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46 Cards in this Set
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[May09] Features of eaton lambert include all EXCEPT...
a) Associated with SCLC b) improvement with exercise c) defect in ACh release from motor end plate d) dry mouth e) Fatigue with exercise |
e) Fatigue with exercise
- From UTD a) Associated with SCLC - 'Although Lambert-Eaton myasthenic syndrome can occur at any point in the course of SCLC, it may serve as a marker for early disease.' b) improvement with exercise - 'Maximal isometric contraction of the relevant muscle for 10-15 seconds can sometimes lead to temporary reappearance of previously depressed or absent deep tendon reflexes, and to temporary improvement of muscle weakness.' c) defect in ACh release from motor end plate - 'Antibodies directed against the voltage-gated calcium channel (VGCC), a large transmembrane protein with multiple subunits, play a central role in the pathophysiology of LEMS. These antibodies INTERFERE WITH THE NORMAL CALCIUM FLUX REQUIRED FOR THE RELEASE OF ACETYCHOLINE.' d) dry mouth - 'Autonomic dysfunction is often present and can be an important clue to the diagnosis. Dry mouth from reduced salivation is the most common autonomic symptom and occasionally is the presenting complaint, while erectile dysfunction is a common in men with LEMS.' e) Fatigue with exercise - answer by exclusion. ----------- |
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AA51
Features of Eaton-Lambert Syndrome include all EXCEPT? A. Associated with small cell lung cancer B. Defect in ACh release from the motor end plate C. Dry mouth D. Fatigue with exercise |
D. Fatigue with exercise
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AM04C ANZCA Version [Jul06] Q45
A 7 year old 30 kg. boy was booked for repair of an inguinal hernia. He was noted to have muscular looking arms and legs. Following midazolam premedication anaesthesia was induced with thiopentone intravenously and N2O/O2 by mask. Airway difficulties led to his being given 30 mg of suxamethonium. He showed vigorous fasiculation followed by generalised muscular rigidity. The rigidity persisted despite another 30 mg. of suxamethonium intravenously. The probable cause of this response to suxamethonium is A. atypical pseudocholinesterase B. Duchenne's muscular dystrophy C. familial periodic paralysis D. hyperkalaemia E. myotonia congenita |
E. Myotonia congenita
-- B. Duchenne's muscular dystrophy - false: The diagnosis should have been made by the age of seven. "The disease is caused by an X-linked recessive gene and becomes apparent in 2- to 5-year-old boys. Initial symptoms include a waddling gait, frequent falling, and difficulty climbing stairs, and these reflect involvement of the proximal skeletal muscle groups of the pelvic girdle. Affected muscles become larger as a result of fatty infiltration, and this accounts for the designation of this disorder as pseudohypertrophic. There is progressive deterioration in skeletal muscle strength, and typically these boys are confined to a wheelchair by age 8 to 10." (Stoelting) E. myotonia congenita - true "Myotonia congenita is transmitted as an autosomal dominant trait and becomes manifest at birth or during early childhood. Skeletal muscle involvement is widespread, but there is not usually involvement of other organ systems. Muscle hypertrophy and myotonia are present. The disease does not progress nor does it result in a decreased life expectancy. Patients with myotonia congenita respond to phenytoin, mexiletine, or quinine therapy. The response to succinylcholine administration is abnormal." ----------- |
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AM06 ANZCA version [2003-Apr]
In patients with hypokalaemic periodic paralysis one should avoid A. anxiolytic drugs B. beta-adrenergic antagonists C. intravenous dextrose D. regional anaesthesia E. suxamethonium |
C. intravenous dextrose
General guidelines for perioperative care include close control of plasma potassium concentration, avoidance of large glucose and salt loads, carbohydrate-poor diet, maintenance of body temperature and acid-base balance, and careful use of neuromuscular blocking agents with continuous monitoring of neuromuscular function. ----------- |
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AM07
The peri-operative management of a patient prone to hypokalaemic periodic paralysis should include A. a reduced carbohydrate intake in the pre-operative twenty four hours B. ready availability of intravenous acetazolamide C. avoidance of intravenous sodium loads D. the use of moderate intra-operative hyperventilation |
A. a reduced carbohydrate intake in the pre-operative twenty four hours
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AM09b
Features & management of the malignant neuroleptic syndrome do NOT include: A. Genetically determined response to dopamine antagonists B. Treatment with dantrolene C. Hyperthermia, tachycardia & peripheral vasoconstriction D. Raised white cell count E. Hyperthermia not often seen |
E. Hyperthermia not often seen
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AM09c ANZCA Version [Jul06][Apr07]
In the Neuroleptic malignant syndrome A. there is a familial incidence B. non depolarizing muscle relaxants decrease the muscle rigidity C. creatinine kinase levels are elevated following an episode D. there is an association with malignant hyperpyrexia E. hyperthermia does not always occur |
B. non depolarizing muscle relaxants decrease the muscle rigidity
A. true ----------- |
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AM09d
Regarding NMS, which is incorrect: A. a rare event due to dopaminergic antagonist B. successfully treated by bromocriptine C. successfully treated by dantrolene D. unlike MH, NMS does not have a genetic component E. extrapyramidal signs, hyperthermia, peripheral vasoconstriction, and autonomic features |
D. unlike MH, NMS does not have a genetic component
- "Familial clusters of NMS suggest a genetic predisposition to the disorder [30]. Genetic studies have shown that the presence of a specific allele of the dopamine D2 receptor gene is over represented in NMS patients [31]. This allele is associated with reduced density and function of dopamine receptors as well as decreased dopaminergic activity and metabolism." (Uptodate) However note this:"there is no familial pattern or evidence of inheritance in neuroleptic malignant syndrome" (Stoelting's A and CED Ch22) ----------- |
