AMIR SALAH MODERN ANAESTHETIC MACHINE MODERN ANAESTHETIC MACHINE 3 of 4

Performance of Maplesons’ Three distinct functional groups emerge and this include the A, BC, or DEF groups. Three distinct functional groups emerge and this include the A, BC, or DEF groups. 1. Mapleson’ A (Magill) has a valve near face and FGF enters opposite site near RB 2. Mapleson’ B &C valve & FGF inlet located near face. The tubes and RB serve as a blind limb where FG, dead space gas, and alveolar gas can collect 3. Mapleson’ D&E&F ( T-piece) the FGF enters near the patient and excess gas is popped off at the opposite site.

Factors control Mapleson CO 2 conc. REBREATHING 1.FGF rate 1.FGF rate 2.MV 2.MV 3.Mode of ventilation (spont. or controlled) 3.Mode of ventilation (spont. or controlled) 4.TV 4.TV 5.RR 5.RR 6. I/E 6. I/E 7.Duration of expiratory pause 7.Duration of expiratory pause 8.Peak inspiratory flow rate 8.Peak inspiratory flow rate 9.Volume of reservoir tube 9.Volume of reservoir tube 10. Volume RB 10. Volume RB 11.Ventilation by mask or ETT 11.Ventilation by mask or ETT 12.The CO 2 sampling site. 12.The CO 2 sampling site.

SIDE WAY SAMPLING

STREAM ANALYSIS

The relative efficiency of different Mapleson’s with respect to prevention of rebreathing during spontaneous respiration is as follows: The relative efficiency of different Mapleson’s with respect to prevention of rebreathing during spontaneous respiration is as follows: A > DFE >CB A > DFE >CB During controlled ventilation : DFE >BC > A During controlled ventilation : DFE >BC > A Mapleson A B C are rarely used today,but the D E F are commonly employed in form of Bain and Ayre’s circuits. Mapleson A B C are rarely used today,but the D E F are commonly employed in form of Bain and Ayre’s circuits. Mapleson A is the only circuit work with 1 MV while all the others need from 2 to 3 MV Mapleson A is the only circuit work with 1 MV while all the others need from 2 to 3 MV

MAGILL SYSTEM 1921 This is the standard breathing circuit supplied with Boyle apparatus. This is the standard breathing circuit supplied with Boyle apparatus. A two L. bag attached to a bag mount + A two L. bag attached to a bag mount + Long corrugated rubber 42 inch (1.07m)+expiratory valve. Long corrugated rubber 42 inch (1.07m)+expiratory valve. It needs 1 MV or 1 alveolar ventilation (70% of MV )  no rebreathing It needs 1 MV or 1 alveolar ventilation (70% of MV )  no rebreathing Mapleson’s A Mapleson’s A

Ayre’s T-Piece 1937 It is the common pediatric circuit It is the common pediatric circuit It can be expressed as D E or F Mapleson It can be expressed as D E or F Mapleson The original Ayre’s is E, then Jackson-Ree The original Ayre’s is E, then Jackson-Ree Modify it by applying a RB at outlet end in order to be D then this modification is called F by Willis & others in 1957 Modify it by applying a RB at outlet end in order to be D then this modification is called F by Willis & others in 1957