Post on 14-Nov-2014
description
SHOCKSHOCK“A rude unhinging of the machinery of
life”
- Gross -: RAJAN
KUMAR
DefinitionDefinition Shock is a systemic state of low Shock is a systemic state of low
tissue perfusion, which is tissue perfusion, which is inadequate for normal cellular inadequate for normal cellular respiration. With insufficient respiration. With insufficient delivery of oxygen and glucose, cells delivery of oxygen and glucose, cells switch from aerobic to anaerobic switch from aerobic to anaerobic metabolism. If perfusion is not metabolism. If perfusion is not restored in a timely fashion, cell restored in a timely fashion, cell death ensues.death ensues.
PathophysiologyPathophysiology Physiologic response to hypovolemia Physiologic response to hypovolemia
directed at preservation of perfusion to directed at preservation of perfusion to vital organsvital organs
-Increase cardiac contractility & -Increase cardiac contractility & peripheral peripheral vascular tone via ANSvascular tone via ANS
-Hormonal response to preserve salt & -Hormonal response to preserve salt & waterwater
-Change in local micro circulation to -Change in local micro circulation to regulate regulate
regional blood flow regional blood flow
Cellular responseCellular response Inadequate delivery of oxygen Inadequate delivery of oxygen
& substrates leads to in & substrates leads to in oxidative phosphorylation & ATP oxidative phosphorylation & ATP generation.generation.
Anaerobic respiration leads to Anaerobic respiration leads to lactic acidosis.lactic acidosis.
Na+,K+ ATP ase activity Na+,K+ ATP ase activity decrease leading to decrease leading to accumulation of Na+ & leak of accumulation of Na+ & leak of K+K+
Intracellular lysosomes release Intracellular lysosomes release autodigestive enzymes & cell autodigestive enzymes & cell lysis ensues leading to release of lysis ensues leading to release of K+ into bloodstream.K+ into bloodstream.
Cellular responseCellular response
MicrovascularMicrovascularProgressive tissue ischemiaProgressive tissue ischemia
Change in local milieuChange in local milieu
(hypoxia & acidosis)(hypoxia & acidosis)
Activation of immune & coagulation Activation of immune & coagulation systemsystem
(compliment & prime neutrophils)(compliment & prime neutrophils)
O2 free radical & cytokineO2 free radical & cytokine
Injury of capillary endothelial cellsInjury of capillary endothelial cells
(becomes ‘leaky’)(becomes ‘leaky’)
Tissue oedemaTissue oedema
Cellular hypoxiaCellular hypoxia
Contd.
SystemicSystemic CardiovascularCardiovascular
in preload & afterloadin preload & afterload
Compensatory baroreceptor activationCompensatory baroreceptor activation
Sympathetic activitySympathetic activity
Tachycardia & systemic Tachycardia & systemic vasoconstrictionvasoconstriction
Arterial Baroreceptors
Autonomic Responses toBaroreceptor Activity
Arterial baroreceptor firing inhibits sympathetic outflow and stimulates parasympathetic outflow
Therefore, reduced firing, which occurs during hemorrhage, leads to sympathetic activation and parasympathetic inhibition
Cardiopulmonary Baroreceptors
• Location: Venoatrial Junction – Tonically active • Receptor firing decreases ADH
(vasopressin) release leading to diuresis and vasodilation
• Hemorrhage → increase ADH (reduced urine formation and increased vasoconstriction)
• Location: Atria and Ventricles – Tonically active • affect vagal and sympathetic outflow
similar to arterial baroreceptors • reinforce arterial baroreceptor responses
during hypovolemia
Baroreceptor Reflexes
Chemoreceptor Reflexes
Peripheral chemoreceptors – Carotid bodies – Aortic bodies
Central chemoreceptors – Medulla (associated with
cardiovascular control “centers”)
Increasingly important when mean arterial pressure falls below 60 mmHg (i.e., when arterial baroreceptor firing rate is at minimum)
Acidosis resulting from decreased organ perfusion stimulates central and peripheral chemoreceptors → sympathetic activation
Stagnant hypoxia in carotid bodies enhances peripheral vasoconstriction
Respiratory stimulation may enhance venous return (abdominothoracic pump)
Contd.
RespiratoryRespiratoryMetabolic acidosis & sympathetic Metabolic acidosis & sympathetic
responseresponse
R.Rate & MVR.Rate & MV
(excretion of Co2)(excretion of Co2)
Compensatory respiratory Compensatory respiratory alkalosisalkalosis
RenalRenal
EndocrineEndocrine Vasopressin (ADH) released from Vasopressin (ADH) released from
hypothalamus in response to preload hypothalamus in response to preload vasoconstriction & reabsorption vasoconstriction & reabsorption of water in collecting system.of water in collecting system.
Cortisol released from adrenal cortex Cortisol released from adrenal cortex Na+ & H2O reabsorption and Na+ & H2O reabsorption and sensitising the cells to sensitising the cells to catecholamines.catecholamines.
