Formula
Content
Formula dose ordered x volume available dose available Actually this is the same formula used in the "PO dosage calculator." Examples 1) Dr. Smith has ordered a heparin infusion of 1000 units/hour for John Doe in bed 7. The infusion is to be mixed as 25,000 units in 500 mL .9% NS. What rate will the IV pump be set to? In this example, 1000 units/hr = dose ordered 25,000 units = dose available 500 mL = volume available 1,000units 25,000unit s x 500mL
which = 20 mL So the volume to give, an infusion, = 20 mL/hour 2) Give 40mg of Lasix® (furosemide) IVP. The vial of furosemide contains 100 mg per 10 mL. In the example, 40 mg = dose ordered 100 mg = dose available 10 mL = volume available 40mg x 10mL 100mg which = 4 mL So the volume to give, a 1x dose, = 4 mL TO CALCULATE RATE USING MINUTES
volume x calibration minutes
= gtt/min
TO CALCULATE RATE USING HOURS
volume x calibration hours x 60
= gtt/min
Examples 1) Give a 50cc IVPB over 30 minutes using IV tubing with a calibration of 10. How many drops per minute should this IVPB be set for? See the example below. select "x = minutes" x = 30 volume = 50 calibration = 10 Actual formula:
50 x 10 30
= 16.7 or 17 gtt/min
2) Using IV tubing alone (calibrated at 60), prepare an IV to infuse 1 liter over 8 hours. How many drops per minute should the IV be set for? See the example below. select "x = hours" x=8 volume = 1000 calibration = 60 Actual formula:
1000ml x 60 8 x 60
= 125 gtt/min
Note, when using microdrip tubing (calibration = 60), the drip rate will be the same as mL/hr. This will save you the time of calculating the drip rate if asked to give the rate in mL/hr. 3) The doctor orders an IV to infuse at 125cc/hr. Calculate the flow rate using 10 drop/min IV tubing. select "x = milliters/hour" x = 125 calibration = 10 Actual formula:
125cc x 10 = 20.8 or 21 gtt/min 60
Note You may be wondering why a second answer is displayed in the calculator. The first answer displays the number of drops per minute. The second answer displays how many drops fall in 15 seconds. Sometimes the IV rate is set by counting for 15 seconds instead of a full minute.
calculate rate based on time
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time = hours time = minutes time volume mL rate mL/hour
Examples 1) If an order was written to infuse a liter of IV fluid every 8 hours, at what rate would the IV pump be set for? Answer is 125 mL/hour. Using the calculator, select the time to equal hours (it's already preselected). Next enter 8 as the value for time (8 hours). Enter 1000 mL (1 L = 1000 mL) as the volume to be infused. Click the "solve" button which calculates the result as 125 mL/hour. See the example below.
2) You have recieved a new admission from the E.R. The patient has class IV CHF and the doctor has ordered a loading dose of Inocor®(amrinone lactate). The loading dose is to be administered over 3 minutes. Pharmacy has brought the loading dose as a 50 mL IVPB. At what rate should the IVPB be infused? Answer is 1000 mL/hour. Using the calculator, select time to equal minutes. Next, enter 3 as the value for time (3 minutes). Enter 50 as the volume to be infused. Click the "solve" button which calculates the result as 1000 mL/hour. See the example below.
Formulas TO CALCULATE RATE USING HOURS
VOLUME HOURS
= mL/hr
TO CALCULATE RATE USING MINUTES
VOLUME (MINUTES / 60)
nursing calculators
= mL/hr
convert mcg/min to ml/hr
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dose ordered (mcg) dose available (mg) mL available rate (mL/hr)
Example Start an infusion of nitroglycerin at 10 mcg/min, then titrate to chest pain. The nitroglycerin is to be mixed as 50 mg in 250cc of D5W. Use the example below to see how to plug the numbers into the calculator.
In this example, the nitroglycerine infusion will be set to 3 mL/hr. Formula First, convert mcg/min to mg/hr. For example, 10 mcg/min becomes 0.6 mg/hr.
Next, solve the rest by using the IV dosage formula. In the example given, 0.6mg is the dose ordered, 50 mg is the dose available, and 250 mL is the volume available.
If you're lucky enough to have new IV pumps that accept mcg/min, obviously this entire process is unnecessary.
convert mcg/kg/min to ml/hr
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dose ordered (mcg) weight (kg or lbs) dose available (mg) mL available
rate (cc/hr)
Example Dr. Smith wants a dopamine drip started at 20mcg/kg/min on John Doe in Bed 7. John Doe's weight is 70 kilograms. He wants an 800mg vial of dopamine mixed in 500 mL of D5W. Plug in the amounts in the calculator as shown below.
Click the box to enter weights in pounds
Using the calculator, John Doe's IV pump is set to deliver 53 cc/hr of Dopamine. Formula (mcg x kg) 1000 X 60
First, convert mcg/kg/min into mg/hr. In the example above, the dose would be 84 mg/hr.
