Breathing System Part 1 PDF - AL-Ayen Iraq University

AL-Ayen Iraq University College of Health and Medical Technology Department of Anesthesia breathing system part (1) LECTURE (1&2) PRACTICAL BASICS OF ANESTHETIC EQUIPMENT ( 2)...

AL-Ayen Iraq University College of Health and Medical Technology Department of Anesthesia breathing system part (1) LECTURE (1&2) PRACTICAL BASICS OF ANESTHETIC EQUIPMENT ( 2) By Mushtaq Twayess MSc Anesthesia technologist 3RD STAGE 2024-2025  breathing system: Is a device that conducts gases such as oxygen and anaesthetic agents to the patient and conducts waste gases such as CO2 away. Breathing systems must have three features: 1) Delivery of oxygen. 2) Removal of carbon dioxide from the patient. 3) Delivery of inhaled anaesthetic agents.  Type of breathing system: 1) Open 2) Semi-open 3) Semi-closed 4) Closed systems There are several breathing systems used in anaesthesia. Mapleson classified them into A, B, C, D and E. After further revision of the classification, a Mapleson F breathing system was added. Currently, only systems A, D, E and F and their are commonly used during anaesthesia. Mapleson B and C systems are used more frequently during the recovery period and in emergency situations  Components of the breathing systems: 1. ADJUSTABLE PRESSURE LIMITING (APL) VALVE: This is a valve which allows the exhaled gases and excess FGF to leave the breathing system. It does not allow room air to enter the breathing system. Also called expiratory valve, spill valve and relief valve.  Mechanism of action 1) This is a one-way, adjustable, spring-loaded valve. The spring is used to adjust the pressure required to open the valve. The disc rests on a knife-edge seating in order to minimize its area of contact. 2) The valve allows gases to escape when the pressure in the breathing system exceeds the valve’s opening pressure. 3) During spontaneous ventilation, the patient generates a positive pressure in the system during expiration, causing the valve to open. A pressure of less than 1 cm H2O (0.1 kPa) is needed to actuate the valve when it is in the open position. 4) During positive pressure ventilation, a controlled leak is produced by adjusting the valve dial during inspiration. This allows control of the patient’s airway pressure.  Components of the breathing systems: 2. RESERVOIR BAG: The reservoir bag is an important component of most breathing systems. Components 1. It is made of anti-static rubber or plastic. Latex-free versions also exist. Designs tend to be ellipsoidal in shape. 2. The standard adult size is 2 L. 3. The smallest size for pediatric use is 0.5 L  Components of the breathing systems: 3. TUBINGS: 1. These connect one part of a breathing system to another. They also act as a reservoir for gases in certain systems. 2. They tend to be made of plastic, but other materials such as silicone rubber and silver impregnated bactericidal plastics are available. 3. The length of the breathing tubing is variable depending on the configuration of the breathing system used. 4. The diameter size for adults is 22 mm wide. However, paediatric tubing is 15 mm wide, to reduce bulk. 5. The corrugations resist kinking and increase flexibility, but they produce greater turbulence than smooth-bore tubes.