Anaesthetics at WWBH Flashcards
Anesthesia Definition
Anesthesia: lack of sensation/perception
Toronto notes 2016
4 steps to Anaesthetics
- pre-operative assessment
- patient optimization
3. plan anesthetic various types of anesthesia pre-medication airway management monitors induction maintenance extubation
- Post-operative care
Toronto notes 2016
6 As of General Anesthesia
Anesthesia Anxiolysis Amnesia Areflexia (muscle relaxation not always required) Autonomic stability Analgesia
Toronto notes 2016
Types of Anesthesia
- general
- regional
- local
- sedation
Toronto notes 2016
Evaluation of Difficult Airway:
LEMON Look – obesity, beard, dental/facial abnormalities, neck, facial/neck trauma Evaluate – 3-2-1 rule Mallampati score Obstruction – stridor, foreign bodies Neck mobility
Toronto notes 2016
To Assess for Ventilation Difficulty:
To Assess for Ventilation Difficulty: BONES Beard Obesity (BMI>26) No teeth Elderly (age>55) Snoring Hx (sleep apnea)
Toronto notes 2016
Classification of oral opening
Mallampati
1. full view of uvula (body and base of uvula), can see tonsillar pillars
2 body and base of uvula, tonsillar pillars and tonsils (partial view)
3 base of uvula and post-pharyngeal wall
4 hard palate and no other structures visible
• routine pre-operative investigations are only necessary if there are comorbidities or certain
B
Chest Radiograph
C
ECG
B-hCG
Electrolytes and Creatinine
Fasting Glucose Level
H
CBC
Sickle Cell Screen
INR, aPTT
American Society of Anesthesiology Classification
• common classification of physical status at the time of surgery
• a gross predictor of overall outcome, NOT used as stratification for anesthetic risk (mortality rates)
• ASA 1: a healthy, fit patient
• ASA 2: a patient with mild systemic disease
ƒ e.g. controlled Type 2 DM, controlled essential HTN, obesity, smoker
• ASA 3: a patient with severe systemic disease that limits activity
ƒ e.g. stable CAD, COPD, DM, obesity
• ASA 4: a patient with incapacitating disease that is a constant threat to life
ƒ e.g. unstable CAD, renal failure, acute respiratory failure
• ASA 5: a moribund patient not expected to survive 24 h without surgery
ƒ e.g. ruptured abdominal aortic aneurysm (AAA), head trauma with increased ICP
• ASA 6: declared brain dead, a patient whose organs are being removed for donation purposes
• for emergency operations, add the letter E after classification (e.g. ASA 3E)
Layers traversed by spinal needle
google: The layers traversed by the spinal needle are the skin, subcutaneous tissue, supraspinous ligament, interspinous ligament, ligamentum flavum and the dura
max dose of ligdocaine
Trilon said 2mg/kg
Lx spinous processes found between iliac crests
L4 spinous processes found between iliac crests
Preoperative medication to stop: oral antihyperglycemic
stop morning of surgery
Preoperative medication to stop: antidepressant
stop on morning of surgery
Preoperative medication to stop:
ACE inhibitors and angiotension receptor blockers
may stop on morning of surgery (controversial)
Preoperative medication to stop:
ASA, NSAIDs
discussed with surgeons
Preoperative medication to stop:
ASA in non-cardiac surgery
in patients undergoing non-cardiac surgery, starting or continuing low-dose aspirin in the perioperative period does not appear to protect against post-operative MI or death, but increases the risk of major bleeding
– note: this does not apply to patients with bare metal stents or drug-eluting coronary stents
3 medications to adjust in pre-operative period
• insulin (consider insulin/dextrose infusion or holding dose), prednisone, bronchodilators
BP targets perioperatively
BP <180/110 is not an independent risk factor for perioperative cardiovascular complications
