EVIDENCE-BASED PRACTICE

The selection of any treatment for the patient with dysphagia should be based on the best available evidence from the published literature, the patient’s wishes, and the clinician’s experience with similar problems. The combination of these three variables in preparing a treatment plan is referred to as evidence-based practice (EBP). Given any individual patient, clinicians will assign different weights to each variable. For example, if the clinician has had excellent success with an unconventional form of therapy for which there is no research support, he or she may, with the patient’s consent, choose to apply that treatment strategy. Or if a patient did not feel able to cooperate with a recommended plan of treatment, another course of action may need to be implemented. EBP differs from traditional clinical management because it does not rely solely on clinical intuition and experience but also values patient desires and a critical appraisal of published research.

In all fields of health care, clinicians have been challenged to evaluate and use available research evidence to solve clinical problems and provide the best patient care possible in the most cost-efficient manner. Examples of how EBP affects patient care are numerous. For example, assume that a clinician had been using the tactile-thermal stimulation technique (see Chapter 14) with patients who show swallowing onset delay because of experimental evidence suggesting its application with that particular group of patients. However, when reviewing additional evidence in multiple studies with similar patients, the investigators reported that the effect was minimal. In this circumstance the clinician might be hesitant to apply the treatment. However, before changing practice, the clinician must evaluate the strength (believability) of the new evidence before he or she alters the treatment approach. Even in the face of strong evidence, some clinicians find it hard to abandon their own experience and intuition. Complete reliance on experimental evidence runs the risk of setting patient care guidelines and paths of care that experience suggests may not be in the patient’s best interest. The intersections of experimental evidence, clinical experience, and patient desires ultimately lead to the best treatment approach. When using an EBP model it is incumbent on the clinician to consult the research literature to evaluate treatment effectiveness or efficacy in patients similar to the one requiring evaluation or treatment.

Astute clinicians recognize that failure to implement EBP runs the risk of overusing familiar and comfortable treatments that might be less effective in achieving desired outcomes. Similarly, clinicians could be using what they perceive to be the most effective treatment strategy, but they are applying it incorrectly—for example, recommending that an exercise be done 10 times a day when the experimental evidence suggests that the best outcomes are achieved when it is done 100 times a day.

EVALUATING EVIDENCE

After the clinical and/or instrumental evaluation the clinician should be able to formulate questions (hypotheses) about which treatment approach might fit the patient’s profile. For example, if the patient was having difficulty protecting the airway during the swallow sequence, could he or she benefit from learning a swallowing maneuver, and would a change in posture be beneficial? A more focused question might be “Does the combination of a postural change and a swallowing maneuver help protect the airway, or is one intervention better alone?” Another relevant question might be “How long does the patient need to maintain these interventions before complete swallowing safety is achieved?”

The search for answers to questions could come from multiple sources, including personal experience (“It worked before so I will try it again”); textbooks (although these are rarely opened once the course is completed); expert advice through continuing education opportunities (“the expert said it, so it must be true”); commercial sales (“this is exactly what you will need”); and journal articles (although research has shown that the frequency of professional reading declines with years away from the university). All these sources, with the exception of the published journal articles, represent information that can be gathered. Information is different from evidence, because evidence results from a controlled approach to a clinical question.

Assuming the clinician wants to review the evidence pertaining to a clinical question, the next step would be to consult relevant databases using key search terms that might help answer those questions. Terms such as “posture,” “swallowing,” “outcomes,” and “treatment” might be used in the initial search. Finding the relevant evidence can be accomplished by using databases such as MEDLINE or PubMed, or Web sites that summarize data such as the Cochrane Library or the American College of Physicians. Typing terms in a Web search such as “evidence based” and “clinical trials” can lead to other relevant databases. Government-based Web sites such as www.guideline.gov (National Guideline Clearinghouse) can be a useful starting point in an evidence-based search. If the search is directed toward a specific disease such as Parkinson’s, accessing a specific organization’s official Web site also is a valuable point of departure.

