Prone positioning of patients with acute respiratory distress syndrome: a systematic review

Pulmonary Specific Ancillary Treatment for Pediatric Acute Respiratory Distress Syndrome: From the Second Pediatric Acute Lung Injury Consensus Conference

OBJECTIVES

We conducted an updated review of the literature on pulmonary-specific ancillary therapies for pediatric acute respiratory distress syndrome (PARDS) to provide an update to the Pediatric Acute Lung Injury Consensus Conference recommendations and statements about clinical practice and research.

DATA SOURCES

MEDLINE (Ovid), Embase (Elsevier), and CINAHL Complete (EBSCOhost).

STUDY SELECTION

Searches were limited to children, PARDS or hypoxic respiratory failure and overlap with pulmonary-specific ancillary therapies.

DATA EXTRACTION

Title/abstract review, full-text review, and data extraction using a standardized data collection form.

DATA SYNTHESIS

The Grading of Recommendations Assessment, Development, and Evaluation approach was used to identify and summarize evidence and develop recommendations. Twenty-six studies were identified for full-text extraction. Four clinical recommendations were generated, related to use of inhaled nitric oxide, surfactant, prone positioning, and corticosteroids. Two good practice statements were generated on the use of routine endotracheal suctioning and installation of isotonic saline prior to endotracheal suctioning. Three research statements were generated related to: the use of open versus closed suctioning, specific methods of airway clearance, and various other ancillary therapies.

CONCLUSIONS

The evidence to support or refute any of the specific ancillary therapies in children with PARDS remains low. Further investigation, including a focus on specific subpopulations, is needed to better understand the role, if any, of these various ancillary therapies in PARDS.

Facial Pressure Sores in COVID-19 Patients during Prone Positioning: A Case Series and Literature Review

COVID-19 has been a source of several stays in intensive care units, increasing the number of prone positioning. In parallel, complications increased, such as facial ulcers. Herein, we present a literature review and a case series about facial pressure sores in COVID-19 patients during prone positioning. This study aimed to show that such facial pressure sores may require surgical intervention in specific cases.

Upper Extremity Monoplegia following Prone Surrender Position for Spinal Surgery

Background Secondary peripheral nerve injuries remain a significant perioperative problem due to patient positioning and contribute to reduced patient quality of life and exacerbated professional liability. Comorbidities and concomitant lesions can further elicit these injuries in patients undergoing spinal surgeries.

Case Presentation We report a case of a 70-year-old male polytrauma patient presenting with a left first-rib fracture and an adjacent hematoma around the brachial plexus without preoperative deficits. Subsequent to a lumbar spinal fusion in the prone position, he developed a postoperative left upper extremity monoplegia. The postoperative magnetic resonance imaging revealed an enhanced asymmetric signal in the trunks and cords of the left brachial plexus. He progressively improved with rehabilitation, a year after the initial presentation, with a residual wrist drop.

Conclusions Pan brachial plexus monoplegia, following spine surgery, is rare and under-reported pathology. To minimize the occurrence of this rare morbidity, appropriate considerations in preoperative evaluation and counseling, patient positioning, intraoperative anesthetic, and electrophysiological monitoring should be performed. We emphasize an unreported risk factor in polytrauma patients, predisposing this rare injury that is associated with prone spinal surgery positioning, SEPs being an extremely sensitive test intraoperatively and highlight the importance of counseling patients and families to the possibility of this rare occurrence.

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.

Respiratory Physiology of Prone Positioning With and Without Inhaled Nitric Oxide Across the Coronavirus Disease 2019 Acute Respiratory Distress Syndrome Severity Spectrum

Supplemental Digital Content is available in the text.

IMPORTANCE:

Prone positioning improves clinical outcomes in moderate-to-severe acute respiratory distress syndrome and has been widely adopted for the treatment of patients with acute respiratory distress syndrome due to coronavirus disease 2019. Little is known about the effects of prone positioning among patients with less severe acute respiratory distress syndrome, obesity, or those treated with pulmonary vasodilators.

OBJECTIVES:

We characterize the change in oxygenation, respiratory system compliance, and dead-space-to-tidal-volume ratio in response to prone positioning in patients with coronavirus disease 2019 acute respiratory distress syndrome with a range of severities. A subset analysis of patients treated with inhaled nitric oxide and subsequent prone positioning explored the influence of pulmonary vasodilation on the physiology of prone positioning.

