Cost analysis project : Ordering Magnesium and Phosphorus Pouneh Nasseri R2 12/17/12

Research Objective : To investigate how often magnesium and phosphorus are ordered, if it has an appropriate indication, and to determine the excess cost associated with inappropriate orders.

METHODS Study site: UCI medical center Patient population : 50 Patients admitted to UCI ward team. All adults > 18 yrs of age Study design : – Retroperspective chart review of all patients admitted to UCI ward teams for a 4 day period – Determining if admission diagnosis had an indication for ordering mag and phosphorus – Interviewing the seniors of the team to analyze if patient had other indications for ordering mag and Phosphorus, and if daily monitoring of normal values was necessary.

Indications for ordering Magnesium Renal failure patient : Acute, chronic Alcoholism Medications : PPI, Diuretics Other electrolyte abnormalities: Hypocalcaemia, hypokalemia (especially refractory) Neuromuscular disease Arrhythmias (ventricular) Acutely ill diabetics Malnutrition/malabsorption Diarrhea

Indications for ordering Phosphorus Malnutrition/malabsorption Other electrolyte abnormalities (hypocalcemia, hypomagnesium, hypokalemia) Rhabodomyolysis Alkalosis/ Acidosis Malignancy/ Tumor lysis syndrome Renal failure: acute, chronic Acutely ill diabetic Hyperglycemia Hyper/hypo parathyroidism Sepsis Alcoholism Diarrhea/ laxative abuse/ bowl prep for colonoscopy

Simple guideline for ordering Mag and Phos Group 1: Renal failure ( acute/chronic ) Group 2: Diabetics ( Acutely ill/ hyperglycemia ) Group 3:High risk patients for malnutrition state Group 4: Diarrhea/laxative/bowel prep Group 5: Electrolyte abnormalities Group 6: Cancer patients (active cancer) Group 7: Alcoholics Group 8: Acutely ill patients : Sepsis, neurological symptoms and deficits, generalized weakness, Arrhythmias.

COST At UCI Magnesium : $5 Phosphorus : $5

Results Out of 50 patients analyzed on 7 did not have their phosphorus or magnesium checked during their hospitalization and all 7 did not have any indications for checking magnesium and phosphorus based on the guidelines made Out of 43 who had magnesium and phosphorus ordered 8 (18.6%) had no indications for ordering Mag and Phos and 35 (81.4%) had one or more indications to order initial magnesium and phosphorus

RESULTS Some patient meet 2 or more criteria for ordering labs Group 1: Renal failure ( acute/chronic ) 7 Group 2: Diabetics ( Acutely ill/ hyperglycemia ) 2 Group 3:High risk patients for malnutrition state 5 Group 4: Diarrhea/laxative/bowel prep 6 Group 5: Electrolyte abnormalities 6 Group 6: Cancer patients (active cancer) 4 Group 7: Alcoholics 4 Group 8: Acutely ill patients : Sepsis, neurological symptoms and deficits, generalized weakness, Arrhythmias. 9

RESULTS Out of 43 patients only 10 patients had abnormalities in either magnesium or phosphorus (or both) Out of these 10 patients, 5 continued to have daily abnormal values.(Out of those 5 : 3 were dialysis patients, 1 was malnourished, 1 was septic) Out of 43 patients 33 patients had repeating labs ordered.

RESULTS 18.6 % of patients had no indication of initial order of mag and phos ($80) 65% of patient had unnecessary daily Mag and Phos ordered Daily unnecessary cost was around $ 250 dollars Extrapolated to a week = $1750 Extrapolated to a year = $ 91,250

Conclusion We as residents do have a culture of ordering unnecessary daily labs In regards to Magnesium and phosphorus, overall our initial order of magnesium and phosphorus seems to be indicated However we repeat labs even if values are normal and also when underlying condition causing abnormal values are being treated or have resolved. Even though Magnesium and phosphorus do not cost much, in the bigger picture everything adds up to our overall high cost of healthcare

Conclusion Limited study – The cost of Mag and Phos is the cash value without insurance coverage – It’s a snap shot of only 4 days. Can be attending /resident based – The Extrapolation is not really a valid representation – Small sample size