What Is Known About Methods of Correctly Placing Gastric Tubes in Adults and Children

Nursing administration of medication via enteral tubes in adults: a systematic review

BACKGROUND

Enteral tubes are frequently inserted as part of medical treatment in a wide range of patient situations. Patients with an enteral tube are cared for by nurses in a variety of settings, including general and specialised acute care areas, aged care facilities and at home. Regardless of the setting, nurses have the primary responsibility for administering medication through enteral tubes. Medication administration via an enteral tube is a reasonably common nursing intervention that entails a number of skills, including preparing the medication, verifying the tube position, flushing the tube and assessing for potential complications. If medications are not given effectively through an enteral tube, harmful consequences may result leading to increased morbidity, for example, tube occlusion, diarrhoea and aspiration pneumonia. There are resultant costs for the health-care system related to possible increased length of stay and increased use of equipment. Presently what is considered to be best practice to give medications through enteral tubes is unknown.

OBJECTIVES

The objective of this systematic review was to determine the best available evidence on which nursing interventions are effective in minimising the complications associated with the administration of medications via enteral tubes in adults. Nursing interventions and considerations related to medication administration included form of medication, verifying tube placement before administration, methods used to give medication, methods used to flush tubes, maintenance of tube patency and specific practices to prevent possible complications related to the administration of enteral medications.

SEARCH STRATEGY

The following databases were searched for literature reported in English only: CINAHL, MEDLINE, The Cochrane Library, Current Contents/All Editions, EMBASE, Australasian Medical Index and PsychINFO. There was no date restriction applied. In addition, the reference lists of all included studies were scrutinised for other potentially relevant studies.

SELECTION CRITERIA

Systematic reviews of randomised controlled trials (RCTs) and RCTs that compared the effectiveness of nursing interventions and considerations used in the administration of medications via enteral tubes. Other research methods, such as non-randomised controlled trials, longitudinal studies, cohort and case control studies, were also included. Exclusion criteria included studies investigating drug-nutrient interactions or the bioavailability of specific medications.

DATA COLLECTION AND ANALYSIS

Initial consideration of potential relevance to the review was carried out by the primary author (NP). Two reviewers independently assessed study eligibility for inclusion. A meta-analysis could not be undertaken, as there were no comparable RCTs identified. All data were presented in a narrative summary.

RESULTS

There is very limited evidence regarding the effectiveness of nursing interventions in minimising the complications associated with enteral tube medication administration in adults. The review highlights a lack of high quality research on many important nursing issues relating to enteral medication administration. There is huge scope for further research. Some of the evidence that was identified included that nurses should consider the use of liquid form medications as there may be fewer tube occlusions than with solid forms in nasoenteral tubes and silicone percutaneous endoscopic gastronomy tubes. Nurses may need to consider the sorbitol content of some liquid medications, for example, elixirs, as diarrhoea has been attributed to the sorbitol content of the elixir, not the drug itself. In addition, the use of 30 mL of water for irrigation when administering medications or flushing small-diameter nasoenteral tubes may reduce the number of tube occlusions.

Gastric tube placement in young children

In this study, the internal position of a nasogastric/orogastric tube was determined in 72 children, prior to an abdominal radiograph, by measuring CO2 and pH and bilirubin of tube aspirate. Fifteen of the 72 tubes (20.8%) were incorrectly placed on radiograph. Using the suggested adult cutoff of pH 5, pH of aspirate correctly predicted misplacement outside the stomach in 7/28 (25%) of children and correctly predicted correct placement in the stomach in 34 of 40 children (85%). Using the suggested adult cutoff of bilirubin > or = 5 mg/dL, bilirubin monitoring failed to identify either of two incorrectly placed tubes. In this study, using an algorithm of assuming stomach placement if the pH of aspirate is < or = 5 and obtaining an abdominal radiograph when either no aspirate is obtained or the pH is >5 would have resulted in 92% accuracy. Alternatively, obtaining an abdominal radiograph would result in nearly 100% accuracy.