uu.seUppsala University Publications
Change search
Refine search result
1 - 23 of 23
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Rows per page
  • 5
  • 10
  • 20
  • 50
  • 100
  • 250
Sort
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
Select
The maximal number of hits you can export is 250. When you want to export more records please use the Create feeds function.
  • 1.
    Ahlström, J. Zebialowicz
    et al.
    Karolinska Inst, Div Neurogeriatr, Dept Neurobiol Care Sci & Soc, Huddinge, Sweden.
    Massaro, F.
    Swedish Univ Agr Sci, Dept Anat Physiol & Biochem, Uppsala, Sweden.
    Mikolka, P.
    Karolinska Inst, Div Neurogeriatr, Dept Neurobiol Care Sci & Soc, Huddinge, Sweden;Comenius Univ, Jessenius Fac Med Martin, Biomed Ctr Martin, Martin, TN USA;Comenius Univ, Jessenius Fac Med Martin, Dept Physiol, Martin, TN USA.
    Feinstein, R.
    Swedish Natl Vet Inst, Dept Pathol, Uppsala, Sweden.
    Perchiazzi, Gaetano
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Hedenstierna laboratory. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Anaesthesiology and Intensive Care. Uppsala Univ, Dept Surg Sci, Hedenstierna Lab, Uppsala, Sweden.
    Basabe-Burgos, O.
    Karolinska Inst, Div Neurogeriatr, Dept Neurobiol Care Sci & Soc, Huddinge, Sweden.
    Curstedt, T.
    Karolinska Inst, Karolinska Univ Hosp, Dept Mol Med & Surg, Stockholm, Sweden.
    Larsson, Anders
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Anaesthesiology and Intensive Care. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Hedenstierna laboratory.
    Johansson, J.
    Karolinska Inst, Div Neurogeriatr, Dept Neurobiol Care Sci & Soc, Huddinge, Sweden.
    Rising, A.
    Karolinska Inst, Div Neurogeriatr, Dept Neurobiol Care Sci & Soc, Huddinge, Sweden;Swedish Univ Agr Sci, Dept Anat Physiol & Biochem, Uppsala, Sweden.
    Synthetic surfactant with a recombinant surfactant protein C analogue improves lung function and attenuates inflammation in a model of acute respiratory distress syndrome in adult rabbits2019In: Respiratory Research, ISSN 1465-9921, E-ISSN 1465-993X, Vol. 20, article id 245Article in journal (Refereed)
    Abstract [en]

    AimIn acute respiratory distress syndrome (ARDS) damaged alveolar epithelium, leakage of plasma proteins into the alveolar space and inactivation of pulmonary surfactant lead to respiratory dysfunction. Lung function could potentially be restored with exogenous surfactant therapy, but clinical trials have so far been disappointing. These negative results may be explained by inactivation and/or too low doses of the administered surfactant. Surfactant based on a recombinant surfactant protein C analogue (rSP-C33Leu) is easy to produce and in this study we compared its effects on lung function and inflammation with a commercial surfactant preparation in an adult rabbit model of ARDS.MethodsARDS was induced in adult New Zealand rabbits by mild lung-lavages followed by injurious ventilation (V-T 20m/kg body weight) until P/F ratio<26.7kPa. The animals were treated with two intratracheal boluses of 2.5mL/kg of 2% rSP-C33Leu in DPPC/egg PC/POPG, 50:40:10 or poractant alfa (Curosurf (R)), both surfactants containing 80mg phospholipids/mL, or air as control. The animals were subsequently ventilated (V-T 8-9m/kg body weight) for an additional 3h and lung function parameters were recorded. Histological appearance of the lungs, degree of lung oedema and levels of the cytokines TNF alpha IL-6 and IL-8 in lung homogenates were evaluated.ResultsBoth surfactant preparations improved lung function vs. the control group and also reduced inflammation scores, production of pro-inflammatory cytokines, and formation of lung oedema to similar degrees. Poractant alfa improved compliance at 1h, P/F ratio and PaO2 at 1.5h compared to rSP-C33Leu surfactant.ConclusionThis study indicates that treatment of experimental ARDS with synthetic lung surfactant based on rSP-C33Leu improves lung function and attenuates inflammation.

  • 2.
    Barrueta Tenhunen, Annelie
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Hedenstierna laboratory.
    Massaro, Fabrizia
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Hedenstierna laboratory. Anthea Hosp, GVM Care & Res, Cardiac Anesthesia & Intens Care, Bari, Italy.
    Hansson, Hans Arne
    Univ Gothenburg, Inst Biomed, Gothenburg, Sweden.
    Feinstein, Ricardo
    Natl Vet Inst, Dept Pathol & Wildlife Dis, Uppsala, Sweden.
    Larsson, Anders
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Clinical Chemistry.
    Larsson, Anders
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Hedenstierna laboratory.
    Perchiazzi, Gaetano
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Hedenstierna laboratory.
    Does the antisecretory peptide AF-16 reduce lung oedema in experimental ARDS?In: Upsala Journal of Medical Sciences, ISSN 0300-9734, E-ISSN 2000-1967Article in journal (Refereed)
    Abstract [en]

    Background: Acute respiratory distress syndrome (ARDS) is an acute inflammatory condition with pulmonary capillary leakage and lung oedema formation. There is currently no pharmacologic treatment for the condition. The antisecretory peptide AF-16 reduces oedema in experimental traumatic brain injury. In this study, we tested AF-16 in an experimental porcine model of ARDS.

    Methods: Under surgical anaesthesia 12 piglets were subjected to lung lavage followed by 2 hours of injurious ventilation. Every hour for 4 hours, measurements of extravascular lung water (EVLW), mechanics of the respiratory system, and hemodynamics were obtained.

    Results: There was a statistically significant (p = 0.006, two-way ANOVA) reduction of EVLW in the AF-16 group compared with controls. However, this was not mirrored in any improvement in the wet-to-dry ratio of lung tissue samples, histology, inflammatory markers, lung mechanics, or gas exchange.

