Right combination can prevent clogged tubes

Administering meds a major problem

Synopsis: Obstruction of enteral feeding catheters occurs frequently and is a major practical concern. Factors associated with lower rates of obstruction are a collaboration between nursing and pharmacy and attendance at an inservice education seminar.

Source: Belknap DC, et al. Am J Crit Care 1997; 6(5): 382-392.

Enteral feeding catheters (EFCs) allow earlier and more complete nutritional replacement for seriously ill patients who cannot swallow or are at risk for aspiration. With a functioning EFC, the enteral route is available for administration of medications, which has many advantages including a wider selection of oral preparations, lower cost, and avoidance of the risks associated with intravenous catheters. Concurrent administration of enteral feedings and medications, however, may cause obstruction of the tube.

Although obstructed tubes are usually irrigated successfully, additional nursing time is required and feeding or medication administration may be delayed. If the obstruction cannot be cleared, the catheter must be replaced, increasing cost, patient discomfort, possible mucosal trauma, and exposure to radiation or additional surgical intervention to replace a clogged jejunostomy or percutaneous endoscopic gastrostomy tube.

Because ICU nurses have primary responsibility for management of enteral feeding catheters and administration of medications, their knowledge and technique directly affect patient outcomes.

In this study, a survey design was chosen to determine the prevalence of EFC obstruction in the ICU and to evaluate knowledge and practice related to management of EFCs and administration of medications among critical care nurses. A 52-item questionnaire was designed, based on literature review and clinical experience, to evaluate application of these recommended practices:

· Flush catheter before and after administering medication.

· Do not crush enteric-coated or sustained-release formulations.

· Dilute liquid medications before administration.

· Do not add medications to enteral feeding formula.

· Administer each medication separately.

· Flush with water between medications.

· Consult pharmacist about availability of liquid dosage form, alternative dosage equivalents, and drug-nutrient compatabilities.

Invitations were sent to a random sample of the 12,000 members of the American Association of Critical Care Nurses. Questionnaires were sent to the 1,700 respondents who were interested in participating and actively engaged in nursing practice, 68.6% of whom returned the questionnaires. Survey participants reported an average 13.6 years of nursing experience, and almost half (49.7%) had baccalaureate degrees. Respondents estimated that 34% of their patients had EFCs in place and on average received a total of nine doses of six different medications each day. They estimated that half of all EFC obstructions occurred because of the administration of medications through the EFC. The number of EFCs becoming obstructed due to medications was estimated to be 16% of the total.

A cluster of practices emerged as strong indicators for avoiding EFC obstruction: Nurses that consulted with a pharmacist to obtain liquid forms of medication, had attended an inservice education seminar, and did not crush enteric-coated medications gave significantly fewer medications that required crushing and gave more liquid forms. They reported significantly fewer obstructions due to medications and a lower overall rate of EFC obstruction.

Almost 60% of the nurses thought that pharmacists knew about the proper procedures and directed questions to them, and more than 80% of the nurses consulted other nurses for information. Although the majority reported using one to three inappropriate techniques, this did not correlate with EFC obstruction. The greatest correlation with obstruction was not obtaining available liquid forms of medication and routinely crushing enteric-coated or sustained-release medications. Surprisingly, there was no correlation between caliber of the tube and frequency of obstruction.

Comment by Doreen M. Anardi, RN, critical care research coordinator, department of surgery, Harborview Medical Center, Seattle.

Even the seemingly simple practice of giving medicine and food through a tube into the gastrointestinal tract is fraught with potential problems, which proves that hardly anything is really simple these days. More sophisticated selections of feeding formulas that can be tailored to each patient's nutritional needs lead to unanswered questions about compatabilities with medications. The ability to use the enteral route for medications in the ICU requires a broadened knowledge base about medication administration in this previously parenteral setting.

Clearly, medications need to be given so that they can create their desired effect and not be inactivated or contribute to adverse effects because of drug-drug or drug-formula incompatibilities. Many EFC obstructions can be avoided by using research-based recommended practices. However, some other elements or conditions may be contributing to obstructions.

Belknap and colleagues have combined a helpful review of the available literature regarding medication administration through EFCs, with results of a knowledge/practice survey that points us toward unanswered research questions and the need for educational programs directed at improving practice in this area.