Abdominal Compartment Syndrome

1. Abdominal Compartment Syndrome By Sharra Way - Bingham, RN

2. ? What it is ? A disease process that dramatically increases organ failure and death for medical and surgical ICU patients

3. Abdominal Compartment syndrome occurs as a result of the accumulation of fluid in the abdominal space from trauma or surgical procedures, or the increasing of abdominal contents due to tissue edema from an inflammatory process or massive fluid resuscitation or from tumor growth As this pressure increases within the abdomen capillary perfusion is compromised and tissue ischemia and/or death occurs If undetected or untreated multi-organ failure and patient death may ensue

4. Objectives • Differentiate between intra-abdominal hypertension (IAH) and abdominal compartment syndrome (ACS) • Identify patient populations at risk for IAH/ACS • Understand the pathophysiological process of IAH/ACS • Discuss appropriate procedures for assessment of abdominal pressure

5. Objectives • Anticipate clinical considerations for management of IAH/ACS

6. What is a normal intra-abdominal pressureorIAP This is the pressure within the abdominal cavity 5 – 7 mmHg is normal in a critically ill adult

7. Intra – abdominal Hypertension IAH • Defined as sustained or repeatedly elevated abdominal pressure • >12 and is graded

8. Grades of IAH • Grade I 12 – 15 mmHg • Grade II 16 – 20 mmHg • Grade III 21 – 25 mmHg • Grade IV >25 (ACS)

9. IAH • Sustained pressure, >12 that has significant effects on abdominal organs and cardiac output with subsequent dysfunction of both abdominal and extra-abdominal organs

10. Understanding Abdominal Compartment Syndrome • APP – Abdominal perfusion pressure • MAP – Mean arterial pressure • IAP – Intra-abdominal pressure • APP = MAP – IAP • A critical IAP that leads to organ failure is variable by patient & a single threshold cannot be applied globally to all patients • APP is superior to IAP, arterial pH, base deficit & lactate in predicting organ failure & patient outcomes

11. Definition of ACS • A sustained IAP > 20 mmHg (with or without an APP of <60 mmHg) that is associated with new organ dysfunction/failure • Adverse physiological effects caused by massive interstitial and retroperitoneal swelling which leads to organ or multi-organ failure • Historically IAPs as high as 40 mmHg had been acceptable; therefore, most clinicians are concerned when IAP reaches 20 – 25 mmHg

12. Abdominal Compartment Syndrome • Primary ACS – associated with injury or disease in abdomen/pelvis requiring early surgical or interventional radiological screening • Secondary ACS is from conditions not originating in the abdomen/pelvis • Recurrent ACS is the redevelopment of ACS following previous surgical or medical treatment of primary or secondary ACS

13. Common Causes of ACS • Primary causes • Abdominal trauma with bleeding • Pancreatitis • Ruptured abdominal aortic aneurysm • Retroperitoneal hematoma • Obstructions/ileus • Pneumoperitoneum • Abcesses • Visceral edema

14. Common Causes • Secondary Causes • Acute respiratory distress syndrome • Major trauma or burns • Massive fluid resuscitation • Hypothermia <33 degrees Celsius • Acidosis with pH < 7.2 • Hypotension • Massive blood transfusion > 10 units • Coagulopathy • Sepsis

15. Common Causes • Chronic Causes • Obesity • Liver failure with ascities • Malignancies

16. Physiologic Insult/Critical Illness Ischemia Inflammatory response Fluid resuscitation Capillary leak Tissue Edema (Including bowel wall and mesentery) Intra-abdominal hypertension

17. Pathophysiological Consequencesof ACS • Cardiovascular • Reduced Cardiac Output • Compression of the inferior vena cava and portal vein • Reduced blood return to the heart • Afterload increased from mechanical compression of vascular beds and vasoconstriction

18. Pathophysiology • Cardiovascular • Reduced Stroke volume • Tachycardia • Increased pressure on great vessels making hemodynamic monitoring challenging with falsely elevated and misguiding pressures • Increased risk for thromboembolic events secondary to venous stasis

19. Pathophysiology Pulmonary • Reduced lung compliance secondary to diaphragmatic elevation leads to • Hypoventilation and ventilation-perfusion mismatch • Increased work of breathing • Hypoxia and hypercarbia • Mechanical ventilation often required

20. Pathophysiology • Respiratory • Increased peak airway secondary to decreased lung compliance • Increased risk of barotrauma

21. Pathophysiology • Renal • Increased IAH leads to decreased renal blood flow and decreased glomerular filtration • Oliguria may be observed with IAP of 15 - 20 • An IAP of >30 leads to anuria • Increase of antidiuretic hormone and activation of renin-angiotensin-aldosterone system • Increased water retention

22. Pathophysiology • Abdominal Visceral • Reduced blood flow which leads to • Intestinal ischemia • Decreased blood flow to all abdominal organs

23. Pathophysiology • Central Nervous System • Increased thoracic and central venous pressure leads to • Decreased cerebral outflow of blood • Increased intracranial pressure which leads to decreased cerebral perfusion pressure

24. Measuring Intra-Abdominal Pressure

25. Importance of accurate measurement • Physical examination yields low levels of detection of IAH/ACS • Early detection and intervention reduces morbidity and mortality. • Diagnosis is dependent on frequent and accurate measurement of IAP (watching trends) • Cost effective, safe and accurate