(20mcg x 70kg) X 60 = 84 1000
Next, use the IV dosage formula to solve the rest of the problem. dose ordered X volume dose availableavailable In the example, 84 mg is the dose ordered, 800 mg is the dose available, 500 mL is the volume.
84mg X 500ml = 52.5 ml/hr 800mg
If you're lucky enough to have new IV pumps that accept mcg/kg/min, obviously this entire process is unnecessary.
IV infusion time
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IV pump No IV pump enter volume enter ml/hr enter gtts/min enter IV calibration hours minutes
Formulas Basic Time
Volume = Hours Rate
Time Calculated Using IV Tubing Only
Volume /
(
gtt/min x 60 Calibration
)
= Hours
Examples 1. Using a volumetric IV pump calculate to duration of 1000 mL of normal saline infusing at 125mL/hour. select "IV pump" volume = 1000 milliliters rate = 125 mL/hr Actual formula:
1000mL = 8 Hours 125
2. There are 250 mL of D5W infusing at 33 gtt/min on IV tubing calibrated at 10 gtt/mL. Calculate the infusion time. select "No IV pump" volume = 250 mL rate = 33 gtt/min calibration = 10 gtt/mL Actual formula:
250 /
(
33 gtt/min x 60 10
)
= 1.26 Hours
0.26 x 60 = 16 minutes So 1.26 Hours = 1 Hour & 16 minutes
convert mL/hr to dose/hr
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rate or volume given dose available volume available dose ordered
Example You have received report on a patient with a heparin drip but the nurse forgot to say what dosage the drip was infusing at. The heparin bag is labeled 25,000 units in 250 mL NS and the IV pump is infusing at 20 mL/hr. In this example, 20 mL/hr = rate, an infusion. 25,000 units = dosage available 250 mL = volume available So the dosage ordered, an infusion, = 2000 units/hour See the example below.
Formula rate x dose available mL available Using the formula on the example above looks like this:
20cc/hr x 25,000units 250mL
which = 2000 units/hr It doesn't matter if you use milligrams or units or something else in the formula.
convert mL/hr to mcg/min
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IV rate mL/hr dose available mL available mcg/min
Example A patient is on a norepinephrine drip infusing at 56 cc/hr. There is no titration table table at the bedside. The IV bag is labeled 32 mg norepinephrine in 500cc Dextrose 5%. How many mcg/min is the patient receiving? Use the example below to see how to solve this problem with the calculator. rate = 56mL/hr dose available = 32mg mL available = 500mL
With the calculator, we see the patient is recieving 60 mcg/min of norepinephrine. This is a higher than recommended dose!!! Formula In this example, first determine how many milligrams/hour is being delivered by the IV pump. The rate of the IV pump (mL/hr) is divided by the volume of the IV bag (mL available), then multiply this result by the total amount of medication (mg) in the IV bag. rate x dose available mL available becomes
56mL/hr x 32mg 500mL
which = 3.58 mg/hr Next, after the milligrams/hour has been determined, use the next formula to convert from milligrams/hour to mcg/min. mg x 60min 1000 becomes
3.58mg x 1000 60min
which is 59.7 mcg/min (yikes!)
convert mL/hr to mcg/kg/min
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IV rate cc/hr weight (kg) dose available mL available
mcg/kg/min
Example You have received a patient from another hospital on a dopamine drip except no information was given about it. The bag is labeled with the concentration of 800 mg in 500cc of D5W. The IV pump is infusing at 53 cc/hr and the patient weighs 70kg. How much dopamine is this patient receiving? Use the example below to see how this problem was solved. rate = 53mL/hr weight = 70kg dose available = 800 ml available = 500
Using the calculator, we know the patient is receiving 20 mcg/kg/min of dopamine. Formula Using the example above, first determine how many milligrams/hour is being delivered by the IV pump. The rate of the IV (cc/hr) is divided by the volume of the IV bag (mL available), then multiply this result by the total amount of medication (mg) in the IV bag. rate x dose available mL available becomes
53mL/hr x 800mg 500mL
which = 84.8 mg/hr Next, after the milligrams/hour has been determined, use the next formula to convert from milligrams/hour to mcg/kg/min. mg x 1000 / 60min kg becomes
84.8mg x 1000 / 70 60min
which = 20.2 mcg/kg/min
pediatric dose calculator
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Read First!
weight (kg) height (cm) adult dose child dose
I want to use a nomogram to determine BSA Example The doctor has ordered an antibiotic whose average adult dose is 250 mg per day. What would the dosage for this medication be on a child who is 100 cm in length and weighs 25 kg? See the example below.
In this example, 115 mg of medication would be given. Formula First, the body surface area (BSA) must be determined: kg0.425 x cm0.725 x 0.007184 = BSA
The above formula is just one method for determining BSA. Results with other formulas will vary.
Next, the following formula* is used: BSA x adult dose = approx. child 1.73 dose
IVF replacement for NPO deficit
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weight kg hours NPO mL 1st hr mL 2nd hr mL 3rd hr
Example What is the NPO deficit for a patient who weighs 50 kg who has been NPO for 10 hours prior to surgery? The answer is 1 liter (500 mL 1st hour, 250 mL 2nd hour, and 250 mL 3rd hour). See how the numbers were used on the calculator below.
