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Amy Gutman MDEMS Medical Director
PARAMEDIC PHARMACOLOGY:
INTRAVENOUS FLUIDS & DRUG CALCULATIONS
Review of fluids & electrolytes
Techniques of intravenous & intraosseous infusions
Mathematical principles used in pharmacology & to calculate medication doses
Medication administration routes
OVERVIEW
#1 I am a woman I am bad at math Do not extrapolate ALL
women are bad at math
#2 This is a boring lecture This is a necessary
lecture Do not extrapolate ALL
my lectures are boring
DISCLAIMERS
Discussed Today
Intravenous (IV)Intraosseous (IO)
Other Routes
Sublingual (SL)Subcutaneous (SQ)Parenteral (PO)Rectal (PR)Inhalation (IH)Endotracheal (ET)Transdermal (TD)Intramuscular (IM)Intranasal (IN)
MEDICATION ADMINISTRATION ROUTES
Provider integrates pharmacology knowledge to formulate a treatment plan intended to mitigate emergencies & improve the overall health of patient
Administer medications within scope of practice
Understand “six rights” of medication administration
Understand advantages, disadvantages & techniques for establishing venous access
Review math concepts, including dose & rate calculations
Describe role of medical direction
NATIONAL EMS EDUCATION STANDARD COMPETENCIES ~ PHARMACOLOGY
Medication administration governed by local protocols &/or online medical direction
Standing Orders: Off-line or indirect medical control of predefined procedures
Online (Direct) Medical Control: Must contact physician prior to performing certain procedures
When in doubt, contact medical control
When an order is given: If unclear or inappropriate, ask physician to repeat the order Repeat back for confirmation the name, dose & route of
delivery
MEDICAL DIRECTION
In ill or injured patients, survival may depend on ability to obtain access for fluid & drug resuscitation Peripheral extremity Eternal jugular vein Intraosseous
Harm can result from improper technique or insuffi cient pharmacology knowledge
VASCULAR ACCESS
Right patient
Right drug
Right dose
Right route
Right time
Right documentation
“RIGHTS” OF MED ADMINISTRATION
Knowledge necessary prior to administration Mechanism of action Indications Contraindications Side effects Routes of administration Pediatric & adult doses Dose calculations Antidotes / reversal
agents
MEDICATION ADMINISTRATION
Name of drug
Dose of drug
Time administered
Administration route
Name of person administering drug
Patient’s response to drug
DOCUMENTATION
At beginning of each shift, check drugs, supplies & equipment Not expired Not damaged Readily available in required quantities
Paramedic responsible for documentation & security of all controlled substances State, regional & local distribution, security, exchanges &
accountability policies Double lock system in each vehicle & at base storage Drug log must be kept for at least 3 years Medical director DEA number used to order narcotics
DRUG CHECKS & LOGS
Treat all bodily fluids as infectious I don’t shake pt’s hands
without gloves (especially kids)
PPE, gloves & protective eyewear at all times Include full facial protection if
possible splatter
CDC states hand-washing most effective method to prevent the disease spread
UNIVERSAL PRECAUTIONS
Routine & thorough hand-washing
Hand-sanitizer before & after every patient contact if no easy access to soap & water
Keep equipment in clean conditions with disinfection between each patient & every shift
Antiseptics prior to any invasive procedure
Check linen, equipment & supplies prior to use for intactness, cleanliness
ASEPSIS
After needle penetrates skin, it is contaminated
After needle unsheathed, it is a weapon
Immediately dispose of sharps in a puncture-proof sharps container
Follow your agency protocol for disposal of infectious waste & cleaning of contaminated equipment
CONTAMINATED MATERIALS CLEANING OR DISPOSAL
Specific protocol
Specifics to that medication or IVF: Indications / Contraindications Therapeutic effects Side effects Appropriate dose & re-dosage Need (+/-) for medical control
Allergies: Known by patient Obtain from reliable source if not from patient Check for medic-alert jewelry or tags.
