Special Care (PTSR) Flashcards
What are the systemic effects of Nitrous Oxide on:
- CNS?
- Respiratory system?
- Haemotopoeitic system?
- GI, Liver & Kidney?
- Vasodilation
- Respiratory depression (Reduced rate and depth)
- Bone marrow suppression
- NOTHING :)
What is meant by the “Triad of Anaesthesia”?
What anaesthetic agent does not achieve one of these?
- Hypnosis/Sedation
- Muscle relaxation
- Analgesia
MIDAZOLAM (pre-GA anxiolytic or conscious sedative) does NOT provide Analgesia
What drug is used to reverse effects of Midazolam? How?
When might its use be contra-indicated? (2)
Flumazenil (Competetive antagonist at Benzodiazepine receptor)
Reverses ALL effects of Midazolam (Muscle relaxation, Respiratory depression, Cardiovascular effects) EXCEPT Anterograde Amnesia
Contra-indications:
- Epileptic Px on CNS active drugs (may reverse effects of anti-convulsant meds → epileptic fit)
- Midazolam allergies (Flumazenil is a benzodiazepine too!)
Define the following:
- Pharmacokinetics
- Drug Distribution
- Drug Clearance/Elimination
- Pharmacodynamics
PHARMACOKINETICS = The movement of a drug through the body, split into a 2-part curve:
- Drug Distribution
- Drug Elimination
DRUG DISTRIBUTION = The movement of a drug in which peak blood level represents the amount of drug injected. This falls as the drug is distributed into the tissues
DRUG ELIMINATION = Volume of plasma which is cleared of the drug within a unit time
PHARMACODYNAMICS = What the drug does to an individual
DYNAMICS =
What are the 2 stages of recovery after GA?
- Fully awake, protective reflexes return, Observations stabilise and Pain is controlled (analgesia)
- Ready for discharge with “reasonable adjustments” with responsible adult escort
What are 4 signs of oversedation?
How is:
- Small
- Gross
oversedation managed?
- Nausea/Vomiting
- Uncooperative (e.g. constant mouth closing)
- Irregular respiratory rate
- Loss of cosciousness!
SMALL OD (e.g. uncooperative) ⇒ Wait few mins (usually resolves) and give O2
GROSS OD (e.g. profound respiratory depression) ⇒ STOP, Secure airway, ventilate if not breathing and reverse with FLUMAZENIL
Why is pre-medication given before GA? (3)
What are the 2 main types? (give examples)
- Reduce anxiety
- Reduce pre and post-op pain
- Produce amnesia
- (Oral) Sedatives (e.g. Midazolam or Ketamine) → Anxiolysis
- Topical LA creams (used pre-cannula)
RLH accept GA referals for patients in ASA 1-3, define the American Society of Anaesthesia (ASA) classifications 1-6…
What is the MOA of Midazolam?
How is it’s function incfluenced by: Age and CNS active drug use?
GABA receptor agonist (present throughout the body) → Cl- entry → Cell inhibition
Age = Decrease in receptors around the body, slower circulation and paradoxical effects
CNS Active Drug Users = Altered receptor activity (they become “Hypo-active” responders who require more drug to sedate)
What is the 2 stage test for Capacity?
What are 5 options if the Px lacks capacity?
- Is there an impairment or disturbance in the functioning of Px mind or brain?
- If so, is the impairment sufficient that the person lacks capacity to make a decision?
- Act in Px best interest
- Advanced directives (Px in cognitive decline makes decisions in advance)
- Lasting Power of Attorney (nominated by Px)
- Court-Appointed deputy
- Independent Mental Capcity Advocate (IMCA)
What are 6 signs/symptoms of anxiety?
- Behavioural changes: Excessive talking (delay tactic), Lateness, DNA or Aggression
- Pallor or flushing of face
- Sweatiness (esp. facial)
- Increased HR
- Dry mouth
- Fainting
What are the 4 “Pharmacodynamics” (effects) of Midazolam?
- Muscle relaxant
- Respiratory depression (mild) - Pulse oximeter monitoring
- Anterograde Amnesia
- Cardiovascular effects via PsNS - Decreased MAP, CO, SV and Systemic vascular resistance
Why are patients “starved” pre-GA?
What fasting instructions should be given to patients?
To reduce the likelihood of stomach contents being regurgitated and then aspirated into the lungs
- Stop eating solid foods 6 HOURS before GA (e.g. 2am for 8am GA)
- Stop drinking fluids for 2 HOURS before GA (e.g. 6am for 8am GA)
Medications can be taken between this period, except if contraindicated (e.g. Type 2 diabetics should NOT take morning meds)
Outline the differences in:
- Px response during procedure
- Px airways (un/affected & whether intervention required)
- Spontaneous ventilation
- Cardiovascular function
between Pre-medication (Anxiolytic Sedatives), Conscious Sedation and General Sedation…
What are 5 contra-indications to GA?
(3 are MH conditions)
- Allergies to GA drugs (e.g. Propafol, Fentanyl, Sevoflurane)
- Advanced cardio-respiratory disease
- Suxamethonium apnoea
- Malignant Hyperthermia
- No escort