UPMC Critical Care

www.ccm.pitt.edu  Exemplary Care  Cutting-edge Research  World-class Education  and

Samuel A. Tisherman, MD, FACS, FCCM Professor Departments of CCM and University of Pittsburgh

 Exemplary Care  Cutting-edge Research  World-class Education  Shock

Anaerobic metabolism Lactic acidosis

“Dysoxia” Activation of inflammatory cascades

Inadequate DO 2 Organ system dysfunction

 Exemplary Care  Cutting-edge Research  World-class Education  Shock Normal cardiovascular system

Pathophysiology of shock

Categories of shock

Resuscitation

Monitoring

 Exemplary Care  Cutting-edge Research  World-class Education  Key components of CV system Intravascular volume Preload rate Contractility

 Exemplary Care  Cutting-edge Research  World-class Education  Key components of CV system Resistance circuit – arterioles Distribution of organ flow

Capillaries Leak Obstruction to flow Shunts

Venous capacitance vessels Vary venous return

 Exemplary Care  Cutting-edge Research  World-class Education  Organ blood flow Most dependent upon mean arterial pressure (MAP)

Autoregulation Maintained during large variations of MAP 60-130 mmHg Can be impaired -

 Exemplary Care  Cutting-edge Research  World-class Education  Autoregulation

 Exemplary Care  Cutting-edge Research  World-class Education  Supply and demand

O2 delivery O2 demand Hemoglobin Saturation Cardiac output

20-60%

VO2 = DO2 x ERO2

ER = extraction ratio

 Exemplary Care  Cutting-edge Research  World-class Education  O2 supply dependency

Critical Critical Dysoxia DO2 DO2

Oxygen consumption Lactic acidosis

Oxygen delivery

 Exemplary Care  Cutting-edge Research  World-class Education  Cytopathic Normal oxygen delivery

Impaired mitochondrial O2 utilization Mediators Inflammatory cytokines Inhibition of pyruvate dehydrogenase Inhibition of cytochrome a,a3 by NO Irreversible inhibition of one or more mitochondrial respiratory complexes by peroxynitrite Poly(ADP-ribose) polymerase-1

 Exemplary Care  Cutting-edge Research  World-class Education  Reperfusion Injury

Xanthine ATP Dehydrogenase Ischemia Hypoxanthine Xanthine Oxidase

Reperfusion O2

Oxygen radical formation Lipid mediator release

Endothelial cell dysfunction Neutrophil chemotaxis Microvascular changes

Tissue injury It’s not the fall that gets you….

 Exemplary Care  Cutting-edge Research  World-class Education  Organ failure

Ischemic Injury Reperfusion injury Organ Damage

Inflammatory mediators (TNF, NO, free radicals)

 Exemplary Care  Cutting-edge Research  World-class Education  Classifications of shock

Hypotension Hypodynamic Hyperdynamic Low CO (narrow PP) Low SVR (wide PP) ? Sepsis No Yes JVD? Liver failure No Yes Cardiogenic shock Medications RV failure MI Hemorrhage Obstructive Valvular dz Dehydration PE Tamponade PTX

 Exemplary Care  Cutting-edge Research  World-class Education  Hemorrhagic shock Most common cause of in trauma patients Initial fluid should be crystalloid Transfusion Hypotensive after 2 L crystalloid (ATLS) Earlier for severe shock Uncontrolled hemorrhage Stop hemorrhage Limited fluid

 Exemplary Care  Cutting-edge Research  World-class Education  Cardiogenic shock Resuscitation simultaneous with

Patients may need higher than normal filling pressures (poor LV compliance)

Inotropes may worsen ischemia

Pacing may be helpful for relative

Intra-aortic balloon pump improves coronary and decreases afterload

 Exemplary Care  Cutting-edge Research  World-class Education  Risk factors Hypercoagulability, stasis, trauma Presentation Respiratory Cardiovascular Diagnosis CT angio, VQ, echo, angio, d-dimer Management Anticoagulation, thrombolytic, embolectomy Prevent the next one -?filter

 Exemplary Care  Cutting-edge Research  World-class Education  Pentrating trauma more common than blunt Beck’s triad (hypotension, distant , JVD) obscured by hypovolemia High index of suspicion Diagnose: echo or pericardial window Treatment: Need sternotomy or thoracotomy (trauma) Pericardiocentesis (non-trauma)

 Exemplary Care  Cutting-edge Research  World-class Education  Decreased preload Hypovolemia (capillary leak) Increased venous capacitance Vasodilatation Cardiac dysfunction Ventricular dilatation Decreased ejection fraction Cytopathic hypoxia

