Resuscitating the Hypotensive

Patient Kane Guthrie FCENA

Hypotensive Resuscitation

•Look at shock

•Fluid resuscitation

•Pharmacology of vasoactive medications

•Current evidence

•Case Studies

Shock

Inadequate oxygen

delivery to meet tissue demands

Shock is a

time-dependantdisorder!

Epidemiology of Shock

Diagnosing Shock

3 components

•Systemic arterial hypotension

•Clinical signs tissue hypoperfusion

•Hyperlactatemia

Hypotension is Bad

Hypotension in ED

•Independently predicts in-hospital mortality

•Risk of death increases:

•SBP <80mmHg

•Sustained hypotension >60min

Hypotension Predicts Mortality

•Pulmonary Embolism

•Myocardial Infarction

•Traumatic Brain Injury

•Sepsis

Assessing the Shocked Patient

• Physical exam can assess overall tissue perfusion:

• Assess mental status

• Are patients confused?, dizzy?, drowsy?

• Assess skin

• Is the skin cool or mottled?

• Assess kidney perfusion

• Is urine output less than 0.5 mL/kg/hour?

Laboratory Assessment

• Laboratory testing can be used to assess perfusion:

• Elevated serum creatinine

• This signifies reduced organ perfusion

• Elevated liver function tests

• This signifies reduced organ perfusion

• Oxygen saturation of venous blood

• SVO2

Checking Lactate

•Marker end organ perfusion

•End product – anaerobic metabolism

•Lactate >4 = panic value

•Lactate normalisation

Using CVP

•Poor evidence behind recommendations

•8-12mmHg is ideal range

•>15 mmHg if ventilated

•<8mmHg & hypotensive = fluids

Measuring IVC

Full non-collapsing IVC = Pt adequately filled.

Fill the Tank

Fluid Resuscitation

•Improve microvascular blood flow

•Increase cardiac output

•May benefit cardiogenic shock

•Fluid maldistribution

What fluid & How Much?

•Crystalloid –first choice

•Albumin in certain patients!

•Boluses 500ml-1tre every 20-30mins

Monitoring Fluid Resuscitation

•^ systemic arterial pressure

•< heart rate

•^ urine output

When Fluids Fail

Vasoactive Agents

•Used to optimise:

•End-organ perfusion

•Oxygen delivery

Inotrope(s)

•Increase the force & velocity of myocardial contraction with increased contraction, stroke volume & cardiac output.

Inotropes

•Examples:

•Adrenaline

•Dobutamine

•Isoprenaline

Vasopressor(s)

•Increase vascular tone with raised MAP & SVR.

Vasopressor(s)

•Noradrenaline

•Vasopressin

•Dopamine

Push Dose Pressor

•Short acting vasopressor that works through potent & selective alpha stimulation.

Push Dose Pressor

•Metaraminol

•Adrenaline

•Ephedrine

The Hard Evidence!

•No agent has shown to have superiority over any others in good quality studies!

Use Based On

•Cost

•Availability

•Interpretation of physiology

•Personal/physician preference

•Institutional preference

Target Receptors

•Alpha 1- vasoconstriction, ^ SVR

•Alpha 2 – smooth muscle contraction

•Beta 1 – positive chronotrope/inotrope, ^HR, ^contractility

•Beta 2 – induce vasodilatation

CVC

•Preferred

•IVC till bridge to CVC

Do We Always Need CVC?

Indications

•Fluid resuscitation = failed

•Persistent hypotension

•Improve contractility & cardiac output

Invasive Monitoring

Forget BP –Focus MAP

•Mean arterial pressure

MAP = CO x SVR

•Target MAP >65mmHg

•Chronic hypertension aim higher

•Measure adequate tissue perfusion

Case 1

Case 1

•What vasoactive medication is indicated?

Adrenaline

•Alpha & beta adrenergic properties

•Treats 3 aspects of anaphylaxis

•Laryngeal oedema

•Bronchospasm

•Shock

Adrenaline Actions

•Vasoconstriction

•Reduction - mucosal oedema

•Bronchodilation

•Increased myocardial contractility

Case 1

•What dose and route would you give it?

Case 1

•Adult 0.3-0.5mg (1mg/ml)

•IMI (lateral thigh)

•Rpt as needed - consider infusion.

Case 2

Case 2

•What vasoactive medication is indicated?

Noradrenaline

•Surviving Sepsis Guidelines 2013

•Norad = vasoconstriction - HR + contractility.

•6mg 100mls or 3mg 50mls 5% Dextrose

Vasoactive's in Sepsis

Case 3

Postintubation Hypotension

•Occurs in 23% of ED intubations

•Vasodilation of induction agents

Case 3

•What vasoactive medication is indicated?

Push Dose Pressors

•Metaraminol 10mg/ml (mix in 20mls)

•Sympathomimetic amine

• increases systolic/diastolic BP

•Short acting 3-10min

Case 4

Cardiogenic Shock

•Results from primary cardiac dysfunction

•MI

•papillary muscle/ventricular septal rupture, left ventricle dysfunction

Case 4

•What vasoactive medication is indicated?

Inotropes

•Dobutamine

•Beta 1 effects - cardiac contractility

•Beta 2 effects - reduce afterload

•Refractory consider adding Noradrenaline

Take Home Points

•Shock/hypotension is common

•Fluids often fail

•Be familiar with indications, dose & pharmacology for vasoactive meds

Thankyou