    Conclusions: This pilot study suggests that AF-16 might improve oedema resolution as indicated by a reduction in EVLW in experimental ARDS.

  • 3.
    Borges, João Batista
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Anaesthesiology and Intensive Care. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Hedenstierna laboratory. Univ Sao Paulo, Fac Med, Hosp Clin, Pulm Div,Heart Inst Incor, BR-05508 Sao Paulo, Brazil..
    Porra, L.
    Univ Helsinki, Dept Phys, Helsinki, Finland.;Univ Helsinki, Cent Hosp, Helsinki, Finland..
    Pellegrini, M.
    Univ Bari, Dept Emergency & Organ Transplant, I-70121 Bari, Italy..
    Tannoia, A.
    Univ Bari, Dept Emergency & Organ Transplant, I-70121 Bari, Italy..
    Derosa, S.
    Univ Bari, Dept Emergency & Organ Transplant, I-70121 Bari, Italy..
    Larsson, Anders
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Anaesthesiology and Intensive Care. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Hedenstierna laboratory.
    Bayat, S.
    Univ Picardie Jules Verne, CHU Amiens, INSERM, UMR1105, Amiens, France.;Univ Picardie Jules Verne, CHU Amiens, Pediat Lung Funct Lab, Amiens, France..
    Perchiazzi, Gaetano
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Anaesthesiology and Intensive Care. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Hedenstierna laboratory. Univ Bari, Dept Emergency & Organ Transplant, I-70121 Bari, Italy..
    Hedenstierna, G.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Clinical Physiology. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Hedenstierna laboratory.
    Zero expiratory pressure and low oxygen concentration promote heterogeneity of regional ventilation and lung densities2016In: Acta Anaesthesiologica Scandinavica, ISSN 0001-5172, E-ISSN 1399-6576, Vol. 60, no 7, p. 958-968Article in journal (Refereed)
    Abstract [en]

    BackgroundIt is not well known what is the main mechanism causing lung heterogeneity in healthy lungs under mechanical ventilation. We aimed to investigate the mechanisms causing heterogeneity of regional ventilation and parenchymal densities in healthy lungs under anesthesia and mechanical ventilation. MethodsIn a small animal model, synchrotron imaging was used to measure lung aeration and regional-specific ventilation (sV.). Heterogeneity of ventilation was calculated as the coefficient of variation in sV. (CVsV.). The coefficient of variation in lung densities (CVD) was calculated for all lung tissue, and within hyperinflated, normally and poorly aerated areas. Three conditions were studied: zero end-expiratory pressure (ZEEP) and FIO2 0.21; ZEEP and FIO2 1.0; PEEP 12 cmH(2)O and F(I)O(2)1.0 (Open Lung-PEEP = OLP). ResultsThe mean tissue density at OLP was lower than ZEEP-1.0 and ZEEP-0.21. There were larger subregions with low sV. and poor aeration at ZEEP-0.21 than at OLP: 12.9 9.0 vs. 0.6 +/- 0.4% in the non-dependent level, and 17.5 +/- 8.2 vs. 0.4 +/- 0.1% in the dependent one (P = 0.041). The CVsV. of the total imaged lung at PEEP 12 cmH(2)O was significantly lower than on ZEEP, regardless of FIO2, indicating more heterogeneity of ventilation during ZEEP (0.23 +/- 0.03 vs. 0.54 +/- 0.37, P = 0.049). CVD changed over the different mechanical ventilation settings (P = 0.011); predominantly, CVD increased during ZEEP. The spatial distribution of the CVD calculated for the poorly aerated density category changed with the mechanical ventilation settings, increasing in the dependent level during ZEEP. ConclusionZEEP together with low FIO2 promoted heterogeneity of ventilation and lung tissue densities, fostering a greater amount of airway closure and ventilation inhomogeneities in poorly aerated regions.

  • 4.
    Broche, Ludovic
    et al.
    European Synchrotron Radiat Facil, Biomed Beamline ID17, Grenoble, France.;Univ Picardie Jules Verne, INSERM, Dept Pediat Pulmonol, U1105, Amiens, France.;Amiens Univ Hosp, Amiens, France..
    Perchiazzi, Gaetano
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Hedenstierna laboratory. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Anaesthesiology and Intensive Care.
    Porra, Liisa
    Univ Helsinki, Dept Phys, Helsinki, Finland.;Univ Helsinki, Cent Hosp, Helsinki, Finland..
    Tannoia, Angela
    Univ Bari, Dept Emergency & Organ Transplant, Bari, Italy..
    Pellegrini, Mariangela
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Hedenstierna laboratory. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Anaesthesiology and Intensive Care.
    Derosa, Savino
    Univ Bari, Dept Emergency & Organ Transplant, Bari, Italy..
    Sindaco, Alessandra
    Univ Bari, Dept Emergency & Organ Transplant, Bari, Italy..
    Borges, João Batista
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Anaesthesiology and Intensive Care. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Hedenstierna laboratory.
    Degrugilliers, Loic
    Univ Picardie Jules Verne, INSERM, Dept Pediat Pulmonol, U1105, Amiens, France.;Amiens Univ Hosp, Amiens, France..
    Larsson, Anders
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Anaesthesiology and Intensive Care. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Hedenstierna laboratory.
    Hedenstierna, Göran
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Clinical Physiology. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Hedenstierna laboratory.
    Wexler, Anthony S.
    Univ Calif Davis, Dept Mech Engn, Davis, CA 95616 USA.;Univ Calif Davis, Environm Qual Lab, Davis, CA 95616 USA..
    Bravin, Alberto
    European Synchrotron Radiat Facil, Biomed Beamline ID17, Grenoble, France..
    Verbanck, Sylvia
    Univ Hosp UZ Brussel, Div Resp, Brussels, Belgium..
    Smith, Bradford J.
    Univ Vermont, Dept Med, Burlington, VT USA. European Synchrotron Radiat Facil, Grenoble, France..
    Bates, Jason H. T.
    Univ Vermont, Dept Med, Burlington, VT USA. European Synchrotron Radiat Facil, Grenoble, France..
    Bayat, Sam
    Univ Picardie Jules Verne, INSERM, Dept Pediat Pulmonol, U1105, Amiens, France.;Amiens Univ Hosp, Amiens, France..
    Dynamic Mechanical Interactions Between Neighboring Airspaces Determine Cyclic Opening and Closure in Injured Lung2017In: Critical Care Medicine, ISSN 0090-3493, E-ISSN 1530-0293, Vol. 45, no 4, p. 687-694Article in journal (Refereed)
    Abstract [en]

