Term
Hypovolemic Shock: Etiology |
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Definition
Reduction in intravascular volume |
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Term
Hypovolemic Shock: Conditions Causing Intravascular Volume Depletion |
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Definition
- Hemorrhagic (GI bleed, trauma, surgery, internal bleeding)
- Non-Hemorrhagic (dehydration, fluid shifting, cutaneous loss)
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Term
Hypovolemic Shock: Hemodynamic Parameters |
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Definition
- Decreased PCWP and Decreased CVP due to decreased venous return (preload)
- Decreased CO due to decreased venous return (decreased SV)
- Compensatory increase in SVR to maintain BP, however often inadequate compensation --> hypotension and hypoperfusion prevail
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Term
Hypovolemic Shock: Management |
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Definition
- Fluid resuscitation
- Correct inadequate tissue perfusion and oxygenation
- CVP > 12 mmHg, CI > 2.2 L/min
- Rapid infusion of IV fluids (crystalloids or colloids) is necessary to restore intravascular volume
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Term
Cardiogenic Shock: Etiology |
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Definition
Abnormality in cardiac function |
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Term
Cardiogenic Shock: Conditions That Precipitate Cardiogenic Shock |
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Definition
- Non-Mechanical (acute MI, acute CHf exacerbation, cardiomyopathy)
- Mechanical (Mitral or aortic valve insufficiency, severe aortic stenosis, septum or free wall rupture)
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Term
Cardiogenic Shock: Hemodynamic Parameters |
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Definition
- Decrease CO due to pump failure
- Compensatory increase SVR to maintain BP
- Increase PCWP or CVP (esp. in CHF) b/c heart cannot pump blood through circulation --> volume overload
- Overall, decrease in arterial BP and hypoperfusion -- can lead to ischemia in various organs
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Term
Cardiogenic Shock: Management |
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Definition
- Selection of agent(s) depends on patient presentation and etiology: Inotropes, diuretics, vasodilators, vasopressors, IV fluids, intra-aortic balloon pump, ventricular assist device
- CI > 2.5, PCWP < 18, MAP > 65
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Term
Distributive (Vasodilatory) Shock: Etiology |
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Definition
Loss of vascular tone leading to hypotension and hypoperfusion |
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Term
Distributive (Vasodilatory) Shock: Conditions Causing Distributive Shock |
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Definition
- Septic shock
- Anaphylaxis
- Neurogenic causes -- spinal injury, cerebral damage, etc.
- Drug-induced -- anesthesia, overdose of opiods, etc.
- Acute adrenal insufficiency
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Term
Definition of Systemic Inflammatory Response Syndromes (SIRS) |
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Definition
Must meet 2 out of the 4 following criteria:
- Temp < 36°C or > 38°C
- HR > 90 beats/min
- RR > 20 RPM or PaCO2 < 32 mmHg
- WBC < 4000 or > 12000 or > 12% bands
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Term
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Definition
SIRS + suspected or documented infection |
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Term
Definition of Severe Sepsis |
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Definition
Sepsis + organ dysfunction, hypoperfusion, or hypotension |
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Term
Definition of Septic Shock |
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Definition
Sepsis + persistent hypotension after adequate fluid resuscitation requiring vasopressor therapy |
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Term
Risk Factors for Severe Sepsis |
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Definition
- All critically ill patients
- Severe Community-Acquired Pneumoniae (CAP)
- Intra-Abdominal Surgery
- Meningitis
- Chronic diseases (DM, HF, Chronic HF, COPD)
- Compromised Immune Status (HIV/AIDS, use of cytotoxic and immunosuppressive agents, malignant neoplasms, alcoholism)
- Cellulitis
- UTIs
- Severe Injuries (bullet wounds, severe burns, etc.)
