PTCB Practice Test 8

Explanation
The flowrate of the infusion pump is 167 ml/hr. This means that the pump will deliver 167 milliliters of D5W every hour through the intravenous (IV) route. The "q6h" in the order indicates that the infusion should be given every 6 hours. Therefore, the pump will deliver 167 ml of D5W every hour for a total of 6 hours, resulting in a flowrate of 167 ml/hr.

Explanation
The flow rate can be calculated by dividing the total volume (in drops) by the total time (in minutes). In this case, the total volume is 1L, which is equal to 1000ml. Since the drop factor is 15 gtt/ml, the total number of drops would be 1000ml x 15 gtt/ml = 15000 gtt. The total time is 8 hours, which is equal to 8 x 60 minutes = 480 minutes. Dividing the total number of drops by the total time gives us 15000 gtt / 480 min = 31.25 gtt/min. Rounding to the nearest whole number, the flow rate is 31 gtt/min.

Explanation
The question asks for the amount of Vancomycin in milligrams in a 1.25 gram per 250 ml IV solution. To convert grams to milligrams, we multiply by 1000. So, 1.25 grams is equal to 1250 milligrams. Therefore, the correct answer is 1250 mg.

Explanation
The prescription of Tussionex instructs the patient to take 2 teaspoons once daily as needed for cough for 6 days. Since the medication comes in a 12 oz bottle, and the patient is instructed to take it once daily, it can be inferred that the medication will last for 6 days.

Explanation
The ratio strength is a way to express the concentration of a solution. In this case, the concentration is 2g of active ingredient in 250 ml of solution. To express this as a ratio strength, we need to simplify the ratio of the amount of active ingredient to the volume of solution. By dividing both numbers by 2, we get 1g of active ingredient in 125 ml of solution. Therefore, the ratio strength is 1:125.

Explanation
The physician prescribes the patient to take 2 teaspoonfuls four times a day for 4 days, which amounts to 8 teaspoonfuls per day. Since there are 4 days, the total number of teaspoonfuls needed for this period is 8 x 4 = 32 teaspoonfuls.
After 4 days, the patient is instructed to take 1 teaspoonful four times a day for 2 days, which amounts to 4 teaspoonfuls per day. Since there are 2 days, the total number of teaspoonfuls needed for this period is 4 x 2 = 8 teaspoonfuls.
Therefore, the total number of teaspoonfuls needed for the entire dosage regimen is 32 + 8 = 40 teaspoonfuls.
Since 1 teaspoonful is equivalent to 5 ml, the total amount of suspension needed is 40 x 5 = 200 ml.

Explanation
To find the amount of 10% w/w ammonia solution that can be made, we need to determine the amount of ammonia present in the 28% w/w solution and then dilute it to a 10% w/w concentration.

First, we need to calculate the amount of ammonia in the 1800 g of 28% w/w solution. Since the solution is 28% w/w, it means that 28% of the solution is ammonia. Therefore, the amount of ammonia in the solution is 0.28 * 1800 g = 504 g.

Next, we need to dilute this 504 g of ammonia to a 10% w/w concentration. To do this, we divide the amount of ammonia by the desired concentration: 504 g / 0.10 = 5040 g.

Therefore, 5040 g of the 28% w/w ammonia solution can be used to make 10% w/w ammonia solution.

Explanation
To make a 1:2000 w/v solution, we need to dilute the stock solution. The ratio of the stock solution to the final solution is 1:2000. Since the stock solution is 1:400 w/v, we need to dilute it further. By cross-multiplying the ratios, we can find the volume of the stock solution needed. 1/400 = x/2000. Solving for x, we get x = 800 ml. Therefore, 800 ml of the stock solution should be used to make 4L of the 1:2000 w/v solution.

Explanation
When 250 ml of a 1:800 v/v solution is diluted to 1000 ml, the ratio strength v/v can be calculated by dividing the volume of the original solution by the total volume of the diluted solution. In this case, the original solution had a volume of 250 ml and the diluted solution had a volume of 1000 ml. Therefore, the ratio strength v/v is 1:3200, as the original solution was diluted by a factor of 4 (1000 ml / 250 ml = 4).

