1 / 59

One drug, two stories

One drug, two stories. Dr FT Lee PMH/YCH AED. History (Patient A). 8-1-05 02:12 F/49 Known case of CRHD with MVR FU GH On Digoxin, Lasix, Acertil, Slow K. Aldactone, Warfarin. Attempt suicide with her husband by taking

len
Download Presentation

One drug, two stories

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. One drug, two stories Dr FT Lee PMH/YCH AED

  2. History (Patient A) • 8-1-05 02:12 • F/49 • Known case of CRHD with MVR FU GH • On Digoxin, Lasix, Acertil, Slow K. Aldactone, Warfarin

  3. Attempt suicide with her husband by taking Digoxin >100 tablets (0.25mg/tablet) & Acertil > 60 tablets at around 01:00 (1 hour before arrival) • Vomit twice

  4. P/E: • GCS: 14-15, refused to cooperate • BP: 152/49, P:49/min • RR:22/min, SaO2: 98% (Rm air) • Temp: 36°C • H’stix: 8.3

  5. Management in AED • 100%O2 • Cardiac monitor • NS Q4H • CXR: cardiomegaly • Consult ICU • Standby pacing • Transfer to ICU at 02:30 (13 mins) • BP:166/70, P:30/min

  6. Progress in ICU • Cardiac arrest at 02:50(38 mins) • Pulseless VT • Defibrillate 150J then 200J Asystole • TCP given but no cardiac output • Certified dead after 1 hr of active resuscitation • Adrenaline 1mg x 7 • Atropine 0.6mg x2 • NaHCO3 100ml

  7. Digitalis antidote was ordered but only available after prolonged resuscitation • RFT: Na: 131, K: 7.3, Urea: 7.4, Cr: 88 • INR: 1.6

  8. A sad story !!

  9. History (Patient B) • M/58 (Husband) • Good past health • Attempt suicide with his wife by taking Digoxin > 60 tabs, Acertil > 100 Tabs, Warfarin > 100 tabs, Piriton> 60 Tabs at 01:00 • Vomit

  10. P/E • GCS: 15 • BP: 151/65, P: 93/min • RR: 16/min, Sa O2: 99% (Rm air) • Temp: 37°C

  11. Management in AED • O2 • NS Q4H • Cardiac Monitor • CXR: NAD • Activated charcoal 50g po • Consult ICU (Suggest admission to Medical ward)

  12. Progress • Transfer to ICU at 05:40 (BP: 160/80, P: 100/min) • RFT: Na: 135, K: 4.8, Urea: 7.2, Cr: 90 • INR: 1.5 • 11:20 (10 hrs postingestion) P: 35-40/min, BP: 140/60, ECG: Complete Heart Block Atropine 0.6mg iv Transvenous pacing

  13. 11:25, 10 hrs postingestion Digoxin Level 10.7 nmol/l (1.3-2.6) • 13:45 (12 hrs postingestion) Digitalis Fab 480mg(6 vials) was given over ½ hour • 20:40 (7 hrs after Fab) Urticaria Piriton 10mg iv ECG: SR, 100/min

  14. 09-01-2005 (Day 2) INR: 2.8 • off pacing • Vit K1 10mg iv

  15. Digoxin Level Digitalis antidote

  16. Progress • To general medical ward on D3 • Claimed that he would commit suicide again • Psychiatric assessment: Adjustment disorder • Transfer to KCH by Vol form on D16

  17. An happy ending !!

  18. Acute Digoxin Overdose

  19. Mechanism • Inhibition of the Na-K-ATPase pump (70%)

  20. Normal depolarization & repolarization Depolarization Na-K-ATPase pump Na & Ca Ca

  21. Toxic Digoxin effect Elevate the resting potential predispose to dysrhythmia

  22. Toxic Digoxin effect (Autonom & Anta Pharm, Vol 25(2) 35-52)

  23. Rhythm disturbances • Increase automaticity particularly in the Purkinje fibre • Impaired conduction through the SA & AV node

  24. (Heart 2000;83:301-306)

