Antibiotics: the hidden allies behind surgery

What comes to mind when you think of surgery?

Perhaps it is the surgeons’ steady hands, the anaesthetist’s expertise, the bright lights of the operating theatre, advanced medical equipment, and a trained healthcare team. All of these are essential.

However, behind many successful operations is an invisible ally that rarely receives the attention it deserves: antibiotics.

Antibiotics are medicines used to treat infections caused by bacteria, such as pneumonia, urinary tract infections, or skin infections. However, these precious medicines also play a fundamental role in making surgery safe.

Every surgical procedure, from joint replacements and bowel surgery to organ transplantations and emergency operations, temporarily bypasses the skin, one of the body’s most effective natural defences.

Although operating rooms are designed to minimise contamination and surgical teams follow rigorous infection prevention protocols, it is impossible to eliminate bacteria completely.

Microorganisms live naturally on our skin, inside our intestines and in the surrounding environment. When the skin is opened during surgery, these bacteria can enter tissues that are normally sterile, increasing the risk of infection.

To reduce the risk of infection, antibiotics may be given shortly before certain operations. This is known as surgical antibiotic prophylaxis.

Importantly, prophylactic antibiotics are not required for every surgical procedure. The decision depends on the type of operation, the risk of infection, the potential consequences of an infection, and patient’s individual risk factors.

Surgical antibiotic prophylaxis is generally recommended when the risk of infection is sufficiently high, such as in clean-contaminated or contaminated procedures. It may also be recommended for some clean operations when an infection could have particularly serious consequences, for example when a prosthetic joint, implant or other foreign material is being inserted.

And there is an important distinction: when a patient already has an infection, antibiotics are being used to treat an infection, not as surgical prophylaxis.

When prophylactic antibiotics are indicated, they need to remain effective against the bacteria most likely to cause infection. This is where antimicrobial resistance (AMR) becomes particularly important.

Every unnecessary antibiotic exposure creates an opportunity for resistant bacteria to emerge or spread. Surgical prophylaxis therefore needs to be used wisely: the right antibiotic, for the right operation, at the right time, and for no longer than necessary.

Using antibiotics when they are not indicated does not make surgery safer. Instead, it can expose patients to unnecessary adverse effects and contribute to AMR.

For surgery, this represents a serious threat: procedures that are currently safe could become increasingly dangerous if infections become more difficult or impossible to treat.

The impact of AMR is especially concerning for patients who are more vulnerable to infections, including those undergoing cancer treatment or organ transplantation, or those having complex surgical procedures. For these people, effective antibiotics are life-saving medicines.

Most of us will never see the antibiotic that protects us during an operation. It is often given through an intravenous line shortly before the operation begins, and it remains invisible, quietly working in the background.

When prophylactic antibiotics are indicated, they can play an important role in making surgery safer. But protecting this benefit means using these medicines only when they are needed, and using them correctly.

The next time you think about surgery, remember antibiotics, the hidden allies that make so much of it possible. Talk to your doctor about surgical prophylaxis