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Whitney J, Keir I. Clinical review of high-flow nasal oxygen therapy in human and veterinary patients. Front Vet Sci 2023; 10:1070881. [PMID: 36950541 PMCID: PMC10027015 DOI: 10.3389/fvets.2023.1070881] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2022] [Accepted: 02/02/2023] [Indexed: 03/08/2023] Open
Abstract
Oxygen therapy is the first-line treatment for hypoxemic acute respiratory failure. In veterinary medicine this has traditionally been provided via mask, low-flow nasal oxygen cannulas, oxygen cages and invasive positive pressure ventilation. Traditional non-invasive modalities are limited by the maximum flow rate and fraction of inspired oxygen (FiO2) that can be delivered, variability in oxygen delivery and patient compliance. The invasive techniques are able to provide higher FiO2 in a more predictable manner but are limited by sedation/anesthesia requirements, potential complications and cost. High-flow nasal oxygen therapy (HFNOT) represents an alternative to conventional oxygen therapy. This modality delivers heated and humidified medical gas at adjustable flow rates, up to 60 L/min, and FiO2, up to 100%, via nasal cannulas. It has been proposed that HFNOT improves pulmonary mechanics and reduces respiratory fatigue via reduction of anatomical dead space, provision of low-level positive end-expiratory pressure (PEEP), provision of constant FiO2 at rates corresponding to patient requirements and through improved patient tolerance. Investigations into the use of HFNOT in veterinary patients have increased in frequency since its clinical use was first reported in dogs with acute respiratory failure in 2016. Current indications in dogs include acute respiratory failure associated with pulmonary parenchymal disease, upper airway obstruction and carbon monoxide intoxication. The use of HFNOT has also been advocated in certain conditions in cats and foals. HFNOT is also being used with increasing frequency in the treatment of a widening range of conditions in humans. Although there remains conflict regarding its use and efficacy in some patient groups, overall these reports indicate that HFNOT decreases breathing frequency and work of breathing and reduces the need for escalation of respiratory support. In addition, they provide insight into potential future veterinary applications. Complications of HFNOT have been rarely reported in humans and animals. These are usually self-limiting and typically result in lower morbidity and mortality than those associated with invasive ventilation techniques.
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Lung aeration and volumes following alveolar recruitment maneuvers with three airway pressures in healthy anesthetized and mechanically ventilated Beagle dogs. Vet Anaesth Analg 2022; 49:443-451. [DOI: 10.1016/j.vaa.2022.06.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Revised: 06/21/2022] [Accepted: 06/24/2022] [Indexed: 01/17/2023]
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Pournajafian A, Sakhaeyan E, Rokhtabnak F, Alimian M, Ghodrati A, Jolousi M, Ghodraty MR. Comparison of Pressure and Volume-Controlled Mechanical Ventilation in Laparoscopic Bariatric Surgery: A Randomized Crossover Trial. Anesth Pain Med 2022; 12:e123270. [PMID: 35991780 PMCID: PMC9375959 DOI: 10.5812/aapm-123270] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2022] [Revised: 03/29/2022] [Accepted: 03/30/2022] [Indexed: 11/29/2022] Open
Abstract
Background The number of patients with obesity undergoing various surgeries is increasing annually, and ventilation problems are highly prevalent in these patients. Objectives We aimed to evaluate ventilation effectiveness with pressure-controlled (PC) and volume-controlled (VC) ventilation modes during laparoscopic bariatric surgery. Methods In this open-label randomized crossover clinical trial, 40 adult patients with morbid obesity candidates for laparoscopic bariatric surgery were assigned to VC-PC or PC-VC groups. Each patient received both ventilation modes sequentially for 15 min during laparoscopic surgery in a random sequence. Every 5 min, exhaled tidal volume, peak and mean airway pressure, oxygen saturation, heart rate, mean arterial pressure, and end-tidal CO2 were recorded. Blood gas analysis was done at the end of 15 min. Dynamic compliance, PaO2/FiO2 ratio, P (A-a) O2 gradient, respiratory dead space, and PaCO2-ETCO2 gradient were calculated according to the obtained results. Results The study included 40 patients with a mean age of 35.13 ± 9.06 years. There were no significant differences in peak and mean airway pressure, dynamic compliance, and hemodynamic parameters (P > 0.05). There was no significant difference between the two ventilation modes in pH, PaCO2, PaO2, PaO2/FIO2, dead space volume, and D (A-a) O2 at different time intervals (P > 0.05). Conclusions If low tidal volumes are used during adult laparoscopic bariatric surgery, mechanical ventilation with PC mode is not superior to VC mode.