Formula IV fluid replacement for NPO deficit = 2mL/kg for each hour NPO prior to surgery. 50% of this deficit is replaced within the first hour of surgery with the remaining 50% being replaced over the next 2 hours. If the patient stayed in the hospital overnight with an IV infusing while NPO, subtract this amount from the NPO deficit. In the example above: 2 mL/kg/hr = 2 x 50 x 10 = 1000 @1st hr, 500 mL will be replaced 2nd hr, 250 mL will be replaced 3rd hr, 2hr 250 mL will be replaced If in this example, the patient stayed in the hospital overnight with an IV infusion at 100 mL/hr while NPO, all their NPO deficit (1 liter) would already be replaced.
BW & ABW calculator
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male female weight height
IBW IBW + 30% ABW
Formula
IBW Estimated ideal body weight in (kg) Males: IBW = 50 kg + 2.3 kg for each inch over 5 feet. Females: IBW = 45.5 kg + 2.3 kg for each inch over 5 feet. ABW Estimated adjusted body weight (kg) If the actual body weight is greater than 30% of the calculated IBW, calculate the adjusted body weight (ABW): ABW = IBW + 0.4(actual weight - IBW) The IBW and ABW are used to calculate medication dosages when the patient is obese. This formula only applies to persons 60 inches (152 cm) or taller. If calculating by hand use formula as shown (inches & kilograms). Formulas referenced from GlobalRPH.
Examples
Example 1 Calculate the ideal body weight (IBW) of a man who is 64 inches tall and weighs 70 kilograms. If this man is obese (> IBW + 30%), calculate the adjusted body weight. To solve the example using the calculator, select the radio button for male. Next, enter the height (inches) and weight (kilograms): weight = 70 kg height = 64 inches IBW = 59.2
Or solve using formula: IBW = 50 kg + 2.3 x each inch over 5 feet (60inches) IBW = 50 kg + 2.3 x 4 inches IBW = 50 kg + 9.2 IBW = 59.2 kg The man's actual weight is less than IBW + 30% so it is not necessary to calculate the adjusted body weight (ABW). Example 2 Calculate the ideal body weight (IBW) of a woman who is 64 inches tall and weighs 80 kilograms. If this woman is obese (> IBW + 30%), calculate the adjusted body weight. To solve the example using the calculator, select the radio button for female. Next, enter the height (inches) and weight (kilograms): weight = 80 kg height = 64 inches IBW = 54.7 Or solve using formula: IBW = 45.5 kg + 2.3 x each inch over 5 feet (60inches) IBW = 45.5 kg + 2.3 x 4 inches IBW = 45.5 kg + 9.2 IBW = 54.7 kg The woman's actual weight is greater than the IBW + 30%, so calculate the ABW: ABW = 54.7 kg + 0.4( 80kg - 54.7 kg) ABW = 54.7 kg + 0.4( 25.3 kg ) ABW = 54.7 kg + 10.1kg ABW = 64.8 kg
abg interpreter
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pH CO2
HCO3
Normal Arterial Blood Gas Values
pH PaCO2 PaO2 HCO3 O2 Saturation BE 7.35-7.45 35-45 mm Hg 80-95 mm Hg 22-26 mEq/L 95-99% +/- 1
Four-Step Guide to ABG Analysis 1. Is the pH normal, acidotic or alkalotic? 2. Are the pCO2 or HCO3 abnormal? Which one appears to influence the pH? 3. If both the pCO2 and HCO3 are abnormal, the one which deviates most from the norm is most likely causing an abnormal pH. 4. Check the pO2. Is the patient hypoxic? I used Swearingen's handbook (1990) to base the results of this calculator. The book makes the distinction between acute and chronic disorders based on symptoms from identical ABGs. This calculator only differentiates between acute (pH abnormal) and compensated (pH normal). Compensation can be seen when both the PCO2 and HCO3 rise or fall together to maintain a normal pH. Part compensation occurs when the PCO2 and HCO3 rise or fall together but the pH remains abnormal. This indicates a compensatory mechanism attempted to restore a normal pH. I have not put exact limits into the calculator. For example, it will perceive respiratory acidosis as any pH < 7.35 and any CO2 > 45 (i.e. a pH of 1 and CO2 of 1000). These results do not naturally occur.
pH Respiratory Acidosis Acute Partly Compensated Compensated Respiratory PaCO2 HCO3
< 7.35 < 7.35 Normal
> 45 > 45 > 45
Normal > 26 > 26
Alkalosis Acute Partly Compensated Compensated Metabolic Acidosis Acute Partly Compensated Compensated Metabolic Alkalosis Acute Partly Compensated Compensated
> 7.45 > 7.45 Normal
< 35 < 35 < 35
Normal < 22 < 22
< 7.35 < 7.35 Normal
Normal < 35 < 35
< 22 < 22 < 22
> 7.45 > 7.45 Normal
Normal > 45 > 45
> 26 > 26 > 26
Mixed Disorders It's possible to have more than one disorder influencing blood gas values. For example ABG's with an alkalemic pH may exhibit respiratory acidosis and metabolic alkalosis. These disorders are termed complex acid-base or mixed disorders. *This table is able to classify most clinical blood gas values but not all. In cases where blood gas values do not fall into any of the above classifications, an answer "unable to determine" will appear when using the interpreter. For example a pH of 7.428, pCO2 43.6, and a HCO3 of 29.1 do not match any of the classifications (I found these results in someone's chart). While the pH and pCO2 are normal, the HCO3 is abnormally high.
