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2939 2 — 30
Diagnostic Challenges in Malignant Hyperthermia
and Anesthesia-Induced Rhabdomyolysis:
A Case Study
ABCDEFG 1 Maya Belitova
BCDF 1 Gergana Georgieva Nikolova
ABCDEF 2 Slavyana Usheva
BCDEFG 1 Maya Todorova Mladenova
BCE 1 Tsvetomir Marinov
CDE 3 Radka Kaneva
ABCDEFG 2 Theophil Sedloev
Corresponding Author: Maya Belitova, e-mail: mbelitova@medfac.mu-sofia.bg
Financial support: The work is a part of “Intensive Care Acquired Muscle Weakness” project under licence grant No. D-322/19.12.2022, funded by
the Medical University of Sofia. The authors received no personal financial support
Conflict of interest: None declared
Patient: Female, 42-year-old
Final Diagnosis: Malignant hyperthermia
Symptoms: Hypercarbia • rhabdomyolysis • masseter spasm
Clinical Procedure: —
Specialty: Anesthesiology • Critical Care Medicine
Objective: Rare disease
Background: Malignant hyperthermia (MH) and anesthesia-induced rhabdomyolysis (AIR) are rare, yet life-threatening com-
plications that need prompt therapeutic actions and logistic preparedness for treatment success. Both condi-
tions are triggered by general anesthetics, particularly volatiles and depolarizing muscle relaxants. In compari-
son with MH, which is an inherited pharmacogenomic disease of calcium channel receptor subpopulation and
arises only after trigger exposure, AIR has been described mostly in patients with muscular dystrophies. In peri-
operative settings, rhabdomyolysis is also observed during propofol infusion syndrome, neuroleptic malignant
syndrome, and cocaine, heroin, and alcohol intoxication. Despite their diverse etiology, the main clinical man-
ifestations of MH and AIR overlap: a hypermetabolic state, hyperpyrexia, hypercarbia, acute renal failure, and
hyperkalemia progressing to cardiac arrest, making the therapeutic approach to the patient extremely difficult.
Case Report: We present an unenviable and challenging clinical scenario of an obligatory general anesthesia with endotra-
cheal intubation in a patient with difficult airways for breast conserving onco-surgery with simultaneous tar-
geted intraoperative 20 Gy irradiation. The case was complicated even further by coincident suspicious clinical
presentation of a mild and self-limited hypercarbia, together with a protracted rhabdomyolysis, without hy-
perpyrexia. Given the atypical and scarce clinical presentation leading to diagnosis uncertainty of MH or AIR,
which was proved only after receiving the genetic results, dantrolene was not administered, and the patient
underwent successful supportive treatment.
Conclusions: The study points to the diagnostic dilemma – crisis event MH or AIR – and raises issues about possible preop-
erative preventive measures and treatment options in patients with an uncertain diagnosis.
Keywords: Dantrolene • Hyperthermia • Rhabdomyolysis • Succinylcholine
Abbreviations: MH – malignant hyperthermia; AIR – anesthesia-related rhabdomyolysis; ETI – endotracheal intubation;
RYR1 – Ryanodine receptor-1; CACNA1S – calcium voltage-gated channel subunit alpha 1 S; STAC3 – SH3
and cysteine-rich domain 3; CK – creatine kinase; TARGIT-IORT – targeted intraoperative radiotherapy
Full-text PDF: https://www.amjcaserep.com/abstract/index/idArt/946306
Authors’ Contribution:
Study Design A
Data Collection B
Statistical Analysis C
Data Interpretation D
Manuscript Preparation E
Literature Search F
Funds Collection G
1 Department of Anesthesiology and Intensive Care, Medical University of Sofia,
University Hospital “Queen Giovanna – ISUL”, Sofia, Bulgaria
2 Department of Surgery, Medical University of Sofia, University Hospital
“Queen Giovanna – ISUL”, Sofia, Bulgaria
3 Molecular Medicine Center, Department of Medical Chemistry and Biochemistry,
Medical University of Sofia, Sofia, Bulgaria
e-ISSN 1941-5923
© Am J Case Rep, 2024; 25: e946306
DOI: 10.12659/AJCR.946306
Publisher’s note: All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated
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APPROVED GALLEY PROOF
Introduction
Malignant hyperthermia (MH) is a rare life-threatening hered-
itary disorder, which represents a hypermetabolic reaction to
currently used halogenated volatile anesthetics and to succi-
nylcholine [1-3]. It is an autosomal dominant disease with main
