Genral&Local anastheisa Flashcards
بسم الله الرحمن الرحيم وبه نستعين
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Mention aim of general anastheisa
RAASI
Reversible loss of consciusness
Amensia
Analgesia
Skeletal muscle relaxation
Inhibtion of Visceral reflexes
Blanced anasthsia is done by ?
Preanstehtic medication:- HOBA
H1,2blockers Opioides BZs Atropine
for amenisa anxiety and visceral reflexes and anathsies
____________________
IV anasthic for induction
Inhalation ansthetic for maintaence
_____________
Skeletal Muscle relaxant Succinylchlone or NMBs
GA works by?
Inhibtion of midbrain reticular formation
by?
Facilitaion of GABA :
BZs+ Barbit. + halogenated agents Propfol + etomidate
OR
Inhibtion of glutamate NMDA receptor by?
Ketamine+Nitrous oxide
MAC?
Minumun alvolar concentartion
اقل تركيز للغاز المخدر في الحويصلات الهوائية عشان العيان ميترحكش لما يتعرض لمؤثر الم زي فتح جراحي
measuring potency +ED50
MAC is decreased by and inc by?
MAC dec by?
Anathetics BZs + Opioids
A2 blockers clondine
Elderly
Inc potency decreasing ED50
___________________
MAC decreased by?
Drugs increasing Cataechols
Alchol abuse
Increasing ED50 decreasing Potency
High blood gas solubility
or parition cofficient means
slow induction
slow recovery
and vice versa
Halogenated agent
used mainly for Maintaince bu may bu used for indcution
Halotahane
Non irritant smooth pleasnt odor
why halothan + N2o ?
for powerful analgesia
as halothane weak anglesic storong anasthetic
and the N2o is the opposite
Halogenated agent with mdeium rate of Induction and recovery
Halothane
mention adverse effects of halothane
4H+BSCU
Hypotension
HR decreased
Hepatotoxic
Hyperthermia Malignant
_________________-
Uterine relaxation increasing bleeding
Increased ICP due to cerberal VD
Bronchodilator
skeletal muscle relax
Newer Halogenated agents are discovered why?
To Overcome the Hepatoxic effect of halothane
but still
Resp and CVS depression with Maligant Hyperthermia
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Isoflurane
Desfulrane
SevoFlurane
Halogenated agent casuses Ischemia ?
ISOflurane
Halognated agent whichc is respiarotry irritant with purgant odor casing larynospam + Cough?
and may cause (ISCHEMIA)
OR with high PC
ISO flurane
Contraindicated in
Induction
Asthma
Describe PC of ISOFLURANE
It is of high paritotion cofficient so? slow induction slow recovery not for short procedure
Halognated agent whichc is respiarotry irritant with purgant odor casing larynospam + Cough?
WITH low PC
Desflurane
fastest onset and recovery so used in Short procedures
Halogenated that is used for induction of Anastheisa
Halogenated that has no respiratory irritaion
Halogenated that has nephrotoxic effect?
Sevoflurane
___________
Interacting with soda lime forming substance A that is nephrotoxic
Anathetic with Rapid onset and recovery PC=0.47
With Low potency High MAC
Used with other analgesics to minimize thier side effects and increasing analgesic effect
Used in analgesia
in dental clinic -Obsteric analgesia
Nitrous Oxide
N2O
N2O is the safest inhalation agent give reason
__________________
N2O is perferd to Halothane
why?
Less CVS and resp depression
Less Hepatotoxica
Less uterine relaxation
No malignant hyperthermia
Less Effect in ICP
& Skeletal muscle relaxation
List adverse effects of N2O
EHA3b
1-Expand gases in closed spaces increasing pressure in closed spaces
So contraindicated in Bowel obsteruction and Pnemothorax
2-Hypoxia on Recovery
on prolonged use
3-Abuse euphoria
4-Anemia Megaloblastic + Abortion
Mention
Wiedly used IV anasthetic for induction
_________________
Or alone in anastheisa for short procedure
Thiopental
Thiopental redistributed to ?
Skeletal muscles then fatty tissue so ? when readminstered may lead to toxicity due to accumulated amount in fatty tissue
Mention adverse effects of thiopental
Barbituate! ?
Narrow TI with no antidote:
CVS and resp Depression
Acute prophyria
Vasospam+Gangrene
IV anastheic that can cause Vasospam+Gangrene?
Thiopental
IV anasthetic that is used for induction with rapid onset rapid recovery may be used also in IV infusion maintainance
And Has Antiemetic advantage !
Propofol
IV anathetic used in Conscious and deep sedation in ICU ?”
Propofol
Disadvantages of Propofol mention ?
CVS and resp depression +
Pain at site of injection
Dissociative anasteheisa by ?
Ketamine
Mention Advanatages of Ketamine
Bornchodilator so ? prefered in athmatics
Increasing HR and ABP As CVS stimulant
Analgesic: used for minooor procedure
Mention adverse effect of ketamine
-Increasing ICP so CI in head injuires
-Hallucinations and disorientaion on Recovery so proceeded by Diazpam
Benzodiazepine lkie
,,,,,,and,,,,and,,,,,
used in anastheisa especially ,,,,,, due to its ,,,, and ,,,,,and,,,,,,
________________
indications :
1-
2-
3-
____________________
Advantage?