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AM09e ANZCA version [Apr08] [Mar12-Q122][Aug12]
The diagnosis of neuroleptic malignant syndrome requires the presence of: A. Diaphoresis B. elevated plasma creatinine kinase (some recalled just ↑ CK) C. hypertension D. muscle rigidity E. tachycardia |
D. Muscle rigidity
and possibly B. ↑ CK if CK = creatine kinase NOT creatinine kinase (only using Levenson's crier for dx of NMS) -- DSM IV-TR criteria: Severe muscle rigidity and elevated temperature associated with use of neuroleptic medication as well as two or more of the following - - diaphoresis - dysphagia - tremor - incontinence - changes in level of consciousness ranging from confusion to coma - mutism - tachycardia - elevated or labile BP - leukocytosis - laboratory evidence of muscle injury Levenson's criteria (3 major, or 2 major and 4 minor criteria are needed for dx) Major criteria - fever - rigidity - elevated creatine kinase (CK) Minor criteria - tachycardia - abnormal BP - altered consciousness - diaphoresis - leukocytosis ----------- |
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AM16 [Mar90] [Mar91] [Mar92] [Apr98] [Apr08] [Oct08] [Aug10]
Dystrophia myotonia is associated with A. Diabetes Mellitus B. Decreased intestinal motility C. Cardiomyopathy D. Ovarian dysfunction E. All of the above |
E. All of the above
- from wiki: A. development of diabetes mellitus - true: "Myotonia dystrophica usually manifests as facial weakness (expressionless facies), wasting and weakness of the sternocleidomastoid muscles, ptosis, dysarthria, dysphagia, and inability to relax the handgrip (myotonia). Other characteristic features include the triad of mental retardation, frontal baldness, and cataracts. Endocrine gland involvement may be indicated by gonadal atrophy, diabetes mellitus, hypothyroidism, and adrenal insufficiency." (Stoelting) B. abnormal intestinal motility - true: "Delayed gastric emptying and intestinal pseudo-obstruction may be present." (Stoetling) C. cardiomyopathy - true: "Death from pneumonia or heart failure often occurs by the sixth decade of life. This reflects progressive involvement of skeletal muscle, cardiac muscle, and smooth muscle. Perioperative morbidity and mortality rates are high due principally to cardiopulmonary complications." (Stoelting) D. ovarian dysfunction - true: See comment on gonadal atrophy in A E. all of the above - best answer ----------- |
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AM17
Myotonic dystrophy A. Usually presents before puberty B. Is frequently associated with cardiac failure C. Is associated with obstructive lung disease D. Contractions are not relieved by NDMR or deep anaesthesia E. Is associated with MV prolapse in >50% of patients |
D. Contractions are not relieved by NDMR or deep anaesthesia
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AM21
The preferred technique of anaesthesia for reduction of a fractured wrist in a patient with myotonic disorder A. general anaesthesia with spontaneous ventilation using a volatile agent B. general anaesthesia with suxamethonium-induced muscle relaxation C. general anaesthesia with a non-depolarising relaxant reversed by neostigmine D. intravenous regional anaesthesia with lignocaine E. axillary brachial plexus block with lignocaine |
D. intravenous regional anaesthesia with lignocaine
- see wiki debate. ----------- |
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AM23
To relieve myotonia: A. Inject procaine into muscle B. Neostigmine C. Isoflurane D. Propofol |
A. Inject procaine into muscle
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AM25 [Apr08] [Oct08] [Sep11] [?Aug12]
In an acute malignant hyperthermia episode A. the serum creatine kinase level peaks within one hour B. the peak serum creatinine kinase level is a good indicator of the amount of muscle involved C. elevated creatine kinase levels contribute to acute renal failure D. the serum myoglobin level does NOT peak for at LEAST 24 hours E. muscle rigidity occurs in 75% of cases |
E. muscle rigidity occurs in 75% of cases
-- A - FALSE creatine kinase peaks around 24 Hrs? B - FALSE peak serum CK is not a reliable indicator of MH vs non-MH, as CK levels of MH patients often within levels expected from surgery itself..."patients who have had an acute MH episode during a surgical procedure may have peak CK values within the range of CK values expected from the procedure itself"...Creatine kinase alterations after acute malignant hyperthermia episodes and common surgical procedures, JF Antognini, Anesth Analg 1995 (81) 1039-42 A&A article...drstitch Serum myoglobin (by radioimmunoassay) and creatine kinase were measured for up to 7 days in 30 patients following surgical procedures, including total hip replacement and bilateral subcostal abdominal incisions. Serum myoglobin reached a maximum of 1390 µg litre–1 (median 345 µg litre–1 for major surgery patients) on the first postoperative day but levels were still elevated by day 7 in some patients. Creatine kinase reached a maximum of 1339 i.u. litre–1 at day 2 (median 422 i.u. litre–1 for major surgery patients), generally peaking 1 day after myoglobin in individual patients. These values may have significance when investigating a suspicion of coincident perioperative events such as myocardial infarction or malignant hyperthermia...Serum myoglobin and creatine kinase following surgery, A. S. Laurence, British Journal of Anaesthesia, 2000; Vol. 84, No. 6 763-766 C - FALSE Myoglobin D - FALSE myoglobin peaks ~ 6hrs later E - TRUE rigidity 80% ----------- |
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AM28a ANZCA version [2002-Mar] Q35, [2002-Aug] Q24 (Similar question reported in [Apr98] [Jul98] [Apr99] [Aug99])
In a patient with myasthenia gravis undergoing a laparotomy for large bowel obstruction, the need for post-operative ventilation is significantly increased by a A. daily dose of pyridostigmine > 450mg B. known history of resistance to suxamethonium C. past history of prednisolone treatment > 10 mg.day-1 D. recent history of dysphagia E. past history of thymectomy |
