Blast injuries from glass bottles containing dry ice

Mechanism and prognostic indicators for explosion-related eye trauma: eye injury vitrectomy study

PURPOSE

To explore the clinical features, surgical interventions and prognosis of injured eyes following explosion and to develop the risk factors for poor prognosis.

METHODS

A nested case-control study. To the date of 31 December 2018, 99 explosion-related eye globes were selected from the Eye Injury Vitrectomy Study database, which is a multicenter prospective cohort study and began in 1990s. All cases selected underwent vitreoretinal surgery or enucleation and were followed up for at least 6 months. Clinically meaningful preoperative variables and outcomes were used to develop logistic regression models.

RESULTS

The unfavourable outcomes were defined as silicone oil-filled eyes, phthisis bulbi, enucleation and anatomically restored eyes whose final BCVA is worse than initial vision after 6 months of follow-up. The proportion of unfavourable outcomes was 92.0%, 60.9% and 66.7% in large festive fireworks, detonator and beer bottle groups respective. The anatomic and visual outcome of injured eyes with combined injury of blast wave and projectile were worse than that of ruptured eyes (Fisher's exact = 0.041). The extrusion of iris/lens (OR = 3.20, p = 0.015), PVR-C (OR = 6.08, p = 0.036) and choroid damage (OR = 5.84, p = 0.025) is independent risk factors of unfavourable prognosis for explosion-related eye trauma.

CONCLUSION

The extrusion of iris/lens, PVR-C and choroid damage is the independent risk factors for unfavourable outcomes in explosion-related eye trauma. There is a unique injury mechanism in explosion-related eye trauma.

SUMMARY STATEMENT

Through the nested case-control study, the extrusion of iris/lens, PVR-C, and choroid damage are the independent risk factors for unfavorable outcomes in explosion-related eye trauma. The mechanism of open globe mixture and close globe mixture in explosion-related eye trauma need more cases and participating units to explore together in the future.

Carbon dioxide poisoning

Carbon dioxide is a physiologically important gas, produced by the body as a result of cellular metabolism. It is widely used in the food industry in the carbonation of beverages, in fire extinguishers as an 'inerting' agent and in the chemical industry. Its main mode of action is as an asphyxiant, although it also exerts toxic effects at cellular level. At low concentrations, gaseous carbon dioxide appears to have little toxicological effect. At higher concentrations it leads to an increased respiratory rate, tachycardia, cardiac arrhythmias and impaired consciousness. Concentrations >10% may cause convulsions, coma and death. Solid carbon dioxide may cause burns following direct contact. If it is warmed rapidly, large amounts of carbon dioxide are generated, which can be dangerous, particularly within confined areas. The management of carbon dioxide poisoning requires the immediate removal of the casualty from the toxic environment, the administration of oxygen and appropriate supportive care. In severe cases, assisted ventilation may be required. Dry ice burns are treated similarly to other cryogenic burns, requiring thawing of the tissue and suitable analgesia. Healing may be delayed and surgical intervention may be required in severe cases.