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ACS and Critical Care: Optimising Ventilation CLAUDIA I. OLVERA M.D. ABDOMINAL COMPARTMENT SYNDROME WORLD CONGRESS Noosa, Australia. December 8, 2004 THE AMERICAN BRITISH COWDRAY MEDICAL CENTER I.A.P. MEXICO CITY, MEXICO. OPTIMISING VENTILATION. Contents. 1. Introduction (Incidence)
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ACS and Critical Care: Optimising Ventilation CLAUDIA I. OLVERA M.D. ABDOMINAL COMPARTMENT SYNDROME WORLD CONGRESS Noosa, Australia. December 8, 2004 THE AMERICAN BRITISH COWDRAY MEDICAL CENTER I.A.P. MEXICO CITY, MEXICO
OPTIMISING VENTILATION Contents 1. Introduction (Incidence) 2. Physiological Effects of IAP (Spontaneous vs. Mechanical Ventilation) 3. Respiratory Dysfunction 4. Effects of IAP on FRC 5. IAP and ALI / ARDS (Type) 6. Lung Response to Decompression 7. NIMV 8. Management
OPTIMISING VENTILATION Introduction 100,000 positive pressure ventilators in use worldwide USA 1.5-2.5 million patients receive MV outside the OR / Recovery room per yr Acute care setting – average length of MV is 6-8 days MacIntyre NR. Mechanical Ventilation – The next 50 years. Respir Care 1998;43:490-3
OPTIMISING VENTILATION Incidence Malbrain: 53 pt in medical ICU: 24% (8.4mmHg) Malbrain 405 mixed ICU: General incidence: 17.5% (15.8mmHg) Surgical pt.: 39.4% Medical pt.: 19.8% Elective surgery: 6.1% Malbrain M. Crit Care Med 1999;27(1S)36A
OPTIMISING VENTILATION Physiological Effects of Increased IAP CENTRAL NERVOUS SYSTEM > ICP < CPP CARDIAC < C.O. < VENOUS RETURN > SVR PULMONARY INTRATHORACIC PRESSURE PIP PAW Cdyn PaO2 PaCO2 HEPATIC < PORTAL BLOOD FLOW GASTROINTESTINAL < MUCOSAL BLOOD FLOW < pHi RENAL < URINARY OUTPUT < GFR
OPTIMISING VENTILATION Spontaneous vs. Mech. Ventilation . Q PA Insp. VL VD Ppl PAo PLA TM PPA TM PRA TM Ppl PAW PRA Biondi JW et al. Effects of Mech Vent on Right and left Ventr Funct En: Clin Chest Med. Mech Vent. (Morganroth L ed.) Phi, Saunders 1988.
OPTIMISING VENTILATION Physiological Effects of Increased IAP Normal movement of the lungs Courtesy of Dr. Paolo Pelosi
OPTIMISING VENTILATION Physiological Effects of Increased IAP IAH Courtesy of Dr. Paolo Pelosi
OPTIMISING VENTILATION Physiological Effects of Increased IAP Abdominal Abdominal pressure pressure Effects of IAP on: Lung distension and recruitment Pulmonary edema
OPTIMISING VENTILATION Respiratory dysfunction diaphragm; of lung volumes and compliance Acute restrictive pattern ( of TLC) ~ PaCO2 PIP, Pplateau, PVR V/Q mismatch (PaO2 , shunts) Atelectasis, slow progression of MV and of WOB PEEP???? Meldrum. Am J Surg 1995;170:537-42Malbrain. Curr Opin Crit Care 2000;6:17-29
OPTIMISING VENTILATION Pulmonary physiology leading to ARF IRV VC VT ERV FRC RV NORMAL TYPE A TYPE B TYPE C Pulmonary pathophysiology leading to acute respiratory failure.In: Clinical Application of Respiratory Care (Shapiro B, Harrison RA andTrout CA. Eds). Year Book Medical Publishers, Inc. Chicago 1979: 311-7
OPTIMISING VENTILATION Effects of IAP on FRC FRC FRC (Resting lung volume, ml) Intra-Abdominal pressure (cmH2O) IAP Abdominal balloon volume (ml) Mutoh T, Lamm WJE, Embree LJ, et al. J. Appl. Physiol. 1991;70 (6):2611-8
OPTIMISING VENTILATION Physiological effects of IAP Control TLC IAP Pdi Pab Lung TLC Lung volume (% control TLC) FRC Chest wall FRC RV RV Mean distending pressure (cmH2O) Pressure (cmH2O) Airway Pressure (cmH2O) Mutoh T, Lamm WJE, Embree LJ, et al. J. Appl. Physiol. 1991;70 (6):2611-8
OPTIMISING VENTILATION IAP and Acute Lung Injury 50 0 10 20 30 40 0 10 20 30 40 50 10 20 30 40 -10 0 7 pigs Oleic Acid 0 cmH2O Intra-Abdominal Pressure 20 cmH2O Intra-Abdominal Pressure Whole respiratory system Lung Chest wall 2 Volume (L) 1 Pressure (cmH2O) Quintel M, et al. Am J Respir Crit Care Med 2004;169:534-41
