Effects of patient positioning on respiratory mechanics in mechanically ventilated ICU patients

Management of pregnant women in tertiary maternity hospitals in the Paris area referred to the intensive care unit for acute hypoxaemic respiratory failure related to SARS-CoV-2: which practices for which outcomes?

BACKGROUND

Evidence for the management of pregnant women with acute hypoxaemic respiratory failure (AHRF) is currently lacking. The likelihood of avoiding intubation and the risks of continuing the pregnancy under invasive ventilation remain undetermined. We report the management and outcome of pregnant women with pneumonia related to SARS-CoV-2 admitted to the ICU of tertiary maternity hospitals of the Paris area.

METHODS

We studied a retrospective cohort of pregnant women admitted to 15 ICUs with AHRF related to SARS-CoV-2 defined by the need for O2 ≥ 6 L/min, high-flow nasal oxygen (HFNO), non-invasive or invasive ventilation. Trajectories were assessed to determine the need for intubation and the possibility of continuing the pregnancy on invasive ventilation.

RESULTS

One hundred and seven pregnant women, 34 (IQR: 30-38) years old, at a gestational age of 27 (IQR: 25-30) weeks were included. Obesity was present in 37/107. Intubation was required in 47/107 (44%). Intubation rate according to respiratory support was 14/19 (74%) for standard O2, 17/36 (47%) for non-invasive ventilation and 16/52 (31%) for HFNO. Factors significantly associated with intubation were pulmonary co-infection: adjusted OR: 3.38 (95% CI 1.31-9.21), HFNO: 0.11 (0.02-0.41) and non-invasive ventilation: 0.20 (0.04-0.80). Forty-six (43%) women were delivered during ICU stay, 39/46 (85%) for maternal pulmonary worsening, 41/46 (89%) at a preterm stage. Fourteen non-intubated women were delivered under regional anaesthesia; 9/14 ultimately required emergency intubation. Four different trajectories were identified: 19 women were delivered within 2 days after ICU admission while not intubated (12 required prolonged intubation), 23 women were delivered within 2 days after intubation, in 11 intubated women pregnancy was continued allowing delivery after ICU discharge in 8/11, 54 women were never intubated (53 were delivered after discharge). Timing of delivery after intubation was mainly dictated by gestational age. One maternal death and one foetal death were recorded.

CONCLUSION

In pregnant women with AHRF related to SARS-CoV-2, HFNO and non-invasive mechanical ventilation were associated with a reduced rate of intubation, while pulmonary co-infection was associated with an increased rate. Pregnancy was continued on invasive mechanical ventilation in one-third of intubated women. Study registration retrospectively registered in ClinicalTrials (NCT05193526).

Clinical application of intrapulmonary percussive ventilation: A scoping review

Impaired respiratory function secondary to acute or chronic respiratory disease poses a significant clinical and healthcare burden. Intrapulmonary percussive ventilation (IPV) is used in various clinical settings to treat excessive airway secretions, pulmonary atelectasis, and impaired gas exchange. Despite IPV's wide use, there is a lack of clinical guidance on IPV application which may lead to inconsistency in clinical practice. This scoping review aimed to summarise the clinical application methods and dosage of IPV used by clinicians and researchers to provide guidance. A two-staged systematic search was conducted to retrieve studies that used IPV in inpatient and outpatient settings. MEDLINE, EMBASE, CINAHL, Scopus, and Google scholar were searched from January 1979 till 2022. Studies with patients aged ≥16 years and published in any language were included. Two reviewers independently screened the title and abstract, reviewed full text articles, and extracted data. Search yielded 514 studies. After removing duplicates and irrelevant studies, 25 studies with 905 participants met the inclusion criteria. This is the first scoping review to summarise IPV application methods and dosages from the available studies in intensive care unit (ICU), acute inpatient (non-ICU), and outpatient settings. Some variations in clinical applications and prescribed dosages of IPV were noted. Despite variations, common trends in clinical application and prescription of IPV dosages were observed and summarised to assist clinicians with IPV intervention. Although an evidence-based clinical guideline could not be provided, this review provides detailed information on IPV application and dosages in order to provide clinical guidance and lays a foundation towards developing a clinical practice guideline in the future.

Enhancing Safety in Tumescent Liposuction: Managing Sedation-Related Respiratory Issues and Serious Complications Under Deep Sedation with the Propofol-Ketamine Protocol

BACKGROUND

Over the past 4 years, aesthetic surgery, notably liposuction, has substantially increased. Tumescent liposuction, a popular technique, has two variants-true tumescent liposuction (TTL) and semi-tumescent liposuction. While TTL reduces risks, it has limitations. There is no literature reported on semi-tumescent liposuction under deep sedation using the propofol-ketamine protocol, which is proposed as a potentially safe alternative.

METHODS

The retrospective analysis covered 8 years and included 3094 patients performed for tumescent liposuction under deep sedation, utilizing the propofol-ketamine protocol. The evaluation of patient safety involved an examination of potential adverse events with a specific focus on respiratory issues related to sedation, including instances of mask ventilation.

RESULTS

Among the 3094 cases, no fatalities were recorded. Noteworthy events included 43 mask ventilation instances, primarily occurring in the initial 10 min. Twelve cases experienced surgery cancellation due to various factors, including respiratory issues. Three patients were transferred to upper-level hospitals, while another three required blood transfusions. Vigilant management prevented significant complications, and other adverse events like venous thromboembolism (VTE), fat embolism, severe lidocaine toxicity, and so on were not observed.

CONCLUSIONS

The analysis of 3094 tumescent liposuction cases highlighted the overall safety profile of the propofol-ketamine protocol under deep sedation. The scarcity of severe complications underscores its viability. The study emphasizes the significance of thorough preoperative assessments, careful patient selection, and awareness of potential complications. Prompt interventions, particularly in addressing sedation-related respiratory issues, further contribute to positive outcomes for patients.

LEVEL OF EVIDENCE IV

This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Adaptation and clinical application of assistive device chair for bedside sitting in acute stroke phase: two case reports

PURPOSE

This report presents the adaptation of an assistive device chair for bedside sitting and its application in two patients with trunk control impairment in the acute stroke phase.

MATERIALS AND METHODS

The device was built with polyvinylchloride (PVC) pipes and designed by a team of mechanical engineers and physiotherapists to maintain a prolonged sitting position with less demand from therapists. To test the device, two patients were followed up during the acute phase of stroke. Both patients underwent an early mobilization program (30 min, twice a day, for three days) with an assistive device chair for bedside sitting. Patients were evaluated using the National Institutes of Health Stroke Scale (NIHSS), Trunk Impairment Scale (TIS), and International Classification of Functioning, Disability, and Health (ICF) checklist (b: body function; d: activity and participation).

RESULTS

The adaptations generated the following equipment: 1) foldable, 2) three levels of backrest inclination, and 3) a safety anterior support or an activity table. Both patients showed clinical improvement after the intervention period, with NIHSS score reduction, TIS improvement, and greater functionality and independence on the ICF framework.

CONCLUSION

The equipment with adaptations seems to be functional, easy to handle, and can potentially contribute to clinical and functional improvements in patients with trunk control deficits after stroke.

