The frail elderly often require tubefeeding for a variety of reasons. These feedings may be given by gastrostomy or jejunostomy, but more commonly are administered by the nasogastric route. Improved techniques are making the latter practice safer, more nutritionally sound, and more comfortable for the patient. But, it is important that nurses assess their practices in order to be sure that optimum patient care is the outcome.
The newer weighted tubes are not only more comfortable, they also make the swallowing of secretions and food or drink much easier. This is an important consideration for those frail elderly clients who may need only temporary nasogastric tube-feeding to supplement dietary intake.
The use of small-bore weighted stomach feeding tubes is relatively new and many extended care or geriatric institutions do not routinely utilize these devices. Many nurses are still unfamiliar with the indications for usage and the procedures regarding these tubes. The purpose of this retrospective study was to determine whether or not the new small-bore tubes result in fewer nasogastric tube-related infections and therefore , whether or not they are safer. The problem statement can be posed as a question. Compared to large-bore Levin-type feeding tubes, are small-bore weighted nasogastric feeding tubes associated with fewer respiratory tract infections?
The geriatric nurse should give particular attention to vulnerabilities that make older people dependent on and susceptible to domination by healthcare personnel, and to methods and conditions needed to preserve human dignity and safety. Within this framework, the principles of sanctity of life, dependency, and caring are woven into a basic ethical concept that becomes part of nursing practice. In the geriatric setting, nasogastric tube feedings are given to dependent vulnerable older people. Often, these feedings jeopardize their safety and cause excess morbidity and mortality.
This article examines 20 patients who acquired respiratory tract infections while receiving nasogastric tube feedings, and compares those infections associated with the newer smallbore weighted tubes to those with conventional larger Levin-type feeding tubes. Research questions include the following:
Compared to Levin-type tubes:
1. Are small-bore tubes associated with fewer upper respiratory tract infections?
2. Are small-bore tubes associated with fewer pneumonias?
3. Of the pneumonias, are smallbore tubes associated with fewer episodes of tube displacement and/or aspiration?
Tube-feeding must be considered without delay whenever the nutrition of the frail elderly client is in question. Unless nutritional support is started early, the client may suffer deficits that increase mortality.1 The cost of treatment for malnutrition-related illnesses (such as infections that occur more easily due to a stressed immune system) is greatly increased, and the morbidity and patient distress certainly affects that patient's quality of life. Benign neglect of inadequately nourished frail elders can significantly shorten their life span.
Patients who should be considered for nasogastric feeding are those who are unable to eat because they have swallowing difficulties and choke easily. They may have compromised access to the normal gastrointestinal tract (cancer of the head and neck), or they may have functional or metabolic abnormalities (malabsorption, pancreatitis, radiation enteritis). Patients who have hypercatabolic states (major sepsis, trauma, or surgery) or those who require higher amounts of calories or protein than they are able to ingest are also candidates. Candidates for tube feeding must, of course, have a normal gastrointestinal anatomy or at least partial digestive/absorption function of some small bowel.2
The new small-bore weighted tubes can be used for either gastric or duodenal feeding, depending on their length and design. Either way, the tubes are inserted into the patient's stomach. For gastric feeding, the tube is simply taped in place and feedings begin when placement is confirmed. Duodenal tubes are taped slack so that they will pass into the duodenum with peristalsis. Patients are usually positioned on their right side for up to 24 hours, after which placement is confirmed by x-ray.3
The ideal way to feed the patient by nasogastric route would perhaps be the continuous method, so as to minimize undesirable side effects and maximize absorption. A pump for regulating the flow of the feeding can also reduce the effect of the tube becoming blocked. Most patients, however, find this method too restrictive. Nurses also tend not to like this method for the elderly since it makes mobility and social interaction difficult. It is, therefore, usually reserved for those few patients who cannot tolerate the fairly large amounts given during intermittent feedings.
Intermittent feeding schedules depend on the patient's condition. If he has a fully functioning gastrointestinal system and gag reflex, feedings can be given three to six times per day. Intermittent feedings are generally given by a gravity administration set with the flow rate adjusted so that the feeding is completed within one hour. Thorough tube irrigation after feeding is necessary to prevent clogging. Great care must be taken when administering medications. These must be in liquid form or completely crushed and dissolved.3 Because the flexibility of the small weighted tubes makes them more difficult to insert, many have a lubricantbonded tip, and most have a stylet for ease of insertion.
Complications associated with nasogastric feedings may be classified as mechanical, gastrointestinal, and metabolic.4 With newer thin-weighted tubes, tube displacement after coughing seems to occur less often than with large-bore tubes. Large tubes also seem to decrease the gastroesophageal sphincter competence.
These large Levin-type tubes (size 14 to 18 French) are almost always associated with distal esophageal irritation from esophageal reflux and peptic esophagitis.5 If newer weighted tubes are not available, a number 6 or 8 French feeding tube may minimize these problems; but the problem of tube displacement will still exist or may actually increase, since these small unweighted tubes do not stay down as well as do the newer small weighted tubes.
