Abstract:Regional ventilation distribution patterns during inspiration were associated with weaning outcomes, and they may be used to predict the success of extubation.
“…These findings coincided with those of the Taiwan group in studying prolonged mechanically ventilated (PMV) patients [189,190]. In the study with 30 PMV patients, intratidal ventilation distribution was correlated to weaning outcome, which indicated that EIT has the potential to predict the weaning outcome and lower the extubation failure rate [190]. In twenty mechanically ventilated patients after elective cardiac surgery, Karsten et al [191] found that the "best" PEEP value identified by individual maximum respiratory system compliance was lower than optimal PEEP levels determined by EIT.…”
Section: Applications In Perioperative Patientssupporting
confidence: 84%
“…The effect of trigger sensitivity could be revealed by EIT-based intratidal ventilation distribution. These findings coincided with those of the Taiwan group in studying prolonged mechanically ventilated (PMV) patients [189,190]. In the study with 30 PMV patients, intratidal ventilation distribution was correlated to weaning outcome, which indicated that EIT has the potential to predict the weaning outcome and lower the extubation failure rate [190].…”
Section: Applications In Perioperative Patientssupporting
Electrical Impedance Tomography (EIT) is under fast development, the present paper is a review of some procedures that are contributing to improve spatial resolution and material properties accuracy, admitivitty or impeditivity accuracy. A review of EIT medical applications is presented and they were classified into three broad categories: ARDS patients, obstructive lung diseases and perioperative patients. The use of absolute EIT image may enable the assessment of absolute lung volume, which may significantly improve the clinical acceptance of EIT. The Control Theory, the State Observers more specifically, have a developed theory that can be used for the design and operation of EIT devices. Electrode placement, current injection strategy and electrode electric potential measurements strategy should maximize the number of observable and controllable directions of the state vector space. A non-linear stochastic state observer, the Unscented Kalman Filter, is used directly for the reconstruction of absolute EIT images. Historically, difference images were explored first since they are more stable in the presence of modelling errors. Absolute images require more detailed models of contact impedance, stray capacitance and properly refined finite element mesh where the electric potential gradient is high. Parallelization of the forward *
“…These findings coincided with those of the Taiwan group in studying prolonged mechanically ventilated (PMV) patients [189,190]. In the study with 30 PMV patients, intratidal ventilation distribution was correlated to weaning outcome, which indicated that EIT has the potential to predict the weaning outcome and lower the extubation failure rate [190]. In twenty mechanically ventilated patients after elective cardiac surgery, Karsten et al [191] found that the "best" PEEP value identified by individual maximum respiratory system compliance was lower than optimal PEEP levels determined by EIT.…”
Section: Applications In Perioperative Patientssupporting
confidence: 84%
“…The effect of trigger sensitivity could be revealed by EIT-based intratidal ventilation distribution. These findings coincided with those of the Taiwan group in studying prolonged mechanically ventilated (PMV) patients [189,190]. In the study with 30 PMV patients, intratidal ventilation distribution was correlated to weaning outcome, which indicated that EIT has the potential to predict the weaning outcome and lower the extubation failure rate [190].…”
Section: Applications In Perioperative Patientssupporting
Electrical Impedance Tomography (EIT) is under fast development, the present paper is a review of some procedures that are contributing to improve spatial resolution and material properties accuracy, admitivitty or impeditivity accuracy. A review of EIT medical applications is presented and they were classified into three broad categories: ARDS patients, obstructive lung diseases and perioperative patients. The use of absolute EIT image may enable the assessment of absolute lung volume, which may significantly improve the clinical acceptance of EIT. The Control Theory, the State Observers more specifically, have a developed theory that can be used for the design and operation of EIT devices. Electrode placement, current injection strategy and electrode electric potential measurements strategy should maximize the number of observable and controllable directions of the state vector space. A non-linear stochastic state observer, the Unscented Kalman Filter, is used directly for the reconstruction of absolute EIT images. Historically, difference images were explored first since they are more stable in the presence of modelling errors. Absolute images require more detailed models of contact impedance, stray capacitance and properly refined finite element mesh where the electric potential gradient is high. Parallelization of the forward *
