Anaesthetics- Fundamentals of Anaesthetic Curriculum Flashcards
What are the different peri-operative risk scoring systems?
ASA and POSSUM.
What is the ASA peri-operative risk scoring system?
ASA 1: healthy patient.
ASA 2: mild systemic disease; no functional limitation.
ASA 3: moderate systemic disease; have functional limitation.
ASA 4: severe systemic disease that is a constant threat to life.
ASA 5: moribund patient; unlikely to survive 24hrs, with or without treatment. Postscript E: indicates emergency surgery.
What is POSSUM scoring?
Risk prediction.
Enter patient physiological and operative variables.
Mortality and morbidity risk:
pre-operative = risk discussion
peri-operative = need for invasive monitoring?; post-operative = over 5% mortality risk should go to HDU/ITU post-operative.
Why is there a nil by mouth policy before surgery, and what is the usual guidance?
Reduce aspiration risk. Food: 6hrs; water: 2hrs; caveat: reflux, obesity, slow gastric transit e.g. trauma.
How do you prescribe opioids, e.g. morphine?
Dose
Form- oral/IV/subcut/IM
Strength (where appropriate)
Total quantity or dosage units of the preparation in words and figures- total amount that the patient will take away
For instalment prescriptions, specify the instalment amount and instalment interval.
Handwritten.
Your signature and date (include bleep no.)
List 5 anti-emetic drugs.
Ondansetron
Cyclizine
Dexamethasone
Metoclopramide
Prochlorperazine
What is the mechanism of action, dose, route, and side effects of ondansetron?
Mechanism of action = 5HT3R antagonist. Side effects = bradycardia; long QT syndrome. Dose/route = 4-8mg TDS; PO/IV.
What is the mechanism of action, dose, route, and side effects of cyclizine?
[*not in lecture but in previous flashcards]
Mechanism of action = H1 R antagonist. Side effects = tachycardia; anti-cholinergic. Dose/route = 50mg TDS; PO/slow IV/IM.
What is the mechanism of action, dose, route, and side effects of dexamethasone?
[*not in lecture but in previous flashcards]
Mechanism of action = corticosteroid. Side effects = hyperglycaemia; perineal ‘burning’ (transient). Dose/route = 4-8mg BD; IV.
What is the mechanism of action, dose, route, and side effects of metoclopramide?
[*not in lecture but in previous flashcards]
Mechanism of action = central DA2 R antagonist. Side effects = extrapyramidal. Dose/route = 10mg TDS; PO/IV.
What is the mechanism of action, dose, route, and side effects of prochlorperazine?
[*not in lecture but in previous flashcards]
Mechanism of action = DA antagonist. Side effects = extrapyramidal; long QT syndrome. Dose/route = 12.5mg BD; IM.
Explain the WHO pain ladder.
Step 1: non-opioid, e.g. aspirin, paracetamol, or NSAID, ±adjuvant.
Step 2: weak opioid, for mild to moderate pain, e.g. codeine, ±non-opioid, ±adjuvant. [side effects- nausea, constipation]
Step 3: strong opioid, for moderate to severe pain, e.g. morphine, ±non-opioid, ±adjuvant. {oral morphine first, then push button to administer morphine]
Case 1: a poorly controlled asthmatic patient on oral steroids presents for emergency manipulation of a fractured radius, he is slightly breathless and wheezy at rest, describe your management.
Management of severe bronchospasm outside of theatre: - BTS guidelines
A,B,C.
O2: start high flow oxygen and gain IV access.
Salbutamol nebuliser 2.5-5mg.
Hydrocortisone 100mg IV 6-hourly or prednisolone orally 40-50mg/day.
Ipratropium nebuliser 0.5mg 4-6-hourly; IV salbutamol if not responding (250mcg slow bolus then 5-20mcg/min).
Theophylline/aminophylline- [aminophylline less commonly used b/c narrow therapeutic window- death if given too quickly]
Magnesium 2g IV over 20 minutes.
