Anaesthetics: General Anaesthetic Agents & Induction/Maintenance Flashcards
1
Q
What are the 3 main categories of anaesthesia?
A
1) General: making the patient unconscious
2) Regional: blocking feeling to an isolated area of the body (e.g., a limb)
3) Local
2
Q
Purpose of fasting before a planned general anaesthetic?
A
Ensure empty stomach –> reduce risk of stomach contents refluxing into oropharynx (throat) –> reduce risk of aspiration into the trachea.
Gastric contents in the lungs creates an aggressive inflammatory response, causing pneumonitis (inflammation of the lung tissue).
3
Q
When is the risk of aspiration highest during general anaesthesia?
A
Before and during intubation, and when they are extubated.
4
Q
What does fasting for an operation typically include?
A
1) 6 hours of no food or feeds before the operation
2) 2 hours of no clear fluids (‘nil by mouth’)
5
Q
What is ‘preoxygenation’ in surgery?
A
Before being put under a general anaesthetic, the patient will have a period of several minutes when they breathe 100% oxygen.
6
Q
Purpose of preoxygenation prior to general anaesthetic?
A
This gives them a RESERVE of oxygen for the period between when they lose consciousness and are successfully intubated and ventilated (in case the anaesthetist has difficulty establishing the airway).
N.B. This step may need to be skipped when an emergency general anaesthetic is required.
7
Q
Medications are given before the patient is put under a general anaesthetic.
What may these include?
A
1) Benzodiazepines (e.g. midazolam)
2) Opiates (e.g. fentanyl or alfentanyl)
3) Alpha-2-adrenergic agonists (e.g., clonidine)
8
Q
Purpose of benzos prior to general anaesthetic?
A
To relax the muscles and reduce anxiety (also causes amnesia)
9
Q
Purpose of opiates prior to general anaesthetic?
A
to reduce pain and reduce the hypertensive response to the laryngoscope
10
Q
Purpose of alpha-2-adrenergic agonists prior to general anaesthetic?
A
Can help with sedation and pain
11
Q
Give an example of an alpha-2-adrenergic agonist used prior to general anaesthetic
A
Clonidine
12
Q
What is rapid sequence induction/intubation (RSI)?
A
Used to gain control over the airway as quicky and safely as possible where a patient is intubated in an EMERGENCY scenario and detailed pre-planning is not possible.
The procedure is designed to ensure successful intubation with an endotracheal tube as soon as possible after induction (when the patient is unconscious) to protect the airway.
13
Q
Why is RSI more risky?
A
Ass the patient has often not been fasted (risk of aspiration), and the anaesthetist has not had the chance to plan for individual factors and potential problems (e.g., a difficult airway).
14
Q
When is RSI used?
A
a) emergency scenario
b) non-emergency scenario where the airway needs to be secured quickly to avoid aspiration e.g. in patients with gastro-oesophageal reflux or pregnancy.
15
Q
What is the biggest concern during RSI?
A
Aspiration of stomach contents into the lungs.
16
Q
How can the risk of aspiration be reduced in RSI?
A
1) Position bed so the patient is more upright to reduce reflux of contents up the oesophagus
2) Cricoid pressure (pressing down on the cricoid cartilage in the neck): can compress the oesophagus and prevent the stomach contents from refluxing into the pharynx
17
Q
What should you be aware of regarding cricoid pressure in RSI?
A
This is somewhat controversial and should only be done by someone trained and experienced.
18
Q
What is the triad of general anaesthesia?
A
1) Hyponosis
2) Muscle relaxation
3) Analgesia
19
Q
Purpose of hypnotic agents in anaesthesia?
A
Used to make the patient unconscious.
20
Q
How are hypnotic agents given?
A
IV or inhaled
21
Q
What is the most commonly used IV hyponotic agent?
A
Propofol
22
Q
What is the most commonly used inhaled hypnotic agent?
A
Sevoflurane
23
Q
Give 4 options for IV hypnotic agents
A
1) Propofol
2) Ketamine
3) Thiopental sodium (less common)
4) Etomidate (rarely used)
24
Q
Give 4 options for inhaled hypnotic agents
A
1) Sevoflurane
2) Desflurane (less favourable as bad for the environment)
3) Isoflurane (rarely used)
4) Nitrous oxide (combined with other anaesthetic medications – may be used for gas induction in children)
25
Sevoflurane, desflurane and isoflurane are volatile anaesthetic agents.
