The SensorMedics High-Frequency Oscillatory Ventilator is a patented

high-frequency High frequency (HF) is the ITU designation for the range of radio frequency electromagnetic waves (radio waves) between 3 and 30 megahertz (MHz). It is also known as the decameter band or decameter wave as its wavelengths range from one to ten ...

(>150 R_f)

mechanical ventilator A ventilator is a piece of medical technology that provides mechanical ventilation by moving breathable air into and out of the lungs, to deliver breaths to a patient who is physically unable to breathe, or breathing insufficiently. Ventilators ...

designed and manufactured by SensorMedics Corp. of

Yorba Linda, California Yorba Linda is a suburban city in northeastern Orange County, California, United States, approximately southeast of Downtown Los Angeles. It is part of the Los Angeles metropolitan area, and had a population of 68,336 at the 2020 census. Yor ...

. After a series of acquisitions, Vyaire Medical, Inc. marketed the product as 3100A/B HFOV Ventilators. Model 3100 (later 3100A) received premarket approval from the United States

Food and Drug Administration The United States Food and Drug Administration (FDA or US FDA) is a List of United States federal agencies, federal agency of the United States Department of Health and Human Services, Department of Health and Human Services. The FDA is respon ...

(FDA) in 1991 for treatment of all forms of

respiratory failure Respiratory failure results from inadequate gas exchange by the respiratory system, meaning that the arterial oxygen, carbon dioxide, or both cannot be kept at normal levels. A drop in the oxygen carried in the blood is known as hypoxemia; a rise ...

neonatal An infant or baby is the very young offspring of human beings. ''Infant'' (from the Latin word ''infans'', meaning 'unable to speak' or 'speechless') is a formal or specialised synonym for the common term ''baby''. The terms may also be used to ...

patients. In 1995, it received pre-market approved for Pediatric Application with no upper weight limit for treating selected patients failing on conventional ventilation.

3100A

The 3100A model is used for infants and children under 35 kilograms (<35 kg).

3100B

The 3100B model is used for all other people weighing more than 35 kilograms.

Controls and settings

Bias flow

Adjusting bias flow affects mean P_aw. Lowering bias flow may decrease the work of breathing and facilitate weaning. ; Typical ranges *Premature 8–15 LPM *Near-term 10–20 LPM *Small child 15–25 LPM *Large Child 20–30 LPM

Adjust

This control sets the mean airway pressure, directly affecting lung volume and oxygenation. The initial setting is slightly higher than the mean airway pressure for conventional ventilation.

Power

Piston displacement is controlled by the power setting. Power changes ventilation and thereby changes blood

PaCO2 ''p''CO2, pCO2, or P_\ceis the partial pressure of carbon dioxide (CO2), often used in reference to blood but also used in meteorology, climate science, oceanography, and limnology to describe the fractional pressure of CO2 as a function of its c ...

levels. ; Typical values Start with a power of 2.0 and adjust for chest wiggle to the umbilicus.

Inspiratory time %

T_i% is the percentage of time allotted for inspiration. Once this value is set, it rarely needs to be changed. ; Typical values *33% is recommended by the manufacturer for almost all applications. *Up to 50% is recommended in situations where lung recruitment is necessary. * Any Inspiratory Time above 33% can cause air trapping and lead to barotrauma. Setting the Mean airway pressure 1–2 cm of h2O above the set MAP for a few minutes, then weaning back down to the original MAP can recruit alveoli safely.

Frequency

Frequency (R_f) is the number of breaths in one second, expressed in hertz (hz). One hertz is equal to 60 breaths per minute (R_f) . ;Typical values and ranges *The smaller the patient, the higher the frequency. *The larger the patient, the lower the frequency. ; Changes in frequency *Decrease in frequency = increased

tidal volume Tidal volume (symbol VT or TV) is the volume of air moved into or out of the lungs during a normal breath. In a healthy, young human adult, tidal volume is approximately 500 ml per inspiration or 7 ml/kg of body mass. Mechanical vent ...

. *Increase in frequency = decreased tidal volume.

Problems

Since neither the 3100A or the 3100B measure actual tidal volumes, it is impossible to wean with precision;{{cite journal, vauthors=Scott CJ, McGeorge AD, Hancock SW , title=Failure of adequate ventilation using Sensormedics 3100A High Frequency Oscillatory Ventilator. , journal= Paediatr Anaesth , year= 1997 , volume= 7 , issue= 5 , pages= 432 , pmid=9308072 as a result, some clinicians find it problematic to use these machines for oscillatory ventilation.

References

Mechanical ventilation Respiratory therapy Medical equipment Pulmonology