Diagnosis and Management of Pulmonary Hypertension and Right Ventricular Failure in the Cardiovascular Intensive Care Unit

Pulmonary hypertension (PH) encompasses a broad range of conditions, including pulmonary artery hypertension, left-sided heart disease, and pulmonary and thromboembolic disorders. Successful diagnosis and management rely on an integrated clinical assessment of the patient's physiology and right heart function. Right ventricular (RV) heart failure is often a result of PH, but may result from varying abnormalities in preload, afterload, and intrinsic myocardial dysfunction, which require distinct management strategies. Consideration of an individual's hemodynamic phenotype and physiologic circumstances is paramount in management of PH and RV failure, particularly when there is clinical instability in the intensive care setting.

Importance of timing and training to implement awake prone positioning in patients with COVID-19: a single-center prospective observational study

Background

Awake prone positioning (APP) is broadly implemented in patients with severe acute respiratory syndrome coronavirus 2 related disease [coronavirus disease 2019 (COVID-19)] admitted to hospital with severe respiratory distress syndrome. This prospective observational study aimed to explore the factors influencing the implementation of APP in patients with acute respiratory failure due to COVID-19.

Methods

Patients with COVID-19, all hospitalized with positive X-ray findings and oxygen supplementation requirement, in the Respiratory Step-Down Unit of the Peking University Third Hospital between January 6th, 2023, and January 20th, 2023, were included in this study. Data regarding basic information, activities of daily living (ADLs) scores, oxygen therapy, vital signs, and duration of APP were collected to investigate the factors influencing prone positioning.

Results

Among the 134 patients included, 55.2% showed an improvement in oxygen saturation 1 hour after APP. Logistic regression revealed that the pre-APP heart rate (HR) [odds ratio (OR) =1.032; P=0.046] and peripheral oxygen saturation (SpO2) (OR =0.720; P<0.001) were the associated factors of the improvement in SpO2 after treatment. Multiple linear regression revealed that the ADL scores and pre-APP respiratory rate (RR) were the associated factors of the duration of prone positioning (P<0.01). The APP technical steering group effectively improved duration of APP.

Conclusions

Patients with low SpO2 and increased HR before treatment showed greater improvement in oxygen saturation. Patients with lower tolerance to ADL but lower RRs were those to demonstrate a longer duration of prone positioning. This is pointing towards establishing the most favorable time window for APP during the course of COVID-19: after the ADLs have already decreased, but before significant tachypnea has appeared.

Dual lumen cannulation and mobilization of patients with venovenous extracorporeal membrane oxygenation

BACKGROUND

Mobilization is important in longer courses in intensive care unit (ICU), typical for patients requiring venovenous extracorporeal membrane oxygenation (V-V ECMO). For patients supported with ECMO, especially out-of-bed mobilizations improve outcome. We hypothesized that utilization of a dual lumen cannula (DLC) for V-V ECMO would facilitate out-of-bed mobilization compared to single lumen cannulas (SLC).

METHODS

Retrospective single center registry study including all V-V ECMO patients cannulated between 10/2010 and 05/2021 for respiratory failure.

RESULTS

The registry included 355 V-V ECMO patients (median age 55.6 years, 31.8% female, 27.3% with preexisting pulmonary disease), 289/355 (81.4%) primary cannulated with DLC, and 66/355 (18.6%) using SLC. Both groups had similar pre-ECMO characteristics. The runtime of the first ECMO cannula was significantly longer in DLC compared to SLC (169 vs. 115 h, p = 0.015). The frequency of prone positioning during V-V ECMO was similar in both groups (38.4 vs. 34.8%, p = 0.673). There was no difference in in-bed mobilization (41.2 vs. 36.4%, for DLC and SLC, respectively, p = 0.491). Patients with DLC were more often mobilized out-of-bed (25.6 vs. 12.1%, OR 2.495 [95% CI 1.150 to 5.268], for DLC and SLC, respectively, p = 0.023). Hospital survival was similar in both groups (46.4 vs. 39.4%, for DLC and SLC, respectively, p = 0.339).

CONCLUSION

Patients cannulated with a dual lumen cannula for V-V ECMO support were significantly more often mobilized out-of-bed. Since mobilization is important in prolonged ICU courses typical for ECMO patients, this might be an important benefit. Other benefits of DLC were the longer runtime of the initial cannula set and fewer suction events.

Pronation Reveals a Heterogeneous Response of Global and Regional Respiratory Mechanics in Patients With Acute Hypoxemic Respiratory Failure

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 H2O to 6 cm H2O 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 H2O. 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.

Mobilisation practices during the SARS-CoV-2 pandemic: A retrospective analysis (MobiCOVID)

BACKGROUND

Corona Virus Disease 2019 (COVID-19) patients display risk factors for intensive care unit acquired weakness (ICUAW). The pandemic increased existing barriers to mobilisation. This study aimed to compare mobilisation practices in COVID-19 and non-COVID-19 patients.

METHODS

This retrospective cohort study was conducted at Charité-Universitätsmedizin Berlin, Germany, including adult patients admitted to one of 16 ICUs between March 2018, and November 2021. The effect of COVID-19 on mobilisation level and frequency, early mobilisation (EM) and time to active sitting position (ASP) was analysed. Subgroup analysis on COVID-19 patients and the ICU type influencing mobilisation practices was performed. Mobilisation entries were converted into the ICU mobility scale (IMS) using supervised machine learning. The groups were matched using 1:1 propensity score matching.

RESULTS

A total of 12,462 patients were included, receiving 59,415 mobilisations. After matching 611 COVID-19 and non-COVID-19 patients were analysed. They displayed no significant difference in mobilisation frequency (0.4 vs. 0.3, p = 0.7), maximum IMS (3 vs. 3; p = 0.17), EM (43.2% vs. 37.8%; p = 0.06) or time to ASP (HR 0.95; 95% CI: 0.82, 1.09; p = 0.44). Subgroup analysis showed that patients in surge ICUs, i.e., temporarily created ICUs for COVID-19 patients during the pandemic, more commonly received EM (53.9% vs. 39.8%; p = 0.03) and reached higher maximum IMS (4 vs. 3; p = 0.03) without difference in mobilisation frequency (0.5 vs. 0.3; p = 0.32) or time to ASP (HR 1.15; 95% CI: 0.85, 1.56; p = 0.36).

CONCLUSION

COVID-19 did not hinder mobilisation. Those treated in surge ICUs were more likely to receive EM and reached higher mobilisation levels.

Nursing strategies for the mechanically ventilated patient

The goal of this manuscript is to provide a comprehensive and multi-disciplinary review of the best nursing practices of caring for mechanically ventilated patients. By reviewing human medicine literature, the authors will extrapolate procedures that have been found to be most effective in reducing the risk of mechanical ventilation (MV) complications. Paired with review of the current standards in veterinary medicine, the authors will compile the best practice information on mechanically ventilated patient care, which will serve as a detailed resource for the veterinary nursing staff. Written from a nursing standpoint, this manuscript aims to consolidate the nursing assessment of a mechanically ventilated patient, addressing both systemic and physical changes that may be encountered during hospitalization. The goal of this review article is to present information that encourages a proactive approach to nursing care by focusing on understanding the effects of polypharmacy, hemodynamic changes associated with MV, complications of recumbent patient care, and sources of hospital acquired infections. When applied in conjunction with the more technical aspects of MV, this manuscript will allow veterinary technicians involved in these cases to understand the dynamic challenges that mechanically ventilated patients present, provide guidance to mitigate risk, address issues quickly and effectively, and create an up-to date standard of practice that can be implemented.

Does Good Nebulization Therapy in the Emergency Room Reduce the Need for Hospitalization in Asthmatic Children?