    Objectives: Positive pressure ventilation exposes the lung to mechanical stresses that can exacerbate injury. The exact mechanism of this pathologic process remains elusive. The goal of this study was to describe recruitment/derecruitment at acinar length scales over short-time frames and test the hypothesis that mechanical interdependence between neighboring lung units determines the spatial and temporal distributions of recruitment/derecruitment, using a computational model. Design: Experimental animal study. Setting: International synchrotron radiation laboratory. Subjects: Four anesthetized rabbits, ventilated in pressure controlled mode. Interventions: The lung was consecutively imaged at - 1.5-minute intervals using phase-contrast synchrotron imaging, at positive end expiratory pressures of 12, 9, 6, 3, and 0 cm H2O before and after lavage and mechanical ventilation induced injury. The extent and spatial distribution of recruitment/derecruitment was analyzed by subtracting subsequent images. In a realistic lung structure, we implemented a mechanistic model in which each unit has individual pressures and speeds of opening and closing. Derecruited and recruited lung fractions (F-derecruaed, F-recruited) were computed based on the comparison of the aerated volumes at successive time points. Measurements and Main Results: Alternative recruitment/derecruitment occurred in neighboring alveoli over short-time scales in all tested positive end-expiratory pressure levels and despite stable pressure controlled mode. The computational model reproduced this behavior only when parenchymal interdependence between neighboring acini was accounted for. Simulations closely mimicked the experimental magnitude of F-derecruited and F-recruited when mechanical interdependence was included, while its exclusion gave F-recruited values of zero at positive end -expiratory pressure greater than or equal to 3 cm H2O. Conclusions: These findings give further insight into the microscopic behavior of the injured lung and provide a means of testing protective-ventilation strategies to prevent recruitment/derecruitment and subsequent lung damage.

  • 5.
    Broche, Ludovic
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Hedenstierna laboratory. European Synchrotron Radiat Facil, Biomed Beamline ID17, Grenoble, France.
    Pisa, Pauline
    Univ Picardie Jules Verne, Fac Med, Amiens, France.
    Porra, Liisa
    Univ Helsinki, Dept Phys, Helsinki, Finland;Univ Helsinki, Cent Hosp, Med Imaging Ctr, Helsinki, Finland.
    Degrugilliers, Loic
    Amiens Univ Hosp, Dept Pediat Intens Care, Amiens, France.
    Bravin, Alberto
    European Synchrotron Radiat Facil, Biomed Beamline ID17, Grenoble, France.
    Pellegrini, Mariangela
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Hedenstierna laboratory.
    Batista Borges, João
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Hedenstierna laboratory.
    Perchiazzi, Gaetano
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Hedenstierna laboratory.
    Larsson, Anders
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Hedenstierna laboratory.
    Hedenstierna, Göran
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Hedenstierna laboratory.
    Bayat, Sam
    Univ Grenoble Alpes, Grenoble, France;INSERM, UA7, STROBE Lab, Grenoble, France;Grenoble Univ Hosp, Dept Pulmonol & Physiol, Grenoble, France.
    Individual Airway Closure Characterized In Vivo by Phase-Contrast CT Imaging in Injured Rabbit Lung2019In: Critical Care Medicine, ISSN 0090-3493, E-ISSN 1530-0293, Vol. 47, no 9, p. E774-E781Article in journal (Refereed)
    Abstract [en]

    Objectives: Airway closure is involved in adverse effects of mechanical ventilation under both general anesthesia and in acute respiratory distress syndrome patients. However, direct evidence and characterization of individual airway closure is lacking. Here, we studied the same individual peripheral airways in intact lungs of anesthetized and mechanically ventilated rabbits, at baseline and following lung injury, using high-resolution synchrotron phase-contrast CT.

    Design: Laboratory animal investigation.

    Setting: European synchrotron radiation facility.

    Subjects: Six New-Zealand White rabbits.

    Interventions: The animals were anesthetized, paralyzed, and mechanically ventilated in pressure-controlled mode (tidal volume, 6 mL/kg; respiratory rate, 40; Fio(2), 0.6; inspiratory:expiratory, 1:2; and positive end-expiratory pressure, 3 cm H2O) at baseline. Imaging was performed with a 47.5 x 47.5 x 47.5 mu m voxel size, at positive end-expiratory pressure 12, 9, 6, 3, and 0 cm H2O. The imaging sequence was repeated after lung injury induced by whole-lung lavage and injurious ventilation in four rabbits. Cross-sections of the same individual airways were measured.

    Measurements and Main Results: The airways were measured at baseline (n = 48; radius, 1.7 to 0.21 mm) and after injury (n = 32). Closure was observed at 0 cm H2O in three of 48 airways (6.3%; radius, 0.350.08 mm at positive end-expiratory pressure 12) at baseline and five of 32 (15.6%; radius, 0.28 +/- 0.09 mm) airways after injury. Cross-section was significantly reduced at 3 and 0 cm H2O, after injury, with a significant relation between the relative change in cross-section and airway radius at 12 cm H2O in injured, but not in normal lung (R = 0.60; p < 0.001).

