Heparin-induced hyperkalemia

Heparin-induced hyperkalemia, can LMWH cause hyperkalemia? A systematic review

Hyperkalemia, an elevated blood potassium concentration exceeding 5.0 mEq/L, is associated with adverse outcomes and is frequently observed in hospitalized patients. Drug-induced hyperkalemia accounts for a significant proportion of cases, with heparin, commonly used for venous thrombosis prevention, suspected to contribute, though less recognized than other heparin-related side effects. Both unfractionated heparin (UFH) and low molecular weight heparin (LMWH) have been implicated in inducing hyperkalemia, primarily through the suppression of aldosterone levels and modulation of angiotensin II receptors. This systematic review examines the relationship between heparin, particularly LMWH, and hyperkalemia. Thirteen studies involving 1407 patients were analyzed. Findings indicated a lack of highquality evidence, with no significant increase in potassium levels associated with LMWH use. LMWH did not exhibit a dose-response relationship with hyperkalemia incidence. Additionally, mechanisms underlying the hypothetical LMWHinduced hyperkalemia remained inconclusive. While this suggests that LMWH is unlikely to be a primary cause of hyperkalemia, caution is warranted, especially in patients with elevated baseline potassium levels.

Heparin-induced hyperkalemia in a patient diagnosed with thyroid storm

OBJECTIVE

To describe a case of heparin-induced hyperkalemia and the role for transtubular potassium gradient (TTKG) to guide fludrocortisone therapy.

CASE SUMMARY

A 52-year-old white male developed hyperkalemia after receiving intravenous unfractionated heparin (UFH) for atrial fibrillation during thyroid storm. Admission laboratory results were noteworthy for normal potassium levels, undetectable thyroid-stimulating hormone, and mild transaminitis. Treatment for thyroid storm was initiated but UFH was stopped because the international normalized ratio was subsequently found to be elevated. Rising potassium levels developed just 24 hours after UFH discontinuation, without exogenous potassium supplementation, renal dysfunction, or acidosis. A TTKG was low, reflecting a hypoaldosterone state. In addition, the Naranjo probability scale indicated probable medication-associated hyperkalemia. Heparin-induced hyperkalemia (HIH) was suspected and oral fludrocortisone 0.2 mg was given daily alongside serial TTKG measurements. TTKG and hyperkalemia normalized with 2 days of treatment.

DISCUSSION

UFH is commonly used; therefore, clinicians must be cautious of hyperkalemia. Although HIH usually resolves after discontinuation of heparin, it may persist despite discontinuation of the drug, as highlighted by this case. In this setting, a TTKG should be determined, which can be used to guide fludrocortisone therapy.

CONCLUSIONS

HIH can occur despite discontinuation of heparin, and TTKG can be helpful in guiding fludrocortisone treatment in this circumstance.

Refractory hyperkalemia related to heparin abuse

Hyperkalemia is a potentially life-threatening condition, which may occur in many clinical settings. Heparin-induced hyperkalemia is less well-recognized than other side effects of heparin therapy. Even lesser known is heparin abuse amongst drug addicts. We report a case of fatal hyperkalemia related to long-term heparin abuse, which was refractory to anti-hyperkalemia therapy including hemodialysis. The objective is to alert the clinicians to possible abuse of heparin in drug addicts, which can be a cause for refractory hyperkalemia. We also briefly review the available literature on heparin-induced hyperkalemia.

Effect of heparin and low-molecular weight heparin on serum potassium and sodium levels

Introduction:

To study the effects of heparin and low-molecular weight heparin (LMWH) on potassium and sodium levels in patients with cardiovascular diseases (CVDs) and stroke.

Materials and Methods:

Sixty patients were recruited with 30 patients each receiving heparin and enoxaparin. Patients with CVD and stroke receiving heparin and LMWH were compared for their demographic profile and laboratory data, and this was analyzed by descriptive statistics. Risk factors associated with the development of hyperkalemia were analyzed using multiple logistic regression model.

Results:

There was an increase in potassium levels and decrease in sodium levels compared with baseline in both the groups. The difference between the groups with respect to sodium and potassium levels was not statistically significant. On analysis, the risk factors for development of hyperkalemia were baseline potassium levels, serum creatinine, and creatinine clearance. The change in sodium and potassium levels on the fifth day of therapy was increased with LMWH compared with heparin, although not statistically significant.

Conclusions:

The clinician should anticipate hyperkalemia especially in patients with renal impairment receiving these drugs.