Final answer:
Spirometry is used to measure lung function, not blood pressure. It is necessary to use a sphygmomanometer to measure blood pressure. Provide the spirometry results if interpretation is needed.
Step-by-step explanation:
In order to calculate Systolic Blood Pressure (SBP), you need to have the spirometry reading that was given to you. However, spirometry is actually used to measure lung function and not blood pressure. Blood pressure is usually measured using a device called a sphygmomanometer. If you need help interpreting a spirometry reading, please provide the spirometry results and I would be happy to assist you further.