How to manage a patient with hypernatremia and a clavicle fracture?

Management of Hypernatremia in a 79-Year-Old with Clavicle Fracture

For this 79-year-old patient with a sodium level of 152 mmol/L following a fall and clavicle fracture, you should correct the hypernatremia with hypotonic fluids (0.45% NaCl or D5W) at a rate not exceeding 10-15 mmol/L per 24 hours, while simultaneously managing the clavicle fracture conservatively with a sling or figure-of-eight brace. 1, 2

Immediate Assessment Required

Determine the volume status and underlying cause of hypernatremia:

• Check for signs of dehydration: dry mucous membranes, decreased skin turgor, orthostatic hypotension, tachycardia 1, 3
• Assess neurological status: confusion, altered mental status, weakness, seizures 2, 4
• Review medications that may contribute to hypernatremia 3
• Measure urine osmolality and urine sodium to differentiate between water loss versus sodium gain 5, 4
• Calculate fluid deficit using: Water deficit (L) = 0.5 × body weight (kg) × [(current Na/140) - 1] 4

Hypernatremia Correction Strategy

For this moderate hypernatremia (152 mmol/L), implement the following approach:

Fluid Replacement

• Use hypotonic fluids: 0.45% NaCl (half-normal saline) or D5W (5% dextrose in water) as primary replacement fluids 1, 2
• Avoid isotonic saline (0.9% NaCl) as this will worsen hypernatremia, particularly if the patient has any degree of renal concentrating defect 1
• Administer fluids orally if the patient can tolerate; otherwise use intravenous route 4

Correction Rate

• Target reduction of 10-15 mmol/L per 24 hours to avoid cerebral edema 1, 3
• For this patient with Na 152 mmol/L, aim to reduce to approximately 140 mmol/L over 24-36 hours 1
• Never correct faster than 12 mmol/L per day in chronic hypernatremia (>48 hours duration) 3
• If hypernatremia developed acutely (<48 hours), faster correction up to 1 mmol/L/hour may be acceptable if severely symptomatic 1

Monitoring Protocol

• Check serum sodium every 4-6 hours initially during active correction 4
• Monitor neurological status closely for signs of cerebral edema (worsening confusion, seizures) 1, 4
• Track fluid balance, daily weights, and urine output 1
• Measure serum potassium, chloride, and bicarbonate regularly 1

Clavicle Fracture Management

The clavicle fracture should be managed conservatively in most cases:

• Apply a simple arm sling or figure-of-eight brace for comfort and immobilization
• Provide adequate analgesia (acetaminophen preferred in elderly; avoid NSAIDs if renal concerns)
• Most clavicle fractures heal with conservative management in 6-12 weeks
• Surgical intervention only if significantly displaced, open fracture, or neurovascular compromise

Critical Pitfalls to Avoid

Do not correct chronic hypernatremia too rapidly - this causes cerebral edema, seizures, and permanent neurological injury as brain cells have synthesized intracellular osmolytes to adapt to hyperosmolar conditions 1, 4

Do not use isotonic saline (0.9% NaCl) in patients with hypernatremia, especially if any renal concentrating defect exists, as this will exacerbate the hypernatremia 1

Do not delay correction - prolonged hypernatremia is associated with increased hospital stay and mortality in elderly patients 3

Do not overlook the fall risk - hypernatremia at this level (152 mmol/L) is associated with cognitive impairment and increased fall risk, which likely contributed to the initial fall and fracture 3

Special Considerations for Elderly Patients

This 79-year-old patient is at particularly high risk:

• Elderly patients have impaired thirst mechanisms and reduced access to water 2, 3
• Nursing home residents and those with cognitive impairment or restricted mobility are especially vulnerable 3
• Hypernatremia in this population is associated with high morbidity and mortality 5, 3
• Ensure adequate ongoing free water intake after correction to prevent recurrence 4

Underlying Cause Investigation

While treating, identify the cause:

• Most common in elderly: inadequate water intake due to impaired thirst or restricted mobility 3
• Consider diabetes insipidus if urine osmolality is inappropriately low (<300 mOsm/kg) 2, 4
• Review for excessive sodium administration (IV fluids, medications) 6
• Assess for excessive water losses (diarrhea, fever, hyperventilation) 5, 4