Nutrition support experts want you to think of food as a drug. Not in the negative sense of addiction, but positively as a therapy that's critical to helping hospitalized patients get better.
In current practice, nutrition support is provided with significantly less diligence and precision than medication. “Study after study after study has shown that patients get about 50% of [the nutrition] they should get when they're on enteral feeding,” said Stephen A. McClave, ACP Member, professor of medicine in gastroenterology at the University of Louisville.
Compare that to the provision of antibiotics for an infectious disease. “If you came back after 14 days and [patients] only got 40% to 50% of the antibiotic that was prescribed, think of the reaction that people would have to that level of performance. We're trying to say, ‘That's a quality issue,’” explained Daren Heyland, MD, associate professor of medicine at Queen's University in Kingston, Ontario.
Advocates of nutritional support recently garnered attention for their concerns in new guidelines from the American Society for Parenteral and Enteral Nutrition (ASPEN) and the Society of Critical Care Medicine. “Guidelines for the Provision and Assessment of Nutrition Support Therapy in the Adult Critically Ill Patient” were published in the May Journal of Enteral and Parenteral Nutrition.
“We really made an effort to fill in the gaps, to tell how soon to start, how fast to ramp up, what things to watch for,” said Dr. McClave, who is also the president of ASPEN. “It also shows some of the controversial areas involved in pharmaconutrition.”
More is more
One area where there's no controversy, at least among the experts, is on the need to provide greater nutrition support. In interviews, experts were united in their call for more and earlier attention to the nutritional needs of hospitalized patients.
“There's a lot of literature that clearly demonstrates that a [cumulative] caloric deficit of as little as 10,000 calories can increase the morbidity of a patient in the intensive care unit. Most deficits build up in the first week or so of admission,” said Lillian Harvey-Banchik, MD, a surgeon and nutrition expert from North Shore University Hospital in Manhasset, N.Y. (See Mault J, J Parenter Enteral Nutr. 2000.)
Such deficits aren't intentional, she added. “It's just never at the top of the list of things [physicians] have to think about with the patient and that's when they get into trouble.” Diagnostic tests, concerns about ileus, and surgical procedures, among other factors, often take precedence over the provision of nutrition.
“They keep thinking the patient's going to eat more tomorrow. Before you know it, two weeks have gone by,” noted Alan L. Buchman, FACP, a professor of medicine and surgery at the Feinberg School of Medicine, Northwestern University.
Or to be more exact, usually about five days go by. Dr. McClave and colleagues studied three months of admissions at the University of Louisville Hospital and found that almost 22% of patients remained NPO for three days or more, with an average of 5.2 days and a range up to 16 days. The findings were replicated almost exactly in a study at the University of Pittsburgh Medical Center Shadyside.
That's too long, and when nutrition support is finally prescribed, it's usually too little, said Dr. McClave. “Day in and day out, doctors order about 65% of what they should be ordering.”
One major stumbling block is that physicians fear patient intolerance of enteral feeding. “They have many, many roadblocks in their mind,” said Mark H. DeLegge, MD, director of nutrition at the Medical University of South Carolina. “Will they vomit? Will they develop diarrhea? Will they regurgitate and aspirate?”
To help solve the problem, physicians could increase their use of strategies that have been proven to reduce intolerance. Dr. Heyland has surveyed hospitals and found that techniques such as motility agents and small bowel feeding tubes are underused. “We know from our audits that in the case of motility agents, only 60% of the time are they being used in these patients,” he said.
Do it fast
Ironically, the longer one waits to start enteral feeding, the more likely intolerance is. “One of our key recommendations is to start enteral feeding early. In U.S. hospitals, that doesn't happen. Your patient is already behind the eight ball and their gut is less likely to respond or tolerate nutrition,” said Dr. Heyland.
Speed is even more crucial in very ill patients. “The sicker you are, the more important it is to feed the gut and timing becomes more important. If they're critically ill, for example, you want to get feeds going in the first 24 hours,” said Dr. McClave.
Enteral feeds, that is. When to start parenteral feeding is one of the controversial issues in nutrition support. The ASPEN guidelines call for waiting a week before instituting parenteral feeds for previously healthy patients who can't take nutrition enterally.
“That's probably a bad choice. One cannot be definitive, one can only read the data in different ways,” said Bruce Bistrian, MD, chief of clinical nutrition at Beth Israel Deaconess Medical Center and professor of medicine at Harvard Medical School.
The recommendation should certainly be taken with a “grain of salt,” according to Dr. DeLegge.
The data in question address the rate of complications from parenteral nutrition. Dr. DeLegge is one of those who think that the risks are underappreciated by physicians. “We've learned over time in many, many different studies, when we've looked at people placed on parenteral nutrition, there seems to be a higher incidence of infections and sepsis,” he said.
However, if proper precautions are taken, the infections are not a necessary consequence of parenteral nutrition, other experts argued. “Ninety percent of the infections that relate to TPN [total parenteral nutrition] are related to the operator, not the patient,” said Dr. Buchman.
Good catheter care—effective sterilization, using the nutrition catheter for only that purpose—can dramatically reduce the risks. “Many, many large hospitals have been successful at using a variety of algorithms to get the catheter infection down to a very, very low level,” said Dr. Bistrian.
Some clinicians' reluctance to use parenteral nutrition is a result of early mistakes made with the technique, Dr. Harvey-Banchik said. “There's an attitude that comes from the early days of parenteral nutrition when we didn't realize that overfeeding the patient had its own inherent risk. People still say parenteral is poisonous.”
