Abstract:
:Electrical impedance tomography (EIT) has the potential to become a new tool for bedside monitoring of regional lung ventilation. The aim of our study was to assess the reproducibility of regional lung ventilation distribution determined by EIT during mechanical ventilation under identical ventilator settings. The experiments were performed on 10 anaesthetized supine pigs ventilated in a volume-controlled mode. EIT measurements were performed with the Goe-MF II device (Viasys Healthcare, Höchberg, Germany) during repeated changes in positive end-expiratory pressure (PEEP) from 0 to 10 cm H2O. Regional lung ventilation was determined in the right and left hemithorax as well as in 64 regions of interest evenly distributed over each chest side in the ventrodorsal direction. Ventilation distributions in both lungs were visualized as ventrodorsal ventilation profiles and shifts in ventilation distribution quantified in terms of centres of ventilation in relation to the chest diameter. The proportion of the right lung on total ventilation in the chest cross-section was 0.54+/-0.04 and remained unaffected by repetitive PEEP changes. Initial PEEP increase resulted in a redistribution of ventilation towards dorsal lung regions with a shift of the centre of ventilation from 45+/-3% to 49+/-3% of the chest diameter in the right and from 47+/-2% to 50+/-2% in the left hemithorax. Excellent reproducibility of the results in the individual regions of interest with almost identical patterns of ventilation distribution was found during repeated PEEP changes.
journal_name
Physiol Measjournal_title
Physiological measurementauthors
Frerichs I,Schmitz G,Pulletz S,Schädler D,Zick G,Scholz J,Weiler Ndoi
10.1088/0967-3334/28/7/S19subject
Has Abstractpub_date
2007-07-01 00:00:00pages
S261-7issue
7eissn
0967-3334issn
1361-6579pii
S0967-3334(07)36585-4journal_volume
28pub_type
杂志文章abstract:OBJECTIVE:The ratio of the partial pressure of arterial oxygen to fraction of inspired oxygen is a key component of the sequential organ failure assessment score that operationally defines sepsis. But, it is calculated infrequently due to the need for the acquisition of an arterial blood gas. So, we sought to find an o...
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