Download Chapter 6

Chapter 6
Dosage Calculation of Intravenous
Solutions and Drugs
Copyright © 2011 by Saunders, an imprint of Elsevier Inc. All rights reserved.
Chapter 6
Lesson 6.1
Copyright © 2011 by Saunders, an imprint of Elsevier Inc. All rights reserved.
2
Objectives
• Identify three common problems of
intravenous (IV) therapy.
• Explain how the size of an IV fluid drop
determines the flow rate for IV fluid
infusion.
• List the parts of an order for IV fluids that
are necessary to determine the correct
infusion rate.
Copyright © 2011 by Saunders, an imprint of Elsevier Inc. All rights reserved.
3
IV Therapy Overview
• Directly into bloodstream
• Advantages – immediate action
• Disadvantages – potential for severe
adverse reactions, fluid overload
• Prescriber orders rate
Copyright © 2011 by Saunders, an imprint of Elsevier Inc. All rights reserved.
4
IV Mechanics
• IV flow rate
• Drip rate
• Drop factor
– Macrodrip, microdrip
• Drip chamber
• Administration set
Copyright © 2011 by Saunders, an imprint of Elsevier Inc. All rights reserved.
5
Macrodrip versus Microdrip
Figure 6-1. Drop size differences between a macrodrip chamber
and a microdrip chamber on IV tubing.
Copyright © 2011 by Saunders, an imprint of Elsevier Inc. All rights reserved.
6
Regulating IV Fluids
• 4 important concepts:
– What (type of fluid to infuse)
– Volume (of fluid to infuse)
– Duration (of infusion)
– Rate (of infusion)
• Regulators:
– Controller
– Infusion pump
– Roller clamp
Copyright © 2011 by Saunders, an imprint of Elsevier Inc. All rights reserved.
7
Chapter 6
Lesson 6.2
Copyright © 2011 by Saunders, an imprint of Elsevier Inc. All rights reserved.
8
Objectives
• Correctly calculate IV drug infusion
problems when provided with the volume,
hours to be infused, and drip factor.
• Identify the signs and symptoms of fluid
overload.
• Use the “15-second” rule to determine an
IV flow rate.
• List the required parts of a valid IV therapy
order.
Copyright © 2011 by Saunders, an imprint of Elsevier Inc. All rights reserved.
9
Calculating IV Fluids
• Calculate rate:
– Total volume of infusion
– Duration of infusion (in hours)
– Drop factor (on IV package)
• Used for control roller or slides
• Stated in drops per minute
Copyright © 2011 by Saunders, an imprint of Elsevier Inc. All rights reserved.
10
IV Calculation Formulas
• Macrodrip:
Volume (mL)
Time (min)
× drop factor = drops per min
• Microdrip:
– Much easier!
– mL per hour = drops per min
– Use macrodrip formula, but 60s cancel each other
out
Copyright © 2011 by Saunders, an imprint of Elsevier Inc. All rights reserved.
11
15-Second Rule
• Drops per min ÷ 4
• Regulate roller or slide to release same
number of drops in 15 seconds
• Number of drops in 15 seconds × 4 should
be very close to prescribed rate of drops
per min
Copyright © 2011 by Saunders, an imprint of Elsevier Inc. All rights reserved.
12
Maintaining IV Therapy
• Always practice within state nurse practice
act AND agency policy
• Prescriber’s order always required for
IV therapy and must contain:
– Specific drug or IV solution to be infused
– Dosage or volume
– Duration
– Rate of infusion
Copyright © 2011 by Saunders, an imprint of Elsevier Inc. All rights reserved.
13
Chapter 6
Lesson 6.3
Copyright © 2011 by Saunders, an imprint of Elsevier Inc. All rights reserved.
14
Objectives
• Identify at least three drug categories that
can cause chemical trauma to veins during
IV therapy.
• List three actions to prevent tissue
damage with IV therapy.
• Describe ways to check for a blood return
at the IV site.
• Explain how IV therapy should be modified
for children and older adults.
Copyright © 2011 by Saunders, an imprint of Elsevier Inc. All rights reserved.
15
Infusion Control Devices
• Controllers
– Gravity-run system
– Alarm sounds if malfunction
• Pumps
– Rate greater than gravity
– Better for precision
– Danger of infiltration or extravasation
• Syringe pumps
– Slow IV pushes
Copyright © 2011 by Saunders, an imprint of Elsevier Inc. All rights reserved.
16
IV Therapy Responsibilities
• Check often:
– Flow rate
– Equipment function
– Site condition
• Assess for/prevent complications:
– Infection
– Tissue damage
– Fluid and electrolyte imbalances
Copyright © 2011 by Saunders, an imprint of Elsevier Inc. All rights reserved.
17
IV Site Infection
• Signs and symptoms:
– Redness
– Heat
– Pain around site
– Wound drainage
– Fever (if infection becomes systemic)
• If infection suspected:
– Remove needle, document, notify prescriber
– Apply ice or heat
– Apply sterile dressing with antibiotic ointment
Copyright © 2011 by Saunders, an imprint of Elsevier Inc. All rights reserved.
18
Tissue Damage
• Skin (bruising and clot formation)
• Veins (chemical trauma)
– Causes – hypertonic solutions, potassium
chloride, antibiotics, calcium, magnesium,
alcohol, vasoconstrictive drugs,
chemotherapy drugs
– Phlebitis
– Thrombophlebitis
• Subcutaneous tissue
– Infiltration
– Extravasation
Copyright © 2011 by Saunders, an imprint of Elsevier Inc. All rights reserved.
19
Infiltration
From Hockenberry, M.J., & Wilson, D. (2006). Wong’s Nursing
Care of Infants and Children (8th ed.). St. Louis: Mosby.
Figure 6-5. Appearances of tissues after IV
infiltration (A).
Copyright © 2011 by Saunders, an imprint of Elsevier Inc. All rights reserved.
20
Extravasation with Tissue Necrosis
From Weinzweig, J. & Weinzweig, N. (2005). The
Mutilated Hand, St. Louis: Mosby.
Figure 6-5. Appearances of tissues
after extravasation (B).
Copyright © 2011 by Saunders, an imprint of Elsevier Inc. All rights reserved.
21
Fluid and Electrolyte Imbalance
• Fluid overload signs and symptoms:
– Rapid pulse, elevated blood pressure
– Bulging hand veins, neck veins when upright
– Shortness of breath
– Coughing
– Pitting edema
• Electrolyte imbalances
– Too much IV fluid can dilute blood electrolytes
– Rapid infusion of electrolytes can increase
blood levels to life-threatening levels
Copyright © 2011 by Saunders, an imprint of Elsevier Inc. All rights reserved.
22
Life Span Considerations
• Pediatric:
– Difficulty accessing IV sites
– More likely to dislodge needle
– Narrow range of normal fluid volume
– ALWAYS use microdrip tubing and
volume-controlled IV administration set
• Older patients:
– Difficulty starting and maintaining IVs
– At risk for fluid volume overload
Copyright © 2011 by Saunders, an imprint of Elsevier Inc. All rights reserved.
23