convert fahrenheit & celsius
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enter temperature convert to Fahrenheit convert to Celsius result solution
Directions
Enter temperature to be converted in degrees Fahrenheit (°F) or Celsius (°C aka centigrade) in box. Select either Fahrenheit or Celsius button to perform conversion. Press "convert" button to display result at bottom.
Formula
°C x 9/5 + 32 = °F (°F - 32) x 5/9 = °C
Examples
1) Convert 37°C to Fahrenheit. 37°C x 9/5 + 32 = 98.6°F OR
37°C x 9 + 32 = 98.6°F 5
2) Convert 98.6°F to Celsius. (98.6°F - 32) x 5/9 = 37°C OR
(98.6°F - 32) x 5 = 37°C 9
Formulae
cm x 0.39* = in in 1 = ft 2 in x 2.54 = cm
Examples
If a woman is 5 foot, 3 inches (5' 3"), what is her height in centimeters?
(5' x 12) + 3" = 63" 63" x 2.54 = 160 cm
If a woman is 5 foot, 8 inches (5' 8"), what is her height in centimeters? (5' x 12) + 8" = 68" 68" x 2.54 = 172.7 cm If a man is 203.2 centimeters tall, what is his height in feet and inches? 203.2 cm x 0.3937008 = 80"
80 = 6.67' 12
.67 x 12 = 8.04 remainder
80 = 6 ft and remainder = 8 in 12
OR
6' 8"
Dosage By Weight Questions Given the weight of a patient and a dosage specified in terms of weight, calculate the necessary dosage. These problems are a type of pediatric dosage calculations.
Formula: Weight in Kg * Dosage Per Kg = Y (Required Dosage)
Example: A doctor orders 200 mg of Rocephin to be taken by a 15.4 lbinfant every 8 hours. The medication label shows that 75-150 mg/kg per day is the appropriate dosage range. Is this doctor's order within the desired range? Weight in Kg * Dosage Per Kg Convert 15.4 lb to kg.
•
= Y (Required Dosage)
lb → kg
( ÷ by 2.2 )
• 15.4 lb ÷ 2.2 = 7 kg 7 kg * 75 = 525 mg (Minimum Desired mg/kg Dosage)
7 kg * 150 mg/kg
= 1,050 mg (Maximum Desired Dosage)
24 hours in one day and the medication is ordered every 8 hours.
• • •
24 hrs / 8 hrs = 3 times per day doctor ordered medication 200 * 3 = 600 mg ordered per day 600 mg is within the desired range of 525-1,050 mg
Yes doctor has ordered a dosage within the desired range.
Example: Solumedrol 1.5 mg/kg is ordered for a child weighing 74.8 lb. Solumedrol is available as 125 mg / 2mL. How many mL must the nurse administer? Weight in Kg * Dosage Per Kg Convert 74.8 lb to kg.
• •
= Y (Required Dosage)
lb → kg
( ÷ by 2.2 )
74.8 lb ÷ 2.2 = 34 kg 34 kg * 1.5 = 51 mg/kg mg
•
This is now an ordinary Mass/Liquid For Liquid Question. 51 mg is ordered
and the medication is available as 125 mg / 2 mL. Ordere x Volume Per = Y (Liquid d Have Required) Have
51 mg 125 mg
x2 mL
= 0.82 mL
Fluid Maintenance Requirement Questions Given the weight of a child or infant, calculate the necessary amount of fluid per day. Different hospitals may have different policies, but for learning how to perform these pediatric dosage calculations, the following commonly used table of fluid requirements may be used. Weight Range 0-10 kg 10-20 kg 20-70 kg Over 70 kg Required Daily Fluid 100 mL per kg 1,000 mL + 50 mL per each kg above 10 kg 1,500 mL + 20 mL per each kg above 20 kg 2,500 mL (adult requirement)
Example: An infant weighs 4 kg. What is the required amount of fluid per day in mL? 0-10 kg
•
100 mL per kg
4 kg x 100 mL/kg = 400 mL
Example: An infant weighs 30.8 lb. What is the required IV flow rate in mL/hr to maintain proper fluid levels? Convert 30.8 lb to kg.
• •
lb → kg
( ÷ by 2.2 )
30.8 lb ÷ 2.2 = 14 kg 10-20 kg 1,000 mL + 50 mL per each kg above 10kg
•
14 kg - 10 kg = 4 kg (There are 4 kg over 10 kg).
