Nutritional Support in Critical Care

In critical care, a patient receives treatment for a serious illness or injury. The goal of critical care is to eventually discharge the patient into an ambulatory care unit and eventually from the hospital entirely. To improve the effectiveness of the medicine and therapies given to the patient, staff members may provide nutritional support to the patient. Nutritional support in critical care gives the patient's body strength and resiliency for healing and recovery.

Significance

• After experiencing the extreme trauma of an injury or acute illness, the body's metabolism can overextend, resulting in a loss of lean muscle and fat. Such a patient loses muscle and fat because of his body's overproduction of regulatory hormones when responding to the trauma, despite consuming what would otherwise be a healthy diet. Critical care nutrition regulates the body's use of sugar, protein and other fuels to best aid in the patient's recovery.

Types

• Health care professionals deliver nutritional support to patients in one of two ways if the patient is unable to consume adequate nutrition by mouth. One way is enteral feeding, which uses a feeding tube to deliver nutrition to the patient's digestive system. The other is parenteral feeding, which delivers nutrients to the patient intravenously. In general, doctors prefer enteral feeding whenever possible because it is less expensive and is less likely to cause low blood sugar, which can set the patient's recovery back. Doctors use parenteral feeding when enteral feeding is impossible due to digestive system problems or if there is a high likelihood of a patient aspirating the nutrition while on a ventilator.

Benefits

• Doctors prescribe nutrition to their critical care patients that specifically addresses particular recovery needs. For instance, in a multi-center study cited in the Journal of Trauma (October 1994), researchers discovered that trauma patients experienced fewer incidents of multiple-organ failure when fed immune-enhancing nutritional formula. Immune-enhancing nutrition contains various proteins and omega-3 fatty acids to boost the patient's immune system and fight infection and sepsis. Other formulas support healthy respiratory, liver and kidney functions.

Considerations

• Doctors balance the nutrients a patient receives to best enhance the patient's bodily responses to illness. In critical care, many patients experience some time on a ventilator, or breathing machine. When fed a diet high in carbohydrates in relationship to fat, the body produces more carbon dioxide, making the patient on a ventilator work harder to eliminate the carbon dioxide and obtain oxygen. For this reason, a patient on a ventilator in critical care receives nutritional support with a higher fat-to-carbohydrate ratio than might be considered healthy in a person not on a ventilator.

Warning

• Patients receiving enteral feeding can suffer from uncomfortable symptoms such as diarrhea or constipation. Adjusting the type of nutrition the patient receives, the schedule on which she will receive the feedings or, in some cases, adjusting the placement of the tube to feed the person alleviates these symptoms in the majority of patients. Since some patients experience bowel atrophy while on parenteral feeding, causing digestive problems once oral feeding again becomes possible, doctors attempt to keep the patient on enteral feeding unless the patient aspirates large amounts of nutrition or experiences severe gut injury from the enteral feeding. Avoiding bowel atrophy helps patients make a speedier transition from IV or tube feeding back to eating.