CK half life

Q: 44 years old laborer is admitted to ICU with crushing injuries and developing rhabdomyolysis. Proper medical management is initiated. Serial Creatine Kinase (CK) is ordered. What is the half-life of CK? - select one

A) 12 hours

B) 36 hours

C) 48 hours

D) 72 hours

E) 96 hours

Answer: B

Elevated CK is considered as a hallmark for rhаbԁοmуοlуѕiѕ. Other muscle injury markers, such as aldolase, aminotransferases (AST and ALT), and lactate dehydrogenase (LDH), can be followed.

Serum СK above 5000 units/L with non-exertional rhаbԁοmуolуѕiѕ and above 10,000 units/L  with exertional rhаbԁοmуоlуsis should be considered diagnostic.

CΚ has a serum half-life of about 36 hours.

Clinical significance: With proper medical management, CK should decline at a constant rate of 40-50 percent of the previous day's value. If CΚ does not fall as expected, then continued muscle iոjսry, an underlying muscle disease, or compartment syndrome should be considered.

#musculo-skeletal

#laboratory-science

References:

1. Huerta-Alardín AL, Varon J, Marik PE. Bench-to-bedside review: Rhabdomyolysis -- an overview for clinicians. Crit Care 2005; 9:158.

2. Khan FY. Rhabdomyolysis: a review of the literature. Neth J Med 2009; 67:272.

3. Mikkelsen TS, Toft P. Prognostic value, kinetics and effect of CVVHDF on serum of the myoglobin and creatine kinase in critically ill patients with rhabdomyolysis. Acta Anaesthesiol Scand 2005; 49:859.