• •
1,000 mL + (50 mL/kg x 4 kg) = 1,200 mL/day This is now an ordinary IV Flow Rate - mL Rate Question. The required
volume is 1,200 mL and the time is one day. Volume = Y (Flow Rate in (mL) mL/hr) Time (hr) There are 24 hours in one day. 1 day x 24 = 24 hr 1,200 = 50 mL mL/hr 24 hr
•
which = 20 mL So the volume to give, an infusion, = 20 mL/hour 2) Give 40mg of Lasix® (furosemide) IVP. The vial of furosemide contains 100 mg per 10 mL. In the example, 40 mg = dose ordered 100 mg = dose available 10 mL = volume available 40mg x 10mL 100mg which = 4 mL So the volume to give, a 1x dose, = 4 mL TO CALCULATE RATE USING MINUTES
volume x calibration minutes
= gtt/min
TO CALCULATE RATE USING HOURS
volume x calibration hours x 60
= gtt/min
Examples 1) Give a 50cc IVPB over 30 minutes using IV tubing with a calibration of 10. How many drops per minute should this IVPB be set for? See the example below. select "x = minutes" x = 30 volume = 50 calibration = 10 Actual formula:
50 x 10 30
= 16.7 or 17 gtt/min
2) Using IV tubing alone (calibrated at 60), prepare an IV to infuse 1 liter over 8 hours. How many drops per minute should the IV be set for? See the example below. select "x = hours" x=8 volume = 1000 calibration = 60 Actual formula:
1000ml x 60 8 x 60
= 125 gtt/min
Note, when using microdrip tubing (calibration = 60), the drip rate will be the same as mL/hr. This will save you the time of calculating the drip rate if asked to give the rate in mL/hr. 3) The doctor orders an IV to infuse at 125cc/hr. Calculate the flow rate using 10 drop/min IV tubing. select "x = milliters/hour" x = 125 calibration = 10 Actual formula:
125cc x 10 = 20.8 or 21 gtt/min 60
Note You may be wondering why a second answer is displayed in the calculator. The first answer displays the number of drops per minute. The second answer displays how many drops fall in 15 seconds. Sometimes the IV rate is set by counting for 15 seconds instead of a full minute.
calculate rate based on time
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time = hours time = minutes time volume mL rate mL/hour
Examples 1) If an order was written to infuse a liter of IV fluid every 8 hours, at what rate would the IV pump be set for? Answer is 125 mL/hour. Using the calculator, select the time to equal hours (it's already preselected). Next enter 8 as the value for time (8 hours). Enter 1000 mL (1 L = 1000 mL) as the volume to be infused. Click the "solve" button which calculates the result as 125 mL/hour. See the example below.
2) You have recieved a new admission from the E.R. The patient has class IV CHF and the doctor has ordered a loading dose of Inocor®(amrinone lactate). The loading dose is to be administered over 3 minutes. Pharmacy has brought the loading dose as a 50 mL IVPB. At what rate should the IVPB be infused? Answer is 1000 mL/hour. Using the calculator, select time to equal minutes. Next, enter 3 as the value for time (3 minutes). Enter 50 as the volume to be infused. Click the "solve" button which calculates the result as 1000 mL/hour. See the example below.
Formulas TO CALCULATE RATE USING HOURS
VOLUME HOURS
= mL/hr
TO CALCULATE RATE USING MINUTES
VOLUME (MINUTES / 60)
nursing calculators
= mL/hr
convert mcg/min to ml/hr
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dose ordered (mcg) dose available (mg) mL available rate (mL/hr)
Example Start an infusion of nitroglycerin at 10 mcg/min, then titrate to chest pain. The nitroglycerin is to be mixed as 50 mg in 250cc of D5W. Use the example below to see how to plug the numbers into the calculator.
In this example, the nitroglycerine infusion will be set to 3 mL/hr. Formula First, convert mcg/min to mg/hr. For example, 10 mcg/min becomes 0.6 mg/hr.
Next, solve the rest by using the IV dosage formula. In the example given, 0.6mg is the dose ordered, 50 mg is the dose available, and 250 mL is the volume available.
If you're lucky enough to have new IV pumps that accept mcg/min, obviously this entire process is unnecessary.
convert mcg/kg/min to ml/hr
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dose ordered (mcg) weight (kg or lbs) dose available (mg) mL available
rate (cc/hr)
Example Dr. Smith wants a dopamine drip started at 20mcg/kg/min on John Doe in Bed 7. John Doe's weight is 70 kilograms. He wants an 800mg vial of dopamine mixed in 500 mL of D5W. Plug in the amounts in the calculator as shown below.
Click the box to enter weights in pounds
Using the calculator, John Doe's IV pump is set to deliver 53 cc/hr of Dopamine. Formula (mcg x kg) 1000 X 60
First, convert mcg/kg/min into mg/hr. In the example above, the dose would be 84 mg/hr.
(20mcg x 70kg) X 60 = 84 1000
Next, use the IV dosage formula to solve the rest of the problem. dose ordered X volume dose availableavailable In the example, 84 mg is the dose ordered, 800 mg is the dose available, 500 mL is the volume.
84mg X 500ml = 52.5 ml/hr 800mg
If you're lucky enough to have new IV pumps that accept mcg/kg/min, obviously this entire process is unnecessary.