HypothalamusHypothalamus
HyperglycemiaLypolysisGluconeogenesisGlycogenolysis
Cortisol
ACTH
CRH
Hormonal responseHormonal response
Ischaemia-reperfusion Ischaemia-reperfusion syndromesyndrome
During the period of systemic During the period of systemic hypoperfusion, cellular and organ hypoperfusion, cellular and organ damage progresses because of direct damage progresses because of direct effects of hypoxia & local activation of effects of hypoxia & local activation of inflammation.inflammation.
Further injury occurs once normal Further injury occurs once normal circulation is restored to these tissues.circulation is restored to these tissues.
The acid & K+ load can lead toThe acid & K+ load can lead to
-direct myocardial depression-direct myocardial depression
-vascular dilatation & further -vascular dilatation & further hypotension.hypotension.
HypoxiaHypoxia
Cellular & humoral componentsCellular & humoral components
Flushed back into circulationFlushed back into circulation
Endothelial injury(lungs,kidney)Endothelial injury(lungs,kidney)
Ischaemia-reperfusion Ischaemia-reperfusion syndromesyndrome
Acute lung,kidney injury,Acute lung,kidney injury,
multi organ failure & deathmulti organ failure & death
This injury can be attenuated by This injury can be attenuated by reducing the extent and duration of reducing the extent and duration of tissue hypoperfusiontissue hypoperfusion
Ischaemia-reperfusion Ischaemia-reperfusion syndromesyndrome
ClassificationClassification HypovolaemicHypovolaemic CardiogenicCardiogenic ObstructiveObstructive DistributiveDistributive EndocrineEndocrine
TypesTypes
Hypovolaemic shockHypovolaemic shock -Due to reduced circulating volume.-Due to reduced circulating volume.
1.1. HaemorrhagicHaemorrhagic
2.2. Non-HaemorrhagicNon-Haemorrhagic Causes of non-haemorrhagic shockCauses of non-haemorrhagic shock
--Dehydration,diarrhoea,vomiting,evaDehydration,diarrhoea,vomiting,evaporation,3poration,3rdrd space loss, bowel space loss, bowel obstruction or pancreatitis.obstruction or pancreatitis.
Cardiogenic shockCardiogenic shock Primary failure of the heart to pump.Primary failure of the heart to pump.
CausesCauses
-MI, cardiac dysrhytmias, valvular -MI, cardiac dysrhytmias, valvular heart disease,blunt myocardial heart disease,blunt myocardial injury,cardiomyopathy.injury,cardiomyopathy.
-d/t endogenous factors (in sepsis)-d/t endogenous factors (in sepsis)
-d/t exogenous factors (drugs)-d/t exogenous factors (drugs)
TypesTypes
Obstructive shockObstructive shock Reduction in preload due to Reduction in preload due to
mechanical obstruction of cardiac mechanical obstruction of cardiac filling.filling.
CausesCauses
- cardiac tamponade, tension - cardiac tamponade, tension pneumothorax, massive pulmonary pneumothorax, massive pulmonary embolus, air embolus.embolus, air embolus.
TypesTypes
Distributive shockDistributive shock Inadequate organ perfusion Inadequate organ perfusion
accompanied byaccompanied by
1.1. Vascular dilatation with Vascular dilatation with hypotensionhypotension
2.2. Low SVRLow SVR
3.3. Inadequate afterloadInadequate afterload
4.4. Abnormally high cardiac outputAbnormally high cardiac output
TypesTypes
CausesCauses
--Septic shockSeptic shock -Anaphylaxis-Anaphylaxis
-Spinal cord injury-Spinal cord injury
TypesTypes
Endocrine shockEndocrine shock Combination of hypovolaemic, Combination of hypovolaemic,
cardiogenic & distributive cardiogenic & distributive shock.shock.
CausesCauses
-Hypo- & hyperthyroidism-Hypo- & hyperthyroidism
-Adrenal insufficiency-Adrenal insufficiency
TypesTypes
Cardiovascular & metabolic Cardiovascular & metabolic characteristicscharacteristics
hypovolaehypovolaemiamia
cardiogecardiogenicnic
obstructobstructiveive
distributdistributiveive
Cardiac Cardiac outputoutput
lowlow lowlow lowlow HighHigh
VasculaVascular r resistanresistancece
highhigh highhigh highhigh lowlow
Venous Venous pressurpressuree
LowLow HighHigh highhigh LowLow
Base Base deficitdeficit
highhigh highhigh highhigh highhigh
Severity of shockSeverity of shock Compensated shockCompensated shock DecompensationDecompensation Mild shockMild shock Moderate shockModerate shock Severe shockSevere shock
Clinical featuresClinical featurescompensacompensa
tedtedmildmild moderatmoderat
eeseveresevere
Lactic Lactic acidosisacidosis
++ ++++ ++++ ++++++
UOPUOP normalnormal normalnormal oliguricoliguric AnuricAnuric
Level of Level of consciouconsciou
snesssness
NormalNormal Mild Mild anxietyanxiety
drowsydrowsy ComatComatoseose
R.RateR.Rate NormalNormal IncreasedIncreased IncreaseIncreasedd
LabourLaboureded
PulsePulse Mild Mild increaseincrease
increasedincreased increaseincreasedd
increasincreaseded
B.P.B.P. normalnormal normalnormal Mild lowMild low Severe Severe lowlow
Clinical MarkersClinical Markers Brachial systolic blood pressure:
<110mmHg Sinus tachycardia: >90 beats/min Respiratory rate: <7 or >29
breaths/min Urine Output: <0.5cc/kg/hr Metabolic acidemia:
[HCO3]<31mEq/L or base deficit>3mEq/L
Hypoxemia: 0-50yr: <90mmHg; 51-70yr: <80mmHg; >71yo; <70mmHg;
Cutaneous vasoconstriction vs. vasodilation.