BASIC PHARMACOLOGY KNOWLEDGE
INTRAVENOUS FLUIDS
Based upon presenting & underlying illness or injury
Even a small amount of the poorly chosen fluid may be harmful to a patient
Most agencies have limited choices of each IVF class – easy to familiarize yourself with specifics of each
CHOOSING APPROPRIATE IVF
BODY COMPARTMENTS
Commonly used prehospitally Normal saline, lactated ringers,
dextrose & saline or water
Made of water & electrolyte solutions that easily cross a semi-permeable membrane
Rapidly alter intravascular fl uid levels
Non-oxygen carrying
Given as a constant rate or bolus Adult: 250cc Pediatric: 20cc/kg In trauma, consider permissive
hypotension
CRYSTALLOIDS
0.45% Normal Saline
Dilutes serum by pulling water from vascular compartment into interstitial compartment
Used for hyperosmolar conditions l ike severe dehydration Leads to hyponatremia if plasma sodium normal as has lower
concentration of sodium than serum Cells swell & burst from increased osmotic pressure If rapidly infused causes cerebral edema & central pontine
demyelinosis
May cause sudden fl uid shift from intravascular space to intracellular space leading to cardiovascular collapse
Slower but deadly is third spacing ~ abnormal shift into serum if not enough protein to “hold” fl uid in vascular space
IV FLUIDS: HYPOTONIC
1.8% - 10% saline, mannitol
Osmolarity higher than serum as has more particles than serum
Pulls fluid & electrolytes from the intracellular to intravascular (ECF) compartment
Large volumes cause hypernatremia & severe dehydration Cells may collapse from increased extracellular osmotic
pressure
A little goes a long way to: Increase BP Reduce cerebral edema
IV FLUIDS: HYPERTONIC
0.9% Normal Saline
Principal resuscitation fluid
Contains sodium, potassium, chloride in almost same concentrations as “body water” or “plasma”
Iso-osmolar compared to plasma so stays almost entirely in the extracellular space
3-1 replacement rule: 3cc isotonic solution needed to replace 1 mL of blood
IV FLUIDS: ISOTONIC
Albumin, blood, dextran, hetastarch
Contain particles which do not readily cross semi-permeable membranes
Volume stays almost entirely within intravascular space for prolonged time compared to crystalloids
Because of gelatinous properties cause platelet dysfunction interfering with fibrinolysis & coagulation factors (factor VIII)
Can cause significant coagulopathy in large volumes
IV THERAPY: COLLOIDS
Blood contains hemoglobin which carries oxygen to cells
Impractical for prehospital unless specialized critical care transport Refrigeration & unique storage “Non-cross matched blood”, or “type O”
expensive, rare, with potential complications
Synthetic blood available, but rarely used outside trauma research institutions or the military PolyHeme, HemoPure (HBOC
Hemoglobin-Based O2 Carrying Solutions)
OXYGEN-CARRYING SOLUTIONS
CHOOSING THE RIGHT SITE:
ANATOMY & TECHNIQUES
Based on purpose of IV, patient age, location
Over-the-needle catheters preferred in prehospital setting Readily secured Minimally cumbersome Allow for some patient movement Do not need to immobilize the
entire limb
Sized by diameter (gauge) Smaller gauge = larger diameter Choose largest-diameter catheter
for chosen vein New needles retract after insertion
CHOOSING AN IV CATHETER
Gloves, PPE
Tape & bio-occlusive dressing
Tourniquet
Alcohol, betadine, chlorhexadine
Arm board
Sharps container
EQUIPMENT NEEDED
IV solution Medical: NS Trauma: LR or NS* Medication drip: NS or D5W
Administration set w/ extension tubing Macro drip (10-15 gtts/cc) for volume Micro drip (60 gtts/cc) for medications
Catheter >12 yo + fluid resuscitation: 16-18g, IO <12 yo +/- fluid resuscitation: 20-24g, IO <6 yo: 20-24g, IO
EQUIPMENT NEEDED
Most packaged in clear plastic bags
Labeling: Fluid type Expiration date
Do not use after expiration date, appear cloudy, discolored, with visible particulate, or if packaging not intact
IV SOLUTION CONTAINERS
Over-The-Needle Hollow-Needle
INTRAVENOUS CANNULAS
Macrodrip 10 gtts = 1 mL, for large
amounts of fluid
Microdrip 60 gtts = 1 mL, for
restricted amounts of fluid
Measured volume & secondary infusion sets
Blood tubing Filter prevent clots from
entering body
IV ADMINISTRATION SETS
Blood type identified by obtaining blood type & cross-match
