The second law of thermodynamics says that the entropy of the universe (or any isolated system therein) is increasing; i.e., the energy of the universe is becoming more uniformly distributed. It is often noted that the second law indicates that nature tends to go from order to disorder, from complexity to simplicity.
Small-bore catheters and Heimlich valves have been successfully used in. the treatment of pneumothoraces in several studies.4,5 The thoracic vent. (see Figure 1) is a minimally invasive device for the treatment of. pneumothorax. It consists of a polyurethane catheter connected to a. plastic chamber containing a one-way valve.
Principles of artiï¬cial ventilation Tim Gould J M A de Beer Abstract Ventilators are commonly used in the operating theatre and in the ICU to deliver mechanical ventilation to the lungs. In the operating theatre, ventilation is given to anaesthetized and often pharmacologically para-lysed patients with predominantly normal lungs. These ventilators are