Does prone positioning improve oxygenation and reduce mortality in patients with acute respiratory distress syndrome?

The effect of prone-position ventilatory strategy among neurology patients with SARS-CoV-2: A cross-sectional survey

Awake-prone position combined with noninvasive ventilation or high-flow nasal cannula ventilation has been shown to be safe in the treatment of patients with moderate to severe ARDS and COVID-19, and may avoid intubation and reduce patient mortality. We conducted a cross-sectional study in a hospital to observe the effect of prone position on neurological patients with SARS-CoV-2. A total of 52 neurological patients with SARS-CoV-2 participated in the survey. Most patients (76.92%) had cerebrovascular disease combined with SARS-CoV-2. After prone position, the oxygen saturation increased by 3.25% ± 3.02%. The number of patients with an oxygen saturation of 95% or more increased by 28.85%. Among the 3 types of neurological diseases, the oxygen saturation improvement values in patients with encephalitis or encephalopathy was the greatest, and cerebrovascular disease was the least. Oxygen saturation improvements did not differ among delivery modes. Prone position nursing can improve the effect of oxygen therapy on patients with neurological diseases combined with SARS-CoV-2 infection. Prone position nursing can slow the need for advanced equipment such as ventilators during the COVID-19 pandemic.

A Comprehensive Review of Prone Ventilation in the Intensive Care Unit: Challenges and Solutions

This comprehensive review explores the intricate landscape of prone ventilation in the intensive care unit (ICU), spanning physiological rationale, challenges in implementation, psychosocial impacts, technological innovations, economic considerations, barriers to adoption, and implications for clinical practice. The physiological benefits of prone positioning, including improved oxygenation and lung compliance, are discussed alongside the challenges of patient selection and technical complexities. The psychosocial impact on patients and caregivers, as well as the economic implications for healthcare systems, adds a crucial dimension to the analysis. The review also delves into innovative technologies, such as advanced monitoring and automation, shaping the landscape of prone ventilation. Moreover, it addresses the barriers to widespread adoption and outlines strategies to overcome resistance, emphasizing the need for a comprehensive and collaborative approach. The implications for clinical practice underscore the importance of evidence-based guidelines, ongoing education, and a holistic patient-centered care approach. The conclusion highlights the call to action for further research to refine protocols and technology, ultimately optimizing the application of prone ventilation in critical care settings.

Changes in Driving Pressure vs Oxygenation as Predictor of Mortality in Moderate to Severe Acute Respiratory Distress Syndrome Patients Receiving Prone Position Ventilation

Background

Prone position ventilation (PPV) causes improvement in oxygenation, nevertheless, mortality in severe acute respiratory distress syndrome (ARDS) remains high. The changes in the driving pressure (DP) and its role in predicting mortality in moderate to severe ARDS patients receiving PPV is unexplored.

Methods

A prospective observational study, conducted between September 2020 and February 2023 on moderate-severe ARDS patients requiring PPV. The values of DP and oxygenation (ratio of partial pressure of arterial oxygen to fraction of inspired oxygen [PaO2/FiO2]) before, during, and after PPV were recorded. The aim was to compare the DP and oxygenation before, during and after PPV sessions among moderate- severe ARDS patients, and determine the best predictor of mortality.

Results

Total of 52 patients were included; 28-day mortality was 57%. Among the survivors, DP prior to PPV as compared to post-PPV session reduced significantly, from 16.36 ± 2.57 cmH2O to 13.91 ± 1.74 cmH2O (p-value < 0.001), whereas DP did not reduce in the non-survivors (19.43 ± 3.16 to 19.70 ± 3.15 cmH2O (p-value = 0.318)]. Significant improvement in PaO2/FiO2 before PPV to post-PPV among both the survivors [92.75 [67.5-117.75]) to [205.50 (116.25-244.50)], (p-value < 0.001) and also among the non-survivors [87.90 (67.75-100.75)] to [112 (88.00-146.50)], (p-value < 0.001) was noted. Logistic regression analysis showed DP after PPV session as best predictor of mortality (p-value = 0.044) and its AUROC to predict mortality was 0.939, cut-off ≥16 cmH2O, 90% sensitivity, 82% specificity. The Kaplan-Meier curve of DP after PPV ≥16 cmH2O and <16 cmH2O was significant (Log-rank Mantel-Cox p-value < 0.001).

Conclusion

Prone position ventilation-induced decrease in DP is prognostic marker of survival than the increase in PaO2/FiO2. There is a primacy of DP, rather than oxygenation, in predicting mortality in moderate-severe ARDS. Post-PPV session DP ≥16 cmH2O was an independent predictor of mortality.

How to cite this article

Todur P, Nileshwar A, Chaudhuri S, Shanbhag V, Cherisma C. Changes in Driving Pressure vs Oxygenation as Predictor of Mortality in Moderate to Severe Acute Respiratory Distress Syndrome Patients Receiving Prone Position Ventilation. Indian J Crit Care Med 2024;28(2):134-140.

Pressure ulcers after prone positioning in patients undergoing extracorporeal membrane oxygenation: A cross-sectional study

BACKGROUND

The combination of prone positioning and extracorporeal membrane oxygenation (ECMO) in patients with acute respiratory distress syndrome (ARDS) is recognized as safe but its use has been limited due to potential complications.

AIM

To report the prevalence of pressure ulcers and other complications due to prone positioning in adult patients receiving veno-venous ECMO.

