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sepsis.pptx

26 Mar 2023
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sepsis.pptx

  1. SEPSIS PRESENTER: DR.B.N.SIREESHA MODERATOR: DR.SHAILAJA ASSISTANT PROFESSOR DEPARTMENT OF ANAESTHESIOLOGY, ASRAM MEDICAL COLLEGE
  2. DEFINITIONS INFECTION- When a pathogen is detected in blood or tissue. Bacteremia-presence of viable bacteria in the blood. SIRS-Defined as the generalized inflammatory response of the body to a variety of clinical conditions including infection but not limited to infection
  3. Response manifested by 2 or more of following: 1. Temperature >38˚c or <36˚c. 2. Heart rate >90bpm 3. Respiratory rate >20 beats/min or paco2<32mmhg. 4. WBC >12,000 cells/mm3,<4000mm3 or >10% immature (band) forms.
  4. Definitions  Sepsis-A life threatening condition caused by a dysregulated host response to infection, resulting in organ dysfunction.  Severe sepsis- progression of sepsis to organ dysfuntion ,tissue hypoperfusion or hypotension.  Septic shock-circulatory, cellular and metabolic abnormalities in septic patients, presenting as fluid refractory hypotension requiring vasopressor therapy with associated tissue hypoperfusion(lactate>2mmol/L).
  5. Definitions  MULTIPLE ORGAN DYSFUNCTION SYNDROME(MODS)- presence of altered organ function lasting for more than 24 hours in an acutely ill patients such that homeostasis cannot be maintained without intervention.  It is progressive dysfunction of 2 or more organs in acutely ill patients in whom homeostasis cannot be maintained without intervention
  6. Risk factors  elderly populations  Increasing invasive devices and procedures  In immunocompromised patients  Use of cytotoxic drugs and immunosuppressant agents  Malnutrition  Alcoholism  Malignancy  DM
  7. Risk factors  Transplant recipients and transplantation procedures  Community acquired and nosocomial infections  Antibiotic resistance  Burns ,wounds and multiple trauma
  8. Source of infection  Lung- strep pneumoniae, H influenzae,legionella sp, chlamedia pneumoniae  Abdomen-E coli, bacteriodes fragilis  Skin & soft tissue- strep pyogenes, staphy aureus,clostridum specis,  UTI- E coli, klebsiella sp, enterobater sp .  CNS- strep pneumoniae, N meningitidis,L monocytogenes, E coli,H influenzae
  9. Pathophysiology of sepsis  Innate immunity and inflammatory mediators:  The first step in the initiation of the host response to the pathogen is the activation of innate immune cells, constituted primarily by macrophages, monocytes, neutrophils, and natural killer cells. This occurs via the binding of pathogen-associated molecular patterns (PAMPs), such as bacterial endotoxins and fungal β-glucans to specific pattern recognition receptors, on these cells.
  10. pathophysiology  These bind to specific receptors on monocytes and macrophages such as toll-like receptors (TLRs), C-type leptin receptors, NOD-like receptors (nucleotide-binding oligomerization domain) and RIG-1 like receptors (retinoic acid inducible gene 1).  This results in release of pro inflammatory cytokines like TNF α, IL1 and IL 6.
  11. PATHOPHYSIOLOGY  Proinflammatory cytokines cause activation and proliferation of leukocytes, activation of the complement system, upregulation of endothelial adhesion molecules and chemokine expression, tissue factor production,and induction of hepatic acute phase reactants.
  12. PATHOPHYSIOLOGY Dysregulation of haemostasis:  activation of both the inflammatory and the coagulation cascades  The hypercoagulability of sepsis is thought to be driven by the release of tissue factor from disrupted endothelial cells (other sources include monocytes and polymorphonuclear cells).  Tissue factor then causes the systemic activation of the coagulation cascade resulting in the production of thrombin, activation of platelets, and formation of platelet–fibrin clots.
  13. pathophysiology  These microthrombi can cause local perfusion defects resulting in tissue hypoxia and organ dysfunction.  depression of the anticoagulant effects of protein C and antithrombin.  In patients with sepsis, there are decreased plasma levels of protein C, downregulation of thrombomodulin, and low levels of protein S  There is reduction in fibrinolysis and fibrin removal resulting in formation of microvascular thrombosis.
  14. pathophysiology Immunosupression:  immune system in a septic individual is unable to stage an effective immune response to secondary bacterial, viral, or fungal infections. Cellular, tissue and organ dysfunction:  Organ dysfunction mainly due to hypoperfusion due to cardiovascular dysfunction.  TNFα and IL-1β , can cause depression of cardiac myocytes and an interference with their mitochondrial function.
  15. pathophysiology  Second, the low left ventricular ejection fraction is accompanied by normal or low left ventricular filling pressures (unlike in cardiogenic shock) with increased left ventricular compliance.  arterial and venous dilation (induced by inflammatory mediators) and consequent reduced venous return, a state of hypotension and distributive shock is produced by sepsis.  Along with there is microvascular thrombosis resulting in hypoperfusion to tissues and organs.  Increase in anaerobic glycolysis resulting in lactate production.
