Week 4 Nursing Flashcards
Body Fluid Compartments
▪ The body has three major fluid compartments:
– Intracellular space
– Interstitial space
– Intravascular space
▪ Separating compartments are two semi-permeable barriers
– Capillary wall
– Cell membrane
Regulation of Body Fluid Compartments
▪ Movement between compartments occurs via these regulatory mechanisms:
– Movement of fluids
▪ Osmosis
▪ Filtration (Hydrostatic & Oncotic pressures)
– Movement of electrolytes
▪ Diffusion
▪ Active Transport
▪ These mechanisms maintain the balance between:-
– Intracellular fluid (ICF) and Extracellular fluid (ECF)
– Interstitial and intravascular spaces
Colloid Osmotic Pressure – Oncotic Pressure
- The capillary membrane is readily permeable to ions. This means that the osmotic pressure in blood vessels is determined principally by the plasma proteins (i.e albumin).
- This osmotic “pull” of these blood proteins is called oncotic pressure.
- Oncotic pressure keeps fluid within the intravascular space.
Hydrostatic pressure
▪ Hydrostatic pressure is the force exerted on the blood vessel wall by a fluid. ▪ As the volume of blood ↑, hydrostatic pressure ↑
▪ The balance between oncotic and hydrostatic pressures determines fluid movement between the intravascular and interstitial spaces
Indications for Intravenous Fluid
▪ Replacement of extracellular fluid loss
– Haemorrhage
– Non-haemorrhage fluid loss
▪ Maintain fluid and electrolyte balance
– Nil by mouth
▪ Correct existing electrolyte or acid-base abnormality
- Hypernatremia / Hyponatraemia
– Acidosis / Alkalosis
▪ Provide a source of glucose
– Hypoglycaemia
Types of Intravenous Fluid
▪ Two main types
1. Colloids
2. Crystalloids
- Isotonic
- Normal Saline
- Balanced Solutions
- Hypertonic
- Hypotonic
Colloids
▪ AKA volume or plasma expanders
▪ Molecules are too large to pass through the semipermeable membranes so they expand intravascular volume but exerting colloid osmotic pressure and “pulling” fluid in.
▪ The molecules remain in the intravascular space longer, which leads to longer duration of action than crystalloids and less volume required.
Examples:
* Blood and plasma (the ideal colloid)
* Gelofusin
* Albumen
Crystalloids
▪ Crystalloid solutions contain water soluble electrolytes including sodium and chloride. They lack proteins and insoluble molecules.
▪ Distribute throughout ECF
▪ Classified according to tonicity
1. Isotonic – same concentration of electrolytes as plasma
2. Hypertonic – greater conc. of electrolytes than plasma
3. Hypotonic – lower conc. of electrolytes than plasma
Isotonic solutions
▪ Solutions that have the same tonicity as blood are considered isotonic
▪ Isotonic solutions distribute throughout the ECF
▪ Patient use:
– Hypovolaemic shock (bolus dose)
– Isotonic dehydration
▪ Examples:
– 0.9% NaCl (Normal saline)
– Hartmann’s solution (AKA Ringer’s lactate)
– Plasmalyte
Hypertonic solutions
▪ Hypertonic solutions have a greater tonicity than blood
▪ Draws water out of the cell and into the extracellular space
▪ Patient use:
– Hyponatremia
– Cerebral oedema
▪ Examples:-
– 3% NaCl
– 5% dextrose in 0.9% NaCl (normal saline)*
– 10% dextrose in water (D10W)*
- Dextrose rapidly taken up by cells shortly after infusion, thus decreasing tonicity (D10W becomes hypotonic)
Hypotonic solutions
▪ Hypotonic solutions have a tonicity less than blood plasma
▪ Fluids moves out of intravascular/interstitial space and into intracellular fluid.
▪ Patient use:
– Hypernatremia
– No longer recommended for routine maintenance due to risk of hyponatraemia
– Contraindicated in head injuries
▪ Examples:
– 0.45% NaCl (1/2 normal saline)
Vascular Access Devices
▪ Vascular Access Devices (VADs)
1. Peripheral Venous Cannulas
2. Central Venous Catheters
a. Central Venous Catheters
b. Peripherally Inserted Central Catheters (PICC)
c. Implanted Ports
Peripheral Venous Cannulas
▪ Clear plastic catheter sits over the hollow introducer needle.
▪ Venipuncture is performed and blood is seen in flashback chamber when vein is accessed.
▪ Catheter is then advanced off the introducer and into the vein.
Choosing an IV site
▪ Arm veins usually used.