 Exemplary Care  Cutting-edge Research  World-class Education  Endstage shock

CardiacIrreversible shockVasomotor decompensationTerminal hypodynamicdysfunction state

 Exemplary Care  Cutting-edge Research  World-class Education  Initial management

 Exemplary Care  Cutting-edge Research  World-class Education  Initial management Resuscitation Definitive therapy Ventilation Stop ?intubation early Circulatory assist Infusion and Bolus to effect drainage/debridement ?blood Clear lactate Pump therapy Inotropic support Afterload reduction Vasodilatation Vasopressor support

 Exemplary Care  Cutting-edge Research  World-class Education  Monitoring

 Exemplary Care  Cutting-edge Research  World-class Education  CVP Only elevated in disease RV dysfunction Pulmonary hypertension LV dysfunction Tamponade Hyperinflation Intravascular volume expansion

Poor correlation with volume responsiveness

 Exemplary Care  Cutting-edge Research  World-class Education  PAOP and Preload

Muscle

LVEDV

LVEDP

LAP

PAOP

 Exemplary Care  Cutting-edge Research  World-class Education  CVP and PAOP

Kumar, et al. CCM, 2004.  Exemplary Care  Cutting-edge Research  World-class Education  Functional Hemodynamic Monitoring

2-3 heart beats later

 Exemplary Care  Cutting-edge Research  World-class Education  Resp variation in pressure

Limitations: spontaneous breathing, . Michard and Teboul. Crit care, 2000.  Exemplary Care  Cutting-edge Research  World-class Education  Passive Leg Raising

 Exemplary Care  Cutting-edge Research  World-class Education  Passive Leg Raising

Monnet, et al. CCM, 2012.  Exemplary Care  Cutting-edge Research  World-class Education  Preload Echo Distensibility index

Max-min DIVC x 100% Min DIVC Collapsibility index

Max-min DIVC x 100% Max DIVC Resp variability index

ΔDIVC = Max-min DIVC x 100% Mean DIVC

Feissel, et al. Intensive Care Med, 2004.

 Exemplary Care  Cutting-edge Research  World-class Education  Mixed venous oxygen - SvO2

Decrease SvO2 Decrease DO2 Hb, O2 sat, cardiac output Increase O2 demands Fever, sepsis, exercise Normal >65% Critical value ~40% Resuscitation endpoint for sepsis and cardiogenic shock Sepsis -> maldistribution of blood flow SvO2 normal with tissue dysoxia still present

 Exemplary Care  Cutting-edge Research  World-class Education  Oxidative Metabolism

Glucose 2 ATP Pyruvate Lactate

Mitochondria Acetyl CoA

2 ATP Citric acid Cycle Remember 2:38 NADH/FADH2 Electron transport chain

O2 H2O ADP 34 ATP

 Exemplary Care  Cutting-edge Research  World-class Education  Base Deficit Definition

Amount of base needed to normalize pH with normal PCO2 Limitations Administration of bicarbonate Alcohol intoxication Hyperchloremic metabolic acidosis Seizures Pre-existing acidosis

 Exemplary Care  Cutting-edge Research  World-class Education  Lactate Excess production Anaerobic metabolism Initial level and time to clearance useful Decreased metabolism (liver, kidney) Washout during reperfusion Sepsis Increase flux of alanine from muscle Decreased PDH activity Decreased hepatic clearance Dysfunctional mitochondrial respiration

 Exemplary Care  Cutting-edge Research  World-class Education  Near Infrared Spectroscopy

Measurements Location PO2 Muscle PCO2 Stomach pH Bowel O saturation of hemoglobin 2 Liver Tissue oxyhemoglobin coupling to cytochrome a,a3 redox

Mitochondrial O2

 Exemplary Care  Cutting-edge Research  World-class Education 

Hypotension Hypodynamic Hyperdynamic Low CO (narrow PP) Low SVR (wide PP) Pulmonary edema? Distributive shock Sepsis No Yes Neurogenic shock JVD? Adrenal insufficiency Liver failure No Yes Anaphylaxis Cardiogenic shock Medications Hypovolemia RV failure MI Hemorrhage Obstructive Valvular dz Dehydration PE Tamponade PTX Fluids Fluids Fluids Vasopressors Blood Inotropes IABP EGDTx Hemostasis Specific Tx Revascularize Treat cause

Base deficit SvO Lactate 2 UPMC Critical Care

www.ccm.pitt.edu  Exemplary Care  Cutting-edge Research  World-class Education 