“…17 Mechanical ventilation contributes additionally to heterogeneous ventilation distribution. 18 Spontaneous breathing leads to ventilation redistribution toward dorsal regions, 19 which may be beneficial to reduce atelectasis introduced by anesthesia and mechanical ventilation. However, after extubation, especially with insufficient end-expiratory positive pressure support, lung volume may fall significantly.…”
BACKGROUND: The aim of this prospective randomized crossover study was to compare the short-term effects of high-flow nasal cannula (HFNC) therapy and a 45°head-up tilt to the shortterm effects of conventional oxygen (O 2) therapy in post-abdominal surgery patients. METHODS: A total of 18 subjects who were successfully weaned from ventilator support after abdominal surgery were included in the study. The subjects were randomly assigned to 2 groups: conventional O 2 was applied in group A for 15 min, and HFNC (60 L/min) was applied in group B for 15 min. A 15-min washout period with conventional O 2 was performed before the interventions were switched in both groups. Heart rate, blood pressure, breathing frequency, ratio of arterial partial pressure of oxygen to the fraction of inspired oxygen (P aO 2 /F IO 2), and subject-reported comfort scores were recorded. Changes in end-expiratory lung impedance (EELI) were calculated with electrical impedance tomography. RESULTS: Results are presented as the percent change in lung volume compared to baseline during volume-controlled continuous mandatory ventilation before extubation. HFNC improved EELI in both the ventral (conventional O 2 vs HFNC, ؊48.2% ؎ 41.0 vs ؊30.0% ؎ 40.3, P < .001) and the dorsal (conventional O 2 vs HFNC, ؊37.0% ؎ 75.9 vs ؊26.5% ؎ 68.4, P ؍ .02) regions of the lungs. Subjective subject-reported scores indicated that HFNC was more comfortable than conventional O 2 (conventional O 2 vs HFNC, 5.8 ؎ 1.5 vs 6.9 ؎ 1.9, P ؍ .02). No differences were found in the other examined parameters. A head-up tilt position with conventional O 2 improved EELI in the dorsal regions (55.9% ؎ 100.1, P < .001) but not in the ventral regions (؊37.9% ؎ 43.1%, P ؍ .38) of the lungs compared to HFNC or conventional O 2 alone. CONCLUSIONS: In post-abdominal surgery subjects who had been extubated, HFNC improved lung volume and patient comfort. A head-up tilt position introduced a heterogeneous increase in EELI in the dorsal regions of the lungs. HFNC therapy may be beneficial in this patient group.
“…External continuous positive airway pressure or T-piece methods were used for spontaneous breathing trial. Strategy of spontaneous breathing trial in our center was described in previous studies [25, 26]. After extubation, patients were supported by noninvasive bilevel positive airway pressure mode.Fig.…”
BackgroundThe study objective was to compare titration of positive end-expiratory pressure (PEEP) with electrical impedance tomography (EIT) and with ventilator-embedded pressure–volume loop in severe acute respiratory distress syndrome (ARDS).MethodsWe have designed a prospective study with historical control group. Twenty-four severe ARDS patients (arterial oxygen partial pressure to fractional inspired oxygen ratio, PaO2/FiO2 < 100 mmHg) were included in the EIT group and examined prospectively. Data from another 31 severe ARDS patients were evaluated retrospectively (control group). All patients were receiving medical care under identical general support guidelines and protective mechanical ventilation. The PEEP level selected in the EIT group was the intercept point of cumulated collapse and overdistension percentages curves. In the control group, optimal PEEP was selected 2 cmH2O above the lower inflection point on the static pressure–volume curve.ResultsPatients in the EIT group were younger (P < 0.05), and their mean plateau pressure was 1.5 cmH2O higher (P < 0.01). No differences in other baseline parameters such as APACHE II score, PaO2/FiO2, initial PEEP, driving pressure, tidal volume, and respiratory system compliance were found. Two hours after the first PEEP titration, significantly higher PEEP, compliance, and lower driving pressure were found in the EIT group (P < 0.01). Hospital survival rates were 66.7% (16 of 24 patients) in the EIT group and 48.4% (15 of 31) in the control group. Identical rates were found regarding the weaning success rate: 66.7% in the EIT group and 48.4% in the control group.ConclusionIn severe ARDS patients, it was feasible and safe to guide PEEP titration with EIT at the bedside. As compared with pressure–volume curve, the EIT-guided PEEP titration may be associated with improved oxygenation, compliance, driving pressure, and weaning success rate. The findings encourage further randomized control study with a larger sample size and potentially less bias in the baseline data.Trial Registration NCT03112512Electronic supplementary materialThe online version of this article (10.1186/s13613-019-0484-0) contains supplementary material, which is available to authorized users.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