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Affiliation(s)
- Alireza Pournajafian
- Anesthesiology & Pain Department, Faculty of Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Elmira Sakhaeyan
- Anesthesiology & Pain Department, Faculty of Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Faranak Rokhtabnak
- Anesthesiology & Pain Department, Faculty of Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Mahzad Alimian
- Anesthesiology & Pain Department, Faculty of Medicine, Iran University of Medical Sciences, Tehran, Iran
| | | | - Minoo Jolousi
- Anesthesiology & Pain Department, Faculty of Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Mohammad Reza Ghodraty
- Anesthesiology & Pain Department, Faculty of Medicine, Iran University of Medical Sciences, Tehran, Iran
- Corresponding Author: Anesthesiology & Pain Department, Faculty of Medicine, Iran University of Medical Sciences, Tehran, Iran.
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Bedside Selection of Positive End Expiratory Pressure by Electrical Impedance Tomography in Patients Undergoing Veno-Venous Extracorporeal Membrane Oxygenation Support: A Comparison between COVID-19 ARDS and ARDS from Other Etiologies. J Clin Med 2022; 11:jcm11061639. [PMID: 35329965 PMCID: PMC8955184 DOI: 10.3390/jcm11061639] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2022] [Revised: 03/09/2022] [Accepted: 03/14/2022] [Indexed: 12/14/2022] Open
Abstract
Background: The interest in protective ventilation strategies and individualized approaches for patients with severe illness on veno venous extracorporeal support has increased in recent years. Wide heterogeneity exists among patients with COVID-19 related acute respiratory distress syndrome (C-ARDS) and ARDS from other etiologies (NC-ARDS). EIT is a useful tool for the accurate analysis of regional lung volume distribution and allows for a tailored ventilatory setting. The aim of this work is to retrospectively describe the results of EIT assessments performed in patients C-ARDS and NC-ARDS undergoing V-V ECMO support. Methods: A clinical EIT-guided decremental PEEP trail was conducted for all patients included in the study and mechanically ventilated. Results: 12 patients with C-ARDS and 12 patients with NC-ARDS were included in the study for a total of 13 and 18 EIT evaluations, respectively. No significant differences in arterial blood gas, respiratory parameters, and regional ventilation before and after the EIT exam were recorded. The subset of patients with NC-ARDS whose EIT exam led to PEEP modification was characterized by a lower baseline compliance compared with the C-ARDS group: 18 (16–28) vs. 27 (24–30) (p = 0.04). Overdistension significantly increased at higher steps only for the NC-ARDS group. A higher percentage of overdistension was described in patients with NC-ARDS when compared with patients with C-ARDS. Conclusions: EIT is feasible in patients with COVID-19-associated ARDS on veno-venous extracorporeal support and may help in tailoring the PEEP setting. Overall, severe COVID-19-related ARDS presents respiratory characteristics similar to severe “classical” NC-ARDS. However, C-ARDS is associated with a lower risk of overdistension at a higher PEEP level compared with NC-ARDS.
