Policy: Created: 2/11/2015; Approved: Adult Pharmacokinetic Dosing and Monitoring- Vancomycin Dosing

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1 ProMedica Health System Clinical Interdepartmental Policy and Procedure: Section: Policy: Date: Subject: Pharmacy Created: 2/11/2015; Approved: Adult Pharmacokinetic Dosing and Monitoring- Vancomycin Dosing I. Purpose: A. To establish evidence based guidelines for pharmacist to dose vancomycin when consulted by a physician. II. Background: Pharmacokinetics is a technique for using patient specific criteria to mathematically determine dosing requirements that will maintain appropriate therapeutic levels in the patient. The patient specific parameters that are determined are drug half life (t 1/2), clearance (Cl), elimination rate constant (ke), volume of distribution (Vd), and projected steady state levels. These characteristics are then used to predict serum drug levels resulting from recommended dosage regimens. III. Policy: The Pharmacy Department provides a Pharmacokinetic Dosing and Monitoring Service for Vancomycin Dosing. All patients receiving parenteral vancomycin are followed by a pharmacist daily. The pharmacist assumes responsibility of dosing and ordering levels when providers enter a Pharmacist Consult. Because of the complexity of pharmacokinetic dosing, the Dosing/Monitoring Service develops protocols for vancomycin dosing. These guidelines are reviewed and approved by the Pharmacy and Therapeutics Committee and the Medical Executive Committee. Approved nomogram is listed for dosing vancomycin (Appendix A). IV. Responsibility a. PRESCRIBER i. Place an order for the desired drug. ii. Include the route of administration. iii. Order Pharmacy Consult, if desired. iv. Countersign orders placed by the pharmacist per consult request within the guidelines of the hospital policy. v. Change or discontinue orders placed by the pharmacist when appropriate. vi. Discontinue the drug therapy when appropriate vii. Communicate appropriate information including problems with the Dosing Service to the pharmacy. viii. Monitor patient s outcomes, desired effects and adverse effects of drug therapy. ix. Monitor serum drug levels periodically and adjust the dose when necessary. x. Monitor renal function while the patient is receiving vancomycin. b. PHARMACIST i. Assess each new pharmacokinetic dosing request within a time period appropriate for the drug, patient condition, and situation as further delineated in each drug guideline.

2 ii. Pharmacokinetic Dosing and Monitoring forms are to be initially completed and updated daily by the responsible pharmacist (Appendix B). 1. Monitoring forms should be filled out for ALL intravenous vancomycin orders iii. Follow the guidelines established for vancomycin dosing (Appendix A). iv. Forward any active request to the designated pharmacist on the next shift. v. Follow guidelines to monitor therapy and make suggestions regarding therapy. vi. Communicate all recommendations to the prescriber. 1. Place Pharmacy Consult Notes in the chart when appropriate 2. Page the provider when scr increases greater than 0.5 mg/dl from previous day c. CLINICAL PHARMACY SPECIALIST/ DEPARTMENTAL DESIGNEE i. Review and analyze pharmacokinetic requests retrospectively against the following Quality Assurance criteria 1. Initial dosing for compliance with protocol a. Dose in mg/kg and frequency of maintenance dose 2. Initial trough concentrations 3. Number of trough levels >target 4. Number of trough levels < target 5. Number of levels ordered 6. Duration of therapy 7. Nephrotoxicity ii. These criteria assure quality in the process completed by the pharmacist. Evaluation and corrective actions are the responsibility of the Clinical Pharmacy Specialist of departmental designee. 1. Maintain appropriate records on the Pharmacokinetic Service including volume indicators and Quality Assurance results. Report these to antimicrobial subcommittee meeting quarterly 2. Provide feedback to the pharmacists on quality and quantity of pharmacokinetic requests. d. NURSING i. Will not shorten vancomycin dose interval unless ordered by the prescriber. ii. May delay administration of these drugs to complete the administration of a unit of blood. iii. If a delay in administration occurs, accurately document the exact time of the beginning of the drug infusion on the Medication Administration Record. iv. Begin all drug infusions within 30 minutes before or after the scheduled administration time. v. Ensure appropriate timing of blood draws when serum drug concentrations are ordered. See individual appendices. vi. Ensure that vancomycin IV piggyback is not infusing at the time a blood sample is to be obtained for the purpose of measuring a serum drug level.