INTRODUCTION

Asthma is a chronic inflammatory disorder characterized by obstruction, hyperresponsiveness, and inflammatory changes in the airways. The overall prevalence of asthma in Saudi Arabian children ranges from 8% to 25%. Studies have shown that children who did not respond adequately to treatment in the emergency room (ER) were admitted to hospital for additional treatment which increased the cost and risk of hospital-acquired infections. The quality of nebulization therapy is influenced by several factors such as the position, dose, oxygen flow rate, and duration of treatment.  Objectives: In this study, we aimed to explore factors that affect nebulization therapy in ER and to assess the relation between nebulization technique in ER and hospital admission for asthmatic children, and these aims were achieved over the period from December 2021 to May 2023.

METHODOLOGY

An observational cross-sectional study was conducted in Maternity and Children Hospital (MCH) in Medina at the ER over the period from December 2021 to May 2023 for all children admitted to ER with asthma exacerbation. The sample size used to include patients in the study is 289 calculated using the Openepi website. Data were collected by observation and using medical records of the patients and analyzed using Statistical Package for Social Sciences (SPSS) version 26.0 (IBM Corp., Armonk, NY, USA).

RESULTS

The total number of the sample was 289 children ages between two to 14 years. Sixty-four percent (n=185) reported as their gender as male while 36% (n = 104) as female. The median age of the children was four years old (interquartile range [IQR] = 4), and their median weight was 15 kg (IQR = 8.15). Also, more than 83% of the patients has mild asthma, while 16.3% of the sample were diagnosed with moderate to severe asthma. Besides, 92.4% of the sample was discharged from a hospital, and 76.5% received an appropriate dose of nebulization.

DISCUSSION

After reviewing the results of the statistical analysis, the main findings were that the severity of asthma exacerbation was the most important factor influencing the outcome. It was found that 0.4% of patients with mild asthma were admitted to the hospital, compared to 44.7% of patients with moderate to severe asthma.

CONCLUSION

Our study assessed whether effective nebulization therapy in the ER will reduce the need for hospitalization in asthmatic children and the results indicate that the severity of asthma exacerbation was the most significant factor impacting hospital admission in asthmatic patients and influenced other factors of nebulization therapy. However, the other factors, such as the patient position, oxygen flow rate, and the dose of medications did not show any clinically significant impact on hospitalization rates.

Prone Positioning for Acute Hypoxemic Respiratory Failure and ARDS: A Review

Prone positioning is an immediately accessible, readily implementable intervention that was proposed initially as a method for improvement in gas exchange > 50 years ago. Initially implemented clinically as an empiric therapy for refractory hypoxemia, multiple clinical trials were performed on the use of prone positioning in various respiratory conditions, cumulating in the landmark Proning Severe ARDS Patients trial, which demonstrated mortality benefit in patients with severe ARDS. After this trial and the corresponding meta-analysis, expert consensus and societal guidelines recommended the use of prone positioning for the management of severe ARDS. The ongoing COVID-19 pandemic has brought prone positioning to the forefront of medicine, including widespread implementation of prone positioning in awake, spontaneously breathing, nonintubated patients with acute hypoxemic respiratory failure. Multiple clinical trials now have been performed to investigate the safety and effectiveness of prone positioning in these patients and have enhanced our understanding of the effects of the prone position in respiratory failure. In this review, we discuss the physiologic features, clinical outcome data, practical considerations, and lingering questions of prone positioning.

Inspiratory and end-expiratory effects of lung recruitment in the prone position on dorsal lung aeration - new physiological insights in a secondary analysis of a randomised controlled study in post-cardiac surgery patients

Background

Cardiac surgery produces dorso-basal atelectasis and ventilation/perfusion mismatch, associated with infection and prolonged intensive care. A postoperative lung volume recruitment manoeuvre to decrease the degree of atelectasis is routine. In patients with severe respiratory failure, prone positioning and recruitment manoeuvres may increase survival, oxygenation, or both. We compared the effects of lung recruitment in prone vs supine positions on dorsal inspiratory and end-expiratory lung aeration.

Methods

In a prospective RCT, 30 post-cardiac surgery patients were randomly allocated to recruitment manoeuvres in the prone (n=15) or supine position (n=15). The primary endpoints were late dorsal inspiratory volume (arbitrary units [a.u.]) and left/right dorsal end-expiratory lung volume change (a.u.), prone vs supine after extubation, measured using electrical impedance tomography. Secondary outcomes included left/right dorsal inspiratory volumes (a.u.) and left/right dorsal end-expiratory lung volume change (a.u.) after prone recruitment and extubation.

Results

The last part of dorsal end-inspiratory volume after extubation was higher after prone (49.1 a.u.; 95% confidence interval [CI], 37.4-60.6) vs supine recruitment (24.2 a.u.; 95% CI, 18.4-29.6; P=0.024). Improvement in left dorsal end-expiratory lung volume after extubation was higher after prone (382 a.u.; 95% CI, 261-502) vs supine recruitment (-71 a.u., 95% CI, -140 to -2; n=15; P<0.001). After prone recruitment, left vs right predominant end-expiratory dorsal lung volume change disappeared after extubation. However, both left and right end-expiratory volumes were higher in the prone group, after extubation.

Conclusions

Recruitment in the prone position improves dorsal inspiratory and end-expiratory lung volumes after cardiac surgery.

Clinical trial registration

NCT03009331.

How the work of respiratory physiotherapists changes the tracheostomy management and decannulation in a NICU department: an Italian experience

Tracheotomy is a clinical procedure that is often necessary though not without complications, hence the need for appropriate and timely decannulation. The inclusion of trained respiratory physiotherapists (RPT) in the staff and the use of shared protocols could help the team to manage the patient with tracheotomy cannula. The objective of this study was to describe the difference in the rate of decannulation and clinical outcomes of tracheostomized patients admitted to a NeuroIntensive Care Unit (NICU) team after the inclusion of a group of physiotherapists specialized in respiratory physiotherapy and a new phoniatric protocol. It is a 6-year retrospective study, in which two periods of 3 years each were compared: in the first period (P1: September 2013-August 2016) physiotherapists were called to treat NICU patients on a consultative basis (2 hours/day for 5 days a week); in the second period (P2: September 2016-August 2019) two full-time respiratory physiotherapists were present on the ward (7 hours/day, 6/7 days/week). In P2 period, a decannulation protocol was used. Patients who had undergone a tracheotomy procedure and who were alive at the time of discharge were retrospectively evaluated. We described the number of decannulations, the length of stay in NICU and decannulation time; the diagnosis of decannulated patients and the number of deaths. 928 total patients were analysed: 468 in P1, 460 in P2. Total length of stay or number of deaths did not change significantly between the two periods, while the number of decannulated patients before the discharge was higher in P2 143 (64%), compared with P1 79 (36%) p<0.001. More patients with neurological pathologies involving possible swallowing disorders, such as cerebral haemorrhage, head trauma and stroke, have been successfully decannulated in P2 than in P1 (120 patients in P2 vs 54 in P1). A multidisciplinary approach, including respiratory physiotherapist, dedicated to tracheostomy management, decannulation and early mobilization in NICU is safe, feasible and seems to improve the number of severe patients decannulated, even if no change was observed in NICU length of stay or deaths. Further studies must confirm our results in other ICU settings.