Midazolam
Lorazepam
Diazpema
_____________
Midozolam
Short onset and duration and less irritant
___________________
Conscious sedation
preanasthetic
Balanced anastheisa
___________________
Flumzenil as antidote
gopioids and propfol may be combined in …. anastheisA
IV
What is the mechanism of Local anastheisa
ان الجزء المحب للدهون للمخدر الموضعي يعدي غشاء الخلية العصبية ويقفل من جوا بوابات الصوديوم ويمنع جهدالحركة انه بتولد وبالتالي يمنع انتقال النبضات العصبية في مسارات الألم
اذكر العوامل المؤثرة علي حساسية العصب للمخدر الموضعي
1-LA is more effective in rapid firing nerves
2-More effective on small nerves of Pain &temperature
chemical structure of LA ?
(Aromatic + ( Ester-Amide ) + Amine )
Compare between Esters &Amide LA MDLE
Metabolism
duration
liable to
expanison of duration
________________
Esters like Procaine - benzocaine -Cocaine
Amides lkie Lidocaine bupivacaine
Esters hydolysed by pseudocholin esterases
but Amide by Liver metabolism
_________________
Esters shorter duration due to palsma esterases but amide longer duration due to liver
________________
Esters liable to allergy (analgue with PABA)
But Amide liable to Systemic Toxicity
_____________________
Esters duration increased in genetic defect on enzyme but Amide duration increased in liver diseases
Examples to LA
Procaine from esters short acting may extends to one hour
Lidocaine intemediate 2 hours
Bupivacane Long 3 hours
Mnetion Factos affecting Activity of Lcoal anasthetics
p2L
-Plasma protein binding
Bubivacne > lidocaine so longer acting
-Lipid Solubility Bubivance 7 times more potent than lidocaine
-PKa of drug as the less basic the more non ionized extracellular the more rapid tha action is as Bupivacne >lidocaine
LAs are weak,,,,,,, Pka from ,,,,,to ,,,,,,,
Only,,,,,,, form can cross the nerve membrane to the site of action
ECF PH= ?
IC = ?
bASES (7,7-9
Non ionized
______________
7,35
6-7,4
What happens in increased ECF acidity for LAs?
What happens in infection in relation to LAs?
What Happes in Repeated lidocaine ?
increasing ECF acidity
________________________
Incrasing IOINZED
Decreasing Non ionized
so few inoized intracellular so less action
how to improve local anasthetsia?
By adding NaHCO3 to alkalnization of the media of ECF
Increasing NON ionized form of the LA so increased Ionized Intracellulaet potenitating the blockade
GR for using vasoconstrictors with LAs?
LAs except cocaine cause VD of blood vessels increasing absorption of LAs in blood causing systemic toxicity
_________________
Vasoconstirtors prevents absorption of LAs preventing Systemic toxicity
as Epinphernie CI in finger toes nose gangrene
Felypressin perefered to EP in cardiac patients
LA in surface anasthesia ?
applied to skin and muscous membrane
LA in infiltartion anasthesia ?
Submucosal
subcutanuous
dentist
LAs nerve block ?
in denistiry and surgery
Inject clost to trunk blocking all branches
used in surgery of abdomen , pelvis and legs when general anasthesia in contraindicated
spinal and epidural anastheisa
Injection in subarachanoid space below L2 Acting on spinal cord and spinal roots with immediate onset?\
Mention side effects
Spinal anasthesia
side effcets:HSI
Headache (CSF Leakage and traction)
Hypotension due to sympathatic block
Spinal root injury
Infection
Injection outside dura blckong spinal roots onset 10 minutes delay
Epidural anasthesia\in
painless labot
Injection outside dura blckong spinal roots onset 10 minutes delay
Epidural anasthesia\in
painless labor
Mention adverse effect of Local anasthertics
1-CNS :
Numbness -restlessness
tremors - consulsions coma death
2-Neurotoxicity: spinal cord or trunks as paraplegia or parathesia in spinal and eipdural anathesia
3-CVS decrasing HR and ABP
Bbpivacin is extermely cardiotoxic in high doses
4-VCs increasing BP may peripitate arryhtmia
5-allergy: Esters analogue to PABA
Lidocaine is CI with ?
Propranolol
as propranolol reuces the hepatic blood flow decrasing clearance of lidocaine casuing toxicity
Lidocain/EP CI with Propranolo ?
As propranolo blockinb2 so alpha is not opposed casuing sever VC and severe hypertension
MAOI &TCAs are CI with Lidocaine/EP ? WHY
MAOI and TCAs increasing CA + EP = hypertensice crisis
الله نزل أحسن الحديث كتابا متشابها مثاني تقشعر منه جلود الذين يخشون ربهم ثم تلين جلودهم وقلوبهم إلي ذكر الله ذلك هدي الله يهدي به من يشاء
