Principle Concepts of Iv therapy

Multidisciplinary functions RN: Monitor, Set, Regulate PCP: Determine IV Fluid Pharmacy: Preparation Education: Use of Equipment

Primary vs secondary lines Primary line Larger Continuous unless secondary is active Secondary line Smaller volume “Piggy-back” Must not be introduced in high-alert fluid lines!

Placement of secondary lines Injection ports If pump is used, above the pump If no pump, close to IV insertion site Secondary infusion bags are always placed higher than the primary solution bags

Drip chamber Used to monitor flow by observing drops Squeeze chamber to fill half-full with fluid Allows drops to be observed easily Prevents air from entering system

Iv clamps Roller clamps allow adjustment of flow Auxiliary clamps can stop flow temporarily without changing the rate set by the roller clamp

ports May be for needle- or needleless system Allow for injection of medication into the line Allow for attachment of secondary line Never puncture a needleless system port with a needle!

Needleless systems Designed to limit needlestick injuries Ease of disposal Reduces potential bacteremia

Iv fluids and gravity IV fluids flow by gravity Must be above patient’s heart level 3’ above the heart is the desired height As the patient’s position changes, the IV bag height must be adjusted

Monitoring flow rate At a minimum, every hour After every position change More frequently for pressors, antiarrhythmics, and other critical drugs and fluids

Secondary lines Infusion of medications Intermittent IVPBs hang higher than primary bag Gives IVPB bag greater pressure Causes IVPB to infuse first IVPB set includes an extender to be used on the primary bag When IVPB complete, primary bag will begin its flow automatically

Preparation of IVPB Prepackaged Mixed by Pharmacy Mixed by RN on unit

Safety check compatibility

Use of volume controlled burette Used for greater accuracy in measuring smaller volumes 100-150 ml Measured in microdrops Chamber filled from primary IV to desired amount Medication injected into port Desired rate set manually or through pump

Use of volumetric pumps Can deliver volumes too small to measure by drips (e.g., 0.1 ml per hour) May be large volume (replacement fluids) or small volume (insulin, hormones) May come with several safety features (flow alarms, air alarms, drug libraries) Or, may flow even when infiltration occurs Never turn off an IV alarm!

Identifying common components of iv fluids DEXTROSE: “D” May be in various percentages: D5, D10 WATER: “W” Refers to sterile water SALINE: “S” May be Normal Saline (NS or 0.9%), ½ NS or ¼ NS ELECTROLYTE SOLUTION: “LR” or “RL” or “RLS” Ringer’s lactate Lactated Ringer’s

Iv drop sizes Drops per mL (gtt/mL) required to calculate any flow rate Will be identified on IV tubing packaging “Microdrip” is always 60 gtt/mL

Methods of calculating flow rates Ratio and proportion method Dimensional analysis method Formula and division method Division factor method Any of these methods is helpful if you understand the principles behind it!

Ratio and proportion method First find the mL per min by dividing the mL per hour by 60 (60 minutes in 1 hour): 125 mL ÷ 60 = 2 mL/ min If we know we are to give 2 mL per minute, set up a proportion using the known drops per mL based on the type of tubing used (e.g., 10 gtt/mL): 10 gtt = x gtt = 20 gtt/min 1 ml 2 mL

Dimensional analysis method Must have rate in mL per hour Your unknown is in gtt/min Therefore, start with your drop factor to have gtts = gtts in your answer: gtt = 10 gtt min 1 mL Add the “desired” mL per hour rate: gtt = 10 gtt x 125 mL min 1 mL 1 hr Add neutral time value: 1 hr 60 min Cancel repeating numerator/denominator values: gtt = 10 gtt x 125 mL x 1 hr = 21 gtt/min 1 mL 1 hr 60 min

Formula and division method Useful only in small volumes Must be completed in less than 60 minutes Flow rate = mL/hr Volume x set calibration Time (60 min or less) 125 mL x 10 gtt/mL = 21 gtt/min 60 min

Division factor method Must have rate as mL/hr Can similarly divide the mL per hour by the constant drip factor Drip factor is obtained by dividing set calibration into 60: 60 ÷ 10 gtt/mL = 6 60 ÷ 15 gtt/mL = 4 60 ÷ 20 gtt/mL = 3 60 ÷ 60 gtt/mL = 1

Example factor method 1 125 mL x 10 gtt/mL = 21 gtt/min 60 min 6 …is the same as: 125 ÷ 6 = 21 gtt/min