BACKGROUND When the demand placed on the respiratory system is increased, the abdominal muscles become vigorously active to achieve expiration and facilitate subsequent inspiration. Abdominal muscle function could limit ventilatory capacity and a method to detect abdominal muscle fatigue would be of value. The maximum relaxation rate (MRR) of skeletal muscle has been used as an early index of t...

AIMS Bilateral pelvic neurectomy (BPN) interferes with delivery in rats. This work measures the effect of BPN on uterine and abdominal electromyography (EMG) and pressure during gestation and delivery. METHODS Uterine EMG and intra-uterine pressure (IUP), as well as abdominal muscle EMG and intra-abdominal pressure (IAP), were recorded on days 19-24 in rats. Mean values were determined for th...

Changes in intra-abdominal pressure during bowel tumor surgery have not been documented. The purpose of the present study was to analyze changes in intra-abdominal pressure (IAP), central venous pressure (CVP) and iliac venous pressure (IVP) in patients undergoing laparotomy due to large tumor of the bowel. Twenty-one adult patients undergoing elective abdominal surgery were examined. Intra-abd...

The anatomic structures in the female that prevent incontinence and genital organ prolapse on increases in abdominal pressure during daily activities include sphincteric and supportive systems. In the urethra, the action of the vesical neck and urethral sphincteric mechanisms maintains urethral closure pressure above bladder pressure. Decreases in the number of striated muscle fibers of the sph...

OBJECTIVES Central adiposity, insulin resistance and hypertension are clearly interrelated but the mechanisms underlying this association have not been thoroughly elucidated. As renal sodium handling plays a central role in salt-sensitive forms of hypertension, we investigated the relation of renal tubular sodium handling to abdominal adiposity, blood pressure and insulin sensitivity. DESIGN ...

No direct measurements of the pressures produced by the ribcage muscles, the diaphragm and the abdominal muscles during hyperventilation have been reported in patients with ankylosing spondylitis. Based on recent evidence indicating that abdominal muscles are important contributors to stimulation of ventilation, it was hypothesised that, in ankylosing spondylitis patients with limited ribcage e...

AIM The aim of the present study was to determine the nature and intensity of changes in the contractile activity and reactivity of gastrointestinal smooth muscle tissue in conditions of increased intra-abdominal pressure. METHODS A method for recording isometric contractions of isolated smooth muscle preparations from gastric corpus, duodenum and sigmoid colon of rats was used. RESULTS Two...

The addition of IAC to otherwise standard CPR provides for the application of external pressure over the abdomen in counterpoint to the rhythm of chest compression. Interposed abdominal compression is a simple manual technique that can supplement the use of adrenergic drugs to increase both coronary perfusion pressure and total blood flow during CPR. Mechanistically, manual abdominal compressio...