mutations in RYR1, CACNA1S, and STAC3 genes [3-5] encod-
ing for abnormal ryanodine receptor (RYR) and dysregulated
excitation-contraction coupling in skeletal muscles. Typically,
trigger exposure leads to an unregulated massive passage of
calcium ions from the sarcoplasmic reticulum into the intra-
cellular space, combined with a transient receptor potential-
mediated transsarcolemmal canonical Ca2+ influx. Given the
excessive amount of intracellular calcium, an exaggerated mus-
cle contraction throughout the body musculature (generalized
muscle rigidity) leads to a marked hypermetabolic state with
depletion of energy stores, hyperthermia, hyperkalemia, rhab-
domyolysis, acute renal failure, and profound acidosis [2,6]. In
comparison, anesthesia-induced rhabdomyolysis (AIR) is also
a rare anesthetic complication and represents a rapid break-
down of skeletal muscles, with massive release of sarcoplas-
mic content into the bloodstream: electrolytes and proteins,
notably creatine kinase (CK), lactate dehydrogenase, and po-
tassium [6-9]. Succinylcholine and volatiles are the main AIR
triggers in patients with muscular dystrophies. In perioperative
settings, rhabdomyolysis also arises during propofol infusion
syndrome in otherwise healthy patients after prolonged pro-
pofol administration, despite a potential risk in patients with
mitochondrial myopathy [10]. Non-pharmacological rhabdomy-
olysis could be triggered by physical (trauma, crush-syndrome,
burns, electrocution, seizures, compression, and compartment
syndrome), chemical (toxins, alcohol, carbon monoxide or cy-
anide poisonings, heroin, and cocaine), and biological factors
(hypoxia, infections, polymyositis, dermatomyositis, and thy-
roid disorders) [11]. AIR is presented by a diverse clinical pic-
ture, ranging from life-threatening hyperkalemia, with cardi-
ac arrest, acute renal failure, and compartment syndrome, to
asymptomatically increased CK, electrolyte, and enzyme im-
balances [7,8,12].
Breast cancer is the most common heterogenous oncologi-
cal disease in women worldwide, accounting for more than
2.3 million new cases in 2020, according to the Global Cancer
Observatory database [13]. Targeted intraoperative radiation
therapy (TARGIT-IORT) or delivering a high dose of radiation
therapy to the fresh tumor bed immediately after lumpec-
tomy by a multidisciplinary team of surgeons, anesthesiol-
ogists, radiation oncologists, and physicists during breast-
conserving surgery is a safe and effective technique for early
breast cancer, which is designed to serve as a replacement
for whole breast external beam radiotherapy in low-risk pa-
tients [14,15]. This approach allows for precise irradiation of
tissue where the possibility of remaining vital tumor cells is
highest while sparing nearby vital organs, such as the heart
and lungs. Unfortunately, due to the sophisticated procedure,
there are long waiting lists in most centers worldwide. Giving
new insights on a multifaceted MH picture, treatment options
without dantrolene, and uneventfully performed temperature-
sensitive procedure, the presented case is valuable and unique
for the medical literature.
Case Report
A 42-year-old patient with short neck and obesity (thyromen-
tal distance 6 cm; Mallampati III; body weight of 98 kg; body
mass index of 38.2 kg/m2) received a diagnosis of a 20-mm
tumor mass in the upper outer quadrant of the right breast,
which was defined as low-differentiated invasive ductal can-
cer G3, (estrogenic receptor, negative; progesterone receptor,
negative; human epidermal growth factor receptors 2, 3+/pos-
itive; inhibition constant 67, 80%) by core-needle biopsy. The
patient was a known current heavy smoker, reporting more
than 20 pack-years. The medical record showed that the pa-
tient underwent short general anesthesia in the past for a hys-
teroscopy, with no clear mention of administered anesthetics
or specific events during the procedure. All laboratory test re-
sults were unremarkable, and the patient denied any knowl-
edge of anesthesia-related accidents in relatives in ascending
and descending lines. There were no signs of axillary nodal
involvement, and the patient was referred for a breast-con-
serving surgery with simultaneous TARGIT-IORT with a 20-Gy
cumulative dose.