STUDY DESIGN

This cross-sectional study was conducted in a tertiary level intensive care unit (ICU) in Milan (Italy), between January 2015 and December 2019. The study population was critically ill adult patients undergoing veno-venous ECMO. Statistical association between pressure ulcers and the type of body positioning (prone versus supine) was explored fitting a logistic model.

RESULTS

In the study period, 114 patients were treated with veno-venous ECMO and 62 (54.4%) patients were placed prone for a total of 130 prone position cycles. ECMO cannulation was performed via femoro-femoral configuration in the majority of patients (82.4%, 94/114). Pressure ulcers developed in 57.0% of patients (95%CI: 44.0%-72.6%), most often arising on the face and the chin (37.1%, 23/62), particularly in those placed prone. The main reason of prone positioning interruption was the decrease of ECMO blood flow (8.1%, 5/62). The fitted model showed no association between body position during ECMO and occurrence of pressure ulcers (OR 1.3, 95%CI: 0.5-3.6, p = .532).

CONCLUSIONS

Facial pressure ulcers were the most frequent complications of prone positioning. Nurses should plan and implement evidence-based care to prevent such pressure injuries in patients undergoing ECMO.

RELEVANCE TO CLINICAL PRACTICE

The combination of prone positioning and ECMO shows few life-threating complications. This manoeuvre during ECMO is feasible and safe when performed by experienced ICU staff.

Reactive Oxygen Species and Strategies for Antioxidant Intervention in Acute Respiratory Distress Syndrome

Acute respiratory distress syndrome (ARDS) is a life-threatening pulmonary condition characterized by the sudden onset of respiratory failure, pulmonary edema, dysfunction of endothelial and epithelial barriers, and the activation of inflammatory cascades. Despite the increasing number of deaths attributed to ARDS, a comprehensive therapeutic approach for managing patients with ARDS remains elusive. To elucidate the pathological mechanisms underlying ARDS, numerous studies have employed various preclinical models, often utilizing lipopolysaccharide as the ARDS inducer. Accumulating evidence emphasizes the pivotal role of reactive oxygen species (ROS) in the pathophysiology of ARDS. Both preclinical and clinical investigations have asserted the potential of antioxidants in ameliorating ARDS. This review focuses on various sources of ROS, including NADPH oxidase, uncoupled endothelial nitric oxide synthase, cytochrome P450, and xanthine oxidase, and provides a comprehensive overview of their roles in ARDS. Additionally, we discuss the potential of using antioxidants as a strategy for treating ARDS.

A single-centre prospective cohort study: prone positioning in awake, non-intubated patients with covid-19 hypoxemic failure

INTRODUCTION

A surge in critically ill patients with respiratory failure due to Covid-19 has overwhelmed ICU capacity in many healthcare systems across the world. Given a guarded prognosis and significant resource limitations, less invasive, inventive approaches such as prone positioning (PP) of non-intubated patients with hypoxemic respiratory failure were considered.

AIMS AND OBJECTIVES

This is a prospective observational study and the aim is to evaluate the impact of awake PP at the ward level on the oxygenation levels of patients with COVID-19. We also are investigating as secondary outcomes, the risk factors for treatment failure among awake non-intubated patients who tolerated PP compared to those who did not. The primary outcome of this trial is the change in SpO2:FiO2 (SF) ratio from admission to discharge in the participants who tolerated PP compared to those that did not. Secondary outcomes included amongst others are ICU admission rate, in-hospital mortality, and length of stay.

METHODS

A total of 63 patients admitted to Beaumont Hospital (BH), Dublin between January and February of 2021 with Covid-19 requiring supplemental oxygen were recruited.

RESULTS

A total of 47 (74%) participants were reported as tolerating and 16 (26%) as non-tolerating PP. The mean rank in the primary endpoint in the tolerating group was 38 vs. 16 in the non-tolerating. This was statistically significant (P < 0.001).

CONCLUSION

PP was associated with improvements in oxygenation parameters without any reported serious adverse events. A well-designed, randomised control trial, testing the efficacy of PP in non-intubated Covid-19 patients is needed, before the widespread adoption of this practice.

Effects of lithotomy and prone positions on hemodynamic parameters, respiratory mechanics, and arterial oxygenation in percutaneous nephrolithotomy performed under general anesthesia

AIM

The position of the body during surgery may affect the patient's body functions, especially the hemodynamic parameters. We aimed to comparatively analyze the effects of lithotomy and prone position on respiratory mechanics, arterial oxygenation, and hemodynamic parameters in patients who underwent percutaneous nephrolithotomy (PNL).

An appraisal of the methodology and quality of evidence of systematic reviews on the efficacy of prone positional ventilation in adult patients with acute respiratory distress syndrome: an umbrella review

The objective of the study was to evaluate all available systematic reviews on the use of prone positional ventilation in adult patients with acute respiratory distress syndrome (ARDS). An umbrella review on the efficacy of prone positional ventilation in adult patients ventilation in adult patients with acute respiratory distress syndrome was conducted. We performed a systematic search in the database of Medline (Pubmed), Scopus, Cochrane Library, Web of Science, and Epistemonikos. The ROBIS tools and GRADE methodology were used to assess the risk of bias and certainty of evidence. We estimated the necessary number of patients to be treated to have benefit. For the synthesis of the result, we selected the review with the lowest risk of bias. Sixteen systematic reviews including 64 randomized clinical trials and evaluating the effect of prone positional ventilation, with or without other ventilation strategies were included. Aoyama 2019 observed prone positioning, without complementary ventilation strategies, leading to a reduction in the 28-day mortality only when compared to high-frequency oscillatory ventilation (RR 0.61; 95% CI 0.39-0.95) and lung-protective ventilation in the supine position (RR 0.69; 95% CI 0.48-0.98), with an ARR of 9.32% and 14.94%, an NNTB of 5.89 and 8.04, and a low and moderate certainty of evidence, respectively. Most reviews had severe methodological flaws that led to results with very low certainty of evidence. The review with the lowest risk of bias presented results in favor of prone positional ventilation compared with high-frequency oscillatory ventilation and lung-protective ventilation. There is a need to update the available reviews to obtain more accurate results.

