Transcript How Can New Technology Improve Pain Management

CASE REPORT
Dr. Amr EL-Said
Professor Of Anaesthesia & Intensive Care Medicine
Faculty of Medicine – Ain Shams University
Magnesium Therapy for Acute
Management of Rapid Af
• 77 years old male patient was admitted to ICU on
14/10/2012 for post-operative care after subtotal
gastrectomy with primary anastomosis.
• Past history was unremarkable.
• Pre-operative lab investigations were within normal
limits.
• Pre-operative echocardiography was quite normal
apart from impaired diastolic function and trivial MR
and AR.
• Patient was haemodynamically stable.
• Follow up lab investigations including cardiac enzymes
were within normal limits.
• Patient was discharged from ICU following day.
• On 27/10/2012: patient was re-admitted to ICU at
11:00 pm with tachypnea and severe irregular
tachycardia but without cardiac decompensation.
• BP was normal and ABG analysis was satisfactory.
• ECG revealed AF.
• Last lab investigations were within acceptable levels.
• Blood work obtained in ICU were within normal limits.
• Chest X-ray revealed no parenchymal abnormality.
• DC cardioversion. After three successive electrical
shocks to heart with escalating levels of energy;
cardioversion was unsuccessful.
• Drug treatment. Loading dose of cordarone 300 mg
over one hour; tachycardia persisted.
• Magnesium sulfate infusion: 1gm/hour.
• After 6 hours, sinus rhythm was restored.
• Magnesium infusion was discontinued following day
at 10:30 am.
• On 29/10/2012: patient was discharged from ICU.
• Lone Atrial Fibrillation is AF without discernible cardiovascular
disease.
• AF potentially leads to prolonged hospitalization and significant
morbidity, particularly hemodynamic deterioration and
thromboembolic events especially stroke.
• AF has been associated with number of diseases primarily involving
organs other than heart.
• “Defective Substrate" has become integral to any discussion of cause
of LAF.
• Magnesium (Mg) deficiency has emerged as significant player in
etiology of LAF.
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Funk M, Richards SB, Desjardins J, Bebon C and Wilcox H. Incidence, timing, symptoms, and risk factors for atrial fibrillation after cardiac
surgery. Am J Crit Care 2003; 12: 424–33.
Burton MA. Magnesium: We Don't Appear to be Getting Enough. Science News Online. August 29, 1998.
• Mg involves maintenance of intracellular environment.
• Mg is also required cofactor in various membrane ATP pumps: Na/K;
Ca/Mg; K/H and Na/H pumps.
• Channels (such as Ca and Na) and exchangers (such as Na-Mg, Na-Ca and
Na-H).
• Mg is Ca channel blocker and Mg deficiency leads to increased
intracellular Ca.
• Mg deficiency also results in dysfunction of Na-Mg exchanger, leading to
increased intracellular Na.
• Mg deficiency also leads to leakage of primarily extracellular cations Na
and Ca into cells and primarily intracellular cations K and Mg out cells.
• Mg is antioxidant and Mg deficiency allows accelerated free radical
damage to cell membranes.
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Agus ZS. Hypomagnesemia. Journal of the American Society of Nephrology. 1999; 10 (7).
Larsen HR. Lone Atrial Fibrillation: Towards A Cure. 2003, pp. 96, 63.
Chambers P. Magnesium and Potassium in Lone Atrial Fibrillation. The Magnesium Web Site. MAGNESIUM ONLINE LIBRARY. Editor: Paul
Mason, February, 2003.
• Major cardiac effects of Mg are prolongation of atrial
and AV nodal refractory periods.
• Mg deficiency is relatively common in patients
presenting with AF [20% - 53%].
• Mg deficiency and AF are common after cardiac
surgery, and prophylactic Mg use has resulted in
significant reduction in incidence of post-operative AF.
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Christiansen EH, Frost L, Andreasen F, Mortensen P, Thomsen PE and Pedersen AK. Dose-related cardiac electrophysiological effects of
intravenous magnesium. A double-blind placebo-controlled dose response study in patients with paroxysmal supraventricular
tachycardia. Europace. 2000; 2: 320–326.
Eray O, Akca S, Pekdemir M, Eray E, Cete Y and Oktay C. Magnesium efficacy in magnesium deficient and non-deficient patients with
rapid ventricular response atrial fibrillation. Eur J Emerg Med. 2000; 7: 287–290.
Miller S, Crystal E, Garfinkle M, Lau C, Lashevsky I and Connolly SJ. Effects of magnesium on atrial fibrillation after cardiac surgery: a
meta-analysis. Heart. 2005; 91: 618–623.
• Randomized controlled trials comparing IV Mg versus placebo or
antiarrhythmic agents for acute management of rapid AF.
• Mg was more effective than control treatments with respect to rate
control and rhythm control.
• Overall response rate was 86% in Mg group and 56% in control
group.
• Time to response (in hours) was significantly shorter in Mg group
than in control group.
• Mg administration was also more effective than control treatments
in restoration of sinus rhythm.
• Risk of major adverse effect in Mg group was similar to that in
placebo group.
• Mg deficiency was in as many as 50% of patients presenting with AF.
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Onalan O, Crystal E, Daoulah A, Lau C, Crystal A and Lashevsky I. Meta-Analysis of Magnesium Therapy for the Acute Management of
Rapid Atrial Fibrillation. Am J Cardiol. 2007; 99: 1726–1732.
• Mg can be used safely in most patients in whom other
antiarrhythmic drugs are contraindicated or
considered harmful.
• Mg has relatively wide toxic/therapeutic window, and
most common reported side effects are transient
sensation of warmth and flushing.
• IV Mg has rapid action, which may be useful in
controlling symptoms.
• Mg is inexpensive, easy to use and titrate, and widely
available for immediate use in every clinical unit.
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Delva P. Magnesium and heart failure. Mol Aspects Med. 2003; 24: 79 –105.
Crippa G, Sverzellati E, Giorgi-Pierfranceschi M, Carrara GC. Magnesium and cardiovascular drugs: interactions and therapeutic role.
Ann Ital Med Int. 1999; 14: 40–45.