D. recent history of dysphagia
Predictors of post-operative ventilation in Myasethenia Gravis: • disease duration of more than 6 years • concomitant pulmonary disease • a vital capacity < 40 mL/kg (<2.9L) • pyridostigmine dose > 750 mg/d in association with significant bulbar weakness Note: The studies where these predictors were evaluated were for thymectomy. ----------- |
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AM28b ANZCA version [2003-Apr] Q136, [2004-Aug] Q30, [2005-Apr] [Apr07]Q27
In a patient with myasthenia gravis undergoing a laparotomy for large bowel obstruction, the need for post-operative ventilation is significantly increased by a A. daily dose of pyridostigmine > 180mg B. known history of resistance to suxamethonium C. known history of sensitivity to non-depolarising muscle relaxants D. past history of prednisolone treatment > 10 mg.day-1 E. recent history of dysphagia |
E. recent history of dysphagia
Predictors of post-operative ventilation in Myasethenia Gravis: • disease duration of more than 6 years • concomitant pulmonary disease • a vital capacity < 40 mL/kg (<2.9L) • pyridostigmine dose > 750 mg/d in association with significant bulbar weakness Note: The studies where these predictors were evaluated were for thymectomy. ----------- |
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AM28c [Mar06] [Jul06] [Apr07] [Mar10] [Aug10] Q136
In patients with myasthenia gravis, features which increase the risk of requiring prolonged postoperative ventilation, include each of the following EXCEPT A. a high dose of pyridostigmine preoperatively B. a long history of the disease C. high sensitivity to neuromuscular blocking agents D. history of a previous respiratory crisis E. presence of a bulbar palsy |
C. high sensitivity to neuromuscular blocking agents
- See wiki discussion. Predictors of post-operative ventilation in Myasethenia Gravis: • disease duration of more than 6 years • concomitant pulmonary disease • a vital capacity < 40 mL/kg • pyridostigmine dose > 750 mg/d (?in association with significant bulbar weakness) Note: The studies where these predictors were evaluated were for thymectomy. ----------- |
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AM30 [Oct09]
What disease is MOST likely related to malignant hyperthermia? A. Central core disease B. Duchenne muscular dystrophy C. Eaton-Lambert syndrome D. Familial periodic paralysis E. Facial scapula humoral dystrophy F. Nemaline rod disease G. Myaesthenia gravis |
A. Central core disease
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AM31
Malignant hyperpyrexia A. may be confirmed by a muscle biopsy showing contracture in response to halothane, caffeine and calcium B. is an autosomal recessive disorder C. should be treated with an initial dose of dantrolene of 2.5 mg/kg D. had a mortality as high as 50% prior to dantrolene E. is consistently associated with a rapidly rising temperature as one of the early signs |
C. should be treated with an initial dose of dantrolene of 2.5 mg/kg
- A – calcium not used. Halothane, Caffeine, Ryanodine and Chlorocresol are used B – variable. most common is autosomal dominant C – true (OHB says 1mg/kg but other sources say 2.5mg/kg) D – was higher, about 70% E – temperature is a late sign, and may not always be present ----------- |
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AM32 [Apr99]
In comparing the serotonergic syndrome with the neuroleptic malignant syndrome: 1. Abnormal ocular signs with serotonin but not NMS 2. Muscular rigidity of the lower limbs different to that seen in NMS 3. Can be triggered by dopamine agents unlike NMS which can be triggered by dopamine antagonists like bromocriptine 4. More rapid onset & shorter duration with serotonin syndrome |
2. Muscular rigidity of the lower limbs different to that seen in NMS
4. More rapid onset & shorter duration with serotonin syndrome - “Differentiation of Serotonin Syndrome from NMS is important because: 1. Dantrolene is useful in NMS but not Serotonin Syndrome 2. Chlorpromazine can be used in Serotonin Syndrome but is contraindicated in NMS Distinguishing features which support NMS over SS are: • onset and resolution over days to weeks • Hypersalivation, fever, utism, incontinence more common • Rigidity is lead pipe rather than myoclonic • confusion, hyperreflexia, myoclonus are uncommon in NMS • leukocytosis, rhabdo, acidaemia and raised LFTs are more common in NMS 1 – false, both have abnormal eye signs 2 – true: lead pipe in NMS, myoclonic in SS 3 – false, bromocriptine is a treatment of NMS 4 – true, NMS is days to weeks for onset and resolution. Serotonergic syndrome differentiated by: mydriasis, hyperreflexia, tremors, myoclonus, and diarrhoea. ----------- |
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AM33 [2001-Apr ] MCQ-130
Neuroleptic Malignant Syndrome may be precipitated or exacerbated by 1. metoclopramide 2. droperidol 3. thioxanthenes 4. bromocriptine |
1. metoclopramide
2. droperidol 3. thioxanthenes • all are dopamine antagonists • thioxanthenes - eg. flupenthixol • bromocriptine is a dopamine agonist ----------- From Miller 6th edn p1183 NMS is an uncommon condition caused by central effects of drugs with dopamine antagonist properties, including antipsychotics (e.g., haloperidol), and by drugs used for sedation or as antiemetics (e.g., Compazine, metoclopramide, droperidol) |
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AM34
Myotonia: A. Reversed with neuromuscular blockade B. Autosomal dominant appearing 2nd-3rd decade C. Not reversed with deep inhalational anaesthesia D. Not reversed with regional anaesthesia E. Give volatiles & NM blockers to help contractures |
D. Not reversed with regional anaesthesia
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AM35
Myotonia dystrophica 1. is associated with cataracts 2. is strongly associated with malignant hyperpyrexia 3. can result in increased sensitivity to respiratory depressants 4. has its inheritance best described as autosomal recessive |
1. is associated with cataracts
3. can result in increased sensitivity to respiratory depressants - see wiki ----------- |
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AM36 [2001-Sep ] MCQ-134.
