Comprehensive GCC nursing reference for IV fluid physiology, access, prescribing, electrolyte additives, complications, and regional context. Evidence-based to NICE CG174 and JCI standards.
Total body water is approximately 60% of body weight in adults (lower in females and obese patients).
Rich in potassium (K+), phosphate, magnesium. Separated from ECF by cell membrane Na+/K+ ATPase pump.
Normal plasma osmolality: 280–295 mOsm/kg. Tonicity describes the effect of a solution on cell volume.
| Tonicity | Osmolality | Cell Effect | Example |
|---|---|---|---|
| Isotonic | ~280–310 mOsm/kg | No change | 0.9% NaCl, Hartmann's |
| Hypotonic | <280 mOsm/kg | Cell swells | 0.45% NaCl, 5% Dextrose* |
| Hypertonic | >310 mOsm/kg | Cell shrinks | 3% NaCl, 50% Dextrose |
*5% Dextrose is isotonic in the bag but becomes hypotonic once glucose is metabolised.
Serum osmolality = 2 x [Na+] + [glucose mmol/L] + [urea mmol/L]. Effective osmolality excludes urea (freely permeable).
Net filtration = (Pc - Pi) - (πc - πi). Normally slight net outward filtration balanced by lymphatic drainage.
Key point: In sepsis with capillary leak, colloids leak into interstitium and worsen oedema — crystalloids preferred.
| Property | Crystalloids | Colloids |
|---|---|---|
| Composition | Water + electrolytes ± glucose | Water + large molecules (albumin, starches, gelatins) |
| Distribution | All ECF compartments | Mainly intravascular (initially) |
| Volume expansion per 1L | ~250 mL intravascular (0.9% NaCl) | ~700–800 mL (albumin) |
| Evidence (sepsis) | Preferred (SAFE, CRISTAL trials) | No mortality benefit; harm with HES in sepsis/AKI |
| Cost | Low | High (especially albumin) |
| Examples | 0.9% NaCl, Hartmann's, 5% Dextrose | 4% Albumin, Gelofusine, Voluven (HES) |
Na+ 154 mmol/L, Cl- 154 mmol/L. Isotonic (308 mOsm/L). Commonly used but NOT physiologically balanced.
Indications: Hypochloraemic alkalosis, head injury (avoid hypotonic solutions), medication dilution per SPC, DKA (first fluid in many protocols).
Na+ 131, K+ 5, Ca2+ 2, Cl- 111, Lactate 29 mmol/L. Osmolality 278 mOsm/L. Balanced, most physiological crystalloid.
Indications: Resuscitation, peri-operative fluids, bowel surgery, general maintenance. Avoid in hyperkalaemia (contains K+).
Glucose 50g/L, 278 mOsm/L. Isotonic in bag — becomes hypotonic once glucose metabolised. No electrolytes.
Distributes across ALL body compartments (ICF + ECF) — only 1/14 remains intravascular. Not for volume expansion.
Indications: Hypoglycaemia, free water replacement, drug dilution (specific drugs), providing glucose in starvation.
Na+ 30 mmol/L, Cl- 30 mmol/L, Glucose 40g/L. Hypotonic (284 mOsm/kg).
Indications: Paediatric maintenance, providing some Na+ with glucose for patients who cannot eat. Not suitable for resuscitation.
Available as 1.8%, 3%, 7.5% NaCl. Highly concentrated — pulls water from ICF to ECF/intravascular.
Human Albumin Solution (HAS): 4–5% for volume, 20–25% for oncotic pressure. Evidence-based use in cirrhosis/SBP (NICE), large-volume paracentesis.
Gelofusine (Succinylated Gelatin): Synthetic colloid. Rarely indicated. Anaphylaxis risk. Limited evidence.
Voluven (HES — Hydroxyethyl Starch): CONTRAINDICATED in sepsis, AKI, ICU patients (VISEP, 6S, CHEST trials — increased mortality and AKI). Use is highly restricted globally.
| Gauge | Colour | Flow Rate | Primary Indications |
|---|---|---|---|
| 14G | Orange | ~270 mL/min | Rapid fluid resuscitation, massive transfusion, major trauma. Largest peripheral cannula. |
| 16G | Grey | ~180 mL/min | Blood transfusion, major surgery, large-volume fluid therapy. |
| 18G | Green | ~90 mL/min | Standard adult IV access, CT contrast injection, blood products. Most common choice. |
| 20G | Pink | ~60 mL/min | Standard adult, paediatrics, patients with fragile veins. Good for most medications. |
| 22G | Blue | ~36 mL/min | Elderly patients, difficult IV access, small veins. Slow infusions only. |
| 24G | Yellow | ~22 mL/min | Neonates, fragile/small veins, very small paediatrics. |
Larger gauge number = smaller cannula = lower flow rate. Use largest cannula appropriate for clinical need and vein size.
Assess ALL peripheral cannulas every shift. Document score. Remove if score ≥ 2.
Peripheral cannulas should be replaced every 72–96 hours or sooner if clinically indicated. Remove when no longer required — minimum dwell time reduces infection risk.
For full detail refer to the Central Line & VAD Guide. Key points:
Indication: Haemodynamic instability — shock (septic, hypovolaemic, haemorrhagic, anaphylactic).
Passive Leg Raise (PLR): Gold standard for dynamic assessment. Raise legs to 45° for 1 minute (autotransfusion ~300 mL). If CO/BP increases >10% — fluid responsive. Reversible test — safe in cardiac/renal patients.
Pulse Pressure Variation (PPV): Only valid in mechanically ventilated patients in sinus rhythm with no spontaneous breaths. PPV >13% suggests fluid responsiveness. Requires arterial line for accurate measurement.
