Hypercapnia
Conditions
Keywords
spectroscopy, near-infrared, Infant, Anesthesia, general
Brief summary
The purpose of this study is to show that a permissive hypercapnia during mechanical ventilation in children under general anaesthesia will improve cerebral perfusion.
Detailed description
Mechanical ventilation interferes with cerebral perfusion via the changes in intrathoracic pressure and/or as a consequence of hypocapnia. This latter occurs frequently following traditional ventilation strategies with relatively high tidal volume and respiratory rate. New trends in anesthesia intend to promote protective lung ventilation by keeping a normocapnic or even mildly hypercapnic state. However, cerebral vascular vasotonicity is carbon dioxide (CO2)-dependent with hypocapnia potentially leading to vasoconstriction and subsequent decrease in cerebral blood flow. Changes in cerebral vasoreactivity can be assessed by the near infrared spectroscopy (NIRS) device. This monitoring evaluates the changes in various parameters (deoxygenated hemoglobin, oxygenated hemoglobin, the tissue oxygenation index (TOI) and the tissue hemoglobin index (THI)) that act as surrogate for cerebral vasoconstriction. We, therefore designed this prospective observational comparative effectiveness study in order to characterize the potential beneficial effect of permissive hypercapnia on cerebral perfusion in infants.
Interventions
OTHERNormocapnia
Normoventilation in order to have an end-tidal carbon dioxide (ETCO2) of 5.5 kiloPascal (kPa)
OTHERMild Hypercapnia
Decrease in minute ventilation in order to increase ETCO2 to 6.5 kPa
Sponsors
Walid HABRE
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
SUPPORTIVE_CARE
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
1 Days to 1 Years
Healthy volunteers
No
Inclusion criteria
* term neonates during their infancy * for elective surgery requiring general anesthesia and endotracheal intubation
Exclusion criteria
* all infants with cardiac anomalies, chronic pulmonary disease (bronchopulmonary dysplasia, cystic fibrosis, asthma), pulmonary hypertension or cranial hypertension will be excluded * all infants where no access to the forehead is possible as a consequence of the operating field
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| Assessment of the changes in TOI and THI as measured by NIRS under normocapnia and permissive hypercapnia | At steady state (2-3 minutes) after achieving each level of ETCO2 and every 2 minutes up to 6 minutes for each level |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Blood gas analysis | 5 or 20 minutes after reaching the steady state with ETCO2 | Assessment changes in oxygen partial pressure (PaO2), carbon dioxide partial pressure (PaCO2) and potential of hydrogen (pH) under one level of ETCO2 |
| Blood Pressure | At steady state (2-3 minutes) after achieving each level of ETCO2 and every 2 minutes up to 6 minutes for each level | Non invasive monitoring of blood pressure |
| Heart rate | At steady state (2-3 minutes) after achieving each level of ETCO2 and every 2 minutes up to 6 minutes for each level | Non invasive recording of heart rate |
| Body temperature | At steady state (2-3 minutes) after achieving each level of ETCO2 and every 2 minutes up to 6 minutes for each level | Naso-pharyngeal temperature probe |
Countries
Switzerland
Outcome results
None listed