Hyperkalemia laboratory findings: Difference between revisions
Jump to navigation
Jump to search
No edit summary |
|||
| Line 10: | Line 10: | ||
In a patient who does not have a risk for hyperkalemia, repeating the blood test is indicated before taking any actions unless changes are present on [[electrocardiography]] | In a patient who does not have a risk for hyperkalemia, repeating the blood test is indicated before taking any actions unless changes are present on [[electrocardiography]] | ||
==Laboratory Findings== | ==Laboratory Findings== | ||
*The first step in diagnosing hyperkalemia is to exclude [[pseudohyperkalemia]] by repeating the blood test. | |||
{| class="wikitable" | {| class="wikitable" | ||
| Line 24: | Line 25: | ||
|>8.5mEq/L | |>8.5mEq/L | ||
|} | |} | ||
===Initial tests=== | ===Initial tests=== | ||
*Complete blood count (CBC) | *Complete blood count (CBC) | ||
| Line 54: | Line 54: | ||
*Serum uric acid and phosphorus assays (tumor lysis syndrome) | *Serum uric acid and phosphorus assays (tumor lysis syndrome) | ||
*Serum [[Creatine kinase|creatinine phosphokinase]] (CPK) and calcium measurements and urine [[myoglobin]] test (crush injury or rhabdomyolysis) | *Serum [[Creatine kinase|creatinine phosphokinase]] (CPK) and calcium measurements and urine [[myoglobin]] test (crush injury or rhabdomyolysis) | ||
===Psudeohyperkalemia=== | ===Psudeohyperkalemia=== | ||
*Defined as the release of potassium from cells after their breakdown. Most commonly seen during blood collection, so it's required to repeat blood test in patients with a transient rise in potassium without any risk factors. | *Defined as the release of potassium from cells after their breakdown. Most commonly seen during blood collection, so it's required to repeat blood test in patients with a transient rise in potassium without any risk factors. | ||
*Other causes include | *Other causes include | ||
**[[Coagulation|Clotting]] increases release of potassium from [[Platelet|platelets]] | **[[Coagulation|Clotting]] increases release of potassium from [[Platelet|platelets]] | ||
**In patients with history of | **In patients with the history of leukemia where the WBC count is >120,000/microL the potassium is raised to cell fragility | ||
**Hereditary (familial) forms of [[pseudohyperkalemia]] | **Hereditary (familial) forms of [[pseudohyperkalemia]] | ||
Revision as of 19:09, 13 July 2018
<figure-inline><figure-inline><figure-inline><figure-inline> </figure-inline></figure-inline></figure-inline></figure-inline> |
Resident Survival Guide |
|
Hyperkalemia Microchapters |
|
Diagnosis |
|---|
|
Treatment |
|
Case Studies |
|
Hyperkalemia laboratory findings On the Web |
|
American Roentgen Ray Society Images of Hyperkalemia laboratory findings |
|
Risk calculators and risk factors for Hyperkalemia laboratory findings |
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-In-Chief: Priyamvada Singh, M.B.B.S. [2] ; Aditya Ganti M.B.B.S. [3]
Overview
In a patient who does not have a risk for hyperkalemia, repeating the blood test is indicated before taking any actions unless changes are present on electrocardiography
Laboratory Findings
- The first step in diagnosing hyperkalemia is to exclude pseudohyperkalemia by repeating the blood test.
| Grade | Potassium level |
|---|---|
| Mild | 5-7mEq/L |
| Moderate | 7-8.5mEq/L |
| Severe | >8.5mEq/L |
Initial tests
- Complete blood count (CBC)
- Metabolic profile .[1]
- Urine potassium, sodium, and osmolality [2]
| Hyperkalemia | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Exclude psuedohyperkalemia by repeating the blood test | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Acute rise in potassium | Persistent hyperkalemia | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Increase release of K+ from cells Trauma,radiation therapy, DKA, metabolic acidosis | Decreased urinary excreation of K+ rule out aldosterone deficency 24 hr urine K+ excreation | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Cause specific
- Blood glucose In patients with history of diabetes mellitus
- Digoxin level
- Arterial or venous blood gas (acidosis)
- Urinalysis (renal insufficiency)
- Serum cortisol and aldosterone levels (mineralocorticoid deficiency)
- Serum uric acid and phosphorus assays (tumor lysis syndrome)
- Serum creatinine phosphokinase (CPK) and calcium measurements and urine myoglobin test (crush injury or rhabdomyolysis)
Psudeohyperkalemia
- Defined as the release of potassium from cells after their breakdown. Most commonly seen during blood collection, so it's required to repeat blood test in patients with a transient rise in potassium without any risk factors.
- Other causes include
- Clotting increases release of potassium from platelets
- In patients with the history of leukemia where the WBC count is >120,000/microL the potassium is raised to cell fragility
- Hereditary (familial) forms of pseudohyperkalemia
References
- ↑ Kogika MM, de Morais HA (2017). "A Quick Reference on Hyperkalemia". Vet. Clin. North Am. Small Anim. Pract. 47 (2): 223–228. doi:10.1016/j.cvsm.2016.10.009. PMID 27939860.
- ↑ Conte G, Dal Canton A, Imperatore P, De Nicola L, Gigliotti G, Pisanti N; et al. (1990). "Acute increase in plasma osmolality as a cause of hyperkalemia in patients with renal failure". Kidney Int. 38 (2): 301–7. PMID 2402122.