After routine premedication (10 mg metoclopramide, 40 mg
esomeprazole, and 12 mg dexamethasone) and pre-oxygen-
ation, general anesthesia was induced intravenously (1.5 µg/kg
fentanyl, 2 mg/kg propofol, and 1 mg/kg succinylcholine). Given
the Cormac Lehane Class III-IV grade found during laryngosco-
py, and an unsuccessful attempt for endotracheal intubation
(ETI), the anesthesiologist (fellow with 2 years clinical experi-
ence) called for help and woke the patient up. The consultant
anesthesiologist (30 years clinical experience), who managed
the patient afterward, met a fully awake patient, without any
complaints or pathological symptoms. After a second intrave-
nous induction of 1.5 µg/kg fentanyl, 2 mg/kg propofol, and
1 mg/kg succinylcholine (a time lapse between the first and
the second succinylcholine dose of approximately 5 to 7 min),
limited mouth opening of approximately 2 cm was noted; how-
ever, the patient was successfully and atraumatically intubat-
ed. Thereafter, a balanced general anesthesia was started with
sevoflurane. Mechanical ventilation was instituted with tidal
volumes of 7 mL/kg, respiratory rate 12/min, minute ventilation
80 mL/kg/min, PEEP 5 mmH
2
O, and P
peak
16 mmHg. An end-tid-
al carbon dioxide (ETCO2) of 48 mmHg was noted on a mon-
itor 3 min after ETI. The minute ventilation was increased to
Belitova M. et al:
The diverse face of malignant hyperthermia
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APPROVED GALLEY PROOF
100 mL/kg/min, sevoflurane was discontinued (maximal mini-
mum alveolar concentration achieved was 0.48), and addition-
al 0.3 mg fentanyl was administered intravenously. Due to the
unexpected and, at the time, unclear situation, the surgical
staff were informed to stop the operation. During the next 10
min, ETCO2 rose up to 59 mmHg. At that time, the diagnosis
of MH was suspected, irrespective of the patient’s stable vital
signs: blood pressure 100/60 mmHg; heart rate 78 beats/min,
sinus rhythm; peripheral oxygen saturation 98% at FiO2 33%;
and esophageal, axillary, and tympanic temperature of 37.2°C.
Local MH crisis protocol was started in the following order:
Priority actions: the inhalational anesthetic was already dis-
continued; all operating room staff were informed and mobi-
lized; activated charcoal filters were placed on inspiratory and
expiratory limbs of the breathing circuit; the anesthetic ma-
chine was replaced with a “vapour free” working station; pro-
pofol infusion was started at a rate of 100 µg/kg/min; hyper-
ventilation 120 mL/kg/min was instituted with high fresh gas
flow rate of 12 L/min; FiO
2
was raised to 50%; dantrolene was
ordered and its reconstitution was considered; and laboratory
Parameter (units)
10 Min
after ETI;
FiO2 50%
30 Min
after ETI;
FiO2 50%
40 Min
after ETI;
FiO2 50%
4 h after
ETI –
admission in ICU;
FiO2 50%
24 h after
Intubation;
FiO2 21%
Reference
values
ctHb (mg/dL) – 13.6 13.2 12.3 13.7 11.5-16
PO2 (mmHg) – 257.8 248.0 176.5 99.1 80-100
ETCO2 (mmHg) 59 54.7 35 – – –
PCO2 (mmHg) – 59 37.1 25.1 36.5 35-45
pH – 7.24 7.34 7.46 7.50 7.35-7.45
SatO2– 99.70% 99.80% 99.70% 98.40% 75-99
BE – -5.00 -3.80 -3.60 -0.60 -0 to +3
BB (mmol/L) – 41.71 42.2 43.27 46.85 44-48
HCO3 (mmol/L) – 22.8 21.5 18.1 20.70 21-26
Lactate (mmol/L) – 3.1 1.8 1.65 1.69 <2
Temperature (°C) 37.2 37.2 37.2 37.2 37.2 <37.5
INR 0.99 0.86 0.97 1.02 0.8-1.1
Table 1. Arterial blood gas analysis of a patient with malignant hyperthermia.
FiO2 – fraction of inspired oxygen; ETI – endotracheal intubation; ICU – Intensive Care Unit; ctHb – concentration of total hemoglobin;
PO2 – partial oxygen pressure in arterial blood; PCO2 – partial pressure of carbon dioxide in arterial blood; ETCO2 – level of carbon
dioxide released at the end of an exhaled breath; Sat O2 – oxygen saturation in arterial blood; BE – base excess; BB – total buffer base;
HCO3 – concentration of bicarbonate; lactate – concentration of lactic acid; INR – international normalized ratio.