• target sBP <180 mmHg, dBP <110 mmHg
• assess for end-organ damage and treat accordingly
• ACC/AHA Guidelines (2014) recommend that at least x days should elapse after a MI before a noncardiac surgery in the absence of a coronary intervention
60
- this period carries an increased risk of reinfarction/death
mortality with perioperative MI is x
20-50%
perioperative β-blockers
-may decrease cardiac events and mortality (controversial, as recent data suggests increased stroke risk)
continue β-blocker if patient is routinely taking it prior to surgery
- consider initiation of β-blocker in: patients with CAD or indication for β-blocker OR intermediate risk surgery, especially vascular surgery
smoking effect on physiology that negatively impacts surgery
adverse effects: altered mucus secretion and clearance, decreased small airway caliber, and altered immune response
how long to abstrain from smoking preoperatively
abstain at least 8 wk pre-operatively if possible
if unable, abstaining even 24 h pre-operatively has shown benefit
avoid non-selective β-blockers due to risk of x
bronchospasm
delay elective surgery for poorly controlled asthma
delay elective surgery for poorly controlled asthma (increased cough or sputum production, active wheezing)
delay elective surgery by a minimum of x wk if patient develops URTI
6
pre-operative x for all COPD stage x patients to assess baseline respiratory acidosis and plan post-operative management of hypercapnea
cancel/delay elective surgery for x
ABG
Stage II and III
acute exacerbation
β1-receptors are located primarily in the x
heart and kidneys
β2-receptors are located in the x
lungs
Cardioselective Beta blockers for B1
MANBABE
Metoprolol Atenolol Nebivolol Bisoprolol Acebutolol Betaxolol Esmolol
Fasting guidelines•
x h after a meal that includes meat, fried or fatty foods
8
Fasting guidelines•
x h after a light meal (such as toast or crackers) or after ingestion of infant formula or nonhuman milk
6
Fasting guidelines•
• x h after ingestion of breast milk
4
Fasting guidelines•
x h after clear fluids (water, black coffee, tea, carbonated beverages, juice without pulp)
2
What to do for addison’s disease intraoperatively
consider intraoperative steroids
The only indispensable monitor
the anaesthetist
Inadequate anesthetic depth
blink reflex present when eyelashes lightly touched, HTN, tachycardia, tearing or sweating
excessive anesthetic depth
hypotension, bradycardia
resistance to airflow through nasal passages accounts for approximately x of total airway resistance
2/3
pharyngeal airway extends from
posterior aspect of the nose to cricoid cartilage
what is glottic opening
triangular space formed between the true vocal cords
What is the triangular space formed between the true vocal cords
glottic opening
Which vertebrae does the trachea begin at?
C6
Trachea bifurcates at which vetebral level?
T4-T5 (approximately the sternal angle)
- non-definitive airway (patent airway)
ƒ jaw thrust/chin lift
ƒ oropharyngeal and nasopharyngeal airway
ƒ bag mask ventilation
ƒ laryngeal mask airway
- definitive airway (patent and protected airway)
ƒ endotracheal tube
ƒ surgical airway (cricothyrotomy or tracheostomy)
LMA sizing
3: 40-50
4: 50-70
5: 70-100
• align the three axes (x, x, x,) to allow
mouth, pharynx, and larynx
sniffing position
ƒ “sniffing position”: flexion of lower C-spine (C5-C6), bow head forward, and extension of upper C-spine at atlanto-occipital joint (C1), nose in the air
ƒ contraindicated in known/suspected C-spine fracture/instability
• laryngoscope tip placed in the epiglottic x in order to visualize cord
epiglottic vallecula
Medications that can be Given Through the ETT
NAVEL Naloxone Atropine Ventolin Epinephrine Lidocaine