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Definition and clinical evaluation of a recruiting airway pressure based on the specific lung elastance in anesthetized dogs. Vet Anaesth Analg 2021; 48:484-492. [PMID: 33926822 DOI: 10.1016/j.vaa.2021.03.005] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2020] [Revised: 03/15/2021] [Accepted: 03/16/2021] [Indexed: 11/23/2022]
Abstract
OBJECTIVE To determine the specific lung elastance (SEL) in anesthetized dogs and to evaluate the efficacy of a SEL-based recruiting airway pressure (RPaw) at improving global and regional lung aeration. STUDY DESIGN Retrospective and prospective clinical study. ANIMALS A total of 28 adult dogs were included in the retrospective study and six adult dogs in the prospective study. METHODS Retrospective study: SEL and SEL-based RPaw were determined using previously published data. In mechanically ventilated dogs undergoing thoracic computed tomography (CT), SEL was calculated as ΔPL/(VT/EELV), where ΔPL is the driving transpulmonary pressure, VT is the tidal volume and EELV is the end-expiratory lung volume. The ratio of lung to respiratory system elastance (EL/Ers) was determined. SEL and EL/Ers were used to calculate the SEL-based RPaw. Prospective study: dogs underwent thoracic CT at end-expiration and at end-inspiration using the SEL-based RPaw, and global and regional aeration was determined. For analysis of regional aeration, lungs were divided into cranial, intermediate and caudal regions. Regional compliance was also calculated. A p value <0.05 was considered significant. RESULTS The SEL and EL/Ers were 12.7 ± 3.1 cmH2O and 0.54 ± 0.07, respectively. The SEL-based RPaw was 29.1 ± 7.6 cmH2O. In the prospective study, the RPaw was 28.2 ± 1.3 cmH2O. During RPaw, hyperinflation increased (p = 0.0003) whereas poorly aerated (p < 0.0001) and nonaerated (p = 0.01) tissue decreased. Normally aerated tissue did not change (p = 0.265). Regional compliance was higher in the intermediate (p = 0.0003) and caudal (p = 0.034) regions compared with the cranial region. Aeration did not differ between regions (p > 0.05). CONCLUSIONS AND CLINICAL RELEVANCE An SEL-based RPaw reduces poorly and nonaerated lung tissue in anesthetized dogs. In nonsurgical anesthetized dogs, an RPaw near 30 cmH2O is effective at improving lung aeration.
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Effects of intra-operative positive end-expiratory pressure setting guided by oesophageal pressure measurement on oxygenation and respiratory mechanics during laparoscopic gynaecological surgery: A randomised controlled trial. Eur J Anaesthesiol 2020; 37:1032-1039. [PMID: 32371830 DOI: 10.1097/eja.0000000000001204] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
BACKGROUND The creation of pneumoperitoneum during laparoscopic surgery can lead to adverse effects on the respiratory system. Positive end-expiratory pressure (PEEP) plays an important role in mechanical ventilation during laparoscopic surgery. OBJECTIVE To evaluate whether PEEP setting guided by oesophageal pressure (Poeso) measurement would affect oxygenation and respiratory mechanics during laparoscopic gynaecological surgery. DESIGN A randomised controlled study. SETTING A single-centre trial from March 2018 to June 2018. PATIENTS Forty-four adult patients undergoing laparoscopic gynaecological surgery with anticipated duration of surgery more than 2 h. INTERVENTION PEEP set according to Poeso measurement (intervention group) versus PEEP constantly set at 5 cmH2O (control group). MAIN OUTCOME MEASURES Gas exchange and respiratory mechanics after induction and intubation (T0) and at 15 and 60 min after initiation of pneumoperitoneum (T1 and T2, respectively). RESULTS PEEP during pneumoperitoneum was significantly higher in the intervention group than in the control group (T1, 12.5 ± 1.9 vs. 5.0 ± 0.0 cmH2O and T2, 12.4 ± 1.9 vs. 5.0 ± 0.0 cmH2O, both P < 0.001). Partial pressures of oxygen decreased significantly from baseline during pneumoperitoneum in the control group but not in the intervention group. Nevertheless, the changes in partial pressures of oxygen did not differ between groups. Compliance of the respiratory system (CRS) significantly decreased and driving pressure significantly increased during pneumoperitoneum in both groups. However, the changes in CRS and driving pressure were significantly less in the intervention group. Transpulmonary pressure during expiration was maintained in the intervention group while it decreased significantly in the control group. CONCLUSION PEEP setting guided by Poeso measurement showed no beneficial effects in terms of oxygenation but respiratory mechanics were better during laparoscopic gynaecological surgery. TRIAL REGISTRATION ClinicalTrials.gov identifier: NCT03256396.