Parameter
(units)
30 Min.
after ETI
40 Min.
after ETI
4 h after ETI
admission in
ICU; FiO2 50%
24 h after ETI;
FiO2 21%
48 h after ETI;
FiO2 21%
Postoperative
Day 7
Reference
values
Potassium
(mmol/L) 5.1 4.9 3.7 3.5 3.4 3.7 3.5-5.1
Creatine kinase
(U/L) 1579 2713 16 268 >37 000 >37 000 2658 25-170
Creatinine
(umol/L) 102 101 101 68 68 88 40-120
Table 2. Biochemical analysis of the patient with malignant hyperthermia.
FiO2 – fraction of inspired oxygen; ETI – endotracheal intubation.
Belitova M. et al:
The diverse face of malignant hyperthermia
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APPROVED GALLEY PROOF
check was ordered (Tables 1,2). At that point, around 25 min af-
ter intubation, in the face of steadily decreasing ETCO
2
around
50 mmHg and in the absence of pyrexia, the operative proce-
dure proceeded. Its total duration was 3.5 h, including 50 min
irradiation. During the next 10 min, ETCO2 normalized.
Subsequent actions: forced diuresis of 3 mL/kg/h was main-
tained throughout the surgery by additional volume load of
15-20 mL/kg crystalloid solutions and 0.15 mg/kg furosemide,
and serial blood gas analyses (Tables 1, 2) were arranged.
After the operation, the patient was extubated with restored
vital functions and admitted in the Intensive Care Unit with
normal respiration but with an elevated CK level. In the ab-
sence of any complaints and pain, the patient was rehabilitat-
ed to the bedside upright position on the same day. Despite a
maintained forced diuresis (3 mL/kg/h) over the next 3 days,
a mild urine discoloration appeared, and as a preventive mea-
sure against acute renal injury, 2 hemodialysis sessions were
performed due to extremely elevated CK levels, ranging from
1579 U/L at 30 min after intubation to >37 000 U/L at 48 min
postoperatively (Table 2). With the patient in a stable condi-
tion, without alarming signs of organ failure and reporting
only mild muscle weakness, she was transferred to the sur-
gical ward on postoperative day 3 and discharged home on
postoperative day 5 in very good health.
Later, a genetic test was performed, verifying a pathogenic
variant of the RYR1 gene – c.487C>T; p. (Arg163Cys), zygosity,
heterozygous, which is associated with an autosomal reces-
sive form of congenital myopathy, and is a dominantly inherit-
ed predisposition for MH. The patient was advised to arrange
a genetic consultation for her children and relatives.
Discussion
The prevalence of MH is difficult to estimate. The reported
range is about 1 in 50 000 to 100 000 general anesthetic pro-
cedures [1-5]; however, it is usually underestimated, because
not all susceptible patients are exposed to the triggers. In con-
trast, the prevalence of gene mutations encoding the disease
is much higher, ranging from 1 in 2000 to 1 in 3000 in the
general population [5]. Both a genetic predisposition and one
or more triggers are required for the development of an MH
crisis during anesthesia [16]. Over 400 mutations have been
identified in the RYR1 gene located on chromosome 19q13.1,
and at least 65 are causal for MH [4,5,9]. AIR, a breakdown of
muscle fibers, releasing nephrotoxic intracellular contents and
potassium into the systemic circulation, also represents an an-
esthetic crisis, with overlapping triggers and clinical picture.
Volatiles and the depolarizing muscle relaxants are the stron-
gest triggers for both crisis events. A variety of drugs could
induce rhabdomyolysis in the perioperative settings, such as
neuroleptics, antihistamines, corticosteroids, statins, anti-lip-
id drugs, alcohol, and substance abuse drugs (heroin, cocaine)
[7,16]. Among the non-anesthetic causes are thermal or ra-
diation body exposure, intensive physical activity, infection,
emotional stress, caffeine, hyperglycemia, and muscle meta-
bolic dysfunction [8,9,11,14]. Patients with comorbid neuro-
muscular diseases [14] are also at increased risk. The clinical
presentation and classical first signs of MH crisis include an
inexplicable and rapid elevation of ETCO2 >55 mmHg, pyrexia
>38.8°C, masseter spasm, generalized muscle rigidity, tachy-
cardia and dysrhythmia, acidosis, rhabdomyolysis, and acute
renal failure [1-3,7,8,16]. MH is characterized by rapid progres-
sion, and high mortality if unattended or untreated. There are
also observed cases with occurrence of atypical reactions due
to variable penetrance of this autosomal dominant inherited
trait gene (97.3%), such as depression of consciousness and
coma (9.8%), cardiac dysfunction (9.4%), pulmonary edema
(8.4%), disseminated intravascular coagulation (7.2%), and
hepatic dysfunction (5.6%) [9,17]. Since MH and AIR are rare
conditions, only 2 case reports are available in the literature
[18,19] concerning MH in patients with breast cancer, but our
case is unique, raising further issues discussed below that
need to be addressed.
