Anytime a patient is required to — or elects to — have surgery, there are always risks involved. Some surgeries, however, carry with them a higher risk due to the difficulty of the procedure, the importance of the organ and the part of the body being operated on. Thanks to the skilled medical professionals who perform these surgeries, along with advanced medical technologies, mortality rates and complications have been significantly reduced. But despite ongoing medical advancements, there are still procedures that present high risk for complications during the procedure or recovery period. Here’s a list of the 10 riskiest medical procedures: 10. Bariatric surgeries/Gastric Bypass As with many other major surgeries, there are risks that patients take when electing to undergo them, but these patients’ excessive weight poses even more threats. Surgeons have a harder time operating and must use special instruments because internal organs are often hard to separate and have may layers of slippery fat surrounding them. These patients also have an increased risk for complications with anesthesia, because it’s often difficult to insert the tube into their airways, and drugs or anesthetic gases may need to be given in higher dosages because they are easily absorbed by fat. Breathing must also be closely monitored before, during and after the surgery, as these patients have a higher risk of developing of pneumonia. 9. Septal Myotomy This surgical procedure is performed to reduce the thickening of the heart muscles, a symptom of patients diagnosed with advanced stages of a complex type of heart disease called hypertrophic cardiomyopathy (HCM). This is a complicated procedure because it requires the patient to be placed on cardiopulminary bypass, or the “heart-lung machine”, so that the surgeon can work on a still heart. In total, this surgery can last anywhere from 3 to 6 hours, and the recovery period requires a stay in the Intensive Care Unit. 8. Pancreatectomy This procedure comes along with a fairly high risk of complications. In fact, a Johns Hopkins study documented complications in 41% of pancreatectomy cases. These include serious problems like post-operative bleeding, delayed gastric emptying — a condition in which food and liquids are slow to leave the stomach — internal anastomatic leaking. The good news is that in recent years, the mortality rate for this procedure has decreased to a range of 5-10%. 7. Thoracic Aortic Dissection Repair Aortic dissection, or a tear in the innermost layer of the heart, can trigger a number of high-risk complications like heart failure, stroke or even a rupture of the aorta, making its repair vital to the survival of the patient. Immediate treatment is required and this often results in the surgeon removing the area of dissected aorta and rebuilding the blood vessel with a synthetic graft. 6. Esophagectomy This is a major surgery which carries a lot of risk because of the reconstruction of the area between the stomach and the healthy part of the esophagus. Three different methods of this surgery can be performed depending on the patient’s condition, but they all carry with them serious risks, such as a leakage of the fluid from the stomach or esophagus where the new connection was made. Despite the risks, most patients recover well and have few complications. 5. Bladder Cystectomy This procedure is most often performed to remove a part of, or the entire urinary bladder, in patients diagnosed with bladder cancer. The major risks for this procedure are the highest for an infection of the intestine which can lead to peritonitis or the inflammation of the membrane lining the abdomen. For procedures that remove only a part of the bladder, there is a high risk for urine leakage from the bladder incision site, which can cause a number of other internal problems.