Being able to assess the fluid status of a patient is a key skill that you will regularly do as a junior doctor. It involves assessing if a patient is hypovolaemic, euvolaemic or hypervolaemic and then using this information to guide your clinical management going forwards.
Factors to consider before examining the patient
Read the notes and take a history!
- Why is this patient in hospital?
- Reasons for admission which may affect fluid requirements include:
- Surgical patients: pre or post op, NBM?
- GI losses – vomiting, diarrhoea, stoma output
- What is their relevant past medical history?
- Renal disease
- Heart failure
- Pre or post op
- Drug history
- Drugs which can alter bowel habit
- E.g. antibiotics (diarrhoea), opioids (constipation)
- Other factors
- Active bleeding?
- Vomiting: how much, how often, blood?
- Stools: how much, how often, blood?
- Urine output
- Light-headedness / dizziness
- Eating / drinking over the last day or so
- Are they already receiving IV fluids?
- Is there a fluid restriction in place?
- Age of the patient
- Obvious oedema from end of bed
- Shortness of breath?
- Colour – pallor?
- Anything around the bed space – IV fluids, catheter, stoma, surgical drains etc.
- Look in patient notes for fluid balance chart and Bristol stool chart – not always filled out but very helpful when it is
- There may also be a daily weight chart – also very helpful!
- Use this time to check medications if you haven’t already too
- Inspect: oedema, peripheral stigmata of disease
- Palpate the radial pulse: volume and rate
- Capillary refill time: should be <2
- Check blood pressure – often a late sign but still helpful
- Lying and standing BP
- Assess skin turgor – gently pinch a fold of skin for a few seconds, assess how long it takes to return to normal
- Ask patient to open mouth to assess mucous membranes
- Look to eyes for pallor and sunken eyes
- Check JVP: if >3cm consider fluid overload
- Respiratory rate
- Listen over 4 heart valves: added S3 gallop rhythm might be heard in fluid overload
- Auscultate lungs – coarse crackles may indicate pulmonary oedema
- Assess for sacral oedema at bottom of back
- Assess for ascites: shifting dullness
- Assess for peripheral oedema: if so, how far up does it go?
- Look to catheters, stomas, surgical drains
- Assess output volume, colour and type of output
- FBC: drop in Hb suggests haemorrhage, raised haemocrit suggest dehydration
- Urea/creatinine: raised in dehydration, urea raised in upper GI haemorrhage
- Sodium: raised in dehydration, low in fluid overload (dilutional)
- Chest X-ray: pulmonary oedema
- Echocardiogram: heart failure
- Bladder scan: urinary retention