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Make the Diagnosis: Abnormal Central Venous Pressure
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Estimating the prior probability for an elevated CVP among patients with a low ejection fraction depends on the patient's underlying condition and the effectiveness of treatment. Current treatment regimens that now include β-blockers and angiotensin-converting enzyme inhibitors may decrease the prevalence of volume overload low in patients with a reduced ejection fraction. In the Studies of Left Ventricular Dysfunction, investigators determined clinically that approximately 10% of patients with a left ventricular ejection fraction 35% or less at baseline had an elevated CVP.3, 4 Although the CVP was not invasively measured, we know that clinical assessments of a high CVP typically underestimated the true value. As a starting point, the range 10% to 20% seems like a reasonable estimate for elevated CVP among patients previously diagnosed as having a low ejection fraction.
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The close relationship between low CVP and underlying disease makes it impossible to come up with a generally useful starting point for a pretest probability about CVP, so clinicians must use their own judgment individualized for the patient.
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Population for Whom an Abnormal Central Venous Pressure Should Be Considered
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Patients with a low left ventricular ejection fraction are at risk for a high CVP or a low CVP (eg, overdiuresis).
Patients with underlying acute clinical conditions that lead to volume loss may have a low CVP.
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Detecting the Likelihood of an Abnormal Central Venous Pressure
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