Therapies that have been reported to be useful in the management of Neuroleptic Malignant Syndrome include A. dantrolene B. bromocriptine C. levodopa D. amantadine |
All of the above
Neuroleptic malignant syndrome (NMS) is a relatively rare but potentially fatal complication of the use of neuroleptic drugs. A wide variety of antipsychotic agents is associated with this syndrome, including phenothiazines, butyrophenones, thioxanthenes, benzamides and miscellaneous novel antipsychotic agents such as clozapine and risperidone. Two theories to explain NMS: (1) a neuroleptic-induced alteration of central neuroregulatory mechanisms (via central dopamine blockade in hypothalamus) (2) an abnormal reaction of predisposed skeletal muscle (similar to MH) Diagnosis of NMS • Major - Fever, rigidity, elevated creatine phosphokinase concentration • Minor - Tachycardia, abnormal arterial pressure, tachypnoea, altered consciousness, diaphoresis, leucocytosis Successful treatment of NMS depends on early clinical recognition and prompt withdrawal of the neuroleptic agents. General symptomatic treatment, such as hydration, nutrition and reduction of fever, is essential. Secondary complications, such as hypoxia, acidosis and renal failure, must be treated aggressively. • dantrolene -> treat muscle rigidity • bromocriptine / levodopa / amantadine are all dopamine agonists British Journal of Anaesthesia, 2000, Vol. 85, No. 1 129-135 ----------- |
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AM37
The caffeine-halothane contracture test for malignant hyperthermia 1. may be performed up to 24 hours following collection of the specimen 2. has a 10 - 20% false positive rate 3. is indicated in patients with neurolept malignant syndrome 4. requires that the muscle specimen has NOT been directly infiltrated with local anaesthetic |
4. requires that the muscle specimen has NOT been directly infiltrated with local anaesthetic
and maybe 2. (see below) - 1. may be performed up to 24 hours following collection of the specimen - false. From 'Testing for Malignant Hyperthermia' nesthesiology, V 96, No 1, Jan 2002: "The test must be completed within approximately 5 h after muscle harvest". 2. has a 10 - 20% false positive rate - ?Maybe true: from ref in 1. "Currently, the North American and European tests are 97–99% sensitive (i.e., 1–3% false negatives). This sacri- fices specificity, so that 10–15% of normal patients will have false-positive tests.12 The specificity of the Euro- pean protocol (~90%) is greater than that of the North American protocol (~80–85%)." However 2005 Blue book: "Results estimate that the (EMHG) IVCT has at least 99% sensitivity and 94% specificity. It should be emphasized that the EMHG IVCT thresholds have been deliberately set to reduce the clinically dangerous result of a false negative. " 3. false 4. TRUE! "Direct muscle infiltration with local anesthetic is contraindicated because it could adversely affect tissue viability." From ref in 1. ----------- |
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AM38 [Oct08]
The earliest sign in the development of malignant hyperthermia is A. acidosis B. hyperthermia C. increased end-tidal carbon dioxide concentration D. muscle rigidity E. myoglobinuria |
C. increased end-tidal carbon dioxide concentration
-- From Yao Ch53 Specific clinical features for MH - Increase in end-tidal CO2 during constant ventilation (the most sensitive and specific sign) - Generized rigidity (extremely high specificity) - Masseter Muscle Rigidity (MMR) - Increased temperature (not uncommonly higher than 40 degC) Nonspecific - TACHYCARDIA (earliest and most consistent clinical sign however not specific) - Tachypnoea - Arrhythmias - Skin Mottling - Profuse sweating - Altered BP ----------- |
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AM39
Features of Guillain-Barre syndrome include: A. distal loss of sensation B. extensor plantar responses C. facial weakness D. proximal weakness greater than distal weakness E. pseudobulbar palsy |
C. facial weakness
- GUILLAIN-BARRE SYNDROME Rapidly Progressive demyelinating illness Steroids not helpful Autonomic Dysfunction important Protein in CSF Supportive therapy, maybe plasmpheresis or gammaglobulin 85% will recover Mortality is 3-8% CLINICAL FEATURES — Two-thirds of patients develop the neurologic symptoms two to four weeks after what appears to be a benign respiratory or gastrointestinal infection [1,4]. The initial symptoms of AIDP are fine paresthesias in the toes and fingertips, followed by lower extremity weakness that may ascend over hours to days to involve the arms, cranial nerves, and (in severe cases) the muscles of respiration. Early in the course, patients frequently complain of aching or sciatica-like lower back or leg pain [30,31]. In contrast, the Miller Fisher syndrome primarily affects the cranial nerves. Unpredictable rapid (within hours) deterioration in respiratory capacity and progression of muscle weakness can occur in some patients. More than 90 percent of patients reach the nadir of their function within two to four weeks after the onset of symptoms [32], with return of function occurring slowly over weeks to months. At some point during their illness, up to 25 percent of patients require mechanical ventilation [33]. A chronic (extending beyond two months), slowly progressive or relapsing inflammatory demyelinating polyneuropathy is generally considered a distinct entity from acute GBS. (See "Overview of polyneuropathy" and see "Differential diagnosis of peripheral nerve and muscle disease"). Physical examination — Physical examination reveals symmetric weakness with diminished or absent reflexes. There is minimal loss of sensation despite paresthesias. Signs of autonomic dysfunction are present in 50 percent of patients, including [34]: • A variety of cardiac dysrhythmias (asystole, bradycardia, persistent sinus tachycardia, and atrial and ventricular tachyarrhythmias) • Orthostatic hypotension • Transient or persistent hypertension • Paralytic ileus Bladder dysfunction Abnormal sweating DIAGNOSTIC STUDIES — Electrodiagnostic studies are the most specific and sensitive tests for diagnosis of the disease. They demonstrate a variety of abnormalities indicating evolving multifocal demyelination, including [35,36]. (See "Clinical neurophysiology"). • Slowed nerve conduction velocities • Partial motor conduction block • Abnormal temporal dispersion • Prolonged distal latencies ----------- |
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AM40 ANZCA version [2001-Apr] Q125
In testing for malignant hyperthermia susceptibility 1. an increase in contracture to either halothane or caffeine (during in vitro testing) is considered a positive result. 2. defects in the RYR1 gene account for a major proportion of cases 3. the false positive rate for in vitro testing is approximately six percent 4. genetic testing can now be used to replace in vitro contracture testing |
1,3 and maybe 2?
