Choose and prescribe IV fluids as drugs (balanced crystalloids for most), and manage the electrolyte emergencies of the ICU: hypo- and hypernatraemia with safe correction limits, hyperkalaemia, hypokalaemia, and calcium, magnesium and phosphate disorders including refeeding syndrome.
6 topics
- 01
IV fluids: choice, dose and stewardship
Treat fluids as drugs with four phases: resuscitation, optimisation, stabilisation, de-escalation. Balanced crystalloids are reasonable default resuscitation fluids; saline for TBI and hypochloraemia; albumin selectively; never starches.
5 stepsAlgorithmNew - 02
Hyponatraemia
Treat symptoms, not the number: severe symptoms get 3% saline boluses immediately. Then classify by osmolality, volume status and urine studies. Limit correction to 10 mmol/L in 24 h (8 if high risk of osmotic demyelination) and re-lower if overshooting.
7 stepsAlgorithm1 dosesNew - 03
Hypernatraemia
Na+ > 145 mmol/L usually means water loss plus inability to drink. Restore volume first if shocked, then replace the free-water deficit plus ongoing losses, lowering Na+ by about 10 mmol/L/day in chronic cases.
5 stepsAlgorithmNew - 04
Hyperkalaemia
Five steps (UKKA): protect the heart with IV calcium if ECG changes, shift K+ into cells with insulin-glucose (± salbutamol), remove K+ (binders, diuresis, dialysis), monitor glucose and K+, and prevent recurrence.
6 stepsAlgorithm3 dosesNew - 05
Hypokalaemia
Replace potassium safely (≤ 10 mmol/h peripherally, ≤ 20 mmol/h centrally with monitoring), correct magnesium, and look for the cause (GI loss, diuretics, insulin, β-agonists, refeeding, RTA, hyperaldosteronism).
5 stepsAlgorithm1 dosesNew - 06
Calcium, magnesium, phosphate and refeeding syndrome
Use ionised calcium in the ICU. Treat symptomatic hypocalcaemia with IV calcium; replace magnesium early. Identify refeeding risk before feeding: start low, give thiamine, and check phosphate, potassium and magnesium every 12 h for 3 days.
7 stepsAlgorithm2 dosesNew
Drugs in this module
Doses written for this module's context. The same drug may read differently in another module.
Balanced crystalloid (Ringer's lactate, Plasma-Lyte)
Isotonic crystalloid
Balanced crystalloid (Ringer's lactate, Plasma-Lyte)
Isotonic crystalloid
- Indications
- Default resuscitation and replacement fluid in most ICU patients.
- Adult dose
- Resuscitation boluses 250-500 mL over 15-30 min, reassessing after each; replacement matched to measured losses.
- Preparation (India)
- RL 500 mL bottles/bags (Na 130, K 4, Ca 2.7 mmol/L, lactate 28); Plasma-Lyte A/148 (Na 140, K 5, Mg 1.5, acetate 27, gluconate 23).
- Cautions
- Mildly hypotonic (RL ~273 mOsm/L): prefer 0.9% saline in raised ICP/severe TBI; volume overload.
3% sodium chloride
Hypertonic crystalloid
3% sodium chloride
Hypertonic crystalloid
- Indications
- Symptomatic (moderate-severe) hyponatraemia; raised ICP.
- Adult dose
- Severe symptoms: 150 mL (or 2 mL/kg) over 20 min, repeat up to 2-3 times checking Na+ between, aiming for +5 mmol/L in the first hours. Limit rise to 10 mmol/L in 24 h (8 if high ODS risk).
- Preparation (India)
- 3% NaCl (513 mmol/L) bottles available; or locally prepared – confirm recipe and label clearly.
- Cautions
- Overcorrection and osmotic demyelination; volume overload; peripheral phlebitis with prolonged infusion (short bolus via peripheral line is acceptable).
Calcium gluconate 10%
Electrolyte / membrane stabiliser
Calcium gluconate 10%
Electrolyte / membrane stabiliser
- Indications
- Hyperkalaemia with ECG changes; symptomatic hypocalcaemia; calcium channel blocker toxicity; magnesium toxicity.
- Adult dose
- Hyperkalaemia: 30 mL of 10% IV over 10 min (≈ 6.8 mmol Ca2+), repeat if ECG changes persist. Hypocalcaemia: 10-20 mL over 10 min, then infusion 0.5-1.5 mg/kg/h elemental calcium.
- Preparation (India)
- 10 mL ampoules of 10% (0.22 mmol/mL Ca2+).
- Cautions
- Do not mix with bicarbonate (precipitates); caution with digoxin toxicity; extravasation injury.
Insulin + glucose
Potassium shift
Insulin + glucose
Potassium shift
- Indications
- Hyperkalaemia K+ ≥ 6.0 mmol/L.
- Adult dose
- Soluble insulin 10 units with 25 g glucose IV over 15 min (e.g. 50 mL of 50% dextrose, or 250 mL 10%). If pre-treatment glucose < 7 mmol/L (126 mg/dL), follow with 10% glucose 50 mL/h for 5 h.
- Preparation (India)
- Regular (soluble) insulin 40 IU/mL vials are common in India; U-100 vials also exist; check the strength.
- Cautions
- Hypoglycaemia (most common up to 6 h; monitor glucose 0, 30, 60, 90, 120, 180, 240, 300, 360 min), especially in CKD.
Salbutamol (nebulised)
β2-agonist
Salbutamol (nebulised)
β2-agonist
- Indications
- Adjunct for hyperkalaemia K+ ≥ 6.5 mmol/L.
- Adult dose
- 10-20 mg nebulised (as additional, not sole therapy).
- Cautions
- Tachycardia; less effective on β-blockers; caution in ischaemic heart disease.
Potassium chloride
Electrolyte
Potassium chloride
Electrolyte
- Indications
- Hypokalaemia; metabolic alkalosis.
- Adult dose
- Peripheral: up to 10 mmol/h (40 mmol/L). Central line with cardiac monitoring: up to 20 mmol/h (max 40 mmol/h in life-threatening). Oral 20-40 mmol 2-3 times daily.
- Preparation (India)
- 15% KCl 10 mL ampoule = 20 mmol. Premixed bags preferred. Never give undiluted or as a bolus.
- Cautions
- Fatal if pushed; reduce in AKI/oliguria; correct Mg2+.
Magnesium sulphate
Electrolyte
Magnesium sulphate
Electrolyte
- Indications
- Hypomagnesaemia; refractory hypokalaemia/hypocalcaemia; torsades; eclampsia; severe asthma.
- Adult dose
- Hypomagnesaemia: 2 g (8 mmol) IV over 15-60 min (over 1-2 min in torsades), then up to 8 g/24 h guided by levels.
- Preparation (India)
- 50% w/v (2 mmol/mL; 1 g in 2 mL); dilute for infusion.
- Cautions
- Reduce dose in renal failure; loss of reflexes, respiratory depression if toxic (antidote calcium).
Potassium / sodium phosphate
Electrolyte
Potassium / sodium phosphate
Electrolyte
- Indications
- Hypophosphataemia, especially refeeding.
- Adult dose
- Moderate (0.3-0.6 mmol/L): 0.3-0.5 mmol/kg IV over 6-12 h; severe (< 0.3): 0.5 mmol/kg (max ~50 mmol) over 8-12 h; recheck.
- Preparation (India)
- Availability of IV phosphate varies in India; oral phosphate (sodium/potassium phosphate) may be the only option.
- Cautions
- Hypocalcaemia, metastatic calcification; potassium load; reduce in AKI.