3 Appendix A: Vancomycin Dosing Guidelines Procedures: Upon Receipt of an order for pharmacy to dose vancomycin, the pharmacist will obtain essential patient information. This includes but not limited to the following: a. Gender b. Height and weight c. Allergies d. Serum creatinine (Scr) and BUN **If over 2 days old, reorder** e. WBC and Tmax f. Indication for vancomycin / other pertinent diagnosis(es) g. Culture and sensitivity data h. Concurrent antibiotics Determining Initial Dosing Regimen: A. Calculate the patients estimated creatinine clearance using Cockcroft-Gault method i. Ideal Body Weight Calculations (IBW): For Males: IBW (in kilograms) = 50 + [2.3x (height in inches minus 60)] For Females: IBW (in kilograms) = [2.3x (height in inches minus 60)] ii. IBW for Amputees 1 : If patient has an amputation, deduct a certain percentage off the estimated IBW based on the area amputated (decrease IBW by the following percentages): o Total Arm: 4.9% Hand: 0.7% Forearm: 1.6% Upper arm: 2.6% o Total Leg: 16.1% Foot: 1.5% Calf :4.3% Thigh: 10.3% iii. Cockcroft-Gault Equation For Males: Clcr = (140-Age) x (IBW) Scr x 72 For Females: Clcr = (140-Age) x (IBW) x 0.85 Scr x 72 iv. Notes for Cockcroft-Gault Calculations: If patient s total body weight (TBW) is less than their IBW, use TBW If patients less than 5 feet tall, use IBW=50 kg for males and 45.5kg for females In adults > 65 years of age and Scr <0.8 mg/dl, round to 0.8 mg/dl

4 B. Establish Goal Trough level based on Indication 2 : Table 1: Vancomycin Trough Target based on Indication Indication Desired Trough UTI mcg/ml Cellulitis mcg/ml Abscess Bacteremia/Sepsis Pneumonia Osteomyelitis Endocarditis Meningitis Pre-HD level T Vancomycin MIC >1 T Pre-HD levels will be drawn with AM labs on days patients will receive hemodialysis. Goal level of is based on providing AUC/MIC of ~ mcg/ml 3 C. Loading Dose 2 : mg/kg use TBW a. Applicable to patients with goal trough of or patients severely ill i. Loading dose should be given regardless of renal function b. Maximum dose = 2.5gm (round to nearest 250 mg) c. Review patient profile to ensure patient has not already received vancomycin before ordering a loading dose. i. If patient meets criteria for a loading dose and has recently received a dose of vancomycin (e.g 1000 mg x 1 in ER), a subsequent booster dose can be given to reach a total combined dose of 20-25mg/kg. D. Maintenance Dose: a. For stable renal function: I. Goal trough mcg/ml: Maintenance dose 15 mg/kg i. Initial range can be 15-17mg/kg II. Goal trough : Maintenance dose 18 mg/kg III. i. Initial range can be mg/kg Maximum initial dose=2 gm (round to nearest 250 mg) i. After level is obtained, maximum maintenance dose can go up to 2.5 gm ii. Total daily dose for initial therapy should not exceed 4 gm b. Patients on hemodialysis 4 : I. Weight base dosing: i. <70 kg: 500 mg post dialysis ii kg: 750 mg post dialysis iii. >100 kg: 1000 mg post dialysis

5 E. Dosing Interval and Timing of Levels Table 2: Guidelines for Vancomycin Dosing Interval and Level Monitoring CrCl (ml/min) Interval Level Monitoring Ɨ > 75 ml/min and < 35 years old Q8H Trough Before 4 th dose > 70 Q12H Trough Before 4 th dose Q12H or Q18H Trough Before 4 th dose Q24H Trough Before 3 rd Q48H Trough Before 2 nd <25 ⱡ Dose by level Intermittent HD Post HD dosing Random level within 48 hours from last dose; re-does when level in therapeutic range Pre-HD level * on the day that the 3 rd vancomycin dose will be due Ɨ Trough levels are to be drawn 30 minutes prior to next scheduled dose ⱡ When dosing by level, RPh will enter vancomycin 1mg IV PRN as a place holder to notify all other health care providers that the patient is on vancomycin * Pre-HD levels are to be drawn with AM labs on days patients will be receiving dialysis a. Monitoring Levels: I. Vancomycin level obtainment is appropriate in the following situations: 1. If therapy to continue 4 days 2. Morbidly obese patients 3. Patients with unstable or unpredictable renal function 4. Patients require high serum concentrations of vancomycin to penetrate selected sites of infection (e.g. endocarditis, osteomyelitis, CNS infections) II. Once level stable, repeat trough weekly while patient still on vancomycin, or upon any significant changes in renal function

6 F. Evaluation of Trough Levels: a. Stable renal function: Table 3: Interpreting Trough Levels Action Needed / Trough Goal and Levels mcg/ml mcg/ml Q48H Q24H, keep same dose Q24H Q12H, keep same dose Q18H Q12H, keep same dose Q12H Q8H, keep same dose Q8H increase dose by 250 mg, keep same interval < 8 mcg/ml <10 mcg/ml Increase dose by 250 mg, keep same interval mcg/ml mcg/ml No Changes mcg/ml mcg/ml Decrease dose by 250 mg, keep same interval mcg/ml mcg/ml Q8H Q12H, keep same dose Q12H Q24H, keep same dose Q18H Q24H, keep same dose Q24H Q48H, keep same dose Hold Dose and recheck random level after 2 doses of old regimen have passed mcg/ml mcg/ml >25 >30 b. Hemodialysis patients I. Pre-Hemodialysis level > 25 mcg/ml: Hold dose and recheck random level morning of next hemodialysis II. Pre-Hemodialysis level 21-25: Decrease maintenance dose by 250 mg III. Pre-Hemodialysis level : No change IV. Pre-Hemodialysis level mcg/ml: Increase maintenance dose by 250 mg V. Pre-Hemodialysis level <10 mcg/ml: increase maintenance dose by 500 mg G. Scr/BUN Monitoring: a. Scr/BUN drawn at baseline and at least every 3 days while on vancomycin b. More intensive Scr/BUN monitoring when renal function is unstable, or if nephrotoxic drugs are administered concomitantly (e.g. aminoglycosides or amphotericin B, cyclosporine A) I. Monitor Scr/BUN every other day c. If Scr increases greater than 0.5mg/dL, stop vancomycin and order a random level when next dose would have been due. I. Contact prescriber to inform him of increase in scr