Esophageal Pressure Measurement in Acute Hypercapnic Respiratory Failure Due to Severe COPD Exacerbation Requiring NIV-A Pilot Safety Study

Esophageal pressure (Pes) measurements could optimise ventilator parameters in acute respiratory failure (ARF) patients requiring noninvasive ventilation (NIV). Consequently, the objectives of our study were to evaluate the safety and accuracy of applying a Pes measuring protocol in ARF patients with AECOPD under NIV in our respiratory intermediate care unit (RICU). An observational cohort study was undertaken. The negative inspiratory swing of Pes (ΔPes) was measured: in an upright/supine position in the presence/absence of NIV at D1 (day of admission), D3 (3rd day of NIV), and DoD (day of discharge). A digital filter for artefact removal was developed. We included 15 patients. The maximum values for ∆Pes were recorded at admission (mean ∆Pes 23.2 cm H2O) in the supine position. ∆Pes decreased from D1 to D3 (p < 0.05), the change being BMI-dependent (p < 0.01). The addition of NIV decreased ∆Pes at D1 and D3 (p < 0.01). The reduction of ∆Pes was more significant in the supine position at D1 (8.8 cm H2O, p < 0.01). Under NIV, ∆Pes values remained higher in the supine versus upright position. Therefore, the measurement of Pes in AECOPD patients requiring NIV can be safely done in an RICU. Under NIV, ∆Pes reduction is most significant within the first 24 h of admission.

Chest wall loading in the ICU: pushes, weights, and positions

Clinicians monitor mechanical ventilatory support using airway pressures—primarily the plateau and driving pressure, which are considered by many to determine the safety of the applied tidal volume. These airway pressures are influenced not only by the ventilator prescription, but also by the mechanical properties of the respiratory system, which consists of the series-coupled lung and chest wall. Actively limiting chest wall expansion through external compression of the rib cage or abdomen is seldom performed in the ICU. Recent literature describing the respiratory mechanics of patients with late-stage, unresolving, ARDS, however, has raised awareness of the potential diagnostic (and perhaps therapeutic) value of this unfamiliar and somewhat counterintuitive practice. In these patients, interventions that reduce resting lung volume, such as loading the chest wall through application of external weights or manual pressure, or placing the torso in a more horizontal position, have unexpectedly improved tidal compliance of the lung and integrated respiratory system by reducing previously undetected end-tidal hyperinflation. In this interpretive review, we first describe underappreciated lung and chest wall interactions that are clinically relevant to both normal individuals and to the acutely ill who receive ventilatory support. We then apply these physiologic principles, in addition to published clinical observation, to illustrate the utility of chest wall modification for the purposes of detecting end-tidal hyperinflation in everyday practice.

Efficacy of Physiotherapy Interventions on Weaning in Mechanically Ventilated Critically Ill Patients: A Systematic Review and Meta-Analysis

Mechanical ventilation (MV) is currently considered a life-saving intervention. However, growing evidence highlighted that prolonged MV significantly affects functional outcomes and length of stay. In this scenario, controversies are still open about the optimal rehabilitation strategies for improving MV duration in ICU patients. In addition, the efficacy of physiotherapy interventions in critical ill patients without positive history of chronic respiratory conditions is still debated. Therefore, this systematic review of randomized controlled trials (RCTs) with meta-analysis aimed at characterizing the efficacy of a comprehensive physiotherapy intervention in critically ill patients. PubMed, Scopus, and Web of Science databases were systematically searched up to October 22, 2021 to identify RCTs assessing acute patients mechanical ventilated in ICU setting undergoing a rehabilitative intervention. The primary outcomes were MV duration, extubation, and weaning time. The secondary outcomes were weaning successful rate, respiratory function, ICU discharge rate and length of stay. Out of 2503 records, 12 studies were included in the present work. The meta-analysis performed in 6 RCTs showed a significant improvement in terms of MV duration (overall effect size: −3.23 days; 95% CI = −5.79, −0.67, p = 0.01; Z = 2.47) in patients treated with a comprehensive physiotherapy intervention including early mobilization, positioning, airway clearance techniques, lung expansion and respiratory muscle training. The quality assessment underlined 9 studies (75%) of good quality and 3 studies of fair quality according to the PEDro scale. In conclusion, our results provided previously unavailable data about the role of comprehensive physiotherapy intervention in improving MV duration in critical ill patients without chronic respiratory conditions. Further studies are needed to better characterize the optimal combination of rehabilitation strategies enhancing the improvements in critical ill patients without chronic respiratory disorders.

Effect of head-end of bed elevation on respiratory mechanics in mechanically ventilated patients with moderate-to-severe COVID-19 ARDS - A cohort study

Background

Head-end elevation (HEE) is known to improve oxygenation and respiratory mechanics. In ARDS, poor lung compliance limits positive pressure ventilation causing delivery of inadequate minute ventilation (MVe). We observed that, in moderate-to-severe COVID-19 ARDS, the respiratory system compliance (Crs) reduces upon elevating the head-end of the bed, and vice-versa, which can be utilized to improve ventilation and avoid respiratory acidosis.We hypothesized that increasing the degree of HEE reduces Crs.

Methods

We included 20 consecutive mechanically ventilated, moderate-to-severe COVID-19 ARDS patients in this pilot study (CTRI/2021/06/034,182). The Crs, Mve and Rinsp were recorded at 0°, 10°, 20° and 30° HEE. Repeated measures ANOVA was used to determine significant differences in measurements with increasing degrees and repeated measures correlation (rmcorr) for correlation.

Results

Repeated measures ANOVA showed a significant difference (p < 0.0001) between values of Crs, MVe and Rinsp. Rmcorr showed a strong negative correlation between increasing degrees and Crs and Mve (r-0.87 [95% CI -0.79 to -0.92, p < 0.0001 and r-0.77 [95% CI -0.64 to -0.85, p < 0.0001]) and a moderate negative correlation for Rinsp (r-0.67; 95% CI -0.79 to -0.50; p < 0.0001).

Conclusions

Increasing degree of HEE reduces compliance in moderate-to-severe COVID-19 ARDS. Reducing HEE may optimize ventilation and mitigate ventilator induced lung injury.

Differential Prognostic Analysis of Higher and Lower PEEP in ARDS Patients: Systematic Review and Meta-Analysis

Background

Positive end-expiratory pressure (PEEP) refers to the positive pressure in the respiratory tract at the end of the exhalation when we use a ventilator. The differences of higher PEEP and lower PEEP on clinical outcomes in acute respiratory distress syndrome (ARDS) patients are less well known.

Methods

A comprehensive literature search of all randomized control trials (RCTs) was conducted using PubMed, Embase, World Health Organization (WHO) Global Index Medicus, WHO clinical trial registry, and Clinicaltrials.gov. Inclusion criteria included RCTs comparing the clinical outcomes of higher and lower PEEP in ARDS patients.

Results

Eleven studies were included in the final analysis. In the higher PEEP group, the hospital mortality, 28-day mortality, and ICU mortality showed no significantly lower risk compared to the lower PEEP group (RR = 0.92, 95% CI 0.80-1.05, p = 0.22; RR = 0.88, 95% CI 0.73-1.05, p = 0.15; RR = 0.84, 95% CI 0.67-1.05, p = 0.12; respectively). High certainty could be obtained that there is no significant difference between the clinical outcomes of higher PEEP and lower PEEP in ARDS patients.

Conclusions

There is no significant difference of the hospital mortality, 28-day mortality, and ICU mortality between higher and lower PEEP in ARDS patients.

