DDS: 98-7 Recommendations to Prevent Aspiration Pneumonia

DMR MEDICAL ADVISORY #98-7
 
Recommendations to Prevent Aspiration Pneumonia
Prepared by Paul Dolinsky, MD
August 1998

PURPOSE:

To provide guidelines for staff in the prevention of aspiration pneumonia through application of appropriate evaluation and health care.

APPLICATION:

This advisory applies to clients of the department for whom the department bears direct or oversight responsibility for their medical care, regardless of the facility or region in which they are served.

The department recognizes the special need to work with facilities which it does not fund or license to ensure the thorough understanding and implementation of medical advisories.

I. Introduction

Aspiration pneumonia is a common cause of morbidity and mortality in the population of people with physical and mental disabilities. The normal swallowing mechanisms that protects the airway from solid or liquid material may be impaired in dysphagic individuals. Hence, unwanted substances enter the trachea and lung that can cause a chemical inflammation and subsequent infection that can result in pneumonia. This can lead to serious illness and is a common cause for death.

Current treatment options are available to help individuals who are unable to swallow effectively, although they may provide incomplete protection from recurrence of illness. The purpose of this guideline is to focus on the individuals who are at highest risk for aspiration illness and recommend a series of steps that should be considered in their evaluation and care.

II. Individuals at Risk for Aspiration Pneumonia

People with the more profound physical disabilities and neurologic impairment, with progressive need for increased care in daily activities (feeding and toileting) and limited mobility (unable to ambulate or maintain trunk or head posture) are at the greatest risk for aspiration. Common symptoms include coughing or choking during feeding or recurrent vomiting. However, some people aspirate material from their mouth into their lungs without any symptoms (silent aspiration). Also, there may be a poor correlation between the absence of a gag reflex and risk for aspiration. Individuals with mental retardation and physical disabilities who have had pneumonia from unknown causes should be considered possibly at risk for aspiration of oral contents.

III. Evaluation

The person, parent or guardian should be fully informed of the possibility of aspiration causing illness in the individual with mental retardation and be kept fully apprised of the evaluation and treatment options. One must be concerned in the individual with risk for aspiration, that if an enteral feeding tube is eventually recommended, the sensory stimulation associated with eating would be withdrawn. Taking away the pleasure of eating from someone could be a great loss. This must be balanced against the health benefits afforded to the individual by lowering the risk of aspiration pneumonia.

The initial step in a medical evaluation of a person at risk for aspiration is to perform a modified barium swallow study, preferably with the presence of a speech and swallowing occupational therapist and the radiologist. Modified diet and swallowing techniques could be offered, based on the results of the X-ray study. If the person does not have free aspiration of all consistencies of materials, attempts should be made to offer some nutrition, using the proper feeding instructions, to maintain the person's enjoyment of food. Individuals who are following a feeding program need to be observed for recurrences of aspiration illness. If they have further episodes of pneumonia, despite a feeding program, then they need to be considered for placement of a feeding tube.

Some individuals may have limited ability to fully maintain adequate nutrition orally because they can only safely (as determined by the speech and swallowing therapist and radiologist on review of the barium swallow study) eat a limited amount of food. It may be appropriate to consider placement of a feeding tube for nutrition while maintaining a limited amount of oral nutrition for pleasure.

An upper gastrointestinal barium contrast X-ray may be helpful in identifying anotomic abnormalities contributing to gastroesophageal reflux and subsequent aspiration. If gastric material reenters the esophagus, this represents a potential for aspiration into the trachea and lungs. Also, this study can detect hernias, strictures, ulcers, and tumors of the stomach.

The stomach and esophagus and duodenum can be visually inspected with an endoscope. The EGD (endoscopic gastro-duodenoscopy) would identify any ulcers or esophageal inflammation that would suggest the presence of reflux. Any lesions or blockages in the stomach and proximal duodenum could also be identified and biopsied if necessary.

A nuclear isotope test, gastric meal emptying study, is available which would document a delay in gastric emptying into the duodenum. Impaired peristalsis is a common problem in the severely physically and mentally impaired individual. This could lead to gastric distention and vomiting and would preclude the usefulness of a gastric fundoplication. However, the person must remain still for extended periods of time for proper imaging, which may limit its usefulness if the person is unable to fully cooperate.

Other tests available include esophageal manometry, which measures the pressure wave of peristaltic action into the stomach. Abnormal movement can be recorded, which may predict the potential success of an anti-reflux procedure. Acid monitoring with an esophageal pH probe can also identify episodes of gastroesophageal reflux, when acid backs up into the lower esophagus. This test usually requires patient cooperation, which may limit its application in the person with profound mental retardation.

IV. Feeding Tubes

Artificial nutrition via a tube can be used in a number of ways. A naso-gastric tube (placed through the nose into the stomach) can be used as a temporary means of providing nutrition. However, they can be uncomfortable, irritating the throat and nose. Also, they can be easily dislodged. If that occurs and material is introduced into the tube, aspiration into the lung may occur. The naso-gastric tube could be considered as a short term solution with proper monitoring of its use. An alternate method should be considered for a long term need.

