How did Joseph Lister reduce infections during surgery?

Joseph Lister revolutionized surgery by introducing antiseptic techniques to prevent sepsis, which was a leading cause of death in surgical wards at the time. Influenced by Louis Pasteur’s germ theory, Lister recognized that microorganisms were responsible for infection and putrefaction in wounds.12

To combat this, he utilized carbolic acid to create a chemical barrier between the wound and the environment. His antiseptic protocol included:

• Sterilizing surgical instruments.
• Cleaning wounds thoroughly.
• Disinfecting the air and the operating room environment.
• Protecting the surgical site from contamination by the surgeon’s hands.12

These measures were highly effective; in his own ward, surgical mortality rates dropped from 45 percent to 15 percent between 1865 and 1869. Although his specific methods evolved, his fundamental principle—that bacteria must be prevented from entering an operation wound—remains the cornerstone of modern surgical practice.12