Upload
victor-atkinson
View
218
Download
2
Tags:
Embed Size (px)
Citation preview
Hypovolemic Hypovolemic ShockShock
General Surgery OrientationGeneral Surgery OrientationMedical Student Lecture SeriesMedical Student Lecture Series
Juan Duchesne MD,FACS,FCCP,FCCMJuan Duchesne MD,FACS,FCCP,FCCM
ShockShock HypovolemicHypovolemic
SepticSeptic
Cardiogenic (Obstructive)Cardiogenic (Obstructive)
NeurogenicNeurogenic
AdrenalAdrenal
ShockShockMost common forms in surgery:Most common forms in surgery:
HypovolemicHypovolemic
SepticSeptic
CardiogenicCardiogenic
Hypovolemic ShockHypovolemic ShockDefinition:Definition:Reduction in intravascular volume leading Reduction in intravascular volume leading
to insufficient oxygen delivery to cells to insufficient oxygen delivery to cells (mitochondria)(mitochondria)
Hypovolemic ShockHypovolemic ShockReduced intravascular volume?Reduced intravascular volume?
No oxygen delivery! No oxygen delivery!
No aerobic metabolism! No aerobic metabolism!
Then…Then… Metabolic acidosis (lactic acid production)Metabolic acidosis (lactic acid production) Endoplasmic recticulum swellingEndoplasmic recticulum swelling Mitochondrial damageMitochondrial damage Cell Death!Cell Death!
Hypovolemic ShockHypovolemic ShockVascular compartments:Vascular compartments:
TBW (60% of IBW)TBW (60% of IBW) Total Body WaterTotal Body Water
ICW (40%)ICW (40%) ECW (20%)ECW (20%) Intracellular WaterIntracellular Water Extracellular Extracellular
WaterWater
InterstitiumInterstitium PlasmaPlasma(1/3)(1/3) (2/3)(2/3)
Hypovolemic ShockHypovolemic ShockLoss of circulating blood volume (Plasma)Loss of circulating blood volume (Plasma)
Normal Blood Volume:Normal Blood Volume:
- 7% IBW in adults- 7% IBW in adults
- 9% IBW in kids- 9% IBW in kids
Hypovolemic ShockHypovolemic Shock
Tension Tension Pneumothorax Pneumothorax ~ impairment ~ impairment of ventricular of ventricular filling.filling.
Hypovolemic ShockHypovolemic ShockHemorrhagic shock (3 categories)Hemorrhagic shock (3 categories)
Compensated:Compensated:– 0-20% of blood loss0-20% of blood loss
– Blood pressure is maintained via increased Blood pressure is maintained via increased vascular tone and increased blood flow to vital vascular tone and increased blood flow to vital organsorgans
HypovolemicHypovolemic ShockShockThe body’s response:The body’s response:
Compensated shock Baroreceptor mediated Compensated shock Baroreceptor mediated vasoconstriction!vasoconstriction!
Increased epinephrine, vasopressin, angiotensinIncreased epinephrine, vasopressin, angiotensin Results in:Results in:
– TachycardiaTachycardia– TachypneaTachypnea– Lowered pulse pressureLowered pulse pressure– Slightly lowered urine outputSlightly lowered urine output
Hypovolemic ShockHypovolemic ShockThe Organs who win:The Organs who win: BrainBrain HeartHeart KidneysKidneys LiverLiver
The Organs who lose:The Organs who lose: SkinSkin GI tractGI tract Skeletal MuscleSkeletal Muscle
HypovolemicHypovolemic ShockShockBut whyBut why
The body will make whatever adjustsments it can to The body will make whatever adjustsments it can to maintain….maintain….
AdequateAdequate CardiacCardiac
OutputOutput
Brain and heart perfusions remain Brain and heart perfusions remain near normalnear normal while while other less critical organ systems are, in proportion to the other less critical organ systems are, in proportion to the blood volume deficit, stressed by ischemia.blood volume deficit, stressed by ischemia.
Hypovolemic ShockHypovolemic ShockUncompensated:Uncompensated:
20-40% loss of blood volume20-40% loss of blood volume
Decrease in BPDecrease in BP
TachycardiaTachycardia
HypovolemicHypovolemic ShockShockThe body’s responseThe body’s response
Uncompensated shockUncompensated shock The intravascular volume deficit exceeds the The intravascular volume deficit exceeds the
capacity of vasoconstrictive mechanisms to capacity of vasoconstrictive mechanisms to maintain systemic perfusion pressure.maintain systemic perfusion pressure.