▪ Potential IV sites are assessed for suitability:-
– Consider dominant hand (leave free)
– Away from flexion (wrist or antecubital fossa)
– Surgery side (left shoulder surgery
– site on right side)
– Injury (mastectomy, neuro deficit)
– Localised injury (oedema, cellulitis, skin grafts)
▪ Distal sites are preferred initially
– Allows for more proximal sites if access difficult
▪ Vein inspection
– Firm, elastic, engorged, round.
▪ Not hard, flat or bumpy
– Palpate to ensure no pulse
▪ Arteries sit close to veins
▪ Leg veins
– Only used if arm veins inaccessible.
– Mostly require a doctor to insert these.
▪ Scalp veins
– Use for infants due to ease of accessibility and reduced risk of dislocating needle.
Needless Intravenous Delivery Systems
▪ Many IVCs have an inbuilt safety device to reduce the risk of needlestick injury.
▪ The safety shield automatically engages as the tip of the needle passes through the hub of the catheter.
Central Venous Catheters – insertion and placement
▪ Inserted via the subclavian or internal jugular vein.
▪ Passed into superior vena cava using guidewire.
▪ Tip sits just above right atrium.
▪ Often have 3 lumens.
▪ Radio-opaque – confirmation X-ray must be performed before use.
Central Venous Catheters
▪ Used in acute and high dependency care.
▪ Central Venous Catheters (CVCs) allow:-
– Access for IV fluids, blood products, parenteral nutrition, medication
– Haemodynamic monitoring
– Blood sampling
▪ Different lumens allow for simultaneous infusions and monitoring.
▪ Patient considerations regarding CVCs
– Difficult venous access
– Irritating medications
– Haemodynamic monitoring
– Long term infusions
PICCs – insertion and placement
▪ Inserted into basillic or cephalic veins – (above antecubital fossa)
▪ Advanced over guidewire so tip reaches superior vena cava.
▪ Single or double lumen
▪ Radio-opaque – confirmation xray must be performed before use.
PICCs
▪ PICCs can remain longer than standard CVCs, as long as needed – up to 12 months.
▪ Patient considerations for PICCs
– Extended periods of medication administration
– Parenteral nutrition
– Chemotherapy (or other specific medications)
– Blood components
– Blood sampling
▪ Prevents repeated venepuncture – reduced infections.
Implanted Ports – insertion and placement
▪ Catheter tip in subclavian or jugular vein.
▪ Port placed in subcutaneous pocket in upper chest wall.
▪ No external parts of system are visible.
▪ Special needle used to access.
Implanted Ports
▪ A special needle is inserted through the skin and the rubber septum into the reservoir of the port.
▪ Disadvantage is use of needles to access every time.
▪ Used for long term intermittent therapy
– E.g. chemotherapy
Care of a CVCs (inc PICCs and Ports)
▪ Use 10ml syringe when flushing Smaller syringes should NEVER be used
– Larger syringes may not provide adequate pressure to clear micro sediment
– Flush using a pulsatile action 🡪 turbulent effect in IVC
– Flush before and after use
– medication/blood admin, blood sampling, when not in use to maintain patency
▪ Prevent blood sitting in catheter/line
– Could clot and stop function of device, may cause pulmonary embolism.
– Use positive pressure bungs, clamping, heparin lock
▪ Aseptic technique when changing dressings
▪ Clean technique when accessing bung (“scrub the hub”)
Complications of VADs
▪ IVCs
– Thrombosis, Air embolism, infection, bleeding, occulsion
▪ CVCs
– Pneumothorax, arrhythmias, catheter embolism, nerve/tendon damage.
▪ PICCs
– Infection, cellulitis, infiltration, sepsis
ALL CVCs must be confirmed by X-ray before use.
Equipment required to administer IV Fluids
▪ Fluid order
▪ Prescribed fluid
▪ Cannula
▪ Giving Set
▪ Cleanser/disinfectant
▪ Gloves
▪ Tape
▪ Dressing
▪ Armboard
▪ IV stand
▪ Injection tray
▪ Sharps Container
▪ Watch with second hand
Equipment – Fluid Order Chart
▪ Written order to indicate the type of fluid and the rate it should be infused (in 24 hours).
▪ As for any medication order it MUST include:
– Patient Identifiers, prescriber signature
Equipment - Fluid
▪ Correct fluid is determined by the fluid order chart (8 rights apply)
▪ Safety and Quality checks of the fluid bag:-
– Expiry date
– Type and strength of fluid
– Colour and clarity of IV fluid
– Check bag for leaks by gentle squeeze (condensation from outer bag is ok).
– Time label with time and initials may be attached (but must not obscure the details on the bag.
Two nurses check fluid against fluid order and patient.
