On some physiological aspects of the position of Fowler are contrary to the Trendelemburg position. In the lungs, Fowler position increases the residual functional capacity and decreases the work of spontaneous ventilation. In the circulatory system, preload decreases, increases sympathetic tone, as well as heart rate and peripheral vascular resistance.
TEMPERATURE:
In patients undergoing laparoscopic cholecystectomy, the body temperature decreases 0.3 ° C for each 50 L of CO2. Factors causing the decrease in body temperature, are insufflated CO2, the inability to muscle to produce heat, peripheral vasoconstriction, or abolition of the thermoregulatory skin mechanism.
Commonly used general anesthesia balanced for the anaesthetic management of patients who perform laparoscopic cholecystectomy. General anesthesia offers surgical conditions due on the one hand, that used relaxing neuromuscular, which provides muscle relaxation, which allows the use of low inflation pressures and prevent unexpected movements of the patient.
Intubation of the airway, on the other hand, protects the Airways and decreases the incidence of bronco aspiration by regurgitation of gastric contents. Controlled ventilation can also be provided to prevent the hypercapnia and hypoxemia. On the other hand, the placement of a tube is required occasionally nasogastric tube in order to decompress the stomach to reduce the risk of visceral perforation during the introduction of the trocar and decrease the risk of bronco aspiration.
However, general anesthesia has its disadvantages, such as: prolonged recovery, additional stress to the patient with severe heart or lung disease, higher incidence of side effects such as nausea and vomiting, a high cost and deficiency in the control of postoperative pain.