Speaking roughly, normal levels of thyroid-stimulating hormone (TSH) are in the range of 0.4 to 4.0 mIU/L. However, each laboratory and test manufacturer identifies its own normal TSH range.
A common strategy is to combine SIMV with an additional ventilator mode known as pressure support ventilation (PSV) (Fig. 4). In this situation, inspiratory pressure is added to spontaneous breaths to overcome the resistance of the endotracheal tube or to increase the volume of spontaneous breaths.
There are other machines that are similar to a CPAP ventilator, such as a bi-level positive airway pressure machine. The difference between CPAP and BiPAP is that the CPAP provides continuous air pressure, and the BiPAP provides a different level of pressure for inhaling than for exhaling.