Wk 2 Flashcards
What is anaesthesia
Implies a pt is unconscious and all sensation is lost
Types of anaesthesia
General: reversible, unconscious state, affects CNS, characterised by amnesia (sleep), analgesia (freedom form pain),depression of reflexes, muscle relaxation
Regional: loss of sensation to specific area or region of the body I.e. Spinal, epidural
Local: administered to one part of the body by local infiltration, purposely blocks nerve fibre in and around operative site
Premedication to surgery
Sedative Narcotics Anticholinergics Anti emetics To decrease anxiety,bronchial secretions Analgesia Amnesia
Describe action of sedative and give example
Sedate
Amnesia
Calm/hypnotic state
E.g. Benzodiazepines which include Valium and midazolam (amnesia, decrease anxiety and fear), barbiturates (sleeping pills, prolonged sedative state, assists with sleep)
Describe action of narcotics and give example
Raise pain threshold
Lower metabolic rate
Decrease amount of anaesthetic required
E.g. Morphine (useful for pt already in pain, prolonged action), fentanyl (short acting, IV admin immediately before induction)
Action of Anticholinergics and example
Interfere with stimulation of vagus nerve
Increase HR
Decrease oral and respiratory secretions
Prevent vagal mediated hypotension, cardiac arrhythmia and bradycardia
E.g. Atropine sulfate, gycopyrrolate
What is the action of Antiemetic and examples
Minimise nausea and vomiting
E.g. Phenergan, droperidol, ondansetron
Process of general anaesthesia
Arrive in OR
Pt identified/consent/lab test reviewed
Monitoring connected
Iv access
Pt preoxygenated with 100% O2 for 3-5mins
Opioids and benzodiazepines administered
1. Induction: administer anaesthesia agents until pt is ready for positioning or surgical prepping
2. Maintenance: from this point until near completion
3. Emergence: pt begins to emerge and pt is ready to leave OR
4. Recovery
Inhalation agents of anaesthesia
Nitrous oxide: poor relaxation, minimal nausea and vomiting, increased vol in air pockets
Halothane: non-irritant, little muscle relaxation, potentially toxic to liver, raises ICP
Enflurane: some muscle relaxation, cardiac stability, don’t take if renal disease
Isoflurane: low organ toxicity, expensive, potent muscle relaxation
Thiopentone: short acting, depresses myocardium
Propofol: short half life, hypotension, irritation at injection site
Types of muscle relaxants
Depolarising: (suxamethanonium) last 5mins, acts in seconds
No depolarising: (vecuronium) acts over 2-3mins, lasts 30-60mins
What is used in intubation
LMA: laryngeal mask airway, inserted without muscle relaxant, posited over larynx and inflated
ETT: endoctracheal tube, women size 8, males 8.5, 7.5mm, ventilation and aspiration, position head (neck flexed, sniffing air, head in straight line)
Laryngoscopes
Used to intubate
Consists of a blade (size 1-4), with fibre optic light and handle
Blade is curved
Children blade is straight
Pre-op checklist
- Pre-op nurse verifies info: consent, correct pt, correct procedure, correct side, side marked by pt, correct time
- Pt states name DOB, procedure
- Mandatory examination results
- Allergies
- Patient property/personal effects
- Periop fasting
- Meds to be administered
- Bowel prep completed
Rapid sequence induction
Fats intubation in emergency Obese pt Cricoid pressure to prevent aspiration Digital pressure applied to cartilage Prevents regurgitation and aspiration (close oesophagus behind it) Released when ETT cuff is inflated
Aspiration
Decreased throat reflex
Acidic gastric contents enter lungs
Impede lung function and gas exchange
Aim to maintain pt’s state during analgesia
Oxygenate Unconsciousness Analgesia Muscle relaxation Control autonomic reflexes
The anaesthetic machine
Delivers o2 and anaesthetic gas mix
Mechanical ventilator
Source of gas
Reservoir bag
Monitors: ECG, BP, inspired o2, end tidal o2
Alarms: apnoea, breathing circuit disconnected
Daily checking procedure
What occurs during emergence
Recovery of pharyngeal and laryngeal reflexes
Extubation delayed until spontaneous respiration confirmed
Auctioning and oxygenation
Warm blankets
Asepsis
Without infection
Absence of micro-organisms that cause infection
Aseptic technique
Microbial contamination is prevented in the environment
Reduce exposure to potentially infectious blood and tissue
Every effort is to minimise and control the microorganism
Handwashing/surgical scrub
Maintain sterile field
Safe operative technique
Barriers
Client prep
Principles of asepsis
People must wear sterile gown and gloves and only touch sterile items
Unsterile personnel must touch unsterile items
Sterile drapes must be used
Items in sterile field must be sterile
Anything below waists or table level is unsterile
Items to be opened, dispensed and transferred in a sterile way
Must be monitored and never left unattended
Move around the sterile field carefully
Don’t lean across or walk between sterile fields
Creating a sterile field
Placing sterile towels/drapes around procedure site and stand that will hold sterile instruments
Pt is centre of field
Skin prep clean to dirty
Reusable/disposable drapes
Principles of applying drapes
Time and space Handle as little as possible Carry folded drape to operation site Hold above waist level No flip, fan or shake Don't reach across the unsterile area Non perforating towel clips
What is strike through
Liquids soak through a barrier from sterile to unsterile area and vice versa
Passage of organisms through the barrier
Sometimes dry and not noticeable so look for stains
Steps to maintain a safe environment
Limit number of people in and out
Limit talking
Close door and curtains
Enclose areas to minimise dust and insects
Air condition room
Clean and disinfect surfaces between pt’s
Surgical conscience
Inner morality system and professional honesty which allows no compromise in practice
