2018 Section 6 - Laryngology, Voice Disorders, and Bronchoesophalogy

Chandrasekhar et al

Table 2. Guideline definitions for evidence-based statements. Statement Definition

Implication

Strong recommendation A strong recommendation means the benefits of the recommended approach clearly exceed the harms (or that the harms clearly exceed the benefits in the case of a strong negative recommendation) and that the quality of the supporting evidence is excellent (Grade A or B). a In some clearly identified circumstances, strong recommendations may be made based on lesser evidence when high-quality evidence is impossible to obtain and the anticipated benefits strongly outweigh the harms.

Clinicians should follow a strong recommendation unless a clear and compelling rationale for an alternative approach is present.

Recommendation

A recommendation means the benefits exceed the harms (or that the harms exceed the benefits in the case of a negative recommendation), but the quality of evidence is not as strong (Grade B or C). In some clearly identified circumstances, recommendations may be made based on lesser evidence when high-quality evidence is impossible to obtain and the anticipated benefits outweigh the harms. An option means that either the quality of evidence that exists is suspect (Grade D) or that well-done studies (Grade A, B, or C) show little clear advantage to one approach versus another.

Clinicians should also generally follow a recommendation, but should remain alert to new information and sensitive to patient preferences.

Option

Clinicians should be flexible in their decision making regarding appropriate practice, although they may set bounds on alternatives; patient preference should have a substantial influencing role. Clinicians should feel little constraint in their decision making and be alert to new published evidence that clarifies the balance of benefit versus harm; patient preference should have a substantial influencing role.

No recommendation No recommendation means there is both a lack of pertinent evidence (Grade D) and an unclear balance between benefits and harms.

a See Table 3 for definition of evidence grades.

Table 3. Evidence quality for grades of evidence. Grade

Evidence Quality for Diagnosis

Evidence Quality for Treatment and Harm

A

Systematic review of cross-sectional studies with consistently applied reference standard and blinding Individual cross-sectional studies with consistently applied reference standard and blinding Nonconsecutive studies, case-control studies, or studies with poor, nonindependent, or inconsistently applied reference standards

Well-designed randomized controlled trials performed on a population similar to the guideline’s target population Randomized controlled trials; overwhelmingly consistent evidence from observational studies Observational studies (case control and cohort design)

B

C

D X

Mechanism-based reasoning or case reports

Exceptional situations where validating studies cannot be performed and there is a clear preponderance of benefit over harm

patient with a preoperative voice abnormality should have laryn- geal examination as described in the next section. Importance of voice assessment. Voice impairment can sig- nificantly impact the ability of an individual to work, social- ize, and perform many activities of daily living. 10,11 It is important to establish the presurgical status of the patient’s voice characteristics and function for comparison postsurgi- cally, alert the surgeon to possible increased extent of disease, and determine the existence of preoperative voice problems that may remain postsurgically. Although the goal of this guideline is to optimize voice outcomes postoperatively, up to 33% of individuals may exhibit voice impairment preopera- tively. 70-72 Preoperative voice problems may result from tumor invasion of, or compression injury to, the RLN (as seen with,

eg, edema or large goiter), or from preexisting or non–thyroid- related causes. In addition, vocal fold edema or other tissue changes may be seen in endocrine abnormalities associated with thyroid problems. 73,74 One study demonstrated that indi- viduals identified with presurgical RLN impairment due to tumor invasion exhibited improved voice function outcomes after a subsequent voice surgery compared to those who were not so identified. 72 That same study also reported on 1 patient exhibiting preoperative unilateral vocal fold immobility who developed postoperative impairment of the previously normal vocal fold, resulting in bilateral vocal fold paralysis. Thus, baseline assessment of the patient’s voice prior to thyroid sur- gery serves the purpose of identifying those with preoperative impairment as well as establishing a preoperative reference

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