Explanation
The percentage of alcohol in the mixture can be calculated by finding the weighted average of the two percentages of alcohol. Since we have 5 ml of alcohol with 4% concentration and 10 ml of alcohol with 2% concentration, we can calculate the total amount of alcohol in the mixture as (5 ml * 4%) + (10 ml * 2%) = 0.2 ml + 0.2 ml = 0.4 ml.

The total volume of the mixture is 5 ml + 10 ml = 15 ml.

Therefore, the percentage of alcohol in the mixture is (0.4 ml / 15 ml) * 100% = 2.66%.

Explanation
Remember a % is always over 100
Hint: Reduce fraction

Explanation
The given question asks for the conversion of 2:00 pm into military time. In military time, the hours are represented on a 24-hour clock without the use of am or pm. To convert 2:00 pm into military time, we simply add 12 hours to the given time. Therefore, 2:00 pm becomes 14:00, which is represented as 1400 in military time.

Explanation
To find the amount of 5% dextrose solution and sterile water needed to fill the order, we can use the equation:

(amount of 5% solution) x (concentration of 5% solution) + (amount of sterile water) x (concentration of sterile water) = (order volume) x (order concentration)

Plugging in the given values, we get:

(amount of 5% solution) x (0.05) + (amount of sterile water) x (0) = (380 ml) x (0.005)

Simplifying the equation, we find that the amount of 5% dextrose solution needed is 38 ml, and the amount of sterile water needed is 342 ml.

Explanation
To calculate the amount of solution to be given to the patient, we first need to convert the weight of the patient from pounds to kilograms. Since 1 pound is approximately 0.45 kilograms, the patient weighs approximately 113.4 kg.

Next, we multiply the weight of the patient (113.4 kg) by the recommended dose (150 units/kg) to find the total dose needed.

113.4 kg x 150 units/kg = 17,010 units

Now, we divide the total dose needed (17,010 units) by the concentration of the solution (50,000 units/ml) to find the volume of the solution to be given.

17,010 units / 50,000 units/ml = 0.3402 ml

Rounding to the nearest tenth, the correct answer is 0.3 ml.

Explanation
The retail price for the prescription of 3 tablets is $69.25. This is calculated by first finding the cost of the tablets, which is the wholesale price of $15.70 per tablet multiplied by 3. This gives a total cost of $47.10 for the tablets. Then, the markup of 35% is applied to this cost, which is $47.10 multiplied by 0.35, resulting in a markup of $16.49. Finally, the dispensing fee of $5.66 is added to the cost and markup, giving a total retail price of $69.25.

Explanation
The patient injects 42 units of insulin in the morning (qam) and in the evening (qpm), which adds up to a total of 84 units per day. Since each vial contains 100 units/ml, the patient will need approximately 0.84 ml of insulin per day. With a 2-week vacation, the patient will require a total of 11.76 ml of insulin (0.84 ml/day x 14 days). As each vial contains 10 ml, the patient will need at least 2 vials to cover the entire vacation period.

Explanation
To make a 450g ointment in a 3:5:7 ratio, we need to divide the total weight proportionally. The sum of the ratio parts is 3+5+7=15. To find the amount of each drug, we divide the total weight by the sum of the ratio parts and multiply by the corresponding ratio. For the first drug (3 parts), we have (450/15) * 3 = 90g. For the second drug (5 parts), we have (450/15) * 5 = 150g. And for the third drug (7 parts), we have (450/15) * 7 = 210g. Therefore, the correct answer is 90g; 150g; 210g.

Explanation
To prepare a 2.5% cream, a combination of two creams with different concentrations is required. The 10% cream is more concentrated than the desired 2.5% cream, so a smaller amount of it is needed. On the other hand, the 0.5% cream is less concentrated, so a larger amount of it is needed. By using 25g of the 10% cream and 95g of the 0.5% cream, the resulting mixture will have a total weight of 120g and a concentration of 2.5%.

Explanation
Since Mr. Brown needs to take 250 mg of the drug once a day and the drug is available in 500 mg tablets, he would need to take half of a tablet each day. Since there are 30 days in a supply, he would need 15 tablets to cover the entire duration.

Explanation
The expression "XIX + VIII" represents the sum of the Roman numerals XIX (19) and VIII (8). When we add these two values together, we get 27. Therefore, the correct answer is 27.