Calculations IV

Question 1

What is the equation for BMI?

Answer 1

• (Weight [lbs] / Height [in]) x 703

703 converts to kg/m2

Question 2

What is consider normal BMI?

-

Answer 2

• 18.5 - 24.9

Question 3

Example Question 1

A male patient comes to the pharmacy and tells the pharmacist he is 6’7” tall and 250 pounds. His waist curcunference us 43 inches. Calculate his BMI. Round to the nearest whole number. Is the patient underweight, normal weight, overweight, or obese?

Answer 3

• 28 kg/m2
• Overweight

Question 4

Example Question 2

Caculate the BMI for a male who is 6’ tall and weighs 198 lbs. Round to the nearest whole number. Is the patient underweight, normal weight, overweight, or obese?

Answer 4

• 27 kg/m2
• Overweight

Question 5

What is actual or total body weight?

Answer 5

• The weight that is on the scale

Question 6

What is Ideal Body Weight and what is the equation for it?

Answer 6

• The weight for a “Healthy” Patient
• (Males) = 50 kg + (2.3)(height over 5 feet)
• (Females) = 45.5 kg + (2.3)(height over 5 feet)

Question 7

What is Adjusted Body Weight and what is the Equation for it>

Answer 7

• Used when the patient is obese or overweight
• AdjBW = IBW + 0.4 (TBW - IBW)

Question 8

If a patient is underweight, what weight should you use to dose mg/kg medications?

TBW < IBW

Answer 8

• TBW for ALL medications

Question 9

If a patient is normal weight, what weight should you used to dose mg/kg medications?

TBW = IBW

Answer 9

• IBW for MOST medications

Question 10

If a patient is obese, what weight should you use to dose mg/kg medications?

TBW > 120% of IBW

Answer 10

• IBW = aminophylline, theophyllin, acyclovir, levothyroxine
• TBW = LMWHs, UFH, Vanc
• AdjBW = Aminoglycosides

Question 11

Exampe Question 3

A famle patient is to recieve 5 mg/kg/day of theophylline. The patient is 5’7” and weights 243 pounds. Calculate the daily Theophylline dose the patient should receive.

Answer 11

• 308 mg/day

Question 12

Example Question 4

A 34 year old male (height 6’7”, wieght 287 pounds) is hospitalized after a motor vehicle accident. He develops a Pseudomanoas Aeruginosa infection. The physician orders tobramycin 2 mg/kg IV Q8H. Calculate the tobramycin dose. Round to the nearest 10 milligram

Answer 12

• 220 mg IV Q8H

Question 13

Example Question 5

A patient will receive 400 mg of a drug in a 250 mL IV bag. The rate of the drug administration is 375 mcg per minute. Calculate the flow rate in milliliters per hour. Round to the nearest whole number.

Answer 13

• 14 ml/hr

Question 14

Example Question 6

The pharmacist has an order for herparin 25,000 units in 250 ml D5W to infuse at 1000 units/hour. The pharmacy has the following premixed herpain bags in stock: 25000 units in 500 ml 1/2 NS, 10000 units in 250 ml D5W, and 25000 units in 250 ml D5W. What should the infusion rate be set at in ml/hour?

Answer 14

• 10 ml/hr

Question 15

Example Question 7

If 200 mg of drug are added to a 500 ml bag, what rate of flow, in milliliters per hour, will deliver 500 mcg of drug per hour? round to the nearest hundredth.

Answer 15

• 1.25 ml/hr

Question 16

Example Question 8

A nurse is hanging a 4% lidocaine drip for a patient. If the dose ordered is 6 mg/min, how many hours will a 250 ml bag last? round to the nearest whole number.

Answer 16

• 28 hours

Question 17

Example Question 9

A 68 kg patient is receiving a drug in a standard concentration of 400 mg/250 ml of 1/2 NS running at 15 ml/hr. Calculate the dose in mcg/kg/min. Round to the nearest hundredth

Answer 17

• 5.88 mcg/kg/min

Question 18

Example Question 10

The Pharmacist has an order for Heparin 25000 units in 250 ml D5W to infuse at 1000 units/hour. How many hours will it take to infuse the entire bag?