IV infusion time
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IV pump No IV pump enter volume enter ml/hr enter gtts/min enter IV calibration hours minutes
Formulas Basic Time
Volume = Hours Rate
Time Calculated Using IV Tubing Only
Volume /
(
gtt/min x 60 Calibration
)
= Hours
Examples 1. Using a volumetric IV pump calculate to duration of 1000 mL of normal saline infusing at 125mL/hour. select "IV pump" volume = 1000 milliliters rate = 125 mL/hr Actual formula:
1000mL = 8 Hours 125
2. There are 250 mL of D5W infusing at 33 gtt/min on IV tubing calibrated at 10 gtt/mL. Calculate the infusion time. select "No IV pump" volume = 250 mL rate = 33 gtt/min calibration = 10 gtt/mL Actual formula:
250 /
(
33 gtt/min x 60 10
)
= 1.26 Hours
0.26 x 60 = 16 minutes So 1.26 Hours = 1 Hour & 16 minutes
convert mL/hr to dose/hr
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rate or volume given dose available volume available dose ordered
Example You have received report on a patient with a heparin drip but the nurse forgot to say what dosage the drip was infusing at. The heparin bag is labeled 25,000 units in 250 mL NS and the IV pump is infusing at 20 mL/hr. In this example, 20 mL/hr = rate, an infusion. 25,000 units = dosage available 250 mL = volume available So the dosage ordered, an infusion, = 2000 units/hour See the example below.
Formula rate x dose available mL available Using the formula on the example above looks like this:
20cc/hr x 25,000units 250mL
which = 2000 units/hr It doesn't matter if you use milligrams or units or something else in the formula.
convert mL/hr to mcg/min
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IV rate mL/hr dose available mL available mcg/min
Example A patient is on a norepinephrine drip infusing at 56 cc/hr. There is no titration table table at the bedside. The IV bag is labeled 32 mg norepinephrine in 500cc Dextrose 5%. How many mcg/min is the patient receiving? Use the example below to see how to solve this problem with the calculator. rate = 56mL/hr dose available = 32mg mL available = 500mL
With the calculator, we see the patient is recieving 60 mcg/min of norepinephrine. This is a higher than recommended dose!!! Formula In this example, first determine how many milligrams/hour is being delivered by the IV pump. The rate of the IV pump (mL/hr) is divided by the volume of the IV bag (mL available), then multiply this result by the total amount of medication (mg) in the IV bag. rate x dose available mL available becomes
56mL/hr x 32mg 500mL
which = 3.58 mg/hr Next, after the milligrams/hour has been determined, use the next formula to convert from milligrams/hour to mcg/min. mg x 60min 1000 becomes
3.58mg x 1000 60min
which is 59.7 mcg/min (yikes!)
convert mL/hr to mcg/kg/min
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IV rate cc/hr weight (kg) dose available mL available
mcg/kg/min
Example You have received a patient from another hospital on a dopamine drip except no information was given about it. The bag is labeled with the concentration of 800 mg in 500cc of D5W. The IV pump is infusing at 53 cc/hr and the patient weighs 70kg. How much dopamine is this patient receiving? Use the example below to see how this problem was solved. rate = 53mL/hr weight = 70kg dose available = 800 ml available = 500
Using the calculator, we know the patient is receiving 20 mcg/kg/min of dopamine. Formula Using the example above, first determine how many milligrams/hour is being delivered by the IV pump. The rate of the IV (cc/hr) is divided by the volume of the IV bag (mL available), then multiply this result by the total amount of medication (mg) in the IV bag. rate x dose available mL available becomes
53mL/hr x 800mg 500mL
which = 84.8 mg/hr Next, after the milligrams/hour has been determined, use the next formula to convert from milligrams/hour to mcg/kg/min. mg x 1000 / 60min kg becomes
84.8mg x 1000 / 70 60min
which = 20.2 mcg/kg/min
pediatric dose calculator
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Read First!
weight (kg) height (cm) adult dose child dose
I want to use a nomogram to determine BSA Example The doctor has ordered an antibiotic whose average adult dose is 250 mg per day. What would the dosage for this medication be on a child who is 100 cm in length and weighs 25 kg? See the example below.
In this example, 115 mg of medication would be given. Formula First, the body surface area (BSA) must be determined: kg0.425 x cm0.725 x 0.007184 = BSA
The above formula is just one method for determining BSA. Results with other formulas will vary.
Next, the following formula* is used: BSA x adult dose = approx. child 1.73 dose
IVF replacement for NPO deficit
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weight kg hours NPO mL 1st hr mL 2nd hr mL 3rd hr
Example What is the NPO deficit for a patient who weighs 50 kg who has been NPO for 10 hours prior to surgery? The answer is 1 liter (500 mL 1st hour, 250 mL 2nd hour, and 250 mL 3rd hour). See how the numbers were used on the calculator below.
