Malignant hyperthermia (MH) is a disease that causes a fast rise in body temperature and severe muscle contractions when someone with the MH gets general anesthesia. MH is passed down through families. Hyperthermia means high body temperature.

1. MALIGNANT
HYPERTERMIA
PRESENTED BY
PANKAJ SINGH RANA
NURSE PRACTITIONER

2. INTRODUCTION
Malignant hyperthermia (MH) is a type of
severe reaction that occurs to particular
medications used during general
anesthesia, among those who are
susceptible. These signs can develop any
time during the administration of the
anesthetic triggering agents. It is difficult to
find confirmed cases in the postoperative
period more than several minutes after
discontinuation of anesthetic agents.

3. CAUSES
1. volatile anesthetic gases, such as halothane, sev
oflurane, desflurane, isoflurane, enflurane
2. depolarizing muscle relaxants suxamethonium
and decamethonium
3. Biological stresses of physical exercise or
heat may be the trigger.
4. exercise and/or on exposure to hot
environments
5. inheritance is autosomal dominant with variable
penetrance

4. SIGN AND SYMPTOMS
The typical signs of malignant hyperthermia are
due to a hypercatabolic state, which presents
as a very high temperature
•An increased heart rate
•Abnormally rapid breathing
•Increased carbon dioxide production
•Increased oxygen consumption
•Mixed acidosis
•Rigid muscles
•rhabdomyolysis

5. DIGNOSIS
Monitoring ETCO2
A rise in end-tidal carbon dioxide concentration
(despite increased minute ventilation).
ABG
Respiratory acidosis is universally present and
many patients have developed metabolic acidosis
at the time of diagnosis

6. Monitoring temperature
Elevation of body temperature is often a late
sign.
Blood Test
A raised creatine kinase level, elevated potassiu
m, increased phosphate (leading to decreased
calcium)
Serum Myoglobin
Raised myoglobin; this is the result of damage t
o muscle cells (rhabdomyolysis )

7. Gene Testing
Analysis for RYR1 mutations
Skeletal muscle biopsy:
Sample is taken from vastus muscle of thigh
under local anaesthesia. Muscle is subjected to is
ometric contracture testing under influence of
caffeine or halothane or both. It produces
exaggerated contracture in susceptible patients.

8. CRITERIA FOR MALIGNANT
HYPERTHERMIA
•A 1994 consensus conference led to the formulat
ion of a set of diagnostic criteria. The higher the
score (above 6), the more likely a reaction
constituted MH.
•Respiratory acidosis (end-tidal CO above 55 mm
Hg/7.32 kPa or arterial Pco above 60 mmHg/7.98
kPa)
•Heart involvement (unexplained sinus tachycardia
, ventricular tachycardia or ventricular fibrillation)
•Metabolic acidosis (base excess lower than -8,
pH <7.25)

9. •Muscle rigidity (generalized rigidity including
severe masseter muscle rigidity)
•Muscle breakdown (CK >20,000/L units, cola
colored urine or excess myoglobin in urine or
serum, potassium above 6 mmol/l)
•Temperature increase (rapidly increasing
temperature, T >38.8 °C)
•Other (rapid reversal of MH signs with
dantrolene, elevated resting serum CK levels)
•Family history (autosomal dominant pattern)

10. COMPLICATIONS OF M H
DIC
Pulmonary Edema
Acute Renal Failure
CNS Damage
Blindness,
Seizures,
Coma,
Paralysis CVS Manifestations
Arrhythmias

11. TREATMENT
Etiologic treatment:
Dantrolene ( 2 – 3 mg/kg IV) as an initial bolus, followed
with repeat doses every 5– 10 minutes until symptoms are
controlled.
Prevent recurrence (dantrolene 1 mg / kg IV every 6 hours
for 72 hours )
Symptomatic Treatment:
Immediately terminate trigger drugs & conclude surgery a
s soon as possible Hyperventilate with 100 % oxygen

12. Initiate active cooling
Iced saline 15 ml / kg every 10 minutes
Gatric lavage with iced saline
Surface cooling
Use of alternative medication
local anesthetics (lidocaine, bupivacaine, mepivacaine),
opiates (morphine, fentanyl), ketamine, barbiturates, nitrou
s oxide, propofol, etomidate, and benzodiazepines
Correct metabolic acidosis
( NaHCO3 1 – 2 m Eq/kg IV based on arterial ph

13. Maintain urine output
Hydration
Mannitol ( 0.25 g/kg IV )
Furosemide ( 1mg/ kg )
Treatment of arrhythmia ( Xylocaine infusion)
Monitor in ICU

14. REFERENCES
Anaesthesia & co-existing diseases – Stoeltin
g.
Short practice of Anaesthesia – Churchill Dav
idson Problem oriented
Anaesthesia – Stoelting. American Society
of Anaesthesia ( ASA )
Annual refresher lecture notes – 1998. Textbo
ok of Anaesthesia – Ronald Miller.

15. THANKS TO
NANDKISHORE
SIR FOR HIS
GUIDANCE