poisoning by iron

1. Poisoning by Iron Altaf Ansari

3. Iron Toxicity Relative toxicity of Iron depends on the total amount of elemental Iron

4. Elemental Iron Equivalents Ferrous sulfate (anhydrous) 37% Ferrous sulfate (hydrated) 20% Ferrous gluconate 12% Ferrous fumarate 33% Ferrous chloride (anhydrous) 44% Ferrous chloride (hydrated) 28% Ferrous carbonate 12%

5. Dose Related Toxicity <20mg/kg non toxic 20-60mg/kg moderately toxic >60 mg/kg severely toxic 180-300 mg/kg lethal 30-45 tablets in a 10 kg child is lethal

6. Question 15 years old girl presents to ED Suicidal gesture. Ingested 60 tablets of Ferrous sulfate 300mg C/O hematemesis and bloody diarrhea once Embarrassed and remorseful now Wishes to be discharged home with parents

7. Question Vital signs: BP 96/62, HR 108/min, R 18/min, Temp 98.8 R Pulse Ox 98% RA Pain 2/10 Weight 50 Kg

8. Question What to do? Ipecac orally. Arrange out patient psyche follow up. Initiate Deferoxamine therapy. Obtain abdominal radiographs. Gastric lavage with Sodium bicarbonate.

9. Answer Ipecac Contra-indicated Out-patient Psych. Needs in patient ICU Deferoxamine. Abdominal radiographs indicated, not helpful if all Iron already absorbed. Gastric lavage with Bicarb. No data to show benefits

10. Why Deferoxamine? Ferrous sulfate=20% elemental Iron Each tablet = 300mg Iron Each tab = 300mg X 20% = 60mg Elemental Iron 60 tablets of Ferrous sulfate 300mg each = 3600mg Elemental Iron 3600mg/50 Kg = 72 mg/Kg ingested

11. Toxicity by Peak Serum Iron Level 50-150 mcg/dl normal <350 mcg/dl none to mild toxicity 350-500 mcg/dl moderately toxic >500 mcg/dl severely toxic to lethal

12. Risk of Coma by Peak Serum Iron Level <500 mcg/dl 10% 500-1000 mcg/dl 25% >1000 mcg/dl 75%

13. Iron Metabolism 15mg ingested daily 10% of ingested Fe absorbed daily Increased ingestion=Increased absorption

14. Iron Metabolism 1 mg of Fe lost daily through GI mucosa, bile, skin and urine 2 mg of Fe maximum is lost daily even with Fe overload 16 mg of Fe menstrual loss per month 1.5 mg of Fe per day transferred to fetus

15. Pathophysiology of Fe Toxicity Direct caustic effect on GI mucosa Direct myocardial depression Vasodilatation and increased capillary permeability Lactic acidosis, disrupts mitochondrial oxidative phosphorylation Catalyzes lipid peroxidation & free radicals

16. Stage 1 0-6 hours Nausea,vomiting, diarrhea upper or lower GI bleeding Abdominal pain, perforation, peritonitis Hypotension, tachycardia, shock Hyperglycemia, leucocytosis, metabolic acidosis

17. Stage 2 2-48 hours Apparent recovery GI symptoms subside False sense of security!!! Hyperglycemia, leucocytosis, acidosis persist

18. Stage 3 6-48 hours Multiple organ dysfunction syndrome Cardiovascular collapse Cerebral edema Pulmonary edema Renal failure Severe metabolic acidosis, leucocytosis, elevated PT

19. Stage 4 2-6 days Acute Hepatic Failure Jaundice Coma Abnormal LFTs, Elevated PT, Hypoglycemia

20. Stage 5 2-6 weeks GI scarring Gastric outlet obstruction Intestinal obstruction

21. Diagnosis Diagnosis of Fe poisoning should always be on clinical grounds!

22. Ancillary lab help leucocytosis hyperglycemia, later hypoglycemia metabolic acidosis abnormal LFTs Elevated Lactate KUB before and after lavage Serum Fe level >350 mcg/dl

23. ED Diagnosis of Fe poisoning Be persistent about History Obtain empty bottles and calculate amount of elemental Fe ingested Serum Fe level at presumed 4 hours, and a second level at 6-8 hours (sustained release?) Serum Fe level may be normal in Sage 3 Ancillary tests, and KUB

24. Treatment of Fe Toxicity Consult Poison Control Early!!! Airway, breathing, circulation 2 large bore IVs, cardiac & pulse ox monitors,oxygen Initial labs including Type and Crossmatch

25. Gastric Emptying Not neccessary if patient vomited and KUB negative Pills may clump together May erode mucosa and get embeded in sub mucosa Fe bezoars may require endoscopy or Gastrotomy

26. Fe Binding in GI Tract No activated charcoal (Poor Fe binding) Gastric lavage with Bicarbonate, Phosphosoda or Deferoxamine not recommended

27. Decrease GI Transit time No emetics or cathartics Whole Bowel Irrigation with Poly ethylene glycol or PEG-EL or Go-Lytely Given per NGT 1.5-2.0 liters per hour in adults 25 ml/kg/hr in children Continue for 5 hours or until Effluent=Infusate

28. Chelation Therapy, Deferoxamine Specific Chelator of Ferric Iron Fe +Deferoxamine=Ferrioxamine Ferrioxamine excreted in urine Ferrioxamine also dialyzable Limits Fe entry into the cell Also chelates Intracellular Fe

29. Deferoxamine 100 mg of Deferoxamine binds with 8.5 mg of elemental Fe. May be given IM or IV IV is the preferred method of administration

30. Deferoxamine Challange Test Give 50 mg/kg IM upto 1 gram Ferrioxamine gives “vin rose”color to urine Compare color of urine pre and post Deferoxamine If test Positive, start chelation If test Negative and no symptoms for 6 hrs, pt.may be discharged

31. Deferoxamine Negative Deferoxamine test by itself does not rule out Fe toxicity All the Fe may be intracellular by now Dose: 15 mg/kg/ hour IV until urine returns to normal color or toxicity disappears

32. Indications for Deferoxamine All symptomatic patients with more than 1 episode of vomiting or diarrhea All patients with abdominal pain, hypovolemia, acidosis, lethargy KUB with multiple opacities Even asymptomatic patients with SI 300-500 mcg/dl Pregnancy is not a contra-indication

33. Deferoxamine , Adverse Reactions Anaphlaxis, or anaphylactoid reactions Hypotension if given too fast Optic neuropathy, hearing loss Thrombocytopenia ARDS if given for >24 hrs

34. Deferoxamine, Adverse Reactions Acute renal failure Yersenia Enterocolitis (growth factor) Mucormycosis, Pneumocystis (T cell depression) Deferoxamine + Compazine = Coma

35. Severe Iron Toxicity Exchange transfusion Charcoal hemoperfusion Hemofiltration Hemodialysis after Deferoxamine Free radical Scavengers:vit C, vitE, Sulphdryl groups Liver transplant