Equipment - Cannula
- Different gauges
- attempt to use the smallest that can deliver the volume
- Size 14 and 16
- large bore, used in high risk surgery
- requires a large vein.
· Size 18 - used in trauma, blood transfusions, CT with contrast
· Size 20 - most commonly used. Ok for fluids and blood.
· Size 22 and 24 - used for smaller veins. In elderly or paediatric patients.
Equipment – Giving set
▪ Giving sets are the tubes that deliver the fluid – they have an inline drip chamber.
1. Gravity sets
2. Infusion pump sets
▪ Blood/inotropes
▪ Macrodrip giving rates
– Chamber 20 drops per ml
▪ Adults
– Chamber 60 drops per ml
▪ Paediatrics/elderly
Monitoring the flow rate – equipment and devices
▪ Burette
– A measured tube that goes ‘in-line’ between the giving set and the IV fluid.
– The IV fluid is clamped at the top, so only fluid in the burette can be infused at one time.
▪ Infusion pumps
– They regulate the rate of fluid to be infused in mls/hr.
– Use specific giving sets that fit the infusion pump.
– Pump alarms if air in line, if fluid has completed or if IV is blocked
▪ Syringe drivers
– Deliver small volumes of fluid
– 60 mls.
– Used for paediatrics, or certain medications.
Other equipment
▪ Cleanser/disinfectant
– Alchowipes, chlorhexidine, betadine (depending on facility policy)
▪ Gloves
– Standard precautions
▪ Tourniquet
– Reduce back flow of blood, distend veins to ease cannulation.
▪ Tape and Dressing
– To anchor cannula. Depends on policy, but transparent dressing common
▪ Armboard
– Only if required to stabilise joint to ease flow.
▪ Watch with second hand
– Needed to time the infusion rate.
Complications associated with IV fluid administration
▪ Complication associated with IV fluid administration can be divided into two:
1. Systemic complications
▪ Occur less frequently, but often more serious
2. Local complications
▪ Occur at or near the IV insertion site
Systemic IV complications – Fluid Overload
▪ Fluid Overload
– Too much IVF leads to hypervoleamia and increased CVP
▪ Signs & Symptoms
– Fine crackles, oedema, cough, restlessness, weight gain, dyspnoea, increased shallow RR, distended jugular veins.
▪ Cause
– Rapid infusion of IVF, renal, or cardiac disease.
– Can lead to acute pulmonary oedema (APO) – esp in elderly – circulatory overload
Systemic IV complications – Fluid Overload – Patients at risk
Patients at risk of Fluid Overload
▪ Paediatric patients
▪ Elderly patients
▪ Cardiac disease
– When heart is not pumping effectively, fluid backs up into lungs.
▪ Renal disease
– Kidneys are not functioning properly, cannot eliminate fluids at rate to match the infusion
Nursing Management (as always, start with DRSABC)
* Stop infusion, sit up (Fowlers), MET call if abnormal vital signs
* Focused cardiac and resp assessment. Provide reassurance.
* Apply oxygen and titrate to SpO2. Notify MO.
Systemic IV complications – Air Embolism
▪ Air Embolism
– Air enters vascular system and displaces blood. Rare.
▪ Signs and Symptoms
– Dyspnoea, cyanosis, hypotension, weak pulse, increased HR, LOC, chest/shoulder/low back pain.
▪ Cause
– The rate of entry of air as well as the volume of air. Most likely in cannulation of central veins.
▪ Treatment
– Clamp cannula, assess vitals, place on left side, head down position.
Systemic IV complications – Infection
▪ Infection
– Through IV solution or administration set.
▪ Signs and Symptoms
– Sudden temperature rise, tachycardia, hypotension, tachypnoea, decreased urine output (signs of sepsis).
▪ Cause
– Poor ANTT, contamination of IV fluids/medication. These increase if pt immunocompromised.
– Sepsis has 10-20% mortality rate
– Regarded as totally preventable
▪ Treatment
– Symptomatic treatment. Cultures of IV tubing/solution.
Local IV Complications – Infiltration
▪ Inadvertent administration of solution/medication into surrounding tissue. ▪ Oedema, swelling, inflammation ▪ Can occur when IV cannula dislodged from vein.
▪ Treatment
– Stop infusion
– Remove IVC
– Cold compress
Local IV Complications - Phlebitis
▪ Inflammation of vein due to chemical or mechanical irritation.
▪ Warm IV site or along vein, pain, swelling.
