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Flashcards in Anaesthesia and Cardiovascular Disease Deck (10)
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Anaesthesia and Cardiovascular Disease

A. Hypertension
B. Ischemic Heart Disease
C. Valvular Heart Disease
D. Cardiac Failure
E. Dysrhythmias


Effect of anaesthesia on hypertension

Hypertensive crises with potent stimuli:
Laryngoscopy and intubation
Surgical stimulation
Increased sensitivity to vasodilatation of anaesthetic agents  hypotension
Often volume depleted and tolerate fluid or blood loss poorly
Low cardiac output may compromise organ perfusion
Anti-hypertensive drugs affect anaesthesia


Interactions of hypertensive medication

Fluid depletion and electrolyte disturbances (esp K)
B-blockers: Bradycardia/ negatively inotropic
Ca2+ blockers: hypotension
ACE inhibitors (exaggerated hypotension GA)
Irritable airways


Hypertension risk evaluation

Treated and well-controlled hypertensives= normal anaesthetic risk
Treated, uncontrolled patients= higher risk
Untreated, uncontrolled patients= have the highest risk
Diastolic BP >120 for elective surgery= BP control =>Postpone for 2 - 6 weeks


Assessing the hypertensive patient

BP chart with regular BP recordings (trend)
Effort tolerance
Effort tolerance
ECG and CXR to assess cardiac hypertrophy


Principles of Management

Optimise BP control if time allows
CONTINUE anti-hypertensive therapy
Good premed to minimise anxiety
Blunt the intubation response
Avoid ≥25% ↓ in Systolic / Mean BP
Adequate post-op analgesia


Ischaemic heart disease

Major cause of peri-operative deaths
Anaesthesia may aggravate or precipitate acute coronary syndrome
Peri-operative myocardial infarction has a
± 50% mortality


IHD Risk Evaluation

Acute coronary syndrome (unstable angina + myocardial infarction) is an extremely high anaesthetic risk
Patients with “stable angina” AND RECENT MI < 6MONTHS) and poor effort tolerance: elevated risk
Good effort tolerance (>2 flights of stairs) normal risk


Peri-operative management (IHD)

Good Premed
Maintain Cardiovascular i.e. slow rate and good diastolic pressure.
Monitor ST segment; 5-lead ECG; consider invasive arterial line
Appropriate Agent selection:
Etiomidate (propofol slowly and cautiously)
Acceptable volatiles: Isoflurane, sevoflurane
ALL muscle relaxants
Good analgesia
Fentanyl gold standard; morphine acceptable
Consider: LA or regional techniques
IV paracetamol
Careful with NSAIDs


Post-operative Placement

Most peri-operative myocardial infarcts occur in the first 48-72 hours following surgery
Need good monitoring and analgesia post-operatively, and supplemental oxygen if needed