laryngoscopy and ETT insertion can incite a significant sympathetic response via stimulation of cranial nerves x and x due to a “foreign body reflex” in the trachea, including x
9 and 10
including tachycardia, dysrhythmias, myocardial ischemia, increased BP, and coughing
• a malpositioned ETT is a potential hazard for the intubated patient
- if too deep, may result in x
deep, may result in right endobronchial intubation, which is associated with left-sided
atelectasis and right-sided tension pneumothorax
• a malpositioned ETT is a potential hazard for the intubated patient
- if too shallow, x
- if too shallow, may lead to accidental extubation, vocal cord trauma, or laryngeal paralysis as a result of pressure injury by the ETT cuff
• the tip of ETT should be located at the midpoint of the trachea at least x cm above the carina and the proximal end of the cuff should be placed at least x cm below the vocal cords
- approximately x cm mark at the right corner of the mouth for men and x cm for women
• the tip of ETT should be located at the midpoint of the trachea at least 2 cm above the carina and the proximal end of the cuff should be placed at least 2 cm below the vocal cords
- approximately 20-23 cm mark at the right corner of the mouth for men and 19-21 cm for women
Confirmation of Tracheal Placement of ETT
direct
vs
• indirect
direct
- visualization of ETT passing through cords
- bronchoscopic visualization of ETT in trachea
• indirect
- ETCO2 in exhaled gas measured by capnography
- auscultate for equal breath sounds bilaterally and absent breath sounds over epigastrium
- bilateral chest movement, condensation of water vapour in ETT visible during exhalation and no abdominal distention
- refilling of reservoir bag during exhalation
- CXR (rarely done): only confirms position of the tip of ETT and not that ETT is in the trachea
Esophageal intubation suspected when
• esophageal intubation suspected when
- ETCO2 zero or near zero on capnography
- abnormal sounds during assisted ventilation
- impairment of chest excursion
- hypoxia/cyanosis
- presence of gastric contents in ETT
- distention of stomach/epigastrium with ventilation
Complications During Laryngoscopy and Intubation
Complications During Laryngoscopy and Intubation
• dental damage
• laceration (lips, gums, tongue, pharynx, esophagus)
• laryngeal trauma
• esophageal or endobronchial intubation
• accidental extubation
• insufficient cuff inflation or cuff laceration: results in leaking and aspiration
• laryngospasm (see Extubation, A18 for definition)
• bronchospasm
Differential Diagnosis of Poor Bilateral Breath Sounds after Intubation
Differential Diagnosis of Poor Bilateral Breath Sounds after Intubation DOPE Displaced ETT Obstruction Pneumothorax Esophageal intubation
• if difficult airway expected, consider
- awake intubation
- intubating with bronchoscope, trachlight (lighted stylet), fibre optic laryngoscope, glidescope, etc.
• if intubation unsuccessful after induction
• if intubation unsuccessful after induction
- CALL FOR HELP
- ventilate with 100% O2 via bag and mask
- consider returning to spontaneous ventilation and/or waking patient
• if bag and mask ventilation inadequate
• if bag and mask ventilation inadequate
- CALL FOR HELP
- attempt ventilation with oral airway
- consider/attempt LMA
- emergency invasive airway access (e.g. rigid bronchoscope, cricothyrotomy, or tracheostomy)
small decrease in saturation below SaO2 of x% corresponds to a large drop in arterial partial pressure of oxygen (PaO2)
small decrease in saturation below SaO2 of 90% corresponds to a large drop in arterial partial pressure of oxygen (PaO2)
cyanosis can be detected at SaO2
cyanosis can be detected at SaO2 <85%, frank cyanosis at SaO2 = 67%
