know where to locate the OR code

button, the charge nurse, the MH cart, pharmacy

telephone numbers, the MHAUS telephone num-

ber, and support for the anesthesia team. Posters

from MHAUS are available for purchase and outline

the care of patients with MH as well as the steps

200 j AORN Journal

recommended for transferring a patient with MH

from a less resource intensive clinical area to one

that has the resources necessary to treat, monitor,

and maintain the patient’s safety. A mobile app also

has been developed by MHAUS to access treatment

recommendations for dosing dantrolene and for treat-

ing acidosis and hyperkalemia. This app also can be

used as a teaching tool.15

Questions regarding resource allocation may

include the following:

n Has the MH protocol been initiated?

n Do perioperative personnel know the protocol?

If not, do they know how to access it?

n Do perioperative personnel know what supplies

and equipment are commonlyneeded to treatMH?

n Are all personnel aware of and comfortable with

using the MH emergency cart?

n Are there enough personnel available to help

retrieve MH medications, supplies, and other

items (eg, ice)?

n Do perioperative personnel know the pro-

cedures for preparing dantrolene for injection?

Preparing dantrolene for injection is notoriously

difficult and should be practiced and simulated

at least annually during nonemergency meeting

times. Periodic simulations are important for

“hard-wiring” the process of treating MH. Outdated

vials of dantrolene from the pharmacy are a good

source for the purposes of practice mixing the

medication; members of the pharmacy depart-

ment are especially important members of the

perioperative team when simulating MH crises

and practicing MH drills. A video on mixing

dantrolene for injection, “Mixing the antidote:

dantrolene sodium for injection,” is available

from MHAUS at http://www.mhaus.org/videos.19

RESOLUTION

Ideally, the patient is returned to a normal meta-

bolic and hemodynamic state with minimal or no

complications. Because MH can begin during

anesthesia or after surgery, the use of trigger an-

esthetics or succinylcholine in PACUs, emergency

CRISIS CONSIDERATIONS www.aornjournal.org

departments, dental surgery offices, and ICUs should

be monitored carefully.

Knowledge of resources includes being familiar

with methods to access additional help (eg, code

button location, charge nurse, support for the

anesthesia professional and the surgical team).

Although specific considerations for MH emergen-

cies that are associated with nursing, anesthesia, or

surgery are shown in the MH flowchart, it should

be noted (and stressed) that not all activities must

be performed by only one specific team member

(eg, the RN circulator or the surgeon). It is important

to form alliances with colleagues who may become

crucial partners during an MH crisis, including

pharmacists, laboratory personnel, critical care and

emergency department personnel, and others who

may be involved in providing emergent care.

SUMMARY

Malignant hyperthermia in theORis a life-threatening

emergency that demands prompt, effective in-

terventions. Specific applications of MH protocols

and guidelines for perioperative nurses and their

interprofessional colleagues may take several

approaches. Institutions may conduct simulation

exercises that include members of all the related

professions and make checklists6,14 available on

every anesthesia machine for easy reference. In

addition to structured resources, “pearls” that have

been gained frompersonal experienceswithMHcrises

can be invaluable (see Supplementary Table 1 at

http://www.aornjournal.org).

In reality, it is difficult to read a checklist in the

middle of a crisis. Team training, rehearsing appro-

priate actions, and reacting effectively are essential

to preparing health care providers to respond in emer-

gent situations and be able to deliver optimal care.

SUPPLEMENTARY DATA

The supplementary table associated with this article

can be found in the online version at http://dx.doi

.org/10.1016/j.aorn.2014.06.014.

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2

Patricia C. Seifert, MSN, RN, CRNFA,

FAAN, is an RN first assistant at Inova

Heart and Vascular Institute, Falls Church,

VA. Ms Seifert has no declared affiliation

that could be perceived as posing a potential

conflict of interest in the publication of this

article.

Joyce A. Wahr, MD, FAHA, is a professor in

the department of anesthesiology at the Uni-

versity of Minnesota Medical School, Minne-

apolis, MN. Dr Wahr has no declared affiliation

that could be perceived as posing a poten-

tial conflict of interest in the publication of

this article.

02 j AORN Journal

Michelle Pace, BSN, RN, CNOR, is a periop-

erative clinical educator at Wellspan Health

York Hospital, York, PA. Ms Pace has no de-

clared affiliation that could be perceived as

posing a potential conflict of interest in the

publication of this article.

Adam B. Cochrane, PharmD, BCPS, is a

clinical pharmacy specialist in the pharmacy

department at Inova Heart and Vascular Insti-

tute, Falls Church, VA. Dr Cochrane has no

declared affiliation that could be perceived as

posing a potential conflict of interest in the

publication of this article.

Aaron J. Bagnola, PharmD, BCPS, is a clinical

pharmacy specialist in the pharmacy department

at Inova Heart and Vascular Institute, Falls

Church, VA. Dr Bagnola has no declared

affiliation that could be perceived as posing a

potential conflict of interest in the publication of

this article.

SUPPLEMENTARY TABLE 1. Malignant Hyperthermia Pearls of Knowledge

n You cannot have too many helping hands; dantrolene is hard to dissolve into solution, and many things will be going on. Manyhands make light work.

n You cannot have too many hands e repeat, repeat, and repeat. However, there needs to be a clear leader who de-termines what tasks need to be performed and who will do them. This person does not perform tasks but instead standsback and makes sure that every task is being performed. This person needs to be identified early and needs to clearly takethe helm. It will not be the surgeon or the person managing anesthesia; it should be a separate individual whose soleresponsibility is to lead.

n Warmed sterile water diluent may cause dantrolene to go into solution faster. However, it takes time to warm the diluent,which could cause an actual delay in administering dantrolene to the patient. If, however, there is warm sterile water (45� C[113� F]) available for reconstitution, using it may shorten the dissolution time and allow faster administration of dantrolene.

n Think outside the boxduse every orifice and every possible exposure to cool the patient. For example, you can put saline intothe peritoneum and then continue cold saline lavage via nasogastric and the rectum in the intensive care unit with a full bodycooling blanket and ice around the head.

n Keep on keeping ondthe malignant hyperthermia reaction can wax and wane. Just when it appears that the patient’stemperature is controlled, the temperature may start to go up again. Stay the course, “rinse and repeat” as necessary, andyou, the team, and dantrolene will win the day.

n Be sure to “flag” the chart of a patient who has had a suspicious past anesthesia experience or a malignant hyperthermiacrisis.

AORN Journal j 202.e1

CRISIS CONSIDERATIONS www.aornjournal.org