[Normal values for solid state high resolution anorectal manometry in healthy adult volunteers]

Objective: To explore the normal values for two-dimension solid state high resolution anorectal manometry (HRAM) in healthy adult volunteers. Methods: The healthy adult volunteers were recruited by advertisement and underwent solid state HRAM in the left lateral position. Anorectal pressures and rectal sensation were recorded and analyzed. Results: (1) A total of 126 Chinese healthy adult volunteers (male: 50 cases (39.7%); age: (37.5±14.2) years old ) were recruited in this study. (2) Mean anal resting pressure (MERP) was (71.8±17.3) mmHg (1 mmHg=0.133 kPa). Maximum anal resting pressure (MARP) was (79.3±17.8) mmHg, Maximum anal squeeze pressure (MSP) was (178.7±52.8) mmHg. Anal high pressure zone (HPZ) length was (3.4±0.6) cm. During simulated evacuation, residual anal pressure (RAP) was (63.8±20.5) mmHg, and anal relaxation rate (ARR) was (37.0±11.5)%. Rectal threshold volume for first sensation (FST), desire to defecate (DDT), urgency to defecate (UDT) and maximum discomfort (MDT) was (47.4±10.0) ml, (84.5±18.2) ml, (125.8±28.5) ml, and (175.5±36.1) ml, respectively. (3) Compared with female subjects, male subjects had higher MSP[(211.0±50.7) mmHg vs (157.5±42.5) mmHg], RAP[(71.6±18.1) mmHg vs (58.8±20.5) mmHg]and rectal MDT[(187.0±36.4) mmHg vs (168.0±34.1)mmHg], but lower ARR[(32.1±8.0)% vs (40.2±12.3)%], all P<0.01. (4) MERP, MARP, MSP and rectal MDT were higher in young group (≤40 years old), all P<0.05. Conclusions: These observations provide normal values for two-dimension solid state HRAM, which have significant difference between genders and different age groups.