“Blood-band” identifies blood type & blood product hung Blood must be checked against bracelet & verified by
medic even if already checked by nursing
Blood administered through specific tubing
Assess vitals q15 mins & monitor for hemolytic reactions
Tachycardia, hives, respiratory distress, CP
BLOOD TRANSFUSIONS
PERIPHERAL ACCESS
Prepare new bag / bottle
Occlude flow from depleted bag or bottle
Remove spike from depleted & insert into new IV bag / bottle
Open clamp to & titrate to appropriate flow rate
CHANGING INTRAVENOUS BAG OR BOTTLE
Thick fluids (colloids) infuse slowly
Cold fluids run slower than warm fluids
Height of IV bag must overcome gravity if not a pressure bag
The larger the diameter, the faster fluid can be delivered
Check for constricting band, BP cuff
Evaluate for infi ltration or trauma proximal to IV site
FACTORS AFFECTING IV FLOW RATES
Puncturing vein may cause massive hematomas
Tape may damage skin
Use smaller catheters (20, 22, 24 g)
Cardiovascularly sensitive to rapid fluid shifts
Poor vein elasticity
GERIATRIC CONSIDERATIONS
Pain
Infection / Phlebitis
Allergic reaction
Catheter shear
Arterial puncture
Circulatory overload
Air embolism
Necrosis
IV ACCESS COMPLICATIONS
Escape of fl uid into surrounding tissue IV catheter passes through vein IV becomes dislodged Catheter inserted at too shallow an angle only entering
fascia
SSX: Edema at the catheter site Continued IV flow after proximal vein occlusion Tightness, burning, pain at IV site
Treatment: Discontinue IV & reestablish in opposite extremity or more
proximal location Apply direct pressure
IV COMPLICATION ~ INFILTRATION
Vein, catheter or tubing blockage
1 s t sign is decreasing / no drip rate or blood in tubing
Causes: Position of catheter within the vein BP overcoming flow Tourniquets!
Inject 1-5 cc saline into IV to gently increase pressure to overcome obstruction & reestablish fl ow If occlusion does not dislodge, discontinue IV
& re-establish in opposite extremity or proximal to current site
IV COMPLICATION ~ OCCLUSION
Hematoma Accumulation of blood in tissues
around IV Causes: vein perforation, improper
catheter insertion or removal Stop IV, apply direct pressure
Arterial puncture Bright red spurting blood Suspect if you have a great IV that
does not flow, after checking for obstruction
Withdraw catheter, apply direct pressure for 5 mins or bleeding stops
Always check for a pulse prior to cannulation
IV COMPLICATIONS ~ HEMATOMA & ARTERIAL PUNCTURE
Anaphylaxis Sensitivity to IV fluid or
medication Treat according to allergic /
anaphylaxis protocol
Pyrogenic reactions Pyrogens are foreign proteins
capable of producing fever secondary to allergic reactions
Characterized by abrupt fever with chills, backache, HA, N/V, weakness
Stop infusion immediately Treat according to allergic /
anaphylaxis protocol
IV COMPLICATIONS ~ SYSTEMIC
IV COMPLICATIONS ~ NECROSIS & INFECTION
Healthy adults can handle 2-3 extra liters of crystalloids
Problems pts with cardiorespiratory or renal dysfunction who can’t tolerate hemodynamic stress from increased circulatory volume
SSX: Dyspnea, JVD, HTN, rales, hypoxia,
edema
Treat by converting to saline lock, respiratory distress protocol
IV COMPLICATIONS ~ CIRCULATORY OVERLOAD
Flushing IV line & replacing empty IV bags limits likelihood of air embolism
SSX: Respiratory distress, unequal BS,
cyanosis Focal neurological symptoms Shock & cardiorespiratory arrest
Treatment: LLR & Trendelenburg position 100% oxygen, treat specific symptoms
according to pertinent protocol Rapid transport
IV THERAPY COMPLICATIONS ~ AIR EMBOLUS
Part of catheter pinches against needle & slices through catheter creating a free-flowing segment
SSX similar to air embolus
Treatment Surgical removal of the tip LLR & Trendelenburg Do not rethread
IV COMPLICATIONS ~ CATHETER SHEAR
More than using a “BFN”
Have a favorite site, favorite “Jelco” & favorite technique
Have a back-up And a back-up to your
back-up
Practice, practice, practice
CHOOSING THE RIGHT SITE
ANTECUBITAL VEIN
DORSAL “DIGITAL” VEINS
EXTERNAL JUGULAR
ACCESSING EXTERNAL JUGULAR VEIN
Technique of administering fl uids, blood products & drugs into intraosseous space of tibia, humerus or sternum
Long bones consist of a shaft (diaphysis), the ends (epiphyses) & growth plate (epiphyseal plate)
IO space is spongy cancellous epiphyseal & diaphysis medullary cavity.