    Conclusions: Airway collapsibility increases in the injured lung with a significant dependence on airway caliber. We identify "compliant collapse" as the main mechanism of airway closure in initially patent airways, which can occur at more than one site in individual airways.

  • 6.
    Cereda, Maurizio
    et al.
    Univ Penn, Dept Anesthesiol & Crit Care, Philadelphia, PA 19104 USA;Univ Penn, Dept Radiol, Philadelphia, PA 19104 USA.
    Xin, Yi
    Univ Penn, Dept Anesthesiol & Crit Care, Philadelphia, PA 19104 USA;Univ Penn, Dept Radiol, Philadelphia, PA 19104 USA.
    Goffi, Alberto
    Univ Toronto, Interdept Div Crit Care Med, Toronto, ON, Canada;Univ Toronto, Dept Med, Toronto, ON, Canada.
    Herrmann, Jacob
    Kaczka, David W.
    Univ Iowa, Dept Anesthesia & Biomed Engn, Iowa City, IA USA;Univ Iowa, Dept Anesthesia Radiol & Biomed Engn, Iowa City, IA USA.
    Kavanagh, Brian P.
    Univ Toronto, Hosp Sick Children, Toronto, ON, Canada.
    Perchiazzi, Gaetano
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Hedenstierna laboratory.
    Yoshida, Takeshi
    Univ Toronto, Hosp Sick Children, Toronto, ON, Canada.
    Rizi, Rahim R.
    Univ Penn, Dept Anesthesiol & Crit Care, Philadelphia, PA 19104 USA;Univ Penn, Dept Radiol, Philadelphia, PA 19104 USA.
    Imaging the Injured Lung: Mechanisms of Action and Clinical Use2019In: Anesthesiology, ISSN 0003-3022, E-ISSN 1528-1175, Vol. 131, no 3, p. 716-749Article, review/survey (Refereed)
    Abstract [en]

    Acute respiratory distress syndrome (ARDS) consists of acute hypoxemic respiratory failure characterized by massive and heterogeneously distributed loss of lung aeration caused by diffuse inflammation and edema present in interstitial and alveolar spaces. It is defined by consensus criteria, which include diffuse infiltrates on chest imaging-either plain radiography or computed tomography. This review will summarize how imaging sciences can inform modern respiratory management of ARDS and continue to increase the understanding of the acutely injured lung. This review also describes newer imaging methodologies that are likely to inform future clinical decision-making and potentially improve outcome. For each imaging modality, this review systematically describes the underlying principles, technology involved, measurements obtained, insights gained by the technique, emerging approaches, limitations, and future developments. Finally, integrated approaches are considered whereby multimodal imaging may impact management of ARDS.

  • 7.
    Gudmundsson, M
    et al.
    Department of Anaesthesiology and Intensive Care Medicine, Institute of Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.
    Perchiazzi, G
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Clinical Physiology. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Hedenstierna laboratory. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Anaesthesiology and Intensive Care.
    Pellegrini, Mariangela
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Hedenstierna laboratory. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Anaesthesiology and Intensive Care.
    Vena, A
    Department of Emergency and Organ Transplant, Bari University, Bari, Italy.
    Hedenstierna, Göran
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Clinical Physiology. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Hedenstierna laboratory.
    Rylander, Christian
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Hedenstierna laboratory. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences. Department of Anaesthesiology and Intensive Care Medicine, Institute of Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.
    Atelectasis is inversely proportional to transpulmonary pressure during weaning from ventilator support in a large animal model2018In: Acta Anaesthesiologica Scandinavica, ISSN 0001-5172, E-ISSN 1399-6576, Vol. 62, no 1, p. 94-104Article in journal (Refereed)
    Abstract [en]

    Background

    In mechanically ventilated, lung injured, patients without spontaneous breathing effort, atelectasis with shunt and desaturation may appear suddenly when ventilator pressures are decreased. It is not known how such a formation of atelectasis is related to transpulmonary pressure (PL) during weaning from mechanical ventilation when the spontaneous breathing effort is increased. If the relation between PL and atelectasis were known, monitoring of PL might help to avoid formation of atelectasis and cyclic collapse during weaning. The main purpose of this study was to determine the relation between PL and atelectasis in an experimental model representing weaning from mechanical ventilation.

    Methods

    Dynamic transverse computed tomography scans were acquired in ten anaesthetized, surfactant-depleted pigs with preserved spontaneous breathing, as ventilator support was lowered by sequentially reducing inspiratory pressure and positive end expiratory pressure in steps. The volumes of gas and atelectasis in the lungs were correlated with PL obtained using oesophageal pressure recordings. Work of breathing (WOB) was assessed from Campbell diagrams.

    Results

    Gradual decrease in PL in both end-expiration and end-inspiration caused a proportional increase in atelectasis and decrease in the gas content (linear mixed model with an autoregressive correlation matrix; P < 0.001) as the WOB increased. However, cyclic alveolar collapse during tidal ventilation did not increase significantly.

    Conclusion

    We found a proportional correlation between atelectasis and PL during the ‘weaning process’ in experimental mild lung injury. If confirmed in the clinical setting, a gradual tapering of ventilator support can be recommended for weaning without risk of sudden formation of atelectasis.

