ABDOMINAL COMPARTMENT SYNDROMEDR. F MOSAIREGISTRAR: GEN SURGERYMEDUNSA

ACSOUTLINE

1. DEFINATIONS: IAH, ACS2. RISK FACTORS3. AETIOLGY4. PATHOPHYSIOLOGY5. DIAGNOSIS6. TECHNIQUES OF MASURING IAP7. PREVENTION OF ACS8. MANAGEMENT9. COMPLICATIONS OF ASSOCIATED WITH Mx

1. DEFINATIONS

IAH: sustained or repeated pathological increase in IAP= 12mmHg or more

[PAEDS:] IAH: sustained or repeated pathological increase in IAP=10mmHg or more

ACS: sustained IAP=20mmHg or more(with or without an APP<60mmHg) that is associated with new organ dysfunction/failure

[PEADS] ACS: sustained increased IAP >10mmHg ass with new or worsening organ dysfx that can be attributed to increase in IAP

2. RISK FACTORS

Diminished abdominal wall compliance Major burns, abd surgery, major trauma, prone position

Increased intraluminal contents Volvulus, gastric distension, gastroparesis, Ileus, colonic

pseudo-obstruction Increased Intra-abdominal contents

Haemoperitonium/pneumoperitonium or intra-peritoneal fluid collection,tumours

2. RISK FACTORS

Capillary leak/fluid resuscitation Massive fluid resuscitation or positive fluid balance, damage

control laparotomy, hypothermia Others/miscellaneous

Mechanical ventilation, increase BMI, sepsis, shock,coagulopathy

3. AETIOLOGY

Acute: Retroperitoneal: pancreatitis, bleed, visceral oedema, aortic

aneurism Intraperitoneal: bleed, bowel obstruction, ileus, oedema,

gastric dilatation Abdominal wall: burn eschar, repair of gastroschisis or

omphalocele, reduction of large hernias, laparotomy closure under tension

Chronic: Obesity,ascitis, intra-abd tumors, preganancy, peritoneal

dialysis

4. PATHOPHYSIOLOGY

CNS: ↓ venous outflow ↑ ICP ->cerebral oedema-> ↓ CPP

CVS: ↑ systemic vascular resistance due to compression at the level of the capillary bed

:↓ venous return:diaphram displacement→↑ intrathoracic pressure→↓ventricular compliance→↓ CO + SV

4. PATHOPHYSIOLOGY

Resp: ↑diaphram →↓ pulmonary compliance

:↓TLC , ↓FRC, ↓RV : V/Q abnormal and hypoventilation→ hypoxia and hypercarbia

ABD:↓ flow in mesenteric, intestinal, hepatic and portal venous flow→ ischaemia and ↑risk of translocation

4. PATHOPHYSIOLOGY

Renal:↑IAP→ obstruct renal outflow +renal arteries :↑ ADH, renin and aldosterone→ ↑vascular resistance, Na + H2O

5. DAIGNOSIS

Hx: ↓urine output with ↑CVP ↑ Peak airway pressure Massive volume resuscitation Damage control laparotomy shock

5. DAIGNOSISCRITERIA FOR Dx1. IAP >25mmHg (30cmH₂O)AND2. One or more of the following

Oligouria (0.5ml/kg/h) ↑pulmonary pressure (>45cmH₂O) Hypoxia ↓CO Hypotension Acidosis

AND(to comfirm Dx)

5. DAIGNOSIS

3. Abdominal decompression lead to clinical improvement

6. TECHNIQUE TO MEASURE IAP

Sterile procedure Supine position, Θ abd muscle contraction Transducer, zero at the level of midaxillary line Place a special catheter and empty bladder Clamp catheter and instill ≤25ml sterile saline into

bladder and wait 30sec for detrusor muscle relaxation before measuring pressure

Measure at end expiration at the phlebostatic axis [Peads: instill 1ml/kg, min:3ml-max:25ml)

7. PREVENTION OF ACS

Prophylactic use of open abdomen after trauma damage control laparotomy

Damage control resuscitation Limitation of crystalloid fluids ↑ratio of plasma/packed red blood cell for resuscitation of

massive haemorrhage Keep fluid balance neutral or even negative Body positioning(trendelenberg)

8. MANAGEMENT

1. Non-operative(MEDICAL) Indications:

IAH Secondary or recurrent ACS with no progressive organ

failure2. Operative Indications:

Primary ACS/ overt ACS Secondary or recurrent ACS with progressive organ failure IAH( failed non-operative Rx)

8. MANAGEMENT

1. Non-operative Mx Improve abdominal wall compliance

Sedation and analgesia Paralysis(neuromascular blockade) Trendelenberg position( avoid head of bed >30°)

Evacuate intraluminal contents NG-decompresion Rectal/colonic decompression Gastro/colo-prokinetics(e.g. Neostigmine)

8. MANAGEMENT

Evacuate abdominal fluid collection PCD(abscess, haematoma) Paracentesis(not recommended)

Correct positive fluid balance Avoid excessive fluid resuscitation Diuretics(NOT RECOMMENDED) Colloid or hypertonic fluids Albumin (NOT RECOMMENDED) Hemodialysis/ultrafiltration(NOT RECOMMENDED)

8. MANAGEMENT

Damage control resuscitation Limit crystalloid iv fluid ↑plasma/packed red blood cell ratio for massive

hemorrhage

8. MANAGEMENT

2. Operative Acute decompresive laparotomy Wound cover after laparotomy

Silo Bag closure 3l Bogota bag (with closed suction to control fluid exudate)

Sandwish and vacuum pack technique NPWT(negative pressure wound therapy) Bioprosthetic mesh closure(NOT RECOMMENDED FOR

ROUTINE USE)

9. COMPLICATIONS

Intraoperative Surgical related

Sudden release of IAP lead to reperfusion injury, SIRS, Acidosis, hyperkalemia and ↑myglobin

Rx: consider: 1l 0.45% saline with 50g Mannitol and 50mmol sodiun bicarbonate

Anaesthetic related Aspiration (↑IAP)

9. COMPLICATIONS

Post-operative Short term(due to prolong open abdomen)

Visceral adhessions Loss of soft tissue coverage Lateralization of the abdominal musculature and its fascia Malnutrion Enteric fistulae

Long term Incisional hernia Adhessive bowel obstruction