Airway Management of a Patient with Mallampati III
and Obesity with Expected Difficult Airways and General
Anesthetic Choice
Unfortunately, there are not clear guidelines addressing this
patient’s population management. Given the obligatory ETI
for securing the airways, particularly for TARGIT-IORT, during
which all medical staff were outside the operating room for
the irradiation procedure, rocuronium was unavailable, and
there were difficult airways and a first unsuccessful intuba-
tion attempt, the second succinylcholine dose was inevitable.
If a consultant anesthesiologist took the case from the begin-
ning, with proper preparedness, the second induction and, re-
spectively, the second succinylcholine dose could have been
avoided, hence putting the patient, and other similar patients,
at a lower risk of complications. To the best of our knowledge,
this is the first reported case in the literature with MH crisis
after a second full-induction succinylcholine dose, a strong MH
and AIR trigger. Consequently, our general anesthetic choice
was to rule out any AIR or MH trigger. Total intravenous an-
esthesia propofol + fentanyl is a treatment of choice in case
of MH. Additionally, in the perioperative settings, rhabdomy-
olysis could be observed during neuroleptic malignant syn-
drome (thus excluding neuroleptics and antiemetics from the
safe medication list), also during propofol infusion syndrome,
linked to long-term (more than 48 h) and high dosage (above
4.0 mg/kg/h in stretch) propofol administration. Given the
obligatory patient’s motionlessness, especially during 20-Gy
irradiation (55 min), and in the face of diagnosis uncertainty,
Belitova M. et al:
The diverse face of malignant hyperthermia
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APPROVED GALLEY PROOF
it was not recommended to administer any muscle relaxant.
Hence, the medical team chose opiate-based total intrave-
nous anesthesia propofol+fentanyl, with a total fentanyl dose
of 6 µg/kg and low total propofol dose of 3.8 mg/kg/h, with-
out muscle relaxation.
The Dilemma: MH or AIR?
The reported patient had no clear history of MH predisposition,
although upon further questioning, she remembered muscle
weakness after a previous anesthesia. The potential crisis trig-
gers for MH and AIR were the high total succinylcholine dose
(2.0 mg/kg) administered in 5 to 7 min, the sevoflurane (ad-
ministered shortly after ETI at a low minimum alveolar concen-
tration of 0.48 achieved), and the radiation therapy [20]. The
mild hypercarbia and the limited mouth opening during laryn-
goscopy were the first crisis symptoms and corner stones for
suspecting MH, although there is no clear definition of mas-
seter spasm [21]. They could also have been attributed to AIR
or, as happens often in practice, were attributed to the obvi-
ous difficult airways: obesity, short neck, and unequivocal pos-
sibility for hypoventilation during the 2 anesthesia induction
attempts. Hypercarbia was mild, self-limited, and lasted only
35 min in total. It would be extremely helpful to have the clear
definition of masseter spasm or at least a record on the pre-
operative report of the interincisor gap in centimeters in every
patient with planned general anesthesia and ETI. The picture
of our patient became more complicated with the absence of
pyrexia, hyperkalemia, lack of muscle rigidity signs throughout
the body musculature, and hemodynamic stability maintained
during the entire intra- and postoperative period, coupled with
self-limited hyperlactatemia. All temperature measurements
showed 37.2°C throughout the total hospital stay; later, the
patient mentioned that this was her normal body tempera-
ture. Proving an AIR diagnosis is a time-dependent process,
in which approximately 72 h are needed for CK and other en-
zymes’ maximal elevation [12]. Consequently, in atypical cas-
es, because of the requirement of prompt treatment, the bet
-
ter approach is to accept the MH diagnosis. Furthermore, the
treatment of choice in MH is dantrolene, as opposed to anti-
hyperkalemia treatment in cases with AIR [22]. Also, routine
temperature measurement is not an obligatory part of the pre-
operative check-up. It is our opinion that this should be an
indispensable part of preoperative check-up procedures, es-
pecially in those that change the body temperature, like irra-
diation or thermoablation.