  • 8.
    Hedenstierna, Göran
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Clinical Physiology.
    Perchiazzi, Gaetano
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Hedenstierna laboratory.
    Meyhoff, Christian S
    Larsson, Anders
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Anaesthesiology and Intensive Care. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Hedenstierna laboratory.
    Who Can Make Sense of the WHO Guidelines to Prevent Surgical Site Infection?2017In: Anesthesiology, ISSN 0003-3022, E-ISSN 1528-1175, Vol. 126, no 5, p. 771-773Article in journal (Refereed)
  • 9.
    Höstman, Staffan
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Anaesthesiology and Intensive Care. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Hedenstierna laboratory.
    Kawati, Rafael
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Anaesthesiology and Intensive Care.
    Perchiazzi, Gaetano
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Hedenstierna laboratory. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Anaesthesiology and Intensive Care.
    Larsson, Anders
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Anaesthesiology and Intensive Care. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Hedenstierna laboratory.
    THAM administration reduces pulmonary carbon dioxide elimination in hypercapnia: an experimental porcine study2018In: Acta Anaesthesiologica Scandinavica, ISSN 0001-5172, E-ISSN 1399-6576, Vol. 62, no 6, p. 820-828Article in journal (Refereed)
    Abstract [en]

    Background: In a previous study, we found a rebound of arterial carbon dioxide tension (PaCO2) after stopping THAM buffer administration. We hypothesized that this was due to reduced pulmonary CO2 elimination during THAM administration. The aim of this study was to investigate this hypothesis in an experimental porcine hypercapnic model.

    Methods: In seven, initially normoventilated, anesthetized pigs (22-27 kg) minute ventilation was reduced by 66% for 7 h. Two hours after commencing hypoventilation, THAM was infused IV for 3 h in a dose targeting a pH of 7.35 followed by a 2 h observation period. Acid-base status, blood-gas content and exhaled CO2 were measured.

    Results: THAM raised pH (7.07 0.04 to 7.41 +/- 0.04, P < 0.05) and lowered PaCO2 (15.2 +/- 1.4 to 12.2 +/- 1.1 kPa, P < 0.05). After the infusion, pH decreased and PaCO2 increased again. At the end of the observation period, pH and PaCO2 were 7.24 +/- 0.03 and 16.6 +/- 1.2 kPa, respectively (P < 0.05). Pulmonary CO2 excretion decreased from 109 +/- 12 to 74 +/- 12 ml/min (P < 0.05) during the THAM infusion but returned at the end of the observation period to 111 +/- 15 ml/min (P < 0.05). The estimated reduction of pulmonary CO2 elimination during the infusion was 5800 ml.

    Conclusions: In this respiratory acidosis model, THAM reduced PaCO2, but seemed not to increase the total CO2 elimination due to decreased pulmonary CO2 excretion(,) suggesting only cautious use of THAM in hypercapnic acidosis.

  • 10.
    Karbing, D. S.
    et al.
    Aalborg Univ, Dept Hlth Sci & Technol, Resp & Crit Care Rcare, Aalborg, Denmark.
    Perchiazzi, Gaetano
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Hedenstierna laboratory.
    Rees, S. E.
    Aalborg Univ, Dept Hlth Sci & Technol, Resp & Crit Care Rcare, Aalborg, Denmark.
    Jaffe, M. B.
    Cardioresp Consulting LLC, Cheshire, CT USA.
    Journal of Clinical Monitoring and Computing 2017 end of year summary: respiration2018In: Journal of clinical monitoring and computing, ISSN 1387-1307, E-ISSN 1573-2614, Vol. 32, no 2, p. 197-205Article, review/survey (Refereed)
    Abstract [en]

    This paper reviews 32 papers or commentaries published in Journal of Clinical Monitoring and Computing in 2016, within the field of respiration. Papers were published covering airway management, ventilation and respiratory rate monitoring, lung mechanics and gas exchange monitoring, in vitro monitoring of lung mechanics, CO2 monitoring, and respiratory and metabolic monitoring techniques.

  • 11. Meyhoff, Christian S.
    et al.
    Larsson, Anders
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Hedenstierna laboratory. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Anaesthesiology and Intensive Care. Univ Hosp, Uppsala, Sweden.
    Perchiazzi, Gaetano
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Hedenstierna laboratory.
    Hedenstierna, Göran
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Hedenstierna laboratory.
    In Reply2018In: Anesthesiology, ISSN 0003-3022, E-ISSN 1528-1175, Vol. 128, no 1, p. 222-224Article in journal (Refereed)
  • 12.
    Pellegrini, Mariangela
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Hedenstierna laboratory. Univ Bari, Dept Emergency & Organ Transplant, Bari, Italy..
    Derosa, Savino
    Univ Bari, Dept Emergency & Organ Transplant, Bari, Italy..
    Tannoia, Angela
    Univ Bari, Dept Emergency & Organ Transplant, Bari, Italy..
    Rylander, Christian
    Sahlgrens Univ Hosp, Dept Anaesthesia & Intens Care Med, Gothenburg, Sweden..
    Fiore, Tommaso
    Univ Bari, Dept Emergency & Organ Transplant, Bari, Italy..
    Larsson, Anders
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Hedenstierna laboratory. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Anaesthesiology and Intensive Care.
    Hedenstierna, Göran
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Clinical Physiology.
    Perchiazzi, Gaetano
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Clinical Physiology. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Hedenstierna laboratory. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Anaesthesiology and Intensive Care. Univ Bari, Dept Emergency & Organ Transplant, Bari, Italy..
    Effects of superimposed tissue weight on regional compliance of injured lungs2016In: Respiratory Physiology & Neurobiology, ISSN 1569-9048, E-ISSN 1878-1519, Vol. 228, p. 16-24Article in journal (Refereed)
    Abstract [en]

    Computed tomography (CT), together with image analysis technologies, enable the construction of regional volume (V-REG) and local transpulmonary pressure (P-TP,P-REG) maps of the lung. Purpose of this study is to assess the distribution of V-REG vs P-TP,P-REG along the gravitational axis in healthy (HL) and experimental acute lung injury conditions (eALI) at various positive end-expiratory pressures (PEEPS) and inflation volumes. Mechanically ventilated pigs underwent inspiratory hold maneuvers at increasing volumes simultaneously with lung CT scans. eALI was induced via the iv administration of oleic acid. We computed voxel-level V-REG vs P-TP,P-REG curves into eleven isogravitational planes by applying polynomial regressions. Via F-test, we determined that V-REG vs P-TP,P-REG curves derived from different anatomical planes (p-values < 1.4E-3), exposed to different PEEPs (p-values < 1.5E-5) or subtending different lung status (p-values < 3E-3) were statistically different (except for two cases of adjacent planes). Lung parenchyma exhibits different elastic behaviors based on its position and the density of superimposed tissue which can increase during lung injury.

