What is normal intra-abdominal pressure?

The causes and effects of increased intra-abdominal pressure and abdominal compartment syndrome have been well documented. However, there have been no large series to determine normal intra-abdominal pressure in hospitalized patients. The purpose of this study was to determine normal intra-abdominal pressure in randomly selected hospitalized patients and to identify factors that predict variation in normal intra-abdominal pressure. A total of 77 patients were prospectively enrolled between September 1998 and July 1999. Data obtained included patient demographics (i.e., age, gender, height, weight, and body mass index), reason for hospitalization and bladder catheterization, previous and current surgical status, comorbidities, and intra-abdominal pressures. Intra-abdominal pressure readings were obtained through an indwelling transurethral bladder (Foley) catheter. Data were analyzed by analysis of variance and multiple regression analysis. There were 36 females and 41 males with a mean age of 67.7 years. Average weight, height, and body mass index were 79.6 kg, 1.70 m, and 27.6 kg/m2, respectively. Mean intraabdominal pressure was 6.5 mm Hg (range 0.2-16.2 mm Hg). Body mass index was positively related to intra-abdominal pressure (P < 0.0004). Gender, age, and medical and surgical histories did not significantly affect intra-abdominal pressure. However, using multiple regression analysis, a relationship between intra-abdominal pressure, body mass index, and abdominal surgery was discovered. Intra-abdominal pressure is related to a patient's body mass index and influenced by recent abdominal surgery. Thus, the normal intra-abdominal pressure can be estimated in hospitalized patients by using the derived equation. Knowledge of the expected intra-abdominal pressure can then by used in recognizing when an abnormally high intra-abdominal pressure or abdominal compartment syndrome exists.

Fatal airway compromise due to retropharyngeal hematoma after airbag deployment.

In trauma patients it is possible for a hematoma to form in the potential space between the pharynx and cervical spine (the retropharyngeal space). Fewer than 30 cases of actual airway obstruction secondary to retropharyngeal hematomas have been reported. We present an unusual case of an elderly woman who was involved in a minor motor vehicle collision which deployed her airbag. She died as a result of anoxic injury to the brain. Autopsy results demonstrated transverse fractures through the bodies of C5 and C7 with associated significant retropharyngeal and mediastinal hematoma. Airbags have been shown to significantly decrease the mortality rate in frontal collisions; however, the potential for hyperextension injuries from airbag deployment exists, especially if the occupant is unrestrained, small, or sitting too close to the airbag. When this woman's airbag deployed, it most likely caused her vertebral fractures, hematoma, subsequent airway compromise, and anoxic brain injury. Whatever the mechanism of trauma, one must be cognizant of the potential risk for retropharyngeal hematoma and airway compromise when a patient presents with injury to the cervical spine.

Ogilvie syndrome as a postoperative complication.

HYPOTHESIS: Ogilvie syndrome is a postoperative complication. DESIGN: Case series. SETTING: University-affiliated tertiary-care hospital. PATIENTS AND METHODS: The medical records of patients diagnosed as having Ogilvie syndrome after trauma or operation between 1989 and 1998 were reviewed. Medical charts were examined for history, treatment, cecal diameter, and outcome. MAIN OUTCOME MEASURES: Data were summarized in an attempt to identify patient populations at risk for Ogilvie syndrome. RESULTS: Ogilvie syndrome was diagnosed in 36 patients, 24 of whom were men. Average age at diagnosis was 68.9 years. Abdominal radiographs were obtained at time of diagnosis (mean cecal diameter, 13.4 cm; range, 8-20 cm). Operations preceding Ogilvie syndrome were orthopedic or spinal (n= 14), cardiothoracic (n= 12), abdominal (n= 5), and vascular (n= 2). Nonoperative trauma accounted for 3 cases. Coronary artery bypass grafting was the single most frequent procedure leading to Ogilvie syndrome (n=9 [25%]). Conservative treatment was successful in 52.8% of cases (n = 19). Twenty colonoscopic decompressions were performed on 13 patients, with an overall success rate of 77% (n= 10). Of the 3 patients in whom colonoscopic decompression failed, 2 died and 1 required operation. Five of the 36 patients required surgical intervention, with a mortality rate of 60% (n= 3). CONCLUSIONS: Previous studies have shown Ogilvie syndrome to occur most commonly after obstetrical/ gynecologic, abdominal/pelvic, and orthopedic procedures. Our data confirm that patients undergoing orthopedic and spinal procedures are at higher risk, but that the surgical procedure most commonly leading to Ogilvie syndrome was coronary artery bypass grafting. Cardiothoracic surgeons, orthopedic surgeons, and neurosurgeons should be cognizant of this complication in the patient whose abdomen becomes distended postoperatively. If recognized early and treated appropriately, pseudo-obstruction will resolve in most patients. If surgical intervention is required, the subsequent mortality rate is high.