Mental Changes: anxiousness, agitation, indifference, lethargy, obtundation
Prolonged capillary refill timeProlonged capillary refill time
Contd.
PitfallsPitfalls Capillary refillCapillary refill -prolonged-prolonged
-not a specific marker. (varies in -not a specific marker. (varies in adults)adults)
-if short then may be early stage of -if short then may be early stage of shockshock
-in -in septic shockseptic shock:- BRISK despite :- BRISK despite of profound shockof profound shock
TachycardiaTachycardia- Not always accompany shockNot always accompany shock- Who on Who on ββ-blocker or have implanted -blocker or have implanted
pacemakers unable to mount pacemakers unable to mount tachycardiatachycardia
- A pulse rate of 80 in a fit young adult A pulse rate of 80 in a fit young adult who normally has a pulse of 50 is who normally has a pulse of 50 is abnormalabnormal
Contd.
Blood pressureBlood pressure- Hypotension is one of the last signHypotension is one of the last sign- Children & fit young adults are able to Children & fit young adults are able to
maintain B.P. until the final stages maintain B.P. until the final stages (compensatory mechanism lead to in SV (compensatory mechanism lead to in SV & peripheral vasoconstriction)& peripheral vasoconstriction)
- Elderly hypertensive pts may present Elderly hypertensive pts may present with ‘normal’ BP but be hypovolemic & with ‘normal’ BP but be hypovolemic & hypotensivehypotensive
- ββ-blocker may prevent tachycardic -blocker may prevent tachycardic responseresponse
Contd.
Consequences Consequences Unresuscitable shockUnresuscitable shock- Profound shock for a prolonged period of Profound shock for a prolonged period of
timetime- Cell death follows from cellular ischemiaCell death follows from cellular ischemia- Ability to compensate lostAbility to compensate lost- Myocardial depressionMyocardial depression- Non responsive to fluid or ionotropesNon responsive to fluid or ionotropes- Peripherally loss of ability to maintain Peripherally loss of ability to maintain
SVRSVR- Further hypotension ensuesFurther hypotension ensues- Death is inevitableDeath is inevitable
Multiple organ failureMultiple organ failure- Defined as 2 or more failed organ Defined as 2 or more failed organ
systemssystems- No specific treatmentNo specific treatment- Supporting organ systems with Supporting organ systems with
ventilation, cardiovascular support & ventilation, cardiovascular support & dialysis until there is recovery of dialysis until there is recovery of functionfunction
- Mortality rate 60%Mortality rate 60%- Prevention by early aggressive Prevention by early aggressive
identification & reversal of shockidentification & reversal of shock
Contd.
Effects of organ failureEffects of organ failure
Lung Lung ARDSARDS
Kidney Kidney Acute renal Acute renal insufficiencyinsufficiency
Liver Liver Acute liver Acute liver insufficiencyinsufficiency
Clotting Clotting CoagulopathyCoagulopathy
Cardiac Cardiac Cardiovascular Cardiovascular failure failure
ResuscitationResuscitationA – airwayA – airwayB – breathing i.e. B – breathing i.e.
oxygenation & ventilationoxygenation & ventilationC – circulation C – circulation
(cardiovascular (cardiovascular resuscitation) resuscitation)
Conduct of resuscitationConduct of resuscitation- Should not be delayedShould not be delayed- Timing & nature of resuscitation Timing & nature of resuscitation
depend on type of shock and timing & depend on type of shock and timing & severity of insultseverity of insult
- Rapid examination to make a diagnosis Rapid examination to make a diagnosis & detect the source& detect the source
- If there is doubt about cause it is safer If there is doubt about cause it is safer to assume the cause is hypovolemia. to assume the cause is hypovolemia. Begin with fluid resuscitationBegin with fluid resuscitation
Contd.
The pts who are actively bleeding it is The pts who are actively bleeding it is counterproductive to institute high counterproductive to institute high volume fluid therapyvolume fluid therapy
Operative hemorrhage control should Operative hemorrhage control should not be delayed & resuscitation should not be delayed & resuscitation should proceed in parallel with surgeryproceed in parallel with surgery
A pt with bowel obstruction & A pt with bowel obstruction & hypovolemic shock must be hypovolemic shock must be adequately resuscitated before adequately resuscitated before undergoing surgeryundergoing surgery
Contd.