- 1 – truish, but need to do both. if only one is positive, it is considered equivocal in Europe, but “susceptible” by Denborough 2 – Denborogh says only about 20% are ryanodine receptor abnormalities: Black Bank says 85% are RYR1 – quotes Blue Book article 2005 which quotes a year 2000 article which says 85% could be RYR1 if IVCT testing was better. See AM03 above for more. 3 – true, OHB says 93.6% specificity 4 – false. CEACCP article says it is available for certain genes only, but IVCT is still gold standard as many genetic defects still not identified ----------- |
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AM41 ANZCA version [2004-Aug] Q15, [Mar06] Q11, [Jul07][Mar10][Sep11][?Aug12]
The most frequently reported clinical sign in malignant hyperpyrexia is A. arrhythmia B. cyanosis C. sweating D. tachycardia E. rigidity |
A. Tachycardia
-- From Yao Ch53 Specific clinical features for MH - Increase in end-tidal CO2 during constant ventilation (the most sensitive and specific sign) - Generized rigidity (extremely high specificity) - Masseter Muscle Rigidity (MMR) - Increased temperature (not uncommonly higher than 40 degC) Nonspecific - TACHYCARDIA (earliest and most consistent clinical sign however not specific) - Tachypnoea - Arrhythmias - Skin Mottling - Profuse sweating - Altered BP ----------- |
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AM42
In patients with Myasthenia Gravis A. Aminoglycosides have no effect on skeletal muscle weakness B. Corticosteroids are useful as first line therapy C. Myocarditis can result in heart block D. Regular plasmapharesis produces long term benefits E. Thyroid function is not altered |
C. Myocarditis can result in heart block
- A: False Aminoglycosides DO cause aggravated skeletal muscle weakness (UTD). Aminoglycoside-related postoperative respiratory depression caused the greatest frequency of drug-induced neuromuscular blockade. B: False Anticholinesterases (eg. pyridostigmine) are first line C: True Myocarditis can result in AF, heart block or cardiomyopathy D: False Used in crisis or to prepare patient for theatre Plasmapheresis can be used as reserved therapy, and is often instituted in patients who have disease progression that is unresponsive to steroids. From UTD: Bridge therapy — For those patients with MG in whom it is especially desirable to avoid glucocorticoids (such as those with poorly controlled diabetes) or for those who are not successfully weaned to lower doses of prednisone, we often use monthly courses of IVIG until the more slowly acting immunotherapy takes effect. Monthly plasmapheresis is an alternative to IVIG. However, venous access problems develop with frequent use of plasmapheresis, making it less practical than IVIG for use as a bridge therapy. E: False As an associated auto-immune disease...hyperthyroidism is present in approx 10 % ----------- |
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AM43 ANZCA version [2004-Aug] Q119, [2005-Apr] Q82, [Jul07]
A 13-year-old boy with Duchenne's muscular dystrophy A. is at increased risk of malignant hyperthermia B. is likely to have significant scoliosis C. is more likely to be cachectic than obese D. is unlikely to have cardiac involvement E. may develop rhabdomyolysis when non-depolarising muscle relaxants are used |
B. Is likely to have significant scoliosis
- A. is at increased risk of malignant hyperthermia - controversial and not the best answer: "The lack of evidence to support an association between DMD or BMD and MH has led to the proposal of an alternative mechanism termed 'anesthesia-induced rhabdomyolysis' (AIR) (27,44,45). The concept of AIR has been discussed in the literature since 1985, recognizing that rhabdomyolysis not associated with MH can occur in DMD patients after exposure to potent inhalational agents and/or the administration of succinylcholine (10,20,27,36,39,45,46). The supporting evidence for AIR is the same as that against MH: the reactions are atypical for MH despite some similar characteristics, and most caffeine–halothane contracture test results are negative, and probably unreliable, in muscular dystrophy patients. There is also indirect evidence that supports the notion that the lack of dystrophin is the root cause of rhabdomyolysis after exposure to inhalational anesthetic agents." (Hayes et al, Duchenne muscular dystrophy: an old anesthesia problem revisited, in Pediatric Anesthesia Volume 18, Issue 2, Pages 100-106) B. is likely to have significant scoliosis - true: "A progressive scoliosis develops in nearly all children with DMD [39-42]. Scoliosis, in combination with progressive weakness, results in impaired pulmonary function. With progressive disease, patients may eventually suffer acute respiratory failure... Wheelchair-bound children in particular tend to have evidence of scoliosis with poor pulmonary function." (Uptodate) C. is more likely to be cachectic than obese D. is unlikely to have cardiac involvement - false: "DMD causes a primary dilated cardiomyopathy (DCM) and conduction abnormalities, especially intraatrial and interatrial but also involving the AV node, and a variety of arrhythmias, primarily supraventricular [30]. The cardiomyopathy is characterized by extensive fibrosis of the posterobasal left ventricular wall, resulting in the characteristic electrocardiographic changes of tall right precordial R waves with an increased R/S ratio and deep Q waves in leads I, aVL, and V5-6 (figure 2) [31]. As the disease progresses, fibrosis can spread to the lateral free wall of the left ventricle. Significant mitral regurgitation is often present due to involvement of the posterior papillary muscle" (Uptodate) E. may develop rhabdomyolysis when non-depolarising muscle relaxants are used - false: rhabdomyolysis develops with depolarising muscle relaxing agent ----------- |