When in shock, peripheral veins collapse making IV access diffi cult
IO space always patent to rapidly absorb fl uids & drugs, similar to a central l ine
INTRAOSSEOUS
Cannot locate landmarks
Fractures at / above site
Amputations distal to site
Previous surgery at site
Infection at site
Local vascular compromise
Previous attempt in same site
Osteogenesis imperfecta
Occasionally diffi cult in combative & the obese
GENERAL IO CONTRAINDICATIONS
Identify landmarks & anatomy
Have all equipment ready prior to startingManufacturer-specific device & equipment
IV tubingMedications
IO INFUSION
OBJECTIVE Determine time difference to obtain IO vs IV wearing
HazMat PPE
METHODS 22 EMT-Ps placed anterior tibial EZ-IOs & antecubital
IVs Measured: time to skin access, vascular access & fluid
infusion
CONCLUSIONS With provider & mannequin in PPE, needle to skin
time, vascular access time, & fluid infusion time all favored EZ-IO
SYYAMA J, ET AL. IO VS IV ACCESS WHILE WEARING PPE IN A HAZMAT SCENARIO. PEC
2007
HUMERAL IO
Supine position, humerus adducted
Palpate midshaft humerus proximally until reach humeral head
At shoulder there is a protrusion (greater tubercle) which is the insertion site
With opposite hand “pinch” anterior & inferior aspects of humeral head to confi rm position of greater tubercle
Stabilize arm, place IO at 90 degree angle to skin
Humeral cortex less dense than tibia so minimal force required
HUMERAL APPROACH
DISTAL TIBIA IO
Landmarks are anterior distal tibia & medial malleolus (middle ankle bone protrusion)
Medial insertion site, 2 finger widths proximal to medial malleolus
“Big Toe = IO”
DISTAL TIBIAL APPROACH
PROXIMAL TIBIA IO
Tibial tuberosity is round protrusion distal to patella
From tuberosity, move 1 inch medially to tibial plateau
From tibial plateau, go proximally 0.5 inch towards patella
This is thinnest portion of tibial bony cortex
PROXIMAL TIBIA APPROACH
STERNAL IO
STABILIZE THE IO
STABILIZE THE BABY
Large, deep veins that do not collapse until late shock Internal jugular, subclavian,
femoral
Though IO “peripheral”, it’s flow rate & placement in marrow makes it function essentially as central access
CENTRAL VENOUS ACCESS
Surgically implanted device permitting repeated access to central venous circulation
Generally located on anterior chest near the 3 rd-4th rib lateral to sternum
Accessed with a special needle specific to the device
Requires special training
CENTRAL ACCESS DEVICE
Dilated vein acts like an artery due to AV graft
Do not access!
