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Aim: Review changes in neonatal ventilation practice within our regional transport service, Embrace, identifying interventions with greatest impact on improved rates of normocapnia during transfer., Methods: Using internal transport databases and UK Neonatal Transport Group data submissions, we tracked local and national rates of ventilation and normocapnia. We correlated this with internal changes in practice, including introduction of new equipment, staffing changes, educational interventions and quality improvement projects., Results: Data demonstrated improvement in normocapnia rates benchmarked against national figures, which was not explained by changes in ventilation methods or rates, or by changes in availability of post-transfer gases. Greatest improvement was identified following introduction of transcutaneous CO 2 monitoring and ventilators enabling volume-guided ventilation strategies. Additionally, although less quantifiable, educational and quality improvement interventions, and case review mechanisms were felt to be influential., Conclusion: Volume guided ventilation and transcutaneous CO 2 monitoring have had a positive influence on the maintenance of normocapnia during transfer at Embrace Transport Service, although introduction of new equipment still presents challenges which must be overcome. Recognising the significant impact of these technologies allows for ongoing financial, time and educational investment to emphasise their importance and ensure appropriate awareness of limitations and troubleshooting options, maximising their positive impact., (© 2023 Foundation Acta Paediatrica. Published by John Wiley & Sons Ltd.)

Background: Lung volume loss is a major risk factor for postoperative respiratory complications after general anaesthesia and mechanical ventilation. We hypothesise that spontaneous breathing without pressure support may enhance the risk for atelectasis development. Therefore, we aimed at characterising whether pressure support prevents changes in lung function in patients breathing spontaneously through laryngeal mask airway., Methods: In this randomised controlled trial, adult female patients scheduled for elective gynaecological surgery in lithotomy position were randomly assigned to the continuous spontaneous breathing group (CSB, n = 20) or to the pressure support ventilation group (PSV, n = 20) in a tertiary university hospital. Lung function measurements were carried out before anaesthesia and 1 h postoperatively by a researcher blinded to the group allocation. Lung clearance index calculated from end-expiratory lung volume turnovers as primary outcome variable was assessed by the multiple-breath nitrogen washout technique (MBW). Respiratory mechanics were measured by forced oscillations to assess parameters reflecting the small airway function and respiratory tissue stiffness., Results: MBW was successfully completed in 18 patients in both CSB and PSV groups. The decrease in end-expiratory lung volume was more pronounced in the CSB than that in the PSV group (16.6 ± 6.6 [95% CI] % vs. 7.6 ± 11.1%, p = .0259), with no significant difference in the relative changes of the lung clearance index (-0.035 ± 7.1% vs. -0.18 ± 6.6%, p = .963). The postoperative changes in small airway function and respiratory tissue stiffness were significantly lower in the PSV than in the CSB group (p < .05 for both)., Conclusions: These results suggest that pressure support ventilation protects against postoperative lung-volume loss without affecting ventilation inhomogeneity in spontaneously breathing patients with increased risk for atelectasis development., Trial Registration: NCT02986269., (© 2023 The Acta Anaesthesiologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.)

Background: Spontaneous breathing is desirable in most ventilated patients. We therefore studied the influence of isoflurane versus propofol sedation on early spontaneous breathing in ventilated surgical intensive care patients and evaluated potential mediation by opioids and arterial carbon dioxide during the first 20 h of study sedation., Methods: We included a single-center subgroup of 66 patients, who participated in a large multi-center trial assessing efficacy and safety of isoflurane sedation, with 33 patients each randomized to isoflurane or propofol sedation. Both sedatives were titrated to a sedation depth of -4 to -1 on the Richmond Agitation Sedation Scale. The primary outcome was the fraction of time during which patients breathed spontaneously., Results: Baseline characteristics of isoflurane and propofol-sedated patients were well balanced. There were no substantive differences in management or treatment aside from sedation, and isoflurane and propofol provided nearly identical sedation depths. The mean fraction of time spent spontaneously breathing was 82% [95% CI: 69, 90] in patients sedated with isoflurane compared to 35% [95% CI: 22, 51] in those assigned to propofol: median difference: 61% [95% CI: 14, 89], p < .001. After adjustments for sufentanil dose and arterial carbon dioxide partial pressure, patients sedated with isoflurane were twice as likely to breathe spontaneously than those sedated with propofol: adjusted risk ratio: 2.2 [95%CI: 1.4, 3.3], p < .001., Conclusions: Isoflurane compared to propofol sedation promotes early spontaneous breathing in deeply sedated ventilated intensive care patients. The benefit appears to be a direct effect isoflurane rather than being mediated by opioids or arterial carbon dioxide., (© 2021 The Authors. Acta Anaesthesiologica Scandinavica published by John Wiley & Sons Ltd on behalf of Acta Anaesthesiologica Scandinavica Foundation.)

New Findings: What is the central question of the study? Does respiratory support ensure blood gas homeostasis and the relevance of experimental outcomes? What is the main finding and its importance? Spontaneous breathing during surgical intervention under anaesthesia results in impaired gas exchange and loss of diaphragm muscle strength in rats. Subsequent short-term mechanical ventilation restored blood gas homeostasis and diaphragm muscle strength. Blood gas homeostasis interferes substantially with experimental conditions and may alter study results. Monitoring and maintenance of blood gas balance is required to ensure quality and relevance of physiological animal experiments., Abstract: In pre-clinical small animal studies with surgical interventions under general anaesthesia, animals are often left to breathe spontaneously. However, anaesthesia may impair respiratory functions and result in disturbed blood gas homeostasis. In turn, the disturbed blood gas homeostasis can affect physiological functions and thus unintentionally impact the experimental results. We hypothesized that short-term mechanical ventilation restores blood gas balance and physiological functions despite anaesthesia and surgical interventions. Therefore, we investigated variables of blood gas analyses and diaphragm muscle strength in rats anaesthetized with ketamine/medetomidine after tracheotomy and catheterization of the carotid artery under spontaneous breathing and after 20 min of mechanical ventilation following the same surgical intervention. Spontaneous breathing during general anaesthesia and surgical intervention resulted in unphysiological blood oxygen partial pressure (<65 mmHg) and carbon dioxide partial pressure (>55 mmHg). After subsequent short-term mechanical ventilation, blood gas partial pressures were restored to their physiological ranges. Additionally, diaphragm muscle strength of animals breathing spontaneously was lower compared to animals that received subsequent mechanical ventilation (P = 0.0063). We conclude that spontaneous breathing of rats under ketamine/medetomidine anaesthesia is not sufficient to maintain a physiological blood gas balance. Disturbed blood gas balance is related to reduced diaphragm muscle strength. Mechanical ventilation for only 20 min restores blood gas homeostasis and muscle strength. Therefore, monitoring and maintenance of blood gas balance should be conducted to ensure quality and relevance of small animal experiments., (© 2020 The Authors. Experimental Physiology published by John Wiley & Sons Ltd on behalf of The Physiological Society.)

Background: In caring for mechanically ventilated adults with acute respiratory distress syndrome (ARDS), clinicians are faced with an uncertain choice between controlled or spontaneous breathing modes. Observational data indicate considerable practice variation which may be driven by differences in sedation and mobilisation practices. The benefits and harms of either strategy are largely unknown., Methods: A scoping review will be prepared according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) extension for scoping reviews. We will review the clinical literature on controlled vs spontaneous breathing in mechanically ventilated patients with ARDS of any severity. Studies reporting on qualitative and/or quantitative data from any world region will be considered. For inclusion, studies must include data on mechanically ventilated patients with ARDS who are allowed spontaneous (triggered ventilation). Searches will be conducted in four electronic databases without any limitation on publication date and language. We will assess the quality of evidence according to the Grading of Recommendations Assessment, Development and Evaluation (GRADE) methodology, where appropriate., Conclusion: We will perform a scoping review of the clinical literature on controlled vs spontaneously breathing in mechanically ventilated patients who fulfil ARDS criteria (including acute lung injury). This is to elucidate if a pragmatic clinical trial comparing controlled and spontaneous mechanical ventilation is warranted and will allow us to formulate relevant research questions., (© 2020 The Acta Anaesthesiologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.)

Background: Echocardiography was reported to be a good predictor of weaning failure when using T-piece method, but information about its efficacy in a pressure support setting is scarce. This study aimed to investigate the efficacy of echocardiography during spontaneous breathing trial with low-level pressure support for predicting weaning failure among medical critically ill patients., Methods: This prospective cohort study was conducted in adult respiratory failure patients that tolerated low pressure support weaning for 30 minutes. Echocardiogram was performed during pressure support ventilation before extubation. Weaning failure was defined as reintubation within 48 hours., Results: Of the 52 included patients (mean age 65.9 ± 17.8 years), 14 experienced weaning failure. Severe pneumonia, metabolic acidosis, and septic shock were the leading causes of respiratory failure. Univariate analysis identified BMI > 24, peak A wave < 100 cm/s, E/Ea > 14, and inferior vena cava maximum diameter (IVC max ) > 17 mm as factors associated with reintubation. Multivariate analysis revealed E/Ea > 14 and IVC max  > 17 mm to be independent predictors of weaning failure., Conclusion: Inferior vena cava maximum diameter > 17 and E/Ea ratio ≥ 14 independently predict weaning failure in patients with preserved left ventricular systolic function. This finding confirms that preload status of both ventricles plays a major role in weaning failure., (© 2019 Wiley Periodicals, Inc.)

Background: The study objective was to examine the correlation between regional ventilation distribution measured with electrical impedance tomography (EIT) and weaning outcomes during spontaneous breathing trial (SBT)., Methods: Fifteen patients received 100% automatic tube compensation (ATC) during the first and 70% during the second hour. Another 15 patients received external continuous positive airway pressure (CPAP) of 5 and 7.5 cmH 2 O during the first and second hours, respectively. Regional ventilation distributions were monitored with EIT., Results: Tidal volume and tidal variation of impedance correlated significantly during assist-control ventilation and ATC in all patients (r 2 = 0.80 ± 0.18, P < 0.001). Higher support levels resulted in similar ventilation distribution and tidal volume, but higher end-expiratory lung impedance (EELI) (P < 0.05). Analysis of regional intratidal gas distribution revealed a redistribution of ventilation towards dorsal regions with lower support level in 13 of 30 patients. These patients had a higher weaning success rate (only 1 of 13 patients failed). Eight of 17 other patient failed (P < 0.05). The number of SBT days needed for weaning was significantly lower in the former group of 13 patients (13.1 ± 4.0 vs. 20.9 ± 11.2 days, P < 0.05)., Conclusions: Regional ventilation distribution patterns during inspiration were associated with weaning outcomes, and they may be used to predict the success of extubation., (© 2017 The Acta Anaesthesiologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.)

Aim: Despite a recent increase in the use of ventilators in the home setting for children with chronic respiratory failure, there is currently no unified approach for clinical decision‐making for children requiring long‐term mechanical ventilation. The purpose of this study is to understand the clinician's perspective on decision‐making around home ventilation for children, and how home‐based care contributes to successful outcomes in this population. Methods: We recruited physicians and home ventilation nurses with at least 2 years' experience working in an Australian paediatric tertiary home ventilation service using professional networks and snowball sampling. Semi‐structured interviews were conducted by two researchers between February 2019 and June 2020. Interviews were audio‐recorded, transcribed, and analysed using inductive content analysis. Results: Twenty‐five individuals participated (17 physicians and 8 home ventilation nurses). Participants viewed themselves as impartial medical advocates in the decision‐making process, believing the decision to initiate or cease ventilation belonged to the child's family. While participants held the child's quality of life as the cornerstone of decision‐making, quality of life was subjective and family specific. Conclusion: These findings provide insight into how clinicians working with children with chronic respiratory insufficiency approach the decision to introduce home‐based ventilation. By understanding their role, strategies can be developed to assist them, leading to better outcomes for patients and families. Further research is needed to compare the perspectives of clinicians with the experience of ventilator‐assisted children and families in Australia. [ABSTRACT FROM AUTHOR]

Background The number of elderly in the general population is growing. There are therefore implications for the provision of intensive care unit (ICU) care to elderly patients. Aim Our aim was to determine the incidence of ICU invasive mechanical ventilation ( IMV), long-term outcomes of patients treated with IMV, and trends in these variables over a 10-year period in New Zealand, with a focus on very elderly patients (aged 80 years and over). Methods Analysis of New Zealand public hospital discharge data from July 1999 to June 2010, with linked long-term mortality data. Transfers or readmissions to different hospitals were linked using a national unique patient identifier. Results There were 58 003 patients treated with IMV in a New Zealand ICU. Of these patients, 6.6% were very elderly. Population rates of ICU IMV declined or were static over all age groups. The 2-year mortality rate ranged from 15% in patients aged 16-39 years to 52% in the very elderly. The 2-year mortality rates for the very elderly were highest for acute medical patients (78%), followed by acute surgical admissions (46%) and elective admissions (35%). The 2-year mortality rate for all patients declined over the study period, and declined or was static for all age groups and admission types. In the very elderly, the standardised mortality ratio of patients surviving at 1 year who survived their second year after admission, compared with the age-matched general population, was lower than all other age groups. Conclusion For very elderly patients over the period 1999-2009, the population rate of IMV was static and 2-year mortality declined. [ABSTRACT FROM AUTHOR]

Background Positive-pressure ventilation during transport of intubated patients is generally delivered via a hand-pressurized device. Of these devices, self-inflating resuscitators (SIR) and flow-inflating resuscitators (FIR) constitute the two major types used. Selection of a particular device for transport, however, remains largely an institutional practice. Objective To evaluate the hypothesis that transport ventilation goals of intubated pediatric patients are better achieved using an FIR compared to an SIR. Methods This randomized crossover simulation study compared the performance of SIR and FIR among anesthesia providers in a pediatric transport scenario. Subjects hand-ventilated a test lung while simultaneously maneuvering a stretcher bed to simulate patient transport. Hand ventilation was carried out using a Jackson-Rees circuit (FIR) and a Laerdal pediatric silicone resuscitator (SIR). The primary outcome was the proportion of total breaths delivered within the predefined target PIP/PEEP range (30+/− 3, 10+/− 3 cm H2O). Secondary outcomes included proportion of total breaths delivered with operationally defined unacceptable breath variables (PIP > 35 cm H2O or PEEP < 5 cm H2O). Results Overall, participants were four times more likely to deliver target breaths and one-third less likely to deliver unacceptable breaths using the FIR compared to the SIR. When comparing device performance, a 44% increase in the proportions of target breaths and a 40.4% decrease in unacceptable breaths using the FIR were observed ( P < 0.0001 for both). Conclusions Hand ventilation during patient transport is superior using the FIR compared to the SIR to achieve target ventilatory goals and avoid unacceptable ventilatory cycles. [ABSTRACT FROM AUTHOR]