What does this mean?
Volatile agents are liquid at room temperature and need to be vaporised into a gas to be inhaled.
26
What device is used for iinhaled volatile agents?
Vaporiser devices
27
How do vaporiser devices work?
1) Liquid medication is poured into machine
2) Machine turns it into vapour and mixes it with air in a controlled way
3) During the anaesthesia, the concentration of the vaporised anaesthetic medication can be altered to control the depth of anaesthesia.
28
How will IV vs inhaled hyponotic agents commonly be used during operations?
Why?
IV medication will be used as an induction agent (to induce unconsciousness) --> are infused directly into the blood and so can quickly reach an effective concentration.
Inhaled medications will be used to maintain the general anaesthetic during the operation --> need to diffuse across the lung tissue and into the blood, where it takes a while for them to reach an effective concentration.
29
What does total IV anaesthesia (TIVA) involve?
Involves using an IV medication for induction and maintenance of the general anaesthetic.
30
What is the most commonly used agent for TIVA?
Propofol
31
Benefit of TIVA over inhaled options?
Can give a nicer recovery as they wake up compared with inhaled options.
32
How is propofol given?
IV
33
What is propofol?
A general anaesthetic
34
Indication for propofol?
1) induction agent
2) intensive care for ventilated patients
35
Mechanism of propofol?
1) Decreases the rate of dissociation of GABA from its receptor
2) Which increases the duration of the GABA-activated opening of the chloride channel
3) Leads to hyperpolarisation of cell membranes
4) Increased inhibitory tone in the central nervous system.
36
2 key adverse effects of propofol?
1) Pain on injection
2) Hypotension (marked drop in BP)
37
Why can propofol cause pain on injection?
Due to activation of the pain receptor TRPA1
38
Who is propofol useful in?
Patients with high risk of post-op vomiting --> due to anti-emetic effects.
39
What is thiopental?
a general anaesthetic
40
How is thiopental given?
IV
41
Mechanism of thiopental?
A type of barbiturate.
1) Decreases neuronal activity
2) This decreases cerebral metabolic rate of oxygen consumption
3) This decreases cerebrovascular response to carbon dioxide
4) This decreases intracranial pressure
42
Main side effect of thiopental?
Laryngospasm
43
Benefit of thiopental?
It is very lipid-soluble so affects the brain quickly i.e. mainly used for rapid sequence induction.
44
How do anaesthetic drugs typically work?
1) Bind to GABA receptor to potentiate the action of GABA (a major inhibitory neurotransmitter) --> this leads to the anaesthetic state of unconsciousness, muscle relaxation and analgesia.
2) Also work by opening K+ channels that modulate neuro-excitability --> this reduces membrane excitability.
3) Also inhibit opening of ligand-gated ion channels that allow Na+ to enter the cell.
45
Why does opening K+ channels cause anaesthetic effect?
Reduces membrane excitability --> will lead to more negative resting potential, making it more difficult to start an action potential.
46
What is etomidate?
General anaesthetic
47
How is etomidate given?
IV
48
Mechanism of etomidate?
Potentiates GABA
49
2 main side effects of etomidate?
1) Primary adrenal suppression (2ary to reversibly inhibiting 11β-hydroxylase)
2) Myoclonus
50
When is etomidate typically used? Why?
Typically used in cases of haemodynamic instability --> causes LESS hypotension than propofol and thiopental during induction.
I.e. mainly used in Cardiac patients Induction (Hemodynamic stability).
51
Mechanism of ketamine?
Blocks NMDA receptors (a receptor of glutamate: the primary excitatory neurotransmitter).
52
2 main adverse effects of ketamine in general anaesthesia?
1) disorientation
2) hallucination
53
Which general anaesthetic acts as a 'dissociative anaesthetic'?
Ketamine
54
When is ketamine favoured as an anaesthetic? Why?
1) In patients with unknown medical history
2) In the treatment of burn victims
3) Trauma
As doesn't cause a drop in blood pressure or depress breathing and circulation as much as other anesthetics.
55
Which general anaesthetic has a side effect of laryngospasm?
Thiopental
56
Which general anaesthetic has a side effect of pain on injection?
Propofol
57
Which general anaesthetic has a side effect of 1ary adrenal suppression?
