1. TREATMENT OF MALIGNANT
HYPERTHERMIA IN AN OUTPATIENT
SURGERY CENTER
Are you prepared?
Presented by Kelly Parkes Wilson, RN, LHRM

2. WHAT IS MALIGNANT HYPERTHERMIA?
 “Malignant Hyperthermia (MH) is a biochemical chain
reaction response triggered by commonly used general
anesthetics and the paralyzing agent succinylcholine,
within the skeletal muscles of susceptible individuals.”
- MHAUS.org
 MH is a rare but deadly hypermetabolic event.
Complications include cardiac arrest, brain damage,
internal bleeding, organ system failure and death, due to
cardiovascular collapse.

3. PATHOPHYSIOLOGY OF
MALIGNANT HYPERTHERMIA
 Patients susceptible to MH have a defective calcium
channel on the sarcoplasmic reticulum of the skeletal
muscle cells.
 Symptoms arise from hypermetabolism of skeletal
muscles, probably as a result of uncontrolled release of
calcium from the sarcoplasmic reticulum and calcium entry
from the extracellular space or decrease in calcium uptake.
 Resulting in sustained, uncoordinated muscles contraction
and metabolism increases, massive oxygen consumption
and production of lactic acid, heat and carbon dioxide.

4. PATHOPHYSIOLOGY OF
MALIGNANT HYPERTHERMIA
 Rapid ATP consumption
 Cellular acid content increases
 Cell membranes breakdown
 Muscle break down begins (rhabdomyolysis)
 Cardiac changes - tachycardia and dysrythmia,
hypotention, decreased cardiac output, cardiac arrest.
 Lab indicators
 Creatine kinase – high levels indicate muscle
breakdown
 Potassium (hyperkalemia) – leads to cardiac arrest

5. WHO IS SUSCEPTIBLE?
 So who is susceptible?
MH is inherited with an autosomal dominant inheritance
pattern linked to as many as 80 genetic defects.
Carriers with susceptibility often are unaware they are
at risk.
 The rate of occurrence is estimated to be as frequent
as 1 in 200 cases or as rare as 1 in 65,000.
 Children and young adults are at greater risk.
 As many as 5% do not survive an MH event.
 A susceptible patient may have previous surgeries,
exposed to triggering agents, without a reaction but
have an MH crisis in subsequent exposure.

6. SO WHAT ARE WE DOING TODAY?
The goal of today is to address how an MH crisis
would be treated at this facility.
Prevention:
 Preoperative questions & planning
Recognition
 Recognize signs and symptoms
Treatment:
 Response/duties cards
 Introduction to the emergency cart.
 Walk through a mock code.
Transfer:
 Discuss transfer protocol.

7. PREVENTION:
PREOPERATIVE QUESTIONING
 It is important to ask questions regarding the
patient’s anesthesia & health history as well as
family member’s history.
 If there is any concern or red-flag regarding
susceptibility to MH, contact the anesthesia
provider.
 Preparation for a possible MH patient is critical.
 Prevention is the best treatment!

8. PREVENTION:
PREOPERATIVE QUESTIONING (CONTINUED)
 History and Physical appointment should ask about any
anesthesia problems in the patient’s past or any family
members’ past. The conversation should include
questions to exploring the subject of MH.
 Has you ever had a “bad” reaction to anesthesia?
 Have you or a family member had a problem with
anesthesia?
 Have you or a family member had a fever while under
anesthesia?
 Has a family member died unexpectedly in the OR?
 Have you or anyone in your family experienced a heat stroke
that resulted in hospitalization?
 Have you ever noticed dark “cola-colored” urine after general
anesthesia or after a heat-related illness?
 Do you or anyone in your family have a neuromuscular
disorder?

