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.
This pressure is typically set slightly higher than atmospheric pressure to prevent atelectasis, decrease inspiratory work of breathing, or improve gas exchange depending on the clinical scenario. This positive end-expiratory pressure (PEEP) is generated by a resistor in the exhalation port of the ventilator (Fig. 2).
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.