The Application of a Dried Balanced Heparin Syringe Can Attenuate the Dilution Effect in Rapid Point-of-care Potassium Testing for the Early Identification of Hyperkalemia in the Emergency Department

PURPOSE: Current methods to evaluate the blood concentration of potassium (K) on point-of-care (POC) are influenced by the relative volumes of heparin and arterial blood. Blood potassium concentration may be underestimated with a high volume of heparin or low volume of blood. This dilution effect can produce false negative results that negatively affect decision-making of clinicians and throw critical patients into crisis. We hypothesized that the application of a dried balanced heparin syringe in rapid POC-K+ could attenuate the dilution effect and would more accurately and consistently measure the concentration of potassium compared with reference testing in emergency situations. METHODS: This retrospective study was conducted between January, 1, 2008 and September, 30, 2013 at an urban hospital affiliated with our institution. To attenuate the dilution effect, dried balanced heparin syringes (HS) were also used between October, 1, 2011 and September, 30, 2013. Concentrations of potassium were compared between the dried balanced HS group and the liquid HS group. The reliability of each of these outcome measures was assessed using intra-class correlation coefficient analysis. RESULTS: Application of dried balanced HS improved the degree of concordance for potassium using two different assays. The false negative rate was significantly improved from 9.1% (95% CI 7.3-11.0) to 5.7% (95% CI 3.5-8.0) in the dried balanced HS group compared with the liquid HS liquid group (p=0.037). CONCLUSION: This study suggests that the usage of dried balanced HS could attenuate the dilution effect in rapid POC-K+ and predict potassium levels more accurately for identification of patients at risk of hyperkalemia in emergency situations.

Metastatic Leiomyosarcoma of the Pancreas Mimicking a Cystic Neoplasm: A Case Report

Pancreatic tumors are primary in most cases. Pancreatic metastases associated with other primary malignancies, especially pancreatic metastasis of leiomyosarcoma, are infrequent. A 49-year-old woman underwent surgical resection of a mass in the right groin, which was diagnosed as a leiomyosarcoma and she was well for 4 years without evidence of disease recurrence. As part of her routine follow-up, an abdominal computed tomography (CT) identified a cystic neoplasm of the pancreas. Pylorus-preserving pancreaticoduodenectomy was performed. Microscopically, the tumor was composed of spindle cells with a predominantly fascicular pattern, which was consistent with a leiomyosarcoma that was metastatic to the pancreas. We report here a unique case of pancreatic metastasis from a leiomyosarcoma, which was resectable and mimicked a primary cystic neoplasm.