After the evidence is accessed, the clinician must evaluate the relevance to the patient in question and its strength (believability) and clarity in guiding treatment. Judging the strength of the evidence is done through an analysis of the study’s design characteristics. Some Web sites (e.g., the Cochrane Library) are designed to provide critical reviews of the extant evidence on a multitude of diagnostic and treatment questions. Because these systematic analyses are designed to gather and grade the strength of many studies on a single topic, they are very useful for the busy clinician who may not have the time to do an extensive search. In the small subspecialty of oropharyngeal swallowing disorders, not every clinical question will have been reviewed systematically.

Because the study’s design often determines the relative strength of the evidence, it is important to know what constitutes weak evidence for any given outcome and what constitutes stronger evidence for the same outcome. Table 12-1 presents a classification system for grading levels of evidence according to the study’s design characteristics. For instance, the highest level of evidence (grade A or 1) is associated with study designs that are randomized, controlled trials (RCTs). A lower grade (grade D or 5) is associated with studies that report on a series of patients. Investigators who use the RCT design to study a question are bound by much stricter criteria to answer their question. In general, these criteria try to eliminate any bias in the study that might shed doubt on the believability of the results. Some of these criteria include a large sample size in an experimental and control group with subjects assigned randomly, measurements made by investigators who are blinded to the study, and accounting for the outcomes of all study subjects at the end of the experiment. Study designs at levels B, C, and D may meet some of these criteria, but not all of them. The fewer criteria met, the weaker the evidence. In general, a clinician would have more confidence in studies graded at grade A than at grade D. Therefore the applicability of the findings from RCTs would be applied clinically with more confidence than findings from studies that reported on similar outcomes with a case series design. Such criteria can help the clinician decide which diagnostic or treatment approach might fit the patient and how much confidence to place in the outcome. An extensive discussion of each level of evidence and its corresponding characteristics is beyond the scope of this chapter. Readers are referred to The Handbook of Evidence-Based Practice in Communication Disorders for a thorough discussion.¹

Judgment of the strength of the experimental evidence must be complemented by other analytic methods. For example, were the relevant studies done with patients similar to the patient in question, or were the characteristics in the reference sample different—such as age or gender? Was the treatment protocol in the study described precisely enough so that it could be replicated? Do you have the skills needed to replicate the treatment? For example, if the treatment described the use of certain equipment, do you have the equipment and are you trained to use it? And, finally, are the outcomes in the study similar to the ones you and your patient envision? Even the best-designed, grade 1 study may not be applicable to your clinical question. One also must judge whether the study under scrutiny has clinical significance. That is, if the conclusion from a study was that technique “X” improved hyoid elevation by 2 mm in a group of acute poststroke patients, is that change clinically significant or was it only a statistically significant difference? In this example, unless the study reported that a 2-mm change in hyoid elevation actually made a difference in airway protection or in an improvement of dietary intake, one may choose to ignore the data even though statistically technique “X” made a difference. Chapter 14 provides a more detailed discussion of study designs as they relate to answering clinical questions.

GENERAL TREATMENT CONSIDERATIONS

Two common considerations inherent to all aspects of dysphagia are airway protection and nutrition and hydration. Clinicians often face the important question, “Can the patient safely resume or increase adequate oral intake?” Dissecting this question reveals critical considerations in dysphagia treatment. The primary concerns for patients with dysphagia may be found in the words safe and adequate. Safety is often expressed in terms of airway protection. Patients who aspirate most of any given bolus of food or liquid are not considered safe in reference to the risk of aspiration and subsequent respiratory infection or, possibly, the risk of airway obstruction from more solid foods. The reference to adequate refers to the individual’s ability to ingest sufficient food or liquid by mouth to maintain (or increase, if required in the situation) nutrition and hydration. A patient who engages in total oral feeding only to ingest inadequate volumes of food or liquid is a patient who is at risk for future health problems. When patients are fed by nonoral routes, treatment should be focused on the potential to resume oral intake of food and liquid. If the patient is taking a total oral diet, the focus may be on expanding the amount of intake to enhance nutrition or on expanding the variety of the diet to improve social aspects of eating and presumably quality of life. In planning treatment, it is important to have a clear grasp of the patient’s present situation and a clear vision of where both clinician and patient want to be in the future and the factors that may help or hinder that direction.