DESIGN, SETTING, AND PARTICIPANTS:

Retrospective cohort study of all consecutively admitted adult patients with acute respiratory distress syndrome due to coronavirus disease 2019 treated with mechanical ventilation and prone positioning in the ICUs of an academic hospital between March 11, 2020, and May 1, 2020.

MAIN OUTCOMES AND MEASURES:

Respiratory system mechanics and gas exchange during the first episode of prone positioning.

RESULTS:

Among 122 patients, median (interquartile range) age was 60 years (51–71 yr), median body mass index was 31.5 kg/m² (27–35 kg/m²), and 50 patients (41%) were female. The ratio of Pao₂ to Fio₂ improved with prone positioning in 90% of patients. Prone positioning was associated with a significant increase in the ratio of Pao₂ to Fio₂ (from median 149 [123–170] to 226 [169–268], p < 0.001) but no change in dead-space-to-tidal-volume ratio or respiratory system compliance. Supine ratio of Pao₂ to Fio₂, respiratory system compliance, positive end-expiratory pressure, and body mass index did not correlate with absolute change in the ratio of Pao₂ to Fio₂ with prone positioning. However, patients with ratio of Pao₂ to Fio₂ less than 150 experienced a greater relative improvement in oxygenation with prone positioning than patients with ratio of Pao₂ to Fio₂ greater than or equal to 150 (median percent change in ratio of Pao₂ to Fio₂ 62 [29–107] vs 30 [10–70], p = 0.002). Among 12 patients, inhaled nitric oxide prior to prone positioning was associated with a significant increase in the ratio of Pao₂ to Fio₂ (from median 136 [77–168] to 170 [138–213], p = 0.003) and decrease in dead-space-to-tidal-volume ratio (0.54 [0.49–0.58] to 0.46 [0.44–0.53], p = 0.001). Subsequent prone positioning in this subgroup further improved the ratio of Pao₂ to Fio₂ (from 145 [122–183] to 205 [150–232], p = 0.017) but did not change dead-space-to-tidal-volume ratio.

CONCLUSIONS AND RELEVANCE:

Prone positioning improves oxygenation across the acute respiratory distress syndrome severity spectrum, irrespective of supine respiratory system compliance, positive end-expiratory pressure, or body mass index. There was a greater relative benefit among patients with more severe disease. Prone positioning confers an additive benefit in oxygenation among patients treated with inhaled nitric oxide.

Early Use of Adjunctive Therapies for Pediatric Acute Respiratory Distress Syndrome: A PARDIE Study

Rationale: Few data exist to guide early adjunctive therapy use in pediatric acute respiratory distress syndrome (PARDS).Objectives: To describe contemporary use of adjunctive therapies for early PARDS as a framework for future investigations.Methods: This was a preplanned substudy of a prospective, international, cross-sectional observational study of children with PARDS from 100 centers over 10 study weeks.Measurements and Main Results: We investigated six adjunctive therapies for PARDS: continuous neuromuscular blockade, corticosteroids, inhaled nitric oxide (iNO), prone positioning, high-frequency oscillatory ventilation (HFOV), and extracorporeal membrane oxygenation. Almost half (45%) of children with PARDS received at least one therapy. Variability was noted in the median starting oxygenation index of each therapy; corticosteroids started at the lowest oxygenation index (13.0; interquartile range, 7.6-22.0) and HFOV at the highest (25.7; interquartile range, 16.7-37.3). Continuous neuromuscular blockade was the most common, used in 31%, followed by iNO (13%), corticosteroids (10%), prone positioning (10%), HFOV (9%), and extracorporeal membrane oxygenation (3%). Steroids, iNO, and HFOV were associated with comorbidities. Prone positioning and HFOV were more common in middle-income countries and less frequently used in North America. The use of multiple ancillary therapies increased over the first 3 days of PARDS, but there was not an easily identifiable pattern of combination or order of use.Conclusions: The contemporary description of prevalence, combinations of therapies, and oxygenation threshold for which the therapies are applied is important for design of future studies. Region of the world, income, and comorbidities influence adjunctive therapy use and are important variables to include in PARDS investigations.

