Update on Abdominal Compartment Syndrome

1. Update on Abdominal Compartment Syndrome Joint Hospital Surgical Grand Round Dr. Leung Tak Lun Canice Prince of Wales Hospital

3. Definition • Abdominal compartment syndrome (ACS) • adverse physiological consequences that occur as a result of an acute increase in IAP Burch et al. Surg Clin North Am 1996;76:834-422 • increased abdominal pressure with increased airway pressure, hypoxia, and oliguria Ivatury et al. Surg Clin North Am 1997;77:783-99

4. Definition • Primary ACS • abdominal injury is present • Secondary ACS • In patients with severe shock requiring massive resuscitation • Without abdominal injury

5. Risk Factors • Severe penetrating and blunt abdominal trauma • Ruptured abdominal aortic aneurysm • Retroperitoneal haemorrhage • Pneumoperitoneum • Neoplasm • Pancreatitis • Massive ascites • Liver transplantation • Abdominal wall burn eschar Crit Care 2000, 4:23-29

6. Pathophysiology • Pulmonary function • Mechanical • Decreased lung compliance • Increased pulmonary vascular resistance • Manifest as hypoxia, hypercapnia, increasing ventilatory pressure

7. Renal • Reduction in renal plasma flow • Direct pressure effect on the parenchyma • Activation of renin-angiotension system • In a prospective study • u/o < 0.5mL/kg/min in 65% patient with IAP between 16-25mmHg • Oliguric in 100% of patient with IAP > 35mmHg Meldrum et al Am J Surg 1997:174:667-72

8. Cardiovascular • Reduction in CO • Decreased venous return • Reduction in end-diastolic volume • Splanchnic blood flow decreased • Decreased cardiac output • Abnormal mucosal barrier, bacterial translocation, septic complication

9. CNS dysfunction • Elevation in ICP • Impaired venous outflow

10. Measurement?

11. Techniques • Direct • Catheter in the peritoneum • Indirect • Bladder • Stomach • Rectal pressure • Uterine pressure • Inferior vena cava pressure

12. Intravesical pressure measurement • First described by Kron in 1984 • Foley catheter • Instillation of 50ml normal saline • Clamped distal to the culture aspiration port • A 16G needle inserted into the aspiration port and connected to a 3-way connector or pressure tranducer • Pubic symphysis is used as the zero point

13. Management • Definitive treatment is decompressive laparotomy

14. Meldrum et al. Am J Surg.1997;174:667-672

15. Management • Decompress when • IAP persistently > 20mmHg Ivatury et al Sury Clinic North Am 1997;77:783-800 • IAP > 20mmHg with • U/O < 0.5ml/kg/min • PIP > 45mmHg • Oxygen delivery < 600 • IAP > 26mmHg Meldrum et al. Surg Clinic North Am 1997;77/801-11

16. Complications • Reperfusion Syndrome • Occurs when IAH is suddenly relieved • Sudden increase in tidal volume, causing respiratory alkalosis • Sudden increase of products of anaerobic metabolism • Arrhythmia and asystole

17. How to management the open abdomen?

18. Towel Clip closure

19. Bogota bag

20. Vacuum-assisted wound closure G.B. Garner et al. Am J Surg 2001;182:630-638

21. After the acute phase…………..

22. Primary closure could be carried out in 50-60% patient after 7-10days • Absorbable mesh and skin graft • Large ventral hernia • Require repair later

23. Bring Home Messages • ACS is a life-threatening condition • Mortality 10.6 -68% Crit care 2000, 4:23-29 • Early recognition and treatment is essential for improving outcome • Decompress when IAP > 20mmHg with deranged physiological parameter