Answer 18

• 25 hours

Question 19

Example Question 11

If 50 mg of drug are added to a 500 ml bag, what rate of flow, in milliliters per hour, will the deliver 5 mg of drug per hour?

Answer 19

• 50 ml/hr

Question 20

Example Question 12

A patient is to receive Keppra at a rate of 5 mg/min. The pharmacy has 5 ml Keppra vial (100 mg/ml) which will be diluted in 100 ml of NS> What is the Keppra infusion rate, in mL/min? Do not include volmue of the 5 ml additive.

Answer 20

• 1 ml/min

Question 21

Example Question 13

A patient is to receive 600,000 units of penicillin G potassium in 100 ml D5W. A vial of Penicillin G potassium 1,000,000 units is available. The manufacturer state that when 4.6 ml of diluent is added, a 200,000 unit/ml solution will result. How many milliliters of reconsitiuted solution whould be withdrawn and added to the bag of D5W?

Answer 21

• 3 ml

Question 22

Example Question 14

A patient is to recevie Flagyl at a rate of 12.5 mg/min. The pharmacy has a 5 ml (100 mg/ml) Flagyl injection vial to be diluted in 100 ml of NS. How much drug in milligrams will the patient receive over 20 minutes.

Answer 22

• 250 mg`

Question 23

Example Question 15

A physician had ordered 2 grams of cefotetan to be added to 100 ml NS for a 56 year oid female with an anaerobic infection. Using a reconstituted injection containing 154 mg/ml, how many milliliters should be added to prepare the order? Round to the nearest whole number.

Answer 23

• 13 ml

Question 24

Example Question 16

JV is a 58 year old male hospitailed for a total knee replacement. He was given unfractionated heparin and deeloped heparin-induced thrombocytopenia (HIT). Argatroban was order at a dose of 2 mcg/kg/min. The pharmacy mixes a concentration of 100 mg argatroban in 250 ml of D5W. JV weights 187 lbs. At what rate (ml/hour) should the nurse infuse argatroban to provide the desired dose? round to the nearest whole number.

Answer 24

• 26 ml/hr

Question 25

# Example Question 17 A **165 pound** patient is to receive **250 ml** of a dopamine drip at a rate of **17 mcg/kg/min**. The pharmacy has dopamine premixed in a concentration of **3.2 mg/ml** in D5W. Calculate the infusion rate in **ml/minute**. Round to the nearest tenth.

Answer 25

- 0.4 ml/min

Question 26

# Example Question 18 An order is written for phenytion IV. A loading dose of **15 mg/kg** is to be infused at **0.5 mg/kg/min** for a **33 pound** child. The pharmacy has phenytoin injection solution **50 mg/ml** in a 5 ml vial in stock. The pharmacist will put the dose into 50 ml NS. Over how many **minutes** shuld the dose be administered? Round to the nearest whole number. ## Footnote **X**

Answer 26

- 30 mins

Question 27

# Example Question 19 A physician order an IV infusion of D5W **1 liter** to be delived over **8 hours**. The IN infusion set delivers **15 drops/ml**. How many **Drops/min** will the patient receive? Round to the neraest whole number

Answer 27

- 31 drops/min

Question 28

# Example Question 20 A phyisican orders **15 units** of regular insulin in **1 liter** of D5W to be given over **10 hours**. What is the infusion rate, in **drops/minute**, if the IV set delivers 15 drops/ml? Do not include the insulin volume in the calculation

Answer 28

- 25 drops/min

Question 29

# Example Question 22 An order is written for **10 ml of a 10% calcium chloride injection** and **10 ml of mulitvitamin injection (MBI)** to be added to **500 ml** of D5W. The infusion is to be administered over **6 hours**. The IV set delivers **15 drops/ml**. What should the rate of flow in **drops/minute** to deliver this infusion? Round to the nearest whole number.

Answer 29

- 22 drops/min

Question 30

# Example Question 21 The pharmacy has insulin vials containing **100 units** of insulin/ml. A physician orders **15 units** of regular insulin in **1 Liter** of D5W to be given over **10 hours**. How many **units** of insulin will the patient receive each hour if the IV set delivers **15 drops/ml**? Do not round the answer.

