ABSTRACT
Objective To study the practicability of measurement of abdominal wall tension (AWT) for noninvasive monitoring of intra-abdominal pressure in ICU patients.Methods Patients with indwelling urethral catheter admitted to ICU from April 2011 to March 2013 were enrolled for a prospective study.Exclusion criteria were patients with muscular relaxants,abdominal operation in three months,acute peritonitis,abdominal mass,acute injury of urinary bladder,acute cystitis,neurogenic bladder,intrapelvis hematoma,and pelvic fracture.The AWT (N/mm) and urinary bladder pressure (UBP) (mm Hg) of all patients were measured.Statistical analysis was performed by SPSS 13.0 statistical software.The correlation of AWT and UBP were analyzed using linear regression analysis.The effects of respiration and body position on AWT were analyzed using the Paired-samples t test,and the effects of gender and body mass index (BMI) on basic level of AWT (IAP ＜ 12 mm Hg) were analyzed using the One-way ANOVA.Results A total of 51 patients were recruited in study.A significantly linear correlation between AWT and UBP were observed (R =0.986,P ＜ 0.01),the regression equation was Y =1.369 + 9.57X (P ＜ 0.01).Under the supine-flat positioning,the intra-abdominal pressures at the end of inspiration and the end of expiration were (1.65 ± 0.52) N/mm and (1.45 ± 0.54) N/mm,respectively,and under body straight up 30° supine positioning,the intra-abdominal pressures at the end of inspiration and the end of expiration were (1.25 ± 0.30) N/mm and (1.07 ± 0.35) N/mm,respectively.There were significant differences in intra-abdominal pressure between different respiratory phases and body positions (P ＜ 0.01).Basic levels of AWT in male and female were (1.09 ± 0.29) N/mm and (1.01 ± 0.34) N/mm.The basic levels of AWT in patients with BMI ＜ 18.5,18.5 ≤ BMI ≤25 and BMI ＞ 25 were (0.91 ± 0.30) N/mm,(1.02 ±0.35) N/mm and (1.16 ±0.28) N/mm respectively,but gender and BMI had no significant effects on basic level of AWT (P =0.457 and 0.313,respectively).Conclusions There was a significantly linear correlation between AWT and UBP,and respiratory phase and body position had significant effects on AWT,but gender and BMI had no significant impacts on basic level of AWT.AWT could be served as a simple,easy,and accurate method to monitor the IAP in critical ill patients.