O 2 and CO 2 are exchanged by diffusion of the gases across the alveolar membrane. Diffusion is based on the concept that solutions of a greater concentration will pass or move into solutions of a lower concentration. The effectiveness of ventilation is evaluated by the level of CO 2 in the blood. The respiratory rate is primarily controlled by the pons and medulla portions of the brain. The normal resting respiratory rate in adults is 12 to 20 respirations a minute.
Several factors can have a profound effect on a person's respiratory rate.
Table 1 lists possible factors that may alter the rate of respiration. That May Alter Respiratory Rate Body Temperature Respiratory rate may increase with fever. Drugs and Medications Respiratory rate can increase or decrease depending on the physiologic action of the medication. Pain Respiratory rate may increase with pain. Emotion Respiratory rate may increase with distress.