nasal prongs, nasopharynx acts as an anatomic x that collects O2
nasopharynx acts as an anatomic reservoir that collects O2
- delivered oxygen concentration (FiO2) can be estimated by adding x% for every additional litre of O2 delivered
- provides FiO2 of 24-44% at O2 flow rates of 1-6 L/min
- delivered oxygen concentration (FiO2) can be estimated by adding 4% for every additional litre of O2 delivered
- provides FiO2 of 24-44% at O2 flow rates of 1-6 L/min
hudson mask
ƒ fed by small bore O2 tubing at a rate of at least x L/min to ensure that exhaled CO2 is flushed through the exhalation ports and not rebreathed
ƒ fed by small bore O2 tubing at a rate of at least 6 L/min to ensure that exhaled CO2 is flushed through the exhalation ports and not rebreathed
provides FiO2 of x% at O2 flow rates of 10 L/min
provides FiO2 of 55% at O2 flow rates of 10 L/min
non-rebreather mask
ƒ a reservoir bag and a series of one-way valves prevent expired gases from re-entering the bag
ƒ during the exhalation phase, the bag accumulates with oxygen
ƒ provides FiO2 of x% at O2 flow rates of 10-15 L/min
80
Venturi mask
ƒ delivers specific FiO2 by varying the size of x
ƒ oxygen concentration determined by x and x
Venturi mask
ƒ delivers specific FiO2 by varying the size of air entrapment
ƒ oxygen concentration determined by mask’s port and NOT the wall flow rate
What is the common name for assist-control ventilation
volume control
in basic pg 41 it says
assist-control = volume control = IPPV = volume control
high-frequency oscillatory ventilation (HFOV)
ƒ high breathing rate (up to x breaths/min in an adult), very low tidal volumes
ƒ used commonly in x
ƒ used in adults when x
high-frequency oscillatory ventilation (HFOV)
ƒ high breathing rate (up to 900 breaths/min in an adult), very low tidal volumes
ƒ used commonly in neonatal and pediatric respiratory failure
ƒ used in adults when conventional mechanical ventilation is failing
Causes of hypocapnea
hyperventilation
hypothermia
Decreased pulmonary blood flow
Technical issues
V/Q mismatch
causes of Hypercapnea
hypoventilation
hyperthermia and other hypermetabolic states
improved pulmonary blood flow after resuscitation or hypotension
technical issues
low bicarb (i don’t understand this)
Positive End Expiratory Pressure (PEEP)
• Positive pressure applied at the end of ventilation that helps to keep alveoli open, x V/Q mismatch
decreasing
x should be considered in patients who require ventilator support for extended periods of time
• Shown to improve patient x and give patients a x
Tracheostomy should be considered in patients who require ventilator support for extended periods of time
• Shown to improve patient comfort and give patients a better ability to participate in rehabilitation activities
Management of pneumothorax in patients on mechanical ventilation?
chest tube
hypoxia vs hypoxemia
google: Hypoxemia is defined as a decrease in the partial pressure of oxygen in the blood whereas hypoxia is defined by reduced level of tissue oxygenation
Causes of hypoxemia
Inadequate oxygen supply
e.g. breathing system disconnection, obstructed or malpositioned ETT, leaks in the anesthetic machine, loss of oxygen supply
Hypoventilation
Ventilation-perfusion inequalities
e.g. atelectasis, pneumonia, pulmonary edema, pneumothorax
Reduction in oxygen carrying capacity
e.g. anemia, carbon monoxide poisoning, methemoglobinemia, hemoglobinopathy
Leftward shift of the hemoglobinoxygen saturation curve
e.g. hypothermia, decreased 2,3-BPG, alkalosis, hypocarbia, carbon monoxide poisoning
Right-to-left cardiac shunt
5 causes of hypoxemia
These are V/Q mismatch, right-to-left shunt, diffusion impairment, hypoventilation, and low inspired PO2.
