What is the next step in managing a patient with end-stage renal disease (ESRD) on hemodialysis who experienced chest pain during their 9th IV iron administration, which resolved after stopping the infusion, and is currently being treated with oxygen (O2) inhalation and Isordil (isosorbide dinitrate) 5mg?

Management of Chest Pain During IV Iron Administration in Hemodialysis

Immediately discontinue IV iron permanently in this patient and pursue cardiac evaluation, as chest pain during infusion that resolves with cessation represents a serious adverse reaction requiring investigation for underlying cardiac pathology before any consideration of rechallenge. 1

Immediate Actions Already Taken (Appropriate)

• Stopping the IV iron infusion was correct – chest pain resolution after discontinuation confirms a temporal relationship between the infusion and symptoms 1
• Oxygen administration is appropriate – supports tissue oxygenation during potential cardiac ischemia 2
• Isosorbide dinitrate 5mg is reasonable – addresses potential vasospasm or cardiac ischemia, though this dose may need adjustment based on blood pressure response 2

Critical Next Steps

1. Cardiac Assessment (Priority)

• Obtain immediate 12-lead ECG to evaluate for ST-segment changes, T-wave inversions, or arrhythmias that would indicate acute coronary syndrome 1
• Measure cardiac biomarkers (troponin, CK-MB) immediately and serially at 3-6 hours to rule out myocardial injury 1
• Monitor vital signs continuously for at least 60 minutes post-event, as hypotension and cardiovascular complications can occur with IV iron reactions 1
• Assess for signs of anaphylactoid reaction including hypotension, flushing, dyspnea, or urticaria, though chest pain alone may represent cardiovascular instability 3, 1

2. Determine Reaction Severity

This represents at minimum a moderate adverse reaction requiring documentation and alternative management strategies 4

• Chest pain during infusion is classified as a significant adverse event, not a minor reaction like arthralgias/myalgias 3
• The fact this occurred on the 9th administration suggests either cumulative toxicity or coincidental cardiac disease unmasked by hemodynamic stress 1

3. Alternative Iron Management Strategy

Do NOT rechallenge with IV iron until cardiac evaluation is complete 1, 4

If cardiac workup is negative and iron supplementation remains necessary:

• Consider switching to oral iron (100-200mg elemental iron daily) if TSAT <20% and ferritin <100 ng/mL, though efficacy is limited in hemodialysis 3
• If IV iron is absolutely required after cardiac clearance, consider:
  • Switching to a different IV iron formulation (e.g., from iron dextran to non-dextran preparations like iron sucrose or ferric gluconate, which have lower anaphylactoid risk) 3, 1
  • Reducing dose to 62.5mg and extending infusion time to 4 hours during dialysis to minimize hemodynamic stress 3
  • Premedication strategies remain controversial with conflicting evidence, but may be considered 4

4. Reassess Iron Status Before Any Future Iron

• Verify current iron parameters (TSAT, ferritin) to determine if continued iron therapy is even necessary 3, 5
• Withhold IV iron if ferritin >500 ng/mL or TSAT >50%, as supplementation above these levels is potentially harmful 3, 5, 1
• Exclude active infection before any future iron administration, as infection is a contraindication 5, 1

Critical Pitfalls to Avoid

• Do not assume this is simply "chest discomfort" from rapid infusion – chest pain in a dialysis patient warrants full cardiac evaluation given high cardiovascular risk 1
• Do not rechallenge with the same IV iron formulation without cardiac clearance – severe reactions including anaphylaxis can occur on rechallenge, and cardiac events may be unmasked 3, 1, 4
• Do not continue IV iron based solely on anemia management goals – balance the risks of adverse reactions against benefits, particularly when alternatives exist 3
• Do not overlook that this patient may have underlying coronary disease – hemodialysis patients have extremely high cardiovascular morbidity, and IV iron can cause hypotension and hemodynamic stress that precipitates ischemia 1, 6

Monitoring Isosorbide Dinitrate

• Monitor blood pressure closely – hypotension is a major adverse effect, particularly in dialysis patients prone to intradialytic hypotension 2
• Usual maintenance dosing is 10-40mg two to three times daily, but initial 5mg dose is appropriate for acute management 2
• Ensure dose-free interval of at least 14 hours to prevent nitrate tolerance if continued therapy is needed 2

Documentation Requirements

• Document this as a serious adverse reaction in the patient's medical record to prevent inadvertent re-administration 1
• Report to institutional adverse event monitoring if applicable 1
• Communicate clearly with dialysis team that IV iron is contraindicated pending cardiac evaluation 1