Contents What you want need to know Key

Contents • What you want / need to know • Key points / Top tips • CVS cases

What you want / need to know • How to safely anaesthetise patients with CVS issues • How to resuscitate sick patients

Guideline details • • Clinical risk factors Risk assessment tools Investigations Pre-op revascularisation • Patients with stents • Pacemakers & defibrillators • Timing of drugs e. g. omit ACEI • Anaesthetic management

(1) Anaesthesia for elective surgery is generally safe!

Mortality 1: 200, 000

(2) Risk assessment and management

Factors to consider History / Examination / Investigations Patient / Anaesthetic / Surgical factors RISK

Framework 1 • Preoperative • Intraoperative • Postoperative Ø Induction Ø Maintenance Ø Emergence Functional Capacity / Reserve

Need > 4 METS for good oucome after major surgery

Anaerobic threshold (AT)

AT, IHD & mortality

Framework 2 • Recognise an emergency • Assess the patient • Priorities are ABC • Initiate resuscitation as appropriate

Cerebral circulation • CPP = MAP – ICP • CPP < 70 mm. Hg = poor outcomes • Clinically significant raised ICP = 20 mm. Hg • MAP of at least 90 mm. Hg

Prevent secondary injury: Hypoxia, BP, glucose, temperature *Single episode of hypotension doubles mortality*

(3) Utilise the equations for BP & CO

Cardiovascular physiology

Cardiovascular physiology • Blood pressure ≈ V • Cardiac output / Flow • Systemic vascular resistance ≈ R ≈ I

Cardiovascular physiology

Cardiovascular physiology • BP = CO x SVR • [CO = SV x HR] • BP = SV x HR X SVR

CVS effects of anaesthesia • Myocardial depression • Impaired baroreceptor reflex • Vasodilatation • BP = SV x HR x SVR

(4) Remember the Frank. Starling law

Frank-Starling curve

Frank-Starling curve

(5) Minimise all the periods of CVS instability

CVS case • 62 year old man • For an elective Lap Nissens • Known hypertensive • BP = 150/85 at GP surgery • BP on arrival = 175/99

Framework 1 • Preoperative • Intraoperative Ø Induction Ø Maintenance Ø Emergence • Postoperative

Countering the effects of anaesthesia • Fluids • Vasopressors • Inotropes • α 1 / α 2 / β 1 / β 2

CVS case • 62 year old man • For an elective Lap Nissens • Known hypertensive + stable angina • BP = 150/85 at GP surgery • BP on arrival = 175/99

Arterial line

Arterial line d. P/dt sv

Summary • Anaesthesia is generally safe, especially for elective surgery • Focus on assessing risk • Remember equations for BP & CO • Remember Frank-Starlings law • Aim to minimise all the periods of CVS instability

Thanks! Any questions