  16. pathophysiology  The reactive oxygen species(ROS) causes dysregulation of mitochondria and drop in ATP levels.  There are significant alterations to the endothelium with disruption of its barrier function, vasodilation, increased leukocyte adhesion, and the creation of a procoagulant state. This results in accumulation of edema fluid in the interstitial spaces, body cavities, and subcutaneous tissue.
  17. Clinical features
  18. Severe sepsis  Pathogenesis of sever sepsis depends upon infecting microbe  Ability of host innate defense mechanisms to sense it  Site of primary infection  Presence or absence of immune defects  Prior physiological status of host  Genetic factors
  19. Organ dysfunction  Brains and kidneys are normally protected from swings in blood pressure by autoregulation  Late sepsis-vasoperesis occurs  Autoregulation fails.
  20. Septic shock and specific organ response  Regional circulation Altered blood flow  Microcirculation  Development of microthrombi Decreased functional capillaries Abnormal O2 utilization Increased microvascular permeability
  21. Specific organ response  Lung: V/Q mismatch Hypoxemia Increased microvascular permeability Interstitial/alveolar edema ARDS  Gastrointestinal: Impaired GI motility Bacterial translocation >> MODS Stress-ulcer GI bleeding Hepatic dysfunction
  22. Specific organ response  Kidney:  Altered renal function  ATN/ acute renal failure Increases mortality rate  Neurologic:  Encephalopathy  Peripheral polyneuropathy  Hematologic:  Leukocytosis/leukopenia  Thrombocytopenia  Coagulopathy- DIC  diffuse endothelial injury  microvascular thrombi
  23. Metabolic alterations in sepsis
  24. Signs and symptoms  Temperature ↑ or ↓  WBC ↑ or↓  Rigors  Sweating  Nausea and vomiting  Tachycardia  Hypotension  Tachyapnea(ALI)  Bounding pulse  Confusion  Oliguria and jaundice.
  25.  Increase glucose  Increase lactate  Increasingly negative base excess  Decreased albumin  Increased INR, APTT,  ↓ platelets.
  26. Identifying high risk
  27. Identifying high risk q sofa:  Respiratory rate at least 22 breaths/minute  Systolic blood pressure 100 mm Hg or lower  Altered mental status (Glasgow Coma Scale score < 15).  A qSOFA score of 2 or more with a suspected or confirmed infection was proposed as a trigger for aggressive treatment, including frequent monitoring and ICU admission.  qSOFA has the advantage of its elements being easy to obtain in clinical practice.
  28. Investigations Basic WBC Platelets Coagulation factors Renal function Glucose Albumin LFT ABG Specific ?Source Urine CxR Blood Cultures x 2 LP Aspirate Biopsy
  29. Diagnosis  Before the initiation of antimicrobial therapy, at least two blood cultures should be obtained  Other cultures such as urine, cerebrospinal fluid, wounds, respiratory secretions or other body fluids should be obtained as the clinical situation dictates  Other diagnostic studies such as imaging and sampling should be performed promptly to determine the source and causative organism of the infection
  30. Biomarkers  C-Reactive protein and erythrocyte sedimentation rate.  Procalcitonin: has emerged as a method to help detect bacterial infections early and to guide de-escalation or discontinuation of antibiotics.  Procalcitonin-guided de-escalation of antibiotics reduces duration of antibiotic exposure.  Galactomannan and beta-D-glucan can be used to detect infections with fungi, specially Aspergillus. Beta-d-glucan is more sensitive for invasive Aspergillus, while galactomannan is more specific.
  31. Biomarkers  Cytokines such as interleukins (eg, IL-6, IL-8, IL-10), tumor necrosis factor alpha,acute-phase proteins.  The decision to initiate, escalate, and de-escalate therapy should be based on clinical assessment, with procalcitonin or other biomarkers used as an adjunct to other clinical factors.
  32. Surviving Sepsis Campaign  Guidelines for the management of severe sepsis and septic shock.  This include sepsis resuscitation bundle(3hour bundle) and sepsis management bundle(6hour bundle).  Therapeutic goals to be completed in 3 hours and 6 hours.  In 2018 3 & 6 hour bundles are combined as Single 1 hour bundle.