  25. Extracardiac • Nausea, vomiting almost always present • Confusion and delirium • Seizure (very rare)

  26. Toxicokinetic • Toxic dose: >3mg in Adults >1mg in Child • Large volume of distribution (Vd: 5-10 l/kg)

  27. Toxicokinetic • Two-compartment system ka k12 Compartment 1 (Serum) Compartment 2 (Tissue) k21 kel

  28. Toxicokinetic • Peak effect occurs after a delay of 6-12 hours • Eliminated by kidney (60-80%) • Elimination half-life: 1.6 days

  29. Hyperkalaemia • An accurate predictor of outcome (Bismuth et al; J Toxicol Clin Toxicol 6: 153-162, 1973)

  30. Digoxin Level • Tissue distribution completes in 6-12 hours • Not correlate accurately with severity of intoxication • Other metabolic abnormalities must take into consideration • Falsely elevated after Digibind

  31. Management • ABC • Decontamination • Antidote

  32. Management of dysrhythmia

  33. Treatment of dysrhythmia • Bradydysrhythmias • Atropine • Caution with electrical pacing • Trigger fatal arrhythmia or delay Fab • Failed in 23% of patient (vs 8% treated with Digibind) • Iatrogenic accidents in 36% vs 0% in Digibind (p<0.05) (Taboulet et al; J Toxicol Clin Toxicol 31: 261-273, 1993)

  34. Treatment of dysrhythmia • Tachydysrhythmia • Cardioversion may precipitate refractory VT, VF or asystole • Start with very low energy (10-25J) • Pretreated with Lidocaine or Amiodarone • Digitalis Fab

  35. GI decontamination • Orogastric larvage • increase vagal tone • Activated Charcoal • Multiple dose Activated Charcoal is effective (Silva et al; Lancet 2003;361:1935-38)

  36. Treatment of Hyperkalaemia • K>5mmol/l is an absolute indication for Digibind (Elliot et al; Circulation 1990;81;1744-52)

  37. Treatment of Hyperkalaemia • Insulin/glucose, NaHCO3 • Ca must not be given except after Digibind • Correction of hyperkalaemia does not improve survival (Bismuth et al; J Toxicol Clin Toxicol 6: 153-162, 1973)

  38. Antidote Digoxin Immune Fab

  39. Digoxin Immune Fab • Produced in immunize sheep • Greater binding affinity for digoxin than Na-K ATPase • Fab fragment-digoxincomplex eliminated through kidney (T1/2: 15-20 hrs)

  40. Pharmakokinetic • Creates a concentration gradient to dissociate digoxin from the heart Compartment 2 Digoxin at Myocardial receptor Compartment 1 Serum & Intersitial free Digoxin Increase renal clearance by 20-30%

  41. Effectiveness • Resolution of all signs/symptoms (80%) • Improvement (10%) • No response (10%) • Response within 1 hour (mean:19 mins) and complete within 4 hours (TW. Smith American J of Emerg Med, March 191:1-6)

  42. Decrease mortality (Antman et al; Circulation 1990;81;1744-52)

  43. Improve survival rate in digitalis-induced cardiac arrest (Gaultier et al La Rev d Practicien 1978; 28:4565-4579) (Elliot et al; Circulation 1990;81;1744-52)

  44. Indications • Rhythm & Conduction disturbances • Hyperkalaemia (>5mmol/l) • Digoxin ingestion >10mg (>4mg in child) • Serum digoxin level 15ng/ml (19nmol/l) at any time or >10ng/ml (13nmol/l) 6h postingestion

  45. Factors affecting the efficacy • Time of administration • Dosage • Rate of administration

  46. Dosage • Amount of ingestion and post distribution Digoxin level is unknown • Amount of ingestion is known • Post distribution Digoxin level is known

  47. Dosage • The brand of Digoxin Fab

  48. Digitalis Antidote (Roche) Available in PMH 80mg/vial Each vial binds 1 mg digoxin Digibind (Glaxo) 38mg/vial Each vial binds 0.5mg digoxin

More Related