Consensus Definitions & Recommendations<\/strong><\/p>\nThe WSACS solicits your comments and recommendations regarding the following proposed consensus definitions on intra-andominal hypertension (IAH) and abdominal compartment syndrome (ACS).<\/p>\n
DEFINITIONS<\/strong><\/p>\nIntraabdominal Pressure (IAP):<\/strong><\/p>\n\n- Intraabdominal pressure (IAP) is the pressure concealed within the abdominal cavity. IAP varies with respiration.<\/li>\n
- Normal IAP is approximately 5 mmHg, but can be non-pathologically increased in the obese.<\/li>\n
- IAP should be expressed in mmHg (1 mmHg = 1.36 cmH2O) and measured at end-expiration in the supine position.\n
\n- Abdominal muscle contractions should be absent<\/li>\n
- The transducer should be zeroed at the level of the mid-axillary line<\/li>\n<\/ul>\n
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- The gold standard for direct<\/em> IAP measurement is via direct needle puncture and transduction of the pressure within the abdominal cavity (eg. during peritoneal dialysis or laparoscopy).<\/li>\n
- The gold standard for intermittent indirect<\/em> IAP measurement is via transduction of the pressure within the bladder.<\/li>\n
- The gold standard for continuous indirect<\/em> IAP measurement is via a balloon-tipped catheter in the stomach or via a continuous bladder irrigation method.<\/li>\n
- Abdominal perfusion pressure (APP) = mean arterial pressure (MAP) – IAP.<\/li>\n
- Filtration gradient (FG) = glomerular filtration pressure (GFP) – proximal tubular pressure (PTP) = MAP – 2 * IAP.<\/li>\n<\/ol>\n
Intra-abdominal Hypertension (IAH):<\/strong><\/p>\n\n- IAH is defined by either one or both of the following:\n
\n- An IAP > 12 mmHg, recorded by a minimum of two standardized measurements conducted 4-6 hours apart.<\/li>\n
- An APP < 60 mmHg, recorded by a minimum of two standardized measurements conducted 1-6 hours apart.<\/li>\n<\/ul>\n
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- IAH is graded as follows: \u00a0Grade<\/strong> Intraabdominal Pressure (IAP) <\/strong> I 12-15 mmHg II 16-20 mmHg III 21-25 mmHg IV > 25 mmHg<\/li>\n
- According to the duration of symptoms, IAH can be further classified into 4 groups:\n
\n- Chronic IAH<\/li>\n
- Acute IAH<\/li>\n
- Subacute IAH<\/li>\n
- Hyperacute IAH<\/li>\n<\/ol>\n<\/li>\n<\/ol>\n
Abdominal Compartment Syndrome (ACS): <\/strong><\/p>\n\n- ACS is defined as the presence of BOTH:\n
\n- An IAP > 20 mmHg with or without APP < 50 mmHg recorded by a minimum of three standardized measurements conducted 1-6 hours apart AND;<\/li>\n
- Single or multiple organ system failure which was not previously present<\/li>\n<\/ul>\n<\/li>\n
- In contrast to IAH, ACS should not be graded as it is an all or nothing phenomenon.<\/li>\n
- Primary ACS refers to:\n
\n- A condition associated with injury or disease in the abdomino-pelvic region that frequently requires early surgical or angioradiological intervention, OR<\/li>\n
- A condition that develops following abdominal surgery (such as abdominal organ injuries that require surgical repair or damage control surgery, secondary peritonitis, bleeding pelvic fractures or other cause of massive retroperitoneal hematoma, liver transplantation).<\/li>\n<\/ul>\n
Patients that undergo an initial trial of nonoperative management for solid organ injuries who subsequently develop ACS are included in the Primary ACS category.<\/p>\n
Former synonyms include “abdominal”, “surgical” or “acute”.<\/li>\n
- Secondary ACS refers to:\n