Question

weight-based heparin protocol

1. bolus with heparin at 80 units/kg
2. begin intravenous infusion of heparin at 18 units/kg/hr using 25,000 units heparin in 250 ml d₅w or a concentration of 100 units per ml.
3. aptt 6 hours after rate change and then daily at 7am
4. adjust intravenous heparin daily based on aptt results

• aptt less than 35 sec, bolus with 80 units/kg and increase rate by 4 units/kg/hr.
• aptt 35-45 sec, bolus with 40 units/kg and increase rate by 2 units/kg/hr.
• aptt 46-70 sec, no change.
• aptt 71-90 sec, decrease rate by 2 units/kg/hr.
• aptt greater than 90 sec, stop heparin infusion for 1 hour, and decrease rate by 3 units/kg/hr.

using the weight-based heparin protocol, calculate the following:
what will be the initial iv infusion rate if the patient weighs 140 lbs?
(round to the nearest whole number & insert the numerical value only.)

Explanation:

Step1: Convert pounds to kilograms

Since \(1\) kg \(=\) \(2.2\) lbs, then \(140\) lbs \(=\frac{140}{2.2}\approx63.64\) kg.

Step2: Calculate the initial infusion rate

The initial infusion rate is \(18\) units/kg/hr. So for a \(63.64\) kg patient, the number of units per hour is \(18\times63.64 = 1145.52\) units/hr.

Step3: Calculate the mL/hr

The concentration is \(100\) units/mL. Let \(x\) be the mL/hr. Using the formula \(\text{Rate (mL/hr)}=\frac{\text{Units/hr}}{\text{Concentration (units/mL)}}\), we have \(x=\frac{1145.52}{100}=11.4552\approx11\) mL/hr.

Answer:

\(11\)