Pressure Measurement

Hg or H20 Barometer Measures [blank_start]Barometric[blank_end] Pressure Hg – read at the [blank_start]TOP[blank_end] of meniscus H2O – Read at the [blank_start]bottom[blank_end] of meniscus Mercury Spill – Wipe up ASAP and dispose of in [blank_start]vacuum[blank_end] sealed contained If air is not evacuated from barometer it will read [blank_start]low[blank_end].

Inductive Plethysmography Bands containing [blank_start]Teflon[blank_end] coated wire or [blank_start]pressure[blank_end] sensitive semiconductors are wrapped around [blank_start]chest[blank_end]/[blank_start]abdomen[blank_end] Used to monitor chest motion and Vt in [blank_start]PSG[blank_end]

Aneroid Manometer Used to measure [blank_start]MIP[blank_end]/[blank_start]MEP[blank_end] and [blank_start]BP[blank_end]

Pressure Transducers Used to convert one of [blank_start]energy[blank_end] to another Most common [blank_start]strain[blank_end] gauge transducer Used in [blank_start]hemodynamic[blank_end] monitoring to convert [blank_start]analog[blank_end] to digital.

BP manometer Best Method – [blank_start]arterial[blank_end] catheter w/pressure transducer Measures: [blank_start]Systolic[blank_end], [blank_start]diastolic[blank_end], [blank_start]mean[blank_end] arterial pressure

Gas Delivery Systems Blenders: to deliver [blank_start]precise[blank_end] O2 Equalizes [blank_start]inlet[blank_end] pressure of air and o2 Precision metering device – [blank_start]proportioning[blank_end] valve Low [blank_start]pressure[blank_end] alarm Can be used with a nonrebreather mask to deliver precise O2 Flowmeters Controls gas flow to patient Flow indicated by [blank_start]ball[blank_end] Different gases will cause [blank_start]inaccurate[blank_end] readings

[blank_start]Integrator[blank_end] – Process in which flow is divided into very small intervals. Flow is volume/time – end result is volume. [blank_start]Differentiation[blank_end]- Device that provides reverse of integration. Flow is obtained from volume signals Data Backup- Temporary Storage, permanent patient files, database storage [blank_start]Data[blank_end] Interface – Allows for both access to data and control of equipment during testing 12 bit converters – used most for volume and flow measurements Converter speed – important for tests that require [blank_start]rapid[blank_end] signal changes like FVC Software – contains [blank_start]instructions[blank_end] stored in memory of computer. Most software contains interpretation programs that utilize algorithims Mass Storage Devices – Hard Drives, stores lots of info CPU – Performs most functions in software [blank_start]Resolution[blank_end]- Smallest change that can be measure by computer. Calculated via: Volume range (liters), Signal range (volts), A/D converter (bits