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Term
Patients at Greater Risk for Severe Sepsis |
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Definition
- Age > 65
- Underlying comorbidities
- Pre-existing organ dysfunction
- Higher body weight
- Medical Treatment with a medical device
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Term
What are the 2 mechanisms (pathophysiology) of sepsis? |
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Definition
1. Inflammation
- In response to an infection, ischemia, or injury -- inflammatory cytokines are produced by the body
- Release of cytokines and other mediators lead to:
↑ capillary permeability (↓ intravascular volume) --> vasodilation of blood vessels (hypoperfusion) and ultimately cellular death and multiple organ failure
- TNF-α is one of the primary mediators of sepsis
2. Coagulation
- Activation of coagulation cascade --> pro-coagulation --> microvascular thrombosis
- Increased Pro-Coagulants:
Thrombin
Plasminogen activator inhibitor
Thrombin activatable fibrinolysis inhibitor
Protein C
Plasminogen
Antithrombin III |
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Term
Signs and Symptoms of Early Sepsis |
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Definition
- Fever/Chills/Myalgias
- Increased/Decreased WBCs: left shift
- Hypoxia (PaO2 < 70%)
- HR > 90
- Hyperventilation (RR > 20, PaCO2 > 30)
- Changes in mental status
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Term
Signs and Symptoms of Severe Sepsis/Septic Shock |
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Definition
- Oliguria/Anuria (UO < 0.5 ml/kg/hr)
- Increased SCr
- Lactic Acidosis (lactic acid > 1.5 ULN)
- Hypotension/Myocardial Depression
- Elevated LFTs
- Disseminated Intravascular Coagulopathy (decreased platelets/decrease fibrinogen)
- ARDS (lung injury)
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Term
Diagnosis of Sepsis/Septic Shock |
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Definition
1. Presumed or known site of infection
- Purulent sputum or respiratory sample
- Chest radiograph with new infiltrates not explained by a noninfectious process
- Spillage of bowel contents noted during operation
- Radiographic or physical examination evidence of an infected collection
- WBCs in normally sterile fluid
- Positive blood culture
- Evidence of infected mechanical hardware by physical or radiographic examination
2. Evidence of SIRS (2 out of 4 criteria)
3. Sepsis-Induced Organ failure
- Cardiovascular dysfunction (MAP < 60 mmHg) - need vasopressors to maintain BP in the face of adequate intravascular volume (CVP > 8-10) or after an adequate fluid challenge has been given
- Respiratory organ failure - respiratory distress requiring mechanical ventilation
- Renal dysfunction - UO < 0.5 ml/kg/hr for 1 hr in the face of adequate intravascular volume or after an adequate fluid challenge
- Hematologic dysfunction - thrombocytopenia or a 50% drop in platelets in the previous 3 days, INR > 1.2 that cannot be explained by liver dz or warfarin usage
- Anion-Gap Metabolic Acidosis - pH < 7.30, plasma lactate > 1.5 x the upper limit of normal
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Term
Goals of Therapy for Early-Goal Directed Therapy |
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Definition
Should be started in the ER, within the initial 6 hrs, and not delayed until patient reaches ICU
- CVP 8-12 mmHg (12-15 if pt on ventilator)
- MAP > 65
- UO > 0.5 ml/kg/hr
- Central Venous O2 saturation (SVO2) > 70% or Mixed Venous O2 Saturation (MVO2) > 65%
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Term
Choice of Fluids for Early Goal Directed Therapy |
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Definition
1. Crystalloids
- Rate of 500-1000 ml q 15-30 min
- Isotonic sol'n -- 0.9% NaCl or LR
- Recommended initially to expand intravascular volume -- cheaper than colloids and more readily available
2. Colloids
- Expand intravascular space for longer duration than crystalloids
- More expensive and more side effects -- higher incidence of renal failure when pts put on hetastarch compared to LR
- May be beneficial in pts w/ low albumin or pts not responding to crystalloids
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Term
Vasopressors for Early Goal Directed Therapy |
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Definition
- First Line Agents: Dopamine or Norepinephrine
- Vasopressors increase MAP
- Initiate if hemodynamic instability (MAP < 65 mmHg) persists despite adequate fluid resuscitation (CVP 8-10 mmHg)
- Refractory hypotension despite high doses of NE -- consider adding vasopressin 0.04 units/min
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Term
Blood Product Administration for Early Goal Directed Therapy |
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Definition
- Indicated if SVO2 < 70% and Hct < 30%
- Transfuse to achieve a Hct of 30%
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Term
Inotropic Therapy for Early Goal Directed Therapy |
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Definition
- First Line Agent: Dobutamine
- Increases CO
- Indicated if SVO2 < 70% and Hct > 30%
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Term
Antibiotic Therapy: Adminstration time, spectrum coverage |
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Definition
- Obtain cultures prior to antibiotc therapy
- Antibiotics should be administered within 1 hr of recognizing the clinical syndrome of sepsis
- Choice of antibiotics should cover MRSA and P. aeruginosa and other G-, G+, and Anaerobic organisms
- Empiric double coverage of Pseudomonas from 2 different classes as well as MRSA coverage
- Choice of antibiotics similar to Late Onset/MDR Pathogen Nosocomial Pneumonia treatment
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Term
Recommended Antibiotics for Sepsis/Septic Shock |
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Definition
Antipseudomonal Cephalosporin
OR
Antipseudomonal Carbapenem
OR
β-Lactam/β-Lactamase Inhibitor
OR
Aztreonam (if β-Lactam allergy)
PLUS:
Antipseudomonal Fluoroquinolone
OR
Aminoglycoside
PLUS:
Vancomycin
OR
Linezolid
OR
Tigecycline
OR
Daptomycin |
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Term
Source/Site of Infection Control |
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Definition
- All pts presenting with signs and symptoms of sepsis should be evaluated for source/site of infection
- Unable to identify via physical assessment --> X-Ray/Ultrasound/CT Scan/MRS, etc.
