Very high or very low potassium (roughly above 6.0 or below 3.0 mEq/L) can cause fatal dysrhythmias — start cardiac monitoring and notify the provider now.
Before you read
Test yourself first: 3 questions
Question 1 of 3
Which lab result requires the nurse to notify the provider immediately?
Answer: A. An INR of 6.0 is critically high and confers serious bleeding risk. The other values are normal or near-normal.
Question 2 of 3
Which lab value is a critical result the nurse reports immediately?
Answer: A. A glucose of 38 mg/dL is critically low (severe hypoglycemia) and needs immediate treatment and reporting. The other values are within normal limits.
Question 3 of 3
Before administering cisplatin, which laboratory value is most important for the nurse to review to reduce the risk of toxicity?
Answer: A. Cisplatin is nephrotoxic, so renal function must be assessed before administration. An elevated serum creatinine indicates impaired kidney function and increased risk of further injury, and the dose may need to be held or adjusted. The other values are monitored but are not the primary safety check for cisplatin nephrotoxicity.
Keep the streak going with more questions like these, each with a full rationale.
What is lab values by urgency?
Grading a value before acting keeps the answer safe. A value that is abnormal but expected for the patient's condition needs monitoring, a worsening value needs assessment and a report, and a critical value needs action and provider notification now. Critical (panic) values are those that can threaten life within hours, and facility policy sets how fast they must reach the provider.
Key points to remember
- Abnormal but expected: outside the normal range but fits the diagnosis and is stable (for example, a high creatinine in chronic kidney disease) — document and monitor.
- Concerning: newly abnormal or trending the wrong way — reassess the patient and report it.
- Critical: can cause harm within hours — act per protocol, notify the provider promptly, and read back any value given by phone.
- Deadly: can cause death within minutes, such as a potassium high enough to cause dysrhythmias — act now and stay with the patient.
- Assess the patient before acting on a single value unless the value itself is life-threatening; a result that does not fit the picture may be a lab error, such as a high potassium from a hemolyzed sample.
- Know the anchor ranges cold: potassium 3.5–5.0 mEq/L, sodium 135–145 mEq/L, pH 7.35–7.45, PaCO2 35–45 mmHg, HCO3 22–26 mEq/L, platelets 150,000–400,000/mm³.
Nursing priorities
- Compare the value with the normal range, the patient's baseline and the trend.
- Look for findings that match the value: ECG changes with potassium, confusion with sodium, bleeding with low platelets.
- Report critical values to the provider right away using SBAR, and document the time, who was notified and the response.
- Hold medicines that would worsen the value (potassium supplements in hyperkalemia, anticoagulants with a high INR) and ask for orders.
- Ask for a repeat sample when a result does not match the patient's condition.
Labs & values
Red flags: report now
- Very high or very low potassium (roughly above 6.0 or below 3.0 mEq/L) can cause fatal dysrhythmias — start cardiac monitoring and notify the provider now.
- Platelets under 40,000/mm³ bring a high risk of serious bleeding — start bleeding precautions and report.
- Any critical value with a change in condition (new confusion, chest pain, bleeding) is an emergency.
References
Clinical references for this topic