In selecting any therapy, consideration must be given to the objective of that therapy. For example, in medicine one goal of therapy might be to cure a disease. How do clinicians “cure” dysphagia? Does curing dysphagia suggest that clinicians must return patients who are fed nonorally to oral feeding? This outcome is not always possible. Do clinicians want to prevent recurrence of a dysphagia-related comorbidity? One potential objective might be to diminish or eliminate recurrent chest infections. This goal certainly provides direction in treatment planning. In some situations clinicians may focus on limiting functional deterioration or facilitating recovery. To adopt this focus, clinicians must have a clear understanding of the underlying conditions contributing to dysphagia in individual patients. Certainly, clinicians hope that interventions do not contribute to later complications and that they, in fact, contribute to prevention of complications such as chest infections and malnutrition.

Beyond specific goals of treatment, clinicians must consider the nature of the swallowing deficit and the treatment options available to them and the patient (NOTE: these are not always the same). Box 12-1 summarizes some issues that might be addressed regarding the swallowing deficit. A basic question might revolve around feeding versus swallowing processes: Are there physical or cognitive factors that preclude successful feeding but that do not interfere with swallowing function? Are both of these factors present and, if so, do they interact in a positive or negative manner? Certain dysphagia-causing diseases might demonstrate differences between voluntary or involuntary motor processes. If differences are present, are there swallowing activities that may be used to tap into voluntary versus involuntary motor processes? Stage of deficit is an artificial delineation often used for convenience. Are the swallowing deficits primarily located within the oral, oropharyngeal, pharyngeal, or esophageal component? Clinicians must also remember that not only are these “stages” artificial, but that the swallowing mechanism is interactive—events occurring in one anatomic area have the potential to affect performance in another area (see Chapter 2). A difficult clinical task can be attempting to separate the specific swallowing deficit from any compensatory activities used by individual patients. For example, consider the patient who attempts to swallow but immediately begins to expectorate, or a patient who demonstrates a pattern of multiple, incomplete swallows interspersed with throat clearing, resulting in only a minute amount of material actually swallowed. Does this pattern reflect a specific pattern of impaired physiology? Does it reflect the presence of compensations intended to protect the airway, or are there other possibilities? In some cases, this distinction may not be important. However, in others, it may be important to understand what might be changed as a result of therapy versus what might not be changed. This consideration may affect the decision to engage in therapy and, if so, the direction of therapy.

Another noteworthy point is that dysphagia treatment is rarely unifocal. Dysphagia is the result of underlying disease or disorder processes. Consequently, patients with dysphagia often receive therapies from medical, surgical, and/or behavioral realms. Clinicians who are treating patients with dysphagia should be aware of concomitant treatments, as well as dysphagia treatments in other realms that may either work together or in place of behavioral treatment strategies the SLP may provide. Figure 12-1 is a schematic reminder of how these therapy categories may interact. In certain clinical situations one category may comprise the primary or sole treatment approach. In other situations two or all three categories may interact to form the most beneficial intervention.

PATIENT-SPECIFIC TREATMENT

Patients bring to any clinical situation a variety of unique circumstances. Box 12-2 provides a list of potential patient-related considerations that may have an impact on dysphagia treatment options and decisions. Because dysphagia is the result of underlying disease processes, the cause of dysphagia should be understood as best as clinically possible because the underlying disease presents a clinical course that has direct impact on swallowing function and benefits from various intervention strategies over time.

