Pressureflow Studies

Pressure-flow studies are simultaneous measurements of detrusor pressure and urine flow rate (Figure 3-2.9). They provide more accurate and useful information than uroflow rate alone. The major goal of these studies is to diagnose outlet obstruction and distinguish obstruction from impaired detrusor contraction. Approximately 20 to 35 cm H2O of pressure is required to drive urine across the normal male urethra.14 Women void with lower detrusor contraction and pressure, and higher flow rates than men.15 Detrusor pressures more than 30 cm H2O typically indicate the presence of some degree of obstruction. No generally accepted pressure-flow criteria for obstruction in women exist.

The results of pressure-flow studies can be classified according to a number of nomograms. Most of these nomograms have been described in men because of the high prevalence of bladder outlet obstruction in this population. The drawback of these nomograms is the broad boundary between obstruction and nonobstruction. In Abrams-Griffith (ICS) nomogram, the Qmax and corresponding Pdet at the maximum flow rate are plotted against each other (Figure 3-2.10). The detrusor pressure is expressed in centimeters of water on the y axis and uroflow is expressed in milliliters/second on the x axis. The location of the plotted maximal flow point on the graph determines the presence, absence, or an equivocal state of obstruction.16

Figure 3-2.8. Rectal contractions may cause artifacts in detrusor pressure recording. Notice the stable vesical pressure during filling.

Figure 3-2.8. Rectal contractions may cause artifacts in detrusor pressure recording. Notice the stable vesical pressure during filling.

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Figure 3-2.9. Pressure flow in bladder outlet obstruction.

Üelrusor pressure (cm I IsO)

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Figure 3-2.10. The Abrams-Griffith nomogram depicting three pressure flow zones: obstructed, nonobstructed, and equivocal.

Herbal Remedies For Acid Reflux

Herbal Remedies For Acid Reflux

Gastroesophageal reflux disease is the medical term for what we know as acid reflux. Acid reflux occurs when the stomach releases its liquid back into the esophagus, causing inflammation and damage to the esophageal lining. The regurgitated acid most often consists of a few compoundsbr acid, bile, and pepsin.

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