[Interest of a systematic second-look at 48-72 hours in high-pressure injections of paint: an animal study]

Abstract

Study purpose: High-pressure injections (HPI) in the hand are rare and their prognosis is often tragic, some authors report up to 48% of amputations. Poorly standardized, their management is often too late and inadequate. The HPI of paint results in inoculation of toxic particles in depth that are particularly difficult to remove surgically. The persistence of this foreign material maintains local inflammation and increases the risk of infection. We wanted to simulate in rats, the physiopathology of HPI with paint. The aim of this study is to authenticate an advantage to achieve consistently a second surgical debridement at 48-72 hours in HPI with paint.

Materials and methods: Six rats were injected with 200 bars of white glycerophtalic paint in the leg. At six hours and then every 24 hours for four days, we did a debridement and a surgical washing, then at the end of intervention a tissue sample was analyzed by histology.

Results: Despite surgical debridement and thorough washing, at each step we found the persistence of painting in the intermuscular septa by light microscopy. From 24 hours, a necroinflammatory process is set up with an influx of neutrophils, organizing themselves into micro-abscesses. It will be very deleterious, initially by encouraging risk of sepsis, and then facilitating the formation of extensive fibrosis, which is the cause of functional impairment.

Conclusion: We established the kinetics of tissue under HPI with paint using an animal model. It appears that single emergency surgery is insufficient to manage this "septic compartment syndrome". Therefore, we recommend a systematic surgical "second look" at 48-72 hours to complete the debridement of residual inoculum and necrotic tissue without wound closure.