For pancreatic cancer patients, an operation known as the Whipple procedure can add years to their lives. But the surgery lasts several hours and comes at the risk of blood clots, pneumonia, and infections. The mortality rate for the operation is around five percent.

But doctors in Philadelphia have devised a small tweak they say reduces complications and could save lives — they made the saline drip a little saltier. "This relatively minor change in intravenous fluids has had a tremendous effect on the overall complication rate for our patients," said Harish Lavu, who led a new study out of Thomas Jefferson University, published Tuesday in the journal Annals of Surgery, according to a press release. "Based on these findings we have already changed our practice in the operating room to use hypertonic saline."

During surgery, the intravenous drip of hypertonic saline is like the motor oil in your car, keeping all the parts running smoothly. It maintains patients' blood pressure, keeps them hydrated, prevents swelling, and clears out fluids that build up in the lungs and between the cells. Researchers are often tinkering with the types of IV fluids they use during various surgeries in hopes of finding the optimal mixture. In a recent extreme example, doctors in Pittsburgh have even begun swapping patients' blood for cold saltwater to keep them alive longer during emergency surgery.

In this case, the change was much more subtle. By raising the levels of salt and lowering the total volume of fluid, the researchers found the rate of Whipple surgery complications decreased by 25 percent. (To find out, they compared the complication rate between a control group of 128 patients and a test group of 131 patients.)

The researchers say the increased levels of salt proved more effective at clearing fluid buildup. Too much of that fluid can lead to swelling, which is the main culprit in blocking the flow of blood and oxygen that speeds up the healing process. "We are confident that this change in our surgical process will help our patients recover faster with fewer complications," co-author Charles J. Yeo said in the release.

Source: Lavu H et al. The HYSLAR trial: A prospective randomized controlled trial of the use of a restrictive fluid regimen with 3% hypertonic saline (HYS) versus lactated ringers (LAR) in patients undergoing pancreaticoduodenectomy. Annals of Surgery. 2014.