Regional ventilation in spontaneously breathing COVID-19 patients during postural maneuvers assessed by electrical impedance tomography

BACKGROUND

Gravity-dependent positioning therapy is an established concept in the treatment of severe acute respiratory distress syndrome and improves oxygenation in spontaneously breathing patients with hypoxemic acute respiratory failure. In patients with coronavirus disease 2019, this therapy seems to be less effective. Electrical impedance tomography as a point-of-care functional imaging modality for visualizing regional ventilation can possibly help identify patients who might benefit from positioning therapy and guide those maneuvers in real-time. Therefore, in this prospective observational study, we aimed to discover typical patterns in response to positioning maneuvers.

METHODS

Distribution of ventilation in 10 healthy volunteers and in 12 patients with hypoxemic respiratory failure due to coronavirus disease 2019 was measured in supine, left, and right lateral positions using electrical impedance tomography.

RESULTS

In this study, patients with coronavirus disease 2019 showed a variety of ventilation patterns, which were not predictable, whereas all but one healthy volunteer showed a typical and expected gravity-dependent distribution of ventilation with the body positions.

CONCLUSION

Distribution of ventilation and response to lateral positioning is variable and thus unpredictable in spontaneously breathing patients with coronavirus disease 2019. Electrical impedance tomography might add useful information on the immediate reaction to postural maneuvers and should be elucidated further in clinical studies. Therefore, we suggest a customized individualized positioning therapy guided by electrical impedance tomography.

Management of refractory hypoxemia using recruitment maneuvers and rescue therapies: A comprehensive review

Refractory hypoxemia in patients with acute respiratory distress syndrome treated with mechanical ventilation is one of the most challenging conditions in human and veterinary intensive care units. When a conventional lung protective approach fails to restore adequate oxygenation to the patient, the use of recruitment maneuvers and positive end-expiratory pressure to maximize alveolar recruitment, improve gas exchange and respiratory mechanics, while reducing the risk of ventilator-induced lung injury has been suggested in people as the open lung approach. Although the proposed physiological rationale of opening and keeping open previously collapsed or obstructed airways is sound, the technique for doing so, as well as the potential benefits regarding patient outcome are highly controversial in light of recent randomized controlled trials. Moreover, a variety of alternative therapies that provide even less robust evidence have been investigated, including prone positioning, neuromuscular blockade, inhaled pulmonary vasodilators, extracorporeal membrane oxygenation, and unconventional ventilatory modes such as airway pressure release ventilation. With the exception of prone positioning, these modalities are limited by their own balance of risks and benefits, which can be significantly influenced by the practitioner's experience. This review explores the rationale, evidence, advantages and disadvantages of each of these therapies as well as available methods to identify suitable candidates for recruitment maneuvers, with a summary on their application in veterinary medicine. Undoubtedly, the heterogeneous and evolving nature of acute respiratory distress syndrome and individual lung phenotypes call for a personalized approach using new non-invasive bedside assessment tools, such as electrical impedance tomography, lung ultrasound, and the recruitment-to-inflation ratio to assess lung recruitability. Data available in human medicine provide valuable insights that could, and should, be used to improve the management of veterinary patients with severe respiratory failure with respect to their intrinsic anatomy and physiology.

Changes in infant porcine pulmonary tissue oxylipins induced by cardiopulmonary bypass

BACKGROUND

Oxylipins are metabolites derived from fatty acids such as arachidonic acid (AA) and are key mediators in inflammation, host defense, and tissue injury. Serum oxylipins increase in adults after cardiopulmonary bypass (CPB) but tissue-level changes are poorly defined. The objective of this study was to characterize pulmonary tissue oxylipins in an infant porcine model of CPB with deep hypothermic circulatory arrest (DHCA).

METHODS

Infant pigs underwent CPB with DHCA. Controls received anesthesia only. Right upper and lower lobes of the lung underwent oxylipin analysis via liquid chromatography-tandem mass spectrometry. One-way ANOVA was utilized to assess differences in oxylipin concentrations across groups, followed by pairwise comparisons.

RESULTS

AA and multiple AA metabolites via cytochrome P450 (CYP450), lipoxygenase (LOX), and cyclooxygenase (COX) pathways were significantly increased in the upper and lower lobe of pigs exposed to CPB/DHCA as compared to controls. Multiple prostaglandin metabolites produced via COX were also significantly elevated in the lower lobes of control animals.

CONCLUSIONS

CPB/DHCA induces a significant increase in pulmonary tissue AA, with subsequent metabolism via COX, LOX, and CYP450 pathways. Interestingly, prostaglandins were also elevated in the lower lobes of the controls, suggesting a mechanism separate from CPB/DHCA. Future oxylipin studies are needed to better understand CPB-induced acute lung injury.