The severity of dysphagia is a more complex concept than might first be imagined. How is the severity of dysphagia graded? Some clinicians and investigators have used impairment of swallowing physiology based on instrumental examination,² whereas others have used more functional measures such as amount of food or liquid taken by mouth.^3,4 Some clinicians may believe that patients who take no food by mouth also have the poorest swallowing physiology. Unfortunately, this is not always the case. Patient status may change over time, and some patients who receive only nonoral feeding may actually have adequate swallowing physiology to ingest some food or liquid by mouth. Thus severity of dysphagia should not be considered a unitary concept because many factors are involved.

Eating history may provide clinicians with some idea of a patient’s motivation and willingness to push toward increased oral intake. This interacts directly with certain psychosocial considerations. For example, the patient who reports that he “lives to eat, not eats to live” and who engages in the practice of chewing food that cannot be swallowed just for the taste may be more compliant with a rigorous therapy plan than the patient who uses only nonoral sources and never attempts any oral intake of food or liquid. In addition, eating history may provide the clinician with cultural biases in food selection (i.e., the patient never ate that food or always ate that food) or limitations in specific food availability associated with the patient’s environment. Social aspects of eating should also be considered in terms of the patient’s current situation (“I attempt to eat alone in my room”) and future goals (“I would like to eat in a restaurant”). Finally, for patients who engage in both oral and tube feeding, eating history may explain the timing of one form of feeding relative to the other. This factor may be important in reaching functional goals in therapy.

The patient’s anticipated medical course is an essential factor for the clinician to understand. It may affect the consideration of whether to initiate therapy as well as which types of therapy to undertake. In some clinical scenarios it may be better to wait and monitor the patient’s condition (e.g., stability, endurance). In other situations aggressive therapy is indicated. Clinicians must keep in mind that therapeutic strategies should change as the patient’s underlying condition (and potentially dysphagia) changes.

Caregiver considerations are an extension of patient considerations, especially for patients (at any age) who are unable to perform self-care (including feeding). Whether the caregiver is a nurse, other qualified health care provider, spouse or other family member, or friend, caregiver performance can have a direct impact (positive or negative) on the performance of the patient with dysphagia. Mealtimes can become complicated by a caregiver who is uninitiated in proper feeding strategies for the dependent patient. Positioning of the patient, rate and manner of food presentation, and other variables need to be clearly understood by caregivers.

The patient’s residential environment also can affect the nature of dysphagia interventions (see Chapter 1). The needs of the patient in the intensive care unit are different from those of the individual receiving outpatient therapy. In addition, the resources available in different environments differ dramatically. Clinicians working in academic medical centers often have more resources available than do clinicians working in rural long-term care facilities.

APPROACH-SPECIFIC TREATMENT

Treatment techniques (including medical, surgical, and behavioral), like individual patients, require specific consideration in planning intervention. As previously mentioned, treatment options change as the patient’s condition changes over time. From this perspective the decision of when to intervene, as well as how to intervene (choice of technique), changes according to the patient’s condition. In general, treatment strategies may be considered in reference to the degree of interaction with the patient and/or the intent of treatment. A common approach to patients who are severely debilitated or in the acute phase of an illness is a prophylactic or preventative approach. Such approaches often tend to be passive, not requiring substantial activity from the patient. Oral hygiene, passive movements, and perhaps diet changes might be considered passive interventions. Active interventions are those in which the patient is required to engage in direct maneuvers or compensations to change some aspect of swallowing performance. Another dichotomy that may overlap with active versus passive interventions is that of patient-centered versus environment-centered interventions. Patient-centered interventions may be active or passive, but all focus on the patient. Environment-centered interventions are primarily passive, with the focus on changing some aspect of the patient’s environment. Dining rooms or special mealtimes for patients with dysphagia are examples of environment-centered interventions.