Silent Hypoxia in COVID-19 Pneumonia: State of Knowledge, Pathophysiology, Mechanisms, and Management

Patients with COVID-19 often present with life-threatening hypoxemia without dyspnea or signs of respiratory distress. Termed silent or happy hypoxia, it has puzzled clinicians and challenged and defied our understanding of normal respiratory physiology. A range of host- and pathogen-related factors appears to contribute to its development, including SARS-CoV-2's ability to produce different COVID-19 phenotypes; induce endothelial damage and elicit a vascular distress response; invade cells of the central nervous system and disrupt normal interoception and response; and modulate transcription factors involved in hypoxic responses. Because hypoxemia in COVID-19 is associated with increased mortality risk and poorer survival, early detection and prompt treatment is essential to prevent potential complications. Interventions to prevent hypoxemia and improve oxygen delivery to the blood and the tissues include home pulse-oximetry monitoring, optimization of patient positioning, judicious use of supplemental oxygen, breathing control exercises, and timely and appropriate use of ventilatory modalities and adjuncts.

Effects of the Prone Position on Regional Neutrophilic Lung Inflammation According to 18F-FDG Pet in an Experimental Ventilator-Induced Lung Injury Model

ABSTRACT

Ventilator-induced lung injury (VILI) can be life-threatening and it is important to prevent the development of VILI. It remains unclear whether the prone position affects neutrophilic inflammation in the lung regions in vivo, which plays a crucial role in the pathogenesis of VILI. This study aimed to assess the relationship between the use of the prone position and the development of VILI-associated regional neutrophilic lung inflammation. Regional neutrophilic lung inflammation and lung aeration during low tidal volume mechanical ventilation were assessed using in vivo 2-deoxy-2-[(18)F] fluoro-D-glucose (18F-FDG) positron emission tomography and computed tomography in acutely experimentally injured rabbit lungs (lung injury induced by lung lavage and excessive ventilation). Direct comparisons were made among three groups: control, supine, and prone positions. After approximately 7 h, tissue-normalized 18F-FDG uptake differed significantly between the supine and prone positions (SUP: 0.038 ± 0.014 vs. PP: 0.029 ± 0.008, P = 0.038), especially in the ventral region (SUP: 0.052 ± 0.013 vs. PP: 0.026 ± 0.007, P = 0.003). The use of the prone position reduced lung inhomogeneities, which was demonstrated by the correction of the disproportionate rate of voxel gas over the given lung region. The progression of neutrophilic inflammation was affected by the interaction between the total strain (for aeration) and the inhomogeneity. The prone position is effective in slowing down the progression of VILI-associated neutrophilic inflammation. Under low-tidal-volume ventilation, the main drivers of its effect may be homogenization of lung tissue and that of mechanical forces.

Effect of pursed-lip breathing and forward trunk lean positions on regional chest wall volume and ventilatory pattern in older adults: An observational study

ABSTRACT

Pursed-lip breathing (PLB) and forward trunk lean posture (FTLP) are commonly used to relieve dyspnea and improve ventilation in a rehabilitation program. However, their effect on chest wall volumes and movements in older adults without chronic obstructive pulmonary disease has never been investigated. This observational study aimed to identify the effect of combined PLB and FTLP on total and regional chest wall volumes, ventilatory pattern, and thoracoabdominal movement using in older adults. It was hypothesized that the combined PLB with FTLP would result in the highest chest wall volumes among the experimental tasks. Twenty older adults performed 2 breathing patterns of quiet breathing (QB) and PLB during a seated upright (UP) position and FTLP. An optoelectronic plethysmography system was used to capture the chest wall movements during the 4 experimental tasks. Tidal volume (VT) was separated into pulmonary ribcage, abdominal ribcage, and abdomen volume. The changes in anterior-posterior (AP) and medial-lateral (ML) chest wall diameters at 3 levels were measured and used to identify chest wall mechanics to improve chest wall volumes. The PLB significantly improved ventilation and chest wall volumes than the QB (P < .05). VT of pulmonary ribcage, VT of abdominal ribcage, and VT were significantly higher during the PLB + UP (P < .05) and during the PLB + FTLP (P < .01) as compared to those of QB performed in similar body positions. However, there was no significant in total and regional lung volumes between the PLB + UP and the PLB + FTLP. The AP diameter changes at the angle of Louis and xiphoid levels were greater during the PLB + UP than the QB + UP and the QB + FTLP (P < .01). The AP diameter changes at the umbilical level and the ML diameter changes at the xiphoid level were significantly larger during the PLB + FTLP than the QB + FTLP and the QB + UP (P < .05). The ML diameter changes at the umbilical level were significantly greater during the PLB + FTLP than the QB + UP (P < .05). However, no significant difference in the relative regional chest wall volumes and phase angle among the experimental tasks (P > .05). In conclusion, a combined PLB performed in an FTLP or UP sitting could be used as a strategy to improve chest wall volumes and ventilation in older adults.

Perioperative Pulmonary Atelectasis: Part II. Clinical Implications

The development of pulmonary atelectasis is common in the surgical patient. Pulmonary atelectasis can cause various degrees of gas exchange and respiratory mechanics impairment during and after surgery. In its most serious presentations, lung collapse could contribute to postoperative respiratory insufficiency, pneumonia, and worse overall clinical outcomes. A specific risk assessment is critical to allow clinicians to optimally choose the anesthetic technique, prepare appropriate monitoring, adapt the perioperative plan, and ensure the patient's safety. Bedside diagnosis and management have benefited from recent imaging advancements such as lung ultrasound and electrical impedance tomography, and monitoring such as esophageal manometry. Therapeutic management includes a broad range of interventions aimed at promoting lung recruitment. During general anesthesia, these strategies have consistently demonstrated their effectiveness in improving intraoperative oxygenation and respiratory compliance. Yet these same intraoperative strategies may fail to affect additional postoperative pulmonary outcomes. Specific attention to the postoperative period may be key for such outcome impact of lung expansion. Interventions such as noninvasive positive pressure ventilatory support may be beneficial in specific patients at high risk for pulmonary atelectasis (e.g., obese) or those with clinical presentations consistent with lung collapse (e.g., postoperative hypoxemia after abdominal and cardiothoracic surgeries). Preoperative interventions may open new opportunities to minimize perioperative lung collapse and prevent pulmonary complications. Knowledge of pathophysiologic mechanisms of atelectasis and their consequences in the healthy and diseased lung should provide the basis for current practice and help to stratify and match the intensity of selected interventions to clinical conditions.

Effect of Position Change From the Bed to a Wheelchair on the Regional Ventilation Distribution Assessed by Electrical Impedance Tomography in Patients With Respiratory Failure

Background: There is limited knowledge about the effect of position change on regional lung ventilation in patients with respiratory failure. This study aimed to examine the physiological alteration of regional lung ventilation during the position change from lying in bed to sitting on a wheelchair.

Methods: In this study, 41 patients with respiratory failure who were weaned from the ventilators were prospectively enrolled. The electrical impedance tomography (EIT) was used to assess the regional lung ventilation distribution at four time points (T_base: baseline, supine position in the bed, T_30min: sitting position in the wheelchair after 30 min, T_60min: sitting position in the wheelchair after 60 min, T_return: the same supine position in the bed after position changing). The EIT-based global inhomogeneity (GI) and center of ventilation (CoV) indices were calculated. The EIT images were equally divided into four ventral-to-dorsal horizontal regions of interest (ROIs 1–4). Depending on the improvement in ventilation distribution in the dependent regions at T_60min (threshold set to 15%), the patients were divided into the dorsal ventilation improved (DVI) and not improved (non-DVI) groups.

