Correspondence
A patient with severe central core disease
Editor—We report a case of a 19-yr-old primigravida who
was referred to our tertiary obstetric unit at 37 weeks gestation. She was known to have skeletal muscle weakness
since birth and had a history of delayed motor milestones
as a child. Myopathy of an unknown aetiology had been
suspected since early childhood. Additionally, after
sudden cardiac deaths of the patient’s father and brother,
concerns of an underlying familial cardiomyopathy or
rhythm abnormality had been raised.
Our patient had an unremarkable pregnancy with no
clinical history suggestive of cardiovascular disease. On
examination, her height was 148.5 cm with the only positive finding being minimally reduced power involving the
upper arms. There was no contracture or any spinal
deformity. Her gait was normal. Systemic examination
revealed no abnormal findings. ECG and 2D echocardiogram were normal with no evidence of dysrhythmia or cardiomyopathy. An elective Caesarean section at 38 weeks
gestation was planned as our patient had cephalopelvic
disproportion. In view of her history, the operation was
scheduled in the cardiac theatre suite.
Before operation, she received aspiration prophylaxis as
standard. Compound Ringer’s lactate solution was infused
i.v. External defibrillator pads were attached and lateral tilt
and calf compressions used. Radial artery was cannulated.
Regional anaesthesia was induced using a combined spinal–
epidural technique using 2 ml of heavy bupivacaine 0.5%
and fentanyl 20 mg. Caesarean section was uneventful with
300 ml of total blood loss. A healthy baby boy was delivered
weighing 2.8 kg. A rectus abdominus muscle biopsy was
performed and after operation, she was transferred to the
high dependency unit. She made a complete recovery and
was discharged on Day 10. The diagnosis of central core
disease was confirmed on histopathology with biopsy findings suggestive of long standing and severe disease.
Central core disease is a slowly progressive autosomal
dominant congenital myopathy.1 It presents during infancy
with delayed motor milestones secondary to generalized
hypotonia and muscle weakness. It is a histopathological
diagnosis made on finding characteristic central cores on
muscle biopsy. The ‘central core’ is an area of central clearing in the muscle with the loss of myofibrils, mitochondria,
and glycogen. Central core disease has been consistently
associated with malignant hyperthermia (MH).1 Susceptible
patients with central core disease have been shown to have
mis-sense mutation in the ryanodine receptor gene on
chromosome 19. Genetic screening of all patients with
central core disease for MH has been recommended.
Although our patient had an uncomplicated anaesthetic
outcome, she had a high risk of developing MH and avoidance of general anaesthesia probably helped in preventing
this developing. Evidence from the literature would suggest
that any patient with an undefined myopathy that has not
been confirmed by histopathology, genetic mutation analysis, or both is a possible candidate for central core disease
and therefore of developing MH.1 This case highlights the
subtle clinical features with which patients with central core
disease can present. Even in patients with known central
core disease, it is safest to avoid triggering agents like volatile anaesthetics and suxamethonium even if they have a
history of safe anaesthetics in the past,2 as patients with
central core disease may develop MH as a first episode,
despite having no complications on previous general anaesthesia (GA). This susceptibility is thought to depend on the
biochemical milieu at the time of the anaesthetic rather than
an absolute risk with each GA.1 2 Ropivacaine as opposed to
bupivacaine has been shown to have lesser motor block in a
multicentre study in labour.3 It has been reported to be a
safer agent to use in patients susceptible to MH.4 If GA is
needed, we suggest using total i.v. anaesthesia with a vapourfree anaesthetic machine as has been recently reported.5
Anaesthetists need to maintain a high index of suspicion for
risk of developing MH in any patient with an ill-defined
myopathy or non-specific features of muscle disease.
P. V. Waikar*
R. Wadsworth
Manchester, UK
*E-mail: [email protected]
1 Jungbluth H. Central core disease. Orphanet J Rare Dis 2007; 2: 25
2 Treves S, Jungbluth H, Muntoni F, Zorzato F. Congenital muscle disorders with cores: the ryanodine receptor calcium channel paradigm. Curr Opin Pharmacol 2008; 8: 319– 26
3 Halpern SH, Breen TW, Campbell DC, et al. A multicentre, randomized, controlled trial comparing bupivacaine with ropivacaine
for labor analgesia. Anesthesiology 2003; 98: 1431 – 5
4 Osada H, Masuda K, Seki K, Sekiya S. Multi-minicore disease with
susceptibility to malignant hyperthermia in pregnancy. Gynecol
Obstet Invest 2004; 58: 32 – 5
5 Georgiou AP, Gatward J. Emergency anaesthesia in central core
disease. Br J Anaesth 2008; 100: 567.
doi:10.1093/bja/aen198
A LMA CTrachTM for large patients
Editor—The LMA CTrachTM system (CTrach) (The
Laryngeal Mask Company, Singapore) enables viewing of
the glottis, alignment of the laryngeal mask conduit with
the glottis, and tracheal intubation under vision. In earlier
work with the CTrach, it was frequently difficult to view
the glottis, and epiglottic downfolding was the most
common cause.1 This may limit the CTrach’s usefulness
in managing difficult airways and may be a particular
problem in tall obese male patients.2 A CTrach airway
modified for use in big patients may be needed and hence
the size 5L CTrach airway was recently developed.
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Correspondence
The size 5L airway has similar cuff size and tube
curvature as the size 5, but has a 2.2 cm longer tube (outer
curvature length). This enables deeper insertion which
may prevent or aid correction of epiglottic downfolding.
