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Dose Calculations- Drug Dose Calculation Formulas, IV Dosage Calculations, Pediatric Drug Dose Calculations, Infusion Rate, Online Dose Calculators and etc
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IV drip calculation:

IV drip rate is calculated by this simple formula: IV Drip Rate (gtt/min) = Total Volume (mL)/Time (min) x Drop Factor (gtt/mL) This equation can also be rearranged to calculate the time required for an infusion, when provided the volume to be infused, the drip rate, and the drop factor.

Formula: IV Drip Rate (gtt/min) = Total Volume (mL)/Time (min) x Drop Factor (gtt/mL)
IV drip rate online calculator: Find Here

Drip factor:

The drip factor refers to the number of drops per milliliter of solution calibrated for an administration set.

Application: An IV drip rate is a way of describing the rate of an intravenous infusion based on the number of drops (gtt) that are administered to the patient per minute. This is influenced by the type of the tubing (microdrip or macrodrip), the total volume that is required to be infused, and the time over which the infusion is ordered to run. Drip factor can be used to calculate the Infusion rates of IV Fluids

Formula: Drip Rate = Volume (mL)* Time (h)
For example: for macro drip tubing with a drip factor of 20 gtt/mL, 20 drops is equivalent to one mL

Drop factor:

Drop factor = the number of drops it takes to make up one ml of fluid. Two common sizes are: 20 drops per ml (typically for clear fluids) 15 drops per ml (typically for thicker substances, such as blood)

Application-An IV drop factor reflects the specific size of the drops of IV fluid that the tubing set creates. This is a predetermined number based on the tubing required and available to administer the medication. Tubing can be either microdrip or macro-drip. Drop factor can be used to calculate the dose for ophthalmic solutions.

Formula: Drop factor = (Drops per minute * Time) / Volume
For example: IV order D51/2 NS at 120 ml/hr The drop factor is a 15 gtts/ml and the flow rate is 120 ml/hr.

IV drop per minute calculator - Find Here

Drip Rate:

The IV flow rate is defined as the number of drops of medication a patient receives over a determined time (e.g., drops per minute). One drop is quite a small amount and cannot be divided into smaller parts - so the values for IV flow rate in this calculator are rounded to the digit's column.

Formula: Drip rate (mL/hour) = Total volume (mL) / Infusion time
Online Flow Rate Calculator Link-Find Here

Macro drip factor:

Application-Macro drip IV tubing is the more standard tubing type, and has larger drops of fluid than micro drip tubing. The macrodrip drip factor is generally somewhere between 10 and 20 gtt/mL.

Formula: For sets that deliver 10 gtt/ml, divide the flow rate by 6. For sets that deliver 15 gtt/ml, divide the flow rate by 4. For sets that deliver 20 gtt/ml, divide the flow rate by 3.
For example: for macro drip tubing with a drip factor of 20 gtt/mL, 20 drops is equivalent to one mL. If you set the rate at 20 drops per minute, one mL is infusing per minute, or 60 mL per hour.

Macro drip factor calculating: Macro drip tubing delivers 10-20 gtt/mL and is used to infuse large volumes or to infuse fluids quickly.

Micro drip factor:

Application-Micro drip IV tubing creates minimal drip sizes for medications that are potent and must be carefully administered and/or for patient populations that are highly sensitive to large doses of medications (namely, neonatal and pediatric patients). The micro drip factor is generally estimated at 60 gtt/mL.

Formula: IV drip rate= (60/mL) * volume/time.
For example: a solution has a flow rate of 125 ml/hour (125 ml/60 minutes) when using a microdrip set (drip factor of 60 gtt/ml)

Micro drip factor calculating: Micro drip tubing delivers 60 gtt/mL and is used for small or very precise amounts of fluid, as with neonates or pediatric patients.

What is IV drop per min?

Drops per minute (DPM) is used to calculate the IV flow rate of a given volume. When administering intravenous via a gravity line, the rate of flow is determined using drops per minute. This measure is calculated based on the total volume of the administered liquid, total time in hours and drop factor of the giving set. For these calculations, you need knowledge about Unit conversion, Fractions, Long division, Long multiplication, and Decimals.

What is GTT?

Abbreviation meaning drops (from the Latin "guttae", drops). One of a number of hallowed abbreviations of Latin terms that have traditionally been used in prescriptions. It is the number of drops (gtts) in one milliliter (mL) of solution delivered by gravity.

How to calculate GTT?

Formula: IV Drip Rate (gtt/min) = Total Volume (mL)/Time (min) x Drop Factor (gtt/mL)
Examples of Online Drip Calculators for drugs:

1. Lidocaine- Drip Calculator
2. Epinephrine- Drip Calculator
3. Nifedipine- Drip Calculator


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