9. TRIGGERING VS. “SAFE” ANESTHETICS
Triggering Agents Non-triggering Agents
 Volatile gaseous  All others are safe
inhalation anesthetics  Propofol
 Isoflurane
 Ketamine
 Sevoflurane
 Desflurane  Nitrous oxide
 Halothane  Alllocal anesthetics
 Enflurane  Allnarcotics
 Methoxyflurane  Non-depolarizing
muscle relaxants
 Succinylcholine  Vecuronium
 (Anectine)  Rocuronium
 Pancuronium

10. PREVENTION:
PREOPERATIVE PLAN
 Malignant hyperthermia can be avoided by eliminating
triggering agents. Educate the patient that, if they are a
susceptible patient, that does not mean his/her case
would be cancelled.
 Patients CAN have outpatient surgery even if they have
had previous MH event or a family history.
 Talk to the anesthesia provider if you have a patient you
are concerned about.
 Have a plan, have appropriate supplies, educate and
practice.

11. PATIENT WITH KNOWN OR SUSPECTED MH
HAVING ELECTIVE SURGERY
 Patients can have had an uneventful anesthesia in
the past but still have an MH reaction in a later
surgery. Do not assume there will be no MH
reaction if the patient had an uneventful surgery
before.
 Dantrium (dantrolene) capsules are available as a
prophylactic for patient with suspected MH, but not
widely used. Decision would be made by
anesthesia provider to use prophylactic treatment.
Avoidance of triggering agents is primary
prophylactic approach.

12. PATIENT WITH KNOWN OR
SUSPECTED MH HAVING OUTPATIEN
SURGERY (CONTINUED)
 Pre-inform anesthesia provider.
 Schedule as first case of the day.
 No Triggering Agents to be used!!
 Be prepared with dantrolene& MH cart.
 Closely monitor early signs of MH.
 Any patient suspected of MH should remain in
PACU for 4 hours for monitoring.
Testing is available at special centers. Susceptibility is
determined by the caffeine-halothane contracture test which
involves taking a biopsy of skeletal muscles. Information
regarding testing can be found at www.MHAUS.org.

13. EARLY RECOGNITION OF MH
 Generally first diagnosed by anesthesia provider
 Early diagnosis is critical for patient survival
 MH symptoms can initiate in PACU
 Signs and symptoms
 Elevated end tidal CO2 or tachypnea
 Increase oxygen consumption
 Tachycardia & PVC’s
 Cardiac arrhythmia
 Unstable blood pressure
 Sweating, mottled skin
 Masseter spasm
 Generalized muscle stiffness or rigidity
 Metabolic and respiratory acidosis

14. LATE SIGNS & SYMPTOMS OF MH
 Elevated temperature
 Temperature can increase 1.8° F every 3 minutes
 Metabolic and respiratory acidosis
 Presence of creatine kinase
 Hyperkalemia
 Hypercalemia
 Dark urine (myoglobinuria – myoglobin in urine)
 Severe cardiac arrhythmia and cardiac arrest
 Disseminated intravascular coagulation (DIC)
 Left ventricular failure – pulmonary edema - death

15. PROMPT TREATMENT
 Early Treatment – Anesthesia will run the crisis!
 Dantrolene mixed and administered quickly .
 Initiate transfer protocol.
 Effective Treatment
 ALL HANDS ON DECK!
 Working as a prepared team.
Act Quickly…SAVE A LIFE

16. TREATMENT: EMERGENCY ABCD’S OF
MALIGNANT HYPERTHERMIA
A =
 Agents – stop all triggering agents
 Administer non-triggering anesthetics
 Ask for help
 Ask for MH Cart
B = Breathing – hyperventilation with 100%
oxygen
C = Cooling procedures if patient is > 102.2
D = Dantrolene – continuous rapid IV push

17. USE YOUR RESOURCES -
YOU’RE NOT ALONE!
 Call for all nurses to report to the OR!
“Code MH” (or other designated code)
 Call the 1-800 644-9737 to speak to MHAUS
Hotline. Anesthesia provider should speak with
them on a cell phone.
 Pull MH Emergency Response Cards and assign 4
nurses their duties.
 MHAUS wall posters available from MHAUS.