It's also difficult to change your view of a therapy once you've seen the potential downsides firsthand, Dr. Buchman noted. “Doctors learn from their experience, sometimes more so than from actual data. When they have a bad experience, sometimes they're reluctant to put themselves in a situation [again].”
Is Europe right?
At least one expert thinks that U.S. physicians are striking the right balance with parenteral nutrition. “We use it in small numbers of patients—10% of patients—and we use it late. [We've] probably been waiting for their gut to get better and trying enteral feeds. A week has passed and it's not working so we try parenteral nutrition. I don't have a problem with that,” said Dr. Heyland.
Dr. Heyland has studied the use of nutrition support therapies around the world, and found higher use of parenteral nutrition in Europe compared to the U.S. Europeans are also more likely to use parenteral nutrition as a supplement to enteral nutrition, a technique that's still under debate in this country.
The rationale behind supplemental parenteral nutrition is clear. All the experts agreed that a large percentage of patients on enteral feeds get insufficient nutrition. Even beyond the reluctance to start and underprescribing, enteral nutrition goals are difficult to meet in the hospital.
“The tube feeding is stopped for virtually anything. The patient goes to X-ray and they stop the tube feeding. The patient gets examined and they stop the tube feeding. The patient goes to get anesthesia…Although the intentions are good, it's either never advanced beyond the slow feeding rates or it's discontinued so often that it is inadequate,” said Dr. Bistrian.
Parenteral feeding, on the other hand, does not have to be halted so often. For example, when a patient's getting a tracheotomy, enteral feeding might be stopped the night before, even though the surgery's not until late afternoon the next day, said Dr. Harvey-Banchik. “You've now gone 16 to 18 hours without the person being fed. With parenteral, you often don't have that issue. It's only stopped for two or three hours.”
She favors the use of both nutritional methods together, and will give a little enteral nutrition (10 to 20 cc per hour) to patients receiving parenteral. The practice has multiple benefits, according to Dr. Harvey-Banchik. “One, you keep the GI tract in some kind of shape. And two, it gives a handle on whether the patient can tolerate it.”
The combination strategy is the subject of several studies currently under way, although the research focuses more on the opposite situation—adding parenteral nutrition for patients already on enteral feeding.
“The Europeans, that's their style. If you aren't feeding 80% of goal calories after 24 hours with the enteral route, they add in the supplemental TPN,” said Dr. McClave.
Currently, he—like the guidelines—favors waiting a week as long as the patient was not malnourished prior to hospitalization. But any contradictory data from three ongoing large studies comparing enteral nutrition supplemented with parenteral versus enteral alone (underway in Canada, the Netherlands and Switzerland) could affect his stance. “If any of those studies are positive in favor of supplemental PN, that will change the way we practice.”
There's also ongoing research about the addition of immune-modulating agents (such as arginine, glutamine and antioxidants) to nutrition formulas. Probiotics initially showed promise for improving outcomes in the ICU, until a recent study in pancreatitis showed the possibility of harm. “It's funny how things are hot and cold. Right now we're backing off probiotics in the critically ill,” Dr. McClave said.
Hospitalists and their team
It's a lot for a hospitalist to keep track of, which is why nutrition support should really be a team effort, the experts said.
“The greatest ally for knowing how adequately someone is eating is the clinical dietitian,” said Dr. Bistrian. “She's probably the most knowledgeable person about enteral feeding in the hospital, more so than most doctors.” Dietitians can assess nutritional status and needs and help develop a treatment plan.
Hospitalists do need to be involved with nutrition from the start, however, Dr. Buchman said. “Every patient who comes into the hospital should have some basic nutritional assessment by the physician, not just the dietitian. Often there's not good communication between the dietitian and the physician.”
In hospitals with nutrition support services, decisions about nutrition therapy and its execution can be passed off to experts. But in facilities without those services, a lack of personal expertise should not determine what type of therapy a patient receives, Dr. Bistrian said.
“If a hospitalist needs to go to parenteral nutrition, he shouldn't avoid it because he doesn't know how to do it. He should get someone with the proper expertise. The pharmacist will make the formula, the nurses will care for the catheter, the dietitian will do calorie counts and usually a surgeon or a vascular access person will place the catheter for him.”
There is one more person who should get a say in the process—the patient. Studies of patient preference have found, not surprisingly, that the majority opt for an intravenous line. “Most people will say, ‘I don't really want a tube in my nose,’” said Dr. DeLegge. “If you had your druthers, sure, no one wants a tube in their nose or in their belly. But if you talk about the risk of infection and the risk of complication with parenteral, that may cease to be a problem for the patient.”
In some cases, however, it's best just to give in to the wishes of the patient or family, according to Dr. Harvey-Banchik. “To do things to the patient that look very uncomfortable sometimes upsets the family. You say, ‘OK, let's feed [the patient] this way. As soon as they can swallow, let's start feeding.’”
Whatever the method—food on a plate, enteral, parenteral—the nutrition support experts just want hospitalists to make sure everyone's getting fed. “Keep every day saying, ‘Can I feed this person? What am I missing as far as feeding this person?’ Start early and think about it every day,” said Dr. Harvey-Banchik.
And once hospitalists are thinking about nutrition, the hope is that the rest of the medical world will follow. “[Hospitalists] have a really, really good mentor program. This is a group that's capable of really upgrading practice. ASPEN and the nutrition society are very excited about hospitalists,” said Dr. McClave. “If these guys get turned on to nutrition, then everybody's going to win.”