IN-VITRO EFFECTS OF SIMULATED GASTRIC-JUICE ON SWALLOWED METAL OBJECTS - IMPLICATIONS FOR PRACTICAL MANAGEMENT

Background: Swallowed metal objects often pose a technical challenge f or the endoscopist. We studied in vitro the effects of simulated gastr ic juice on metal objects commonly encountered in endoscopic practice and measured the physical-chemical changes. Method: Razor blades, disc batteries, and pennies were incubated in simulated gastric juice at 3 7 degrees C. The weights of the objects were recorded hourly. When no change could be detected, the solution was subjected to mass spectrome try to verify absence of effect. The findings were correlated with cli nical observation in one patient who swallowed razor blades repeatedly . Results: Dissolution of the razor blade was proportional to the dura tion of acid immersion. At 24 hours, the blades weighed 63% of the ori ginal weight. Double-edged razor blades could be broken with a snare a t 15 hours. The thickened back of the single-edged blade totally disso lved in 2 hours. No teak of contents could be detected with disk batte ries. Pennies were unaffected. Conclusion: Corrosion of razor blades o ccurs rapidly in the normal stomach. Within 24 hours double-edged blad es become fragile and can be broken with a snare. This observation may guide the timing of endoscopic removal. Modern disk batteries are aci d resistant for 24 hours.