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Nabian M, Narusawa U. Patient-specific optimization of mechanical ventilation for patients with acute respiratory distress syndrome using quasi-static pulmonary P-V data. INFORMATICS IN MEDICINE UNLOCKED 2018; 12:44-55. [PMID: 35036518 PMCID: PMC8740849 DOI: 10.1016/j.imu.2018.06.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2018] [Revised: 06/05/2018] [Accepted: 06/06/2018] [Indexed: 11/13/2022] Open
Abstract
Quasi-static, pulmonary pressure-volume (P-V) curves were combined with a respiratory system model to analyze tidal pressure cycles, simulating mechanical ventilation of patients with acute respiratory distress syndrome (ARDS). Two important quantities including 1) tidal recruited volume and 2) tidal hyperinflated volume were analytically computed by integrating the distribution of alveolar elements over the affected pop-open pressure range. We analytically predicted the tidal recruited volume of four canine subjects and compared our results with similar experimental measurements on canine models for the validation. We then applied our mathematical model to the P-V data of ARDS populations in four stages of Early ARDS, Deep Knee, Advanced ARDS and Baby Lung to quantify the tidal recruited volume and tidal hyperinflated volume as an indicator of ventilator-induced lung injury (VILI). These quantitative predictions based on patient-specific P-V data suggest that the optimum parameters of mechanical ventilation including PEEP and Tidal Pressure (Volume) are largely varying among ARDS population and are primarily influenced by the degree in the severity of ARDS.
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Affiliation(s)
- Mohsen Nabian
- Department of Mechanical and Industrial Engineering, Northeastern University, Boston, MA, USA
| | - Uichiro Narusawa
- Department of Mechanical and Industrial Engineering, Northeastern University, Boston, MA, USA
- Department of Bio-engineering, Northeastern University, Boston, MA, USA
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Lovas A, Németh MF, Trásy D, Molnár Z. Lung recruitment can improve oxygenation in patients ventilated in continuous positive airway pressure/pressure support mode. Front Med (Lausanne) 2015; 2:25. [PMID: 25954744 PMCID: PMC4404945 DOI: 10.3389/fmed.2015.00025] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2015] [Accepted: 04/05/2015] [Indexed: 11/28/2022] Open
Abstract
Background Recruitment maneuvers are often used in critical care patients with hypoxemic respiratory failure. Although continuous positive airway pressure/pressure support (CPAP/PS) ventilation is a frequently used approach, but whether lung recruitment also improves oxygenation in spontaneously breathing patients has not been investigated yet. The primary objective was to analyze the effect of recruitment maneuver on oxygenation in patients ventilated in CPAP/PS mode. Methods Following baseline measurements PEEP was increased by 5 cmH2O. Recruitment maneuver was applied for 40 s with 40 cmH2O of PS. Measurements of the difference in PaO2/FiO2 and airway parameters measured by the ventilator were recorded immediately after recruitment then 15 and 30 min later. Thirty patients ventilated in CPAP/PS mode with a PEEP ≥5 cmH2O were enrolled in this prospective, observational study if their PaO2/FiO2 ratio was <300 mmHg or required an FiO2 >0.5. Results Following recruitment maneuver patients were considered as non-responders (NR, n = 15) if difference of PaO2/FiO2 <20% and responders (R, n = 15) if difference of PaO2/FiO2 ≥20%. In the NR-group, PaO2/FiO2 decreased non-significantly from baseline: median [interquartile], PaO2/FiO2 = 176 [120–186] vs. after recruitment: 169 [121–182] mmHg, P = 0.307 while in the R-group there was significant improvement: 139 [117–164] vs. 230 [211–323] mmHg, P = 0.01. At the same time points, dead space to tidal volume ratio (Vds/Vte) significantly increased in the NR-group Vds/Vte = 32 [27–37] vs. 36 [25–42]%, P = 0.013 but no significant change was observed in the R-group: 26 [22–34] vs. 27 [24–33]%, P = 0.386. Conclusion Recruitment maneuver improved PaO2/FiO2 ratio by ≥20% in 50% of patients ventilated in CPAP/PS mode.
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Affiliation(s)
- András Lovas
- Department of Anaesthesiology and Intensive Therapy, Faculty of Medicine, University of Szeged , Szeged , Hungary
| | - Márton Ferenc Németh
- Department of Anaesthesiology and Intensive Therapy, Faculty of Medicine, University of Szeged , Szeged , Hungary
| | - Domonkos Trásy
- Department of Anaesthesiology and Intensive Therapy, Faculty of Medicine, University of Szeged , Szeged , Hungary
| | - Zsolt Molnár
- Department of Anaesthesiology and Intensive Therapy, Faculty of Medicine, University of Szeged , Szeged , Hungary
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Frerichs I, Dargaville PA, Rimensberger PC. Regional respiratory inflation and deflation pressure–volume curves determined by electrical impedance tomography. Physiol Meas 2013; 34:567-77. [DOI: 10.1088/0967-3334/34/6/567] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Carlisle HR, Armstrong RK, Davis PG, Schibler A, Frerichs I, Tingay DG. Regional distribution of blood volume within the preterm infant thorax during synchronised mechanical ventilation. Intensive Care Med 2010; 36:2101-8. [DOI: 10.1007/s00134-010-2049-4] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2009] [Accepted: 07/19/2010] [Indexed: 11/30/2022]
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Ragaller M, Richter T. Acute lung injury and acute respiratory distress syndrome. J Emerg Trauma Shock 2010; 3:43-51. [PMID: 20165721 PMCID: PMC2823143 DOI: 10.4103/0974-2700.58663] [Citation(s) in RCA: 91] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2009] [Accepted: 10/30/2009] [Indexed: 01/11/2023] Open
Abstract
Every year, more information accumulates about the possibility of treating patients with acute lung injury or acute respiratory distress syndrome with specially designed mechanical ventilation strategies. Ventilator modes, positive end-expiratory pressure settings, and recruitment maneuvers play a major role in these strategies. However, what can we take from these experimental and clinical data to the clinical practice? In this article, we discuss substantial options of mechanical ventilation together with some adjunctive therapeutic measures, such as prone positioning and inhalation of nitric oxide.
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Affiliation(s)
- Maximillian Ragaller
- Department of Anesthesiology and Intensive Care Medicine, University Hospital Carl Gustav Carus, Dresden, Germany
| | - Torsten Richter
- Department of Anesthesiology and Intensive Care Medicine, University Hospital Carl Gustav Carus, Dresden, Germany
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[Peri-operative atelectasis and alveolar recruitment manoeuvres]. Arch Bronconeumol 2009; 46:317-24. [PMID: 19959274 DOI: 10.1016/j.arbres.2009.10.010] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2009] [Revised: 10/08/2009] [Accepted: 10/10/2009] [Indexed: 10/20/2022]
Abstract
Respiratory complications are a significant cause of post-operative morbidity and mortality. Peri-operative atelectasis, in particular, affects 90% of surgical patients and its effects can be prolonged, due to changes in respiratory mechanics, pulmonary circulation and hypoxaemia. Alveolar collapse is caused by certain predisposing factors, mainly by compression and absorption mechanisms. To prevent or treat these atelectasis several therapeutic strategies have been proposed, such as alveolar recruitment manoeuvres, which has become popular in the last few years. Its application in patients with alveolar collapse, but without a previous significant acute lung lesion, has some special features, therefore its use is not free of uncertainties and complications. This review describes the frequency, pathophysiology, importance and treatment of peri-operative atelectasis. Special attention is paid to treatment with recruitment manoeuvres, with the purpose of providing a basis for the their rational and appropriate use.
