anal fistula (fistula in aÂ´no) one opening on the cutaneous surface near the anus, which may or may not communicate with the rectum. arteriovenous fistula one between an artery and a vein, either pathologic (such as a varicose aneurysm) or surgically created to ensure an access site for hemodialysis.
1 millibar (or hectopascal/hPa), is equivalent to 0.02953 inches of mercury (Hg). It is therefore only necessary to multiply a reading in millibars by the latter figure, to achieve the required conversion. E.g. for 1023 mbar, multiply by 0.02953=30.21 inches.
Atmospheric pressure at sea level is about 14.7 pounds per square inch, equivalent to 30 inches (760 millimetres) of mercury, 1,013.2 millibars, or 101,320 pascals. Of the many different varieties of mercury barometers, most variations arise from different techniques for measuring the height of the mercury column.