In extremis (decreasing conscious level or exhaustion), adrenaline may be used: nebuliser 5ml of 1 in 1,000; senior clinician only: IV 10mcg (0.1ml 1:10,000) increasing to 100mcg (1ml 1:10,0000) depending on response.
What are the triggers of anaphylaxis?
Stings (wasp, bee, etc.)
Nuts
Food, e.g. milk, fish, chickpea, crustacean, etc.
Antibiotics, e.g. penicillin, cephalosporin
Anaesthetic drugs, e.g. suxamethonium, vecuronium
Other drugs, e.g. NSAID, ACEi, gelatins
Contrast media, e.g. iodinated Other, e.g. latex, hair dye, hydatid
How is anaphylaxis recognised?
ABCDE approach.
Airway problems:
- airway swelling, e.g. throat and tongue swelling (pharyngeal/laryngeal oedema);
- difficulty breathing and swallowing
- hoarse voice
- stridor (high pitched inspiratory noise caused by upper airway obstruction).
Breathing problems:
- shortness of breath
- increased respiratory rate
- wheeze
- tired
- confusion caused by hypoxia
- cyanosis (appears blue), usually a late sign
- respiratory arrest
Circulation problems:
- signs of shock- pale, clammy
- increased pulse rate (tachycardia)
- low blood pressure (hypotension)
- feeling faint, dizzy, collapse, decreased conscious level or loss of consciousness
- myocardial ischaemia and ECG changes even in individuals with normal coronary arteries
- cardiac arrest.
Disability.
Exposure
- Rash
- Swelling - angioedema
How is anaphylaxis managed?
Call for help.
Lie patient flat. Raise patient’s legs.
Adrenaline.
When skills and equipment available:
- establish airway
- high flow oxygen
- IV fluid challenge
- IV chlorphenamine
- IV hydrocortisone
Monitor: -pulse oximetry, ECG, BP
What are the triggers for giving a blood transfusion?
Hb: >90
How to assess and manage comorbidities perioperatively?
Diabetes
IHD
Asthma
COPD
Anticoagulants
Sickle cell
Disease optimisation and control
What criteria allows a surgery to be a day surgery procedure [go home the same day, hospital stay of max 24 hr?]
Social- carer at home, good home setup, patient willing
Medical- fit enough to go home, comorbidities, obesity, stable chronic disease
Surgical- what are the risks of complications, can post op symptoms be controlled at home, will pt be mobile after surgery
What is the Mallampati score?
Measures airway access
High predictor for difficult airway, along with neck movement
Stage 1 best, Stage 4 worst
Stage 1: Can see soft palate clearly + whole uvula
Stage 2: Can see whole uvula, but not soft palate
Stage 3: Can see base of uvula
Stage 4: Can’t see uvula at all
What are the types of airway adjuncts and devices?
When are they used and what are their parts?
- Oropharyngeal airway
- get tongue out of way so opens airway + bag mask can work more easily
How do you choose correct size of oropharyngeal airway?
Corner of mouth to angle of mandible
- Bag mask valve
- only use in apneic patient= not breathing at all
- Parts: Facemask, valve, compression chamber, oxygen reservoir]
Connect to oxygen outlet + ensure outlet is on high flow- can provide 99-100% O2
- Supraglottic airway
Sits at level of vocal cords- just above
Not definitive airway
- Endotracheal tube
Parts- cuff [balloon that inflates- goes inside trachea]
- black line- level of vocal cords- so doesn’t end up in bronchiole
Pilot balloon that inflates cuff- by putting air in
Can connect other end to bag mask valve or other equipment
Definitive airway
WHO checklist
Reduces surgical mortality by 40%
What needs to be considered for VTE prophylaxis?
What would you do to mitigate risk?
Mobility
Risk factors
Bleeding risk
Summary of anti emetic drugs- table
What does this show?
How would you treat it?
Tension pneumothorax
Needle aspiration
[Acute b/c tension obliterated venous return]