Results: When the patients moved from the bed to a wheelchair, there was a significant and continuous increase in ventilation in the dorsal regions (ROI 3 + 4: 45.9 ± 12.1, 48.7 ± 11.6, 49.9 ± 12.6, 48.8 ± 10.6 for T_base, T_30min, T_60min, and T_return, respectively; p = 0.015) and CoV (48.2 ± 10.1, 50.1 ± 9.2, 50.5 ± 9.6, and 49.5 ± 8.6, p = 0.047). In addition, there was a significant decrease in GI at T_60min compared with T_base. The DVI group (n = 18) had significantly higher oxygenation levels than the non-DVI group (n = 23) after position changing. ROI4_Tbase was significantly negatively correlated with the ΔSpO₂ (R = 0.72, p < 0.001). Using a cutoff value of 6.5%, ROI4_Tbase had 79.2% specificity and 58.8% sensitivity in indicating the increase in the dorsal region related to the position change. The corresponding area under the curve (AUC) was 0.806 (95% CI, 0.677–0.936).

Conclusions: Position change may improve the ventilation distribution in the study patients. The EIT can visualize real-time changes of the regional lung ventilation at the bedside to guide the body position change of the patients in the intensive care unit (ICU) and measure the effect of clinical practice.

Trial Registration: Effect of Early Mobilization on Regional Lung Ventilation Assessed by EIT, NCT04081129. Registered 9 June 2019—Retrospectively registered. https://register.clinicaltrials.gov/prs/app/action/SelectProtocol?sid=S00096WT&selectaction=Edit&uid=U00020D9&ts=2&cx=v2cwij.

Investigation of the influence of manual ventilation-controlled respiration on right ventricular pressure-volume loops and echocardiographic variables in healthy anesthetized dogs

OBJECTIVE

To evaluate the influence of manual ventilation-controlled respiration on right ventricular (RV) pressure-volume loop-derived and echocardiographic variables in dogs.

ANIMALS

8 healthy, anesthetized Beagles.

PROCEDURES

In a prospective experimental study, pressure-volume catheters were percutaneously inserted into the right ventricle of each dog, and manual ventilation was performed; RV pressure-volume loop (hemodynamic) data and conventional echocardiographic variables were assessed. Two-dimensional speckle tracking echocardiography-derived RV strain (RVS) and RV systolic strain rate (RVSR) were obtained with RV free wall-only analysis (free wall) and RV global analysis (RVGA; interventricular septum). Variables were compared between end-inspiratory and end-expiratory phases of respiration by statistical methods. Multiple regression analysis was used to assess associations between selected hemodynamic and echocardiographic variables.

RESULTS

The RV pressure significantly increased, and RV volume, stroke volume, tricuspid annular plane systolic excursion, RV fractional area change, peak myocardial systolic velocity of the lateral tricuspid annulus, and RV free wall only-assessed RVS and RVSR significantly decreased in the inspiratory phase, compared with the expiratory phase. There were no significant differences in end-systolic elastance or RVGA-assessed RVS or RVSR between respiratory phases. The RVGA-assessed RVSR was significantly associated with stroke volume and end-systolic elastance.

CONCLUSIONS AND CLINICAL RELEVANCE

Specific RV echocardiographic variables were significantly affected by respiration. In contrast, RVS and RVSR determined with RVGA were not affected by respiration and were associated with hemodynamic indicators of RV contractility.

Cardiopulmonary effects of prolonged surgical abdominal retractors application during general anesthesia: a prospective observational comparative study

INTRODUCTION

Increasing abdominal pressures could affect pulmonary compliance and cardiac performance, a fact based on which the aim of the present study to detect the cardiopulmonary burden of multiple retractors application during supine versus lateral abdominal surgeries. We hypothesized that surgical ring multiple retractors application would affect the pulmonary and cardiac functions during both lateral and supine abdominal surgeries.

METHODS

Prospective observational comparative study on forty surgical patients subdivided into two groups twenty each, comparing pulmonary compliance and cardiac performance before, during and after retractors application, group (S) supine position cystectomy surgery, and group (L) lateral position nephrectomy surgery under general anesthesia, Composite 1ry outcome; dynamic compliance C-dyn and cardiac index CI and Other outcome variables ICON cardio-meter were also recorded.

RESULTS

C-dyn and C-stat were significantly decreased late during retractor application in lateral compared to supine surgery with significant decrease compared to basal values all over the surgical time. CI was significantly increased after retractor removal in both of the study groups compared to basal values. PAWP was significantly increased in -lateral compared to supine surgery -with significant increase compared to basal value all over the surgical time in both of the study groups. significant increase in DO2I compared to basal value during both supine and lateral positions.

CONCLUSION

Surgical retraction results in a short-lived significant decreases in lung compliance and cardiac output particularly during the lateral-kidney position than the supine position compliance.

Continuous Endotracheal Tube Cuff Pressure Control Decreases Incidence of Ventilator-Associated Pneumonia in Patients with Traumatic Brain Injury

BACKGROUND

Ventilator-associated pneumonia (VAP) is a common cause of morbidity and mortality in intensive care unit (ICU), and among the several preventative strategies described to reduce the incidence of VAP, the most important is the endotracheal tube cuff (ETC) pressure. The present study was conducted on 60 patients who required mechanical ventilation (MV) in the ICU with traumatic brain injury (TBI).

METHODS

The patients were randomized into two groups of 30, in which ETC pressure was regulated using a smart cuff manager (SCM) (Group II), or manual measurement approach (MMA) (Group I). Demographic data, MV duration, length of ICU stay and mortality rates were recorded. The clinical pulmonary infection scores (CPISs), C-reactive protein (CRP) values, and the fraction of inspired oxygen (FiO2) and positive end-expiratory pressure (PEEP) values of the groups were compared at baseline, and at hours 48, 72 and 96.

RESULTS

In Group I, CPIS values significantly higher than Group II in 48th, 72nd and 96th hours (p < 0.05). In Group I, PEEP values and deep tracheal aspirate (DTA) culture growth rates significantly higher than Group II in 72nd and 96th hours (p < 0.05).

CONCLUSION

The continuous maintenance of ETC pressure using SCM reduced the incidence of VAP.

The effect of reverse Trendelenburg position versus semi-recumbent position on respiratory parameters of obese critically ill patients: A randomised controlled trial

AIMS AND OBJECTIVES

To investigate the effect of reverse Trendelenburg position versus semi-recumbent position on respiratory parameters of obese critically ill patients.

BACKGROUND

Reverse Trendelenburg position is recommended for obese patients; however, the effect among critically ill patients, especially those on mechanical ventilation, has limited study.

DESIGN

Randomised, controlled pretest, repeated post-test trial with two parallel groups.

METHODS

The study started from 13 January 2020-12 March 2020. Adult critically ill patients with a body mass index ≥30 were randomly assigned by computer-generated randomisation to either reverse Trendelenburg position group (intervention) or semi-recumbent position group (active comparator control). Outcome measures were ventilation parameters (dynamic compliance, partial pressure of arterial carbon dioxide and minute volume) and oxygenation parameters (hypoxaemic index and partial pressure of arterial oxygen). Measures were assessed immediately before positioning and after positioning in 10 minutes, 20 minutes and 30 minutes. CONSORT checklist was used to report the current study.

SETTINGS

Four general intensive care units.

RESULTS

One hundred and ten patients (55 patients in each group) completed the study. The reverse Trendelenburg position group had a higher improvement than the semi-recumbent position group as estimated by mean differences in their dynamic compliance, minute volume, partial pressure of carbon dioxide, partial pressure of oxygen and hypoxaemic index.

CONCLUSION

Reverse Trendelenburg position improves obese patients' respiratory parameters more than semi-recumbent position.

