A patient on haemodialysis attends on Mondays and Thursdays. On which day should elective dental treatment be scheduled?

Correct answer: C. Tuesday

• A. Sunday is two days after Thursday's session — the point of maximum accumulation of uraemic toxins and fluid, and the least favourable time.
• B. Thursday is the other dialysis day, with the same objections.
• C. CORRECT. TUESDAY — the day AFTER a dialysis session. Treating the day after dialysis means the patient is at their metabolic best: uraemic toxins, fluid overload and potassium are at their lowest, and the heparin given during dialysis has cleared (its half-life is only 1–2 hours, and it is effectively gone within 4–6 hours).
• D. Monday is a dialysis day. Treating on the day of dialysis means either an unwell, fluid-overloaded patient before the session, or a heparinised, hypotensive and fatigued patient after it.

Note: Other essentials in dialysis patients: never take blood pressure from or place a cannula in the arm bearing the arteriovenous fistula; avoid nephrotoxic drugs (NSAIDs, aminoglycosides, tetracyclines) and adjust doses of renally cleared agents; expect anaemia, a bleeding tendency from platelet dysfunction, and secondary hyperparathyroidism with a ground-glass jaw pattern.