Related Experiment Video
Updated: Aug 12, 2026
09:02
Percutaneous Hepatic Perfusion (PHP) with Melphalan as a Treatment for Unresectable Metastases Confined to the Liver
Published on: July 31, 2016
The parallel Lack anaesthetic breathing system
Anaesthesia
|May 1, 1993
Summary
The parallel Lack system, a modified Mapleson A circuit, effectively prevents rebreathing during spontaneous ventilation in lung models, volunteers, and patients. Its performance is comparable to the Magill attachment, ensuring safe anesthesia delivery.
Area of Science:
- Anesthesiology
- Respiratory Physiology
Background:
- The Mapleson A system is a common anesthetic circuit.
- Modifications aim to improve performance and safety.
Purpose of the Study:
- To evaluate the parallel Lack system, a novel Mapleson A modification.
- To determine its efficacy in preventing rebreathing during spontaneous ventilation.
Main Methods:
- Assessed fresh gas flow requirements to prevent rebreathing.
- Utilized a lung model, conscious volunteers, and anesthetized patients.
- Defined rebreathing using ventilation changes, end-expired CO2, and inspired CO2 tension.
Main Results:
- Rebreathing onset occurred at a fresh gas flow to minute ventilation ratio (VF/VE) of approximately 0.75 in lung models and volunteers.
- Results were comparable to the Magill attachment.
- The parallel Lack system demonstrated Mapleson A functionality in anesthetized patients.
Conclusions:
- The parallel Lack system functions as a Mapleson A circuit.
- It effectively prevents rebreathing during spontaneous ventilation.
- Breathing resistance is comparable to the Magill system.
Related Concept Videos
01:20Inhalational Anesthetics: Overview
Inhalation anesthetics are drugs that induce general anesthesia upon inhalation. They work by increasing the sensitivity of GABAA receptors or inhibiting NMDA receptors, leading to a decrease in central nervous system activity. The depth of anesthesia can be rapidly adjusted by changing the concentration of the inhaled gas. Some common examples of inhalational anesthetics include volatile liquids like isoflurane, desflurane, sevoflurane and gases like xenon and nitrous oxide. Isoflurane, a...
01:26Oxygen Delivering System I: Nasal Cannula and Face Mask
The human body requires oxygen to function, and when the natural process of respiration is hindered, external devices, including the following, are needed to help deliver this vital gas.
Nasal Cannula
A nasal cannula is a lightweight tube split at one end into two prongs and placed in the nostrils. It is typically used to deliver low to medium levels of oxygen.
Suggested flow rate: The suggested flow rate for a nasal cannula typically ranges between 1 and 6 L/min.
Oxygen percentage setting:...
Nasal Cannula
A nasal cannula is a lightweight tube split at one end into two prongs and placed in the nostrils. It is typically used to deliver low to medium levels of oxygen.
Suggested flow rate: The suggested flow rate for a nasal cannula typically ranges between 1 and 6 L/min.
Oxygen percentage setting:...
01:16Oxygen Delivering System II: Venturi Mask and Transtracheal Oxygen
Oxygen therapy is a pivotal aspect of medical care, particularly for patients with respiratory ailments. Two prominent oxygen-delivering systems include the Venturi mask and the transtracheal oxygen catheter.
Venturi Mask
The Venturi mask, named after the Venturi effect, is designed to deliver precise oxygen concentrations. It consists of a large tube with an oxygen inlet that narrows down, causing a pressure drop that pulls air in through adjustable side ports. The mask is a lightweight,...
Venturi Mask
The Venturi mask, named after the Venturi effect, is designed to deliver precise oxygen concentrations. It consists of a large tube with an oxygen inlet that narrows down, causing a pressure drop that pulls air in through adjustable side ports. The mask is a lightweight,...
01:23Mechanical Ventilation III: Noninvasive Ventilation
Noninvasive positive-pressure ventilation (NIPPV), continuous positive airway pressure (CPAP), and bilevel positive airway pressure (BiPAP) are essential methods in respiratory care. These ventilation techniques offer unique benefits for patients with various respiratory conditions, providing adequate support without requiring intubation. Let's explore how each method is crucial in improving patient outcomes and enhancing respiratory therapy.
Noninvasive Positive-Pressure Ventilation (NIPPV)
Noninvasive Positive-Pressure Ventilation (NIPPV)
01:14Ventilatory Modes
Mechanical ventilators are life-saving devices that support or replace spontaneous breathing. They deliver breaths to patients through varying methods known as ventilator modes. Understanding these modes is critical for healthcare providers managing patients with respiratory failure.
There are three ventilatory modes: full support, partial support, and spontaneous. These are described below.
Full Support Modes
Full support modes include controlled mechanical ventilation, continuous mandatory...
There are three ventilatory modes: full support, partial support, and spontaneous. These are described below.
Full Support Modes
Full support modes include controlled mechanical ventilation, continuous mandatory...
01:22Cardiopulmonary Resuscitation II: ACLS Airway Management
Airway management is a key skill in emergency and critical care settings, as maintaining a clear airway is essential for adequate oxygenation and ventilation.Head Tilt-Chin Lift TechniqueThe head tilt-chin lift maneuver is an essential technique primarily used in patients without suspected cervical spine injuries. To perform this maneuver, one hand is placed on the patient’s forehead, and gentle pressure is applied backward to tilt the head. The fingertips of the other hand are positioned under...