Fluid therapyFluid therapy- Hypovolemia & inadequate preload Hypovolemia & inadequate preload
must be addressed 1must be addressed 1stst
- First-line therapy is IV access and First-line therapy is IV access and administration of IV fluidsadministration of IV fluids
- Short wide bore catheters preferredShort wide bore catheters preferred- Central venous catheters are more Central venous catheters are more
appropriate for monitoringappropriate for monitoring
Contd.
Type of fluidType of fluid- There is no ideal resuscitation fluidThere is no ideal resuscitation fluid- It is more important to understand It is more important to understand
how & when to administer themhow & when to administer them- Crystalloid vs ColloidCrystalloid vs Colloid- Their O2 carrying capacity zeroTheir O2 carrying capacity zero- Blood should be replaced with bloodBlood should be replaced with blood- Hypotonic solution like dextrose Hypotonic solution like dextrose
should not be used unless the deficit should not be used unless the deficit is free water loss(DI) or Na+ is free water loss(DI) or Na+ overload (cirrhosis)overload (cirrhosis)
Contd.
Dynamic fluid responseDynamic fluid response- Shock status can be determined by Shock status can be determined by
the cardiovascular response to the the cardiovascular response to the rapid administration of a fluid bolusrapid administration of a fluid bolus
- InterpretationInterpretation
1.1. RespondersResponders
2.2. Transient respondersTransient responders
3.3. Non-respondersNon-responders
Contd.
Vasopressor and inotropic supportVasopressor and inotropic support- Not indicated as 1Not indicated as 1stst line therapy in line therapy in
hypovolemiahypovolemia- Vasopressor agents (phenylepherine, nor-Vasopressor agents (phenylepherine, nor-
adrenaline) used in distributive shock stateadrenaline) used in distributive shock state- If vasodilation is resistant to If vasodilation is resistant to
catecholamines, vasopressin may be usedcatecholamines, vasopressin may be used- Inotropic therapy required for cardiogenic Inotropic therapy required for cardiogenic
shockshock- Inodilator dobutamine is agent of choiceInodilator dobutamine is agent of choice
Contd.
MonitoringMonitoring MinimumMinimum- ECGECG- Pulse oximetryPulse oximetry- Blood pressureBlood pressure- Urine outputUrine output
Additional Additional modalitiesmodalities
- Central venous Central venous pressurepressure
- Invasive Blood Invasive Blood pressurepressure
- Cardiac outputCardiac output- Base deficit and Base deficit and
serum lactateserum lactate
Cardiovascular Cardiovascular monitoringmonitoring Central venous pressureCentral venous pressure- There is no ‘normal’ CVP for a shocked pt.There is no ‘normal’ CVP for a shocked pt.- It varies patient to patientIt varies patient to patient- Ventricular compliance can change Ventricular compliance can change
rapidlyrapidly- It is a poor reflection of preloadIt is a poor reflection of preload- Measurement during fluid challenge testMeasurement during fluid challenge test- Normal response is a rise of 2-5 cmH2ONormal response is a rise of 2-5 cmH2O- Pt with no change,require more fluidPt with no change,require more fluid- With large CVP have high preloadWith large CVP have high preload
Cardiac outputCardiac output- AssesesAsseses
1.1. Cardiac functionCardiac function
2.2. Systemic vascular resistanceSystemic vascular resistance
3.3. Preload (end-diastolic volume)Preload (end-diastolic volume)
4.4. Blood volumeBlood volume
Contd.
Systemic & organ Systemic & organ perfusionperfusion
Goal of t/t is to restore cellular & Goal of t/t is to restore cellular & organ perfusionorgan perfusion
UOP is the best monitorUOP is the best monitor Level of consciousness – marker of Level of consciousness – marker of
cerebral perfusioncerebral perfusion Clinical indicators of perfusion of GIT Clinical indicators of perfusion of GIT
& muscular beds are lactate & base & muscular beds are lactate & base deficit and the mixed venous oxygen deficit and the mixed venous oxygen saturationsaturation
ClinicalClinical InvestigationaInvestigationall
SystemSystemic ic perfusiperfusionon
Base deficit; lactate; Base deficit; lactate; mixed venous O2 sat.mixed venous O2 sat.