  • 13.
    Pellegrini, Mariangela
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Hedenstierna laboratory. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Anaesthesiology and Intensive Care.
    Hedenstierna, Göran
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Clinical Physiology. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Hedenstierna laboratory.
    Roneus, Agneta
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Hedenstierna laboratory. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Anaesthesiology and Intensive Care.
    Larsson, Anders S.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Anaesthesiology and Intensive Care. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Hedenstierna laboratory.
    Perchiazzi, Gaetano
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Hedenstierna laboratory. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Anaesthesiology and Intensive Care.
    Onset and Magnitude of Pendelluft During Spontaneous Breathing Depend on Lung Volume2018In: American Journal of Respiratory and Critical Care Medicine, ISSN 1073-449X, E-ISSN 1535-4970, Vol. 197Article in journal (Other academic)
  • 14.
    Pellegrini, Mariangela
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Hedenstierna laboratory. Univ Bari, Dept Emergency & Organ Transplant, Bari, Italy.
    Hedenstierna, Göran
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Hedenstierna laboratory. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Clinical Physiology.
    Roneus, Agneta
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Hedenstierna laboratory.
    Segelsjö, Monica
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Larsson, Anders
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Hedenstierna laboratory. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Anaesthesiology and Intensive Care.
    Perchiazzi, Gaetano
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Hedenstierna laboratory. Univ Bari, Dept Emergency & Organ Transplant, Bari, Italy.
    The Diaphragm Acts as a Brake During Expiration to Prevent Lung Collapse2017In: American Journal of Respiratory and Critical Care Medicine, ISSN 1073-449X, E-ISSN 1535-4970, Vol. 195, no 12, p. 1608-1616Article in journal (Refereed)
    Abstract [en]

    Rationale: The diaphragm is the major inspiratory muscle and is assumed to relax during expiration. However, electrical postinspiratory activity has been observed. Whether there is an expiratory diaphragmatic contraction that preserves lung patency has yet to be explored.

    Objectives: We hypothesized the occurrence of an expiratory diaphragmatic contraction directed at stabilizing peripheral airways and preventing or reducing cyclic expiratory lung collapse.

    Methods: Mild acute respiratory distress syndrome was induced in 10 anesthetized, spontaneously breathing pigs. Lung volume was decreased by lowering end-expiratory airway pressure in a stepwise manner. We recorded the diaphragmatic electric activity during expiration, dynamic computed tomographic scans, and respiratory mechanics. In five pigs, the same protocol was repeated during mechanical ventilation after muscle paralysis.

    Measurements and Main Results: Diaphragmatic electric activity during expiration increased by decreasing end-expiratory lung volume during spontaneous breathing. This enhanced the diaphragm muscle force, to a greater extent with lower lung volume, indicating a diaphragmatic electromechanical coupling during spontaneous expiration. In turn, the resulting diaphragmatic contraction delayed and reduced the expiratory collapse and increased lung aeration compared with mechanical ventilation with muscle paralysis and absence of diaphragmatic activity.

    Conclusions: The diaphragm is an important regulator of expiration. Its expiratory activity seems to preserve lung volume and to protect against lung collapse. The loss of diaphragmatic expiratory contraction during mechanical ventilation and muscle paralysis may be a contributing factor to unsuccessful respiratory support.

  • 15.
    Perchiazzi, G
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Hedenstierna laboratory. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Anaesthesiology and Intensive Care. Bari Univ, Dept Emergency & Organ Transplant, Bari, Italy.
    Rylander, Christian
    Sahlgrens Univ Hosp, Dept Anaesthesia & Intens Care Med, Gothenburg, Sweden.
    Pellegrini, Mariangela
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Hedenstierna laboratory. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Anaesthesiology and Intensive Care. Bari Univ, Dept Emergency & Organ Transplant, Bari, Italy.
    Larsson, Anders
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Anaesthesiology and Intensive Care. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Hedenstierna laboratory.
    Hedenstierna, Göran
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Hedenstierna laboratory. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Clinical Physiology.
    Robustness of two different methods of monitoring respiratory system compliance during mechanical ventilation.2017In: Medical and Biological Engineering and Computing, ISSN 0140-0118, E-ISSN 1741-0444, Vol. 55, no 10, p. 1819-1828Article in journal (Refereed)
    Abstract [en]

    Robustness measures the performance of estimation methods when they work under non-ideal conditions. We compared the robustness of artificial neural networks (ANNs) and multilinear fitting (MLF) methods in estimating respiratory system compliance (C RS) during mechanical ventilation (MV). Twenty-four anaesthetized pigs underwent MV. Airway pressure, flow and volume were recorded at fixed intervals after the induction of acute lung injury. After consecutive mechanical breaths, an inspiratory pause (BIP) was applied in order to calculate CRS using the interrupter technique. From the breath preceding the BIP, ANN and MLF had to compute CRS in the presence of two types of perturbations: transient sensor disconnection (TD) and random noise (RN). Performance of the two methods was assessed according to Bland and Altman. The ANN presented a higher bias and scatter than MLF during the application of RN, except when RN was lower than 2% of peak airway pressure. During TD, MLF algorithm showed a higher bias and scatter than ANN. After the application of RN, ANN and MLF maintain a stable performance, although MLF shows better results. ANNs have a more stable performance and yield a more robust estimation of C RS than MLF in conditions of transient sensor disconnection.

