Red Book - Abdominal Compartment Syndrome Flashcards
Normal IAP
5-7 mmHg
Define Abdominal Perfusion Pressure
APP = MAP - IAP
Define Intra-abdominal hypertension
IAH - sustained or repeated pathologival elevation in IAP above 12 mmHg
Define Abdocompartment syndrome
Sustaned IAP >20mmHg
with or without APP<60mmHg
associated with NEW organ dysfunction
Grading of ACS
1 - 12-15mmHg
2 - 16-20mmHg
3 - 21-25 mmHg
4 > 26mmHg
How to classify ACS
Primary:
Due to pathology of abdomen
Secondary:
Extra-abdominal process
Catergorise the risk factors for ACS:
Diminished wall compliance –> surgery, tight closure, trauma, burns, proned
Increased abdominal contents –> Intra-luminal –> ileus, gastroparesis
extraluminal –> ascites, haemoperitoneum/pneumo
Capillary leak –> sepsis, trauma, burns, pancreatisis
hypothermia, acidosis
massive transfusion
positive fluid balance
Other: mechanical vent, PEEP>10, increased head angle, hypotension
Measure IAP
Direct or indirect
Direct - Needle into abdomen - trochar at laparoscopy
Indirect - Intra-vesicle pressure - urinary bladder catheter
25mls into catheter, attach drainage bag, cross clamp
16g needle to a transducer is attached to culture port site
Resp issues with IAH
Basal atelectasis, collapse, diaphragm splints
Reduced chest wall compliance
V/Q mismatch, hypoxeamia, hypercapnoea
PEEP - worsens venout return and CO
CVS effects of IAH
Raised IAP transmits to vasculature
Reduced CO –> reduced venous return
Leads to reduced APP
Neuro effects of IAH
Raised ICP as cerebral venous return impeded due to raised thoracic pressure
Hypoxaemia causes cerebral vasodilation and worsens ICP
Renal effects
Direct compression of renal vessels, reduces RBF
Pressure on tubules, reduces filtration gradient
Compensatory activates RAAS - worsening insultin
GI/hepatic IAH
Hypoperfusion and venous hypertension - bowel oedema
Ischaemia and translocation
Reduced hep art. flow
Bilary stasis
Principles of management
ABCDE approach treating specific abnromalities as found:
Principles:
Serial monitoring
Medical:
Improve wall compliance, sedate, paralyse, analgesia, positioning
Fluid - avoid excess resus, consider RRT Evacuate intra-lumen - gastric decompression, laxatives, pro-kinetics Evacutae extra lumen - collections drained, paracentesis Organ support - APP>60 with vasopressors
Surgical - laparotostomy
negative pressure wound dressing
Complications of IAH
Untreated, 100% mortality
Multi organ failure
Define an open abdomen
WCACS Consensus - one that requires a temporary abdominal closure due to skin and fascia not being closed after laparotomy
Why have an open abdo
Traditionally a last resort strategy in abdominal catostrophe where it cant be closed
Preferred now and preventitive in both trauma/non-trauma
Indications for an open abdom
Severe necrotising pancreatitis
Abdominal sepsis
Damage control surgery (trauma)
Emergency vascular surgery
Issues with an open abdomen
Nursing - skin care, wound moisture etc
positioning, turning
pain
Significant fluid loss and unrecordable fluid balance
Malnutrition - source protein/nitrogen loss
Infection
Visceral injury/adhesions
Ileus
Wall - hernias, cannot close, enterocutaneous fistula
Options for temporary closure
1) Bogota bag (3 litre urology irrigation bag)
2) Negative pressure dressings/Vac
3) Synthetic mesh devices
4) Velcro sheath - Whittman pathc
Managing the open abdo on ICU
General:
Nutrition, fluid balacne, nursing care
Resus to normal physiology
Correct hypothermia/coag/acidosis
Lung protective vent
Sedate, analgesia and blockade
(RASS -4)
Enteral feeding if GI working
Add in extra protein 2g/litre of nitrogen lost
Abx
Washouts
Stoma is soiling
