Intra-abdominal pressure may be decreased non-invasively by continuous negative extra-abdominal pressure (NEXAP)

• Published in: Intensive care medicine Vol. 29; no. 11; pp. 2063 - 2067
• Main Authors: VALENZA, Franco, BOTTINO, Nicola, CANAVESI, Katia, LISSONI, Alfredo, ALONGI, Salvatore, LOSAPPIO, Sabina, CARLESSO, Eleonora, GATTINONI, Luciano
• Format: Journal Article
• Language: English
• Published: Heidelberg Springer 01-11-2003; Berlin Springer Nature B.V
• Subjects: Abdomen; Aged; Airway Resistance; Analysis of Variance; Anesthesia. Intensive care medicine. Transfusions. Cell therapy and gene therapy; Biological and medical sciences; Blood Pressure; Catheterization, Swan-Ganz; Central Venous Pressure; Critical Care - methods; Critical Illness - therapy; Emergency and intensive care: digestive diseases. Bioartificial liver; Female; Heart Rate; Humans; Intensive care medicine; Lower Body Negative Pressure - adverse effects; Lower Body Negative Pressure - instrumentation; Lower Body Negative Pressure - methods; Lung Compliance; Male; Medical sciences; Middle Aged; Monitoring, Physiologic - instrumentation; Monitoring, Physiologic - methods; Regression Analysis; Respiration, Artificial - methods; Respiratory Mechanics; Tidal Volume; Urinary Catheterization; Human; Abdominal compartment syndrome; Central venous pressure; Intensive care; Continuous; Critically ill; Intra-abdominal pressure; Negative pressure; Pressure; Abdomen; Negative extra-abdominal pressure; Complication; Arterial pressure; Hemodynamics; Cardiac output; Technique
• ISSN: 0342-4642; 1432-1238
• DOI: 10.1007/s00134-003-2013-7

To investigate the possibility of artificially decreasing intra-abdominal pressure (IAP) by applying continuous negative pressure around the abdomen.
We investigated the effects of negative extra-abdominal pressure (NEXAP) on IAP and central venous pressure (CVP) in 30 patients admitted to our intensive care unit (age 57+/-17 years, BMI 26.1+/-4.0 kg/m2, SAPS II 41.8+/-17.0). Patients with severe hemodynamic instability and/or those admitted following a laparotomy were not studied. Measurements included bladder pressure as an estimate of IAP, CVP, invasive mean arterial pressure (MAP) and heart rate (HR). In five patients extensive hemodynamic measurements were also taken using a Swan-Ganz catheter. Following measurements at baseline (Basal), NEXAP (Life Care - Nev 100, Respironics) was applied on the abdomen, in random order, at a pressure equal to IAP (NEXAP0), 5 cmH(2)O (NEXAP-5) or 10 cmH(2)O (NEXAP-10) more negative than NEXAP0.
Basal IAP ranged from 4 to 22 mmHg. NEXAP decreased IAP from 8.7+/-4.3 mmHg to 6+/-4.2 (Basal vs NEXAP0 p<0.001). There was a further decrease of IAP when more negative pressure was applied: 4.3+/-3.2 mmHg, 3.8+/-3.7 mmHg (NEXAP-5 and NEXAP-10 vs NEXAP0, respectively, p<0.001). Similarly, CVP decreased from 9.3+/-3.4 mmHg to 7.5+/-3.8 (Basal vs NEXAP-10, p<0.001). The lower the IAP when NEXAP was applied, the lower the CVP (r2=0.778, p<0.001, multiple linear regression). When measured, cardiac output did not significantly change with NEXAP.
Negative extra-abdominal pressure may be applied in critically ill patients to decrease intra-abdominal pressure non-invasively.