IMPACT

CPB/DHCA and, to a lesser extent, lung region influence pulmonary tissue-level AA metabolite production. Inflammatory mediator AA metabolites have been noted in previous studies to increase following CPB; however, this is the first study to look at pulmonary tissue-level differences following CPB/DHCA. Increases in many AA metabolites, including LOX- and CYP450-derived products, were seen in both upper and lower lobe of piglets following CPB/DHCA. COX-derived prostaglandin metabolites were increased not only in CPB upper and lower lobe but also in mechanically ventilated control lower lobe, suggesting an additional, separate mechanism from CPB/DCHA.

Positioning for acute respiratory distress in hospitalised infants and children

BACKGROUND

Acute respiratory distress syndrome (ARDS) is a significant cause of hospitalisation and death in young children. Positioning and mechanical ventilation have been regularly used to reduce respiratory distress and improve oxygenation in hospitalised patients. Due to the association of prone positioning (lying on the abdomen) with sudden infant death syndrome (SIDS) within the first six months, it is recommended that young infants be placed on their back (supine). However, prone positioning may be a non-invasive way of increasing oxygenation in individuals with acute respiratory distress, and offers a more significant survival advantage in those who are mechanically ventilated. There are substantial differences in respiratory mechanics between adults and infants. While the respiratory tract undergoes significant development within the first two years of life, differences in airway physiology between adults and children become less prominent by six to eight years old. However, there is a reduced risk of SIDS during artificial ventilation in hospitalised infants. Thus, an updated review focusing on positioning for infants and young children with ARDS is warranted. This is an update of a review published in 2005, 2009, and 2012.

OBJECTIVES

To compare the effects of different body positions in hospitalised infants and children with acute respiratory distress syndrome aged between four weeks and 16 years.

SEARCH METHODS

We searched CENTRAL, which contains the Acute Respiratory Infections Group's Specialised Register, MEDLINE, Embase, and CINAHL from January 2004 to July 2021.

SELECTION CRITERIA

Randomised controlled trials (RCTs) or quasi-RCTs comparing two or more positions for the management of infants and children hospitalised with ARDS.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data from each study. We resolved differences by consensus, or referred to a third contributor to arbitrate. We analysed bivariate outcomes using an odds ratio (OR) and 95% confidence interval (CI). We analysed continuous outcomes using a mean difference (MD) and 95% CI. We used a fixed-effect model, unless heterogeneity was significant (I² statistic > 50%), when we used a random-effects model.

MAIN RESULTS

We included six trials: four cross-over trials, and two parallel randomised trials, with 198 participants aged between 4 weeks and 16 years, all but 15 of whom were mechanically ventilated. Four trials compared prone to supine positions. One trial compared the prone position to good-lung dependent (where the person lies on the side of the healthy lung, e.g. if the right lung was healthy, they were made to lie on the right side), and independent (or non-good-lung independent, where the person lies on the opposite side to the healthy lung, e.g. if the right lung was healthy, they were made to lie on the left side) position. One trial compared good-lung independent to good-lung dependent positions. When the prone (with ventilators) and supine positions were compared, there was no information on episodes of apnoea or mortality due to respiratory events. There was no conclusive result in oxygen saturation (SaO_2; MD 0.40 mmHg, 95% CI -1.22 to 2.66; 1 trial, 30 participants; very low certainty evidence); blood gases, PCO₂ (MD 3.0 mmHg, 95% CI -1.93 to 7.93; 1 trial, 99 participants; low certainty evidence), or PO₂ (MD 2 mmHg, 95% CI -5.29 to 9.29; 1 trial, 99 participants; low certainty evidence); or lung function (PaO₂/FiO₂ ratio; MD 28.16 mmHg, 95% CI -9.92 to 66.24; 2 trials, 121 participants; very low certainty evidence). However, there was an improvement in oxygenation index (FiO₂% X M_PAW/ PaO₂) with prone positioning in both the parallel trials (MD -2.42, 95% CI -3.60 to -1.25; 2 trials, 121 participants; very low certainty evidence), and the cross-over study (MD -8.13, 95% CI -15.01 to -1.25; 1 study, 20 participants). Derived indices of respiratory mechanics, such as tidal volume, respiratory rate, and positive end-expiratory pressure (PEEP) were reported. There was an apparent decrease in tidal volume between prone and supine groups in a parallel study (MD -0.60, 95% CI -1.05 to -0.15; 1 study, 84 participants; very low certainty evidence). When prone and supine positions were compared in a cross-over study, there were no conclusive results in respiratory compliance (MD 0.07, 95% CI -0.10 to 0.24; 1 study, 10 participants); changes in PEEP (MD -0.70 cm H₂O, 95% CI -2.72 to 1.32; 1 study, 10 participants); or resistance (MD -0.00, 95% CI -0.05 to 0.04; 1 study, 10 participants). One study reported adverse events. There were no conclusive results for potential harm between groups in extubation (OR 0.57, 95% CI 0.13 to 2.54; 1 trial, 102 participants; very low certainty evidence); obstructions of the endotracheal tube (OR 5.20, 95% CI 0.24 to 111.09; 1 trial, 102 participants; very low certainty evidence); pressure ulcers (OR 1.00, 95% CI 0.41 to 2.44; 1 trial, 102 participants; very low certainty evidence); and hypercapnia (high levels of arterial carbon dioxide; OR 3.06, 95% CI 0.12 to 76.88; 1 trial, 102 participants; very low certainty evidence). One study (50 participants) compared supine positions to good-lung dependent and independent positions. There was no conclusive evidence that PaO₂ was different between supine and good-lung dependent positioning (MD 3.44 mm Hg, 95% CI -23.12 to 30.00; 1 trial, 25 participants; very low certainty evidence). There was also no conclusive evidence for supine position and good-lung independent positioning (MD -2.78 mmHg, 95% CI -28.84, 23.28; 25 participants; very low certainty evidence); or between good-lung dependent and independent positioning (MD 6.22, 95% CI -21.25 to 33.69; 1 trial, 25 participants; very low certainty evidence). As most trials did not describe how possible biases were addressed, the potential for bias in these findings is unclear.