  • 16.
    Perchiazzi, Gaetano
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Hedenstierna laboratory. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Anaesthesiology and Intensive Care.
    Höstman, Staffan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Anaesthesiology and Intensive Care. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Hedenstierna laboratory.
    Kawati, Rafael
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Anaesthesiology and Intensive Care.
    Larsson, Anders
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Anaesthesiology and Intensive Care. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Hedenstierna laboratory.
    Tham Administration Reduces Pulmonary Carbon Dioxide Elimination, Causing Rebound In Arterial Carbon Dioxide Tension: An Experimental Study In Hypoventilated Pigs2017In: American Journal of Respiratory and Critical Care Medicine, ISSN 1073-449X, E-ISSN 1535-4970, Vol. 195, article id A7518Article in journal (Other academic)
  • 17.
    Perchiazzi, Gaetano
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Hedenstierna laboratory. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Anaesthesiology and Intensive Care.
    Pellegrini, Mariangela
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Hedenstierna laboratory. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Anaesthesiology and Intensive Care.
    Hedenstierna, Göran
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Clinical Physiology. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Hedenstierna laboratory.
    Roneus, Agneta
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Anaesthesiology and Intensive Care. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Hedenstierna laboratory.
    Larsson, Anders S.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Anaesthesiology and Intensive Care. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Hedenstierna laboratory.
    Multiple Transients of Local Gas Redistribution During Spontaneous Breathing Are Influenced by Ventilatory Settings2018In: American Journal of Respiratory and Critical Care Medicine, ISSN 1073-449X, E-ISSN 1535-4970, Vol. 197Article in journal (Other academic)
  • 18.
    Perchiazzi, Gaetano
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Hedenstierna laboratory.
    Pellegrini, Mariangela
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Hedenstierna laboratory.
    Lantz, Hannes
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Hedenstierna laboratory.
    Hedenstierna, Göran
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Hedenstierna laboratory. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Clinical Physiology.
    Larsson, Anders
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Anaesthesiology and Intensive Care. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Hedenstierna laboratory.
    High PEEP Reduces Recruitment/Derecruitment During Neurally Adjusted Ventilatory Assist in Mild Experimental ARDS2016In: American Journal of Respiratory and Critical Care Medicine, ISSN 1073-449X, E-ISSN 1535-4970, Vol. 193, article id A5226Article in journal (Other academic)
  • 19.
    Perchiazzi, Gaetano
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Clinical Physiology. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Hedenstierna laboratory.
    Rylander, Christian
    Derosa, Savino
    Pellegrini, Mariangela
    Pitagora, Loredana
    Polieri, Debora
    Vena, Antonio
    Tannoia, Angela
    Fiore, Tommaso
    Hedenstierna, Göran
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Clinical Physiology.
    Regional distribution of lung compliance by image analysis of computed tomograms2014In: Respiratory Physiology & Neurobiology, ISSN 1569-9048, E-ISSN 1878-1519, Vol. 201, p. 60-70Article in journal (Refereed)
    Abstract [en]

    Computed tomography (CT) can yield quantitative information about volume distribution in the lung. By combining information provided by CT and respiratory mechanics, this study aims at quantifying regional lung compliance (CL) and its distribution and homogeneity in mechanically ventilated pigs. The animals underwent inspiratory hold maneuvers at 12 lung volumes with simultaneous CT exposure at two end-expiratory pressure levels and before and after acute lung injury (ALI) by oleic acid administration. CL and the sum of positive voxel compliances from CT were linearly correlated; negative compliance areas were found. A remarkably heterogeneous distribution of voxel compliance was found in the injured lungs. As the lung inflation increased, the homogeneity increased in healthy lungs but decreased in injured lungs. Image analysis brought novel findings regarding spatial homogeneity of compliance, which increases in ALI but not in healthy lungs by applying PEEP after a recruitment maneuver.

  • 20.
    Perchiazzi, Gaetano
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Hedenstierna laboratory. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Anaesthesiology and Intensive Care. Department of Emergency and Organ Transplant, Section of Anaesthesia and Intensive Care Medicine, University of Bari, Italy.
    Rylander, Christian
    Pellegrini, Mariangela
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Hedenstierna laboratory. Department of Emergency and Organ Transplant, Section of Anaesthesia and Intensive Care Medicine, University of Bari, Italy.
    Larsson, Anders
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Hedenstierna laboratory. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Anaesthesiology and Intensive Care.
    Hedenstierna, Göran
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Hedenstierna laboratory. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Clinical Physiology.
    Monitoring of total positive end-expiratory pressure during mechanical ventilation by artificial neural networks2017In: Journal of clinical monitoring and computing, ISSN 1387-1307, E-ISSN 1573-2614, Vol. 31, no 3, p. 551-559Article in journal (Refereed)
    Abstract [en]

    Ventilation treatment of acute lung injury (ALI) requires the application of positive airway pressure at the end of expiration (PEEPapp) to avoid lung collapse. However, the total pressure exerted on the alveolar walls (PEEPtot) is the sum of PEEPapp and intrinsic PEEP (PEEPi), a hidden component. To measure PEEPtot, ventilation must be discontinued with an end-expiratory hold maneuver (EEHM). We hypothesized that artificial neural networks (ANN) could estimate the PEEPtot from flow and pressure tracings during ongoing mechanical ventilation. Ten pigs were mechanically ventilated, and the time constant of their respiratory system (τRS) was measured. We shortened their expiratory time (TE) according to multiples of τRS, obtaining different respiratory patterns (Rpat). Pressure (PAW) and flow (V'AW) at the airway opening during ongoing mechanical ventilation were simultaneously recorded, with and without the addition of external resistance. The last breath of each Rpat included an EEHM, which was used to compute the reference PEEPtot. The entire protocol was repeated after the induction of ALI with i.v. injection of oleic acid, and 382 tracings were obtained. The ANN had to extract the PEEPtot, from the tracings without an EEHM. ANN agreement with reference PEEPtot was assessed with the Bland-Altman method. Bland Altman analysis of estimation error by ANN showed -0.40 ± 2.84 (expressed as bias ± precision) and ±5.58 as limits of agreement (data expressed as cmH2O). The ANNs estimated the PEEPtot well at different levels of PEEPapp under dynamic conditions, opening up new possibilities in monitoring PEEPi in critically ill patients who require ventilator treatment.

