Intra-abdominal Pressure Monitoring Clinical Background HOLTECH MEDICAL Intra-abdominal Pressure Monitoring Clinical Background 24. november 2017 www.holtech-medical.com

www.WSACS.org Definitions Normal range: IAP<10-12 mmHg Intra-abdominal Hypertension = IAH IAH = IAP > 12 mmHg ACS = IAP > 20 mmHg+1 new organ failure APP (abdominal perfusion pressure) = MAP – IAP (same concept as CPP) 24. november 2017 www.holtech-medical.com

Why monitor IAP? IAH occurs  in more than 50% of all surgical and medical ICU patients (ref. 1) IAH adversely affects venous return and microcirculation IAH is associated with significantly increased morbidity and mortality (ref. 2) IAH adversely affects all organs and promotes MOF (ref. 3) IAH causes a covert elevation of CVP, PAOP, ICP (ref. 4) Ref. 1: Manu Malbrain et al: Prevalence of intra-abdominal hypertension in critically ill patients: A multicentre epidemiological study. ICM 2004, 30: 822-9. Ref. 2: Manu LNG Malbrain et al: Incidence and prognosis of Intraabdominal hypertension in a mixed population of critically ill patients: A multicentre epidemiological study. CCM 2005 Vol. 33, No. 2. Ref. 3: Manu LNG Malbrain: Is it wise not to think about intraabdominal hypertension in the ICU? Curr Opin Crit Care 2004; 10:132-145. Ref. 4: Cheatham ML et al: Preload assessment in patients with an open abdomen. J Trauma 1999; 46: 16-22. 24. november 2017 www.holtech-medical.com

CENTRAL NERVOUS SYSTEM CARDIOVASCULAR SYSTEM GASTRO-INTESTINAL SYSTEM Pathophysiology CENTRAL NERVOUS SYSTEM Intracranial pressure  Cerebral perfusion pressure Idiopathic intracranial hypertension (obesity) CARDIOVASCULAR SYSTEM Difficult preload assessment Wedge pressure  Central venous pressure  Intra thoracic blood volume index = Extra vascular lung water = Right ventricular end-diastolic volume index = Cardiac output  Venous return  Systemic vascular resistance  Venous thrombosis  Pulmonary embolism  Heart rate  = Mean arterial pressure  = Pulmonary artery pressure  RESPIRATORY SYSTEM Intrathoracic pressure  Pleural pressure  Functional residual capacity  All lung volumes  (~restrictive disease) Auto-PEEP  ? Peak airway pressure  Plateau pressures  Dynamic compliance  Static compliance  Chest wall compliance  Hypercarbia  PaO2  PaO2/FiO2  Dead-space ventilation  Intrapulmonary shunt  Lower inflection point  Upper inflection point  Prolonged ventilation ? Difficult weaning ? RENAL SYSTEM Renal blood flow  Diuresis  Tubular dysfunction  Glomerular filtration rate  Renal vascular resistance  Renal vein compression  Compression ureters  Anti-diuretic hormone  Adrenal blood flow = GASTRO-INTESTINAL SYSTEM Celiac blood flow  Superior mesenteric artery blood flow  Blood flow to intra-abdominal organs  Mucosal blood flow  Mesenteric vein compression  Intramucosal pH  Regional CO2  CO2-gap  Success enteral feeding  ? Intestinal permeability  Bacterial translocation  ? Multiple organ failure  ? Gastro-intestinal (re)bleeding  HEPATIC SYSTEM Hepatic arterial flow  Portal venous blood flow  Portocollateral flow  Lactate clearance  Glucose metabolism  Mitochondrial function  Cytochrome p450 function  ABDOMINAL WALL Compliance  Rectus sheath blood flow  Wound complications  Incisional hernia  24. november 2017 www.holtech-medical.com Malbrain. Current Opinion Crit Care 2004; 10(2): 132-145

IAP affects blood pressure IAP affects all blood pressures CVP increases by 3-6mmHg when IAP increases by 10mmHg. An example: IAP=10mmHg, CVP=10mmHg. A sudden increase of IAP to 20mmHg changes CVP to 15mmHg. Now, what’s the correct CVP? PAOP, ICP, and lung pressures are also affected by IAP. Correct interpretation of pressures is supported by IAP monitoring 24. november 2017 www.holtech-medical.com

