Whether it’s a routine appointment or a visit with a surgeon, you trust you’re in good hands with medical personnel. Doctors are human too, however — and mistakes do happen. NPR reports on a study that says medical errors should rank as the third leading cause of death. So, what can go wrong when you’re in a doctor’s care? Everything from mixing up medications to unrecognized complications during surgery have occurred in the past. And some of these mistakes have even killed. 1. Operating on the wrong patient The New York Times describes a specific scenario involving two patients with very similar names. The wrong patient was told it was time for her procedure to begin, even though she said she was never told about the surgery. The nurse insisted anyway, and the wrong woman was wheeled back. Eventually, the mix-up was discovered — but it was after the doctors started the invasive procedure. The woman who was wrongfully operated on recovered fully. But it was the negligence, poor communication, and possible fatigue from long work hours that made this scenario possible. 2. Removing a breathing tube too early Peter Provonost, M.D., Ph.D., explains to Reader’s Digest a time when he almost killed a man coming out of esophageal surgery. Provonost thought it was fine to remove the man’s breathing tube and transfer him to another unit. As soon as the tube was removed, the man was losing oxygen fast. It turns out he had severe swelling in his throat, and the tube had to be reinserted. It took Provonost a dangerously long time to reinsert the tube, and the man could have suffered brain damage. Luckily, everything ended OK. Next: Medical personnel can give patients infections if they aren’t careful. 3. Leaving a urinary catheter in for too long It is common for patients to get UTI’s from having catheters in for too long. | iStock.com/monkeybusinessimages The Centers for Disease Control and Prevention explains urinary tract infections are the most common type of infection patients get while receiving hospital treatment. And 75% of the time, these UTIs are caused by urinary catheters staying in too long. It’s important for doctors to remove catheters as soon as they are no longer needed to prevent this painful complication. And while most UTIs can be treated with ease, kidney infections and damage can result if the issue is left untreated. Next: Some doctors think gloves are enough, but that’s not the case. 4. Not washing hands when latex gloves are worn Wearing gloves does not excuse washing hands. | iStock.com/Bojan89 Wearing latex gloves is important — but so is good, old-fashioned hand washing. The New York Times says a study found health care workers who wear gloves in hospitals are less likely to wash their hands before and after seeing patients. Out of the 15 hospitals studied, medical personnel washed their hands just 41% of the time when they were wearing gloves. Perhaps what they don’t realize is that germs can actually travel through latex. This means they’re risking the spread of infection. Next: It’s possible for doctors to give some patients pneumonia. 5. Spreading infection through a ventilator It is possible for patients to come down with pneumonia while in the hospital. | iStock/Getty Images Ventilators are life-saving tools that can help patients with lung problems breathe. It’s not always all good, though. Ventilator-associated pneumonia is more common than you think, and it occurs when germs enter through the tube and reach the lungs. And CBS News also reports those on a ventilator shouldn’t lie down flat, as this can also cause this potentially deadly disease. Dr. Peter Provonost says doctors should prop patients up at least 30 degrees and be checking every day if the ventilator is necessary. Next: This doctor was convicted of involuntary manslaughter for this deadly mistake. 6. Giving the wrong dosage of medication When doctors are careless there can be dire consequences. | iStock.com Wrong dosages happen more often than you think — and in particular incidence, a child was killed. Eric Cropp, president of the Northern Ohio Academy of Pharmacy, made the mistake of not thoroughly checking a saline-solution base that was prepared for a child’s chemotherapy. The pharmacy technician who made the solution accidentally mixed it 20 times stronger than ordered, and Cropp didn’t catch the mistake. It caused the child’s brain to swell, and she died three days later. Cropp was convicted of involuntary manslaughter due to the incident, and he’s still haunted by what happened. Next: This potentially deadly mistake is extremely preventable. 7. Performing surgery on the wrong area of the body You may end up having hip surgery instead of knee surgery. | iStock/Getty Images You may have never considered that a team of surgeons could accidentally operate on the wrong area, but it does indeed happen. The term for this is “wrong-site surgery,” and it exposes patients to additional risk while under operation. Here’s the good news — this doesn’t happen as often as other issues, and there are severe consequences for surgeons who operate wrongfully on a patient. It seems wrong-site surgery is on the rise, however. This mostly occurs in situations where there’s no formal system in place to verify the site of the surgery. In essence, it all comes down to proper communication. Next: We bet you can’t imagine waking up with a surgical tool still inside you. 8. Leaving foreign objects behind in a person’s body Forgetting something inside of a patient can lead to life-threatening infections. | Jacoblund USA Today reports foreign objects are left inside of surgery patients up to a dozen times a day. In one particular instance, a very pregnant Erica Parks was going in for a C-section when a sponge the size of a washcloth was left inside of her abdomen. This resulted in her bowels shutting down completely and a six-hour emergency surgery to remove it. When sponges and other objects are left behind after surgery, life-threatening infections can occur. And usually the doctors can’t figure out the source of the patient’s issue until the case is severe. Next: ER crowding can have severe consequences. 