7 H. Infusion Rates Table 3: Vancomycin Infusion Times Dose Infusion Rates (minutes) < 1,000 mg 60 1, mg 90 1, mg 120 2,500 mg 150 The above dosing are GUIDELINES that the pharmacist will use in conjunction with clinical judgment when selecting appropriate dosing for patients.

8 Name ProMedica Hospital Monitoring Form Pharmacokinetic Dosing & Monitoring Form Fill in all fields. Please PRINT legibly APPENDIX B MRN ADMISSION # DATE OF BIRTH / / Addressograph Admission Date / / Room # Service Prescriber Pharmacy Consult Ordered? No Yes. Date ordered: / / ; Order Number: Antibiotic : Reason: Prophylaxis History, including current diagnosis(es) and other pre-existing conditions: Empiric Treatment Allergies: Date Day of Therapy BUN (mg/dl) SCr (mg/dl) Tmax (C) WBC (X 10 9 /L) % Segs % Bands ANC Platelets (X 10 9 /L) Est. Cl Cr (ml/min) Urine Output (peds ml/kg/hr) I/O net Hemodialysis Weight (kg) Peak/Tr Time Ordered Date Specimen (Site) Gram Stain Organism(s) Susceptibility(ies) CONCOMITANT ANTIMICROBIAL MEDICATIONS Start Date Stop Date Medication Regimen (Drug Name/Dose/Route/Interval) Start Date Stop Date Medication Regimen (Drug Name/Dose/Route/Interval) OUTCOME DATA Initial Dose (mg/kg) Frequency If Pharmacy to Dose- Dose based on policy? Yes No Duration of Therapy If no, Reason? (e.g. clinical judgment) Initial Peak/Trough: mcg/ml Number of Pk/t r> goal Number of Pk/ tr <goal Total # levels Did patient experience Nephrotoxicity (Scr increase >0.5 from baseline)? Yes No Non-antibiotic reasons for nephrotoxicity? Yes No Day of therapy nephrotoxicity occurred: days

9 Years NAME AGE Months GENDER Female Days Male MRN (check ONE) cm (ALL TCH pts) Adults IBW (male) = 50 + (2.3 X Height in inches over 5 feet) Height inches Ideal Body Weight: kg IBW (female) = (2.3 X Height in inches over 5 feet) [IBW is in kg] Children (1 to 18 years of age) IBW = Height 2 X 1.65 [IBW is in kg; Height is in cm] 1000 Actual Body Weight kg Dosing Body Weight kg DBW = 0.4 X [Actual body wt Ideal body wt] + Ideal body wt. [All wts are in kg] DOSING INFORMATION (Use separate sheet for each agent) DRUG NAME Start Date & Time of 1 st Dose Dosage Regimen (Dose/Route/Interval and Dose per kg in TCH) Sched Admin Times HOSPITAL COURSE / DISCUSSIONS WITH PRESCRIBERS Date & Time of Last Dose Loading Dose? No Yes IF Yes, Date and Time of Loading Dose Measured Cp (mcg/ml) Time Drawn Kelim (hr 1 ) T1/2elim (hrs) IF Yes: Dosage & Route Dose per body weight: mg/kg Calculated Recommendation Cp (mcg/ml) (New dose/route/interval; NC=No change,etc.) Vd (L/kg) Desired Peak (mcg/ml) Outcome (Accepted/ Rejected) Desired Trough (mcg/ml) RPh (Print 1 st Initial & full last name) DATE COMMENTS DATE COMMENTS

10 References: 1. Osterkamp, LK. Current Perspective on Assessment of Human Body Proportions of Relevance to Amputees. J Am Diet Assoc. 1995; 95(2): Rybak M, Lomaestro B, Rotschafer JC, et al. Therapeutic monitoring of vancomycin in adult patients: A consensus review of the American Society of Health-System Pharmacists, the Infectious Diseasses Society of America, and the Society of Infectious Diseases Pharmacists. Am J Health-Syst Pharm, 2009;66: Vandecastee SJ, Bacquer DD, Vriese AS. Implementation of a dose calculator for vancomycin to achieve target trough levels of ug/ml in persons undergoing hemodialysis. Clinical Infectious Diseases, 2011;53(2): Zelenitsky SA, Ariano, RE, McCrae ML, et al. Initial vancomycin dosing protocol to achieve therapeutic serum concentrations in patients undergoing hemodialysis. Clinical Infectious Diseases, 2012;55(4): Vancomycin HCL. Lexi-Drugs Online. Hudson, OH: Lexi-Comp, Inc. Updated December 5, Accessed December 10, 2014.