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AM44
Which of the following blood gases is consistent with an episode of malignant hyperthermia? A. pH 7.13 pCO2 55 HCO3 18 BE -9.1 B. pH 7.34 pCO2 34 HCO3 20 BE 0 C. pH 7.22 pCO2 44 HCO3 19 BE -2.3 D. pH 7.46 pCO2 34 HCO3 24 BE 0 E. pH 7.20 pCO2 63 HCO3 34 BE -5.6 Note: These numbers could be completely wrong, but you get the idea. |
A. pH 7.13 pCO2 55 HCO3 18 BE -9.1
Acute Metabolic & Respiratory Acidosis ----------- |
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AM45
Spinal correction is planned for a twelve-year-old girl with idiopathic scoliosis. Potential problems associated with this condition include A. diabetes insipidus B. laryngeal abnormalities C. mitral valve prolapse D. phaeochromocytoma E. renal artery stenosis |
C. mitral valve prolapse
- "Approximately 25% patients with idiopathic scoliosis have mitral valve prolapse, but this is rarely of clinical significance and antibiotic cover is given." (Michael A Entwistle , and Davandra Patel Scoliosis surgery in children Contin Educ Anaesth Crit Care Pain 6: 13-16.) ----------- |
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AM46 ANZCA Version [Jul06] Q150
Duchenne muscular dystrophy is a contra-indication to the use of A. corticosteroids B. non-depolarising neuromuscular blockers C. suxamethonium D. tramadol E. volatile anaesthetic agents |
C. Suxamethonium
- Wiki: Steroids now have a role in treatment - used to treat associated scoliosis Suxamethonium is contraindicated (Stoelting p517) Volatiles cause rhabdomyalysis in a similar way to sux but much less pronounced. they are relatively contraindicated for prolonged procedures, but my line is that for short simple procedures i would use them because my experience with TIVA in this age group is very limited. for major procedures i would refer to a paeds anaesthetist. Must use trigger free in DMD. Sux best answer, but examiners are out of date as usual. MIMS list Duchenne's as a contraindication for Sux - "The avoidance of certain anesthetic agents in DMD patients is an issue that continues to generate debate. Succinylcholine is contraindicated in DMD as it can cause acute rhabdomyolysis, hyperkalemia, and cardiac arrest. Inhalational agents can also cause acute rhabdomyolysis which may even mimic malignant hyperthermia (MH). Although DMD patients were thought to be at a higher risk for MH reactions, the evidence to date suggests that DMD and MH are indeed independent disease processes. The risk of MH in DMD patients appears to be the same as in the general population. At our hospital, volatile agents have been used for many years in DMD with no adverse events. As much of our surgical case load is corrective surgery for scoliosis, for which somatosensory and motor evoked potential monitoring is performed, a total intravenous technique is the anesthetic of choice. However, the consensus of opinion at our institution is that volatile anesthetic agents are not contraindicated and the use of a vapor-free machine is unnecessary. Additionally, nondepolarizing neuromuscular blocking agents appear to be safe in DMD, although the duration of action may be prolonged. Again the consensus at our hospital is that nondepolarizing neuromuscular blocking agents, such as rocuronium, may be used in doses lower than those typically required." Reference: WARWICK A. AMES MBBS FRCA, JASON A. HAYES MD FRCPC, MARK W. CRAWFORD MBBS FRCPC (2005) The role of corticosteroids in Duchenne muscular dystrophy: a review for the anesthetist Pediatric Anesthesia 15 (1), 3–8 ----------- |
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AM47 [Apr05]
In a patient with myasthenia gravis presenting for abdominal hysterectomy A. anticholinesterase therapy will have an effect on her plasma cholinesterase B. epidural analgesia is contraindicated C. preoperative sedation should be used D. there is an increased sensitivity to suxamethonium E. volatile agents should not be used |
A. anticholinesterase therapy will have an effect on her plasma cholinesterase
- A. Barash p850 and OHA suggest some effect on all esterases C. preoperative sedation should be used - false: "Premedication should be minimal" (OHA p246) D. there is an increased sensitivity to suxamethonium - false: "Suxamthonium may have an altered effect - patients may be resistant to depolarisation due to reduced receptor activity" (OHA) ----------- |
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AM48 [Jul07] [Apr08]
Shown a family tree... 6 year old boy coming for routine operation. Maternal Great Grandfather has had a malignant hyperthermia reaction under GA. Which of the following is most likely to rule out that the 8 year old will NOT suffer a MH reaction A. 8 year old has negative resting CK level B. 8 year old has had a previous operation before with no problems C. mother has had negative genetic testing D. grandfather has had negative muscle testing E. father has had an operation before with no problems |
D. grandfather has had negative muscle testing
or C. mother has had negative genetic testing - It all depends on what is on the family tree… see wiki. ➮ Halothane/Caffeine cantracture test is the "gold standard" ➮ Genetic testing is specific for known mutations tested ----------- |
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AM48 ANZCA Version [Jul 07] Q.147
A 4y.o. boy presents for insertion of grommets. His maternal great-grandfather is know to have had an episode of malignant hyperthermia. Which of the following is the strongest evidence that the boy is NOT susceptible to MH? A. the boy was exposed to halothane at age 2 with no sequelae B. the boy has recently been shown to have a normal serum creatinine kinase C. the boy's grandfather has had a negative muscle contracture test for MH D. the boy's mother has had negative molecular genetic testing for MH E. there have been NO other episodes of MH in the family despite exposure to known triggers on multiple occasions |