Formula IV fluid replacement for NPO deficit = 2mL/kg for each hour NPO prior to surgery. 50% of this deficit is replaced within the first hour of surgery with the remaining 50% being replaced over the next 2 hours. If the patient stayed in the hospital overnight with an IV infusing while NPO, subtract this amount from the NPO deficit. In the example above: 2 mL/kg/hr = 2 x 50 x 10 = 1000 @1st hr, 500 mL will be replaced 2nd hr, 250 mL will be replaced 3rd hr, 2hr 250 mL will be replaced If in this example, the patient stayed in the hospital overnight with an IV infusion at 100 mL/hr while NPO, all their NPO deficit (1 liter) would already be replaced.
BW & ABW calculator
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male female weight height
IBW IBW + 30% ABW
Formula
IBW Estimated ideal body weight in (kg) Males: IBW = 50 kg + 2.3 kg for each inch over 5 feet. Females: IBW = 45.5 kg + 2.3 kg for each inch over 5 feet. ABW Estimated adjusted body weight (kg) If the actual body weight is greater than 30% of the calculated IBW, calculate the adjusted body weight (ABW): ABW = IBW + 0.4(actual weight - IBW) The IBW and ABW are used to calculate medication dosages when the patient is obese. This formula only applies to persons 60 inches (152 cm) or taller. If calculating by hand use formula as shown (inches & kilograms). Formulas referenced from GlobalRPH.
Examples
Example 1 Calculate the ideal body weight (IBW) of a man who is 64 inches tall and weighs 70 kilograms. If this man is obese (> IBW + 30%), calculate the adjusted body weight. To solve the example using the calculator, select the radio button for male. Next, enter the height (inches) and weight (kilograms): weight = 70 kg height = 64 inches IBW = 59.2
Or solve using formula: IBW = 50 kg + 2.3 x each inch over 5 feet (60inches) IBW = 50 kg + 2.3 x 4 inches IBW = 50 kg + 9.2 IBW = 59.2 kg The man's actual weight is less than IBW + 30% so it is not necessary to calculate the adjusted body weight (ABW). Example 2 Calculate the ideal body weight (IBW) of a woman who is 64 inches tall and weighs 80 kilograms. If this woman is obese (> IBW + 30%), calculate the adjusted body weight. To solve the example using the calculator, select the radio button for female. Next, enter the height (inches) and weight (kilograms): weight = 80 kg height = 64 inches IBW = 54.7 Or solve using formula: IBW = 45.5 kg + 2.3 x each inch over 5 feet (60inches) IBW = 45.5 kg + 2.3 x 4 inches IBW = 45.5 kg + 9.2 IBW = 54.7 kg The woman's actual weight is greater than the IBW + 30%, so calculate the ABW: ABW = 54.7 kg + 0.4( 80kg - 54.7 kg) ABW = 54.7 kg + 0.4( 25.3 kg ) ABW = 54.7 kg + 10.1kg ABW = 64.8 kg
abg interpreter
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pH CO2
HCO3
Normal Arterial Blood Gas Values
pH PaCO2 PaO2 HCO3 O2 Saturation BE 7.35-7.45 35-45 mm Hg 80-95 mm Hg 22-26 mEq/L 95-99% +/- 1
Four-Step Guide to ABG Analysis 1. Is the pH normal, acidotic or alkalotic? 2. Are the pCO2 or HCO3 abnormal? Which one appears to influence the pH? 3. If both the pCO2 and HCO3 are abnormal, the one which deviates most from the norm is most likely causing an abnormal pH. 4. Check the pO2. Is the patient hypoxic? I used Swearingen's handbook (1990) to base the results of this calculator. The book makes the distinction between acute and chronic disorders based on symptoms from identical ABGs. This calculator only differentiates between acute (pH abnormal) and compensated (pH normal). Compensation can be seen when both the PCO2 and HCO3 rise or fall together to maintain a normal pH. Part compensation occurs when the PCO2 and HCO3 rise or fall together but the pH remains abnormal. This indicates a compensatory mechanism attempted to restore a normal pH. I have not put exact limits into the calculator. For example, it will perceive respiratory acidosis as any pH < 7.35 and any CO2 > 45 (i.e. a pH of 1 and CO2 of 1000). These results do not naturally occur.
pH Respiratory Acidosis Acute Partly Compensated Compensated Respiratory PaCO2 HCO3
< 7.35 < 7.35 Normal
> 45 > 45 > 45
Normal > 26 > 26
Alkalosis Acute Partly Compensated Compensated Metabolic Acidosis Acute Partly Compensated Compensated Metabolic Alkalosis Acute Partly Compensated Compensated
> 7.45 > 7.45 Normal
< 35 < 35 < 35
Normal < 22 < 22
< 7.35 < 7.35 Normal
Normal < 35 < 35
< 22 < 22 < 22
> 7.45 > 7.45 Normal
Normal > 45 > 45
> 26 > 26 > 26
Mixed Disorders It's possible to have more than one disorder influencing blood gas values. For example ABG's with an alkalemic pH may exhibit respiratory acidosis and metabolic alkalosis. These disorders are termed complex acid-base or mixed disorders. *This table is able to classify most clinical blood gas values but not all. In cases where blood gas values do not fall into any of the above classifications, an answer "unable to determine" will appear when using the interpreter. For example a pH of 7.428, pCO2 43.6, and a HCO3 of 29.1 do not match any of the classifications (I found these results in someone's chart). While the pH and pCO2 are normal, the HCO3 is abnormally high.
convert fahrenheit & celsius
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enter temperature convert to Fahrenheit convert to Celsius result solution
Directions
Enter temperature to be converted in degrees Fahrenheit (°F) or Celsius (°C aka centigrade) in box. Select either Fahrenheit or Celsius button to perform conversion. Press "convert" button to display result at bottom.
