PACT module���Abdominal Problems

Intensive Care Training Program Radboud University Medical Centre Nijmegen

Definition • Normal abdominal pressure 5 - 7 mm Hg

•  Intra-abdominal hypertension

•  Sustained IA pressure ≥ 12 mm Hg

•  Grade 1: 12-15, Grade 2: 16-20, Grade 3: 21-25, Grade 4: > 25

•  Abdominal compartment syndrome

•  IA pressure > 20 mm Hg associated with new organ failure

Definition •  Primary: associated with disease/injury in

the abdominopelvic region and frequently requires surgery/radiological intervention

•  Secondary: without disease in abdomino- pelvic region

•  Recurrent: redevelops after previous medical or surgical therapy for primary or secondary ACS

Point prevalence

IAH = 58.8% ACS = 8.2% N = 97

Maximal IAP (mm Hg) Organ failure

Abdominal compliance

Pressure

Volume

Normal

Abdominal wall compliance decrease

due to hematoma muscle activity, edema

“Supranormal” fluid resuscitation and IAH

DO2 > 600

(N = 85) DO

2 > 500

(N = 71)

Intra-abdominal hypertension 42 20

Abdominal compartment syndrome 16 8

Multiple organ failure 22 9

Death 27 11

Abdominal compartment syndrome without IA injury

•  Excessive fluid resuscitation

•  PEEP

Kf increase intestines

Starling’s law of ultrafiltration: FM = K[Pc + πi) - (Pi + πc)]

where FM = fluid movement, K = filtration coefficient of the capillary wall, Pc = hydrostatic pressure in the capillary, Pi =

hydrostatic pressure in the interstitial fluid, πc = oncotic pressure in the plasma (capillary), and πi = oncotic pressure

in the interstitial fluid.

Physical examination and IAH

Sensitivity 56%

Specificity 87%

PPV 35%

NPV 94%

Accuracy 84%

IAP > 15 mm Hg

Measurement

•  Transvesical - end expiration - supine

•  Continuous - zero at midaxillary line

•  Installation volume 25 ml

• Not with intrapelvic mass

• Measure abdominal perfusion pressure (MAP - IAP) which should be > 60 mm Hg

Abdominal compartment syndrome

mm

Hg

and

cm H

2O

350 200 400 Tidal volume

Decompression

Abdominal compartment syndrome

mm

Hg

Decompression

7.2 3.8 8.4 Cardiac output Lactate 2.1 12 4.6

Diuresis 220 20 200

Abdominal compartment syndrome (IAP 30 mmHG)

Abdominal compartment syndrome

CO

(m

l/min

/kg)

R = 0.86

Abdominal compartment syndrome

Ischemia Reperfusion

Decompressie

Second hit

Volume therapy and threatening ACS

ACS Non-ACS

Packed cells 11 ± 2 2 ± 0.2

Cristalloids (l) 13 ± 2 4.2 ± 0.3

PCWP (mm Hg) 20 ± 1.5 15 ± 0.5

Cardiac Index (l/min/m2) 3.2 ± 0.2 4.2 ± 0.1

PgCO2 (mm Hg) 70 ± 7 48 ± 1

Intra-abdominal hypertension and ICP

mm

Hg

Decompression

Intra-abdominal hypertension and neurotrauma

** ** ** **

mm

Hg

Treatment

• Non-surgical

‣  Evacuate intraluminal contents

‣  Evacuate extraluminal contents

‣  Sedation and neuromuscular blockers

‣  Correction of positive fluid balance

Treatment

1. Improvement of abdominal wall compliance: Sedation, Neuromuscular blockade

2. Evacuation of intra-luminal contents: Gastric tube and suctioning Gastroprokinetics (erythromycin, metoclopramide) Rectal tube and enemas

Colonoprokinetics (neostigmine, prostygmine) Endoscopic decompression of large bowel

3.  Evacuation of peri-intestinal and abdominal fluids: Ascites evacuation Percutaneous drainage of collections

5.  Correction of capillary leak and positive fluid balance: Albumin in combination with diuretics Dialysis or ultrafiltration ���You must first obtain source control then you can try to get rid of the excess fluids by albumin (see SAFE study results, reference below, showing a more positive fluid balance in the saline group and showing a trend towards better outcomes in septic patients 30% vs 35%, p=0.09)

5. Specific therapeutic interventions: Continuous negative abdominal pressure (CNAP)

Negative external abdominal pressure (NEXAP) Targeted abdominal perfusion pressure (APP)

Open abdomen

•  Extensive fluid loss

•  Infection

•  Enterocutaneous fistulae

•  Ventral hernia

•  Cosmetic dysfunction

Open abdomen

• With pressure > 20 and progressive organ failure despite conservative measures

•  Temporary abdominal closure

‣  Bogota bag

‣  Zipper-Wittman patch

‣  Vacuum-assisted closure

Therapy

•  Based on IAP + clinical signs

• No rigid scheme

Grade Pressure (mm Hg) Therapy

Grade 1 10 - 15 Normovolemia

Grade 2 16 - 25 Hypervolemia

Grade 3 26 - 35 Decompression

Grade 4 > 35 Decompression + exploration