Co₂ Measurement Practicalities; Ventilation Management - GE CARESCAPE ONE User Manual

CARESCAPE ONE User Manual DRAFT 26 October 2017
1. Expiration
2. Cardiogenic oscillations
Cardiogenic oscillations appear when:
A continuous fresh gas flow is fed into the patient Y-piece.
●
Sidestream gas sampling is done at the Y-piece.
●
The patient is ventilated with a long expiration time or low respiration times, and
●
when there is a long zero flow at end-expiration for some other reason.
CO₂ measurement practicalities

Ventilation management

Normoventilation (adequate alveolar ventilation of a patient) can be maintained
by monitoring the end-tidal carbon dioxide and oxygen concentrations, and
adequacy of ventilation can be maintained by monitoring airway pressures, volumes
and spirometry loops. Alveolar minute ventilation is usually adjusted to achieve
normocapnia, where EtCO
This is called normoventilation as it is the normal situation in healthy people.
A low EtCO
NOTE
Increased EtCO
ineffective alveolar ventilation, which will lead to hypercapnia and respiratory acidosis.
Increased inspiratory CO
Exhausted CO
●
Malfunction of the breathing system valves.
●
Rebreathing when a rebreathing system without a CO
●
inadequate fresh gas flows.
NOTE
2094480-001
is in the range of 4.5% to 5.5% (34 mmHg to 41 mmHg).
2
concentration (EtCO < 4% / 30 mmHg) indicates hyperventilation.
2 2
A low EtCO
2
volume vs. circulation status (lung perfusion). This means
that in case of low blood pressure (e.g. shock), shunting, a
pulmonary embolism, or a leak, low EtCO
observed while using a "normal" TV/MV.
concentration (EtCO
2
(FiCO ) concentrations may also be caused by:
2 2
absorber.
2
During some surgical procedures, e.g. laparoscopy, CO
be used to inflate the abdomen which may result in rise of
PaCO due to the absorption of CO
2
vascular wound bed. This may lead to an increase in the
EtCO .
2
CARESCAPE ONE
value in itself is dependent on the ventilation
> 6.0% / 45 mmHg) indicates hypoventilation or
2
absorber is used with
2
2
CO₂
values may be
2
may
2
into the blood via the
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