Organ Organ perfusiperfusionon
Muscle Muscle -- Near infrared Near infrared spectroscopyspectroscopy
Gut Gut -- Sublingual Sublingual capnometry;pcapnometry;pH;flowmetryH;flowmetry
Kidney Kidney UOPUOP --
Brain Brain Level of consciousnessLevel of consciousness Near infrared Near infrared spectroscopyspectroscopy
Base deficit and lactateBase deficit and lactate
Sensitive tool for both diagnosis and Sensitive tool for both diagnosis and monitoringmonitoring
>6mmol/l have higher morbidity & >6mmol/l have higher morbidity & mortalitymortality
Occult hypoperfusion- state of normal Occult hypoperfusion- state of normal vital signs and continued vital signs and continued underperfusion manifested by ed underperfusion manifested by ed base deficitbase deficit
ABG measurementABG measurement
Mixed venous oxygen Mixed venous oxygen saturationsaturation % saturation of oxygen returning to % saturation of oxygen returning to
heart from bodyheart from body Measure of O2 delivery & extraction Measure of O2 delivery & extraction
by tissuesby tissues measurement ;- sample from rt atriummeasurement ;- sample from rt atrium 50-70% normal50-70% normal <50% indicate inadequate O2 <50% indicate inadequate O2
delivery & ed O2 extraction by cellsdelivery & ed O2 extraction by cells In hypovolemic or cardiogenic shockIn hypovolemic or cardiogenic shock
>70% in sepsis>70% in sepsis Disordered utilisation of O2 at Disordered utilisation of O2 at
cellular levelcellular level Arteriovenous shunting of bloodArteriovenous shunting of blood Rapid correction required withRapid correction required with- Fluid therapyFluid therapy- InotropesInotropes
Contd.
Endpoints of Endpoints of resuscitationresuscitation
Resuscitation complete when oxygen Resuscitation complete when oxygen debt repaid,tissue acidosis corrected debt repaid,tissue acidosis corrected & aerobic metabolism restored & aerobic metabolism restored
Systemic ParametersSystemic Parameters LactateLactate Base deficitBase deficit Tissue ParametersTissue Parameters Gastric tonometeryGastric tonometery Near infrared spectroscopy Near infrared spectroscopy
Sepsis in a Sepsis in a surgical patientsurgical patient
Shock associated with sepsis is Shock associated with sepsis is found to be major cause of death found to be major cause of death in surgical intensive carein surgical intensive care
Incidence of sepsis has increased Incidence of sepsis has increased steadily over timesteadily over time
Cause of this is Cause of this is - widespread use of - widespread use of
antimicrobials, steroids, antimicrobials, steroids, indwelling catheters & ventilatorsindwelling catheters & ventilators
What is sepsis?What is sepsis? Sepsis can be response to any class of Sepsis can be response to any class of
micro organism that may spread micro organism that may spread beyond invaded tissuebeyond invaded tissue
Microbial bloodstream invasion not Microbial bloodstream invasion not essentialessential
Fever or hypothermia, tachypnea, Fever or hypothermia, tachypnea, tachycardia herald onsettachycardia herald onset
When counter regulatory mechanisms When counter regulatory mechanisms overwhelmed, homeostasis fails causing overwhelmed, homeostasis fails causing organ dysfunction and further organ dysfunction and further imbalance leads to hypotensionimbalance leads to hypotension
Definitions in sepsisDefinitions in sepsis Bacteremia Bacteremia – presence of bacteria in blood – presence of bacteria in blood
with +ve blood cultureswith +ve blood cultures
SepticemiaSepticemia – presence of bacteria + toxins in – presence of bacteria + toxins in bloodblood
Systemic inflammatory response Systemic inflammatory response syndromesyndrome (SIRS) – may have infectious or (SIRS) – may have infectious or noninfectious aetiologynoninfectious aetiology
2 or more of following conditions2 or more of following conditions - fever or hypothermia- fever or hypothermia - tachycardia- tachycardia - tachypnea- tachypnea - leukocytosis or leukopenia or > 10% bands- leukocytosis or leukopenia or > 10% bands
SepsisSepsis – SIRS with a documented – SIRS with a documented INFECTIONINFECTION
Severe SepsisSevere Sepsis or or Sepsis SyndromeSepsis Syndrome – Sepsis with evidence of one or – Sepsis with evidence of one or more organ failures [respiratory more organ failures [respiratory (ARDS), cardiovascular (compromise (ARDS), cardiovascular (compromise of cardiac function & in PVR ), renal of cardiac function & in PVR ), renal (ATN), hepatic, blood coagulation (ATN), hepatic, blood coagulation system or CNS]system or CNS]
Contd.