paper: Mechanisms of hypoxemia
Causes of Hyperthermia (>37.5-38.3ºC)
Causes of Hyperthermia (>37.5-38.3ºC) • drugs (e.g. atropine) • blood transfusion reaction • infection/sepsis • medical disorder (e.g. thyrotoxicosis) • malignant hyperthermia • over-zealous warming efforts
Impact of Hypothermia (<36°C)
Impact of Hypothermia (<36°C)
• Increased risk of wound infections due to impaired immune function
• Increases the period of hospitalization by delaying healing
• Reduces platelet function and impairs activation of coagulation cascade
increasing blood loss and transfusion requirements
• Triples the incidence of VT and morbid cardiac events
• Decreases the metabolism of anesthetic agents prolonging postoperative
recovery
• tachycardia = HR >x bpm;
divided into what 2 groups
• tachycardia = HR >150 bpm; divided into narrow complex supraventricular tachycardias (SVT) or wide complex tachycardias
examples of SVT
• SVT: sinus tachycardia, atrial fibrillation/flutter, accessory pathway mediated tachycardia, paroxysmal atrial tachycardia
examples of wide complex tachycardia
wide complex tachycardia: VT, SVT with aberrant conduction
• causes of sinus tachycardia
ƒ shock/hypovolemia/blood loss
ƒ anxiety/pain/light anesthesia
ƒ full bladder
ƒ anemia
ƒ febrile illness/sepsis
ƒ drugs (e.g. atropine, cocaine, dopamine, epinephrine, ephedrine, isoflurane, isoproterenol, pancuronium)
ƒ Addisonian crisis, hypoglycemia, transfusion reaction, malignant hyperthermia
How much in ligdocaine 1%, 5mL
10mg
Jeremy Broad taught me this trick
How much in Ropivocaine 0.2%, 15mL
30mg
Jeremy Broad taught me this trick
How much in Bupivocaine 3%, 1.5mL
45mg
Jeremy Broad taught me this trick
definition of anaesthesia
pharmacologically induced lack of sensation
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triad of anaesthesia
old concept that anaesthesia consists of three components
- narcosis/sleep
- relaxation
- analgesia
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Which is a deeper plane of anaesthetia, consciousness or movement?
movement
so if a patient is moving, doesn’t necessarily mean they are awake
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inducing paralysis allows a lighter plane of anaesthesia to be used, but eliminates the most reliable and important sign of light anaesthesia and awremness
both voluntary and involuntary movement
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what is the most important protective reflex that is spared by light anaesthetsia?
cardiovascular reflexes
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Measurement of _________ is used to infer the partial pressure in the brain
expired anaesthetic gas partial pressure
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Computerized pumps can deliver IV agents such as x according to complex algorithms that depend on height, weight and body surface area
remifentanil and prpofol
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What does BIS stand for
bispectral index
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Where does BIS monitor electrical activity?
cortical pyramidal cells
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BIS numbers to know
Less than 70=loss of recall
60= unconsciousness
40-60 = surgical anaesthesia
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What is MAC
minimal alveolar concentration
concentration of volatile anaesthetic agent at one atmosphere that will prevent a motor response to a painful stimulus in 50% of subjects
in humans=skin incision
mice=tail clamping
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What is the MAC of isoflurane?
1.1%
or 1.1 kPA
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What is the MAC of sevoflurane
1.8%
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Increasing age and decreasing temperature x the MAC of anaesthetic agents
reduce
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Decreasing age and increasing temperature x the MAC of anaesthetic agents
increase
Increasing barometric pressure x the MAC of anesthetic drugs
increases
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Decreasing barometric pressure x the MAC of anesthetic drugs
decreases
Where is the site of action of volatile anaesthetic agents?
site remains uncertain
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There is a strong correlation between x of a volatile anaesthetic agent and its potency
lipid solubility
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Volatile anaesthetic agents most likely site of action?
hydrophobic regions, most likely cell membranes
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Propofol and barbiturates are the IV anaesthetic agents both thought to work at?
Gamma-aminobutyric acid receptors (GABA) by increasing chloride conductance which hyperpolarises the membrane and inhibits impulse transmission
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What are GABA receptors?
chloride ion channels
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Examples of adjuvants that affect depth of anaesthesia but they cannot by themselves induce anaesthesia
opiods and benzodiazepines
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Opiods act on?
opiod receptors found throughout the CNS
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Benzodiazepines act on?