Answer 30

- 1.5 units/hour

Question 31

# Example Question 23 RS is a 45 year old male, **5'5", 168 pounds**, hospitalized witha. diabetic foot infection. The pharmacist has prepared a **500 ml** bag of D5W containing **1 gram** of vancomycin to be infused over **4 hours** using a **20 gtt/ml** IV tubing set. How many **milligrams** vancomycin will the patient receive each minute? Round to the nearest tenth.

Answer 31

- 4.2 mg/min

Question 32

# Example Question 24 A patient is to receive **1.5 liters** of NS running at **45 gtt/min** using a **15 gtt/ml** IV tubing set. Calculate the total infusion time in hours. Round to the nearest tenth.

Answer 32

- 8.3 hours

Question 33

# Example Question 25 The 8 AM nmedication scheduled for a patient include *Tygacil* dosed at **6 mg/kg**. The patient weight **142 pounds**. The nurse has *Tycagil* labeled **500 mg/50 ml** NS. The dose will be administered over **30 minutes**. The IV tubing in the unit delivers **15 drops per milliliter**. What is the correct rate of flow in **drops per minute**? Round to the nearest drop.

Answer 33

- 19 drops per minute x 30 minutes

Question 34

What is the **BUN:SCr Ratio** that shows if a patient is dehyrated or not?

Answer 34

- > 20:1

Question 35

# Example Question 26 Looking at the laboratory values below, make an assessment of the patient's hydration status. A) The patient appears to be well hydrated. B) The patient appears to be too hydrated. C) The patient is not experiencing dehydration D) The patient is experiencing dehydration E) The patient is experiecing fluid accumlation ## Footnote - BUN 54 mg/dL (Normal: 7 - 20) - SCr 1.8 mg/dL (Normal: 0.6 - 1.3)

Answer 35

- **D**

Question 36

# Example Question 27 NK is receiving a furosemie infusion at **5 mg/hr**. The nurse notices her urine output has decreased in the last hour. Laboratory values are drawn and the patient has a **SCr of 1.5 mg/dL** and a **BUN of 26 mg/dL**. The nurse wants to know if she should stop the furosemide infusion die to the patient becoming dehydrateed. What is the correct assessment of the patients hydration status. A) The patient appears to be too hydrated given the laboratory results B) The patient is not experiencing dehydration given the laboratory results C) The patient is experiencing dehydration and may need to be started on fluids D) The patient has objective information indicating dehydration byt the patient needs to be assessed subjectively as well E) None of the above

Answer 36

- **B**

Question 37

What is the **Cockcroft-Gault Equation**? ## Footnote **!!! IMPORTANT !!!**

Answer 37

- [(140 - (age)) / (72 x SCr)] x weight in kg ## Footnote **x 0.85 if female**

Question 38

What weight would you use for the Cockcroft-Gault Equation? ## Footnote Under, Normal, Over/Obese

Answer 38

- Underweight (TBW < IBW) = **TBW** - Normal (TBW = IBW) = **IBW** - Overweight/Obese (TBW > IBW) = BMI < 25 --> **IBW** OR BMI > 25 --> **AdjBW**

Question 39

# Example Question 28 A 64 year old female patient (**height 5'5", weight 205 pounds**) is hospitalized with a nosocomial pneumonia which is responding to treatment. Her cerrent antibiotic medications include ciprofloxican, *Primaxin*, and Vancomycin. Her morning laboratory values include **K 4 mEq/L, BUN 60 mg/dL, SCr 2.7 mg/dL and glucose 222 mg/dL**. Based on the renal dosage recommendations from the package label below, what is the correct dose of *Primaxin* for thos patient? ## Footnote Primaxin Dose - CrCl: > 90 --> 1000 mg IV q8h - CrCl: 60 - 89 --> 500 mg IV q6h - CrCl: 30 - 59 --> 500 mg IV q8h - CrCl: 15 - 29 --> 500 mg IV q12h

