ShockShock

Year 4 TutorialsYear 4 Tutorials

A B A B C C D ED E

Objectives:Objectives:

What is shock?What is shock?

Types of shockTypes of shock

Management principlesManagement principles

Shock Definition:Shock Definition:

State of inadequate tissue perfusion and tissue State of inadequate tissue perfusion and tissue oxygenation as a result of a deficiency in the oxygenation as a result of a deficiency in the

circulationcirculation

Types of Shock:Types of Shock:

Distributive – SepticDistributive – Septic

AnaphylacticAnaphylactic

NeurogenicNeurogenic CardiogenicCardiogenic Obstructive –Obstructive – Tension pneumothorax Tension pneumothorax

Cardiac tamponadeCardiac tamponade HypovolaemicHypovolaemic

BP = CO x SVRBP = CO x SVR

HR x SVHR x SVNormal vascular tone

determined by sympathetic innervation

•Contractility•Preload (ventricle stretch)•Afterload

CARDIAC PHYSIOLOGY

Distributive - SepsisDistributive - Sepsis

SIRS = 2 of SIRS = 2 of RR > 20 breaths per minute RR > 20 breaths per minute WCC < 4 or > 12 WCC < 4 or > 12 Heart rate > 90 beats per minute Heart rate > 90 beats per minute Temperature: Fever > 38.0 °C or < 36.0 °CTemperature: Fever > 38.0 °C or < 36.0 °C

Sepsis = SIRS + Evidence of infectionSepsis = SIRS + Evidence of infection

Distributive - SepticDistributive - Septic

Massive vasodilationMassive vasodilation BP = CO x BP = CO x SVR ( )SVR ( )

Often dehydratedOften dehydrated

Fluids & antibiotics, Fluids & antibiotics,

Vasoconstrictors.Vasoconstrictors.

Distributive - AnaphylaxisDistributive - Anaphylaxis

Massive vasodilationMassive vasodilation

Type 1 hypersensitivityType 1 hypersensitivity

Treatment:Treatment: Fluids, adrenaline, Fluids, adrenaline,

chlorphenamine, steroidschlorphenamine, steroids ?Anaesthetist?Anaesthetist

Distributive - Neurogenic Distributive - Neurogenic

Massive vasodilationMassive vasodilation

Loss of sympathetic Loss of sympathetic vascular tone.vascular tone.

Fluids and Fluids and vasoconstrictors.vasoconstrictors.

Cardiogenic shockCardiogenic shock

PUMP failure!PUMP failure! Cannot empty pumpCannot empty pump

BP = BP = CO CO x SVRx SVR

CO = CO = HRHR x x SVSV ( contractility)( contractility)

Causes:Causes: Acute MIAcute MI

Large InfarctionLarge Infarction Papillary muscle rupturePapillary muscle rupture

Other ConditionsOther Conditions Septic shockSeptic shock MyocarditisMyocarditis Arrhythmias Arrhythmias Drugs – eg beta-blocker Drugs – eg beta-blocker

overdoseoverdose Myocardial contusionMyocardial contusion

Cardiogenic shockCardiogenic shock

Treat underlying Treat underlying cause if possiblecause if possible

Inotropes.Inotropes. Balloon pumpBalloon pump

Obstructive –Tension PneumothoraxObstructive –Tension Pneumothorax

Accumulation of air Accumulation of air under pressure in the under pressure in the pleural space. pleural space.

1-way valve1-way valve

Mediastinal shift: Mediastinal shift: preload & afterload = preload & afterload = SV SV

Obstructive –Tension PneumothoraxObstructive –Tension Pneumothorax

Treatment:Treatment: Needle decompressionNeedle decompression Chest drainChest drain

Obstructive – Cardiac Tamponade Obstructive – Cardiac Tamponade

Accumulation of fluid in Accumulation of fluid in the pericardial space, the pericardial space, resulting in reduced resulting in reduced ventricular fillingventricular filling

Rapid filling of only 150ml Rapid filling of only 150ml causes compromisecauses compromise

Obstructive – Cardiac Tamponade Obstructive – Cardiac Tamponade

Becks triad:Becks triad: increased jugular venous increased jugular venous

pressure, pressure, hypotension hypotension diminished heart sounds.diminished heart sounds.

Treatment: needle Treatment: needle pericardiocentesispericardiocentesis

Hypovolaemic ShockHypovolaemic Shock

The system is DRY.The system is DRY. Causes:Causes:

HaemorrhageHaemorrhage SepsisSepsis D&VD&V

BP = BP = COCO x SVR x SVR CO = HR x CO = HR x SVSV

Hypovolaemic / HaemorrhagicHypovolaemic / Haemorrhagic

Where is the Blood?Where is the Blood?

RevealedRevealed On the floor, at the sceneOn the floor, at the scene

ConcealedConcealed ChestChest Peritoneal/PelvisPeritoneal/Pelvis Long bonesLong bones RetroperitoneumRetroperitoneum

Hypvolaemic shock management:Hypvolaemic shock management:

Treat underlying cause Treat underlying cause haemorrhage control – 1haemorrhage control – 1stst aid, angio, theatre aid, angio, theatre

Venous access / fluidsVenous access / fluids

Fluid replacementFluid replacement

Vascular access:Vascular access:

TWO TWO large venflonslarge venflons

Where? Where? Anticubital fossaAnticubital fossa

Consider IOConsider IO Take samples – X-matchTake samples – X-match

Initial fluid therapy:Initial fluid therapy:

CrystalloidCrystalloid

ColloidColloid

Consider warmingConsider warming

Cross matchedCross matched

Type specificType specific

‘‘O’ negativeO’ negative

Massive transfusion Massive transfusion protocolprotocol

Response to fluid treatment:Response to fluid treatment:

General General

Urine - 30ml / hour (0.5mg/kg)Urine - 30ml / hour (0.5mg/kg)

Acid / Base balance (lactic acidosis)Acid / Base balance (lactic acidosis)

Shock summaryShock summary

Distributive – Distributive – vasodilation - reduced vasodilation - reduced

SVRSVR

Cardiogenic – Cardiogenic – reduced heart rate / reduced heart rate /

stroke volume - pump stroke volume - pump failurefailure

Obstructive – Obstructive – reduced stroke reduced stroke

volume – blood canvolume – blood can’’t t get in or outget in or out

Hypovolaemic –Hypovolaemic – reduced stroke reduced stroke

volume - lack of blood volume - lack of blood volumevolume

May be a combination

Shock summaryShock summary

ABCsABCs Assess degree and causeAssess degree and cause Intervene: Intervene:

Treat underlying causeTreat underlying cause Maintain CO and SVR - fluids, vasocostictors, Maintain CO and SVR - fluids, vasocostictors,

inotropesinotropes ReassessReassess Get HELPGet HELP

QuestionsQuestions

??A&E Department, Aberdeen Royal Infirmary

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