SUSPECT SEVERE SUSPECT SEVERE SEPSIS IFSEPSIS IF
systolic BP <90 mm Hg or > 40 mm systolic BP <90 mm Hg or > 40 mm Hg fall from pts normal BPHg fall from pts normal BP
hypoxemiahypoxemia lactic acidemialactic acidemia oliguriaoliguria acute encephalopathyacute encephalopathy Hypotension unresponsive to fluid Hypotension unresponsive to fluid
resuscitation denotes septic shockresuscitation denotes septic shock
OMINOUS SIGNSOMINOUS SIGNS
Septic shock lasts for > 1 hr and Septic shock lasts for > 1 hr and does not respond to fluid or pressor does not respond to fluid or pressor administration : Refractory septic administration : Refractory septic shockshock
Dysfunction of > 1 organ requiring Dysfunction of > 1 organ requiring intervention to maintain intervention to maintain homeostasis: Multiple organ homeostasis: Multiple organ dysfunction syndrome –dysfunction syndrome –
Organisms causing Organisms causing sepsissepsis
Gram +ve Gram +ve - staph. Aureusstaph. Aureus- enterococcus,enterococcus,- coagulase –ve staphcoagulase –ve staph Gram –ve Gram –ve - E. coliE. coli- KlebsiellaKlebsiella- Pseudomonas Pseudomonas
PathophysiologyPathophysiology
Septic insult
Complement activation Macrophage activation
TNF, IL – 1,6
Neutrophil activation
Endothelial cellUp regulation
bradykinin coagulationArachidonic metabolites N2O Oxygen radicals
Capillary leak microthrombosis vasodilation vasodilationTissue
destruction
Organ injury
Complications of sepsisComplications of sepsis
Cardiopulmonary – ARDS, arteriolar Cardiopulmonary – ARDS, arteriolar vasodilatation, myocardial dysfunctionvasodilatation, myocardial dysfunction
Renal – acute tubular necrosisRenal – acute tubular necrosis
Coagulation – thrombocytopenia, Coagulation – thrombocytopenia, disseminated intravascular coagulationdisseminated intravascular coagulation
Neurological - polyneuropathyNeurological - polyneuropathy
Initial ResuscitationInitial Resuscitation
Should begin as soon as severe sepsis or sepsis induced tissue hypoperfusion recognized
Elevated Serum lactate identifies tissue hypoperfusion in patients not hypotensive
Initial ResuscitationInitial Resuscitation
Goals of therapy within first 6 hours
- - Central Venous Pressure 8-12 mm Central Venous Pressure 8-12 mm Hg (12-15 in ventilator pts)Hg (12-15 in ventilator pts)
- Mean arterial pressure > 65 mm HgMean arterial pressure > 65 mm Hg- Urine output > 0.5 mL/kg/hrUrine output > 0.5 mL/kg/hr- ScvO2 or SvO2 ≥ 70%; ScvO2 or SvO2 ≥ 70%;
Initial ResuscitationInitial Resuscitation
- if not achieved with fluid if not achieved with fluid resuscitation during first 6 hours:resuscitation during first 6 hours:
- Transfuse RCC to hematocrit > Transfuse RCC to hematocrit > 30%30%
- Administer dobutamine (max 20 Administer dobutamine (max 20 mcg/kg/min) to goalmcg/kg/min) to goal
DiagnosisDiagnosis
Before the initiation of Before the initiation of antimicrobial, at least antimicrobial, at least two blood two blood culturescultures should be obtained should be obtained
- At least one drawn At least one drawn percutaneouslypercutaneously
- At least one drawn through At least one drawn through each vascular access device if each vascular access device if inserted longer than 48 hoursinserted longer than 48 hours
DiagnosisDiagnosis
Cultures such as urine, Cultures such as urine, cerebrospinal fluid, wounds, cerebrospinal fluid, wounds, respiratory secretions obtained as respiratory secretions obtained as clinical situation dictatesclinical situation dictates
Imaging and sampling performed Imaging and sampling performed promptly to determine source promptly to determine source and causative organism and causative organism
may be limited by patient stabilitymay be limited by patient stability
Source ControlSource Control
Evaluate patients for focus of infection Evaluate patients for focus of infection amenable to source control measuresamenable to source control measures
Drainage of an abscess or local focus of Drainage of an abscess or local focus of infectioninfection
Debridement of infected necrotic tissueDebridement of infected necrotic tissue Removal of a potentially infected deviceRemoval of a potentially infected device Definitive control of a source of ongoing Definitive control of a source of ongoing
microbial contaminationmicrobial contamination
Source control methods must weigh Source control methods must weigh benefits and risks of specific benefits and risks of specific interventionintervention
Antibiotic TherapyAntibiotic Therapy
Start i.v. antibiotics within 1st Start i.v. antibiotics within 1st hr of recognition of severe hr of recognition of severe sepsis after obtaining cultures sepsis after obtaining cultures
Antibiotic TherapyAntibiotic Therapy Empirical choice of antimicrobials Empirical choice of antimicrobials
should include 1 or more drugs with should include 1 or more drugs with activity against likely pathogens, activity against likely pathogens, bacterial & fungalbacterial & fungal1.1. Penetrate presumed source of infectionPenetrate presumed source of infection
2.2. Guided by susceptibility patterns in Guided by susceptibility patterns in hospitalhospital
3.3. Continue broad spectrum therapy until Continue broad spectrum therapy until causative organism and causative organism and susceptibilities definedsusceptibilities defined
Reassess after 48-72 hours to Reassess after 48-72 hours to narrow spectrum of therapynarrow spectrum of therapy
Duration of therapy should be 7-Duration of therapy should be 7-
