Veterinary Teaching Hospital, Atlantic Veterinary College, University of Prince Edward Island, Charlottetown, PE, Canada.
Department of Companion Animals, Atlantic Veterinary College, University of Prince Edward Island, Charlottetown, PE, Canada.
J Am Vet Med Assoc. 2021 Dec 9;260(2):187-193. doi: 10.2460/javma.20.09.0530.
To compare potassium concentrations in feline plasma and serum samples analyzed promptly after collection or after 20 to 28 hours of refrigerated storage.
41 cats.
A venous blood sample was obtained from each cat. Aliquots were placed in 2 tubes without anticoagulant (blood was allowed to clot to derive serum) and 2 tubes with heparin (to derive plasma). One serum and 1 plasma sample were kept at room temperature and analyzed within 60 minutes after collection (baseline); the other serum and plasma samples were analyzed after 20 to 28 hours of refrigerated storage. At both time points, serum and plasma potassium concentrations were measured.
Median baseline serum potassium concentration (4.3 mmol/L) was significantly higher than median baseline plasma potassium concentration (4.1 mmol/L). The median difference between those values was 0.4 mmol/L (95% CI, 0.2 to 0.5 mmol/L). Compared with their respective baseline measurements, the median serum plasma concentration (4.8 mmol/L) and median plasma potassium concentration (4.6 mmol/L) were higher after 20 to 28 hours of refrigeration.
Results indicated that with regard to potassium concentration in feline blood samples, clotting or refrigerated storage for 20 to 28 hours results in a significant artifactual increase. Detection of an unexpectedly high potassium concentration in a cat may represent pseudohyperkalemia, especially if the blood sample was placed in a no-additive tube, was stored for 20 to 28 hours prior to analysis, or both.
比较采集后立即或冷藏保存 20 至 28 小时后分析的猫血浆和血清样本中的钾浓度。
41 只猫。
从每只猫采集一份静脉血。将等分试样放入 2 个无抗凝剂的管（让血液凝固以获得血清）和 2 个含肝素的管（以获得血浆）中。一份血清和 1 份血浆样本在室温下保存，并在采集后 60 分钟内（基线）进行分析；另一份血清和血浆样本在冷藏保存 20 至 28 小时后进行分析。在这两个时间点测量血清和血浆钾浓度。
基线时血清钾浓度的中位数（4.3 mmol/L）显著高于基线时血浆钾浓度的中位数（4.1 mmol/L）。两者之间的差值中位数为 0.4 mmol/L（95%CI，0.2 至 0.5 mmol/L）。与各自的基线测量值相比，冷藏 20 至 28 小时后，血清血浆浓度的中位数（4.8 mmol/L）和血浆钾浓度的中位数（4.6 mmol/L）更高。
结果表明，就猫血液样本中的钾浓度而言，凝血或冷藏保存 20 至 28 小时会导致明显的人为增加。在猫中检测到异常高的钾浓度可能代表假性高钾血症，特别是如果血液样本置于无添加剂管中，在分析前保存 20 至 28 小时，或者两者兼而有之。
