Background: The application of positive end-expiratory pressure (PEEP) may reduce dynamic strain during mechanical ventilation. Although numerous approaches for PEEP titration have been proposed, there is no accepted strategy for titrating optimal PEEP. By analyzing intratidal compliance profiles, PEEP may be individually titrated for patients.Methods: After obtaining informed consent, 60 consecutive patients undergoing general anesthesia were randomly allocated to mechanical ventilation with PEEP 5 cmH 2 O (control group) or PEEP individually titrated, guided by an analysis of the intratidal compliance profile (intervention group). The primary endpoint was the frequency of each nonlinear intratidal compliance (C RS ) profile of the respiratory system (horizontal, increasing, decreasing, and mixed). The secondary endpoints measured were respiratory mechanics, hemodynamic variables, and regional ventilation, which was assessed via electrical impedance tomography.Results: The frequencies of the C RS profiles were comparable between the groups. Besides PEEP [control: 5.0 (0.0), intervention: 5.8 (1.1) cmH 2 O, p < 0.001], the respiratory and hemodynamic variables were comparable between the two groups. The compliance profile analysis showed no significant differences between the two groups. The loss of ventral and dorsal regional ventilation was higher in the control [ventral: 41.0 (16.3)%; dorsal: 25.9 (13.8)%] than in the intervention group [ventral: 29.3 (17.6)%; dorsal: 16.4 (12.7)%; p (ventral) = 0.039, p (dorsal) = 0.028]. Conclusions: Unfavorable compliance profiles indicating tidal derecruitment were found less often than in earlier studies. Individualized PEEP titration resulted in slightly higher PEEP. A slight global increase in aeration associated with this was indicated by regional gain and loss analysis. Differences in dorsal to ventral ventilation distribution were not found.Trial registration: This clinical trial was registered at the German Register for Clinical Trials (DRKS00008924) on August 10, 2015.

Background Application of positive end-expiratory pressure (PEEP) improves lung aeration and reduces mechanical stress during mechanical ventilation. Although numerous approaches for PEEP titration have been proposed, there is no accepted strategy to titrate optimal PEEP. By analyzing the intratidal compliance profiles, PEEP may be titrated patient-individually. Methods After obtaining informed consent, we measured respiratory system mechanics, regional ventilation in 60 consecutive patients undergoing elective surgery, randomly allocated to the control group (PEEP = 5 cmH 2 O) or the intervention group receiving individually titrated PEEP, guided by intratidal compliance profile analysis. Primary endpoint was the frequencies of nonlinear intratidal compliance (C RS ) profiles of the respiratory system (horizontal, increasing, decreasing and mixed). We further investigated respiratory and hemodynamic variables and regional ventilation. Results Frequencies of C RS profiles were comparable between the groups. Besides PEEP [control: 5.0 (0.0), intervention: 5.8 (1.1) cmH 2 O, p<0.001] respiratory and hemodynamic variables were comparable between the two groups. The compliance profile analysis showed no significant differences between the two groups. The loss of ventral and dorsal regional ventilation was higher in the control [ventral: 41.0 (16.3) %, dorsal: 25.9 (13.8) %] than in the intervention group [ventral: 29.3 (17.6) %, dorsal: 16.4 (12.7) %, p (ventral) = 0.039, p (dorsal) = 0.028]. Conclusions Individualized PEEP titration according to bedside compliance profile analysis improves regional ventilation in terms of global aeration gain without affecting respiratory and hemodynamic variables negatively and might be a promising approach to patient-individual ventilation settings. However, differences in dorsal to ventral ventilation distribution were not found. Unfavorable compliance profiles indicating tidal derecruitment were found less often than in earlier studies.