9. Overcrowding in hospital waiting rooms Sometimes patients have to be turned away due to overcrowding. | iStock.com You probably know the feeling of sitting for hours in the ER waiting room. TIME explainsvisits to the emergency room rise every year, and there aren’t enough hospitals, nurses, and doctors to see all patients immediately. This leaves some patients at risk of waiting too long to be seen. And it also presents another issue — diverting ambulances carrying people on the verge of death to less-crowded hospitals that are much further away. This means an ambulance carrying a heart attack victim may have to travel 20 or 30 extra minutes just so that patient can be seen. Next: Not taking a patient seriously can be deadly. 10. Dismissing a patient’s symptoms A patient’s symptoms should never be ignored. | David McNew/Getty Images This happens quite often — and sometimes, it results in death for the patient. Daily Mail Online explains one scenario where a university professor was having a range of strange symptoms. Doctors dismissed her symptoms as psychological, claiming she was just experiencing anxiety and depression. By the time she finally got a diagnosis, doctors discovered she had lung cancer that spread throughout her body. She tried to fight the disease, but died at just 37 years old. Next: In the medical world, too much of a good thing does exist. 11. Over-treating a patient There is a possibility that your doctor is overmedicating you. | iStock.com/monstArrr_ Some doctors are so eager to treat patients that they may be offering them routine procedures and meds that they don’t really need, resulting in more harm than good. The Independent explains evidence suggests doctors are over-diagnosing and over-treating for fear that they may miss something. As cardiologist Dr. Aseem Malhotra tells the publication, there’s now “an overmedicated population with unhealthy lifestyles.” And the potential side effects from these unnecessary meds can carry major risks. Next: These tubes look a lot alike — but when confused, this can lead to death. 12. Mistaking a chest tube for a feeding tube This mistake can prove fatal if not caught immediately. | Mike Simons/Getty Images This might seem odd, but it happens more often than medical personnel would like to admit. As James B. Lieber explains in his book, Killer Care, chest tubes and feeding tubes look incredibly similar. If they’re inserted into the wrong port, however, this can prove fatal. In response to this, Senator Kay Hagan asked how it was possible that ” … we can’t figure out how to make different catheter connections so doctors don’t place patients in harm’s way.” To make sure everything is in the right place, doctors should be tracing every tube inserted into a patient back to its origin. Patients should also be vigilant in asking for this, too. Next: This is what happens when doctors don’t speak up. 13. Not questioning another doctor’s wrong advice Sometimes a nurse should go with their better judgement. | Christopher Furlong/Getty Images Nurse Sunnie Bell explains a scenario she found herself in while on an evening shift. An 85-year-old patient was in increasing pain, and it was thought that she may have a bowel obstruction. Bell called a doctor about the woman’s worsening condition — but he said her surgery should wait until the next morning. Despite Bell’s better judgment, she followed the doctor’s orders — and the patient died the following morning. It seems like Bell should have spoken up against the doctor, but a lack of protection and support for nurses can make this difficult. For this reason, examples like this may happen quite often. Next: This type of error could happen right in your pharmacy. 14. Prescribing the wrong type of medication altogether Your doctor could actually prescribe the wrong medication altogether. | BCFC/iStock/Getty Images U.S. News & World Report says anywhere from 1% to 5% of prescriptions have some kind of error when they’re filled. And because many drugs have similar names or look alike, it can be easy for the pharmacist to grab the wrong one. One infamous mix-up occurred between the generic brand for Ritalin, which is methylphenidate, and the narcotic given to treat heroin addicts, methadone. Accidental switches such as this can result in death. Next: This fatal issue can cause a heart attack or a stroke. 15. Causing air bubbles to enter a patient’s blood If an air bubble travels to your brain it can be fatal. | iStock.com/Airubon When air bubbles enter a vein or an artery, they can block blood flow — and the bubbles can also travel to the brain, heart, or lungs, causing death. This seems bizarre, but Healthline explains this can happen during a syringe or IV injection while you’re at the hospital. It’s also quite common to have an air embolism during surgical procedures, like brain surgery. The majority of the time, doctors find and correct the issue — but if it goes undetected, this can result in death. Source