26. Assessment Guidelines • New ICU admission • Evidence of clinical deterioration • Pt has two risk factors for IAH/ACS • Decreased abdominal wall compliance • Increased intra-luminal contents • ileus, gastroparesis, obstruction • Increased abdominal contents • Pneumoperitoneum, hemoperitoneum, ascities, liver dysfunction • Capillary Leak/fluid resuscitation

27. IAH/ACS Assessment algorithm from World Society of Abdominal Compartment Syndrome (WSACS) www.wsacs.org Excellent references

28. Types of Measurements • Direct Pressure via intraperitoneal catheters • Indirect Pressure • Gastric Measure • IVC • Rectal • Urinary bladder pressure – Gold Standard

29. Urinary Bladder Pressure Most technically reliable Correlate closely with pressures measured directly in the abdominal cavity Reliably reproducible Transduced through a Foley catheter

30. Intermittent Monitoring • Open Systems • Closed Systems

31. Equipment needed for open measurement • Disposable transducer • 12” pressure monitoring tubing • 4-way stopcock • Red dead-ender • 60 cc, lure-lock syringe, sterile • Sterile normal saline • Clamp, non-sterile • Level

32. Procedure for open, intermittent monitoring • Collect and gather all supplies • Attach stopcock to end of sterile transducer • Important to maintain sterile technique to avoid contamination and potential infectious process

33. Procedure for open, intermittent monitoring • Attach pressure tubing to the remaining end of the transducer

34. Procedure for open, intermittent monitoring • Fill 60 cc syringe with 40 cc of sterile normal saline • Attach syringe to side port of the stopcock • Flush stopcock, pressure tubing and transducer with the normal saline ensuring all air is removed

35. Procedure for open, intermittent monitoring • Clamp the urinary drain tubing distal to the sampling port • Cleanse the sampling port with alcohol • Using sterile technique attach the pressure tubing to the LuerLok connecting sampling port of the urinary catheter

36. Procedure for open, intermittent monitoring • Instill 25 cc of sterile normal saline into urinary catheter via the sampling port (Larger vol. of NS can result in falsely elevated IAP measurements) • Briefly release the clamp to allow fluid from the bladder to fill tubing and reclaim • Read the IAP as a mean pressure at end expiration 30 – 60 seconds after instillation. • Perform with patient supine • Notify MD for sustained IAP greater than 12 mmHg unless otherwise ordered.

37. Disadvantages with open, intermittent monitoring • Collecting a number of items • Correct assembly • Risk of infection every time system is accessed

38. Closed Monitoring • AbViser, Wolfe Tory Medical, SLC, UT • Pre-assembled kit • Adapts to Foley catheter and any transducer • Reduces risk of infection • Readily available, easily assessable data

40. Measuring Bladder Pressure • Position patient flat & supine • Read Mean pressure • End Expiration

41. Management Considerations Early detection via frequent monitoring of at risk patients Screen for IAH/ACS in new ICU admissions with new or progressive organ failure Look for trends of increasing abdominal pressures Preserve organ perfusion and treat clinical conditions with grades I & II

42. Management Considerations Early surgical consultations for at risk patients Early intervention for ACS or Grade III Anticipate emergent surgical interventions to prevent tissue damage/death

43. Management Considerations • Anticipate patient to return with an alternative surgical closure or “open” abdomen. • The abdominal contents will not be sutured into the abdominal cavity • Alternative closures vary from surgeon to surgeon Examples: The “Bogata Bag” – A 3 L IV bag, open and sterilized and applied to the abdominal opening

45. Management Considerations • KCI Vac Pac • Sponge overlies abd. Dressing/contents • Attached to continuous suction canister • Covered over with occlusive dressing

46. Management Considerations • Ioban Dressing • An occlusive dressing with iodine impregnation • Surgical towels will overlie abdominal contents with JP drains – Ioban overlies abdomen

47. Another Excellent Reference, IAH/ACS Management Algorithm from WSACS www.wsacs.org

48. Conclusion • Know the difference between IAH and ACS • IAH = Abdominal pressure >12 and graded via severity • ACS = Abdominal pressures > 20 – 25 Identify At risk patient populations abdominal trauma/major burns Pancreatitis Ruptured AAA abdominal obstructions/ischemia ect….

49. Conclusion • Understand the pathophysiology • Ischemia/inflammation – inflammatory response – capillary leak + fluid resuscitation = tissue edema in an uncompromising cavity = ACS = tissue/cell death = bad Perform an accurate assessment of abdominal pressure using Abdominal bladder pressure monitoring via Foley catheter or AbViser – Wolfe Torey Medical Anticipate patient interventions/outcomes Support/educate family

50. Case Study - 63 Y.O. male pt with pancreatitis is admitted to the ICU. Pt has history of gallbladder disease, COPD and ETOH abuse. He has been without ETOH reportedly for approximately 24 hrs. VS upon admission are T 38.0, HR 130, BP 90/62, MAP 61, RR 30 – 34 & O2 sat of 91% on 100% NRB, wt approximately 125 kg. His breathing is labored and he has c/o SOB. He is also mildly agitated & resistive to O2 therapy with Bi-Pap. His lung sounds are diminished bilaterally. Denies recent increase in cough. His abdomen is firm and distended. States unknown last BM but + for N/V.