Anaesthesia

Inducing an unconscious state where the patient is :

-Unaware

-Pain-free

-Immobile

-Memory-free

Anaesthesia

Induce it Vascular system

(Syringe )

Maintain it Pulmonary system

(Anesthesia machine )

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Anaesthesia )for adults(

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Anesthesia Ventilator Vaporizer

Anesthesia oversimplification

Vaporizers

Flow controller

Pressure gages

O2 flush

Drawers

Flow meters

Vent. monitor

Ventilator

CO2 removal

AGSS

Anaesthesia / Main parts

Main parts

Ventilator

During anesthesia muscles relax)including lung diaphragm(

Lung diaphragm: the muscle who establish positive and negative pressures in order to inhale and exhale air.

Why ventilator?

Ventilator job: to push gas )containing O2, N2O…etc( into the lungs.

OVER simplification!

We can control: volume of gas, speed, frequency, pattern, pressure inside the lung …etc.

Why ventilator?

Manual or via ventilator

Ventilation during anaesthesia

Ventilator

1 -Gas driven

2- Electrically driven, electronically controlled

b( Electronically controlled

a( Pneumatically controlled

Ventilator types:

Ventilation via Ventilator

Piston motor

ValveValve

Bellow

Electrical ventilator

Piston motor

ValveValve

Bellow

Piston down )gas in(

Electrical ventilator principle

Piston motor

ValveValve

Bellow

Piston up )gas out(

Electrical ventilator principle

Electrical ventilator / real look

Used sometimes at the end of anesthesia or incase of ventilator failure

Drawing for illustration )valves within ventilation part(

valvevalve

Elastic bag )rubber, silicon…etc(

Ventilation via bag )manual(

valvevalve

Elastic bag )rubber, silicon…etc(

Fresh gas from machine

Ventilation via bag )manual(

valvevalve

Fresh gas to patient

Force by hand

Elastic bag )rubber, silicon…etc(

Ventilation via bag )manual(

Main parts

Vaporizer

Vaporizer job: to load the gas with anesthetic agent.

OVER simplification!

We can control: type and dose of anesthetic agent.

Vaporizer oversimplification

Halothane, Enflurane, Isoflurane, Sevoflurane & Desflurane

Each one has its own properties.

Example:Sevoflurane and halothane : easy to inhale Desflurane : very irritating to inhale , shorter duration of action.

Halothane decrease the heart rate and blood pressure Desflurane increase the heart rate and blood pressure

Vaporizer types

Anesthetic agent Lungs Brain Blood

Lungs Brain Blood

During Anesthesia:

After Anesthesia:

((Most important feature ))Reversible effect

Feature of anesthetic gases

Summery: fresh gas will flow through the anesthetic agent chamber and enriched with anesthetic agent vapors

IN OUT

Vaporizer internal construction

Main parts

Flow controllers

Anesthetic gas

O2 N2O Anesthetic agent Medical Air

Relaxes the musclesProduces an

unconscious state To lower N2Oconcentration

O2 concentration must not be lower than 21% of the total inhaled gas )this is achieved by Anti-hypoxic device(

Anesthetic gas content

N2OO2

The device that prevent delivery of O2 lower than 21-25% of fresh gas

Anti-hypoxic device / principle

Main parts

Flow meters

Glass tubes

Function :control the amount

of gas )Oxygen, Nitrous & Air( in the

fresh gas )L/min(

Flow meters

Main parts

AGSS(In the back)

Exhaled gas does contain anesthetic agent.

Doctors and nurses surrounding the patient will be subjected to anesthetic gases as well.

How to prevent this?Suck the exhaled gas outside the operating room.

Inhalation Exhalation

Anesthetic Gas Scavenging System

AGSS wall outlet AGSS Hospital pipeline system

Discharge at the hospital roof

AGSS topology

CO2 removal

CO2 removal

Anesthetic gases:

1( Expensive

2( Unwelcome to the surrounding area

Solution: Return exhalation back to patient!

Inhalation Exhalation

The exhaled gas will be returned back to patient after being passed through ‘Soda lime’ for CO2 removal

Open / Closed / Semi-Closed systems

CO2

Anesthetic agent O2 + N2O

Soda lime

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Soda lime

The main components of soda lime are

- Calcium hydroxide, Ca)OH(2 )about 75%(

- Water, H2O )about 20%(

- Sodium hydroxide, NaOH )about 3%(

- Potassium hydroxide, KOH )about 1%(

Chemical reaction:

CO2 + H2O → H2CO3

H2CO3 + 2NaOH → Na2CO3 + 2H2O + Heat

Na2CO3 + Ca)OH(2 → CaCO3 + 2NaOH

Ca)OH(2 )heat( → CaO + H2O

Soda lime principle

Systems:

1( Open: no gas is returned to patient

2( Closed: no gas is released from patient

3( Semi-Closed: part of the gas will be released from patient.

Inhalation Exhalation

Open / Closed / Semi-Closed systems

ECG Cardiac system function

NIBP / IBP Vascular system function SpO2 O2 concentration etCO2 CO2 concentration

Agents Anesthetic agent concentration

BIS level of consciousness

Monitored parameters during anesthesia

Provides a direct measure of the effects of anesthetics and sedatives on the brain

EEG signal processing numerical number to show the level of sedation

Safer anesthesia / BIS® monitoring

Anaesthesia / Fabius plus

Anaesthesia / Fabius plus

One of latest equipment data sheet overviewAnaesthesia / Fabius plus

Anaesthesia / Fabius plus

Anaesthesia

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