Validation of Tissue Preservation Using a Vacuum Sealed Formalin-Free Transport System
Richard J Zarbo, Michael Dib, Ruan C Varney, Bruce A Jones, Nelson Main. Henry Ford Health System, Detroit, MI
Background: Formalin fixing and transporting tissue specimens is a process over 100 years old that potentially exposes healthcare workers to toxic, carcinogenic formaldehyde. Formalin spilled in operating room (OR) or laboratory is a health hazard to be contained as a hazardous material. We seek to redesign this work process so formalin is removed from 4 hospitals in the process of transportation of human specimens to an Anatomic Pathology Core Laboratory.
Design: TissueSAFE high vacuum biospecimen transfer system (Milestone Medical, Kalamazoo, MI) was evaluated for vacuum sealed, formalin-free transfer and storage in 3 validations:1) Preservation of surgical specimens vacuum sealed and stored at 4°C and 7°C for 24, 48 and 72 hours compared to paired formalin fixed tissues; 2) Transport and storage of specimens sealed in OR of a community hospital 25 miles away at 4°C for 24 and 48 hours; and 3) Preservation of surgical specimens sealed in FS Room adjacent to 30 ORs then transported at 4°C to the Core Lab within the same hospital, range of storage times 1-10 hours before tissue examination, fixation, processing and histologic assessment. All slides were H+E stained and evaluated by pathologists using a 3 part scale of Acceptable for Diagnosis, Inferior Quality for Diagnosis or Unacceptable for Diagnosis.
Results: SCHEME #1: 9 cases, 7 tissue types (50 blocks): liver, uterus, ovary, lymph node, leg, lung, fatty pannus. All were Acceptable for Diagnosis except for 4 blocks of liver that were under processed and coded as Inferior Quality for Diagnosis. SCHEME #2: 9 cases, 8 tissue types (56 blocks): stomach, gallbladder, placenta, fallopian tube, uterus, thyroid, bowel, fistula. All were Acceptable for Diagnosis by histologic evaluation at 1 and 2 days storage under vacuum in the cold. SCHEME #3: 30 cases, 16 tissue types, (164 blocks): lung, kidney, stomach, uterus, colon, small intestine, gall bladder, thyroid, brain, tonsil, skin, TURBT, TURP, hemorrhoid, appendix, arterial plaque. All but 2 cases were Acceptable for Diagnosis with 1 TURBT (5 hour storage) and 1 kidney (2.5 hour storage) deemed Inferior Quality for Diagnosis due to "air-drying" and lack of crisp cytologic tumor detail, respectively.
Conclusions: Vacuum sealed tissues held at 4°C are preserved for histologic assessment when held in that state up to 48 hours. The nature of the 2 histologically inferior exceptions with low storage times require further study. TissueSAFE vacuum transport shows promise to provide a platform for designing formalin-free ORs and transport of tissue specimens to processing laboratories.
Wednesday, March 6, 2013 9:30 AM
Poster Session V # 279, Wednesday Morning