Answer 39

- 500 mg IV Q12H

Question 40

# Example Question 29 Levofloxacin, dosing per pharmacy, is order for an **87 year old female** (**height 5'4", weight 103 pounds**). Her labs include **BUN 22 mg/dL and SCr 1 mg/dL**. Choose the correct dosing regimen based on the renal dosing adjustment form the package labeling below> ## Footnote Levofloxacin Dose: - CrCl: > 50 -->500 mg Q24H - CrCl: 20 - 49 --> 250 mg Q24H - CrCl: < 20 --> 250 mg Q48H

Answer 40

- 250 mg Q24H

Question 41

# Example Question 30 A **50 year old** male (**height 6'1", weight 177 pounds**) has HIV and is being started on tenofovir disoproxil fumarate, emtricitabine and efavirenz therapy. His laboratory values include **K 4.4 mEq/L, BUN 40 mg/dL, SCr 1.8 mg/dL, and CD4 count of 455 cells/mm3**. Using the renal dosage recmmendations from the package labeling below, what is the correct dose of tenofovir for this patient? ## Footnote Tenofovir Dosing - CrCl: > 50 --> 300 mg daily - CrCl: 30 - 49 --> 300 mg Q48H - CrCl: 10 - 29 --> 300 mg Q72 - 96H - CrCl: < 10 --> 300 mg weekly

Answer 41

- 300 mg daily

Question 42

For acid-base, what do the **kidneys and lungs** do?

Answer 42

- Kidney controls **Bicarb** and the Lungs control **Carbon Dioxide**

Question 43

What is the way that you determine **acidosis vs alkalosis**?

Answer 43

- pH < 7.35 = Acidosis - pH > 7.45 = Alkalosis

Question 44

What is **Metabolic Acidosis**?

Answer 44

- Primarily **decrease** in Bicarb

Question 45

What is **Metabolic Alkalosis**?

Answer 45

- Primarily **Increased** in Bicarb

Question 46

what is **Respiratory Acidosis**?

Answer 46

- Primarly **Decreased** Carbon Dioxide

Question 47

What is **Respiratory Alkalosis**?

Answer 47

- Primarily **increase** in Carbon Dioxide

Question 48

What are the **ABG Parameters**? ## Footnote pH, pCO2, pO2, HCO3, O2 Stat

Answer 48

- **pH: 7.35 - 7.45** - **pCO2: 35 - 45** - pO2: 80 - 100 - **HCO3: 22 - 26** - O2 Stat: > 95%

Question 49

# Example Question 31 A baby sitter brings a **7 year old** boy to the emergency department. He is unarousable. Labs are orders and an ABG is drawn. The ABG results are as follows **6.72/40/89/12/94%**. What Acid-Base disorder dose the child have? ## Footnote pH/pCO2/pO2/HCO3/O2 Stat

Answer 49

- Metabolic Acidosis

Question 50

# Example Question 32 An elderly female is admitted to the hospital after a motor vehicle accident. She suffered a head injury and is in the ICU. An ABG is obtained and the results are as follows: **8.25/29/97/26/98%**. What acid-base diorder dose the patient have? ## Footnote pH/pCO2/pO2/HCO3/O2 Stat

Answer 50

- Respiratory Alkalosis

Question 51

When is **anion gap** calculated and what is the **equation** for it?

Answer 51

- During **metabolic acidosis** - AG = Na - Cl - HCO3

Question 52

What are some of the **causes** for **gap acidosis**? ## Footnote **CUTE DIMPLES**

Answer 52

- **C**yanide - **U**remia - **T**oluene - **E**thanol (alcoholic Ketoacidosis) - **D**iabetic Ketoacidosis - **I**soniazid - **M**ethanol - **P**ropylene Glycol - **L**actic Acidosis - **E**thylene Glycol - **S**alicylates

Question 53

# Example Question 33 A patient in the ICU has recently developed an acidosis. Using the laboratory parameters below, calculate the patients anion gap. ## Footnote - Na 139 - Cl 101 - K 4.6 - HCO3 19 - SCr 1.6 - BUN 38

Answer 53

- 19 = gap acidosis