The gastrostomy tube is the most common method of artificial long term nutritional support. The tube is placed through the abdominal wall into the stomach. Its placement can be accomplished by an interventional radiologist fluoroscopically, by a gastroenterologist performing esophagogastroduodenoscopy (upper endoscopy) or by a surgeon intraoperatively. The best method would be determined by the available expertise in the area and the anatomy of the patient. Individuals with severe physical deformities and kyphosis may need surgical intervention to safely place a feeding tube into the stomach.

A feeding tube passed into the jejunum, through the gastrostomy tube, may need to be considered in individuals in whom there is significant regurgitation of the stomach contents up into the esophagus or ineffective gastric emptying. Some individuals who have had a gastrostomy tube placed who present with recurrent vomiting or aspiration may benefit from a jejunostomy feeding tube. Percutaneously placed jejunostomy tubes placed by an interventional radiologist or operative placement by a surgeon are occasionally needed in difficult management situations. Also, jejunostomy tubes may need more nursing care than gastrostomy tubes and may be more difficult to replace if inadvertently dislodged.

Complications do occur with feeding tubes. They may become blocked or dislodged and require replacement or repositioning. Also, they may migrate distally into the digestive tract if not secured to the outside of the abdomen, and can cause an intestinal blockage. Improper insertion may occur, especially in the individual with distorted anatomy, which may lead to puncture of the intestine or other vital structure. Infections do occur around the insertion site that may require care. Further, ulcers may develop in the stomach where the inner tube irritates the intestinal lining.

V. Fundoplication

Filling the stomach with a liquid nutritional material from an artificial feeding tube may result in regurgitation into the esophagus and present the risk of aspirating that material into the respiratory tract. Hence, a surgical procedure that tightens the upper stomach, a fundoplication, had been developed to reduce the risk of reflux from the stomach into the esophagus. Current techniques allow this surgery to be performed through a laparoscope, which may reduce the morbidity. However, if the person has abnormal peristalsis from the esophagus into the stomach or impaired emptying of the stomach into the duodenum, the likelihood of success is greatly reduced and the procedure may be futile.

Individuals who have had a feeding gastrostomy tube placed and continue to have coughing, vomiting, or recurrent pneumonias should be evaluated for this procedure. It remains controversial whether the benefits of fundoplication should be offered to all individuals who require a feeding tube. At this time, a selected group should be considered for this surgical procedure. A fundoplication and gastrostomy feeding tube, in the appropriately selected person reduces, but does not eliminate, the possibility of recurrent aspiration. A direct jejunostomy tube may be considered in these circumstances. In the person with reflux and impaired gastric motility, a gastrostomy tube to drain the stomach secretions in combination with a feeding jejunostomy tube may be a useful technique to limit aspiration.

VI. Tracheostomy

Some clinicians have supported the use of having a protective tracheostomy placed to prevent aspiration of gastric and oral contents into the respiratory tract. A tracheostomy tube is placed from the neck into the trachea. The tracheostomy tube has a cuff or sleeve that can be inflated, thus preventing any material from penetrating the trachea from above. However, pressure from the inflated cuff may cause damage to the trachea. Also, the direct access from the environment into the trachea, bypassing the upper respiratory tract, may lead to increased infections. Further, a tracheostomy needs frequent nursing care with suctioning, being that it is harder for the person with a tracheostomy to clear secretions. This can result in substantial discomfort for the individual. Surgical procedures have been developed (tracheoesophageal anastomosis, laryngotracheal separation) that would physically separate the trachea from the esophagus so that oral contents could only pass into the stomach and all breathing is accomplished through a tube in the neck that leads into the trachea and lungs.

At this time, tracheostomy can not be generally recommended for the prevention of aspiration pneumonia, being that these complex procedures have not been demonstrated to reduce mortality in the population of people under consideration. However, there may be selected individuals for whom this may be considered.

VII. Gastrostomy Feeding Programs

The clinician should consider consulting with a nutritionist to determine the caloric and free water needs of the person who receives nutrition exclusively through the artificial tube. Many formulations are available, some of which offer advantages to people with specific problems.

Bolus versus slow infusion of the feeding material needs to be considered for people with gastrostomy tubes. Some studies have suggested a higher rate of aspiration in the bolus feeding approach due to gastric distention and limited gastric emptying. A jejunostomy feeding tube usually requires a slow infusion because there is no reservoir to accept a sudden bolus of material.

The position of the person is also important during and immediately after feeding. The advantage of gravity to aid in proper digestion needs to be considered. If the person is upright during feeding and the gastric phase of digestion, then there is a lower likelihood of reflux and regurgitation.


Attachments:

Appendix I: Summary Outline
Appendix II: References and Acknowledgements



Content Last Modified on 8/15/2007 11:29:00 AM