Anaesthetics - Conduct of general anaesthesia Flashcards
what is the process of anaesthesia?
pro-op assessment > preparation > induction > maintenance > emergance > recovery > post-op care and pain management
what is involved in preparation?
plan, right patient, right or left side, pre-medication, equiptment, drugs drawn up, monitoring, fluid management.
Give 2 examples of iv induced drugs. And the a-d time.
Propofol, Thiopentone. Rapid, 1a-b circulation is roughly 20seconds.
what sense is the last to be lost when anaesthesia is induced?
hearing
what are the difficulties associated with iv induction?
easy to overdose, rapid loss of airway reflexes, apnoea is very common, no obvious planes
give an example of a gas induces anaesthetic
Sevoflurane (halothane), commonly used in young children, slow, more obvious planes of anaesthesia.
what are the planes of anaesthesia?
analgesia/sedation > excitation > anaesthesia > overdose
how is conciousness monitored?
loss of verbal contact, movement, respiratory patter, EEG, observe te planes of anaesthesia.
what are you aiming for with airways?
the reflexes to be supressed - thus the airway needs to be maintained
where does the tounge rest due to loss of muscle tone?
posterior pharyngeal wall
how is the airway maintained
head tilt, chin lift, jaw thrust (triple airway manoevre), then use a face mask, oropharyngeal airway “guedel airway” (or nasopharyngeal airway)
what does a laryngeal mask do? What doesn’t it do?
maintains the airway BUT doesn’t protect the airway from aspiration. (good choice in a cardiac arrest)
the airway obstruction complicaiton…
due to innefective triple airway manoeuvre, airway device malposition, causing laryngospasm (forced reflex adduction of the vocal cords).
the airway aspiration complication…
due to loss of protective aurway reflexes (gag, swallow, cough) foreign material may become present in the lower airway (gastric contents, blood)
whhat protects the airway from contamination?
cuffed tube in the trachea.
what is endotracheal intubation?
placement of a cuffed tube in the trachea, first the laryngeal reflexes must be abolished. Classic method uses a laryngoscope and muscle relaxant. Then get a grade 1 veiw where you can see the true vocal cords.
why is intubation needed?
protect from gastric contents, need for muscle relaxantion (during a laparotomy), need for tight control of gasses (i.e. o2 levels in neurosurgery), if there is restricted access to airway (i.e.maxfax surgery)
what are the risks to an unconcious patient?
airways! Temperature, loss of other protective reflexes (blinking/corneal absarion, joint positions), venous thromboembolism, consent and identificaiton, pressure areas (patient position).
what are thhe minimum monitoring standards for the patient?
spo2, ecg, nibp, etco2. ALSO temp, urine output, invasive venous/arterial monitoring, ecg, ventilator disconnect.
complications of anaesthetics
airway, breathing, circulation, position, techniques, awareness.
emergence/ awakening
muscle relaxation reversed, anaestetic agents off, resumption of spontaneous respiration, return of airway reflexes/control, extubation. This can be very quick of very, very slow.
conduct of local anaesthesia
iv access, mointoring, spinal, epidural, plexus block, nerve block.
how is recovery conducted?
ABC, pain control, mx of nausea and vomiting post-op, set criteria for discharge back to the ward.