Background Application of positive end-expiratory pressure (PEEP) improves lung aeration and reduces mechanical stress during mechanical ventilation. Although numerous approaches for PEEP titration have been proposed, there is no accepted strategy to titrate optimal PEEP. By analyzing the intratidal compliance profiles, PEEP may be titrated patient-individually. Methods After obtaining informed consent, we measured respiratory system mechanics and regional ventilation in 60 consecutive patients undergoing elective surgery, randomly allocated to the control group (PEEP = 5 cmH 2 O) or the intervention group receiving individually titrated PEEP, guided by intratidal compliance profile analysis. Primary endpoint was the nonlinear intratidal compliance. We further investigated respiratory and hemodynamic variables, regional ventilation and compliance profiles. Results Compliance was comparable between control [63.2 (14.0) mL·cmH 2 O -1 ] and intervention group [67.8 (15.9) mL·cmH 2 O -1 , p = 0.271]. Besides PEEP [control: 5.0 (0.0), intervention: 5.8 (1.1) cmH 2 O] respiratory and hemodynamic variables were comparable between the two groups. The compliance profile analysis showed no significant differences between the two groups. Relative thoracic electrical impedance was better maintained in the intervention group (89.3 (19.4) %) than in the control group (78.3 (23.6) %, p < 0.001). No significant differences in dorsal to ventral ventilation distribution was found between the two groups. Conclusions Individualized PEEP titration according to bedside compliance profile analysis improves regional ventilation without affecting respiratory and hemodynamic variables negatively and may be a promising approach to patient-individual ventilation setting.

Background The application of positive end-expiratory pressure (PEEP) may reduce dynamic strain during mechanical ventilation. Although numerous approaches for PEEP titration have been proposed, there is no accepted strategy for titrating optimal PEEP. By analyzing intratidal compliance profiles, PEEP may be individually titrated for patients. Methods After obtaining informed consent, 60 consecutive patients undergoing general anesthesia were randomly allocated to mechanical ventilation with PEEP 5 cmH2O (control group) or PEEP individually titrated, guided by an analysis of the intratidal compliance profile (intervention group). The primary endpoint was the frequency of each nonlinear intratidal compliance (CRS) profile of the respiratory system (horizontal, increasing, decreasing, and mixed). The secondary endpoints measured were respiratory mechanics, hemodynamic variables, and regional ventilation, which was assessed via electrical impedance tomography. Results The frequencies of the CRS profiles were comparable between the groups. Besides PEEP [control: 5.0 (0.0), intervention: 5.8 (1.1) cmH2O, p < 0.001], the respiratory and hemodynamic variables were comparable between the two groups. The compliance profile analysis showed no significant differences between the two groups. The loss of ventral and dorsal regional ventilation was higher in the control [ventral: 41.0 (16.3)%; dorsal: 25.9 (13.8)%] than in the intervention group [ventral: 29.3 (17.6)%; dorsal: 16.4 (12.7)%; p (ventral) = 0.039, p (dorsal) = 0.028]. Conclusions Unfavorable compliance profiles indicating tidal derecruitment were found less often than in earlier studies. Individualized PEEP titration resulted in slightly higher PEEP. A slight global increase in aeration associated with this was indicated by regional gain and loss analysis. Differences in dorsal to ventral ventilation distribution were not found.

Background The application of positive end-expiratory pressure (PEEP) may reduce dynamic strain during mechanical ventilation. Although numerous approaches for PEEP titration have been proposed, there is no accepted strategy for titrating optimal PEEP. By analyzing intratidal compliance profiles, PEEP may be individually titrated for patients. Methods After obtaining informed consent, 60 consecutive patients undergoing general anesthesia were randomly allocated to mechanical ventilation with PEEP 5 cmH 2 O (control group) or PEEP individually titrated, guided by an analysis of the intratidal compliance profile (intervention group). The primary endpoint was the frequency of each nonlinear intratidal compliance (C RS ) profile of the respiratory system (horizontal, increasing, decreasing, and mixed). The secondary endpoints measured were respiratory mechanics, hemodynamic variables, and regional ventilation, which was assessed via electrical impedance tomography. Results The frequencies of the C RS profiles were comparable between the groups. Besides PEEP [control: 5.0 (0.0), intervention: 5.8 (1.1) cmH 2 O, p < 0.001], the respiratory and hemodynamic variables were comparable between the two groups. The compliance profile analysis showed no significant differences between the two groups. The loss of ventral and dorsal regional ventilation was higher in the control [ventral: 41.0 (16.3)%; dorsal: 25.9 (13.8)%] than in the intervention group [ventral: 29.3 (17.6)%; dorsal: 16.4 (12.7)%; p (ventral) = 0.039, p (dorsal) = 0.028]. Conclusions Unfavorable compliance profiles indicating tidal derecruitment were found less often than in earlier studies. Individualized PEEP titration resulted in slightly higher PEEP. A slight global increase in aeration associated with this was indicated by regional gain and loss analysis. Differences in dorsal to ventral ventilation distribution were not found.