We report our experience with the size 5L CTrach in three
patients whose airways were difficult to manage.
Patient 1 was a 58-yr-old man (1.78 m, 80 kg) having
lumbar spine surgery. He had several missing and loose
teeth. He had a Cormack and Lehane grade 3 larynx on
direct laryngoscopy with both standard and long blade
Macintosh laryngoscopes. We inserted a size 5 CTrach
and achieved ventilation after application of the up-down
manoeuvre. We failed to view the glottis because of
persistent epiglottic downfolding, despite using several
up-down manoeuvres, and removal and reinsertion of the
CTrach. An attempt at tracheal intubation through the
CTrach failed. We then used a CTrach 5L and immediately were able to achieve ventilation. There was still
partial epiglottic downfolding blocking the anterior third
of the glottis, but we easily corrected this by pushing the
CTrach deeper into fully view the glottis. We succeeded in
tracheal intubation at the first attempt.
Patient 2 was a 60-yr-old man (1.82 m 85 kg) having
lumbar spine surgery. He had a receding chin, his teeth
were in very poor condition, and a grade 4 larynx on
direct laryngoscopy. We used a size 5 CTrach and easily
achieved ventilation, but again failed to view the glottis
due to persistent downfolding of the epiglottis. We then
used a size 5L CTrach and immediately obtained a full
view of the glottis and successfully intubated his trachea.
Patient 3 was a 22-yr-old man (1.84 m, 86 kg) having cervical spine surgery. He had marked cervical spinal canal stenosis and we applied manual inline stabilization during all
airway procedures. He had a grade 4 larynx on direct laryngoscopy. With the size 5L CTrach, we were able to achieve
ventilation and a glottis view without the need for any
manoeuvres, and to intubate his trachea at the first attempt.
The concept of CTrach visualization is promising for
difficult airway management and may improve the success
rate of intubation through a laryngeal mask conduit.3
Provided the glottis can be seen, the success of intubation
at the first attempt is very high. The CTrach may be an
efficient device for intubation in morbidly obese patients,
but glottis visualization can be difficult even in experienced hands.4 In two of our patients here, the size 5L
CTrach enabled full glottis views after failure with the size
5. Although our patients were not exceptionally tall and
were not obese, our early experience suggests that the 5L
may meet the need for a suitable CTrach conduit in big
patients with longer oral-pharyngeal-laryngeal distances.
Declaration of interest
The author has no financial relationship with or interests in
the Laryngeal Mask Company or any competing company.
E. H. C. Liu*
Singapore
*E-mail: [email protected]
1 Liu EH, Goy RW, Chen FG. An evaluation of poor LMA CTrach
views with a fibreoptic laryngoscope and the effectiveness of
corrective measures. Br J Anaesth 2006; 97: 878 – 82
2 Cattano D, Pesetti B, Di SC, Giunta F. Evaluation of the LMA
CTrach. Br J Anaesth 2007; 98: 409
3 Liu EH, Goy RW, Lim Y, Chen FG. Success of tracheal intubation
with intubating laryngeal mask airways: a randomized trial of the
LMA Fastrach and LMA CTrach. Anesthesiology 2008; 108: 621– 6
4 Dhonneur G, Ndoko SK, Yavchitz A, et al. Tracheal intubation of
morbidly obese patients: LMA CTrach vs direct laryngoscopy. Br J
Anaesth 2006; 97: 742 – 5
doi:10.1093/bja/aen199
Thrombolysis for massive pulmonary tumour
embolism in a patient with cavoatrial renal
carcinoma
Editor—We would like to report a case in which the
treatment with recombinant tissue plasminogen activator
(rt-PA) appears as a key element of the successful
management of a massive pulmonary tumour embolism in
a patient with renal cell carcinoma (RCC) extending
into the right heart. This catastrophic event has a high
perioperative mortality1 and represents an important challenge for physicians. Few reports of successful surgical
management have appeared,1 and no data are available to
support the efficacy of thrombolytic treatment in this
condition.
A 48-yr-old man, scheduled for surgery for cavoatrial
renal carcinoma, presented with syncope followed by respiratory distress (pH, 7.12; PaO2, 7.3 kPa; PaCO2, 8.9 kPa; 8 litre
min21 of oxygen by face mask) and cardiogenic shock
(arterial blood pressure, 60/40 mm Hg; heart rate, 140 beats
min21). Pulmonary embolism was suspected and the patient
was transferred to the intensive care unit. Initial management
consisted of pressure control ventilation (PEEP 8 cm H2O,
peak airway pressure 28 cm H2O, FIo2 1), fluid loading and
continuous infusion of dobutamine (10 mg kg21 min21) and
norepinephrine (0.6 mg kg21 min21). Despite the therapy,
impairment of gas exchange (pH, 7.29; PaO2, 10.4 kPa;
PaCO2, 4.8 kPa) and haemodynamic instability (arterial
blood pressure, 80/40 mm Hg; heart rate, 155 beats min21)
persisted. An ECG showed tachycardia, right bundle-branch
block, and T-wave inversion in leads V1 – 4. The transthoracic echocardiography showed a dilated right heart, right
ventricular hypokinesis (ejection fraction, 35%), and raised
pulmonary artery systolic pressure (55 mm Hg) (Fig. 1). It
showed the tumour thrombus in the right atrium prolapsing
through the tricuspid valve into the right ventricle during
diastole. Doppler ultrasonography of the lower limbs did not
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