Hypophosphatemia in Critical Care

Summary:
In this episode, we spotlight a stealthy ICU disruptor — hypophosphataemia. Based on a 2024 narrative review in the Journal of Clinical Medicine, we explore why phosphate matters, how it goes missing in critically ill patients, and why you should care even when it’s just “a little low.”

What’s Covered:

• The vital role of phosphate in energy, oxygen delivery, and muscle function

• Why hypophosphataemia affects 20–80% of ICU patients

• Clinical consequences, from muscle weakness to respiratory failure, arrhythmias, and delirium

• Common causes: refeeding, DKA, diuretics, malnutrition, and sepsis

• Replacement options — and why there's no universal guideline

• When to go IV, when oral might suffice, and what risks to watch for

Key Takeaways:

• Don’t overlook mild phosphate drops — they’re not always benign

• Severe hypophosphataemia (<0.4 mmol/L) can be life-threatening

• Consider protocols for screening and replacement in high-risk ICU patients

• More research is needed, but clinical awareness matters now

Final Thought:
Phosphate might be the quiet ninja of the ICU — when it vanishes, chaos isn’t far behind. Check your labs, trust your gut, and give phosphate the respect it deserves.

Hypophosphataemia in Critical Illness: A Narrative Review