RELEVANCE TO CLINICAL PRACTICE

This study directs nurses to use the reverse Trendelenburg position, which is an important position for enhancing the parameters of ventilation and oxygenation of obese mechanically ventilated patients.

Prone positioning improves oxygenation and lung recruitment in patients with SARS-CoV-2 acute respiratory distress syndrome; a single centre cohort study of 20 consecutive patients

Objective

We aimed to characterize the effects of prone positioning on respiratory mechanics and oxygenation in invasively ventilated patients with SARS-CoV-2 ARDS.

Results

This was a prospective cohort study in the Intensive Care Unit (ICU) of a tertiary referral centre. We included 20 consecutive, invasively ventilated patients with laboratory confirmed SARS-CoV-2 related ARDS who underwent prone positioning in ICU as part of their management. The main outcome was the effect of prone positioning on gas exchange and respiratory mechanics. There was a median improvement in the PaO₂/FiO₂ ratio of 132 in the prone position compared to the supine position (IQR 67–228). We observed lower PaO₂/FiO₂ ratios in those with low (< median) baseline respiratory system static compliance, compared to those with higher (> median) static compliance (P < 0.05). There was no significant difference in respiratory system static compliance with prone positioning. Prone positioning was effective in improving oxygenation in SARS-CoV-2 ARDS. Furthermore, poor respiratory system static compliance was common and was associated with disease severity. Improvements in oxygenation were partly due to lung recruitment. Prone positioning should be considered in patients with SARS-CoV-2 ARDS.

Lung mechanics in type L CoVID-19 pneumonia: a pseudo-normal ARDS

BACKGROUND

This study was conceived to provide systematic data about lung mechanics during early phases of CoVID-19 pneumonia, as long as to explore its variations during prone positioning.

METHODS

We enrolled four patients hospitalized in the Intensive Care Unit of "M. Bufalini" hospital, Cesena (Italy); after the positioning of an esophageal balloon, we measured mechanical power, respiratory system and transpulmonary parameters and arterial blood gases every 6 hours, just before decubitus change and 1 hour after prono-supination.

RESULTS

Both respiratory system and transpulmonary compliance and driving pressure confirmed the pseudo-normal respiratory mechanics of early CoVID-19 pneumonia (respectively, C_RS 40.8 ml/cmH₂O and DP_RS 9.7 cmH₂O; C_L 53.1 ml/cmH₂O and DP_L 7.9 cmH₂O). Interestingly, prone positioning involved a worsening in respiratory mechanical properties throughout time (C_RS,SUP 56.3 ml/cmH₂O and C_RS,PR 41.5 ml/cmH₂O - P 0.37; C_L,SUP 80.8 ml/cmH₂O and C_L,PR 53.2 ml/cmH₂O - P 0.23).

CONCLUSIONS

Despite the severe ARDS pattern, respiratory system and lung mechanical properties during CoVID-19 pneumonia are pseudo-normal and tend to worsen during pronation.

TRIAL REGISTRATION

Restrospectively registered.

Repositioning for preventing pressure ulcers: a systematic review and meta-analysis

Objective:

The aim of this systematic review was to assess the effects of different repositioning regimens on pressure ulcer (PU) incidence in at-risk adult individuals without existing PUs.

Method:

Using systematic review methodology, randomised controlled trials (RCTs), including cluster-RCTs, prospective non-RCTs, pre–post-studies and interrupted-time-series studies were considered. Specifically explored was the impact of the frequency of repositioning, use of repositioning systems and use of turning teams. The search was conducted in January 2019, using PubMed, CINAHL, SCOPUS, Cochrane and EMBASE databases. Data were extracted using a pre-designed extraction tool and analysis was undertaken using RevMan.

Results:

A total of 530 records were returned, of which 16 met the inclusion criteria. Half of studies were conducted in intensive care units (50%). The mean sample size was 629±604 participants. Frequency of repositioning was explored in nine studies. PU incidence was 8% (n=221/2834) for repositioning every 2–3 hours, versus 13% (n=398/3050) for repositioning every 4–6 hours. The odds ratio (OR) was 0.75 (95% confidence interval (CI): 0.61–0.90, p=0.03), suggesting that there is a 25% reduction in the odds of PU development in favour of more frequent repositioning. Use of a repositioning system was explored in three studies. PU incidence was 2% (17/865) for the repositioning system, versus 5.5% (51/926) for care without using the repositioning system. The OR was 0.26 (95% CI: 0.05–1.29, p=0.10); this finding was not statistically significant. Use of a turning team was explored in two studies. PU incidence was 11% (n=22/200) with use of a turning team versus 20% (n=40/200) for usual care. The OR was 0.49 (95% CI: 0.27–0.86, p=0.01) suggesting that there is a 51% reduction in the odds of PU development in favour of use of a turning team. Using GRADE appraisal, the certainty of the evidence was assessed as low.

Conclusion:

The results of this systematic review indicate that more frequent repositioning and use of a turning team reduce PU incidence. However, given the low certainty of evidence, results should be interpreted with caution.

Two mechanically ventilated cases of COVID-19 successfully managed with a sequential ventilation weaning protocol: Two case reports

BACKGROUND

Patients with critical coronavirus disease 2019 (COVID-19), characterized by respiratory failure requiring mechanical ventilation (MV), are at high risk of mortality. An effective and practical MV weaning protocol is needed for these fragile cases.

CASE SUMMARY

Here, we present two critical COVID-19 patients who presented with fever, cough and fatigue. COVID-19 diagnosis was confirmed based on blood cell counts, chest computed tomography (CT) imaging, and nuclei acid test results. To address the patients’ respiratory failure, they first received noninvasive ventilation (NIV). When their condition did not improve after 2 h of NIV, each patient was advanced to MV [tidal volume (Vt), 6 mL/kg ideal body weight (IBW); 8-10 cmH₂O of positive end-expiratory pressure; respiratory rate, 20 breaths/min; and 40%-80% FiO₂] with prone positioning for 12 h/day for the first 5 d of MV. Extensive infection control measures were conducted to minimize morbidity, and pharmacotherapy consisting of an antiviral, immune-enhancer, and thrombosis prophylactic was administered in both cases. Upon resolution of lung changes evidenced by CT, the patients were sequentially weaned using a weaning screening test, spontaneous breathing test, and airbag leak test. After withdrawal of MV, the patients were transitioned through NIV and high-flow nasal cannula oxygen support. Both patients recovered well.

CONCLUSION

A MV protocol attentive to intubation/extubation timing, prone positioning early in MV, infection control, and sequential withdrawal of respiratory support, may be an effective regimen for patients with critical COVID-19.

Automated vs. conventional ventilation in the ICU: a randomized controlled crossover trial comparing blood oxygen saturation during daily nursing procedures (I-NURSING)

Background

Hypoxia is common during daily nursing procedures (DNPs) routinely performed on mechanically ventilated patients. The impact of automated ventilation on the incidence and severity of blood oxygen desaturation during DNPs remains unknown.

Methods

A prospective randomized controlled crossover trial was carried out in a French intensive care unit to compare blood oxygen pulse saturation (SpO₂) during DNPs performed on patients mechanically ventilated in automated and conventional ventilation modes (AV and CV, respectively). All patients with FiO₂ ≤ 60% and without prone positioning or neuromuscular blocking agents were included. Patients underwent two DNPs on the same day using AV (INTELLiVENT-ASV®) and CV (volume control, biphasic positive airway pressure, or pressure support ventilation) in a randomized order. The primary outcome was the percentage of time spent with SpO₂ in the acceptable range of 90–95% during the DNP.