Aspiration pneumonias may occur if gastric contents from vomiting or reflux enter into the bronchus. Delayed gastric emptying is inhibited by high nutrient density formulas, hypo- and hyperosmolar solutions, and cold formula. Certain drugs and pathological conditions such as diabetes, pancreatitis, malnutrition, or vagotomy may predispose the nasogastric tube-fed patient to aspiration.
Patients in the study had acquired respiratory tract infections associated with nasogastric feeding tubes. They were male geriatric clients from extended care units of a Veterans Administration Medical Center. These 20 clients were unable to eat due to swallowing difficulties, usually because of cerebrovascular accidents with severe impairment, or because of brain trauma or chronic dementia and resultant obtunded or comatose states.
These respiratory tract infections associated with nasogastric tube feeding usage occurred during a six-month period beginning March 1 and ending August 31, 1986. The source of information about these cases was the list of nosocomial infections compiled by the infection control nurse during the sixmonth time period. Information criteria on the list included primary diagnosis, type of respiratory infection, evidence of possible aspiration or choking, culture and antibiotic sensitivity results, and type of feeding tube in use.
For all patients in the study group, nasogastric feeding tubes had been inserted for intermittent feedings into the stomach. Both large-bore Levintype tubes and weighted small-bore tubes were in use on the extended care units. The small-bore weighted tubes included a stylet for insertion ease.
Tube-feeding procedures for both types of nasogastric tubes included routine nursing measures such as checking for tube placement prior to beginning the feeding, elevating the head of the bed by at least 30° during the feeding and for 30 minutes after, and feeding by gravity at room temperature with feeding completed within one hour. Commercial formulas packaged in 250 ml glass containers were used with administration sets. Administration sets were flushed with 50 ml of water following each feeding and discarded after 24 hours. Gastric volume was checked for those clients with large-bore tubes by aspirating stomach contents prior to feeding and holding the feeding and consulting the physician if contents already in the stomach exceeded 150 ml.
This method of checking for retained feeding cannot always be used for small-bore tubes because they tend to collapse with aspiration. These clients were observed instead for signs and symptoms of retention such as nausea, abdominal distention, or cramps. Intermittent feedings were given according to each individual diet order throughout the 24-hour period and additional water intake was given according to individual need based on urinary output, feeding osmolality (concentration of high solids that can result in dehydration), and fever or extensive tissue breakdown. Maintaining accurate intake and output may be difficult with incontinent patients, but attempts are necessary to ensure hydration.
Good mouth care, at least twice daily, was encouraged for all tube-fed patients. Cleansing and plaque removal were followed by the application of artificial saliva to lubricate the mucous membranes. Frequency of mouth care depended on whether or not the patient was a mouth-breather and prone to drying. Nostrils were cleaned and lubricated during mouth care, and tape position was changed
Numbers and types of nasogastric feeding tube-associated respiratory tract infections are displayed in the Table. Fourteen (70%) of the 20 nasogastric feeding tube-associated respiratory tract infections were associated with large-bore Levin-type feeding tubes. Twelve of the 14 (86%) were pneumonias, and five (42%) of these pneumonias were associated with evidence of tube displacement and/or aspiration. In one case, the tube was found coiled in the oropharynx, one patient had emesis, one had pulled out the tube, and two had had apparent régurgitation as evidenced by tube feeding being suctioned from the oropharynx.
NASOGASTRIC FEEDING TUBE-ASSOCIATED INFECTIONS
Of the six (30%) infections associated with small-bore weighted feeding tubes, four (66%) were pneumonias, with two (50%) of these pneumonias associated with possible tube displacement/aspiration. One patient had a prepneumonia event that involved the suctioning of tube-feeding from the oropharynx during routine suctioning. In addition to this régurgitation and possible aspiration, the other patient pulled out his feeding tube and probably aspirated.
Of the 20 infections, four (20%) were upper respiratory tract infections. Two of these were otitis media, one with a small tube and one associated with a large tube. One pharyngitis with a small tube followed colonization with a multiresistant bacteria. One other patient with a large tube developed a bacterial pharyngitis.
During the six-month study period, a total of 42 elderly patients in the medical center received nasogastric tube feedings. Twenty patients had smallbore weighted tubes inserted, and 22 patients had large-bore Levin-type tubes inserted. In these 42 patients, a total of 16 pneumonias resulted from tube displacement and/or aspiration. Four of the pneumonias occurred in patients with small-bore tubes (20% of the small-bore tubes in use resulted in pneumonia). Twelve of the pneumonias occurred in patients with large-bore tubes (54.5% of the large-bore tubes in use resulted in pneumonia) (see Table).
With intermittent nasogastric tube feeding, tube size and type appears to be a significant factor related to pneumonia and the predisposition of the tube for displacement and/or aspiration.
The avoidance of complications should be a primary concern whenever nasogastric nutritional therapy is used. Patient well-being is even more an imperative when one considers that the elderly above age 70 have a nosocomial infection rate that is about ten times that of patients below age 50. 6
Procedures that guarantee optimum safety for the frail elderly will become even more important in the future. Care will shift in the coming decade into the community, and most elders will be maintained as much as possible outside of institutions. Patients who are hospitalized or who reside in nursing homes or extended care facilities will be seriously ill and/or severely debilitated.