AUTHORS' CONCLUSIONS

Although included studies suggest that prone positioning may offer some advantage, there was little evidence to make definitive recommendations. There appears to be low certainty evidence that positioning improves oxygenation in mechanically ventilated children with ARDS. Due to the increased risk of SIDS with prone positioning and lung injury with artificial ventilation, it is recommended that hospitalised infants and children should only be placed in this position while under continuous cardiorespiratory monitoring.

Effectiveness of prone position in acute respiratory distress syndrome and moderating factors of obesity class and treatment durations for COVID-19 patients: A Meta-Analysis

Objectives

To examine the effectiveness of prone positioning on COVID-19 patients with acute respiratory distress syndrome with moderating factors in both traditional prone positioning (invasive mechanical ventilation) and awake self-prone positioning patients (non-invasive ventilation).

Research methodology

A comprehensive search was conducted in CINAHL, Cochrane library, Embase, Medline-OVID, NCBI SARS-CoV-2 Resources, ProQuest, Scopus, and Web of Science without language restrictions. All studies with prospective and experimental designs evaluating the effect of prone position patients with COVID-19 related to acute respiratory distress syndrome were included. Pooled standardised mean differences were calculated after prone position for primary (PaO₂/FiO₂) and secondary outcomes (SpO₂ and PaO₂)

Results

A total of 15 articles were eligible and included in the final analysis. Prone position had a statistically significant effect in improving PaO₂/FiO₂ with standardised mean difference of 1.10 (95%CI 0.60–1.59), SpO₂ with standardised mean difference of 3.39 (95% CI 1.30–5.48), and PaO₂ with standardised mean difference of 0.77 (95% CI 0.19–1.35). Patients with higher body mass index and longer duration/day are associated with larger standardised mean difference effect sizes for prone positioning.

Conclusions

Our findings demonstrate that prone position significantly improved oxygen saturation in COVID-19 patients with acute respiratory distress syndrome in both traditional prone positioning and awake self-prone positioning patients. Prone position should be recommended for patients with higher body mass index and longer durations to obtain the maximum effect.

Proning modus operandi in pregnancies complicated by acute respiratory distress syndrome secondary to COVID-19

INTRODUCTION

Prone positioning has been widely utilized in ARDS management before and during the COVID-19 pandemic due to its demonstrated mortality benefits. In pregnancy, proning requires careful attention to often overlooked physiologic changes in pregnancy and additional technical challenges accompanying a gravid abdomen. The purpose of this manuscript is to demonstrate a proning technique that was successfully used at our institution to avoid premature delivery of the fetus while improving maternal outcomes. All technical challenges are addressed in the instructional videos using a pregnant model with twin gestation at 32 weeks.

METHODS

We reviewed all the patients' charts with positive SARS-CoV-2 from March 2020 until July 2020 and identified those who developed ARDS. Subsequently, we identified four patients that were proned during the antepartum period. We described their clinical course, including the change in ventilatory parameters in relationship with proning timing. Stepwise instructions for self-proning and proning in mechanically ventilated patients are illustrated in video format.

RESULTS

During the study period, we identified 100 pregnant patients with SARS-CoV-2 infection. Mechanical ventilation was required in 8 of these patients. In four cases, proning was performed during the antepartum period. We were able to improve the P/F ratio while decreasing FiO₂ and avoiding iatrogenic preterm delivery. Except for one case, where the patient self-extubated and required emergent delivery, all patients were successfully extubated, followed for prenatal care, and delivered for usual obstetric indications.

CONCLUSION

Proning remains a well-proven intervention in ARDS and should be considered in pregnant women when indicated. We recognize that proning might not be effective in all cases. However, proning positioning is an option to improve oxygenation in patients with severe hypoxemia when the next consideration is delivery of a premature infant or maternal cannulation for extracorporeal membrane oxygenation.

Implementation and Assessment of a Proning Protocol for Nonintubated Patients With COVID-19

INTRODUCTION

The COVID-19 pandemic has caused over 1,250,000 deaths worldwide. With limited therapeutic options, proning nonintubated patients emerged as a safe and affordable intervention to manage hypoxemia.

METHODS

A proning protocol to identify and prone eligible patients was implemented. Patients were encouraged to self-prone for 2-3 hours, 3 times daily. Investigators created educational materials for nurses and patients and developed a COVID-19-specific proning order within the electronic health record (EHR). Investigators completed an 800-person retrospective chart review to study the implementation of this protocol.

RESULTS

From March 22, 2020, to June 5, 2020, 586 patients were admitted to the COVID-19 floor. Of these patients, 42.8% were eligible for proning. Common contraindications were lack of hypoxia, altered mental status, and fall risk. The proning protocol led to a significant improvement in provider awareness of patients appropriate for proning, increasing from 12% to 83%, as measured by placement of a proning order into the EHR. There was a significant improvement in all appropriate patients documented as proned, increasing from 18% to 45% of eligible patients.