Results

Of the 265 included patients, 93% had been admitted for a medical pathology, the majority for acute respiratory failure (52%). There was no difference between the two periods in terms of DNP duration, sedation requirements, or ventilation parameters, but patients had more spontaneous breaths and lower peak airway pressures during the AV period (p <  0.001). The percentage of time spent with SpO₂ in the acceptable range during DNPs was longer in the AV period than in the CV period (48 ± 37 vs. 43 ± 37, percentage of DNP period; p = 0.03). After adjustment, AV was associated with a higher number of DNPs carried out with SpO₂ in the acceptable range (odds ratio, 1.82; 95% CI, 1.28 to 2.6; p = 0.001) and a lower incidence of blood oxygen desaturation ≤ 85% (adjusted odds ratio, 0.50; 95% CI, 0.30 to 0.85; p = 0.01).

Conclusion

AV appears to reduce the incidence and severity of blood oxygen desaturation during daily nursing procedures (DNPs) in comparison to CV.

Trial registration

This study was registered in clinical-trial.gov (NCT03176329) in June 2017.

Graphical abstract

Adverse events during nursing care procedure in intensive care unit: The PREVENIR study

OBJECTIVES

Intensive care unit patients undergo several nursing care procedures (NCP) every day. These procedures involve a risk for adverse events (AE). Yet, their prevalence, intensity, and predisposing risk factors remain poorly established. The main objective of the study was to measure the incidence and severity of NCP related AE.

DESIGN

This prospective observational multicentre study was conducted in 9 ICUs. All NCP were recorded for four consecutive weeks. For each NCP, the following were collected: patients' baseline characteristics, type of NCP, characteristics of the NCP, AE and therapeutic responses.

RESULTS

5849 NCP occurred in 340 patients. Among the 340 patients included, 292 (85.9%) were affected by at least one AE, and 141 (41.5%) by an SAE during a NCP. Thirty % of NCP were associated with at least one AE: hemodynamic AE in 17.1%, respiratory AE in 13.6%, agitation and pain (3.7% and 3.3%). Eight invasive devices were accidentally removed. Severe Adverse Events (SAE) occurred in 5.5% of NCP. The main risk factor associated with SAE was pain/agitation at the beginning of the NCP.

CONCLUSION

AE are frequent during NCP in ICU. We identified several risk factors, some of them preventable, that could be considered for the development of recommendations for the nursing care of critically ill patients.

TRIAL REGISTRATION

ClinicalTrials.gov NCT02881645.

In vivo imaging of canine lung deformation: effects of posture, pneumonectomy, and inhaled erythropoietin

Mechanical stresses on the lung impose the major stimuli for developmental and compensatory lung growth and remodeling. We used computed tomography (CT) to noninvasively characterize the factors influencing lobar mechanical deformation in relation to posture, pneumonectomy (PNX), and exogenous proangiogenic factor supplementation. Post-PNX adult canines received weekly inhalations of nebulized nanoparticles loaded with recombinant human erythropoietin (EPO) or control (empty nanoparticles) for 16 wk. Supine and prone CT were performed at two transpulmonary pressures pre- and post-PNX following treatment. Lobar air and tissue volumes, fractional tissue volume (FTV), specific compliance (Cs), mechanical strains, and shear distortion were quantified. From supine to prone, lobar volume and Cs increased while strain and shear magnitudes generally decreased. From pre- to post-PNX, air volume increased less and FTV and Cs increased more in the left caudal (LCa) than in other lobes. FTV increased most in the dependent subpleural regions, and the portion of LCa lobe that expanded laterally wrapping around the mediastinum. Supine deformation was nonuniform pre- and post-PNX; strains and shear were most pronounced in LCa lobe and declined when prone. Despite nonuniform regional expansion and deformation, post-PNX lobar mechanics were well preserved compared with pre-PNX because of robust lung growth and remodeling establishing a new mechanical equilibrium. EPO treatment eliminated posture-dependent changes in FTV, accentuated the post-PNX increase in FTV, and reduced FTV heterogeneity without altering absolute air or tissue volumes, consistent with improved microvascular blood volume distribution and modestly enhanced post-PNX alveolar microvascular reserves.NEW & NOTEWORTHY Mechanical stresses on the lung impose the major stimuli for lung growth. We used computed tomography to image deformation of the lung in relation to posture, loss of lung units, and inhalational delivery of the growth promoter erythropoietin. Following loss of one lung in adult large animals, the remaining lung expanded and grew while retaining near-normal mechanical properties. Inhalation of erythropoietin promoted more uniform distribution of blood volume within the remaining lung.

Clinical Evaluation of Stretchable and Wearable Inkjet-Printed Strain Gauge Sensor for Respiratory Rate Monitoring at Different Body Postures

Respiratory rate (RR) is a vital sign with continuous, convenient, and accurate measurement which is difficult and still under investigation. The present study investigates and evaluates a stretchable and wearable inkjet-printed strain gauge sensor (IJP) to estimate the RR continuously by detecting the respiratory volume change in the chest area. As the volume change could cause different strain changes at different body postures, this study aims to investigate the accuracy of the IJP RR sensor at selected postures. The evaluation was performed twice on 15 healthy male subjects (mean ± SD of age: 24 ± 1.22 years). The RR was simultaneously measured in breaths per minute (BPM) by the IJP RR sensor and a reference RR sensor (e-Health nasal thermal sensor) at each of the five body postures namely standing, sitting at 90°, Flower’s position at 45°, supine, and right lateral recumbent. There was no significant difference in measured RR between IJP and reference sensors, between two trials, or between different body postures (all p > 0.05). Body posture did not have any significant effect on the difference of RR measurements between IJP and the reference sensors (difference <0.01 BPM for each measurement in both trials). The IJP sensor could accurately measure the RR at different body postures, which makes it a promising, simple, and user-friendly option for clinical and daily uses.

Pulmonary and Physical Rehabilitation in Critically Ill Patients

Some patients admitted to the intensive care unit (ICU) because of an acute illness, complicated surgery, or multiple traumas develop muscle weakness affecting the limbs and respiratory muscles during acute care in the ICU. This condition is referred to as ICU-acquired weakness (ICUAW), and can be evoked by critical illness polyneuropathy (CIP), critical illness myopathy (CIM), or critical illness polyneuromyopathy (CIPNM). ICUAW is diagnosed using the Medical Research Council (MRC) sum score based on bedside manual muscle testing in cooperative patients. The MRC sum score is the sum of the strengths of the 12 regions on both sides of the upper and lower limbs. ICUAW is diagnosed when the MRC score is less than 48 points. However, some patients require electrodiagnostic studies, such as a nerve conduction study, electromyography, and direct muscle stimulation, to differentiate between CIP and CIM. Pulmonary rehabilitation in the ICU can be divided into modalities intended to remove retained airway secretions and exercise therapies intended to improve respiratory function. Physical rehabilitation, including early mobilization, positioning, and limb exercises, attenuates the weakness that occurs during critical care. To perform mobilization in mechanically ventilated patients, pretreatment by removing secretions is necessary. It is also important to increase the strength of respiratory muscles and to perform lung recruitment to improve mobilization in patients who are weaned from the ventilator. For these reasons, pulmonary rehabilitation is important in addition to physical therapy. Early recognition of CIP, CIM, and CIPNM and early rehabilitation in the ICU might improve patients’ functional recovery and outcomes.