Evaluation of the performance and clinical impact of a rapid intraoperative parathyroid hormone assay in conjunction with preoperative imaging and concise parathyroidectomy

Background: Tc-99m-sestamibi scans and rapid, intraoperative intact parathy roid hormone (PTH) assays allow preoperative identification of diseased gla nds and intraoperative confirmation of diseased gland removal, respectively . Use of these two new technologies may facilitate simpler, more concise su rgery, shorter hospital stays, and decreased costs for frozen-section analy sis. One major drawback to this new strategy has been the high cost of rapi d point-of-care PTH assays. Methods: We performed rapid PTH assays with the DPC Turbo PTH assay on the DPC IMMULITE automated analyzer. The number of intraoperative frozen sectio ns, type of anesthesia, surgical approach, length of hospital stay, and pre - and postoperative calcium values were compared between a group of 49 pati ents undergoing parathyroidectomy where the intraoperative PTH assay was us ed in conjunction with preoperative imaging, and a historical control group of 55 patients before the use of these two technologies in our institution . Results: Comparison of the Turbo PTH assay to the standard IMMULITE PTH ass ay gave the following: y = 1.08x - 4.36 (I = 0.97; n = 48). For the 49 pati ents, the median turnaround time for each intraoperative PTH determination was 19 min (range, 14-40 min). The median decrease in PTH values from basel ine was 88% (range, 33-99%). Thirty-seven patients required two PTH determi nations, 7 required three, 4 had four, and 1 required five determinations. The average laboratory cost for the rapid intraoperative PTH assays was < $ 100 per patient (range, $55 to $113). Compared with the control group, the experimental group had significantly fewer frozen sections (1.4 vs 2.5; P < 0.0001), shorter hospital stays (17 discharged on the day of surgery vs non e discharged on the day of surgery; P <0.0001), greater use of local anesth esia (33% vs 0%; P <less than>0.001), and more unilateral, rather than bila teral neck explorations (65% vs 0%; P <0.001). Conclusions: The combination of intraoperative Turbo PTH assay and preopera tive Tc-99m-sestamibi scans can lead to significant decreases in laboratory and surgical pathology costs, hospital stays, and exposure to general anes thesia by facilitating concise parathyroidectomy surgery. (C) 2001 American Association for Clinical Chemistry.