Etomidate
58
Give 3 examples of volatile liquid anaesthetics
1) sevoflurane
2) isoflurane
3) desflurane
59
What are the 3 stages of a general anaesthetic?
1) induction
2) maintenance
3) emergency
60
Before a general anaesthetic, a comprehensive pre-operative assessment should be performed to determine anaesthetic drug choice and technique.
What should this include?
1) assessment of comorbidities
2) fasting status
3) airway assessment
61
What 4 essential steps should occur before the patient is brought to the operating theatre?
1) Pre-op visit and airway assessment by anaesthetist
2) Theatre team brief
3) Preparation of airway tray, emergency and induction drugs
4) Ventilator check
62
Upon entering the anaesthetic room/theatre, the patient will undergo safety checks and have essential monitoring attached.
This can vary according to the procedure, but at a minimum what does it include?
1) ECG
2) Blood pressure (NIBP)
3) Capnography
4) Anaesthetic depth monitoring
5) SpO2
63
What is the most commonly used device for maintaining an open airway during administration of anesthesia?
Supraglottic device i.e. laryngeal mask airway (LMA)
64
What are the 2 types of airway management of general anaesthesia?
1) Endotracheal tube (ET tube or ETT)
2) Supraglottic Airway (SGA) (E.g. Laryngeal Mask Airway)
65
Where is the SGA placed?
It is a plastic tube with a large cuff that is placed into the back of the throat and is positioned above the opening to the trachea (windpipe).
66
2 benefits of SGA over endotracheal tube?
1) Lower incidence of sore throat
2) Allows patient to easily breathe on their own
67
Contraindications to SGA?
1) Patients with higher risk of reflux e.g. those who have eaten within the previous 6-8 hours, pregnant women, and diabetic patients whose stomachs do not empty properly
2) Laparoscopic surgery
3) Surgery requiring careful control of breathing – includes brain, cardiac and thoracic/chest procedures
4) Prone positioning (surgery performed with the patient lying on their stomach)
5) Surgery in the nose or mouth
6) Obesity
68
Why is SGA contraindicated in patients with higher risk of reflux?
The SGA sits above the opening to the trachea sogases may also be delivered to the stomach via the oesophagus, particularly if the patient is being ventilated (the anesthesiologist is providing breaths for the patient) via the SGA.
This means that anything that is regurgitated could potential go into the lungs --> risk of aspiration.
69
Why is SGA contraindicated in prone positioning (surgery performed with the patient lying on their stomach)?
makes it very difficult or impossible to adjust or replace the SGA if it gets dislodged.
70
Why is SGA contraindicated in laparoscopic surgery?
the high pressure created in the abdomen makes it difficult to ventilate with the SGA
71
Why is SGA not often used in obesity?
1) Increased soft tissue in the airway and neck can make properly placing the SGA more difficult.
2) The added weight of the abdomen can also make ventilation difficult (similar to the pressure created with laparoscopic surgery).
72
What is the most common problem with SGA placement?
What happens if this occurs?
That the device does not fit or seal well enough to deliver adequate amounts of anesthetic gases and oxygen.
In this situation, the SGA is removed and an endotracheal tube is placed.
73
What is an endotracheal tube (ETT)?
A plastic tube that is inserted into the trachea and allows for a direct route of delivery of oxygen and removal of carbon dioxide from the lungs.
74
What is placement of an ETT referred to as?
Intubation
75
During intubation, what is used to displace the tongue and allow visualisation of the vocal cords and airway?
A laryngoscope (blade with a light at the end of it)
76
What is the most common complaint following intubation with ETT?
Sore throat
77
What are some complications of ETT placement?
1) Sore throat
2) Cuts to the lips, tongue, gums, throat
3) Damage to the teeth
4) Hoarseness from temporary or permanent damage to the vocal cords
5) Increased blood pressure or heart rate
6) Asthma exacerbation
7) Brain damage and/or death secondary to inability to intubate
78
As a general rule, what type of airway management is used in patients with any risk of airway soiling (regurgitation, unfasted status) or anticipated difficulty with ventilation?
An endotracheal tube (ETT)
79
Give some examples that may cause anticipated difficulty with ventilation?
1) obesity
2) lung pathology
3) laparoscopic surgery
80
If a patient is considered at high risk of airway soiling, what can be used?
a rapid sequence induction (RSI) technique can be performed
81
What is involved in RSI?
A rapid, successive administration of induction and neuromuscular blocking (paralytic/muscle relaxant agents) drugs to achieve a state of unconsciousness and paralysis in the shortest time possible (usually within less than a minute) to secure the airway.
82
Mechanism of sevoflurane (and the volatile liquid anaesthetics)?
Exact mechanism of action unknown. May act via a combination of GABAA, glycine and NDMA receptors
83
What are the 3 adverse effects of volatile liquid anaesthetics
(isoflurane, desflurane, sevoflurane)?
1) Myocardial depression
2) Malignant hyperthermia
3) Halothane is hepatotoxic (now not commonly used)
84
Why is halothane now not commonly used?
Hepatotoxic
85
How are volatile liquid anaesthetics
(isoflurane, desflurane, sevoflurane) administered?
Inhaled
86
Indications for volatile liquid anaesthetics
(isoflurane, desflurane, sevoflurane)?
Induction and maintenance of general anaesthetics.
87
What is malignant hyperthermia?
A potentially fatal reaction to certain general anaesthetic medications, or the muscle relaxant, suxamethonium.
88
What 2 things is malignant hyperthermia triggered by?
1) exposure to certain volatile inhalation anaesthetics
2) suxamethonium (the depolarising muscle relaxant)
89
What is the most common cause of malignant hyperthermia?
An autosomal dominant mutation in the ryanodine receptor 1.
This results in an abnormality in calcium regulation within muscle cells --> leads to increased calcium levels in the sarcoplasmic reticulum and a consequent increase in metabolic rate.
90
Signs and symptoms of malignant hyperthermia?
1) rapid increase in body temp
2) muscle rigidity
3) metabolic acidosis
4) tachycardia
5) increased exhaled carbon dioxide
91
Give 3 differentials for malignant hyperthermia
1) neuroleptic malignant syndrome: altered mental status, muscle rigidity, fever, and autonomic dysregulation.
2) serotonin syndrome: mental status changes, autonomic instability, and neuromuscular abnormalities.
3) sepsis: fever, tachycardia, and potential organ dysfunction.
92
Definitive diagnosis of malignant hyperthermia?
Genetic testing, typically performed post-episode.
93
Investigations in malignant hyperthermia?
1) genetic testing (definitive)
2) blood tests: metabolic acidosis, creatine kinase levels
3) ABG: resp & metabolic acidosis
4) core temp: hyperthermia
94
How are CK levels affected in malignant hyperthermia?
Increased
95
Management of malignant hyperthermia?
1) Immediate discontinuation of the triggering agent.
2) IV dantrolone
3) Restoration of normothermia
4) Correction of acidosis and electrolyte abnormalities.
5) Supportive e.g. oxygen, ventilation etc
96
What drug is indicated in malignant hyperthermia?
IV dantrolene
97
Mechanism of IV dantrolene in malignant hyperthermia?
It is a ryanodine receptor antagonist --> helps to decrease intracellular calcium concentration and reduce muscle metabolism.
98
How can the restoration of normothermia be achieved in malignant hyperthermia?
Cooling techniques such as ice packs, cool intravenous fluids, and cooling blankets.
99
In what situations should nitrous oxide be avoided in?
E.g. pneumothorax --> may diffuse into gas-filled body compartments and cause an increase in pressure
100
Which general anaesthetic has proven anti emetic properties?
Propofol
101
Which general anaesthetic may cause marked myocardial depression?
Sodium thiopentone
102
Which general anaesthetic is a suitable agent for anaesthesia in those who are haemodynamically unstable?
Ketamine
103
Which general anaesthetic may result in nightmares?
Ketamine
104
Which general anaesthetic is post-op vomiting common in?
Etomidate
105
Purpose of muscle relaxants in general anaesthetics?
They facilitate intubation and improve surgical access (particularly abdominal and laparoscopic procedures).
106
Give 2 muscle relaxant agents
1) suxamethonium
2) rocuronium
107
What does a simple general anaesthetic induction ‘recipe’ for tracheal intubation in a fit and well patient usually incorporate?
A quick acting opioid (e.g. fentanyl) and propofol.
108
How is loss of consciousness confirmed in general anaesthesia?
Loss of vocal response/jaw thrust/eyelash reflex.
109
Intravenous anesthetics work within one arm to brain cycle.
What does this mean?
If the drug is administered through an IV line in the arm, it is the time required to circulate back to the heart and then up to the brain (usually less than 1 minute).
110
What is 'one arm brain cycle'?
The time the drug takes to travel from the point of administration (e.g. cannula in hand) to the effect site (brain).
111
How is tube placement within the trachea confirmed (i.e. what are the 3 essential checks)?
1) Symmetrical chest wall movement
2) Misting within the tube
3) More than 5 waveforms on capnography
These are confirmed whilst delivering 5 test breaths.
112
How many test breaths are delivered whilst confirming tube placement within the trachea?
5
113
Once tube placement is confirmed, what are the next 3 steps?
1) The tube length at the lip or teeth is noted
2) It is secured with a cloth tie or tape to prevent tube migration which may lead to endobronchial intubation or accidental extubation.
3) Patient is connected to ventilator
114
What is the 'maintenance' goal during general anaesthetics?
To maintain a pain-free, unconscious state throughout surgery while ensuring physiological stability.
The choice of maintenance technique depends on the type and duration of surgery and clinician preference.
115
How is a state of unconsciousness maintained during general anaesthetics?
1) Via IV access of inhalation (e.g. sevoflurane).
2) More recently, there has been a move towards total intravenous anaesthesia (TIVA) involving continuous, rapidly titratable IV infusions.
116
What is TIVA usually a combination of?
Anaesthetic agent (e.g. propofol) plus a rapid-acting opioid such as remifentanil.
117
What are 2 advantages of TIVA?
1) improved recovery profiles
2) reduced greenhouse gas emissions
118
It is important to note that a patient can be unconscious but still experience pain during surgery.
What physiological parameters may indicate that an unconscious patient is experiencing pain?
tachycardia & HTN
119
Anaesthetists aim to provide a ‘multimodal analgesia’ strategy for managing pain.
What does this mean?
Administering medications from multiple pharmacological classes to provide effective analgesia and reduce opioid requirements.
120
What is a commonly used analgesiccombination for minor procedures in a healthy patient with no contraindications?
Paracetamol + NSAID + local anaesthetic (to surgical site) + breakthrough opioids if required.
121
Give 2 other techniques for maintaining a pain-free intraoperative state?
1) Bolus or continuous infusion of opioids
2) Regional techniques (e.g. via peripheral nerve blockade or a central neuraxial block – spinal or epidural).
122
What intraoperative monitoring is required?
1) Continuous monitoring of vital signs: blood pressure, heart rate, oxygen saturation, and end-tidal CO2 (capnography).
2) Depth of anaesthesia monitoring
3) Neuromuscular blockade assessment.
123
How is the depth of anaesthesia typically measured?
Give 2 options
1) Using a bispectral index (BIS) monitor
2) Mean alveolar concentration (MAC)
124
What does a BIS monitor analyse?
The brains electrical activity (EEG).
125
When can MAC be used to measure the depth of anaesthesia?
If volatile agents are used to maintain anaesthesia.
126
How can the degree of the neuromuscular blockade be assessed?
Using a peripheral nerve stimulator.
127
Where are the leads typically over in a peripheral nerve stimulator?
Facial ofr ulnar nerve
128
What is the most common physiological change you can expect with a standard general anaesthetic?
Hypotension.
This must be identified and treated promptly to ensure adequate organ perfusion.
129
Cause of hypotension with standard general anaesthetics?
Due to the potent vasodilator effects of most inducation agents (except ketamine and etomidate).
130
Which 2 general anaesthetics do NOT have potent vasodilator effects?
1) ketamine
2) etomidate
131
What drugs can be to increase HR during surgery?
Antimuscarinics e.g. atropine, glycopyrronium.
If this fails --> adrenaline
132
How do muscle relaxants work?
Block the neuromuscular junction from working:
Acetylcholine (the neurotransmitter) is released by the axon but is blocked from stimulating a response from the muscle.
133
What are the 2 categories of muscle relaxants?
1) depolarising (e.g. suxamethonium)
2) non-depolarising (e.g. rocuronium and atracurium)
134
What class of medication can reverse the effects of neuromuscular blocking medications?
Cholinesterase inhibitors (e.g., neostigmine)
135
Give an example of a cholinesterase inhibitor
Neostigmine
136
What medication is used specifically to reverse the effects of certain non-depolarising muscle relaxants (rocuronium and vecuronium)?
Sugammadex
137
What are the 4 commonly used analgesic agents in anaesthetics?
1) fentanyl
2) alfentanil
3) remifentanil
4) morphine
138
When are antiemetics often given in anaesthetics?
Antiemetics are often given at the end of the procedure by the anaesthetist to prevent post-operative nausea and vomiting.
139
What are 3 common antiemetics given for prophylaxis given at the end of the operation?
1) Ondansetron
2) Dexamethasone
3) Cyclizine
140
Mechanism of ondansetron?
5HT3 receptor antagonist
141
Who is ondansetron avoided in?
Patients at risk of prolonged QT interval.
142
Who should dexamethasone as a post-op antiemetic be used with caution in?
Diabetic or immunocompromised patients.
143
Mechanism of cyclizine?
Histamine (H1) receptor antagonist
144
Who cyclizine be used with caution in?
Heart failure & elderly patients
145
What needs to have worn off before waking the patient during general anaesthetics?
Muscle relaxant
146
What can be used to determine whether the muscle relaxants have worn off?
A nerve stimulator: used to test the muscle responses to stimulation to ensure the muscle relaxant effects have ended.
147
Which nerves are commonly tested to see if muscle relaxants have worn off?
1) Ulnar nerve at the wrist: watch for thumb movement (twitches).
2) Facial nerve at the temple: watch for movement in the orbiculares oculi muscle at the eye.
148
What is involved in testing the facial nerve with nerve stimulators?
This involves a train-of-four (TOF) stimulation.
This is where the nerve is stimulated 4 times to see if the muscle responses remain strong (indicating it has worn off) or whether they get weaker with additional stimulation (indicating it has not fully worn off).
149
What result of train-of-four (TOF) stimulation indicates that muscle relaxants haven't fully worn off?
Muscle responses get weaker with additional stimulation.
150
151
Steps in 'emergence' during general anaesthetics?
1) Ensure muscle relaxant has worn off
2) Stop inhaled anaesthetic
3) Extubate when they are breathing for themselves
152
What are the 2 common side effets of general anaesthetics?
1) sore throat
2) post-op N&V
153
What are some significant side effects of general anaesthesia?
1) Accidental awareness (waking during the anaesthetic)
2) Aspiration
3) Dental injury, mainly when the laryngoscope is used for intubation
4) Anaphylaxis
5) Cardiovascular events (e.g., myocardial infarction, stroke and arrhythmias)
6) Malignant hyperthermia (rare)
7) Death
154
What is the main contraindication for thiopentone?
Porphyria
155
How does ketamine affect BP & HR?
Increased HR & BP
156
How long do induction agents typically last?
4-10 minutes
157
What is the most commonly used IV maintenance anaesthesia?
Propofol infusion
158
What are 3 commonly used inhalational agents?
1) Sevoflurane (MAC 2%)
2) Desflurane (MAC 6%)
3) Isoflurane (MAC 1.15%)
159
What is MAC?
It is defined as the minimum alveolar concentration of inhaled anaesthetic at which 50% of people do not move in response to a noxious stimulus.
160
Which inhalational agent is sweet smelling?
Sevoflurane
161
Which inhalational agent has the max greenhouse effect?
Desflurane
162
Which inhalational agent has the least effect on organ blood flow?
Isoflurane --> used in organ donation
163
Adverse effects of suxamethonium?
- muscle pains
- fasciculations
- Hyperkalaemia
- malignant hyperthermia
- rise in ICP, IOP and gastric pressure
164
Give an example of a depolarising muscle relaxant
Suxamethonium
165
Give examples of non-depolarising muscle relaxants
Short-acting: Mivacurium
Intermediate acting: Vecuronium, rocuronium, Atracurium.
Long acting: Pancuronium
166
Benefits of non-depolarising muscle relaxants?
Slow onset and variable duration, less side effects.
167
What is used to reverse non-depolarising muscle relaxants?
Neostigmine & Glycopyrrolate
168
What is the most common short acting opioid used at time of anaesthesia induction?
Fentanyl
169
What is the most commonly used oral opioid in adults?
Codeine
170
Which 2 NSAIDs are given IV?
1) Ketorolac
2) Parecoxib
171
Which opioid can be used with morphine?
tramadol
172
What medications should be prescribed for post-op?
1) Rescue analgesia
2) Rescue antiemetics
3) Fluids
4) Other medications as indicated
173
