What is LN’s creatinine clearance using Cockcroft and Gault equation based on IBW?

LN is 84 YOM who is in hospital for a back surgery. His height is 5 feet and 4 inches, weight 85 kg and NKDA.

His past medical history includes hypertension, diabetes mellitus, major depression, hypothyroidism and chronic back pain. Post-op day 1, LN’s medication includes Dexamethasone 8mg iv q6h with taper dosing, Ondansetron 4mg iv q6h prn for N/V, Levothyroxine 0.075mg po daily, Lisinopril 10mg po daily, Citalopram 20mg po daily, Docusate sodium / Senna 1 tab po twice a day, Bisacodyl 10mg suppository daily prn for constipation, Famotidine 20mg iv q12hr, Metoclopramide 10mg iv q6h, Metformin 500mg po bid, D51/2NS with 20K at 125mls/hour and Hydromorphone PCA at 0.2mg/hour of basal rate, demand dose 0.1mg. lock­out every 6min, one hour limit 2.2mg/hour. Pertinent morning labs includes serum creatinine 1.4mg/dl, Mg 1.5mg/dl, K 5.0mmol/L, Na 135mmol/L.

What is LN’s creatinine clearance using Cockcroft and Gault equation based on IBW?

A. 43 mls/min

B. 53 mls/min

C. 63 mls/min

D. 33 mls/min

E. 23 mls/min

View Answer

Answer: D

Explanation:

ABW = 85 kg IBW = 50 kg + 2.3 kg (4) = 59.2 kg 85/59.2 = 1.44 AdjBW = 59.2 kg + 0.4(85 kg-59.2 kg) =