C. The boys maternal grandfather had a negative muscle contracture test for MH
- See stan's notes for family tree. ----------- |
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AM49 ANZCA Version [Apr 08]
Definitive evaluation of malignant hyperthermia (MH) susceptibility does NOT include observing: A. abnormalities on magnetic resonance imaging (MRI) spectroscopy B. calcium release from B lymphocytes in response to caffeine stimulation C. certain mutations in the ryanodine receptor gene D. myofibrillar necrosis on muscle biopsy E. plasma creatine kinase (CK) levels above 800 units.l-1 |
D. myofibrillar necrosis on muscle biopsy
false hence answer - A. MRI spectroscopy - true - Nuclear magnetic resonance spectroscopy measures the concentrations of ATP, phosphocreatine and other phosphomonoesters, along with pH, both in vivo and non invasively, in muscle and other tissue. Several studies have shown delayed reconstitution of pH, ATP, and increased phosphocreatine in MH patients during and after graded exercise. A recent study reports 100% concordance between abnormalities in adenosine triphosphate and high-energy phosphates produced by a specific exercise protocol and the results of muscle biopsy. B. Ca release from B lymphocytes in response to caffeine stimulation- true - Recently, Sei et al.22 have shown RYR-1 receptors on B lymphocytes in humans. This implied that these cells might demonstrate changes in calcium flux similar to those demonstrated in muscle. They found that lympho- cytes from MH patients, when incubated with 4-chloro- m-cresol, showed increased intracellular calcium con- centrations. However, halothane did not affect intracellular calcium concentrations. C. mutations in ryanodine receptor gene - true - Most recently, the demonstration that a mutation in the gene that encodes the calcium release channel (the ryanodine receptor, RYR-1) underlies porcine MH in- creased the expectation of a simple DNA-based test for MH in humans as well. D. myofibrillar necrosis on muscle biopsy - false E. plasma creatine kinase levels above 800 u/L - true- Creatine kinase concentrations are chronically in- creased in perhaps 50% of MH patients. - ----------- "Another approach has been the use of nuclear magnetic resonance spectroscopy to measure ATP, pH, creatine phosphate and other high-energy phosphates non-invasively. With exercise, MH susceptibles demonstrate a greater depletion of high-energy phosphates and fall in pH, compared to normals." Caffeine stimulated release of calcium from B Lymphocytes - "The B lymphocytes from MH patients also display exaggerated changes in cellular calcium levels upon exposure to caffeine and other calcium-release agents compared to normals." Resting CK >800 Muscle contraction on exposure to halothane - caffeine/halothane contracture test (CHCT) continues to be the gold standard Myofibrillary necrosis on histology - ASA Abstracts 2001 Histopathological Examination Does Not Improve Differentiation between Malignant Hyperthermia Susceptible and Normal Patients Frank Wappler, M.D.; Franziska von Breunig, M.D.; Marko Fiege, M.D.; Ralf Weisshorn, M.D.; Jochen Schulte am Esch, M.D. Department of Anesthesiology, University Hospital Eppendorf, Hamburg, Germany In contrast to the results of recent investigations in a small population of MH patients, histological differences between MHS and MHN could not be demonstrated. Histological investigations can neither improve MH diagnosis nor contribute to a better definition of the MHE status. Therefore, the IVCT remains the only reliable test method in diagnosis of MH susceptibility. However, histological examinations might be helpful to determine unknown neuromuscular diseases (e. g. central core disease, carnitine deficiency syndrome) in patients undergoing IVCT. |
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AM50 [Mar10]
For a person newly diagnosed as MH susceptible, which is true? A. ? B. Can have had an uneventful 'triggering' anaesthetic C. Recommended to use an anaesthetic machine which has not had volatiles through it D. ? E. There have been case reports of MH occurring up to 48 h post op |
B. Can have had an uneventful 'triggering' anaesthetic
> E. - B is TRUE - may have had an uneventful trigger-type anaesthetic previously. (Oxford Handbook of Anaesthesia, 2nd Ed, p260) C is not strictly true (depending how you interpret the question). If a machine that has never had volatiles through it is available then that's great, but in practice you need to remove the vaporisers, change the circuit and CO2 absorber, and flush with high fresh gas flows for 20-30 minutes. (Oxford Handbook of Anaesthesia, 2nd Ed, p263) E is TRUE also. Oxford Handbook states that rarely it can develop 2-3 days post-op and manifest as massive myoglobinuria +/- renal failure secondary to rhabdomyolysis. (Oxford Handbook of Anaesthesia, 2nd Ed, p260) ----------- |
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MM21 [Apr08][Oct08]
Serotonin syndrome: A. difficult to distinguish from NMS but it is not essential to differentiate as treatment is similar B. Has direct antidote promethazine C. May be contributed to by pethidine D. familial linkage (can't remember exact wording) - no, this option belonged in NMS question with options "Fever does not Always occur/ is related to MH/ major feature raised creatinINE kinase) E. is self limiting |
C. may be contributed to by pethidine
- see wiki. ----------- |
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NEW Myasthenia gravis, Eaton Lambert Syndrome What happens with exercise?
