- What to monitor (and when):
- Before starting (≤ 7 days prior):
- BMP / eGFR + electrolytes:
- Cr, BUN, Mg, K, Ca, Na, PO₄
- Urinalysis if concern for renal injury
- Why:
- Baseline renal reserve; cisplatin causes salt wasting (especially Mg) and AKI eviQ
- Why:
- CBC with differential:
- Why:
- Myelosuppression risk DailyMed+1
- Why:
- Audiology (baseline audiogram):
- Why:
- Ototoxicity risk:
- Establish baseline threshold:
- Audiology societies and monographs recommend baseline and interval monitoring American Academy of Audiology+2audiology-web.s3.amazonaws.com+2
- Establish baseline threshold:
- Ototoxicity risk:
- Why:
- Medication review and vitals / weight.:
- Hold / avoid nephrotoxins:
- NSAIDs, IV contrast, aminoglycosides
- Assess fluid status eviQ
- Hold / avoid nephrotoxins:
- Antiemetic plan (cisplatin = high emetic risk):
- Day 1:
- NK1RA + 5-HT3RA + dexamethasone + olanzapine
- Continue dexamethasone ± olanzapine Days 2 to 4 American Society of Clinical Oncology+2Janet Abrahm, M.D.+2
- Day 1:
- BMP / eGFR + electrolytes:
- Each cisplatin day (same day or within 24 to 48 hour before dose):
- BMP / eGFR + Mg / K / Ca / Na / PO₄ and CBC
- Act:
- Replete Mg (often 10 mmol MgSO₄ pre-hydration) and correct K / Ca before dosing
- If eGFR ↓ or SCr ↑:
- Evaluate per KDIGO, hydrate, and hold / modify eviQ
- Act:
- Hydration status and urine output:
- Act:
- Use isotonic saline pre / post hydration:
- Typical total 2.5 to 3.0 L around infusion
- Routine mannitol not required:
- Consider only for very high-dose eviQ
- Use isotonic saline pre / post hydration:
- Act:
- Symptom screen:
- Tinnitus, hearing change, paresthesias, nausea / vomiting, cramps (hypo-Mg), mucositis, dysphagia
- Act:
- Audiogram if otologic symptoms
- Neuro exam each visit American Academy of Audiology+1
- BMP / eGFR + Mg / K / Ca / Na / PO₄ and CBC
- Weekly during RT (even if cisplatin is q3-weekly):
- BMP / eGFR + Mg / K / Ca (at least weekly), CBC weekly, weight, I/Os
- Why:
- Catch AKI and hypomagnesemia early
- Track cytopenias and dehydration eviQ+1
- Why:
- Audiology:
- Repeat before each cycle (q3-weekly) or sooner if symptoms; for weekly cisplatin, obtain symptom-triggered or mid-course checks per local protocol American Academy of Audiology+1
- BMP / eGFR + Mg / K / Ca (at least weekly), CBC weekly, weight, I/Os
- Before starting (≤ 7 days prior):
- What to do with common issues?
- Rising creatinine / suspected AKI:
- Trigger:
- ≥ 0.3 mg/dL increase or ≥ 1.5 × baseline (KDIGO stage 1+):
- Hold cisplatin, hydrate (NS), replete Mg / K, stop nephrotoxins, reassess in 24 to 72 hours
- ≥ 0.3 mg/dL increase or ≥ 1.5 × baseline (KDIGO stage 1+):
- Escalate care by stage Merck Manuals+1
- Trigger:
- Hypomagnesemia (very common):
- Prevention / correction:
- Include MgSO₄ in pre-hydration (e.g., 10 mmol in 1 L NS) and replete as needed:
- Mg protects against cisplatin nephrotoxicity eviQ+1
- Include MgSO₄ in pre-hydration (e.g., 10 mmol in 1 L NS) and replete as needed:
- Prevention / correction:
- Emesis despite prophylaxis
- Action:
- Optimize 4-drug regimen (ensure NK1RA)
- Consider scheduled olanzapine days 2 oto 4
- Add rescue (metoclopramide, prochlorperazine) American Society of Clinical Oncology+1
- Action:
- Ototoxicity symptoms (tinnitus, high-frequency loss):
- Action:
- Prompt audiogram:
- If confirmed / worsening:
- Discuss dose holding or regimen change (risk rises with cumulative dose) American Academy of Audiology+1
- If confirmed / worsening:
- Prompt audiogram:
- Action:
- Rising creatinine / suspected AKI:
- Hydration—practical template (adjust per institution):
- Pre-hydration:
- 1 L NS over ~ 60 min with 10 mmol MgSO₄
- Cisplatin infusion:
- 1 L NS over ~ 60 min (institutional)
- Post-hydration:
- 1 L NS over ~ 60 min:
- Encourage oral fluids (≥ 500 mL if tolerated)
- 1 L NS over ~ 60 min:
- Mannitol / diuretics:
- Not routine; consider case-by-case (e.g., very high-dose) eviQ
- Pre-hydration:
- One-look table (what/why/act);
- BMP / eGFR + Mg / K / Ca / Na / PO₄ (baseline and weekly):
- Nephrotoxicity / salt wasting → hydrate, replete Mg / K, hold if AKI eviQ
- CBC weekly:
- Myelosuppression → delay / modify if grade ≥ 3, treat per protocol DailyMed
- Audiogram baseline ± before each cycle / PRN:
- Ototoxicity → hold / switch if worsening American Academy of Audiology
- Antiemetics each dose:
- Cisplatin = high emetic risk → 4-drug prophylaxis American Society of Clinical Oncology
- BMP / eGFR + Mg / K / Ca / Na / PO₄ (baseline and weekly):
- Bottom line:
- Weekly labs (BMP / eGFR, Mg / K / Ca) + CBC
- Disciplined hydration with Mg supplementation
- Symptom-triggered audiology are the pillars that prevent missed AKI, hypomagnesemia, cytopenias, and ototoxicity during CRT with cisplatin
Rodrigo Arrangoiz MS, MD, FACS, FSSO 