CONCLUSIONS

The creation of an effective hospital-wide proning protocol to address the exigencies of the COVID-19 pandemic is possible and may be accomplished in a short period of time.

The prone position ventilation (PPV) as an approach in pregnancy with acute respiratory distress syndrome (ARDS)

Objective

In Taiwan, the overall incidence of acute respiratory distress syndrome (ARDS) is 15.74 per 100,000 person-years, the mortality rate is 57.8%, and its overall prevalence in the intensive care unit (ICU) is 10.4%. Women who are pregnant and have ARDS have a high risk of fetal death and fetal asphyxia.

Case report

A 26-1/7-week pregnant woman presented with upper respiratory infection symptoms progressing to ARDS. While receiving ventilation, maintaining a prone position is an option for pregnant patients with severe ARDS. This case demonstrated a supplementary approach for pregnant women with ARDS.

Conclusion

Prone position ventilation is indicated for pregnant women, as for any patient with ARDS. The Proning Severe ARDS Patients trial showed no difference in the complication between pregnant patients and other groups.

Evaluation of Adjunctive Photobiomodulation (PBMT) for COVID-19 Pneumonia via Clinical Status and Pulmonary Severity Indices in a Preliminary Trial

PURPOSE

Evidence-based and effective treatments for COVID-19 are limited, and a new wave of infections and deaths calls for novel, easily implemented treatment strategies. Photobiomodulation therapy (PBMT) is a well-known adjunctive treatment for pain management, wound healing, lymphedema, and cellulitis. PBMT uses light to start a cascade of photochemical reactions that lead to local and systemic anti-inflammatory effects at multiple levels and that stimulate healing. Numerous empirical studies of PBMT for patients with pulmonary disease such as pneumonia, COPD and asthma suggest that PBMT is a safe and effective adjunctive treatment. Recent systematic reviews suggest that PBMT may be applied to target lung tissue in COVID-19 patients. In this preliminary study, we evaluated the effect of adjunctive PBMT on COVID-19 pneumonia and patient clinical status.

PATIENTS AND METHODS

We present a small-scale clinical trial with 10 patients randomized to standard medical care or standard medical care plus adjunctive PBMT. The PBMT group received four daily sessions of near-infrared light treatment targeting the lung tissue via a Multiwave Locked System (MLS) laser. Patient outcomes were measured via blood work, chest x-rays, pulse oximetry and validated scoring tools for pneumonia.

RESULTS

PBMT patients showed improvement on pulmonary indices such as SMART-COP, BCRSS, RALE, and CAP (Community-Acquired Pneumonia questionnaire). PBMT-treated patients showed rapid recovery, did not require ICU admission or mechanical ventilation, and reported no long-term sequelae at 5 months after treatment. In the control group, 60% of patients were admitted to the ICU for mechanical ventilation. The control group had an overall mortality of 40%. At a 5-month follow-up, 40% of the control group experienced long-term sequelae.

CONCLUSION

PBMT is a safe and effective potential treatment for COVID-19 pneumonia and improves clinical status in COVID-19 pneumonia.

Role of awake prone positioning in patients with moderate-to-severe COVID-19: an experience from a developing country

There is limited evidence on the efficacy of awake prone positioning (PP) in non-ventilated patients with COVID-19 who have hypoxemia. We, therefore, aim to describe our experience with the use of early proning in awake, non-intubated patients with confirmed COVID-19. In our retrospective observational study, 23 patients with confirmed positive PCR test results for Severe Acute respiratory Syndrome Coronavirus-2 (SARS-CoV-2) and hypoxemia that required oxygen therapy with or without non-invasive ventilation were treated with PP. Patients were classified into mild, moderate and severe COVID-19 disease. There were no targeted number of hours for proning per day and patients were kept in prone position according to their tolerance. The primary outcome measure was the avoidance of intubation and secondary outcomes were in-hospital mortality, length of hospital stays and complications related to PP. The mean (standard deviation) age of our cohort was 54.5 (11.7) years, and the majority were males (21/23, 91.3%). Sixty-one per cent (14/23) of the patients were suffering from severe disease and 82.6% (19/23) had bilateral lung involvement with interstitial infiltrates. Majority of the patients were prone positioned for a median of 6 days (IQR 4 - 8). Only one patient required transfer to ICU for mechanical ventilation and subsequently died due to severe ARDS. All 22 patients showed progressive improvement in oxygen requirement and PF ratio, mostly after 3-5 days of proning. The mean length of hospital stay was 12 days. All patients, except one, were discharged in stable conditions, on room air or on a minimal oxygen requirement of 1-2 liters. No major complication of PP was recorded. Awake prone positioning is a valuable and safe therapeutic adjunct that can be applied in patients with moderate-to-severe COVID-19. It can also be included in the home-based management protocols of COVID-19 to improve patient outcomes and mitigate the burden on health care facilities.

Use of dexamethasone, remdesivir, convalescent plasma and prone positioning in the treatment of severe COVID-19 infection in pregnancy: A case report

Severe infection with COVID-19 virus in pregnancy offers unique management challenges for the obstetrician and critical care specialist. We report the case of a woman at 26 weeks of gestation with acute respiratory distress syndrome secondary to COVID-19 infection treated with dexamethasone, remdesivir, convalescent plasma and mechanical ventilation. Cesarean delivery was performed at 29 weeks due to worsening maternal status. This case offers insight into the assessment and successful use of treatment strategies, including dexamethasone, remdesivir, convalescent plasma, early prone positioning, conservative fluid management, permissive hypoxia and low tidal volume parameters with ventilator support for pregnancies affected by severe COVID-19 infection.

