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1.
Physiol Meas ; 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38749458

RESUMO

OBJECTIVE: Diagnosis of incipient acute hypovolemia is challenging as vital signs are typically normal and patients remain asymptomatic at early stages. The early identification of this entity would affect patients' outcome if physicians were able to treat it precociously. Thus, the development of a noninvasive, continuous bedside monitoring tool to detect occult hypovolemia before patients become hemodynamically unstable is clinically relevant. We hypothesize that pulse oximeter's alternant (AC) and continuous (DC) components of the infrared light are sensitive to acute and small changes in patient's volemia. We aimed to test this hypothesis in a cohort of healthy blood donors as a model of slight hypovolemia. APPROACH: We planned to prospectively study blood donor volunteers removing 450 mL of blood in supine position. Noninvasive arterial blood pressure, heart rate, and finger pulse oximetry were recorded. Data was analyzed before donation, after donation and during blood auto-transfusion generated by the passive leg-rising maneuver. MAIN RESULTS: Sixty-six volunteers (44% women) accomplished the protocol successfully. No clinical symptoms of hypovolemia, arterial hypotension (systolic pressure <90 mmHg), brady-tachycardia (heart rate <60 and >100 beats-per-minute) or hypoxemia (SpO2 <90%) were observed during donation. The AC signal before donation (median 0.21 and interquartile range 0.17 a.u.) increased after donation [0.26(0.19) a.u; p<0.001]. The DC signal before donation [94.05(3.63) a.u] increased after blood extraction [94.65(3.49) a.u; p<0.001]. When the legs' blood was auto-transfused during the passive leg-rising, the AC [0.21(0.13) a.u.; p=0.54] and the DC [94.25(3.94) a.u.; p=0.19] returned to pre-donation levels. Significance. The AC and DC components of finger pulse oximetry changed during blood donation in asymptomatic volunteers. The continuous monitoring of these signals could be helpful in detecting occult acute hypovolemia. New pulse oximeters should be developed combining the AC/DC signals with a functional hemodynamic monitoring of fluid responsiveness to define which patient needs fluid administration. .

3.
Physiol Meas ; 45(3)2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38422512

RESUMO

Objective. Since pulse wave transit time (PWTT) shortens as pulmonary artery pressure (PAP) increases it was suggested as a potential non-invasive surrogate for PAP. The state of tidal lung filling is also known to affect PWTT independently of PAP. The aim of this retrospective analysis was to test whether respiratory gating improved the correlation coefficient between PWTT and PAP.Approach. In each one of five anesthetized and mechanically ventilated pigs two high-fidelity pressure catheters were placed, one directly behind the pulmonary valve, and the second one in a distal branch of the pulmonary artery. PAP was raised using the thromboxane A2 analogue U46619 and animals were ventilated in a pressure controlled mode (I:E ratio 1:2, respiratory rate 12/min, tidal volume of 6 ml kg-1). All signals were recorded using the multi-channel platform PowerLab®. The arrival of the pulse wave at each catheter tip was determined using a MATLAB-based modified hyperbolic tangent algorithm and PWTT calculated as the time interval between these arrivals.Main results. Correlation coefficient for PWTT and mean PAP wasr= 0.932 for thromboxane. This correlation coefficient increased considerably when heart beats either at end-inspiration (r= 0.978) or at end-expiration (r= 0.985) were selected (=respiratory gating).Significance. The estimation of mean PAP from PWTT improved significantly when taking the respiratory cycle into account. Respiratory gating is suggested to improve for the estimation of PAP by PWTT.


Assuntos
Hipertensão Pulmonar , Animais , Suínos , Artéria Pulmonar , Estudos Retrospectivos , Frequência Cardíaca , Análise de Onda de Pulso , Pressão Sanguínea
4.
Sci Rep ; 13(1): 23001, 2023 12 27.
Artigo em Inglês | MEDLINE | ID: mdl-38155157

RESUMO

Small intestinal bacterial overgrowth and compositional changes of intestinal microbiota are pathomechanistic factors in liver cirrhosis leading to bacterial translocation and infectious complications. We analyzed the quantity and composition of duodenal bacterial DNA (bactDNA) in relation to bactDNA in blood and ascites of patients with liver cirrhosis. Duodenal fluid and corresponding blood and ascites samples from 103 patients with liver cirrhosis were collected. Non-liver disease patients (n = 22) served as controls. BactDNA was quantified by 16S-rRNA gene-based PCR. T-RFLP and 16S-rRNA amplicon sequencing were used to analyze bacterial composition. Duodenal bacterial diversity in cirrhosis was distinct to controls showing significantly higher abundances of Streptococcus, Enterococcus and Veillonella. Patients with bactDNA positive ascites revealed reduced spectrum of core microbiota with Streptococcus as key player of duodenal community and higher prevalence of Granulicatella proving presence of cirrhosis related intestinal dysbiosis. Regarding duodenal fluid bactDNA quantification, no significant differences were found between patients with cirrhosis and controls. Additionally, percentage of subjects with detectable bactDNA in blood did not differ between patients and controls. This study evaluated the diversity of bacterial DNA in different body specimens with potential implications on understanding how intestinal bacterial translocation may affect infectious complications in cirrhosis.


Assuntos
Ascite , Líquido Ascítico , Humanos , Ascite/complicações , DNA Bacteriano/análise , Líquido Ascítico/microbiologia , Cirrose Hepática/complicações , Bactérias/genética , Fibrose , RNA Ribossômico 16S/genética
5.
Swiss Med Wkly ; 153: 40102, 2023 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-37769636

RESUMO

BACKGROUND AND AIMS: The Swiss Autoimmune Hepatitis Cohort Study is a nationwide registry, initiated in 2017, that collects retrospective and prospective clinical data and biological samples from patients of all ages with autoimmune hepatitis treated at Swiss hepatology centres. Here, we report the analysis of the first 5 years of registry data. RESULTS: A total of 291 patients with autoimmune hepatitis have been enrolled, 30 of whom were diagnosed before 18 years of age and composed the paediatric cohort. Paediatric cohort: median age at diagnosis 12.5 years (range 1-17, interquartile range (IQR) 8-15), 16 (53%) girls, 6 (32%) with type 2 autoimmune hepatitis, 8 (27%) with autoimmune sclerosing cholangitis, 1 with primary biliary cholangitis variant syndrome, 4 (15%) with inflammatory bowel disease and 10 (41%) with advanced liver fibrosis at diagnosis. Adult cohort: median age at diagnosis 54 years (range 42-64, IQR 18-81), 185 (71%) women, 51 (20%) with primary biliary cholangitis variant syndrome, 22 (8%) with primary sclerosing cholangitis variant syndrome, 9 (4%) with inflammatory bowel disease and 66 (32%) with advanced liver fibrosis at diagnosis. The median follow-up time for the entire cohort was 5.2 years (IQR 3-9.3 years). Treatment in children: 29 (97%) children were initially treated with corticosteroids, 28 of whom received combination treatment with azathioprine. Budesonide was used in four children, all in combination with azathioprine. Mycophenolate mofetil was used in five children, all of whom had previously received corticosteroids and thiopurine. Treatment in adults (data available for 228 patients): 219 (96%) were treated with corticosteroids, mostly in combination with azathioprine. Predniso(lo)ne was the corticosteroid used in three-quarters of patients; the other patients received budesonide. A total of 78 (33%) patients received mycophenolate mofetil, 62 of whom had previously been treated with azathioprine. Complete biochemical response was achieved in 13 of 19 (68%) children and 137 of 182 (75%) adults with available follow-up data. All children were alive at the last follow-up, and none had undergone liver transplantation. Five (2%) adults underwent liver transplantation, two of whom had a fulminant presentation. Four (2%) adults with autoimmune hepatitis died (two from liver-associated causes). CONCLUSION: Patients with autoimmune hepatitis in Switzerland had clinical features similar to those in other cohorts. The proportion of patients diagnosed with primary biliary cholangitis variant syndrome was higher than expected. Autoimmune hepatitis was managed according to guidelines, except for the use of budesonide in a small proportion of paediatric patients. The outcomes were excellent, but the findings must be confirmed over a longer follow-up period.


Assuntos
Hepatite Autoimune , Doenças Inflamatórias Intestinais , Cirrose Hepática Biliar , Adulto , Humanos , Criança , Feminino , Lactente , Pré-Escolar , Adolescente , Pessoa de Meia-Idade , Masculino , Azatioprina/uso terapêutico , Estudos Retrospectivos , Hepatite Autoimune/complicações , Hepatite Autoimune/diagnóstico , Hepatite Autoimune/tratamento farmacológico , Estudos Prospectivos , Suíça/epidemiologia , Estudos de Coortes , Cirrose Hepática Biliar/complicações , Cirrose Hepática Biliar/tratamento farmacológico , Ácido Micofenólico/uso terapêutico , Cirrose Hepática , Doenças Inflamatórias Intestinais/tratamento farmacológico , Budesonida/uso terapêutico
6.
BMC Anesthesiol ; 23(1): 320, 2023 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-37726649

RESUMO

BACKGROUND AND GOAL OF STUDY: Pulse pressure variation (PPV) and stroke volume variation (SVV), which are based on the forces caused by controlled mechanical ventilation, are commonly used to predict fluid responsiveness. When PPV and SVV were introduced into clinical practice, volume-controlled ventilation (VCV) with tidal volumes (VT) ≥ 10 ml kg- 1 was most commonly used. Nowadays, lower VT and the use of pressure-controlled ventilation (PCV) has widely become the preferred type of ventilation. Due to their specific flow characteristics, VCV and PCV result in different airway pressures at comparable tidal volumes. We hypothesised that higher inspiratory pressures would result in higher PPVs and aimed to determine the impact of VCV and PCV on PPV and SVV. METHODS: In this self-controlled animal study, sixteen anaesthetised, paralysed, and mechanically ventilated (goal: VT 8 ml kg- 1) pigs were instrumented with catheters for continuous arterial blood pressure measurement and transpulmonary thermodilution. At four different intravascular fluid states (IVFS; baseline, hypovolaemia, resuscitation I and II), ventilatory and hemodynamic data including PPV and SVV were assessed during VCV and PCV. Statistical analysis was performed using U-test and RM ANOVA on ranks as well as descriptive LDA and GEE analysis. RESULTS: Complete data sets were available of eight pigs. VT and respiratory rates were similar in both forms. Heart rate, central venous, systolic, diastolic, and mean arterial pressures were not different between VCV and PCV at any IVFS. Peak inspiratory pressure was significantly higher in VCV, while plateau, airway and transpulmonary driving pressures were significantly higher in PCV. However, these higher pressures did not result in different PPVs nor SVVs at any IVFS. CONCLUSION: VCV and PCV at similar tidal volumes and respiratory rates produced PPVs and SVVs without clinically meaningful differences in this experimental setting. Further research is needed to transfer these results to humans.


Assuntos
Artérias , Respiração , Humanos , Animais , Suínos , Pressão Sanguínea , Determinação da Pressão Arterial , Catéteres
7.
Paediatr Anaesth ; 33(11): 973-982, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37403466

RESUMO

BACKGROUND: Volumetric capnography in healthy ventilated neonates showed deformed waveforms, which are supposedly due to technological limitations of flow and carbon dioxide sensors. AIMS: This bench study analyzed the role of apparatus dead space on the shape of capnograms in simulated neonates with healthy lungs. METHODS: We simulated mechanical breaths in neonates of 2, 2.5, and 3 kg of body weight using a neonatal volumetric capnography simulator. The simulator was fed by a fixed amount of carbon dioxide of 6 mL/kg/min. Such simulator was ventilated in a volume control mode using fixed ventilatory settings with a tidal volume of 8 mL/kg and respiratory rates of 40, 35, and 30 breaths per minute for the 2, 2.5 and 3 kg neonates, respectively. We tested the above baseline ventilation with and without an additional apparatus dead space of 4 mL. RESULTS: Simulations showed that adding the apparatus dead space to baseline ventilation increased the amount of re-inhaled carbon dioxide in all neonates: 0.16 ± 0.01 to 0.32 ± 0.03 mL (2 kg), 0.14 ± 0.02 to 0.39 ± 0.05 mL (2.5 kg), and 0.13 ± 0.01 to 0.36 ± 0.05 mL (3 kg); (p < .001). Apparatus dead space was computed as part of the airway dead space, and therefore, the ratio of airway dead space to tidal volume increased from 0.51 ± 0.04 to 0.68 ± 0.06, from 0.43 ± 0.04 to 0.62 ± 0.01 and from 0.38 ± 0.01 to 0.60 ± 0.02 in the 2, 2.5 and 3 kg simulated neonates, respectively (p < .001). Compared to baseline ventilation, adding apparatus dead space decreased the ratio of the volume of phase III to VT size from 31% to 11% (2 kg), from 40% to 16% (2.5 kg) and from 50% to 18% (3 kg); (p < .001). CONCLUSIONS: The addition of a small apparatus dead space artificially deformed the volumetric capnograms in simulated neonates with healthy lungs.


Assuntos
Dióxido de Carbono , Respiração Artificial , Recém-Nascido , Humanos , Espaço Morto Respiratório , Pulmão , Volume de Ventilação Pulmonar , Capnografia
8.
PLoS One ; 18(4): e0281585, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37018188

RESUMO

BACKGROUND: Despite the widespread use of glucocorticoids in inflammatory and autoimmune disorders, there is uncertainty about the safe cessation of long-term systemic treatment, as data from prospective trials are largely missing. Due to potential disease relapse or glucocorticoid-induced hypocortisolism, the drug is often tapered to sub-physiological doses rather than stopped when the underlying disease is clinically stable, increasing the cumulative drug exposure. Conversely, the duration of exposure to glucocorticoids should be minimized to lower the risk of side effects. METHODS: We designed a multicenter, randomized, triple-blinded, placebo-controlled trial to test the clinical noninferiority of abrupt glucocorticoid stop compared to tapering after ≥28 treatment days with ≥420 mg cumulative and ≥7.5 mg mean daily prednisone-equivalent dose. 573 adult patients treated systemically for various disorders will be included after their underlying disease has been stabilized. Prednisone in tapering doses or matching placebo is administered over 4 weeks. A 250 mg ACTH-test, the result of which will be revealed a posteriori, is performed at study inclusion; all patients are instructed on glucocorticoid stress cover dosing. Follow-up is for 6 months. The composite primary outcome measure is time to hospitalization, death, initiation of unplanned systemic glucocorticoid therapy, or adrenal crisis. Secondary outcomes include the individual components of the primary outcome, cumulative glucocorticoid doses, signs and symptoms of hypocortisolism, and the performance of the ACTH test in predicting the clinical outcome. Cox proportional hazard, linear, and logistic regression models will be used for statistical analysis. CONCLUSION: This trial aims to demonstrate the clinical noninferiority and safety of abrupt treatment cessation after ≥28 days of systemic glucocorticoid therapy in patients with stabilized underlying disease. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT03153527; EUDRA-CT: 2020-005601-48 https://clinicaltrials.gov/ct2/show/NCT03153527?term=NCT03153527&draw=2&rank=1.


Assuntos
Insuficiência Adrenal , Glucocorticoides , Adulto , Humanos , Insuficiência Adrenal/induzido quimicamente , Hormônio Adrenocorticotrópico , Glucocorticoides/efeitos adversos , Glucocorticoides/uso terapêutico , Estudos Multicêntricos como Assunto , Recidiva Local de Neoplasia/tratamento farmacológico , Prednisona/efeitos adversos , Prednisona/uso terapêutico , Estudos Prospectivos , Ensaios Clínicos Controlados Aleatórios como Assunto , Suspensão de Tratamento
9.
Simul Healthc ; 2023 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-36877685

RESUMO

METHODS: An infant lung simulator was fed with CO2 supplied by a mass flow controller (VCO2-IN) and ventilated using standard settings. A volumetric capnograph was placed between the endotracheal tube and the ventilatory circuit. We simulated ventilated babies of different body weights (2, 2.5, 3, and 5 kg) with a VCO2 ranging from 12 to 30 mL/min. The correlation coefficient (r2), bias, coefficient of variation (CV = SD/x × 100), and precision (2 × CV) between the VCO2-IN and the elimination of CO2 recorded by the capnograph (VCO2-OUT) were calculated. The quality of the capnogram's waveforms was compared with real ones belonging to anesthetized infants using an 8-point scoring system, where 6 points or greater meant that the simulated capnogram showed good, 5 to 3 points acceptable, and less than 3 points an unacceptable shape. RESULTS: The correlation between VCO2-IN and VCO2-OUT was r2 = 0.9953 (P < 0.001), with a bias of 0.16 (95% confidence intervals from 0.12 to 0.20) mL/min. The CV was 5% or less and the precision was 10% or less. All simulated capnograms showed similar shapes compared with real babies, scoring 6 points for 3 kg and 6.5 points for 2-, 2.5-, and 5-kg babies. CONCLUSIONS: The simulator of volumetric capnograms was reliable, accurate, and precise for simulating the CO2 kinetics of ventilated infants.

10.
Biomedicines ; 11(1)2023 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-36672690

RESUMO

Pulse wave transit time (PWTT) shortens as pulmonary artery pressure (PAP) increases and was therefore suggested as a surrogate parameter for PAP. The aim of this analysis was to reveal patterns and potential mechanisms of ventilation-induced periodic changes in PWTT under resting conditions. To measure both PWTT and PAP in five healthy pigs, two pulmonary artery Mikro-Tip™ catheters were inserted into the pulmonary vasculature: one with the tip placed in the pulmonary artery trunk, and a second one placed in a distal segment of the pulmonary artery. Animals received pressure-controlled mechanical ventilation. Ventilation-dependent changes were seen in both variables, PWTT and mean PAP; however, changes in PWTT were not synchronous with changes in PAP. Thus, plotting the value of PWTT for each heartbeat over the respective PAP revealed a characteristic hysteresis. At the beginning of inspiration, PAP rose while PWTT remained constant. During further inspiration, PWTT started to decrease rapidly as mPAP was about to reach its plateau. The same time course was observed during expiration: while mPAP approached its minimum, PWTT increased rapidly. During apnea this hysteresis disappeared. Thus, non-synchronous ventilation-induced changes in PWTT and PAP were found with inspiration causing a significant shortening of PWTT. Therefore, it is suggested that the respiratory cycle should be considered when using PWTT as a surrogate for PAP.

11.
Acta Anaesthesiol Scand ; 67(2): 185-194, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36268561

RESUMO

BACKGROUND: Gravity-dependent positioning therapy is an established concept in the treatment of severe acute respiratory distress syndrome and improves oxygenation in spontaneously breathing patients with hypoxemic acute respiratory failure. In patients with coronavirus disease 2019, this therapy seems to be less effective. Electrical impedance tomography as a point-of-care functional imaging modality for visualizing regional ventilation can possibly help identify patients who might benefit from positioning therapy and guide those maneuvers in real-time. Therefore, in this prospective observational study, we aimed to discover typical patterns in response to positioning maneuvers. METHODS: Distribution of ventilation in 10 healthy volunteers and in 12 patients with hypoxemic respiratory failure due to coronavirus disease 2019 was measured in supine, left, and right lateral positions using electrical impedance tomography. RESULTS: In this study, patients with coronavirus disease 2019 showed a variety of ventilation patterns, which were not predictable, whereas all but one healthy volunteer showed a typical and expected gravity-dependent distribution of ventilation with the body positions. CONCLUSION: Distribution of ventilation and response to lateral positioning is variable and thus unpredictable in spontaneously breathing patients with coronavirus disease 2019. Electrical impedance tomography might add useful information on the immediate reaction to postural maneuvers and should be elucidated further in clinical studies. Therefore, we suggest a customized individualized positioning therapy guided by electrical impedance tomography.


Assuntos
COVID-19 , Insuficiência Respiratória , Humanos , Impedância Elétrica , Tomografia/métodos , COVID-19/terapia , Respiração , Tomografia Computadorizada por Raios X
12.
United European Gastroenterol J ; 10(9): 940-957, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36459576

RESUMO

Diverticulosis and diverticular disease are ranked among the most common gastroenterological diseases and conditions. While for many years diverticulitis was found to be mainly an event occurring in the elder population, more recent work in epidemiology demonstrates increasing frequency in younger subjects. In addition, there is a noticeable trend towards more complicated disease. This may explain the significant increase in hospitalisations observed in recent years. It is not a surprise that the number of scientific studies addressing the clinical and socioeconomic consequences in the field is increasing. As a result, diagnosis and conservative as well as surgical management have changed in recent years. Diverticulosis, diverticular disease and diverticulitis are a complex entity and apparently an interdisciplinary challenge. To meet theses considerations the German Societies for Gastroenterology and Visceral Surgery decided to create joint guidelines addressing all aspects in a truely interdisciplinary fashion. The aim of the guideline is to summarise and to evaluate the current state of knowledge on diverticulosis and diverticular disease and to develop statements as well as recommendations to all physicians involved in the management of patients with diverticular disease.


Assuntos
Doenças Diverticulares , Humanos , Idoso , Doenças Diverticulares/diagnóstico , Doenças Diverticulares/cirurgia
13.
United European Gastroenterol J ; 10(9): 923-939, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36411504

RESUMO

Diverticulosis and diverticular disease are ranked among the most common gastroenterological diseases and conditions. While for many years diverticulitis was found to be mainly an event occurring in the elder population, more recent work in epidemiology demonstrates increasing frequency in younger subjects. In addition, there is a noticeable trend towards more complicated disease. This may explain the significant increase in hospitalisations observed in recent years. It is not a surprise that the number of scientific studies addressing the clinical and socioeconomic consequences in the field is increasing. As a result, diagnosis and conservative as well as surgical management have changed in recent years. Diverticulosis, diverticular disease and diverticulitis are a complex entity and apparently an interdisciplinary challenge. To meet theses considerations the German Societies for Gastroenterology and Visceral Surgery decided to create joint guidelines addressing all aspects in a truely interdisciplinary fashion. The aim of the guideline is to summarise and to evaluate the current state of knowledge on diverticulosis and diverticular disease and to develop statements as well as recommendations to all physicians involved in the management of patients with diverticular disease.


Assuntos
Doenças Diverticulares , Humanos , Idoso , Doenças Diverticulares/diagnóstico , Doenças Diverticulares/epidemiologia , Doenças Diverticulares/terapia
14.
Respir Care ; 67(8): 906-913, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35610029

RESUMO

BACKGROUND: To analyze the role of PEEP on dynamic relative regional strain (DRRS) in a model of ARDS, respective maps were generated by electrical impedance tomography (EIT). METHODS: Eight ARDS pigs submitted to PEEP steps of 0, 5, 10, and 15 cm H2O at fixed ventilation were evaluated by EIT images. DRRS was calculated as (VT-EIT/EELI)/(VT-EIT[15PEEP]/EELI[15PEEP]), where the tidal volume (VT)-EIT and end-expiratory lung impedance (EELI) are the tidal and end-expiratory change in lung impedance, respectively. The measurement at 15 PEEP was taken as reference (end-expiratory transpulmonary pressure > 0 cm H2O). The relationship between EIT variables (center of ventilation, EELI, and DRRS) and airway pressures was assessed with mixed-effects models using EIT measurements as dependent variables and PEEP as fixed-effect variable. RESULTS: At constant ventilation, respiratory compliance increased progressively with PEEP (lowest value at zero PEEP 10 ± 3 mL/cm H2O and highest value at 15 PEEP 16 ± 6 mL/cm H2O; P < .001), whereas driving pressure decreased with PEEP (highest value at zero PEEP 34 ± 6 cm H2O and lowest value at 15 PEEP 21 ± 4 cm H2O; P < .001). The mixed-effect regression models showed that the center of ventilation moved to dorsal lung areas with a slope of 1.81 (1.44-2.18) % points by each cm H2O of PEEP; P < .001. EELI increased with a slope of 0.05 (0.02-0.07) (arbitrary units) for each cm H2O of PEEP; P < .001. DRRS maps showed that local strain in ventral lung areas decreased with a slope of -0.02 (-0.24 to 0.15) with each cm H2O increase of PEEP; P < .001. CONCLUSIONS: EIT-derived DRRS maps showed high strain in ventral lung zones at low levels of PEEP. The findings suggest overdistention of the baby lung.


Assuntos
Respiração com Pressão Positiva , Síndrome do Desconforto Respiratório , Animais , Impedância Elétrica , Pulmão/diagnóstico por imagem , Modelos Teóricos , Respiração com Pressão Positiva/métodos , Síndrome do Desconforto Respiratório/diagnóstico por imagem , Síndrome do Desconforto Respiratório/terapia , Suínos , Volume de Ventilação Pulmonar , Tomografia/métodos , Tomografia Computadorizada por Raios X
16.
Physiol Meas ; 43(3)2022 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-35322796

RESUMO

Objective. A linear relationship between impedance change (ΔZ) measured by thoracic electrical impedance tomography (EIT) and tidal volume (VT) has been demonstrated. This study evaluated the agreement between the displayed VT calculated by the EIT software (VTEIT) and spirometry (VTSPIRO) after an indirect two-point calibration.Approach.The EIT software was programmed to execute a bedside two-point calibration from the subject-specific, linear equation defining the relationship between ΔZand VTSPIROand displaying VTEITbreath-by-breath in 20 neutered male, juvenile pigs. After EIT calibration VTs of 8, 12, 16 and 20 ml kg-1were applied to the lungs. VTEITand VTSPIROwere recorded and analysed using Bland-Altman plot for multiple subject measurements. Volumetric capnography (VCap) and spirometry data were explored as components of variance using multiple regression.Main results.A mean relative difference (bias) of 0.7% with 95% confidence interval (CI) of -10.4% to 10.7% were found between VTEITand VTSPIROfor the analysed data set. The variance in VTEITcould not be explained by any of the measured VCap or spirometry variables.Significance.The narrow CI estimated in this study allows the conclusion that EIT and its software can be used to measure and accurately convert ΔZinto mililitre VT at the bedside after applying an indirect two-point calibration.


Assuntos
Tomografia , Animais , Calibragem , Impedância Elétrica , Medidas de Volume Pulmonar/métodos , Masculino , Suínos , Volume de Ventilação Pulmonar , Tomografia/métodos
17.
Anaesthesiologie ; 71(6): 475-482, 2022 06.
Artigo em Alemão | MEDLINE | ID: mdl-34985550

RESUMO

BACKGROUND: The current naming of ventilation modes in anesthesiology and critical care is characterized by manufacturer-specific inconsistent acronyms. This is confusing for users and potentially life-threatening for patients. The standard, published in August 2021 in its German version as DIN EN ISO 19223:2021, aims to introduce a uniform classification with corresponding nomenclature. AIM OF THE WORK: To present the new standard and its consequences for the user. MATERIAL AND METHOD: Review and summary of DIN EN ISO 19223:2021 with a critical appraisal of its strengths and weaknesses. RESULTS: A simplified scheme shows the group classification of ventilation modes based on similar characteristics. These are further specified by additional variables. A reference table contrasts the new nomenclature of ventilation modes with those currently in use. Accordingly, the new classification scheme appears inconsistent and the variables are difficult to distinguish. CONCLUSION: Standardized terminology and semantics in respiratory care are necessary and desirable for error reduction. However, the recently presented standard fulfils these expectations only to some extent and in its current form will probably lead to further ambiguities and problems in the clinical routine. Accordingly, it is imperative that this first version of DIN EN ISO 19223:2021 be understood as the starting point for a discussion of its content, even outside the standards committees, so that its obvious weaknesses can be eradicated and the nomenclature made suitable for everyday use.


Assuntos
Respiração Artificial , Respiração , Cuidados Críticos , Humanos , Pulmão
18.
J Clin Monit Comput ; 36(4): 975-985, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-34386896

RESUMO

Respiratory failure due to SARS-CoV-2 may progress rapidly. During the course of COVID-19, patients develop an increased respiratory drive, which may induce high mechanical strain a known risk factor for Patient Self-Inflicted Lung Injury (P-SILI). We developed a novel Electrical Impedance Tomography-based approach to visualize the Dynamic Relative Regional Strain (DRRS) in SARS-CoV-2 positive patients and compared these findings with measurements in lung healthy volunteers. DRRS was defined as the ratio of tidal impedance changes and end-expiratory lung impedance within each pixel of the lung region. DRRS values of the ten patients were considerably higher than those of the ten healthy volunteers. On repeated examination, patterns, magnitude and frequency distribution of DRRS were reproducible and in line with the clinical course of the patients. Lung ultrasound scores correlated with the number of pixels showing DRRS values above the derived threshold. Using Electrical Impedance Tomography we were able to generate, for the first time, images of DRRS which might indicate P-SILI in patients suffering from COVID-19.Trial Registration This observational study was registered 06.04.2020 in German Clinical Trials Register (DRKS00021276).


Assuntos
COVID-19 , Tomografia , Impedância Elétrica , Humanos , Pulmão/diagnóstico por imagem , Respiração com Pressão Positiva/métodos , SARS-CoV-2 , Tomografia/métodos
19.
Visc Med ; 37(5): 372-382, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34722720

RESUMO

BACKGROUND: The worldwide proportion of overweight adults almost doubled from 22% in 1975 to 39% in 2016. Comparably, for the USA and Germany in 2016, the proportion was 68 and 56.8%, respectively. In Olmsted County, Minnesota, the prevalence of diverticulitis also doubled between 1980 and 2007, from 19 to 40%. Obesity substantially increases the risk of multiple gastrointestinal (GI) diseases and non-GI diseases. In a narrative review, we examined the evidence on whether obesity also increases the risk for the development of diverticulosis or diverticular disease and its outcome. SUMMARY: Evidence suggests that being overweight (body mass index ≥25 kg/m2) or obese (≥30 kg/m2), especially viscerally obese, is a risk factor for diverticulosis, diverticular disease and diverticulitis, diverticular bleeding, more severe or complicated disease, recurrent disease, and for worse outcomes after surgery. KEY MESSAGES: There is a well-founded association between overweight and diverticular disease as well as diverticulosis. It is not clear whether overweight per se or confounders linked with it are responsible for the association. However, means to fight the overweight and obesity epidemic might also help to reduce the prevalence of morbidity and mortality from diverticular disease.

20.
Biomedicines ; 9(9)2021 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-34572397

RESUMO

For the non-invasive assessment of pulmonary artery pressure (PAP), surrogates like pulse wave transit time (PWTT) have been proposed. The aim of this study was to invasively validate for which kind of PAP (systolic, mean, or diastolic) PWTT is the best surrogate parameter. To assess both PWTT and PAP in six healthy pigs, two pulmonary artery Mikro-Tip™ catheters were inserted into the pulmonary vasculature at a fixed distance: one in the pulmonary artery trunk, and a second one in a distal segment of the pulmonary artery. PAP was raised using the thromboxane A2 analogue U46619 (TXA) and by hypoxic vasoconstriction. There was a negative linear correlation between PWTT and systolic PAP (r = 0.742), mean PAP (r = 0.712) and diastolic PAP (r = 0.609) under TXA. During hypoxic vasoconstriction, the correlation coefficients for systolic, mean, and diastolic PAP were consistently higher than for TXA-induced pulmonary hypertension (r = 0.809, 0.778 and 0.734, respectively). Estimation of sPAP, mPAP, and dPAP using PWTT is feasible, nevertheless slightly better correlation coefficients were detected for sPAP compared to dPAP. In this study we establish the physiological basis for future methods to obtain PAP by non-invasively measured PWTT.

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