- Once focal source identified:
Abcess - drainage/debridement
Wound - debridement of necrotic/infected tissue
Medical Device - removal of device if possible
- Evaluate risk vs benefit of intervention for source removal
- Inability/failure to remove source of infection prolongs sepsis and leads to poor outcomes
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Term
Duration of Antimicrobial Therapy |
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Definition
- 7-10 days recommended
- Should be dictated by patient response and site of infection
- Should treat for recommended duration for specific infection that caused sepsis (ie, endocarditis 4-6 weeks, osteomyelitis 4-6 weeks, etc.)
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Term
Reasoning behind corticosteroid use in sepsis/septic shock patients |
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Definition
- Relative Adrenal Insufficiency commonly occurs in sepsis:
-inflammatory cytokines released in response to infection suppress the cortisol response to Adrenocorticotropic Hormone (ACTH)
-this leads to relative adrenal insufficiency
-ultimately leads to deregulation of inflammatory process and loss of vascular tone --> hypotension
- Guidelines recommend use in septic shock when hypotension remains poorly responsive to adequate fluid resuscitation AND vasopressors
- Steroids may be DC'd or weaned once vasopressors are no longer required
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Term
What is the recommended corticosteroid therapy in sepsis/septic shock pts? |
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Definition
Hydrocortisone 200-300 mg IV divided 3-4 x daily
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Fludrocortisone 50 mcg PO daily
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Term
What are the Benefits/Risks of Corticosteroid therapy in pts with sepsis/septic shock? |
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Definition
Benefits:
- improvement in shock reversal in pts unresponsive to fluid resuscitation and vasopressors
Risks:
- immunosuppressive properties -- increasing risk of infection
- increased risk of critical care myopathy (especially when used while pt. on neuromuscular blockers)
- increased risk of GI bleed
- hyperglycemia
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Term
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Definition
- Recombinant activated protein C (rhAPC)
- Activated protein C decreased in sepsis leading to inflammation and coagulopathy
- rhAPC inhibits clotting factors Va and VIIIa --> ↓ thrombin production
- Also promotes anti-inflammatory (suppresses TNF-α, IL-1, and IL-6) and pro-fibrinolytic response
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Term
What pts should receive Drotrecogin Alpha? |
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Definition
- Adults with Sepsis-Induced Organ Dysfunction or Sepsis-Induced Acute Respiratory Distress Syndrome (ARDS)
- Clinical assessment of high-risk of death
- No contraindications
- Optimal results if started within 24 hrs of sepsis onset
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Term
Drotrecogin Alpha: Adverse Effects and Contraindications |
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Definition
Adverse Effect:
Bleeding
CI:
- Platelets < 30,000
- Hemorrhagic stroke within 3 months
- Severe head trauma
- Intracranial or intraspinal surgery within 2 months
- Need for epidural catheter
- Any factor that would increase likelihood of life-threatening bleeding
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Term
Supportive Therapy: Glucose Control |
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Definition
- Hyperglycemia associated w/ insulin resistance common in sepsis
- Prolonged hyperglycemia can lead to:
infectious complications
critical-illness polyneuropathy
multiple organ failure
- Target blood glucose 140-180 mg/dL
- ICU insulin protocols should be implemented
- Sliding-scale insulin protocols and/or continuous IV insulin
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Term
Supportive Therapy: Stress Ulcer Prophylaxis |
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Definition
- All patients with sepsis should receive stress ulcer prophylaxis
- H2 blocker (famotidine, ranitidine, etc.)
- Proton Pump Inhibitor (Omeprazole, Esomeprazole, etc.)
Risk Factors for Stress Ulcers:
- Mechanical ventilation
- Coagulopathy
- Acute renal failure
- Acute hepatic failure
- Major surgery
- Severe head trauma
- Major burns
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Term
Supportive Therapy: DVT Prophylaxis |
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Definition
- Incidence of DVT ranges from 10-80% in ICU patients
- All patients without CI should receive DVT prophylaxis with either:
Heparin 5000 units SubQ TID
Enoxaparin 40 mg SubQ daily
Fondaparinux 2.5 mg SubQ daily
- Patients with CI UFH/LMWH should receive mechanical prophylaxis (graduated compression stockings or intermittent compression devices)
- Very high risk pts should receive a combination of pharmacological therapy and mechanical therapy
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