Review and Analysis of Massively Registered Clinical Trials of COVID-19 using the Text Mining Approach

OBJECTIVE

Immediately after the outbreak of nCoV, many clinical trials are registered for COVID-19. The numbers of registrations are now raising inordinately. It is challenging to understand which research areas are explored in this massive pool of clinical studies. If such information can be compiled, then it is easy to explore new research studies for possible contributions in COVID-19 research.

METHODS

In the present work, a text-mining technique of artificial intelligence is utilized to map the research domains explored through the clinical trials of COVID-19. With the help of the open-- source and graphical user interface-based tool, 3007 clinical trials are analyzed here. The dataset is acquired from the international clinical trial registry platform of WHO. With the help of hierarchical cluster analysis, the clinical trials were grouped according to their common research studies. These clusters are analyzed manually using their word clouds for understanding the scientific area of a particular cluster. The scientific fields of clinical studies are comprehensively reviewed and discussed based on this analysis.

RESULTS

More than three-thousand clinical trials are grouped in 212 clusters by hierarchical cluster analysis. Manual intervention of these clusters using their individual word-cloud helped to identify various scientific areas which are explored in COVID19 related clinical studies.

CONCLUSION

The text-mining is an easy and fastest way to explore many registered clinical trials. In our study, thirteen major clusters or research areas were identified in which the majority of clinical trials were registered. Many other uncategorized clinical studies were also identified as "miscellaneous studies". The clinical trials within the individual cluster were studied, and their research purposes are compiled comprehensively in the present work.

Responsiveness of Inhaled Epoprostenol in Respiratory Failure due to COVID-19

BACKGROUND

Inhaled pulmonary vasodilators are used as adjunctive therapies for the treatment of refractory hypoxemia. Available evidence suggest they improve oxygenation in a subset of patients without changing long-term trajectory. Given the differences in respiratory failure due to COVID-19 and "traditional" ARDS, we sought to identify their physiologic impact.

METHODS

This is a retrospective observational study of patients mechanically ventilated for COVID-19, from the ICUs of 2 tertiary care centers, who received inhaled epoprostenol (iEpo) for the management of hypoxemia. The primary outcome is change in PaO₂/FiO₂. Additionally, we measured several patient level features to predict iEpo responsiveness (or lack thereof).

RESULTS

Eighty patients with laboratory confirmed SARS-CoV2 received iEpo while mechanically ventilated and had PaO₂/FiO₂ measured before and after. The median PaO₂/FiO₂ prior to receiving iEpo was 92 mmHg and interquartile range (74 - 122). The median change in PaO₂/FiO₂ was 9 mmHg (-9 - 37) corresponding to a 10% improvement (-8 - 41). Fifty-percent (40 / 80) met our a priori definition of a clinically significant improvement in PaO₂/FiO₂ (increase in 10% from the baseline value). Prone position and lower PaO₂/FiO₂ when iEpo was started predicted a more robust response, which held after multivariate adjustment. For proned individuals, improvement in PaO₂/FiO₂ was 14 mmHg (-6 to 45) vs. 3 mmHg (-11 - 20), p = 0.04 for supine individuals; for those with severe ARDS (PaO₂/FiO₂ < 100, n = 49) the median improvement was 16 mmHg (-2 - 46).

CONCLUSION

Fifty percent of patients have a clinically significant improvement in PaO₂/FiO₂ after the initiation of iEpo. This suggests it is worth trying as a rescue therapy; although generally the benefit was modest with a wide variability. Those who were prone and had lower PaO₂/FiO₂ were more likely to respond.

Focus, Not Point-of-Care, Echocardiography in Prone Position: It Can Be Done in COVID-19 Patients

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Prone positioning improves oxygenation in patients with ARDS.

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Reducing RV dysfunction is vital to decrease mortality.

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Prone positioning may assist cardiac function by offloading pressure from the RV.

A 57-Year-Old African American Man with Severe COVID-19 Pneumonia Who Responded to Supportive Photobiomodulation Therapy (PBMT): First Use of PBMT in COVID-19

Patient: Male, 57-year-old

Final Diagnosis: COVID-19

Symptoms: Shortness of breath • hypoxia

Medication: —

Clinical Procedure: Photobiomodulation therapy (PBMT)

Specialty: Infectious Diseases • Pulmonology

Protecting prone positioned patients from facial pressure ulcers using prophylactic dressings: A timely biomechanical analysis in the context of the COVID-19 pandemic

Prone positioning is used for surgical access and recently in exponentially growing numbers of coronavirus disease 2019 patients who are ventilated prone. To reduce their facial pressure ulcer risk, prophylactic dressings can be used; however, the biomechanical efficacy of this intervention has not been studied yet. We, therefore, evaluated facial soft tissue exposures to sustained mechanical loads in a prone position, with versus without multi‐layered silicone foam dressings applied as tissue protectors at the forehead and chin. We used an anatomically realistic validated finite element model of an adult male head to determine the contribution of the dressings to the alleviation of the sustained tissue loads. The application of the dressings considerably relieved the tissue exposures to loading. Specifically, with respect to the forehead, the application of a dressing resulted in 52% and 71% reductions in soft tissue exposures to effective stresses and strain energy densities, respectively. Likewise, a chin dressing lowered the soft tissue exposures to stresses and strain energy densities by 78% and 92%, respectively. While the surgical context is clear and there is a solid, relevant need for biomechanical information regarding prophylaxis for the prone positions, the projected consequences of the coronavirus pandemic make the present work more relevant than ever before.