IAH prevalence in 13 EU ICUs Cut-Off Total (n=97) Medical (n=57) Surgery (n=40) IAPmax>= 12 mmHg 57(58.8%) 31(54.4%) 26(65%) IAPmax>= 15 mmHg 28(28.9%) 17(29.8%) 11(27.5%) IAPmax>=20 mmHg 8(8.2%) 6(10.5%) 2(5%) IAPmean>=12 mmHg 23(23.7%) 14(24.6%) 9(22.5%) IAPmean>=15 mmHg 9(9.3%) 7(12.3%) IAPmean>=20 mmHg 4(4.1%) 2(3.5%) Malbrain. Intensive Care Med. 2004 DOI 10.1007/s00134004-2169-9 (online first) 24. november 2017 www.holtech-medical.com

265 pts in 14 ICUs in EU 24. november 2017 www.holtech-medical.com 28-day Mortality: 23% 38% 24. november 2017 www.holtech-medical.com

Indications for IAP monitoring Postoperative (abdom. Surgery) pts Pts with abdominal trauma Ventilated pts with other Organ Failure Pts with signs of ACS: Oliguria, hypoxia, hypotension, acidosis, mesenteric ischemia, ileus, elevated ICP. Pts with high cumulative fluid balance Pts with abdominal packing 24. november 2017 www.holtech-medical.com

Which IAP measurement interval? IAH may develop rapidly Monitor the trend: rising IAP or sustained IAH poor prognosis Recommendation: Measure IAP at each Urine Output determination 24. november 2017 www.holtech-medical.com

IAH treatment options Non-surgical treatment options: WSACS recommendations Non-surgical treatment options: Paracenthesis Gastric suctioning, enemas Gastro/colon prokinetics Furosemide, with or without albumin CVVH with aggressive ultrafiltration Sedation or curarisation Surgical: Decompression 24. november 2017 www.holtech-medical.com

WSACS’ protocol 24. november 2017 www.holtech-medical.com

University of Utah: IAP monitoring algorithm Entry criteria defined in table Nurse is empowered to enter any patient fulfilling these criteria 24. november 2017 www.holtech-medical.com

University of Utah: IAP Monitoring Protocol IAP monitoring Q1-2 hours for first 12 hours IAP consistently <12 mm Hg IAP 12 to 15 mm Hg IAP 15-20 mm Hg with no evidence of organ dysfunction/ ischemia (ACS) IAP >20 mm Hg OR APP< 50-60 mm Hg? Plus evidence of organ dysfunction/ ischemia (ACS) Optimize Abdominal perfusion pressure Careful fluid management Pressors Reduce IAP measurements to Q4-6 hours for 24 hours Consider Medical Management Sedation/Neuromuscular blockade Paracentesis of free fluid Other options Gastric suction, cathartics Rectal tube/enemas Continuous filtration Colloids Surgical Decompression “Second Hit” pt. develops new indication for IAP monitoring IAP remains <12 mm Hg discontinue monitoring 24. november 2017 www.holtech-medical.com

Why monitor IAP rather than ACS Monitoring IAP and normalizing IAH may prevent ACS from happening. It´s like having a SMOKE DETECTOR in your home: It gives you time to locate the smoke (IAH) and cure the problem before the house catches fire (ACS) 24. november 2017 www.holtech-medical.com

How to measure IAP? Patient position: Supine Bladder must be empty Always use same 0 mmHg reference = symph. pubis, or mid-axillary line. 24. november 2017 www.holtech-medical.com

The easy way: 24. november 2017 www.holtech-medical.com 40 mmHg 1. Urine drainage: The urine fills the FoleyManometer and flows on to the urine collection device Pves Mid-ax line = 0mmHg 2. Measure intra-vesical pressure: The urine in the vertical manometer tube returns to the bladder when the vent clamp is opened. Hold the “0 mmHg” mark of the manometer at the midaxillary line/iliac crest, and read Pvesical at the position of the meniscus 24. november 2017 www.holtech-medical.com

Find more information World Society on ACS www.wsacs.org Complete reference list Consensus definitions IAP discussion list Links www.holtech-medical.com Product information Clinical issues Key references 24. november 2017 www.holtech-medical.com