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Carvalho ARS, Jandre FC, Pino AV, Bozza FA, Salluh J, Rodrigues R, Ascoli FO, Giannella-Neto A. Positive end-expiratory pressure at minimal respiratory elastance represents the best compromise between mechanical stress and lung aeration in oleic acid induced lung injury. CRITICAL CARE : THE OFFICIAL JOURNAL OF THE CRITICAL CARE FORUM 2008; 11:R86. [PMID: 17688701 PMCID: PMC2206498 DOI: 10.1186/cc6093] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/05/2007] [Revised: 04/03/2007] [Accepted: 08/09/2007] [Indexed: 11/10/2022]
Abstract
INTRODUCTION Protective ventilatory strategies have been applied to prevent ventilator-induced lung injury in patients with acute lung injury (ALI). However, adjustment of positive end-expiratory pressure (PEEP) to avoid alveolar de-recruitment and hyperinflation remains difficult. An alternative is to set the PEEP based on minimizing respiratory system elastance (Ers) by titrating PEEP. In the present study we evaluate the distribution of lung aeration (assessed using computed tomography scanning) and the behaviour of Ers in a porcine model of ALI, during a descending PEEP titration manoeuvre with a protective low tidal volume. METHODS PEEP titration (from 26 to 0 cmH2O, with a tidal volume of 6 to 7 ml/kg) was performed, following a recruitment manoeuvre. At each PEEP, helical computed tomography scans of juxta-diaphragmatic parts of the lower lobes were obtained during end-expiratory and end-inspiratory pauses in six piglets with ALI induced by oleic acid. The distribution of the lung compartments (hyperinflated, normally aerated, poorly aerated and non-aerated areas) was determined and the Ers was estimated on a breath-by-breath basis from the equation of motion of the respiratory system using the least-squares method. RESULTS Progressive reduction in PEEP from 26 cmH2O to the PEEP at which the minimum Ers was observed improved poorly aerated areas, with a proportional reduction in hyperinflated areas. Also, the distribution of normally aerated areas remained steady over this interval, with no changes in non-aerated areas. The PEEP at which minimal Ers occurred corresponded to the greatest amount of normally aerated areas, with lesser hyperinflated, and poorly and non-aerated areas. Levels of PEEP below that at which minimal Ers was observed increased poorly and non-aerated areas, with concomitant reductions in normally inflated and hyperinflated areas. CONCLUSION The PEEP at which minimal Ers occurred, obtained by descending PEEP titration with a protective low tidal volume, corresponded to the greatest amount of normally aerated areas, with lesser collapsed and hyperinflated areas. The institution of high levels of PEEP reduced poorly aerated areas but enlarged hyperinflated ones. Reduction in PEEP consistently enhanced poorly or non-aerated areas as well as tidal re-aeration. Hence, monitoring respiratory mechanics during a PEEP titration procedure may be a useful adjunct to optimize lung aeration.
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Affiliation(s)
- Alysson Roncally S Carvalho
- Biomedical Engineering Program, COPPE, Federal University of Rio de Janeiro, Av. Horácio Macedo, CT Bloco H-327, 2030, 21941-914, Rio de Janeiro, Brazil
| | - Frederico C Jandre
- Biomedical Engineering Program, COPPE, Federal University of Rio de Janeiro, Av. Horácio Macedo, CT Bloco H-327, 2030, 21941-914, Rio de Janeiro, Brazil
| | - Alexandre V Pino
- Biomedical Engineering Program, COPPE, Federal University of Rio de Janeiro, Av. Horácio Macedo, CT Bloco H-327, 2030, 21941-914, Rio de Janeiro, Brazil
| | - Fernando A Bozza
- Fundação Oswaldo Cruz, Instituto de Pesquisa Clinica Evandro Chagas e Laboratório de Imunofarmacologia, IOC, Av Brasil, 4365, Manguinhos, 21045-900 Rio de Janeiro, Brazil
| | - Jorge Salluh
- National Institute of Cancer-1, ICU, Praça Cruz Vermelha, 20230-130 Rio de Janeiro, Brazil
| | - Rosana Rodrigues
- Radiodiagnostic Service, Clementino Fraga Filho Hospital, Federal University of Rio de Janeiro, R Professor Rodolpho Paulo Rocco, 255, 21-941-913 Rio de Janeiro, Brazil
| | - Fabio O Ascoli
- Fundação Oswaldo Cruz, Instituto de Pesquisa Clinica Evandro Chagas e Laboratório de Imunofarmacologia, IOC, Av Brasil, 4365, Manguinhos, 21045-900 Rio de Janeiro, Brazil
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Caironi P, Langer T, Gattinoni L. Acute lung injury/acute respiratory distress syndrome pathophysiology: what we have learned from computed tomography scanning. Curr Opin Crit Care 2008; 14:64-9. [DOI: 10.1097/mcc.0b013e3282f42d8c] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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