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Renal Exam

Fluid Status

March 4th, 2023


Assessing a patient's fluid status can often be very difficult, and relies on multiple different clinical measurements.
An accurate fluid status assessment can be useful for assessing for dehydration or overload, and for titrating a patient's fluid management - whether that be by giving more fluid or removing fluid through diuresis or dialysis.


  • Look For

  • Abnormal obs - tachycardia, hypotension
  • Fluid balance chart - negative fluid balance, oliguria
  • Weight loss - an acute decrease in weight may indicate short-term change in fluid status
  • Dry mucous membranes - especially the tongue
  • Sunken eyes
  • Increased capillary refill time (>2 seconds)
  • Weak radial pulse
  • Decreased skin turgor - pinch a fold of skin on the patient's arm and then release it. Decreased skin turgor is present if the fold takes an abnormal time to return to its normal contour.
  • Causes of Dehydration

  • Poor fluid intake
  • Fluid loss - diarrhoea, vomiting, sweating, diuresis (diabetes, diuretics)
  • Complications

  • Seizures
  • Renal failure
  • Hypovolaemic shock

Fluid Overload

  • Look For

  • Hypertension
  • Positive fluid balance in obs chart
  • Weight gain - look for a recent weight and compare to current weight
  • Bounding pulses
  • Raised JVP
  • Presence of S3 (gallop rhythm)
  • Crackles on lung field auscultation
  • Ascites - shifting dullness or fluid thrill
  • Pitting oedema to the sacrum and lower limbs, as well as elsewhere in the body in severe hypervolaemia
  • Causes of Fluid Overload

  • Excessive IV fluids
  • Heart failure
  • Renal failure
  • Hepatic cirrhosis
  • Pregnancy
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