Increased cardiac outputIncreased cardiac output Increased respirationIncreased respiration Sodium retentionSodium retention
Hypovolemic ShockHypovolemic ShockLethal exsanguination:Lethal exsanguination:
40% loss of blood volume40% loss of blood volume
Profound hypotension and inability to Profound hypotension and inability to perfuse vital organsperfuse vital organs
Hypovolemic ShockHypovolemic ShockThe body’s responseThe body’s response
Lethal exsanguination:Lethal exsanguination:– ObtundedObtunded– Severe hypotensionSevere hypotension– Severe tachycardiaSevere tachycardia– Cold, ClammyCold, Clammy– DeathDeath
Hypovolemic ShockHypovolemic ShockCaveats…Caveats…
AthletesAthletesPregnancyPregnancyExtremes of ageExtremes of ageMedicationsMedicationsHematocrit/HemoglobinHematocrit/Hemoglobin
HypovolemicHypovolemic ShockShockManagement:Management:
ABCs of trauma (AIRWAY is ABCs of trauma (AIRWAY is always first!)always first!)
Control hemorrhage (splint the Control hemorrhage (splint the limb!!)limb!!)
Obtain IV access and resuscitate Obtain IV access and resuscitate with fluids and blood with fluids and blood
– 2 liters crystalloid for adults2 liters crystalloid for adults– 20 cc/kg crystalloid x 2 for kids20 cc/kg crystalloid x 2 for kids
Blood vs. Crystalloid??Blood vs. Crystalloid??
Long term critical care Long term critical care managementmanagement
Hypovolemic ShockHypovolemic Shock
Your management goals AFTER securing the Your management goals AFTER securing the ABCs:ABCs:
STOP THE BLEEDING!STOP THE BLEEDING!
RESTORE VOLUME!RESTORE VOLUME!
CORRECT ANY ELECTROLYTE/ACID-BASE CORRECT ANY ELECTROLYTE/ACID-BASE DISTURBANCES!DISTURBANCES!
Hypovolemic ShockHypovolemic Shock
this requires a trip to the OR…this requires a trip to the OR…
Hypovolemic ShockHypovolemic ShockAnd sometimes the ED becomes the ORAnd sometimes the ED becomes the OR
Hypovolemic ShockHypovolemic ShockVolume Resuscitation ~ What are my goals?Volume Resuscitation ~ What are my goals?
Rapid ResponderRapid Responder– Give 500cc-1 Liter crystalloid Give 500cc-1 Liter crystalloid rapid rapid
improvement of BP/HR/Urine outputimprovement of BP/HR/Urine output– < 20% blood loss< 20% blood loss– Surgery consultSurgery consult
Hypovolemic ShockHypovolemic ShockVolume Resuscitation ~ What are my goals?Volume Resuscitation ~ What are my goals?
Transient ResponderTransient Responder– Give 500cc-1 Liter crystalloid Give 500cc-1 Liter crystalloid improves improves
briefly then deterioratesbriefly then deteriorates– 20-40% blood loss20-40% blood loss– Continue crystalloid infusion +/- BloodContinue crystalloid infusion +/- Blood– Surgery consultSurgery consult
Hypovolemic ShockHypovolemic ShockVolume Resuscitation ~ What are my goals?Volume Resuscitation ~ What are my goals?
Non ResponderNon Responder– Give 2 Liters crystalloid/ 2 units Blood Give 2 Liters crystalloid/ 2 units Blood no no
responseresponse– > 40% blood loss> 40% blood loss– STAT Surgery consult!STAT Surgery consult!
Hypovolemic ShockHypovolemic ShockIs my volume resuscitation Is my volume resuscitation
adequate/inadequate?adequate/inadequate?
Urine output Urine output Vital signsVital signsSkin perfusionSkin perfusionPulse OximetryPulse OximetryAcidemia??Acidemia??
Septic ShockSeptic ShockAn exaggerated endogenous inflammatory An exaggerated endogenous inflammatory
response to invasive infection leading to:response to invasive infection leading to:
circulatory collapsecirculatory collapse multiple organ failuremultiple organ failure deathdeath
Septic ShockSeptic Shock
Septic ShockSeptic ShockMortalityMortalityover 35% (sepsis with hypotension)over 35% (sepsis with hypotension)
45% (sustained septic shock)45% (sustained septic shock)
SepticSeptic ShockShockManagement:Management: Identify and treat the infectious sourceIdentify and treat the infectious source
eg – simple incision & drainage? eg – simple incision & drainage? Exploratory laparotomy?Exploratory laparotomy?
Amputation?Amputation?
Volume resuscitationVolume resuscitation
Restoration of perfusion pressure (may need Restoration of perfusion pressure (may need pressors!)pressors!)
Cardiogenic ShockCardiogenic ShockAcute hypotensionAcute hypotension
low cardiac output low cardiac output
inadequate LV outflow inadequate LV outflow
Poor end organ perfusion!Poor end organ perfusion!
Cardiogenic ShockCardiogenic ShockCauses most likely to see on the surgery wards:Causes most likely to see on the surgery wards:
Acute MIAcute MI Arrhythmia (A. fib)Arrhythmia (A. fib) Cardiac Contusion Cardiac Contusion Cardiac TamponadeCardiac Tamponade Massive Pulmonary EmbolismMassive Pulmonary Embolism Decompensated Congestive Heart FailureDecompensated Congestive Heart Failure
ShockShock
??