10 days and guided by clinical 10 days and guided by clinical responseresponse
Antibiotic TherapyAntibiotic Therapy
Some experts prefer combination Some experts prefer combination therapy for therapy for Pseudomonas Pseudomonas infections or neutropenic patientsinfections or neutropenic patients
Stop antimicrobials promptly if Stop antimicrobials promptly if clinical syndrome is determined clinical syndrome is determined to be noninfectiousto be noninfectious
Antibiotic TherapyAntibiotic Therapy
Fluid Therapy: Choice of Fluid Therapy: Choice of FluidFluid
Fluid resuscitation consists of natural Fluid resuscitation consists of natural or artificial colloids or crystalloidsor artificial colloids or crystalloids
No evidenced-based support for one No evidenced-based support for one type of fluid over anothertype of fluid over another
- Crystalloids have much larger volume Crystalloids have much larger volume of distribution compared to colloidsof distribution compared to colloids
- Crystalloid resuscitation requires more Crystalloid resuscitation requires more fluid to achieve same endpoints as fluid to achieve same endpoints as colloidcolloid
- Crystalloids result in more edemaCrystalloids result in more edema
Fluid Therapy: Fluid Fluid Therapy: Fluid ChallengeChallenge
Fluid challenge in patients with Fluid challenge in patients with suspected hypovolemia may be givensuspected hypovolemia may be given
500 - 1000 mL of crystalloids over 30 mins500 - 1000 mL of crystalloids over 30 mins 300 - 500 mL of colloids over 30 mins300 - 500 mL of colloids over 30 mins Repeat based on response and toleranceRepeat based on response and tolerance Input is greater than output due to Input is greater than output due to
venodilation and capillary leakvenodilation and capillary leak Most patients require continuing Most patients require continuing
aggressive fluid resuscitation during the aggressive fluid resuscitation during the first 24 hours of managementfirst 24 hours of management
VasopressorVasopressor
Initiate vasopressor therapy if fluid Initiate vasopressor therapy if fluid challenge fails to restore adequate challenge fails to restore adequate blood pressure and organ perfusionblood pressure and organ perfusion
Vasopressor therapy used Vasopressor therapy used transiently in face of life-transiently in face of life-threatening hypotension, even when threatening hypotension, even when fluid challenge is in progressfluid challenge is in progress
Vasopressor Vasopressor Norepinephrine or dopamine Norepinephrine or dopamine
first line agents to correct first line agents to correct hypotension in septic shockhypotension in septic shock
Norepinephrine more potent than Norepinephrine more potent than dopamine and more effective at dopamine and more effective at reversing hypotensionreversing hypotension
Dopamine particularly useful in Dopamine particularly useful in patients with compromised patients with compromised systolic function but causes more systolic function but causes more tachycardia and more tachycardia and more arrhythmogenicarrhythmogenic
VasopressorVasopressor Low dose dopamine should Low dose dopamine should not be used not be used
for renal protection in severe sepsisfor renal protection in severe sepsis An arterial catheter placed as soon as An arterial catheter placed as soon as
practical in all patients requiring practical in all patients requiring vasopressorsvasopressors
Arterial catheters provide more accurate Arterial catheters provide more accurate and reproducible measurement of and reproducible measurement of arterial pressure in shock states arterial pressure in shock states compared to a cuffcompared to a cuff
Vasopressin considered in refractory Vasopressin considered in refractory shock patients refractory to fluid shock patients refractory to fluid resuscitation and high dose vasopressorsresuscitation and high dose vasopressors
Infusion rate of 0.01-0.04 units/min in adultsInfusion rate of 0.01-0.04 units/min in adults May decrease stroke volumeMay decrease stroke volume
Inotropic TherapyInotropic Therapy
In patients with low cardiac output In patients with low cardiac output despite adequate fluid resuscitation, despite adequate fluid resuscitation,
dobutaminedobutamine may be used to may be used to increase cardiac outputincrease cardiac output
Combined with vasopressor therapy Combined with vasopressor therapy in hypotensionin hypotension
Steroids I.V corticosteroids recommended in I.V corticosteroids recommended in
patients with septic shock requiring patients with septic shock requiring vasopressors to maintain blood vasopressors to maintain blood pressurepressure
Administer i.v. hydrocortisone 200-300 Administer i.v. hydrocortisone 200-300 mg/day for 7 days in 3 or 4 divided mg/day for 7 days in 3 or 4 divided doses or by continuous infusiondoses or by continuous infusion
Reduces mortality rate in patients with Reduces mortality rate in patients with relative adrenal insufficiencyrelative adrenal insufficiency
In absence of shock, corticosteroids not In absence of shock, corticosteroids not be used for treatment of sepsisbe used for treatment of sepsis
Blood Product Blood Product AdministrationAdministration
Blood transfusion when Blood transfusion when hemoglobin decreases to < 7 g/dLhemoglobin decreases to < 7 g/dL
- Once tissue hypo-perfusion has Once tissue hypo-perfusion has resolved and in the absence of resolved and in the absence of significant coronary artery significant coronary artery disease, acute hemorrhage or disease, acute hemorrhage or lactic acidosislactic acidosis