Treatment
Because of the atypical, scarce, and obscured clinical presenta-
tion of our patient, 10 min after ETI (maximal ETCO
2
59 mmHg,
with upper normal limit minute ventilation of 100 mL/kg/min),
we needed to switch the local MH crisis protocol on. Priority
actions were implemented in the next 10 min. Intraoperative
evaluation according to the Clinical Grading Scale for MH at 10
min revealed a score of 30 points (masseter spasm, 15 points;
hypercarbia, 15 points), representing MH likelihood grade 4,
“somewhat greater than likely” [23]. At 30 min, the MH clini-
cal grading scale would have been 40, considering arterial pH
<7.25 is 10 points; however, hypercarbia had already started to
fall, and the values were below the limits. Although our med-
ical facility stocks dantrolene, which is the etiologic mainstay
of treatment [24-28], the typical time for reconstitution of an
initial dose of 2.5 mg/kg (250 mg or 12.5 vials 20 mg each)
would be 90 s per vial, or more than 20 min in total. During
the next 10 min, ETCO
2
normalized; hence, dantrolene admin-
istration was withheld, and we administered a symptomatic
rather than etiologic treatment with dantrolene [27-29]. Clear
protocols with clear dantrolene administration guidelines are
needed for treatment of atypical MH cases like ours. Whether
dantrolene could have been applied with the aim to limit rhab-
domyolysis remains a question for future consideration, pro-
vided the FDA has approved dantrolene only for MH treatment.
Moreover, the FDA has warned about its carcinogenesis and
mutagenesis [30], especially in breast cancer cases. Given the
patient’s stable vital signs, the operative procedure was not
cancelled, and we decided to proceed with the surgical inter-
vention, allowing the delivery of a single dose of 20 Gy in the
tumor bed, using the Intrabeam System PRS 500 with XRS 4
Zeiss, thus extending the surgical procedure by 55 min. The ad-
vantages of TARGIT-IORT are indisputable and proven by mul-
ticentric studies from leading centers worldwide in respect to
simultaneous application during surgery (1-step procedure), re-
duced irradiation of normal tissues, economic viability, better
cosmetic outcomes, preferred choice by patients and special-
ists, and improved quality of life. A recent analysis estimates
that at least 44 752 patients with breast cancer were treated
with TARGIT-IORT in 260 centers in 35 countries, saving >20
million miles of travel and preventing about 2000 non-breast
cancer deaths [13-15]. On the other hand, receiving a 20-Gy
radiation dose at once is not indifferent to the organism, as
the treatment targeted area temperature increases above
0.89±1.96°C during conventional external beam radiotherapy
[20]. To alleviate the risk for developing next episodes of MH
during the numerous courses of standard external beam ra-
diotherapy in the irradiation department, we preferred to de-
liver radiation intraoperatively under constant monitoring. To
the best of our knowledge, this is the first MH case success-
fully treated without dantrolene after a high total succinyl-
choline dose and uneventful intraoperative radiation therapy.
Obviously, our patient developed rhabdomyolysis, proven by
high CK levels [12]. Whether this rhabdomyolysis was aggra-
vated by irradiation, and whether dantrolene administration
at any time after ETCO2 normalization could have prevented
rhabdomyolysis are questions that need to be addressed fur-
ther. Two hemodialysis sessions were administered to prevent
Belitova M. et al:
The diverse face of malignant hyperthermia
© Am J Case Rep, 2024; 25: e946306
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APPROVED GALLEY PROOF
further potential complications and acute renal injury [2,7,8].
Thanks to comprehensive care and monitoring of the patient’s
vital parameters throughout the whole procedure, our team
was able to deliver IORT successfully during breast-conserv-
ing surgery to a patient with MH.
Conclusions
MH and AIR are rare intraoperative life-threatening anesthet-
ic-induced reactions, with high rates of morbidity and mor-
tality. Since MH exhibits highly variable clinical symptoms, in
cases of obscure diagnostic dilemma MH or AIR, it is better to
start MH crisis event treatment instead of waiting for diag-
nosis confirmation. To reduce misdiagnosis chances, it is our
recommendation to record the patient’s body temperature
and interincisor distance in centimeters during the preopera-
tive check-up if general anesthesia or a body temperature-af-
fecting procedure is planned. Also, patients with difficult ETI
signs and obligatory ETI should be treated by highly experi-
enced anesthesiologists to avoid unnecessary risks related to
the second induction and second potential trigger medication.
Ethic Statement
All procedures performed in this study were in accordance
with the ethical standards of the institutional and/or nation-
al research committee(s) and with the Helsinki Declaration (as
revised in 2013). Written informed consent for publication of
this case report was obtained from the patient.
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The diverse face of malignant hyperthermia
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