Chapter 18 IV Medication and Titration Calculations Copyright

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Chapter 18 IV Medication and Titration Calculations Copyright © 2010 Delmar, Cengage Learning. ALL

Chapter 18 IV Medication and Titration Calculations Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED.

Titration • Adjustment of dosage within specific range to obtain desirable measurable physiologic response

Titration • Adjustment of dosage within specific range to obtain desirable measurable physiologic response Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED.

Titrated Medications • Many IV medications used in critical care and life-threatening situations to

Titrated Medications • Many IV medications used in critical care and life-threatening situations to alter or maintain vital physiologic functions • Medications requiring titration have very rapid action, short duration, and narrow margin of safety – Require continuous monitoring Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED.

Titrated Medications • Dosages calculated to nearest tenth • Flow rates rounded to nearest

Titrated Medications • Dosages calculated to nearest tenth • Flow rates rounded to nearest m. L – Although some electronic infusion devices (EIDs) can administer medication flow rate to tenth of a m. L Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED.

Titrated Medications • May be prescribed by either: – Dosage • mcg/mg/units per min/hr

Titrated Medications • May be prescribed by either: – Dosage • mcg/mg/units per min/hr – Body weight • mcg/mg/units per kg per min/hr Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED.

Titrated Medications • May be prescribed to infuse within specific range, such as 1

Titrated Medications • May be prescribed to infuse within specific range, such as 1 to 3 mcg/min, to achieve specific physiologic response – e. g. , maintaining systolic blood pressure (BP) greater than 100 millimeters of mercury (mm Hg) Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED.

Titrated Medications • Usually infused using EID – e. g. , volumetric or syringe

Titrated Medications • Usually infused using EID – e. g. , volumetric or syringe pump – Display dosage and flow rates – Can be set to deliver fractional dosages Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED.

Titrating Using gtt/min • Method not recommended • If EID or syringe pump not

Titrating Using gtt/min • Method not recommended • If EID or syringe pump not available, use microdrip tubing (60 gtt/m. L) • Remember: – Rate in gtt/min when using microdrip tubing same as m. L/hr Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED.

Titrating IV Infusion • EIDs used for administration • Flow rates calculated in m.

Titrating IV Infusion • EIDs used for administration • Flow rates calculated in m. L/hr for lowest and highest dosage prescribed and adjusted within this range to elicit desired physiologic response Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED.

Example 1 • Cardiac medication with strength of 125 mg/100 m. L to infuse

Example 1 • Cardiac medication with strength of 125 mg/100 m. L to infuse at rate of 20 mg/hr • Calculate m. L/hr flow rate Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED.

Example 1 = 16 m. L/hr Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS

Example 1 = 16 m. L/hr Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED.

Example 2 • Dosage of 2 mcg/min prescribed using 8 mg in 250 m.

Example 2 • Dosage of 2 mcg/min prescribed using 8 mg in 250 m. L solution • Calculate m. L/hr flow rate Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED.

Example 2 = 3. 75, or 4 m. L/hr Copyright © 2010 Delmar, Cengage

Example 2 = 3. 75, or 4 m. L/hr Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED.

Example 3 • Medication prescribed at rate of 3 mcg/kg/min for adult weighing 95.

Example 3 • Medication prescribed at rate of 3 mcg/kg/min for adult weighing 95. 9 kg • Solution strength 400 mg in 250 m. L • Calculate m. L/hr flow rate Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED.

Example 3 • Calculate 3 mcg/min dosage for 95. 9 kg Copyright © 2010

Example 3 • Calculate 3 mcg/min dosage for 95. 9 kg Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED.

Example 3 Using Two-Step Method • Calculate m. L/hr flow rate for 287. 7

Example 3 Using Two-Step Method • Calculate m. L/hr flow rate for 287. 7 mcg/min = 10. 79, or 11 m. L/hr Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED.

Example 3 Using One-Step Method • First two ratios are same as two-step method

Example 3 Using One-Step Method • First two ratios are same as two-step method m. L 250 m. L 1 mg hr 400 mg 1000 mcg Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED.

Example 3 Using One-Step Method • Match mcg denominator, which is provided by 3

Example 3 Using One-Step Method • Match mcg denominator, which is provided by 3 mcg/kg/min dosage • Enter 3 mcg as numerator m. L 250 m. L 1 mg 3 mcg hr 400 mg 1000 mcg kg/min Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED.

Example 3 Using One-Step Method • Both kg and min must be matched in

Example 3 Using One-Step Method • Both kg and min must be matched in next numerators – Either can be entered first, but min is best choice because conversion ratio is needed to change min to hr – Enter 60 -min-equals-1 -hr conversion m. L hr 250 m. L 1 mg 3 mcg 60 min 400 mg 1000 mcg kg/min 1 hr Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED.

Example 3 Using One-Step Method • Enter 95. 9 kg body weight as final

Example 3 Using One-Step Method • Enter 95. 9 kg body weight as final numerator m. L 250 m. L 1 mg 3 mcg 60 min 95. 9 kg hr 400 mg 1000 mcg kg/min 1 hr Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED.

Example 3 Using One-Step Method • After cancelling alternate denominator/ numerator measures, only m.

Example 3 Using One-Step Method • After cancelling alternate denominator/ numerator measures, only m. L and hr remain • Complete the math m. L 250 m. L 1 mg 3 mcg 60 min 95. 9 kg hr 400 mg 1000 mcg kg/min 1 hr = 10. 79 = 11 m. L/hr Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED.

Example 4 • • Titrating IV infusion Dosage of 2 to 4 mcg/min prescribed

Example 4 • • Titrating IV infusion Dosage of 2 to 4 mcg/min prescribed Solution being titrated has 8 mg in 250 m. L Calculate flow rate of medication for 2 to 4 mcg range Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED.

Example 4 Using Two-Step Method = 3. 75, or 4 m. L/hr Copyright ©

Example 4 Using Two-Step Method = 3. 75, or 4 m. L/hr Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED.

Example 4 Using One-Step Method = 3. 75 or 4 m. L/hr Copyright ©

Example 4 Using One-Step Method = 3. 75 or 4 m. L/hr Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED.

Example 4 • Since upper dosage range flow rate is twice that of lower

Example 4 • Since upper dosage range flow rate is twice that of lower dosage range flow rate (4 m. L/hr), multiply by two • Flow rate range is 4 to 8 m. L/hr Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED.