Local Anesthetics And General Anesthetics

Question 1

What is local anesthetics

Answer 1

Causes loss of sensation and pain in local areas of the body

Question 2

Stages of anesthesia

Answer 2

*Stage 1- (induction ) a period where patient goes from state of consciousness to a stage of unconsciousness
*stage 2: (Excitement )depression of inhibitory neurons in CNS causes involuntary muscle excitation,increased heart rate,blood pressure
*stage 3 :(Surgical anesthesia )gradual loss of muscle tone and reflexes,patient is fully unconscious and has regular breathing ideal for surgery
*stage 4( medullary paralysis) respiratory and cardiovascular failure occurs which can lead to death if patient is not revived

Question 3

Mechanism of action of general anesthesia

Answer 3

*Actions on general anesthesia on reticular formation and thalamus leads to loss of consciousness
*Action of hippocampus,amygdala and prefrontal cortex causes Amnesia
*Action on spinal cord leads to immobility and analgesia

Question 4

Groups of general anesthetics(intravenous group)

Answer 4

• propofol
  -Barbiturates
  -Etomidate

Question 5

Which phase is intravenous group used and what kind of action

Answer 5

induction phase and they commonly cause loss of consciousness
-they act on GABAa for inhibitory action opening of chlorine channels leading to inhibition

Question 6

Side effects of intravenous group

Answer 6

*etomidate can cause adrenal suppression and transient skeletal muscle movements (myoclonus
*propofol causes respiratory depression and hypotension
*barbiturates can cause sleep apnea,bronchospasm cough, and repetitive depression

Question 7

2nd group of general anesthesia

Answer 7

*Ketamine(intravenous )
*inhalation) agents
-Nitrous oxide
-xenon
-cyclopropane

Question 8

2nd group is used in which phase of anesthesia

Answer 8

Maintenance phase

Question 9

2 group action is on which receptor

Answer 9

NMDA-N-methyl D- aspartate receptor

Question 10

Where is NMDA located

Answer 10

Spinal cord and they are crucial in modulation and processing when neurotransmitter glutamate binds to NMDA

Question 11

Mechanism of action of 2nd group ketamine,nitrous oxide,xenon and cyclopropane

Answer 11

They inhibit NMDA receptors and stop or decrease the neurotransmission of pain

Question 12

Adverse effects 2nd group (ketamine,nitric oxide,xenon)

Answer 12

*Ketamine can cause hypertension,tachycardia and hypersalivation emergence phenomena (hallucinations,delirium vivid dreams
*Nitrous oxide and cyclopropane causes dizziness and nausea

Question 13

3rd group of general anesthesia include(halogenated volatile anesthetics)

Answer 13

*Halothane
*Enflurane
*Isoflurane
*Sevoflurane
*Desflurane

Question 14

Mechanism of action of 3 group anaesthesia

Answer 14

They actively cause immobility
They inhibit NMDA receptors

Question 15

Side effects of 3rd group of general anesthesia include

Answer 15

*halothane causes cardiac arrhythmias and hepatotoxicity
*sevoflurane may cause renal toxicity
*hypotension

Question 16

What is local anesthesia

Answer 16

They produce transient loss of sensory perception especially of pain in the local area of the body without producing loss of consciousness

Question 17

Mechanism of action of local anesthetics

Answer 17

*They bind to a specific receptor at the opening of the voltage gated sodium thus preventing sodium influx ,this in turn prevents the initiation and conduction of action potential
*This leads to loss of sensation in the area supplied by the nerve

Question 18

Give 5 drugs that are local anesthetics

Answer 18

*Bupivacaine
*lidocaine
*procaine
*mepivacaine
*Ropivacaine

Question 19

Systemic toxicity of local anesthetics

Answer 19

Blurry vision
Seizures
Arrthymias