IAP is usually measured indirectly via the patient's bladder. The changes in intravesical pressure demonstrate an accurate reflection of intra-abdominal pressure (IAP).
Patients with two or more risk factors for IAH should have a baseline IAP performed and if elevated should have continued serial measurements.
IAP is measured 4 hourly or more frequently if IAP >12mmHg or the patient is hypotensive, has decreased urine output or a tense abdomen.
An increased IAP reading should be rechecked to ensure there is not a technical problem e.g. a blocked catheter.
If IAP > 12mmHg then medical management of IAH should be instituted in a timely manner to prevent further morbidity and mortality. Renal impairment can occur with IAP as low as 10-15mmHg.
Medical management will not be discussed in detail in this document but involves improving systemic perfusion, measures to reduce IAP, and in refractory cases early abdominal decompression. Excessive fluid administration should be avoided as it is strongly associated with ACS. The patient will need close clinical monitoring of organ function.