OPTIMISING VENTILATION IAP and Acute Lung Injury Oleic acid pig Recruitment model Paw [cmH2O] 0 20 40 0 I.A.P. (cmH2O) 20 Quintel M, et al. Am J Respir Crit Care Med 2004;169:534-41
OPTIMISING VENTILATION IAP and Acute Lung Injury Injured Healthy 0 I.A.P. (cmH2O) 20 Quintel M, et al. Am J Respir Crit Care Med 2004;169:534-41
OPTIMISING VENTILATION IAP and Acute Lung Injury Gas volume Total, gas and tissue volumes 1400 Tissue volume 1200 1000 800 Volume (ml) 600 400 200 0 Normal Oleic Acid (cmH2O) IAP 0 IAP 20 IAP 0 IAP 20 Quintel M, et al. Am J Respir Crit Care Med 2004;169:534-41
OPTIMISING VENTILATION IAP and Acute Lung Injury * ° ° IAP 0 IAP 20 100 75 Shunt % 50 * 25 0 Oleic Acid Normal *p < 0.05 vs IAP 0 °p < 0.05 vs Normal Quintel M, et al. Am J Respir Crit Care Med 2004;169:534-41
3.0 2.5 ° * 2.0 * * * * 1.5 * 1.0 0.5 0.0 -0.5 1 2 3 4 5 6 7 8 9 10 OPTIMISING VENTILATION Excess Tissue Mass Injured lungs, end expiration Excess tissue mass (%) Segments (cephalo-caudal gradient) IAP 0 cmH2O IAP 20 cmH2O Quintel M, et al. Am J Respir Crit Care Med 2004;169:534-41
OPTIMISING VENTILATION IAP and type of ARDS 20 18 n = 21 r = 0.83 16 p < 0.0001 14 12 10 Chest-Wall Elastance (cmH2O/L) 8 6 ARDSp 4 ARDSexp 2 0 0 5 10 15 20 25 30 35 40 Intra-Abdominal Pressure [cmH2O] Gattinoni, et al. Am J Respir Crit Care Med 1998;158:3-11
OPTIMISING VENTILATION Physiological effects of IAP Preop. Cardiac surgery ARDSp ARDSexp End Exp. Lung Vol. Mean static inflation volume-pressure curves of the abdomen Ranieri M, et al. Am J Respir Crit Care Med 1997;156:1082-91
OPTIMISING VENTILATION Lung response to IAP & decompression 3 * p < 0.05 2 Neutrophils (x106) 1 0 sham ACS ACS sham ACSd 60 min 90 min MPO levels in the lung as an index of neutrophil infiltration Rezende N, et al. J Trauma 2002;53:1121-8
OPTIMISING VENTILATION Lung response to IAP & decompression atelectasis diffuse hyperemia septal enlargement ACS 60’ Sham MV 60’ mononuclear cells 30’after AD ACS 90’ Alv. macrophages alveolar edema Inflamm. cells (Neu, mon, mast) diffuse atelectasis, alv. edema +> septal enlargement Rezende N, et al. J Trauma 2002;53:1121-8
OPTIMISING VENTILATION Effect of NIMV after AD 100 80 60 FVC (% baseline) 40 NO BIPAP 20 BIPAP 8/4 BIPAP 12/4 0 Preop Day 1 Day 2 Day 3 Joris JL, et al. Chest 1197;111(3):665-70
OPTIMISING VENTILATION Effect of NIMV after AD 100 98 96 94 SpO2 (%) 92 90 NO BIPAP BIPAP 8/4 88 BIPAP 12/4 86 Preop Day 1 Day 2 Day 3 Joris JL, et al. Chest 1197;111(3):665-70
OPTIMISING VENTILATION Physiological effects of decompression Variable Before After p PaO2/FiO2 165±78 236 ± 119 0.03 Qs/Qt (%) 33 ±12 21 ±12 0.04 Cdyn (mL/cmH2O) 13 ±5.0 24 ±6.8 <0.001 Chang, J Trauma, 1998;44:440-5
OPTIMISING VENTILATION Physiological Effects of Decompression A B n-14 IAP • CVP 18.21 10.38 10.78 4.04 p=0.019 • PCP 18.71 8.74 12.43 4.8 p=0.026 • MPAP 39.21 7.93 28.36 7.9 p=0.001 C D IAP IAP ml/cmH20 • Compliance 21.79 6.08 34.57 12.91 p=0.002 • Shunts 47.64 11.81 35.71 8.21 p=0.005 Olvera, Crit Care Med 2000;28(12):A135
OPTIMISING VENTILATION Physiological Effects of Decompression A B n-14 Hyperdynamic Normal Hypodynamic CI CI: from 5.06 1.31 to 4.01 1.17 PIP: from 38.14 6.36 to 26 ± 9.59 C Comparison between IAP before and after abdominal decompression: A) CI (p=0.03) B) PIP (p=0.0001) and C)PaO2/FiO2 (p=0.001) PaO2/FiO2 from 102 47 to 176 ± 59 Olvera, Crit Care Med 2000;28(12):A135
OPTIMISING VENTILATION Management Improvement: Adjust MV to physiologic parameters Spontaneous (NIMV?) PEEP Weaning IAH / ACS Recruitment (VT) Limited PEEP Limited pressures FiO2 ? PEEP as needed FiO2 to non-toxic levels VT as required (CO2) Abdominal decompression Opening lung approach / Lung protective strategies ( PEEP, LTV, limited pressures) ARDS >48 hs Time