Covidien INVOS 5100C, Руководство оператора

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B-1
B Clinical Studies
B.1
Overview
This chapter provides information on two clinical studies using the INVOS™ regional saturation
patient monitoring system. A reference bibliography containing additional clinical studies is
available on Covidien’s website (www.covidien.com) or by contacting Covidien’s customer
service department.
An adult volunteer study was performed comparing the regional oxygen saturation (rSO
2
) from
the INVOS™ system to blood sample analysis in 20 volunteers (hypoxia study). No adverse
events attributable to the INVOS™ system were reported during the study. A second study also
compared the rSO
2
from the INVOS™ system to blood sample analysis in 22 patients with con-
genital malformations of the heart and great vessels in the pediatric cath lab (pediatric study).
No adverse events attributable to the INVOS™ system were reported during the study.
B.2
Hypoxia Study
The hypoxia study compared the rSO
2
as reported by the INVOS™ system to the “field” satura-
tion (fSO2) calculated from arterial and jugular venous blood oxygen saturation measurements
at five levels of oxygen saturation and two levels of inspired CO
2
. Based on the assumption that
cerebral tissue contains arterial and venous blood in a 1:3 ratio, fSO
2
was calculated as:
fSO
2
= (0.25 X SarterialO
2
) + (0.75 X Sjugular veinO
2
)
The 20 volunteers included: 19 with light and 1 with dark skin; 12 males and 8 females; age 20
to 36 years, with a median of 25 years. One data point was excluded from analysis due to delays
in blood sampling caused by catheter problems.
Methods : Blood samples were obtained from the right internal jugular bulb and the radial
artery. An INVOS™ adult regional saturation sensor was placed on the right forehead. Subjects
breathed controlled gas mixtures in a predefined sequence of 4- and 5- minute intervals to
attain five levels of arterial O
2
saturation (74% to 100%). This sequence was performed twice at
two different CO
2
levels (4-7 mmHg increase) intended to raise cerebral blood flow and evalu-
ate the ability of the INVOS™ system to reject noncerebral data.