Somewhere between 4,000 and 6,000 times per year in the United States, surgeons close incisions with sponges, instruments, or other objects still inside patients. That works out to roughly one retained surgical item for every 5,500 operations—rare in percentage terms, but staggeringly common in absolute numbers.
These are called "never events," a term that captures both the aspiration and the failure. They should never happen. Yet they keep happening.
What Gets Left Behind
Surgical sponges top the list. They're used by the dozen to absorb blood during surgery—soft, absorbent squares that become saturated and indistinguishable from tissue when soaked with blood. A complex abdominal surgery might use fifty or more sponges over several hours. In that environment, losing track of one isn't hard to imagine, even if it's never acceptable.
But sponges aren't the only problem. Clamps and forceps get left behind. Retractor blades. Scalpel tips that break off. Suture needles. Guidewires used in catheter placement. If it enters the surgical field, it can be left there when the surgeon closes.
Why Counting Fails
The protocol seems foolproof: count every item before surgery begins, count again before closing. If the numbers don't match, find what's missing before the patient leaves the operating room. This system has been standard practice for decades, and it fails regularly.
It fails because humans make errors under pressure. Long surgeries stretch over many hours, during which staff may rotate and counts may transfer imperfectly between shifts. Emergency cases happen without time for meticulous pre-operative counting. Unexpected complications demand immediate attention, distracting everyone from the sponge count that was supposed to happen. Sponges saturated with blood look like blood clots, like tissue, like anything but the foreign object that needs to come out.
Counts can even be "correct" and still wrong. Count the same sponge twice, miscounting another pile, and the numbers balance while a sponge remains inside the patient. The protocol provides an illusion of safety that can mask the very errors it's designed to prevent.
What Happens Next
Some patients are fortunate, in a grim sense—the retained object causes no symptoms and is only discovered incidentally on imaging years later, a curiosity rather than a crisis. Most aren't so lucky.
Pain is usually the first sign. Persistent, unexplained pain at or near the surgical site that doesn't improve with normal healing. Often it gets dismissed initially as routine post-operative discomfort. Take some ibuprofen. Give it time. Meanwhile, the foreign object is causing damage that compounds with each passing day.
Infection follows as the body reacts to material that doesn't belong there. Abscesses form around retained sponges. Bacteria flourish in tissue that can't heal properly. What started as localized infection can progress to sepsis—a life-threatening systemic response that kills patients in hospitals every day.
Obstruction occurs when retained objects block normal organ function. A sponge in the abdomen can cause bowel obstruction, preventing normal digestion and requiring emergency surgery. Rigid instruments can erode through tissue walls, puncturing organs and blood vessels, causing internal bleeding or peritonitis.
Nearly every case requires additional surgery to retrieve the retained object. That means another operation with all the attendant risks—anesthesia, infection, complications—plus extended recovery time and the psychological burden of knowing someone left something inside you.
Why These Cases Are Strong
Retained surgical items are what lawyers call res ipsa loquitur cases: "the thing speaks for itself." You don't need expert testimony to establish that leaving a sponge inside a patient falls below the standard of care. The fact that it happened is the proof of negligence. No competent surgical team intends to leave objects inside patients, so the presence of that object demonstrates that something went wrong with the processes designed to prevent exactly this outcome.
This shifts the dynamics of the case significantly. The hospital and surgical team can't credibly argue that they did nothing wrong—the evidence of error is right there in the imaging study or the pathology report. The questions become about damages: how badly was the patient hurt, what additional treatment was required, what compensation is appropriate for the pain, the risk, the additional recovery time, and the violation of trust that comes from knowing the people you trusted with your body left something inside it.