▪ Treatment
– Stop IV
– Warm compress to site
▪ Prevention
– Good ANTT
– Appropriate size cannula for vein
Local IV Complications - Extravasation
▪ Inadvertent administration of irritant into surrounding tissue
▪ Blistering, inflammation, necrosis
▪ Treatment
– Stop infusion
– Notify Doctor
– Follow extravasation protocol
– Antidote may be given
– Neurovascular observations
Local IV Complications - Haematoma
▪ Blood leaks into surrounding tissue.
▪ Due to needle slipping out of vein, or poor pressure when cannula removed.
▪ Bruise
▪ Treatment
– Remove IVC
– Pressure
Local IV Complications – Clotting and obstruction
▪ Blood clots from in IV tubing due to
– Kinked IV tubing
– Kink/bend in IVC
– Slow infusion rate
– not flushed regularly
– Empty/neglected IV bag
▪ Indicated by stopped or reduced flow
▪ If clot in IV line
– Stop infusion and start again with new set and line
▪ If clot in IVC
– KVO (keep vein open)
– maintenance fluids/regular flushes
– Doctor may inject a thrombolytic agent
Local IV Complications - Thrombophlebitis
▪ Clot and inflammation in the vein.
▪ Pain, redness, warmth, swelling. Immobility of extremity, fever.
▪ Treatment
– Stop IV
– Apply cold compress (reduces flow) then warm compress and elevation.
– Do not flush line - clots
Infection prevention measures
▪ Hand hygiene before contact with set, fluids, patient.
▪ Check IV containers for cracks/leaks, fluid for cloudiness
▪ Good anchoring of IV to prevent movement (stay in vein)
▪ Daily inspection of IV site.
▪ 8/24 checking of patency – N/S Flush
▪ “Scrub the hub” before accessing bung
▪ Change IVC as per facility policy – often 72 hours
– IVCs inserted in emergency/pre-hospital situations sooner.
▪ Replace fluid and giving set as per policy.
▪ IVC insertion sites should be rotated at least every 72-96 hours (depending on health service policy)
Monitoring the patient receiving IV fluids
▪ Doctors prescribe the fluid and the rate that it should be given.
– The rate is described as the number of hours it should run for – e.g. 4/24, 8/24,12/24 etc
▪ Nurses maintain the flow rate*.
– Determined by the amount of solution to be infused over an hour – drip rate.
– Drip rate is determined by the size of the lumen of the giving set.
▪ Various sizes, the most common being 20 or 60 drops per ml
– Important to ensure fluid is at appropriate rate and will not affect the fluid balance.
*Flow rate calculations will be covered in your workshop/lab this week.
Fluid and giving set changes
▪ Giving set changes
– Most facility policies state change every 72 hours
– Giving sets used for TPN, blood and some medications will require more frequency – 24hrs
▪ Fluid changes
– Occur at the end of an infusion – keep sterility of IV system
▪ Piggy-back infusions
– Whilst IV infusion taking place, another IV solution or medication can be added onto the existing fluid via the port.
IV administration - Blood
▪ Indications for giving blood
– Volume loss (trauma, surgery, haemorrhage), clotting abnormalities, anaemia
▪ Blood cross matching
– Patient must be cross matched to identify their blood group.
– Patients receive their own blood group – except in emergencies where type O- can be used.
– If patient is given the wrong blood – they may have a haemolytic reaction.
▪ Blood products
– There are different blood products including – whole blood, packed red cells, plasma, platelets, serum albumen, cryopreciptate.
Monitoring the flow rate
▪ Factors which may affect the flow rate include:-
– The height of the fluid in relation to the person
– The person’s position (inc limb position)
– The patency of the IV system – line and cannula
▪ Blocks, knots, kinks, clamps
– Blood pressure
▪ IV infusions should be checked hourly
– Patient movement, medication administration, equipment changes can all affect the IV rate.
IV administration - Blood Monitoring
▪ Due to the risk of haemolytic (transfusion) reaction, patients receiving blood require close monitoring.
▪ Blood checking procedure
– Blood must be given within 15 minutes of arrival on ward –
2 RNs must check patient (ID, blood type), blood pack (expiry date, unit ID number), prescription (fluid order, infusion rate, number of units).
▪ Blood administration
– Baseline set of vital signs
– Start infusion slowly – reactions occur in first 10-15 mins
▪ Blood monitoring
– Vital signs every 15 mins in first hour, then every 30 minutes.
– If changes in vital signs occur – stop infusion, advise NIC/MO
Facility policy may vary – check locally
IV Administration – Potassium
IV potassium must NEVER be given as a bolus (or push) - may cause potentially fatal cardiac arrhythmias.
- Potassium should not be given at a rate faster than 10 mmol/L per hour * Separate ampules of potassium should not be used and should not be added to IV bags.
- IV fluids with potassium have red writing on them as a warning.