For adults who cannot meet needs enterally. Target over 24 hours:
| Parameter | Daily Requirement | Notes |
|---|---|---|
| Water | 25–30 mL/kg/day | Reduce if fluid overloaded, renal failure, SIADH. Increase if fever, losses. |
| Sodium | 1 mmol/kg/day | Approx 50–100 mmol/day. Excess Na+ causes fluid retention. |
| Potassium | 1 mmol/kg/day | Approx 40–80 mmol/day. Requires monitoring and supplementation in bags or separate infusion. |
| Chloride | 1 mmol/kg/day | Provided alongside Na/K salts. |
| Glucose | 50–100 g/day | Prevents starvation ketosis and provides minimal caloric intake. |
Standard regimen example: 1L 0.18% NaCl/4% Dextrose + 20 mmol KCl over 8 hours × 3 bags in 24 hours. Adjust based on electrolytes, weight, clinical status.
Address ongoing losses beyond normal maintenance. Calculate and replace:
Review IV fluid need daily. Stop when patient can tolerate enteral fluids/feeds. Perform a fluid balance audit — input vs output — every 24 hours.
| Formula | Calculation |
|---|---|
| mL/hour | Volume (mL) ÷ Time (hours) |
| Drops/minute (gravity) | [Volume (mL) × Drop factor] ÷ [Time (minutes)] |
| Time to complete (hours) | Volume (mL) ÷ Rate (mL/hr) |
Drop factors: Blood administration sets = 15 drops/mL | Standard giving sets = 20 drops/mL | Paediatric/Burette = 60 drops/mL | Macro drip (some countries) = 10 drops/mL
| Bag | KCl Content | Concentration |
|---|---|---|
| 0.9% NaCl 1L + KCl | 20 mmol | 20 mmol/L |
| 0.9% NaCl 1L + KCl | 40 mmol | 40 mmol/L |
| 0.18% NaCl/4% Dex + KCl | 20 mmol | 20 mmol/L |
Mild (3.0–3.5 mmol/L): Oral KCl preferred if patient can tolerate
Moderate (2.5–3.0 mmol/L): IV via peripheral at 10 mmol/hr with monitoring
Severe (<2.5 mmol/L or symptomatic): IV via central line, continuous cardiac monitoring, HDU/ICU setting
| Mg Level | Effect | Action |
|---|---|---|
| 0.7–1.0 mmol/L | Normal | Continue |
| 1.5–2.5 mmol/L | Therapeutic (eclampsia) | Monitor |
| 2.5–3.5 mmol/L | Loss of patellar reflex | Stop infusion |
| >5 mmol/L | Respiratory arrest, cardiac arrest | Calcium gluconate IV + resuscitation |
Hypophosphataemia (<0.8 mmol/L) — causes: refeeding syndrome, DKA, malnutrition, alcoholism, prolonged TPN without phosphate.
Risk: >5 days starvation, malnourished patients, chronic alcohol misuse. Introduce nutrition gradually. Monitor K+, Mg2+, PO4- closely. IV thiamine before feeding in at-risk patients.
| Feature | Infiltration | Extravasation |
|---|---|---|
| Definition | Non-vesicant fluid leaks into surrounding tissue | Vesicant/irritant drug leaks into tissue — causes damage |
| Cause | Dislodged cannula, venous fragility | Same + high-risk drugs |
| Tissue damage | Minimal — resolves spontaneously | Severe — necrosis, blistering, permanent damage |
| Pain | Often minimal | Often painful, burning sensation |
| Blanching | Possible | Yes — blanched, cool skin |
| Management | Stop infusion, elevate, warm compress | Stop + aspirate + antidote + photograph + document |
The following drugs cause significant tissue damage if extravasated:
GCC countries experience extreme heat (summer temperatures 40–50°C ambient, vehicle interiors 60–80°C). This affects IV fluid integrity significantly.
Emergency vehicles must have insulated drug storage. Check ambulance bag temperatures during summer. Rotate stock frequently. Do not administer fluids that have been left in a hot vehicle.
A significant proportion of GCC patients observe Ramadan fasting — sunrise to sunset. IV therapy during fasting requires cultural and religious sensitivity.
The Joint Commission International (JCI) mandates that concentrated potassium chloride ampoules be removed from all ward areas and restricted to pharmacy and ICU/HDU with appropriate monitoring.
IV therapy contributes significantly to needlestick injury (NSI) risk. GCC healthcare workers face elevated risk due to high IV therapy workload, high patient-to-nurse ratios, and inconsistent use of safety-engineered devices.
Certified Registered Nurse Infusion (CRNI) — awarded by the Infusion Nurses Society (INS, USA). Growing recognition in GCC as a valued advanced nursing credential.
| Topic | GCC Consideration | Action |
|---|---|---|
| KCl storage | JCI mandate — ward stock removal | Use pharmacy-prepared bags only; escalate if concentrated KCl on ward |
| Smart pumps | BD Alaris / B Braun most common | Use drug library; document all soft-limit overrides |
| IV fluid storage | Extreme heat — cold chain essential | Pharmacy storage 15–25°C; discard heat-exposed bags |
| Ramadan | Widespread fasting practice | Discuss with patient; schedule non-essential glucose IVs around fasting; document |
| Needlestick | High IV workload, inconsistent safety devices | Advocate for safety needles; report all NSI; PEP within 2hrs |
| CRNI certification | Growing GCC recognition | Consider for career development — INS website for eligibility |
| CLABSI | JCI-monitored metric in GCC hospitals | Maximal sterile barrier, scrub the hub, daily line review |