Formula
°C x 9/5 + 32 = °F (°F - 32) x 5/9 = °C
Examples
1) Convert 37°C to Fahrenheit. 37°C x 9/5 + 32 = 98.6°F OR
37°C x 9 + 32 = 98.6°F 5
2) Convert 98.6°F to Celsius. (98.6°F - 32) x 5/9 = 37°C OR
(98.6°F - 32) x 5 = 37°C 9
Formulae
cm x 0.39* = in in 1 = ft 2 in x 2.54 = cm
Examples
If a woman is 5 foot, 3 inches (5' 3"), what is her height in centimeters?
(5' x 12) + 3" = 63" 63" x 2.54 = 160 cm
If a woman is 5 foot, 8 inches (5' 8"), what is her height in centimeters? (5' x 12) + 8" = 68" 68" x 2.54 = 172.7 cm If a man is 203.2 centimeters tall, what is his height in feet and inches? 203.2 cm x 0.3937008 = 80"
80 = 6.67' 12
.67 x 12 = 8.04 remainder
80 = 6 ft and remainder = 8 in 12
OR
6' 8"
Dosage By Weight Questions Given the weight of a patient and a dosage specified in terms of weight, calculate the necessary dosage. These problems are a type of pediatric dosage calculations.
Formula: Weight in Kg * Dosage Per Kg = Y (Required Dosage)
Example: A doctor orders 200 mg of Rocephin to be taken by a 15.4 lbinfant every 8 hours. The medication label shows that 75-150 mg/kg per day is the appropriate dosage range. Is this doctor's order within the desired range? Weight in Kg * Dosage Per Kg Convert 15.4 lb to kg.
•
= Y (Required Dosage)
lb → kg
( ÷ by 2.2 )
• 15.4 lb ÷ 2.2 = 7 kg 7 kg * 75 = 525 mg (Minimum Desired mg/kg Dosage)
7 kg * 150 mg/kg
= 1,050 mg (Maximum Desired Dosage)
24 hours in one day and the medication is ordered every 8 hours.
• • •
24 hrs / 8 hrs = 3 times per day doctor ordered medication 200 * 3 = 600 mg ordered per day 600 mg is within the desired range of 525-1,050 mg
Yes doctor has ordered a dosage within the desired range.
Example: Solumedrol 1.5 mg/kg is ordered for a child weighing 74.8 lb. Solumedrol is available as 125 mg / 2mL. How many mL must the nurse administer? Weight in Kg * Dosage Per Kg Convert 74.8 lb to kg.
• •
= Y (Required Dosage)
lb → kg
( ÷ by 2.2 )
74.8 lb ÷ 2.2 = 34 kg 34 kg * 1.5 = 51 mg/kg mg
•
This is now an ordinary Mass/Liquid For Liquid Question. 51 mg is ordered
and the medication is available as 125 mg / 2 mL. Ordere x Volume Per = Y (Liquid d Have Required) Have
51 mg 125 mg
x2 mL
= 0.82 mL
Fluid Maintenance Requirement Questions Given the weight of a child or infant, calculate the necessary amount of fluid per day. Different hospitals may have different policies, but for learning how to perform these pediatric dosage calculations, the following commonly used table of fluid requirements may be used. Weight Range 0-10 kg 10-20 kg 20-70 kg Over 70 kg Required Daily Fluid 100 mL per kg 1,000 mL + 50 mL per each kg above 10 kg 1,500 mL + 20 mL per each kg above 20 kg 2,500 mL (adult requirement)
Example: An infant weighs 4 kg. What is the required amount of fluid per day in mL? 0-10 kg
•
100 mL per kg
4 kg x 100 mL/kg = 400 mL
Example: An infant weighs 30.8 lb. What is the required IV flow rate in mL/hr to maintain proper fluid levels? Convert 30.8 lb to kg.
• •
lb → kg
( ÷ by 2.2 )
30.8 lb ÷ 2.2 = 14 kg 10-20 kg 1,000 mL + 50 mL per each kg above 10kg
•
14 kg - 10 kg = 4 kg (There are 4 kg over 10 kg).
• •
1,000 mL + (50 mL/kg x 4 kg) = 1,200 mL/day This is now an ordinary IV Flow Rate - mL Rate Question. The required
volume is 1,200 mL and the time is one day. Volume = Y (Flow Rate in (mL) mL/hr) Time (hr) There are 24 hours in one day. 1 day x 24 = 24 hr 1,200 = 50 mL mL/hr 24 hr
•
