What are the phases of capnography?
- Phase I (inspiratory baseline) reflects inspired gas, which is normally devoid of carbon dioxide.
- Phase II (expiratory upstroke) is the transition between VDana, which does not participate in gas exchange, and alveolar gas from the respiratory bronchioles and alveoli.
- Phase III is the alveolar plateau.
What is a normal end-tidal CO2 reading?
End-tidal CO2 (EtCO2) monitoring is a noninvasive technique which measures the partial pressure or maximal concentration of carbon dioxide (CO2) at the end of an exhaled breath, which is expressed as a percentage of CO2 or mmHg. The normal values are 5% to 6% CO2, which is equivalent to 35-45 mmHg.
What to do if end-tidal CO2 is high?
No change or a rising ETCO2 level indicates that respiratory effort is still failing to adequately eliminate CO2, and that more other interventions are needed. A patient receiving supplemental oxygen may need CPAP, and patients whose ETCO2 rises with CPAP may need assisted ventilation with a BVM.
What should end-tidal CO2 be kPa?
Current guidance recommends an end- tidal carbon dioxide (ETCO2) of 4.0–4.5 kPa (30.0– 33.8 mm Hg) to achieve a low- normal arterial partial pressure of CO2 (PaCO2), and reduce secondary brain injury.
What is ETCO2?
ETCO2 is the amount of carbon dioxide (CO2) in exhaled air, which assesses ventilation. So a high ETCO2 is a good sign of good ventilation, while low ETCO2 is bad sign that represents hypoventilation.
What does a high end tidal CO2 mean?
Why do we use ETCO2?
ETCO2 is an indispensable tool in assessing the severity of obstructive respiratory disease in the emergency department. ETCO2 is higher in patients with COPD exacerbation who are admitted to the hospital compared to those who are discharged from the emergency department (35).
What is the name of the second phase of capnography?
Phase II (expiratory upstroke) is the transition between VD ana, which does not participate in gas exchange, and alveolar gas from the respiratory bronchioles and alveoli. Phase III is the alveolar plateau. Traditionally, PCO 2 of the last alveolar gas sampled at the airway opening is called the PETCO 2.
When does Phase 1 start on a capnogram?
Phase 1 occurs as exhalation begins, which is shown as A to B on the capnogram. The first gas to appear at the sampling point is the last gas that was inhaled into the conducting airways.
What is the terminal upswing of a capnogram?
Occasionally, at the end of phase III, a terminal upswing, phase IV, may occur. Represents the CO 2 -free gas from the airways (anatomical and apparatus dead space). Consists of a rapid S-shaped upswing on the tracing (due to mixing of dead space gas with alveolar gas). Consists of an alveolar plateau representing CO 2 -rich gas from the alveoli.
Which is the first gas on the capnogram?
Phase 1 occurs as exhalation begins, which is shown as A to B on the capnogram. The first gas to appear at the sampling point is the last gas that was inhaled into the conducting airways. This gas has not been subjected to gas exchange and thus is essentially free of carbon dioxide and remains at the zero baseline.