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.
Ventricular assist devices, or VADs, are used to treat heart failure. Also known as heart pumps, VADs are mechanical pumping devices designed to help the heart pump more blood. They work by taking blood from the heart and pumping it to the rest of the body, thus taking the burden off the heart.