Definitions for the strength of evidence (Class I-III) and strength of recommendations (A-C) are repeated at the end of the "Major Recommendations" field.
Are emergency department (ED) blood pressure readings accurate and reliable for screening asymptomatic patients for hypertension?
- Level A recommendations. None specified.
- Level B recommendations. If blood pressure measurements are persistently elevated with a systolic blood pressure greater than 140 mm Hg or diastolic blood pressure greater than 90 mm Hg, the patient should be referred for follow-up of possible hypertension and blood pressure management.
- Level C recommendations. Patients with a single elevated blood pressure reading may require further screening for hypertension in the outpatient setting.
Do asymptomatic patients with elevated blood pressures benefit from rapid lowering of their blood pressure?
- Level A recommendations. None specified.
- Level B recommendations.
- Initiating treatment for asymptomatic hypertension in the ED is not necessary when patients have follow-up
- Rapidly lowering blood pressure in asymptomatic patients in the ED is unnecessary and may be harmful in some patients
- When ED treatment for asymptomatic hypertension is initiated, blood pressure management should attempt to gradually lower blood pressure and should not be expected to be normalized during the initial ED visit.
- Level C recommendations. None specified.
Definitions:
Strength of Evidence
Class I - Interventional studies including clinical trials, observational studies including prospective cohort studies, aggregate studies including meta-analyses of randomized clinical trials only
Class II - Observational studies including retrospective cohort studies, case-controlled studies, aggregate studies including other meta-analyses
Class III - Descriptive cross-sectional studies; observational reports including case series and case reports; consensus studies including published panel consensus by acknowledged groups of experts
Strength of Recommendation
Level A recommendations. Generally accepted principles for patient management that reflect a high degree of clinical certainty (i.e., based on strength of evidence Class I or overwhelming evidence from strength of evidence Class II studies that directly address all the issues)
Level B recommendations. Recommendations for patient management that may identify a particular strategy or range of management strategies that reflect moderate clinical certainty (i.e., based on strength of evidence Class II studies that directly address the issue, decision analysis that directly addresses the issue, or strong consensus of strength of evidence Class III studies)
Level C recommendations. Other strategies for patient management based on preliminary, inconclusive, or conflicting evidence, or, in the absence of any published literature, based on panel consensus
There are certain circumstances in which the recommendations stemming from a body of evidence should not be rated as highly as the individual studies on which they are based. Factors such as heterogeneity of results, uncertainty about effect magnitude and consequences, strength of prior beliefs, and publication bias, among others, might lead to such a downgrading of recommendations.