Since nosocomial pneumonias cause significant morbidity and mortality, and are the most common cause of death resulting from nosocomial infections, avoiding pneumonia as a complication of nasogastric tube feeding should be a major concern of hospital and extended care facility nurses. Suffering brought about by nosocomial pneumonia can be devastating. The patient's oxygen requirements, breathing patterns, cardiovascular integrity, and nutrition and hydration become greatly altered. Should the frail elderly client survive such a bout, he/she will surely suffer irretrievable physical and possibly mental losses. The quality of life can be altered for the worse even if the pneumonia clears.
Under prospective payment, a hospital receives a set reimbursement for treating each patient. If the facility keeps its cost below that set limit, it retains the difference in money; but when costs exceed the reimbursement, the hospital must simply absorb the loss. Thus, every penny spent in treating a nosocomial pneumonia, including the expense of added hospital days, comes out of the hospital's pocket.
What is important to realize is that older age itself (either 65 years or older, or 70 years or older) can be considered a comorbid condition that pushes a patient's designation from one category to another. A patient who is already in a new diagnosis-related group by virtue of old age will not be further reimbursed if a nosocomial infection ensues. Thus, if the new diagnosisrelated group does not take into account sufficient extra days for hospitalization for both older age and a nosocomial infection, then the costs for caring for the elderly patients who do become infected will add a tremendous economic burden to the hospital. More specifically, if elderly patients require more time in the hospital for the same diagnosis than those who are younger, regardless of the presence or absence of infection, there will be no extra reimbursement for up to 43% or more of nosocomial infections in some hospitals.6
Nosocomial pneumonias generally account for approximately 15% of all nosocomial infections. Although these infections represent only a modest proportion of hospital-acquired infections, they are associated with higher excess hospital costs than any other type of nosocomial infection. The average cost of treating a nosocomial pneumonia can be estimated at from between $1,255 to $2,8637 and $4,000.8
Not all patients are at equal risk of acquiring pneumonia during hospitalization. Risk factors that have been associated with acquisition of nosocomial pneumonia include: 1) colonization of the oropharynx and upper airways with gram-negative bacilli (an event that can be aided by the presence of upper airway invasive devices such as large-bore feeding tubes); 2) conditions that favor aspiration of oropharyngeal secretions (such as large feeding tubes which make swallowing oral secretions difficult); 3) prolonged preoperative stays; 4) surgical procedures involving the thorax or upper abdomen; 5) prolonged surgical procedures in general; 6) continuous mechanical ventilation; and 7) various host factors such as increasing age and chronic obstructive pulmonary disease.7
Attempts to prevent nosocomial pneumonia have been based on techniques designed to improve host defenses, prevent colonization of the upper respiratory tract with gram-negative bacilli, and reduce the likelihood that patients will aspirate or inhale pathogenic organisms. This study indicates that large-bore Levin-type feeding tubes make it more likely that patients will aspirate and acquire pneumonia. Twenty patients were given tube feedings via small-bore feeding tubes. Four of these patients (20%) developed pneumonia. Twenty-two patients were given tube feedings via large-bore Levin-type tubes, and 12 developed pneumonia (54.5%).
The research questions were answered in this study as follows:
1 . Small-bore tubes were associated with fewer upper respiratory tract infections.
2. Small-bore tubes were associated with fewer pneumonias.
3. There were fewer instances of evidence of tube displacement and/ or aspiration with small-bore tubes.
The use of improved small-bore weighted nasogastric feeding tubes is one way to meet the prevention criteria when providing enterai nutritional support to the frail elderly. In this study, in answer to the problem statement, weighted small-bore nasogastric feeding tubes were associated with fewer pneumonias.
- 1. Kaminski MV: Open letter. Nutritional Suppon Services 1985; 6(4):51.
- 2. Royal Marsden Hospital: Clinical forum: Procedures for nasogastric feeding. Nursing Mirror 1984; I58(2):I-8.
- 3. Guiness R: How to use the new small-bore feeding tubes. Nursing 86, 1986; I6(4}:51-S6.
- 4. Haynes-Johnson V: Tube feeding complications: Causes, prevention, and therapy. Nutritional Support Services 1986; 6(3):17-24.
- 5. Griggs GA, Hoppe MC: Update nasogastric tube feeding. AmJNurs 1979; 79(3):481-485.
- 6. Wenzel RP: Nosocomial infections, diagnosis-related groups and study on the efficacy of nosocomial infection control. Am J Med 1985; 78<suppl 6B):3-6.
- 7. Boyce JM: Cost-effective application of the CDC guideline for prevention of nosocomial pneumonia. Am J Infecí Control 1985; 13(5):228-232.
- 8. Troxler S: Under DRG's nosocomial infections. Hospital Infection Control 1985; 12(ll):141-142.
NASOGASTRIC FEEDING TUBE-ASSOCIATED INFECTIONS