Pre-Anesthetic Assessment Flashcards
Define a Tranquillizer
A medicinal drug, which reduces tension or anxiety
Define a Sedative
Promotes a calm state or induces sleep
Define an Anxiolytic
Reduces anxiety
Define a Hypnotic
A sleep-inducing drug
What is Dissociative Anesthesia?
A form of Anaethesia, characterized by catalepsy, catatonia, analgesia and amnesia. Does not necessarily involve a loss of consciousness
What is Neuroleptanalgesia?
The combination of a potent sedative analgesic agent (an opioid) and a tranquilizer
Define an Analgesic
A drug that acts to relieve pain
Define an Analeptic
A restorative drug that works to stimulate the CNS
Define Anaesthesia
‘lack of sensation/feeling’
Define General Anaesthesia
A state of unconsciousness produced by a process of controlled, reversible, intoxication of the central nervous system, whereby the patient neither perceives nor recalls noxious stimuli
What is the Triad of General Anaesthesia?
= NAP
1) Narcosis (sleep): e.g. propofol, isoflurane
2) Analgesia (pain relief): e.g. morphine, fentanyl, lidocaine
3) Progessive Muscle relaxation: e.g. diazepam, atracurium, guaifenesin
What are the 2 main categories of substances used to produce general anaesthesia?
1) Inhalational: liquid at room temp and then vaporize easily, or gas at room temp
2) Non-inhalational: mostly injectable agents (IV, IM, SC, Intraperitoneal, oral or per rectum)
Give examples of Inhalational substances used to produce general anaesthesia
Volatile: Ether, Isoflurane or Sevoflurane
Gas: Nitrous Oxide
Give examples of Non-inhalational substances used to produce general anaesthesia
Propofol
Ketamine
Alfaxalone
What History is important to know at the pre-anaesthetic assessment?
- Exercise intolerance: cardio and resp function
- Coughing: cardio and resp function
- Dyspnea
- Recent trauma: increased suspicion of an undiagnosied condition
- Syncope: cardiovascular, resp, neurological and endocrine suspicions
- Time of last meal: is the patient fasted?
- Polyuria and Polydipsia: these will indicate a degree of dehydration
- Vomiting or diarrhea: indicate a degree of dehydration + can result in aspiration at induction of anesthesia
- Previous anesthetic history
- Other: pregnancy, behaviour, seizures
- Concurrent medications!
If a patient is on Cimetidine or Omeprazole, what interaction might occur with what anaesthetic agent?
increases the duration of action of diazepam and midazolam and the toxicity of lidocaine
If a patient is on Ketoconazole, what interaction might occur with what anaesthetic agent?
increase sedation from midazolam and amitriptyline
If a patient is on Phenobarbital, what interaction might occur with what anaesthetic agent?
speeds metabolism of lidocaine
If a patient is on Propranolol or other Beta blockers, what interaction might occur?
prevent tachycardia in response to pain, hypercarbia etc
If a patient is on ACE inhibitors, what interaction might occur with what anaesthetic agent?
can cause hypotension especially when used with acepromazine
If a patient is on Digoxin, what interaction might occur with what anaesthetic agent?
may increase arrhythmias especially with atropine or glycopyrrolate
If a patient is on NSAID’s or Aspirin, what interaction might occur?
Increased side effects of GI or renal disease, or increase clotting times
If a patient is on Furosemide, what interaction might occur with what anaesthetic agent?
can cause hypokalaemia and reduce the antiarrhythmic effect of lidocaine
If a patient is on Aminoglycoside antibiotics, what interaction might occur with what anaesthetic agent?
can be nephrotoxic; they also increase duration of action of neuromuscular blocking agents