  • 21.
    Rylander, C
    et al.
    Uppsala University, Medicinska vetenskapsområdet, Faculty of Medicine, Department of Medical Sciences.
    Högman, M
    Department of Medical Cell Biology.
    Perchiazzi, G
    Uppsala University, Medicinska vetenskapsområdet, Faculty of Medicine, Department of Medical Sciences.
    Magnusson, A
    Department of Oncology, Radiology and Clinical Immunology. Radiologi.
    Hedenstierna, G
    Uppsala University, Medicinska vetenskapsområdet, Faculty of Medicine, Department of Medical Sciences.
    Oleic acid lung injury: a morphometric analysis using computed tomography.2004In: Acta Anaesthesiol Scand, ISSN 0001-5172, Vol. 48, no 9, p. 1123-9Article in journal (Refereed)
  • 22.
    Rylander, Christian
    et al.
    Uppsala University, Medicinska vetenskapsområdet, Faculty of Medicine, Department of Medical Sciences.
    Högman, Marieann
    Department of Oncology, Radiology and Clinical Immunology.
    Perchiazzi, Gaetano
    Uppsala University, Medicinska vetenskapsområdet, Faculty of Medicine, Department of Medical Sciences.
    Magnusson, Anders
    Department of Oncology, Radiology and Clinical Immunology. Radiologi.
    Hedenstierna, Göran
    Uppsala University, Medicinska vetenskapsområdet, Faculty of Medicine, Department of Medical Sciences.
    Functional residual capacity and respiratory mechanics as indicators of aeration and collapse in experimental lung injury.2004In: Anesth Analg, ISSN 0003-2999, Vol. 98, no 3, p. 782-9, table of contentsArticle in journal (Refereed)
  • 23.
    Scaramuzzo, Gaetano
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Hedenstierna laboratory. Univ Ferrara, Dept Morphol Surg & Expt Med, Ferrara, Italy.
    Broche, Ludovic
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Hedenstierna laboratory. European Synchrotron Radiat Facil, Grenoble, France;Grenoble Alpes Univ, Synchrotron Radiat Biomed STROBE Lab, INSERM UA7, Amiens, France.
    Pellegrini, Mariangela
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Hedenstierna laboratory. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Anaesthesiology and Intensive Care.
    Porra, Liisa
    Univ Helsinki, Fac Math & Nat Sci, Dept Phys, Helsinki, Finland;Univ Helsinki, Cent Hosp, Helsinki, Finland.
    Derosa, Savino
    Univ Bari Aldo Moro, Dept Emergency & Organ Transplant, Bari, Italy.
    Tannoia, Angela Principia
    Univ Bari Aldo Moro, Dept Emergency & Organ Transplant, Bari, Italy.
    Marzullo, Andrea
    Univ Bari Aldo Moro, Dept Emergency & Organ Transplant, Bari, Italy.
    Batista Borges, João
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Hedenstierna laboratory. Kings Coll London, Fac Sci & Med, Ctr Human & Appl Physiol Sci, London, England.
    Bayat, Sam
    Grenoble Alpes Univ, Synchrotron Radiat Biomed STROBE Lab, INSERM UA7, Amiens, France.
    Bravin, Alberto
    European Synchrotron Radiat Facil, Grenoble, France.
    Larsson, Anders
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Hedenstierna laboratory.
    Perchiazzi, Gaetano
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Hedenstierna laboratory. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Anaesthesiology and Intensive Care.
    Regional Behavior of Airspaces During Positive Pressure Reduction Assessed by Synchrotron Radiation Computed Tomography2019In: Frontiers in Physiology, ISSN 1664-042X, E-ISSN 1664-042X, Vol. 10, article id 719Article in journal (Refereed)
    Abstract [en]

    Introduction: The mechanisms of lung inflation and deflation are only partially known. Ventilatory strategies to support lung function rely upon the idea that lung alveoli are isotropic balloons that progressively inflate or deflate and that lung pressure/volume curves derive only by the interplay of critical opening pressures, critical closing pressures, lung history, and position of alveoli inside the lung. This notion has been recently challenged by subpleural microscopy, magnetic resonance, and computed tomography (CT). Phase-contrast synchrotron radiation CT (PC-SRCT) can yield in vivo images at resolutions higher than conventional CT.

    Objectives: We aimed to assess the numerosity (ASden) and the extension of the surface of airspaces (ASext) in healthy conditions at different volumes, during stepwise lung deflation, in concentric regions of the lung. Methods: The study was conducted in seven anesthetized New Zealand rabbits. They underwent PC-SRCT scans (resolution of 47.7 mu m) of the lung at five decreasing positive end expiratory pressure (PEEP) levels of 12, 9, 6, 3, and 0 cmH(2)O during end-expiratory holds. Three concentric regions of interest (ROIs) of the lung were studied: subpleural, mantellar, and core. The images were enhanced by phase contrast algorithms. ASden and ASext were computed by using the Image Processing Toolbox for MatLab. Statistical tests were used to assess any significant difference determined by PEEP or ROI on ASden and ASext.

    Results: When reducing PEEP, in each ROI the ASden significantly decreased. Conversely, ASext variation was not significant except for the core ROI. In the latter, the angular coefficient of the regression line was significantly low.

    Conclusion: The main mechanism behind the decrease in lung volume at PEEP reduction is derecruitment. In our study involving lung regions laying on isogravitational planes and thus equally influenced by gravitational forces, airspace numerosity and extension of surface depend on the local mechanical properties of the lung.

1 - 23 of 23
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf