AARC Clinical Practice Guideline: Patient-Ventilator Assessment.

Given the important role of patient-ventilator assessments in ensuring the safety and efficacy of mechanical ventilation, a team of respiratory therapists and a librarian used Grading of Recommendations, Assessment, Development, and Evaluation methodology to make the following recommendations: (1) We recommend assessment of plateau pressure to ensure lung-protective ventilator settings (strong recommendation, high certainty); (2) We recommend an assessment of tidal volume (VT) to ensure lung-protective ventilation (4-8 mL/kg/predicted body weight) (strong recommendation, high certainty); (3) We recommend documenting VT as mL/kg predicted body weight (strong recommendation, high certainty); (4) We recommend an assessment of PEEP and auto-PEEP (strong recommendation, high certainty); (5) We suggest assessing driving pressure to prevent ventilator-induced injury (conditional recommendation, low certainty); (6) We suggest assessing FIO2 to ensure normoxemia (conditional recommendation, very low certainty); (7) We suggest telemonitoring to supplement direct bedside assessment in settings with limited resources (conditional recommendation, low certainty); (8) We suggest direct bedside assessment rather than telemonitoring when resources are adequate (conditional recommendation, low certainty); (9) We suggest assessing adequate humidification for patients receiving noninvasive ventilation (NIV) and invasive mechanical ventilation (conditional recommendation, very low certainty); (10) We suggest assessing the appropriateness of the humidification device during NIV and invasive mechanical ventilation (conditional recommendation, low certainty); (11) We recommend that the skin surrounding artificial airways and NIV interfaces be assessed (strong recommendation, high certainty); (12) We suggest assessing the dressing used for tracheostomy tubes and NIV interfaces (conditional recommendation, low certainty); (13) We recommend assessing the pressure inside the cuff of artificial airways using a manometer (strong recommendation, high certainty); (14) We recommend that continuous cuff pressure assessment should not be implemented to decrease the risk of ventilator-associated pneumonia (strong recommendation, high certainty); and (15) We suggest assessing the proper placement and securement of artificial airways (conditional recommendation, very low certainty).

Characterising applied forces during positive pressure ventilation: a randomised cross-over simulation study.

OBJECTIVE: To characterise applied force on the face and head during simulated mask ventilation with varying mask, device and expertise level. DESIGN: Randomised cross-over simulation study. SETTING: A quiet, empty room in the children's hospital. PARTICIPANTS: Neonatal healthcare providers, categorised as novices and experts in positive pressure ventilation (PPV). INTERVENTIONS: PPV for 2 min each in a 2×2 within-subjects design with two masks (round and anatomic) and two ventilation devices (T-piece and self-inflating bag (SIB)). MAIN OUTCOME MEASURES: Applied force (Newton (N)) measured under the head and at four locations on the manikin's face (nasal bridge, mentum, left and right zygomatic arches) and symmetry of force applied around the mask rim. RESULTS: For the 51 participants, force applied to the head was greater with the SIB than the T-piece (mean (SD): 16.03 (6.96) N vs 14.31 (5.16) N) and greater with the anatomic mask than the round mask (mean (SD): 16.07 (6.80) N vs 14.26 (5.35) N). Underhead force decreased over the duration of PPV for all conditions. Force measured on the face was greatest at the left zygomatic arch (median (IQR): 0.97 (0.70-1.43) N) and least at the mentum (median (IQR): 0.44 (0.28-0.61) N). Overall, experts applied more equal force around the mask rim compared with novices (median (IQR): 0.46 (0.26-0.79) N vs 0.65 (0.24-1.18) N, p<0.001). CONCLUSION: We characterised an initial dataset of applied forces on the face and head during simulated PPV and described differences in force when considering mask type, device type and expertise.

Quantitative Comparison of Ventilation Parameters of Different Approaches to Ventilator Splitting and Multiplexing.

CONTEXT: Amid the COVID-19 pandemic, this study delves into ventilator shortages, exploring simple split ventilation (SSV), simple differential ventilation (SDV), and differential multiventilation (DMV). The knowledge gap centers on understanding their performance and safety implications. HYPOTHESIS: Our hypothesis posits that SSV, SDV, and DMV offer solutions to the ventilator crisis. Rigorous testing was anticipated to unveil advantages and limitations, aiding the development of effective ventilation approaches. METHODS AND MODELS: Using a specialized test bed, SSV, SDV, and DMV were compared. Simulated lungs in a controlled setting facilitated measurements with sensors. Statistical analysis honed in on parameters like peak inspiratory pressure (PIP) and positive end-expiratory pressure. RESULTS: Setting target PIP at 15 cm H2O for lung 1 and 12.5 cm H2O for lung 2, SSV revealed a PIP of 15.67 ± 0.2 cm H2O for both lungs, with tidal volume (Vt) at 152.9 ± 9 mL. In SDV, lung 1 had a PIP of 25.69 ± 0.2 cm H2O, lung 2 at 24.73 ± 0.2 cm H2O, and Vts of 464.3 ± 0.9 mL and 453.1 ± 10 mL, respectively. DMV trials showed lung 1's PIP at 13.97 ± 0.06 cm H2O, lung 2 at 12.30 ± 0.04 cm H2O, with Vts of 125.8 ± 0.004 mL and 104.4 ± 0.003 mL, respectively. INTERPRETATION AND CONCLUSIONS: This study enriches understanding of ventilator sharing strategy, emphasizing the need for careful selection. DMV, offering individualization while maintaining circuit continuity, stands out. Findings lay the foundation for robust multiplexing strategies, enhancing ventilator management in crises.

[The Myth about the Laryngeal Mask]. / Der Mythos um die Larynxmaske.

Peak pressures ≥ 20 mbar are not a contraindication for laryngeal masks. The oropharyngeal leak pressure of a laryngeal mask does not correspond to the pressure at which oesophagogastric air leakage occurs. Setting a peak pressure limit of 20 cm H2O on the respirator can lead to critical situations because the tidal volume may then remain too low. A good alternative is to use a pressure alarm limit. The use of laryngeal masks does not preclude the use of PEEP and/or relaxation.

Pressure Support Ventilation Versus T-piece as Spontaneous Breathing Trials for Extubation of Patients with Chronic Obstructive Pulmonary Disease: A Systematic Review and Meta-analysis of Randomized Controlled Trials.

BACKGROUND: Weaning patients with COPD from mechanical ventilation (MV) presents a challenge, as literature on this topic is limited. This study compares PSV and T-piece during spontaneous breathing trials (SBT) in this specific population. METHODS: A search of PubMed, EMBASE, and Cochrane in September 2023 yielded four randomized controlled trials (RCTs) encompassing 560 patients. Among these, 287 (51%) used T-piece during SBTs. RESULTS: The PSV group demonstrated a significant improvement in the successful extubation rate compared to the T-piece (risk ratio [RR] 1.14; 95% confidence interval [CI] 1.03-1.26; p = 0.02). Otherwise, there was no statistically significant difference in the reintubation (RR 1.07; 95% CI 0.79-1.45; p = 0.67) or the ICU mortality rates (RR 0.99; 95% CI 0.63-1.55; p = 0.95). CONCLUSION: Although PSV in SBTs exhibits superior extubation success, consistent weaning protocols warrant further exploration through additional studies.

Short-term effects of positive expiratory pressure mask on ventilation inhomogeneity in children with cystic fibrosis: A randomized, sham-controlled crossover study.

BACKGROUND: Can physiotherapy with a positive expiratory pressure (PEP) mask improve peripheral ventilation inhomogeneity, a typical feature of children with cystic fibrosis (cwCF)? To answer this question, we used the nitrogen multiple-breath washout (N2MBW) test to measure diffusion-convection-dependent inhomogeneity arising within the intracinar compartment (Sacin*VT). METHODS: For this randomized, sham-controlled crossover trial, two N2MBW tests were performed near the hospital discharge date: one before and the other after PEP mask therapy (1 min of breathing through a flow-dependent PEP device attached to a face mask, followed by three huffs and one cough repeated 10 times) by either a standard (10-15 cmH20) or a sham (<5 cmH20) procedure on two consecutive mornings. Deception entailed misinforming the subjects about the nature of the study; also the N2MBW operators were blinded to treatment allocation. Study outcomes were assessed with mixed-effect models. RESULTS: The study sample was 19 cwCF (ten girls), aged 11.4 (2.7) years. The adjusted Sacin*VT mean difference between the standard and the sham procedure was -0.015 (90% confidence interval [CI]: -∞ to 0.025) L-1. There was no statistically significant difference in Scond*VT and lung clearance index between the two procedures: -0.005 (95% CI: -0.019 to 0.01) L-1 and 0.49 (95% CI: -0.05 to 1.03) turnovers, respectively. CONCLUSION: Our findings do not support evidence for an immediate effect of PEP mask physiotherapy on Sacin*VT with pressure range 10-15 cmH20. Measurement with the N2MBW and the crossover design were found to be time-consuming and unsuitable for a short-term study of airway clearance techniques.

Randomised study of a new inline respiratory function monitor (Juno) to improve mask seal and delivered ventilation with neonatal manikins.

BACKGROUND: Respiratory function monitors (RFMs) have been used extensively in manikin and infant studies yet have not become the standard of training. We report the outcomes of a new portable, lightweight RFM, the Juno, designed to show mask leak and deflation tidal volume to assist in positive pressure ventilation (PPV) competency training using manikins. METHODS: Two leak-free manikins (preterm and term) were used. Participants provided PPV to manikins using two randomised devices, self-inflating bag (SIB) and T-piece resuscitator (TPR), with Juno display initially blinded then unblinded in four 90 s paired sequences, aiming for adequate chest wall rise and target minimal mask leak with appropriate target delivered volume when using the monitor. RESULTS: 49 experienced neonatal staff delivered 15 569 inflations to the term manikin and 14 580 inflations to the preterm. Comparing blinded to unblinded RFM display, there were significant reductions in all groups in the number of inflations out of target range volumes (preterm: SIB 22.6-6.6%, TPR 7.1-4.2% and term: SIB 54.8-37.8%, TPR 67.2-63.8%). The percentage of mask leak inflations >60% was reduced in preterm: SIB 20.7-7.2%, TPR 23.4-7.4% and in term: SIB 8.7-3.6%, TPR 23.5-6.2%). CONCLUSIONS: Using the Juno monitor during simulated resuscitation significantly improved mask leak and delivered ventilation among otherwise experienced staff using preterm and term manikins. The Juno is a novel RFM that may assist in teaching and self-assessment of resuscitation PPV technique.

Rescue nasopharyngeal tube for preterm infants non-responsive to initial ventilation after birth.

BACKGROUND: Physiological changes during the insertion of a rescue nasopharyngeal tube (NPT) after birth are unclear. METHODS: Observational study of very preterm infants in the delivery room. Data were extracted at predefined timepoints starting with first facemask placement after birth until 5 min after insertion of NPT. End-expiratory lung impedance (EELI), heart rate (HR) and SpO2/FiO2-ratio were analysed over time. Changes during the same time span of NIPPV via facemask and NIPPV via NPT were compared. RESULTS: Overall, 1154 inflations in 15 infants were analysed. After NPT insertion, EELI increased significantly [0.33 AU/kg (0.19-0.57), p < 0.001]. Compared with the mask period, changes in EELI were not significantly larger during the NPT period [median difference (IQR) = 0.14 AU/kg (-0.14-0.53); p = 0.12]. Insertion of the NPT was associated with significant improvement in HR [52 (33-96); p = 0.001] and SpO2/FiO2-ratio [161 (69-169); p < 0.001] not observed during the mask period. CONCLUSIONS: In very preterm infants non-responsive to initial facemask ventilation after birth, insertion of an NPT resulted in a considerable increase in EELI. This additional gain in lung volume was associated with an immediate improvement in clinical parameters. The use of a NPT may prevent intubation in selected non-responsive infants. IMPACT: After birth, a nasopharyngeal tube may be considered as a rescue airway in newborn infants non-responsive to initial positive pressure ventilation via facemask. Although it is widely used among clinicians, its effect on lung volumes and physiological parameters remains unclear. Insertion of a rescue NPT resulted in a considerable increase in lung volume but this was not significantly larger than during facemask ventilation. However, insertion of a rescue NPT was associated with a significant and clinically important improvement in heart rate and oxygenation. This study highlights the importance of individual strategies in preterm resuscitation and introduces the NPT as a valid option.

Efficacy of an oscillating positive expiratory pressure device in patients with Mycobacterium avium complex pulmonary disease.

Patients with Mycobacterium avium complex pulmonary disease (MAC-PD) often suffer from chronic symptoms such as sputum production, which reduces quality of life. Oscillatory positive expiratory pressure (OPEP) devices are used in physiotherapy to promote the clearance of respiratory secretions. We report two cases of improved lung function and improved scores on the Leicester Cough Questionnaire (LCQ) and the Breathlessness, Cough and Sputum Scale (BCSS) after the use of OPEP in patients with MAC-PD where treatment with guideline-based therapy, including amikacin liposome inhalation suspension, had proved ineffective for symptoms. Use of OPEP might maximize the efficacy of therapy and thereby improves outcomes in patients with MAC-PD. It is important to use both guideline-based therapy and OPEP, especially in patients whose health-related quality of life is affected by sputum symptoms. Further prospective studies are warranted to assess the benefit of adding OPEP to guidelines concerning therapy for patients with MAC-PD and sputum symptoms.

Residual upper airway obstruction during nocturnal noninvasive ventilation despite high positive expiratory pressure. Impact of oronasal mask to nasal mask switch.

BACKGROUND: Nasal mask (NM) and oronasal masks (OM) can be used to provide noninvasive ventilation (NIV). Recent studies suggested that OM is the most used interface and that there is no difference in efficacy or in tolerance between OM and NM for chronic use. However, studies focusing on video laryngoscopy underlined the impact of OM in residual upper airway obstruction (UAO) under NIV. We sought to assess the real-life practice of switching from OM to NM when UAO events persist despite high EPAP levels. METHODS: In an open-label single center prospective cohort study, data from files and full night polysomnography on NM and OM were collected for patients wearing OM and presenting an UAO index ≥15/h despite an EPAP level ≥ 10 cmH20. RESULTS: Forty-four patients were included in the study. In 31 patients (74 %), switching to a NM reduced UAOi to ≥10/h. Interestingly, 92 % of these patients still had NM at 3 to 12 months of follow-up. Switching to a NM was also associated with a trend in paCO2 reduction and significant improvements in Epworth, sleep quality and NIV compliance. Successful interface switching was significantly associated with female gender, and a trend was observed in non-smokers. CONCLUSION: As for CPAP, switching to a NM improved NIV efficacy in a selected group of patients presenting residual UAO events despite high EPAP levels. Additionally, this switch has an impact on compliance and subjective sleepiness. Thus, in patients with persisting UAO on OM, switching to a NM could be a first-line intervention before considering further investigation such as polygraphy or video laryngoscopy. We also derive an algorithm for mask allocation and adaptation in acute and chronic NIV use.

Physiologic Effects of Reconnection to the Ventilator for 1 Hour Following a Successful Spontaneous Breathing Trial.

BACKGROUND: Reconnection to the ventilator for 1 h following a successful spontaneous breathing trial (SBT) may reduce reintubation rates compared with direct extubation. However, the physiologic mechanisms leading to this effect are unclear. RESEARCH QUESTION: Does reconnection to the ventilator for 1 h reverse alveolar derecruitment induced by SBT, and is alveolar derecruitment more pronounced with a T-piece than with pressure-support ventilation (PSV)? STUDY DESIGN AND METHODS: This is an ancillary study of a randomized clinical trial comparing SBT performed with a T-piece or with PSV. Alveolar recruitment was assessed by using measurement of end-expiratory lung volume (EELV). RESULTS: Of the 25 patients analyzed following successful SBT, 11 underwent SBT with a T-piece and 14 with PSV. At the end of the SBT, EELV decreased by -30% (95% CI, -37 to -23) compared with baseline prior to the SBT. This reduction was greater with a T-piece than with PSV: -43% (95% CI, -51 to -35) vs -20% (95% CI, -26 to -13); P < .001. Following reconnection to the ventilator for 1 h, EELV accounted for 96% (95% CI, 92 to 101) of baseline EELV and did not significantly differ from prior to the SBT (P = .104). Following 10 min of reconnection to the ventilator, EELV wasted at the end of the SBT was completely recovered using PSV (P = .574), whereas it remained lower than prior to the SBT using a T-piece (P = .010). INTERPRETATION: Significant alveolar derecruitment was observed at the end of an SBT and was markedly more pronounced with a T-piece than with PSV. Reconnection to the ventilator for 1 h allowed complete recovery of alveolar derecruitment. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov; No.: NCT04227639; URL: www. CLINICALTRIALS: gov.

Spontaneous-Breathing Trials with Pressure-Support Ventilation or a T-Piece.

BACKGROUND: Spontaneous-breathing trials can be performed with the use of either pressure-support ventilation (PSV) or a T-piece. Whether PSV trials may result in a shorter time to tracheal extubation than T-piece trials, without resulting in a higher risk of reintubation, among patients who have a high risk of extubation failure is unknown. METHODS: In this multicenter, open-label trial, we randomly assigned patients who had a high risk of extubation failure (i.e., were >65 years of age or had an underlying chronic cardiac or respiratory disease) to undergo spontaneous-breathing trials performed with the use of either PSV (with a pressure-support level of 8 cm of water and no positive end-expiratory pressure) or a T-piece. The primary outcome was the total time without exposure to invasive ventilation (reported as the number of ventilator-free days) at day 28 after the initial spontaneous-breathing trial. Secondary outcomes included extubation within 24 hours and extubation within 7 days after the initial spontaneous-breathing trial, as well as reintubation within 7 days after extubation. RESULTS: A total of 969 patients (484 in the PSV group and 485 in the T-piece group) were included in the analysis. At day 28, the median number of ventilator-free days was 27 (interquartile range, 24 to 27) in the PSV group and 27 (interquartile range, 23 to 27) in the T-piece group (difference, 0 days; 95% confidence interval [CI], -0.5 to 1; P = 0.31). Extubation was performed within 24 hours in 376 patients (77.7%) in the PSV group and in 350 patients (72.2%) in the T-piece group (difference, 5.5 percentage points; 95% CI, 0.01 to 10.9), and extubation was performed within 7 days in 473 patients (97.7%) and 458 patients (94.4%), respectively (difference, 3.3 percentage points; 95% CI, 0.8 to 5.9). Reintubation was performed in 72 of 481 patients (14.9%) in the PSV group and in 65 of 477 patients (13.6%) in the T-piece group (difference, 1.3 percentage points; 95% CI, -3.1 to 5.8). Cardiac or respiratory arrest was a reason for reintubation in 9 patients (3 in the PSV group and 6 in the T-piece group). CONCLUSIONS: Among patients who had a high risk of extubation failure, spontaneous-breathing trials performed with PSV did not result in significantly more ventilator-free days at day 28 than spontaneous-breathing trials performed with a T-piece. (Supported by the French Ministry of Health; TIP-EX ClinicalTrials.gov number, NCT04227639.).

Early individualized positive end-expiratory pressure guided by electrical impedance tomography in acute respiratory distress syndrome: a randomized controlled clinical trial.

BACKGROUND: Individualized positive end-expiratory pressure (PEEP) by electrical impedance tomography (EIT) has potential interest in the optimization of ventilation distribution in acute respiratory distress syndrome (ARDS). The aim of the study was to determine whether early individualized titration of PEEP with EIT improved outcomes in patients with ARDS. METHODS: A total of 117 ARDS patients receiving mechanical ventilation were randomly assigned to EIT group (n = 61, PEEP adjusted based on ventilation distribution) or control group (n = 56, low PEEP/FiO2 table). The primary outcome was 28-day mortality. Secondary and exploratory outcomes were ventilator-free days, length of ICU stay, incidence of pneumothorax and barotrauma, and difference in Sequential Organ Failure Assessment (SOFA) score at day 1 (ΔD1-SOFA) and day 2 (ΔD2-SOFA) compared with baseline. MEASUREMENTS AND MAIN RESULTS: There was no statistical difference in the value of PEEP between the EIT group and control group, but the combination of PEEP and FiO2 was different between groups. In the control group, a significantly positive correlation was found between the PEEP value and the corresponding FiO2 (r = 0.47, p < 0.00001) since a given matched table was used for PEEP settings. Diverse combinations of PEEP and FiO2 were found in the EIT group (r = 0.05, p = 0.68). There was no significant difference in mortality rate (21% vs. 27%, EIT vs. control, p = 0.63), ICU length of stay (13.0 (7.0, 25.0) vs 10.0 (7.0, 14.8), median (25th-75th percentile); p = 0.17), and ventilator-free days at day 28 (14.0 (2.0, 23.0) vs 19.0 (0.0, 24.0), p = 0.55) between the two groups. The incidence of new barotrauma was zero. Compared with control group, significantly lower ΔD1-SOFA and ΔD2-SOFA were found in the EIT group (p < 0.001) in a post hoc comparison. Moreover, the EIT group exhibited a significant decrease of SOFA at day 2 compared with baseline (paired t-test, difference by - 1 (- 3.5, 0), p = 0.001). However, the control group did show a similar decrease (difference by 1 (- 2, 2), p = 0.131). CONCLUSION: Our study showed a 6% absolute decrease in mortality in the EIT group: a statistically non-significant, but clinically non-negligible result. This result along with the showed improvement in organ function might justify further reserach to validate the beneficial effect of individualized EIT-guided PEEP setting on clinical outcomes of patients with ARDS. TRIAL REGISTRATION: ClinicalTrials, NCT02361398. Registered 11 February 2015-prospectively registered, https://clinicaltrials.gov/show/NCT02361398 .

Devices for Administering Ventilation at Birth: A Systematic Review.

CONTEXT: Positive pressure ventilation (PPV) is the most important intervention during neonatal resuscitation. OBJECTIVE: To compare T-piece resuscitators (TPRs), self-inflating bags (SIBs), and flow-inflating bags for newborns receiving PPV during delivery room resuscitation. DATA SOURCES: Medline, Embase, Cumulative Index to Nursing and Allied Health Literature, Cochrane Database of Systematic Reviews, and trial registries (inception to December 2020). STUDY SELECTION: Randomized, quasi-randomized, interrupted time series, controlled before-and-after, and cohort studies were included without language restrictions. DATA EXTRACTION: Two researchers independently extracted data, assessed the risk of bias, and evaluated the certainty of evidence. The primary outcome was in-hospital mortality. When appropriate, data were pooled by using fixed-effect models. RESULTS: Meta-analysis of 4 randomized controlled trials (1247 patients) revealed no significant difference between TPR and SIB for in-hospital mortality (risk ratio 0.74; 95% confidence interval [CI] 0.40 to 1.34). Resuscitation with a TPR resulted in a shorter duration of PPV (mean difference -19.8 seconds; 95% CI -27.7 to -12.0 seconds) and lower risk of bronchopulmonary dysplasia (risk ratio 0.64; 95% CI 0.43 to 0.95; number needed to treat 32). No differences in clinically relevant outcomes were found in 2 randomized controlled trials used to compare SIBs with and without positive end-expiratory pressure valves. No studies used to evaluate flow-inflating bags were found. LIMITATIONS: Certainty of evidence was very low or low for most outcomes. CONCLUSIONS: Resuscitation with a TPR compared with an SIB reduces the duration of PPV and risk of bronchopulmonary dysplasia. A strong recommendation cannot be made because of the low certainty of evidence. There is insufficient evidence to determine the effectiveness of positive end-expiratory pressure valves when used with SIBs.

Performance characteristics of high-frequency percussive ventilation under hyperbaric conditions.

Introduction: Safe administration of critical care hyperbaric medicine requires specialized equipment and advanced training. Equipment must be tested in order to evaluate function in the hyperbaric environment. High-frequency percussive ventilation (HFPV) has been used in intensive care settings effectively, but it has never been tested in a hyperbaric chamber. Methods: Following a modified U.S. Navy testing protocol used to evaluate hyperbaric ventilators, we evaluated an HFPV transport ventilator in a multiplace hyperbaric chamber at 1.0, 1.9, and 2.8 atmospheres absolute (ATA). We used a test lung with analytical software for data collection. The ventilator uses simultaneous cyclic pressure-controlled ventilation at a pulsatile flow rate (PFR)/oscillatory continuous positive airway pressure (oCPAP) ratio of 30/10 with a high-frequency oscillation percussive rate of 500 beats per minute. Inspiratory and expiratory times were maintained at two seconds throughout each breathing cycle. Results: During manned studies, the PFR/oCPAP ratios were 26/6, 22/7, and 22.5/8 at an airway resistance of 20cm H2O/L/second and 18/9, 15.2/8.5, and 13.6/7 at an airway resistance of 50 cm/H2O/L/second at 1, 1.9, and 2.8 ATA. The resulting release volumes were 800, 547, and 513 mL at airway resistance of 20 cm H2O/L/sec and 400, 253, and 180 mL at airway resistance of 50 cm/H2O/L/sec at 1, 1.9, and 2.8 ATA. Unmanned testing showed similar changes. The mean airway pressure (MAP) remained stable throughout all test conditions; theoretically, supporting adequate lung recruitment and gas exchange. A case where HFPV was used to treat a patient for CO poisoning was presented to illustrate that HFPV worked well under HBO2 conditions and no complications occurred during HBO2 treatment. Conclusion: The HFPV transport ventilator performed adequately under hyperbaric conditions and should be considered a viable option for hyperbaric critical care. This ventilator has atypical terminology and produces unique pulmonary physiology, thus requiring specialized training prior to use.

Neonatal resuscitation: EN-BIRTH multi-country validation study.

BACKGROUND: Annually, 14 million newborns require stimulation to initiate breathing at birth and 6 million require bag-mask-ventilation (BMV). Many countries have invested in facility-based neonatal resuscitation equipment and training. However, there is no consistent tracking for neonatal resuscitation coverage. METHODS: The EN-BIRTH study, in five hospitals in Bangladesh, Nepal, and Tanzania (2017-2018), collected time-stamped data for care around birth, including neonatal resuscitation. Researchers surveyed women and extracted data from routine labour ward registers. To assess accuracy, we compared gold standard observed coverage to survey-reported and register-recorded coverage, using absolute difference, validity ratios, and individual-level validation metrics (sensitivity, specificity, percent agreement). We analysed two resuscitation numerators (stimulation, BMV) and three denominators (live births and fresh stillbirths, non-crying, non-breathing). We also examined timeliness of BMV. Qualitative data were collected from health workers and data collectors regarding barriers and enablers to routine recording of resuscitation. RESULTS: Among 22,752 observed births, 5330 (23.4%) babies did not cry and 3860 (17.0%) did not breathe in the first minute after birth. 16.2% (n = 3688) of babies were stimulated and 4.4% (n = 998) received BMV. Survey-report underestimated coverage of stimulation and BMV. Four of five labour ward registers captured resuscitation numerators. Stimulation had variable accuracy (sensitivity 7.5-40.8%, specificity 66.8-99.5%), BMV accuracy was higher (sensitivity 12.4-48.4%, specificity > 93%), with small absolute differences between observed and recorded BMV. Accuracy did not vary by denominator option. < 1% of BMV was initiated within 1 min of birth. Enablers to register recording included training and data use while barriers included register design, documentation burden, and time pressure. CONCLUSIONS: Population-based surveys are unlikely to be useful for measuring resuscitation coverage given low validity of exit-survey report. Routine labour ward registers have potential to accurately capture BMV as the numerator. Measuring the true denominator for clinical need is complex; newborns may require BMV if breathing ineffectively or experiencing apnoea after initial drying/stimulation or subsequently at any time. Further denominator research is required to evaluate non-crying as a potential alternative in the context of respectful care. Measuring quality gaps, notably timely provision of resuscitation, is crucial for programme improvement and impact, but unlikely to be feasible in routine systems, requiring audits and special studies.

Comparison of an expiratory flow accelerator device versus positive expiratory pressure for tracheobronchial airway clearance after lung cancer lobectomy: a preliminary study.

OBJECTIVE: A new type of device has recently been introduced in chest physiotherapy as an aid to tracheo-bronchial airway clearance: expiratory flow accelerator (EFA). It promotes mucus clearance without generating any pressure gradient, allowing patients to breathe at tidal volume against no resistance. DESIGN: Pilot randomized controlled study. SETTING: Tertiary hospital. PARTICIPANTS: Fifty adult patients who underwent lung cancer lobectomy were randomized to undergo chest physiotherapy with EFA (n=26) or PEP (n=24). INTERVENTIONS: EFA; PEP bottle. MAIN OUTCOMES: Incidence of postoperative pulmonary complications (PPC) and length of stay. SECONDARY OUTCOMES: trends in inspiratory capacity, respiratory rate, oxygen saturation, and dyspnoea. Patients rated user-friendliness of the two devices on a 5-point Likert scale. RESULTS: A slightly different incidence of PPCs was observed between the EFA and PEP group. Nevertheless, the length of stay was similar in the two groups. No substantial differences were seen in trends of inspiratory capacity, respiratory rate, oxygen saturation, dyspnoea between the two groups. Patient-reported user-friendliness of the two devices did not differ significantly, although the use of the EFA device appeared less strenuous. CONCLUSIONS: Results of this pilot study point to the use of EFA as an alternative treatment option rather than as a replacement for the PEP bottle in chest physiotherapy following lung cancer lobectomy. EFA may be preferable for weaker patients and/or with airway leakages in whom PEP has limited indications. Further investigation in a larger sample is required to statistically confirm the findings. Clinical Trial Registration Number ChiCTR-ONC-17013255.