18. TREATMENT:
EMERGENCY RESPONSE CARD

19. CIRCULATING NURSE
 Call for help – assign nursing duties (dantrolene,
medication and cooling nurse).
 Assign someone to call 911….critical step!
 Assign someone to inform other anesthesiologist if
available. NO NEW CASES TO START IN THE
OTHER ORs – ALL HELP NEEDED FOR MH
CRISIS
 Assign someone to notify the surgery center
manager and/or administrator of the situation.

20. CIRCULATING NURSE
 Assist anesthesia as needed to:
 Call MHAUS – number on treatment cards
 Change circuit & soda absorbent (have with MH
supplies).
 Start large bore IV – discontinue LR and hang N/S.
 Draw labs/urine specimen.
 You are still circulating so keep the surgery in mind.
Help the surgeon/scrub close or pack for transfer.
 What you cannot do – DELEGATE!

21. DANTROLENE SODIUM
- THE drug for MH
 Dantrolene acts as a skeletal muscle relaxant by acting
on calcium channels, suppressing the rise of calcium in
muscle cells that trigger the MH response.
 Dantrolene is generic name. Dantrium and Revonto are
name brand.
 Reconstitute with preservative-freesterile water.
 Each facility should have 36 vials on hand, located close
to the OR, with code cart is logical location. Sharing
vials with other facilities is not recommended.
Average of 30 vials used per crisis.
 IV Dantrolene treatment will continue during
transportation and up to 36 hours in ICU.

22. DANTROLENE NURSE
 Obtain code cart if not already in the OR.
 Start mixing dantrolene (skeletal muscle relaxant).
 Each vial has 3g of mannitol included (renal vasodilator).
 Mix with preservative-free sterile water
 60ml sterile water per dantrolene vial
 Create a fluid path with short IV tubing and stopcock for
rapid mixing.
 Use spikes for rapid injection into vial
 Shake until clear - 2 ½ - 4 minutes to mix. (New quick-
mixing versions make reconstitution much easier and
quicker).

23. DANTROLENE NURSE
 Get all the help that you can to mix the dantrolene. A
minimum of 2-4 people needed.
 Rapid IV push of dantrolene once diluted.
 Initial dosing of dantrolene = 2.5 mg/kg (20mg/bottle)
 Quick conversion dosage chart located on MH cards
Weight Initial Dose via rapid IV push
 110lb = 50kg 125mg 6.25 vials
 132lb = 60kg 150mg 7.5 vials
 154lb = 70kg 175mg 8.75 vials
 176lb = 80kg 200mg 10 vials
 198lb = 90kg 225mg 11.25 vials
 220lb = 100kg 250mg 12.5 vials
 Send dantrolene vials with patient during transfer for
continued treatment.

24. MEDICATION NURSE
 Therapy aimed at treating hyperkalemia, acidosis,
arrhythmia and increasing urinary output.
 Medications to be prepared to give
 Sodium Bicarbonate (treat metabolic acidosis)
 Furosemide (increase urinary output)
 Dextrose (treat hyperkalemia)
 Calcium chloride (treat hyperkalemia)
 Regular insulin (treat hyperkalemia)
 Lidocaine (treat arrhythmias)
 Amiodarone (treat arrythmias)

25. MEDICATION NURSE - DOCUMENTATION
 Record keeping
 Assign recording to another person if available
 Specialized “Malignant Hyperthermia Critical
Intervention Record” is available from MHAUS
 Complex form – be familiar with the form before you
need to use it
 Focus documentation on:
 Medications given
 Time given
 Dosage
 Patient response
 Nursing interventions
 Cooling measures

26. COOLING NURSE
 Discontinue warming blanket if in use.
 Provide anesthesiologist with an esophageal
temperature probe (should be with MH supplies).
 Cooling protocol starts at 102.2°.
 Patient warms at a rapid rate so begin gathering
cooling supplies even if patient is not at treatable
temperature.

