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Background: Bedside electrical impedance tomography could be useful to visualize evolving pulmonary perfusion distributions when acute respiratory distress syndrome worsens or in response to ventilatory and positional therapies. In experimental acute respiratory distress syndrome, this study evaluated the agreement of electrical impedance tomography and dynamic contrast-enhanced computed tomography perfusion distributions at two injury time points and in response to increased positive end-expiratory pressure (PEEP) and prone position., Methods: Eleven mechanically ventilated (VT 8 ml · kg-1) Yorkshire pigs (five male, six female) received bronchial hydrochloric acid (3.5 ml · kg-1) to invoke lung injury. Electrical impedance tomography and computed tomography perfusion images were obtained at 2 h (early injury) and 24 h (late injury) after injury in supine position with PEEP 5 and 10 cm H2O. In eight animals, electrical impedance tomography and computed tomography perfusion imaging were also conducted in the prone position. Electrical impedance tomography perfusion (QEIT) and computed tomography perfusion (QCT) values (as percentages of image total) were compared in eight vertical regions across injury stages, levels of PEEP, and body positions using mixed-effects linear regression. The primary outcome was agreement between QEIT and QCT, defined using limits of agreement and Pearson correlation coefficient., Results: Pao2/Fio2 decreased over the course of the experiment (healthy to early injury, -253 [95% CI, -317 to -189]; early to late injury, -88 [95% CI, -151 to -24]). The limits of agreement between QEIT and QCT were -4.66% and 4.73% for the middle 50% quantile of average regional perfusion, and the correlation coefficient was 0.88 (95% CI, 0.86 to 0.90]; P < 0.001). Electrical impedance tomography and computed tomography showed similar perfusion redistributions over injury stages and in response to increased PEEP. QEIT redistributions after positional therapy underestimated QCT in ventral regions and overestimated QCT in dorsal regions., Conclusions: Electrical impedance tomography closely approximated computed tomography perfusion measures in experimental acute respiratory distress syndrome, in the supine position, over injury progression and with increased PEEP. Further validation is needed to determine the accuracy of electrical impedance tomography in measuring perfusion redistributions after positional changes., (Copyright © 2023 American Society of Anesthesiologists. All Rights Reserved.)

Background: A protective intra-operative lung ventilation strategy has been widely recommended for laparoscopic surgery. However, there is no consensus regarding the optimal level of positive end-expiratory pressure (PEEP) and its effects during pneumoperitoneum. Electrical impedance tomography (EIT) has recently been introduced as a bedside tool to monitor lung ventilation in real-time., Objective: We hypothesised that individually titrated EIT-PEEP adjusted to the surgical intervention would improve respiratory mechanics during and after surgery., Design: Randomised controlled trial., Setting: First Medical Centre of Chinese PLA General Hospital, Beijing., Patients: Seventy-five patients undergoing robotic-assisted laparoscopic hepatobiliary and pancreatic surgery under general anaesthesia., Interventions: Patients were randomly assigned 2 : 1 to individualised EIT-titrated PEEP (PEEPEIT; n = 50) or traditional PEEP 5 cmH2O (PEEP5 cmH2O; n = 25). The PEEPEIT group received individually titrated EIT-PEEP during pneumoperitoneum. The PEEP5 cmH2O group received PEEP of 5 cmH2O during pneumoperitoneum., Main Outcome Measures: The primary outcome was respiratory system compliance during laparoscopic surgery. Secondary outcomes were individualised PEEP levels, oxygenation, respiratory and haemodynamic status, and occurrence of postoperative pulmonary complications (PPCs) within 7 days., Results: Compared with PEEP5 cmH2O, patients who received PEEPEIT had higher respiratory system compliance (mean values during surgery of 44.3 ± 11.3 vs. 31.9 ± 6.6, ml cmH2O-1; P < 0.001), lower driving pressure (11.5 ± 2.1 vs. 14.0 ± 2.4 cmH2O; P < 0.001), better oxygenation (mean PaO2/FiO2 427.5 ± 28.6 vs. 366.8 ± 36.4; P = 0.003), and less postoperative atelectasis (19.4 ± 1.6 vs. 46.3 ± 14.8 g of lung tissue mass; P = 0.003). Haemodynamic values did not differ significantly between the groups. No adverse effects were observed during surgery., Conclusion: Individualised PEEP by EIT may improve intra-operative pulmonary mechanics and oxygenation without impairing haemodynamic stability, and decrease postoperative atelectasis., Trial Registration: Chinese Clinical Trial Registry (www.chictr.org.cn) identifier: ChiCTR2100045166., (Copyright © 2023 European Society of Anaesthesiology and Intensive Care. Unauthorized reproduction of this article is prohibited.)

Objectives: Experimental models suggest that prone position and positive end-expiratory pressure (PEEP) homogenize ventral-dorsal ventilation distribution and regional respiratory compliance. However, this response still needs confirmation on humans. Therefore, this study aimed to assess the changes in global and regional respiratory mechanics in supine and prone positions over a range of PEEP levels in acute respiratory distress syndrome (ARDS) patients., Design: A prospective cohort study., Patients: Twenty-two intubated patients with ARDS caused by COVID-19 pneumonia., Interventions: Electrical impedance tomography and esophageal manometry were applied during PEEP titrations from 20 cm H 2 O to 6 cm H 2 O in supine and prone positions., Measurements: Global respiratory system compliance (Crs), chest wall compliance, regional lung compliance, ventilation distribution in supine and prone positions., Main Results: Compared with supine position, the maximum level of Crs changed after prone position in 59% of ARDS patients ( n = 13), of which the Crs decreased in 32% ( n = 7) and increased in 27% ( n = 6). To reach maximum Crs after pronation, PEEP was changed in 45% of the patients by at least 4 cm H 2 O. After pronation, the ventilation and compliance of the dorsal region did not consistently change in the entire sample of patients, increasing specifically in a subgroup of patients who showed a positive change in Crs when transitioning from supine to prone position. These combined changes in ventilation and compliance suggest dorsal recruitment postpronation. In addition, the subgroup with increased Crs postpronation demonstrated the most pronounced difference between dorsal and ventral ventilation distribution from supine to prone position ( p = 0.01), indicating heterogeneous ventilation distribution in prone position., Conclusions: Prone position modifies global respiratory compliance in most patients with ARDS. Only a subgroup of patients with a positive change in Crs postpronation presented a consistent improvement in dorsal ventilation and compliance. These data suggest that the response to pronation on global and regional mechanics can vary among ARDS patients, with some patients presenting more dorsal lung recruitment than others., (Copyright © 2023 The Authors. Published by Wolters Kluwer Health, Inc. on behalf of the Society of Critical Care Medicine.)

Background: The emerging challenges in the healthcare system require a vision for the future of respiratory care to ensure a successful transition to practice for new graduate respiratory therapists (RT). The nursing profession has recognized the need to acknowledge the successes and failures of graduates' transition to practice so that these programs can be continuously improved. The challenge is in identifying aspects of the transition to practice that may improve job satisfaction, retention, professional development, and patient care for RTs. This research aimed to explore the perceptions of new graduate RTs' experiences during their first year of practice and identify barriers and facilitators to a successful transition to practice., Methods: This qualitative descriptive study surveyed new graduate RTs who transitioned to practice from May 2019 to December 2021 at a New England academic medical center respiratory care department., Results: Twenty-eight new graduate RTs responses were included in the study. The majority of the respondents experienced a successful transition to practice; however, they faced many barriers. New graduate RTs reported that their orientation did not provide enough experience and exposure to gain confidence in critical skills and procedures. They also experienced stress due to COVID-19 and interpersonal relationships, felt overwhelmed by their workload, and were subject to negative workplace behavior., Conclusions: New graduate RTs experienced many barriers to their transition to practice. Respiratory care leadership should identify barriers faced by new graduate RTs during their transition to practice. A nurse residency model may provide a framework for RT transition-to-practice programs. Improving transition-to-practice programs for new graduate RTs and surveying their experiences may lead to an increase in job satisfaction, retention, and improved patient care., Competing Interests: The authors have disclosed no conflicts of interest., (Copyright © 2023 by Daedalus Enterprises.)

(1) The use of high-flow nasal cannula (HFNC) combined with frequent respiratory monitoring in patients with acute hypoxic respiratory failure due to COVID-19 has been shown to reduce intubation and mechanical ventilation. (2) This prospective, single-center, observational study included consecutive adult patients with COVID-19 pneumonia treated with a high-flow nasal cannula. Hemodynamic parameters, respiratory rate, inspiratory fraction of oxygen (F i O 2 ), saturation of oxygen (S p O 2 ), and the ratio of oxygen saturation to respiratory rate (ROX) were recorded prior to treatment initiation and every 2 h for 24 h. A 6-month follow-up questionnaire was also conducted. (3) Over the study period, 153 of 187 patients were eligible for HFNC. Of these patients, 80% required intubation and 37% of the intubated patients died in hospital. Male sex (OR = 4.65; 95% CI [1.28; 20.6], p = 0.03) and higher BMI (OR = 2.63; 95% CI [1.14; 6.76], p = 0.03) were associated with an increased risk for new limitations at 6-months after hospital discharge. (4) 20% of patients who received HFNC did not require intubation and were discharged alive from the hospital. Male sex and higher BMI were associated with poor long-term functional outcomes.

Plant-insect interactions are a determining factor for sustainable crop production. Although plants can resist or tolerate herbivorous insects to varying degrees, even with the use of pesticides, insects can reduce plant net productivity by as much as 20%, so sustainable strategies for pest control with less dependence on chemicals are needed. Selecting plants with optimal resistance and photosynthetic traits can help minimize damage and maintain productivity. Here, 27 landrace accessions of lima beans, Phaseolus lunatus L., from the Yucatan Peninsula were evaluated in the field for morphological resistance traits, photosynthetic characteristics, insect damage and seed yield. Variation was found in physical leaf traits (number, area, and dry mass of leaves; trichome density, specific leaf thickness and hardness) and in physiological traits (photosynthetic rate, stomatal conductance, intercellular carbon, water-use efficiency, and transpiration). Five accessions (JMC1325, JMC1288, JMC1339, JMC1208 and JMC1264) had the lowest index for cumulative damage with the highest seed yield, although RDA analysis uncovered two accessions (JMC1339, JMC1288) with strong positive association of seed yield and the cumulative damage index with leaf production, specific leaf area (SLA) and total leaf area. Leaf traits, including SLA and total leaf area are important drivers for optimizing seed yield. This study identified 12 important morphological and physiological leaf traits for selecting landrace accessions of P. lunatus for high yields (regardless of damage level) to achieve sustainable, environmentally safe crop production., Competing Interests: The authors declare there are no competing interests., (©2021 Ruiz-Santiago et al.)

Background: Increased pleural pressure affects the mechanics of breathing of people with class III obesity (BMI > 40 kg/m 2 )., Research Question: What are the acute effects of CPAP titrated to match pleural pressure on cardiopulmonary function in spontaneously breathing patients with class III obesity?, Study Design and Methods: We enrolled six participants with BMI within normal range (control participants, group I) and 12 patients with class III obesity (group II) divided into subgroups: IIa, BMI of 40 to 50 kg/m 2 ; and IIb, BMI of ≥ 50 kg/m 2 . The study was performed in two phases: in phase 1, participants were supine and breathing spontaneously at atmospheric pressure, and in phase 2, participants were supine and breathing with CPAP titrated to match their end-expiratory esophageal pressure in the absence of CPAP. Respiratory mechanics, esophageal pressure, and hemodynamic data were collected, and right heart function was evaluated by transthoracic echocardiography., Results: The levels of CPAP titrated to match pleural pressure in group I, subgroup IIa, and subgroup IIb were 6 ± 2 cmH 2 O, 12 ± 3 cmH 2 O, and 18 ± 4 cmH 2 O, respectively. In both subgroups IIa and IIb, CPAP titrated to match pleural pressure decreased minute ventilation (IIa, P = .03; IIb, P = .03), improved peripheral oxygen saturation (IIa, P = .04; IIb, P = .02), improved homogeneity of tidal volume distribution between ventral and dorsal lung regions (IIa, P = .22; IIb, P = .03), and decreased work of breathing (IIa, P < .001; IIb, P = .003) with a reduction in both the work spent to initiate inspiratory flow as well as tidal ventilation. In five hypertensive participants with obesity, BP decreased to normal range, without impairment of right heart function., Interpretation: In ambulatory patients with class III obesity, CPAP titrated to match pleural pressure decreased work of breathing and improved respiratory mechanics while maintaining hemodynamic stability, without impairing right heart function., Trial Registry: ClinicalTrials.gov; No.: NCT02523352; URL: www.clinicaltrials.gov., (Copyright © 2021. Published by Elsevier Inc.)

Background: Acute respiratory distress syndrome (ARDS) patients may present impaired in lung function and structure after hospital discharge that may be related to mechanical ventilation strategy. The aim of this study was to evaluate the association between functional and structural lung impairment, N-terminal-peptide type III procollagen (NT-PCP-III) and driving pressure during protective mechanical ventilation. It was a secondary analysis of data from randomized controlled trial that included patients with moderate/severe ARDS with at least one follow-up visit performed. We obtained serial measurements of plasma NT-PCP-III levels. Whole-lung computed tomography analysis and pulmonary function test were performed at 1 and 6 months of follow-up. A health-related quality of life survey after 6 months was also performed., Results: Thirty-three patients were enrolled, and 21 patients survived after 6 months. In extubation day an association between driving pressure and NT-PCP-III was observed. At 1 and 6 months forced vital capacity (FVC) was negatively correlated to driving pressure (p < 0.01). At 6 months driving pressure was associated with lower FVC independently on tidal volume, plateau pressure and baseline static respiratory compliance after adjustments (r 2  = 0.51, p = 0.02). There was a significant correlation between driving pressure and lung densities and nonaerated/poorly aerated lung volume after 6 months. Driving pressure was also related to general health domain of SF-36 at 6 months., Conclusion: Even in patients ventilated with protective tidal volume, higher driving pressure is associated with worse long-term pulmonary function and structure.

Importance: Perioperative lung-protective ventilation has been recommended to reduce pulmonary complications after cardiac surgery. The protective role of a small tidal volume (VT) has been established, whereas the added protection afforded by alveolar recruiting strategies remains controversial., Objective: To determine whether an intensive alveolar recruitment strategy could reduce postoperative pulmonary complications, when added to a protective ventilation with small VT., Design, Setting, and Participants: Randomized clinical trial of patients with hypoxemia after cardiac surgery at a single ICU in Brazil (December 2011-2014)., Interventions: Intensive recruitment strategy (n=157) or moderate recruitment strategy (n=163) plus protective ventilation with small VT., Main Outcomes and Measures: Severity of postoperative pulmonary complications computed until hospital discharge, analyzed with a common odds ratio (OR) to detect ordinal shift in distribution of pulmonary complication severity score (0-to-5 scale, 0, no complications; 5, death). Prespecified secondary outcomes were length of stay in the ICU and hospital, incidence of barotrauma, and hospital mortality., Results: All 320 patients (median age, 62 years; IQR, 56-69 years; 125 women [39%]) completed the trial. The intensive recruitment strategy group had a mean 1.8 (95% CI, 1.7 to 2.0) and a median 1.7 (IQR, 1.0-2.0) pulmonary complications score vs 2.1 (95% CI, 2.0-2.3) and 2.0 (IQR, 1.5-3.0) for the moderate strategy group. Overall, the distribution of primary outcome scores shifted consistently in favor of the intensive strategy, with a common OR for lower scores of 1.86 (95% CI, 1.22 to 2.83; P = .003). The mean hospital stay for the moderate group was 12.4 days vs 10.9 days in the intensive group (absolute difference, -1.5 days; 95% CI, -3.1 to -0.3; P = .04). The mean ICU stay for the moderate group was 4.8 days vs 3.8 days for the intensive group (absolute difference, -1.0 days; 95% CI, -1.6 to -0.2; P = .01). Hospital mortality (2.5% in the intensive group vs 4.9% in the moderate group; absolute difference, -2.4%, 95% CI, -7.1% to 2.2%) and barotrauma incidence (0% in the intensive group vs 0.6% in the moderate group; absolute difference, -0.6%; 95% CI, -1.8% to 0.6%; P = .51) did not differ significantly between groups., Conclusions and Relevance: Among patients with hypoxemia after cardiac surgery, the use of an intensive vs a moderate alveolar recruitment strategy resulted in less severe pulmonary complications while in the hospital., Trial Registration: clinicaltrials.gov Identifier: NCT01502332.

Carapa guianensis, a popular medicinal plant known as "Andiroba" in Brazil, has been used in traditional medicine as an insect repellent and anti-inflammatory product. Additionally, this seed oil has been reported in the literature as a repellent against Aedes aegypti. The aim of this work is to report on the emulsification of vegetable oils such as "Andiroba" oil by using a blend of nonionic surfactants (Span 80® and Tween 20®), using the critical hydrophilic-lipophilic balance (HLB) and pseudo-ternary diagram as tools to evaluate the system's stability. The emulsions were prepared by the inverse phase method. Several formulations were made according to a HLB spreadsheet design (from 4.3 to 16.7), and the products were stored at 25°C and 4°C. The emulsion stabilities were tested both long- and short-term, and the more stable one was used for the pseudo-ternary diagram study. The emulsions were successfully obtained by a couple of surfactants, and the HLB analysis showed that the required HLB of the oil was 16.7. To conclude, the pseudo-ternary diagram identified several characteristic regions such as emulsion, micro-emulsion, and separation of phases.

Background: Investigations in the field of pharmaceutical analysis and quality control of medicines require analytical procedures that achieve suitable performance. An analytical curve is one of the most important steps in the chemical analysis presenting a direct relationship to features such as linearity., Objective: This study has the aim of developing a new methodology, the stationary cuvette, to derive analytical curves by spectroscopy for drug analysis., Methodology: The method consists basically of the use of a cuvette with a path length of 10 cm, containing a constant volume of solvent in which increasing amounts of a stock solution of the sample are added, droplet by droplet. After each addition, the cuvette is stirred and the absorbance is measured. This procedure was compared with the currently used methodology, which requires a labour-intensive dilution process, and possible sources of variation between them were evaluated., Results: The results demonstrated that the proposed technique presented high sensitivity and similar reproducibility compared with the conventional methodology. In addition, a number of advantages were observed, such as user-friendliness, cost-effectiveness, accuracy, precision and robustness., Conclusion: The stationary cuvette approach may be considered to be an appropriate alternative to derive analytical curves for analysing drug content in raw materials and medicines through UV-VIS spectrophotometry.