a. MG better, EL worse b. EL better, MG worse c. Both EL and MG get worse d. Both EL and MG get better |
b. EL better, MG worse
-- Myasthenia gravis (MG) - autoimmune disorder where antibodies form against ACh nicotinic receptors at NMJ -? reduction in number of ACh receptors at postsynaptic muscle membrane. Eaton lamber syndrome - impaired ACh release from motor nerve terminal due to autoimmune attack against voltage-gated calcium channels on PRESYNAPTIC motor nerve terminal results in loss of functional voltage gated Ca channels at motor nerve terminals. Myasthenia gravis more likely to present with weakness of extra ocular and bulbar muscles muscles. Eaton Lambert majority present with limb weakness. In Eaton Lambert syndrome - strength may improve after exercise then weaken as activity is sustained. ----------- |
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TMP-138 [Apr08] Q100
A 63-year-old, 70 kg man is in the recovery room following a lobectomy for small cell carcinoma of the lung. You are asked to review him because he is complaining of difficulty breathing. He is unable to lift his arms or flex his hips. He has a weak but sustained grip. Cisatracurium 8 mg was given 90 minutes previously. Neostigmine 2.5 mg and atropine 1.2 mg were given at the conclusion of the surgery. The likely diagnosis is: A. Eaton-Lambert syndrome B. limb-girdle muscular dystrophy C. myasthenia gravis D. myotonic dystrophy E. steroid myopathy |
A. Eaton-Lambert syndrome
- Associated with Small Cell lung tumours Lambert-Eaton myasthenic syndrome (LEMS) is a rare disorder of neuromuscular transmission. It is a presynaptic disorder of neuromuscular transmission in which quantal release of acetylcholine (ACh) is impaired, causing a unique set of clinical characteristics, which include proximal muscle weakness, depressed tendon reflexes, posttetanic potentiation, and autonomic changes. LEMS (Lambert-Eaton Myasthenic Syndrome) is the result of an autoimmune process in which antibodies develop to the VGCCs and impair the release of ACh from the presynaptic terminal. The same calcium channels in cell lines are found in SCLC, and they are also inhibited by LEMS-IgG, in both tumor and nontumor cases. In tumor cases, a protein of the calcium channel particles may trigger the autoantibody response, but the stimulus in the nontumor cases is unknown. Lambert-Eaton Myasthenic Syndrome http://www.emedicine.com/EMERG/topic292.htm ----------- |
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TMP-Mar11-038
Your registrar gives a Duchenne patient 1mg/kg of suxamethonium. What are you most worried about? A: hyperkalaemia B: rhabomyolysis C: MH |
A: hyperkalaemia
- From OrphanAnaesthesia 'Anaesthesia recommendations for patients suffering from DMD: 'Succinylcholine and volatile anaesthetics are best avoided because there is a risk of hyperkalemic cardiac arrest or severe rhabdomyolysis. There is no risk of malignant hyperthermia: some authors therefore agree that in special circumstances (e.g. difficult venous access) a short lasting use of inhalation anaesthesia is possible as long as the anaesthesiologist is prepared to treat acute rhabdomyolysis). ----------- |
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TMP-Oct09-042
[Mar10] A pregnant women whose paternal uncle has MH. What is the best test to exclude MH in this patient? A. Genetic testing of the patient B. Genetic testing of patient's father C. Muscle biopsy of the patient D. Muscle biopsy of patient's father |
C. Muscle biopsy of the patient
D. Muscle biopsy of patient's father Contentious due to the pregnancy although should be able to be done under LA. However British Malignant Hyperthermia Association state pregnancy is a contraindication to do biopsy! ----------- |
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TMP-Oct09-044
Disease associated with malignant hyperthermia a. central core disease b. myasthenia gravis c. myotonia congenita d. ? |
a. central core disease
- a. true - Autosomal dominant condition, 50% new mutations. Many due to mutation in ryanodine receptor, that is in same area as mutation thought to be responsible for MH. . A whole series of articles appears in A&A October 2009 which states that the following diseases could be MHS Central Core Disease Multiminicore Diease and Nemaline rod disease both having forms associated with RYR1 Mutation are considered high risk, despite the lack of case reports. (Apparently no one had used volatiles in patients know to have MmD!) Brody Myopathy King-Denborough Syndrome Hypokalaemic Periodic Paralysis is possible (they are not said to be MHS, but their risk of MH is above that of the general population) Stoelting & Dierdorf p719: The incidence of MH is NOT increased with Duchenne muscular dystrophy. Used to be thought so, but it is a different entity (hyperkalaemia due to sux and also volatiles due to an unstable sarcolemma) - see Orphanet article below. ----------- |
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TMP-Sep11-125
Compare to Myasthenia gravis, which symptoms is more likely to be Eaton Lambert syndrome? |
Myasthenia gravis (MG) - autoimmune disorder where antibodies form against ACh nicotinic receptors at NMJ -? reduction in number of ACh receptors at postsynaptic muscle membrane.
Eaton lamber syndrome - impaired ACh release from motor nerve terminal due to autoimmune attack against voltage-gated calcium channels on PRESYNAPTIC motor nerve terminal results in loss of functional voltage gated Ca channels at motor nerve terminals. Myasthenia gravis more likely to present with weakness of extra ocular and bulbar muscles muscles. Eaton Lambert majority present with limb weakness. In Eaton Lambert syndrome - strength may improve after exercise then weaken as activity is sustained. ----------- |