- Target hemoglobin of 7 – 9 g/dLTarget hemoglobin of 7 – 9 g/dL
Blood Product Blood Product AdministrationAdministration
Erythropoietin not Erythropoietin not recommended for treatment of recommended for treatment of anemia associated with severe anemia associated with severe sepsissepsis
- Unless septic patients have - Unless septic patients have other accepted reasons for other accepted reasons for administration of erythropoietin administration of erythropoietin
Blood Product Blood Product AdministrationAdministration
Routine use of Routine use of fresh frozen fresh frozen plasmaplasma to correct laboratory to correct laboratory clotting abnormalities in absence of clotting abnormalities in absence of bleedingbleeding
Platelets administered when platelet Platelets administered when platelet counts are <5000/mmcounts are <5000/mm33 regardless of regardless of apparent bleedingapparent bleeding
Platelet transfusion when counts are Platelet transfusion when counts are 5000 - 30,000/mm5000 - 30,000/mm3 3 and significant and significant risk of bleedingrisk of bleeding
Platelet counts Platelet counts 50,000/ mm 50,000/ mm33 for for surgery or invasive proceduressurgery or invasive procedures
Glucose ControlGlucose Control
Following initial stabilization of Following initial stabilization of patients, maintain blood glucose patients, maintain blood glucose to < 150 mg/dLto < 150 mg/dL
Best results when blood glucose Best results when blood glucose maintained between 80 and 110 maintained between 80 and 110 mg/dlmg/dl
Glucose ControlGlucose Control Glycemic control strategy includes a Glycemic control strategy includes a
nutrition protocol with preferential nutrition protocol with preferential use of the enteral routeuse of the enteral route
Risk of hypoglycemia minimized Risk of hypoglycemia minimized by providing a continuous supply by providing a continuous supply of glucose substrate of glucose substrate
Accomplished by 5% or 10% Accomplished by 5% or 10% dextrose IV infusion ,followed by dextrose IV infusion ,followed by initiation of feeding preferably initiation of feeding preferably by enteral routeby enteral route
Renal ReplacementRenal Replacement
Continuous venovenous hemofiltration and intermittent hemodialysis considered equivalent in acute renal failure (in absence of hemodynamic instability)
Continuous hemofiltration offers Continuous hemofiltration offers easier management of fluid balance easier management of fluid balance in hemodynamically unstable in hemodynamically unstable patients patients
Bicarbonate TherapyBicarbonate Therapy Bicarbonate not recommended for
improving hemodynamics or reducing vasopressor requirements for hypoperfusion induced lactic acidemia with pH 7.15
No difference in vasopressor No difference in vasopressor requirements or hemodynamic requirements or hemodynamic variables between bicarbonate and variables between bicarbonate and normal saline for treating normal saline for treating hypoperfusion-induced acidemiahypoperfusion-induced acidemia
Effects of bicarbonate therapy at pH Effects of bicarbonate therapy at pH levels < 7.15 not studiedlevels < 7.15 not studied
DVT prophylaxisDVT prophylaxis DVT prophylaxis with low-dose
unfractionated heparin or low molecular weight heparin
Use mechanical prophylactic device Use mechanical prophylactic device or intermittent compression in or intermittent compression in patients with contraindications to patients with contraindications to heparinheparin
Use a combination of Use a combination of pharmacological and mechanical pharmacological and mechanical therapy in very high risk patients therapy in very high risk patients (eg, severe sepsis and history of (eg, severe sepsis and history of DVT)DVT)
Stress ulcer prophylaxisStress ulcer prophylaxis
Stress ulcer prophylaxis given to all patients with severe sepsis
H2 receptor blockers more H2 receptor blockers more efficacious than sucralfate efficacious than sucralfate and are preferred agents and are preferred agents
Proton pump inhibitorsProton pump inhibitors
Basics of managementBasics of management
Suspect sepsis if clinical signs presentSuspect sepsis if clinical signs present Resuscitation should be started Resuscitation should be started
immediately (fluids/pressors/steroid as immediately (fluids/pressors/steroid as indicated)indicated)
Identify source if possibleIdentify source if possible Baseline investigations and blood Baseline investigations and blood
cultureculture Start empirical antibiotics according to Start empirical antibiotics according to
center policycenter policy Close monitoring and periodic review Close monitoring and periodic review
are vital for successful outcome are vital for successful outcome
ConclusionConclusion Sepsis is a widespread problem in a Sepsis is a widespread problem in a
surgical set upsurgical set up Sepsis is reversible in early stagesSepsis is reversible in early stages Hence early detection and prompt Hence early detection and prompt
treatment necessarytreatment necessary High index of suspicion, active High index of suspicion, active
resuscitation and judicious use of resuscitation and judicious use of antibiotics, pressors etc are antibiotics, pressors etc are cornerstones of therapycornerstones of therapy
Antibiotic choice dictated by culture Antibiotic choice dictated by culture results. Empirical therapy is institution results. Empirical therapy is institution dependentdependent