GABA recetptors
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In an anaesthetic context, what does awareness mean?
being conscious during a surgical procedure
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Are awareness and recall different?
Highy likely based on isolated arm technique study
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Cases at high risk of awareness are?
bronchoscopy
Caesarean section
Trauma cases
Cardiac surgery
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In C-sections, where is light anaesthesia the aim at least until delivery?
most anaesthetic agents cross the placenta and cause sedation of the baby
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In cases of ruptured aortic aneurysm, light anaesthesia is required so not to depress x
cardiovascular reflexes and further lower BP and CO
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What does TAP stand for?
Transverse abdominus plane
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The Brachial plexus is formed by the …
anterior rami of C5-T1
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Term that covers both spinal and epidural blocks
central neural blockade
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Spinal cord ends in adults at about
L1-2
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Name the line between the iliac crests?
Tuffier’s line
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Where is the epidural space
extends from teh foramen magnum to the lower sacrum
LA or a cateter can be inserted into it at any level
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Sympathetic outflow from the spinal cord is from …
T1 - T12
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Sympathetic nerves innervate the smooth muscle of blood vessels and blockade causes …
vasodilation and hypotension
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What is a high spinal or total spinal?
epidural dose of LA is accidentally injected into the subarachnoid space and the phrenic nerve is blocked, then intubation and assisted ventilation are required
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x in the spinal canal is a very serious complication and great care must be taken to prevent
infection
contraindicated in patients with infect, broken skin, or systemic sepsis
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neuroaxial blockade in patients taking anticoagulation is controversial because
formation of epidural haematoma
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signs and symptoms of spinal haematoma
backache
paraplegia
urinary retention
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x is generally considered an absolute contraindication to neuraxial blockade
full anticoaulation
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epidurals should not be performed within x hours of prophylactic administration of low-dose LMWH
12
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epidurals should not be performed within x hours of prophylactic administration of high-dose heparin
24
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an epidural catheter should not be manipulated or removed with in x hours of heparin dose
12
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at least x hrs should pass following removal of a catheter before further heparin is given
2
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Location of a spinal headache?
frontal or occipital
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Treatment for a spinal headache?
bed rest
darkened quiet room
simple analgesics
well hydrated
OR
blood patch is the definitive treatment
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Should mobilization occur after a blood patch?
yes
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Max doses of lignocaine lignocaine with adrenaline ropivucaine bupivucaine
3mg/kg
7mg/kg
3mg/kg
2mg/kg and easy to remember because B is 2nd letter in alphabet
-dilraj thind
Define Sedation
CNS depression without LOC
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Can sedation be used to compensate for inadequate local anaesthesia?
no
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4 major IV sedation agents
benzos
opiods
major tranquillisers
propofol
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Propofol is a small step from sedation to anaesthetic, where you lose xx
loss of airway and other reflexes
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Antidote for opiod overdose
naloxone
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antidote for benzo overdose
flumazenil
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Australia college of anaesthetics minimum monotiring for sedation is
BP
oximietry
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Patients that have sedation should NOT x for 24 hours
drive
operate machinery
make important decisions
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Define pharmacokinetics
What the body does to the drug
ADME= absorption distribution metabolism elimination
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Define pharmacodynamics
What the drug does to the body
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Explain the two compartment model
central compartment=circulating blood volume + well perfused tissues (brain, liver, kidenys lungs)
peripheral compartment=received much smaller proportion of cardiac output
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Volume of distribution
Wiki
It is the ratio of amount of drug in a body (dose) to concentration of the drug that is measured in blood, plasma, and un-bound in interstitial fluid.[3][4]