27. COOLING NURSE
 Cooling techniques:
 Cold IV and bottled sterile saline in refrigerators.
 Cool the patient surface by putting ice packs to groin,
axillea and head
 Be prepared to lavage stomach, bladder and rectum
with cold saline.
 Provide cold sterile saline for lavage of open cavity.
 Discontinue cooling measures when temperature
decreases to 100.4 °> to avoid hypothermia.

28. SO, WHAT’S MY JOB?
 You do not know which job you will have during an
MH event so you must be familiar with all 4 nurse
assignment.
 All 4 nurses’ responsibilities will be important and
stressful.

29. CODE & MH CART
 Keep it stocked and organized.
 Take time to go through the cart and be familiar with
the contents.
 Keep ice available.
 Cold saline in refrigerator.

30. WHAT’S SHOULD BE IN
EMERGENCY CART?
Medications Supplies
 Dantrolene – 36 vials  Anesthesia circuit and
 Sterile preservative free water sodasorb
 Sodium Bicarbonate 8.4% (50ml  Temperature probe
x 5)  60 cc syringes
 Furosemide
 Mini-spikes
(40mg/amp x 4 amps)
 Fluid transfer tubing
 Dextrose 50%
(50ml vials x 2)
 N/G tube & Toomey syringes
for irrigation
 Calcium Chloride
 Foley
10% (10ml vial x 2)
 Zip baggies for ice packs
 Regular Insulin
(100 units x 1 refrigerated)  Large bore IV’s
 Lidocaine preloaded syringes  ICE & 3 Ls of cold IV and
(100mg) x 3 or Amiodorone bottles saline in refrigerator

31. A CLOSER LOOK at MEDICATIONS
 Dantrolene – muscle relaxant
 Sterile preservative free water – for dilution
 Sodium Bicarbonate – treat metabolic acidosis
and hyperkalemia
 Furosemide – maintain urine output
 Insulin & Dextrose - treat hyperkalemia
 Calcium Chloride – treat hyperkalemia
 Lidocaine or Amiodorone - treat dysrhythmias

32. TRANSFER PROTOCOL
 Outpatient surgery centers have the added obstacle
of having to transfer the patient to an inpatient
facility for complete treatment of an MH event.
 Call 911 early to begin transfer process.
 Direct personal communication – anesthesia to
physicians at the hospital – is strongly
recommended.
 Have a “Transfer of a Patient” protocol in place and
make sure everyone knows where it is and how to
use it.

33. TRANSFER PROTOCOL
 Patient should be moved when, according to
anesthesia, the patient is showing signs of stability.
Anesthesia provider will make decision of timing of
transfer.
 Signs of stability are:
 EtCO2 in declining
 Heart rate is stable or decreasing with no ominous
dysrythmias
 Dantrolene administration has begun
 Temperature is normal or declining
 If present, generalized muscular rigidity is resolving

34. TREATMENT AT A GLANCE
“Some hot dude better give iced fluids fast”
 Stop triggering agent
 Hyperventilate with 100% O2
 Dantrolene
 Bicarbonate
 Glucose and Insulin
 Ice and cooling measures – lavage, surface &
wound
 Fluids – IV fluids in and Lasix for output
 Fast – treat tachycardia/V-tach

35. TIME TO DO A MOCK CODE!
REMEMBER…..
 Take this opportunity to practice without harming a
patient.
 Be comfortable – you’re among friends.
 You can’t make a mistake here.

36. REFERENCES
 AORN Perioperative Nursing Video Library (2009). Video: Malignant
Hyperthermia; Keeping your cool [DVD video]. USA:Cine-Med.
 Helmer, M. & Carlson, K. (2010). Malignant Hyperthermia: Perioperative
crisis [PowerPoint slides]. Retrieved September 27, 2010 from
http://www.nursingceportal.com/CECourses/Description/38
 MHAUS (2010). Guide to malignant hyperthemia in an anesthesia setting.
Available at www.mhaus.org
 MHAUS (2010). Transfer plans for suspected MH patients [poster]. Available
at www.mhaus.org
 Reno, D. (senior editor.) (2008). Perioperative standards and recommended
practices (2008 Ed.). Denver: AORN