Shedding Light on Dysphagia Associated With COVID-19: The What and Why

The most common symptom of COVID-19 in critically ill patients is ARDS (acute respiratory distress syndrome), with many patients requiring invasive or noninvasive respiratory support in the intensive care unit. Oropharyngeal dysphagia may be a consequence of the respiratory-swallowing incoordination common in ARDS or may occur following the respiratory support interventions. In this commentary, we highlight the risk and complications of oropharyngeal dysphagia in patients with COVID-19 and urge medical and rehabilitation professionals to consider dysphagia a prognostic complication, provide appropriate referrals, and initiate early interventions as appropriate.

Turning Things Around: The Role of Prone Positioning in the Management of Acute Respiratory Failure After Cardiac Surgery

OBJECTIVES

The aim of this study was to determine the benefit of prone positioning (PP) in patients developing acute respiratory failure (ARF) after cardiac surgery.

DESIGN

A retrospective analysis.

SETTING

Review of the institutional database between October 2016 and October 2018 revealed 24 patients who underwent PP for the treatment of ARF after cardiac surgery.

PARTICIPANTS

The authors found 24 patients who underwent PP for the treatment of ARF after cardiac surgery. This included 10 patients who required extracorporeal membrane oxygenation (ECMO) therapy. Among them, 6 patients with simultaneous PP and ECMO therapy.

INTERVENTIONS

Data were collected at the time of PP, 6 hours after PP, at the end of PP, and 6 hours after return to supine position (SP).

MEASUREMENTS AND MAIN RESULTS

The median duration of postoperative mechanical ventilation was 281 hours (183-528 hours). Prone positioning was carried out on the fourth postoperative day (POD), with a total of 5 patients undergoing PP within 24 hours following surgery. The median duration of PP before return to SP was 12 hours (12-16 hours), with the maximal duration of PP being 22 hours in this cohort. The authors observed an increase in Horowitz index (HI) at the end of PP (p < 0.001) as well as 6 hours after supine positioning. In the subgroup of patients who underwent PP on ECMO (v-a ECLS = 3, v-v ECMO = 3), a significant reduction of ECMO support was achieved from 3.0 (2.2-5.6) liters/min to 2.5 (2.0-4.6) liters/min (p = 0.023). No adverse events occurred during the positioning of the patients.

CONCLUSIONS

Prone positioning can be considered for the treatment of ARF after cardiac surgery to improve short-term respiratory conditions and possibly facilitate ECMO weaning.

Free-breathing quantification of regional ventilation derived by phase-resolved functional lung (PREFUL) MRI

PURPOSE

To test the feasibility of regional fully quantitative ventilation measurement in free breathing derived by phase-resolved functional lung (PREFUL) MRI in the supine and prone positions. In addition, the influence of T₂ * relaxation time on ventilation quantification is assessed.

METHODS

Twelve healthy volunteers underwent functional MRI at 1.5 T using a 2D triple-echo spoiled gradient echo sequence allowing for quantitative measurement of T₂ * relaxation time. Minute ventilation (ΔV) was quantified by conventional fractional ventilation (FV) and the newly introduced regional ventilation (VR), which corrects volume errors due to image registration. ΔV_FV versus ΔV_VR and ΔV_VR versus ΔV_VR with T₂ * correction were compared using Bland-Altman plots and correlation analysis. The repeatability and physiological plausibility of all measurements were tested in the supine and prone positions.

RESULTS

On global and regional scales a strong correlation was observed between ΔV_FV versus ΔV_VR and ΔV_VR versus ΔV_VRT2* (r > 0.93); however, regional Bland-Altman analysis showed systematic differences (p < 0.0001). Unlike ΔV_VRT2* , ΔV_VR and ΔV_FV showed expected physiologic anterior-posterior gradients, which decreased in the supine but not in the prone position at second measurement during 3 min in the same position. For all quantification methods a moderate repeatability (coefficient of variation <20%) of ventilation was found.

CONCLUSION

A fully quantified regional ventilation measurement using ΔV_VR in free breathing is feasible and shows physiologically plausible results. In contrast to conventional ΔV_FV, volume errors due to image registration are eliminated with the ΔV_VR approach. However, correction for the T₂ * effect remains challenging.

Capturing complexity in pulmonary system modelling

Respiratory disease is a significant problem worldwide, and it is a problem with increasing prevalence. Pathology in the upper airways and lung is very difficult to diagnose and treat, as response to disease is often heterogeneous across patients. Computational models have long been used to help understand respiratory function, and these models have evolved alongside increases in the resolution of medical imaging and increased capability of functional imaging, advances in biological knowledge, mathematical techniques and computational power. The benefits of increasingly complex and realistic geometric and biophysical models of the respiratory system are that they are able to capture heterogeneity in patient response to disease and predict emergent function across spatial scales from the delicate alveolar structures to the whole organ level. However, with increasing complexity, models become harder to solve and in some cases harder to validate, which can reduce their impact clinically. Here, we review the evolution of complexity in computational models of the respiratory system, including successes in translation of models into the clinical arena. We also highlight major challenges in modelling the respiratory system, while making use of the evolving functional data that are available for model parameterisation and testing.