The VD of a drug represents the degree to which a drug is distributed in body tissue rather than the plasma. VD is directly proportional with the amount of drug distributed into tissue; a higher VD indicates a greater amount of tissue distribution. A VD greater than the total volume of body water (approximately 42 liters in humans[5]) is possible, and would indicate that the drug is highly distributed into tissue. In other words, the volume of distribution is smaller in the drug staying in the plasma than that of a drug that is widely distributed in tissues.[6]
In rough terms, drugs with a high lipid solubility (non-polar drugs), low rates of ionization, or low plasma protein binding capabilities have higher volumes of distribution than drugs which are more polar, more highly ionized or exhibit high plasma protein binding in the body’s environment
Two main routes of clearancd
renal and hepatic
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what is a Phase I reaction
in hepatocytes, oxidation, reduction and hydrolysis
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What is a phase II reaction
in hepatocytes, conjugation to make a substance more soluble and thus excretable
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The elmination half-life of a drug is x to its VD
proportional
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The elmination half-life of a drug is x to its clearance
inversely proportional
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In pharmacology, K refers to
rate constant
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drugs that are more lipid soluble tend to be x protein bound
more highly
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protein binding will x the VD
increase, as it removes drugs from the plasma event though the protein bound drug is freely interchangeable with the non-bound drug
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When plasma proteins beome saturated with the drug, a small increase in the dosage can lead to a x
large increase in plasma concentration
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The x form of a drug is the form that passes readily through cell membranes
non-ionised
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Define Potency
dose of a drug that is required to gain the required effect
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dose of a drug that is required to gain the required effect
potency
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ED50
Effective dose 50
dose required to have that effect in 50% of patients
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Define Efficacy
efficacy refers to the maximal effect that a drug can have
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What common receptor do endorphins and encephalins act on?
opiod receptor
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What is the mech of action of inhaled anaesthetic agents?
has not been deteremined
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There is a strong corelation between x and potentecy of inahled anaesthetic agents
lipid solubility
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Unlike IV drugs, where effect is determined by receptor occupancy, the effect of inhalational agents is proportional to the X of the agent in the CNS
partial pressure
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The more blood soluable, the x it will take to equilibrate
longer
the way i think about it is it needs to disovle into the blood, and then it can be in gas form into the blood
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An anaesthetic vapour with a lower blood/gas solubility and lower brain/blood solubility will eqilibrate with the brain xx than will more soluble drugs and it will have a x onset and offset
more quickly
quicker
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Propofol has replaced x as the most commonly used induction agent
thiopentone
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Propofol comes as a x% solution
1%
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Rapid clearance of propofol is due to x and x
metabolism in liver + redistribution
-Anaesthesia an introduction harley and hore pg38
Propofol is associated with a x incidence of nausea and vomitting
low
-Anaesthesia an introduction harley and hore pg38
Thiopentoneo can cause x if injected intra-arterially
ischemia
-Anaesthesia an introduction harley and hore pg38
Which cases a greater drop in blood pressure?
propofol vs thiopentone
propofol
-Anaesthesia an introduction harley and hore pg38
What class is thiopentone?
barbituate
-Anaesthesia an introduction harley and hore pg38
Thiopentone has x onset
options: rapid vs slow
rapid
-Anaesthesia an introduction harley and hore pg38
Why does thiopentone rapidly equilibrate with the brain?
high blood flow
-Anaesthesia an introduction harley and hore pg38
Thiopentone is metabalized by the x
liver
-Anaesthesia an introduction harley and hore pg38
Thiopentone is excreted by the
liver and kidneys
-Anaesthesia an introduction harley and hore pg38
Thipenton has a x elimination half life
slow
-Anaesthesia an introduction harley and hore pg38
How to anaesthetic agents decrease BP?
decrease sympathetic outflow
-Anaesthesia an introduction harley and hore pg38
What was the first modern anaesthetic developed?
Halothane
-Anaesthesia an introduction harley and hore pg38
Halothane has a x solubility than other commonly used vapours
higher
-Anaesthesia an introduction harley and hore pg38
All potent anaesthetic vapours have been associated with post-exposure
hepatitis
-Anaesthesia an introduction harley and hore pg38
MAC of halothane is
- 7%
- Anaesthesia an introduction harley and hore pg38
