GENERAL ANAESTHESIA

24 Pages·2012·1.16 MB·English

GENERAL
ANAESTHESIA
Jozef Firment, MD PhD
Department of
Anaesthesiology & Intensive Care Medicine
Šafárik University Faculty of Medicine, Košice
A
I
S
E
H
DEFINITION
T
S
E
A
N
A
• (an) aisthetos = (un) perception

L
A
R
E
N
• general anaesthesia = „narcose“
E
G
• regional anaesthesia = local
tn
e
m
r
iF
2
A
I
S SURGICAL STRESS MAP
E
H
T
Barash, 1997
S
E
Theoretical Plasma Drug
A
Concentration for Adequate
N
A Anaesthesia

L
A Intubation
R
E
N
E Incision

G n
o Mount
r
i
o t
a Lake
Surgery
e r Recovery
s t
n Prep.
n
e Plains
o
c
p
n
Anxiety
s Peritoneal Bowel/
o
e
c
R Mound Traction Vascular ICU
a

s m
s Clamping Highlands
Sleep River
e s
r a tn
t l e
S P m
r
iF
Duration of Surgery
3
A
I
S
E PHARMACO-ANAESTHESIA
H
T
S
METHODS
E
A
N
A

L • Inhalational anaesthesia ... VIMA
A
R
E • Intravenous anaesthesia... TIVA
N
E

G
• Intramuscular
• Rectal

• Combined anaesthesia tn
e
m
r
iF
4
A
I BASAL PARTS OF GA
S
E
H
T
S
E BIS Monitoring
A
N
Consciousness/Hypnosis
A

L
A
R
E
N
E
G
Balanced
Anaesthesia
Muscle
Analgesia relaxation/
Areflexia
Hemodynamic Peripheral
tn
Monitoring Nerve Stimulator e
m
r
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Monitoring
Monitoring Anaesthetic Endpoints
5
A
CIRCULATORY EFFECTS
I
S
E
H
INHAL. ANAESTHETICS
T
S
E
(Barash, 1997)
A
N
A •  BP according to dose (vasodiltion,  C.O.,

L
cardiodepresion,  sympat. activity)
A
R
•  consumption O about 10-15%
E
2
N
•  blood flow in liver, kidneys and gut,
E
G
 in brain, muscles & skin
• N O SVR, PVR and BP,  C.O.
2
• Sensibilisation myokardium to catecholamins:  in
children, HAL > ENF > ISO > DES > SEV (more in
CO , more with thiopental)
2
• No influence to pacemaker functions
tn
e
m
• No coronary steal efect in man r
iF
6
A
RESPIRATORY EFFECTS
I
S
E
H INHAL. ANAESTHETICS
T
S
E (Barash, 1997)
A
N
A
• All  V and bronchodilational effect

L T
A
• Bloc histamin effects on bronchi – bronch.
R
E
N asthma treatment: HAL, SEV
E
G
• Respiratory depresion : N O>HAL>ISO>DES
2
• No influence to hypoxic pulmonary
hypertension

• Up to 3x increase effects of musclerelaxants tn
e
m
r
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A
CNS EFFECTS OF
I
S
E
H
INHAL. ANAESTHETICS
T
S
E
(Barash, 1997)
A
N
•  intelectual functions, HAL for 2-8 days (B?)
A

L
A •  intensity of cerebral metabolism (CMRO ):
R 2
E ISO > EFL>HAL.
N
E • Vasodilat. cerebr. a. &  pressure CSF:
G
HAL>ISO=DES=SEV,
• HAL > ISO influence production & absorbtion CSF
• Light hypocapnia - lower ICP in ISO than HAL
• Autoregulation to CO is more blocked by HAL than
2
ISO
tn
e
m
• Epi EFL
r
iF
8
A
I
S
E TOXICITY
H
T
S
E
A
• HAL = hepatotoxicity (imuno, repeated
N
A
expositions)

L
A
• N O = hematotoxicity „perniciose“
R
2
E
N anaemia
E
G
• In septic pat. weakening Ne and Le
functions
• Change platelets functions
• Myometrium relaxation – bleeding
during C.s. (HAL > 0,5, ISO > 1,0)
tn
e
m
Barash, 1997
r
iF
9
A
I DISTRIBUTION COEFF.
S
E

H ANAESTHETICS (BLOOD / GAS)
T
S
E
A

)
N s
a
A g
:
L Less solubility = faster onset
d 3
A o
R o 2.5
l
b
E (

N tn 1.8
2
e
E
i
c
G i 1.43
f
f
e
o
c 1
0.65
n
o 0.45 0.47
i
t
u
b
i
r
t
s
i Desflurane Nitrous Sevoflurane Isoflurane Enflurane Halothane
D
Oxide
tn
e
m
r
iF
Miller. Anesthesia. 4th ed. Churchill Livingston, 1994; Data on file, Abbott Laboratories Inc.
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