Most common complication is bleeding
Direct pressure +/- proximal tourniquet
DIALYSIS FISTULA
MATHEMATICAL PHARMACOLOGY
PRINCIPALS
Vials Single or multi-dose Draw air into syringe,
inject into vial & withdraw drug
Ampules Tap neck area to drain
fluid Using 4X4, snap neck of
vial & withdraw drug Dispose of ampule
pieces in sharps container
Prefilled Syringes Remove caps & screw
pieces together Dispel air & use as
standard syringe
Dry Powder meds Depress plunger in vial
to mix with prepackaged saline
Mix thoroughly until particulates completely absorbed
IV MEDICATION PACKAGING
Decimal system based on multiples of ten measuring length (meter), volume (liter), weight (gram)
Prefi xes indicate fraction of base being used Micro = 0.00001 Milli = 0.001 Centi = 0.01 Kilo = 1,000
Drugs packaged in diff ering units of weight & volume so conversion often required
METRICS
Necessary information:Desired dose (amount of drug)
Drug concentration (total weight of drug contained in specific amount of volume)
Volume on hand (volume of solution containing drug)
BASICS OF DOSE CALCULATION
Most pediatric drugs weight-based Length-based
resuscitation tape Pediatric wheel charts EMS field guide /
Smartphone app
Once weight known, calculations same as for adults
PEDIATRIC DRUG DOSAGES
1 gram (g) = 1000 milligrams (mg)
1 mg = 1000 micrograms (mcg)
1 liter (L) = 1000 milliliters (ml)
If going from large to small value, move decimal point to right
If going from small to large value, move decimal point to left 1 Kg = 1000 g 1Kg = 1,000,000 mg 1 Kg = 1,000,000,000 mcg
METRIC CONVERSIONS
Kg x 2.2 = pounds (lbs) 1 Kg = 2.2 lbs 3 am: (lbs/2) – 10% =
kg
To convert kg to lbs: Kg x 2.2 = lbs (Kg x 2) + 10% = lbs
POUNDS TO KILOGRAMS
You want to give 5mg valium. Label states 10 mg in 2cc (10mg/2cc). How many cc’s will you give?
Therefore…1 cc of valium = 5mg of valium
Phenergan ordered for 12.5 mg Supplied in 25 mg/ 2cc Therefore 12.5 mg / 1cc
CALCULATION EXAMPLE
5mg x 2cc = X cc
10 mg
Adjust flow rate according to pt’s condition & per protocol
You must know: Volume to be infused Period over which it is to be infused Properties of the administration
Therefore, flow rate is: Volume to be infused x gtt/mL of administration set/total
time of infusion in minutes = gtt/min
CALCULATING FLUID INFUSION RATES
Desired dose (D) x Patient’s kg Weight (W) = Volume to be Administered (X)
Known dose on hand (H)
WEIGHT-BASED CALCULATIONS
You are giving 0.5 mg/kg IVP to an 80kg patient. Drug prepackaged in 100mg/10cc
To determine total dose: 0.5mg x 80kg = 40mg
To determine total volume: 40 mg x 10cc = 4cc total volume
100 mg
CALCULATION EXAMPLE
Desired dose x Size of bag x gtt set = gtt/min
Order is for 5 mg/min. You have 500cc NS, a 60 gtt/cc admin set & 2g of drug. How many gtt/min?
DRIP RATE CALCULATIONS
Desired Dose x Volume of IV Bag x Administration Set gtt = gtt / min
Amount of Drug
5mg/min x 500cc x 60gtt/ cc = 75gtt / min
2000mg
Volume x administration set / time (cc x gtt) / minutes
You want to give a 500cc bolus using a 15 gtt set over 1 hour (500cc x 15gtt) / 60 mins = 125
gtts/min
SIMPLER DRIP RATECALCULATION
Caroline’s Emergency Care in the Streets 7 t h Edition (Principles of Pharmacology, Medication Administration & Emergency Medications). Jones & Bartlett. 2013
Pharmacology Drug Dosage Calculations. Shelby County EMS Training Division 2010
Linscott et al. Emergency Care. IV Access, Blood Sampling & IO Infusions. Brady 2009.
Photo credits (IV insertion, EJ cannulation) Scott Metcalf MD©
REFERENCES
Find math formula or system that works for you Use Smartphone but remember that
phones die! Back-up with paper, pen & brain
IVF classes, pathophysiology & indications
Diff erent techniques, equipment & indications for vascular access
“6 rights” of drug administration including basics of BLS & ALS medication utilization
When in doubt contact medical control