  33. Lactate level as a resuscitation guide  Lactate-guided resuscitation can significantly lessen the high mortality rate associated with elevated lactate levels (> 4 mmol/L).  A rise in lactate during sepsis can be due to tissue hypoxia, accelerated glycolysis from a hyperadrenergic state,or liver failure.  Measuring the lactate level is an objective way to assess response to resuscitation, better than other clinical markers,
  34. Management Antibiotic therapy:  Start intravenous antibiotic therapy within the first hour of recognition of severe sepsis after obtaining appropriate cultures  Empirical choice of antimicrobials should include one or more drugs with activity against likely pathogens, both bacterial or fungal  Penetrate presumed source of infection  Guided by susceptibility patterns in the community and hospital  Continue broad spectrum therapy until the causative organism and its susceptibilities are defined
  35. Management  Reassess after 48-72 hours to narrow the spectrum of antibiotic therapy  Duration of therapy should typically be 7-10 days and guided by clinical response . ANTIFUNGAL:  Antifungals should be considered for patients at risk, such as those who have had total parenteral nutrition, recent broad-spectrum antibiotic exposure, perforated abdominal viscus, or immunocompromised status, or when clinical suspicion of fungal infection is high
  36. Source control  Evaluate patients for focus of infection amenable to source control measures  Drainage of an abscess or local focus of infection  Debridement of infected necrotic tissue  Removal of a potentially infected device  Definitive control of a source of ongoing microbial contamination
  37. Fluid resuscitation  The goals of resuscitation in sepsis and septic shock are to restore intravascular volume, increase oxygen delivery to tissues, and reverse organ dysfunction.  A crystalloid bolus of 30 mL/kg is recommended within 3 hours of detecting severe sepsis or septic shock.  Excess fluid administration can result in pulmonaryedema, hypoxemic respiratory failure, organ edema, intra-abdominal hypertension, prolonged ICU stay and time on mechanical ventilation, and even increased risk of death.
  38. Fluid resuscitation  fluid resuscitation should be managed as follows during consecutive phases:  Rescue: During the initial minutes to hours, fluid boluses (a 1- to 2-L fluid bolus of crystalloid solution) are required to reverse hypoperfusion and shock  Optimization: During the second phase, the benefits of giving additional fluid to improve cardiac output and tissue perfusion should be weighed against potential harms.  Stabilization: During the third phase, usually 24 to 48 hours after the onset of septic shock, an attempt should be made to achieve a net-neutral or a slightly negative fluid balance  De-escalation: The fourth phase, marked by shock resolution and organ recovery, should trigger aggressive fluid removal
  39. vasopressors  Nor epinephrine: is the 1st line vasopressor.  norepinephrine remains the preferred vasopressor for achieving the target mean arterial pressure and is strongly recommended by the Surviving Sepsis Campaign guidelines.  A second vasopressor is routinely added when norepinephrine doses exceed 40 or 50 μg/min.  Vasopressin. Septic shock involves relative vasopressin deficiency. Adding vasopressin as a replacement hormone has been shown to have a sparing effect on norepinephrine, resulting in a lower dose needed.
  40. vasopressors  Epinephrine is recommended by the Surviving Sepsis Campaign guidelines as a second-line vasopressor. It has potent alpha and beta-adrenergic activity, which increases mean arterial pressure by increasing cardiac output and vasomotor tone.  Use of epinephrine is limited by significant risk of tachycardia, arrhythmia, and transient lactic acidosis.  Dopamine: particularly useful in patients with compromised systolic function but causes more tachycardia and may be more arrhythmogenic.  Phenylephrine: used as adjunct for refractory vasodilatory shock.
  41. Inotropes  Inotropic agents may be required for patients with inadequate CO after fluid resuscitation due to sepsis induced cardiomyopathy or combined shock  Epinephrine and dobutamine are most commonly used.  Response to use of inotropes should be monitored by measuring change in CO and central venous oxygen saturation.
  42. corticosteroids  Not recommended in sepsis or severe sepsis if fluid resuscitation and vasopressors are sufficient to restore hemodynamic stability  If corticosteroids are used in septic shock,current guidelines recommend hydrocortisone  200 mg per day intravenously as a continuous drip or 50 mg bolus in 4 divided doses. for at least 3 days,  a longer course of low-dose steroids is associated with a lower mortality rate
  43.  Blood glucose correction: target 80 to 150mg/dl.  Red cells, FFP and platelet: keep hemoglobin between 7 to 9 g/dl.  FFP only to cover invasive procedures and surgery.  Platelet transfusion to keep counts >50,000mm3 for invasive procedure and surgery.  Mechanical ventilation: limit tidal volume 6 to 8 ml/kg lean mass and plateau pressure<30cm h20.  Hemodialysis: Support for acute renal failure by continuous veno venous hemo filteration.
  44. Deep vein thrombosis prophylaxis  DVT prophylaxis with either low-dose unfractionated heparin or low molecular weight heparin should be used in severe sepsis patients  Use a mechanical prophylactic device or intermittent compression in patients with contraindications to heparin  Use a combination of pharmacological and mechanical therapy in very high risk patients (eg, severe sepsis and history of DVT).
  45. Strees ulcer prophylaxis  Stress ulcer prophylaxis should be given to all patients with severe sepsis  H2 receptor blockers are more efficacious than sucralfate and are the preferred agents
  46. Thank you
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