The Current State of Pediatric Acute Respiratory Distress Syndrome

Pediatric acute respiratory distress syndrome (PARDS) is a significant cause of morbidity and mortality in children. Children with PARDS often require intensive care admission and mechanical ventilation. Unfortunately, beyond lung protective ventilation, there are limited data to support our management strategies in PARDS. The Pediatric Acute Lung Injury Consensus Conference (PALICC) offered a new definition of PARDS in 2015 that has improved our understanding of the true epidemiology and heterogeneity of the disease as well as risk stratification. Further studies will be crucial to determine optimal management for varying disease severity. This review will present the physiologic basis of PARDS, describe the unique pediatric definition and risk stratification, and summarize the current evidence for current standards of care as well as adjunctive therapies.

Guidelines on the management of acute respiratory distress syndrome

The Faculty of Intensive Care Medicine and Intensive Care Society Guideline Development Group have used GRADE methodology to make the following recommendations for the management of adult patients with acute respiratory distress syndrome (ARDS). The British Thoracic Society supports the recommendations in this guideline. Where mechanical ventilation is required, the use of low tidal volumes (<6 ml/kg ideal body weight) and airway pressures (plateau pressure <30 cmH₂O) was recommended. For patients with moderate/severe ARDS (PF ratio<20 kPa), prone positioning was recommended for at least 12 hours per day. By contrast, high frequency oscillation was not recommended and it was suggested that inhaled nitric oxide is not used. The use of a conservative fluid management strategy was suggested for all patients, whereas mechanical ventilation with high positive end-expiratory pressure and the use of the neuromuscular blocking agent cisatracurium for 48 hours was suggested for patients with ARDS with ratio of arterial oxygen partial pressure to fractional inspired oxygen (PF) ratios less than or equal to 27 and 20 kPa, respectively. Extracorporeal membrane oxygenation was suggested as an adjunct to protective mechanical ventilation for patients with very severe ARDS. In the absence of adequate evidence, research recommendations were made for the use of corticosteroids and extracorporeal carbon dioxide removal.

Efficacy of prone position in acute respiratory distress syndrome: overview of systematic reviews

OBJECTIVE

To identify and integrate the available scientific evidence related to the use of the prone position in patients with acute respiratory distress syndrome for the reduction of the outcome variable of mortality compared to the dorsal decubitus position.

METHOD

Overview of systematic reviews or meta-analyzes of randomized clinical trials. It included studies that evaluated the use of prone positioning in patients with acute respiratory distress syndrome published between 2014 and 2016. The AMSTAR tool was used to determine the methodological quality of studies. The GRADE system was used to establish the overall quality of evidence for the mortality outcome.

RESULTS

From the search strategy, were retrieved seven relevant manuscripts of high methodological quality.

CONCLUSION

Scientific evidence supports that combined use of protective ventilatory strategy and prone positioning for periods between 16 and 20 hours in patients with acute respiratory distress syndrome and PaO2/FiO2 ratio lower than 150 mm/Hg results in significant reduction of mortality rate.

Pediatric Acute Hypoxemic Respiratory Failure: Management of Oxygenation

Acute hypoxemic respiratory failure (AHRF) is one of the hallmarks of acute lung injury (ALI) and acute respiratory distress syndrome (ARDS), which are caused by an inflammatory process initiated by any of a number of potential systemic and/or pulmonary insults that result in heterogeneous disruption of the capillary-pithelial interface. In these critically sick patients, optimizing the management of oxygenation is crucial. Physicians managing pediatric patients with ALI or ARDS are faced with a complex array of options influencing oxygenation. Certain treatment strategies can influence clinical outcomes, such as a lung protective ventilation strategy that specifies a low tidal volume (6 mL/kg) and a plateau pressure limit (30 cm H2O). Other strategies such as different levels of positive end expiratory pressure, altered inspiration to expiration time ratios, recruitment maneuvers, prone positioning, and extraneous gases or drugs may also affect clinical outcomes. This article reviews state-of-the-art strategies on the management of oxygenation in acute hypoxemic respiratory failure in children.

Prone position for acute respiratory failure in adults

BACKGROUND

Acute hypoxaemia de novo or on a background of chronic hypoxaemia is a common reason for admission to intensive care and for provision of mechanical ventilation. Various refinements of mechanical ventilation or adjuncts are employed to improve patient outcomes. Mortality from acute respiratory distress syndrome, one of the main contributors to the need for mechanical ventilation for hypoxaemia, remains approximately 40%. Ventilation in the prone position may improve lung mechanics and gas exchange and could improve outcomes.

OBJECTIVES

The objectives of this review are (1) to ascertain whether prone ventilation offers a mortality advantage when compared with traditional supine or semi recumbent ventilation in patients with severe acute respiratory failure requiring conventional invasive artificial ventilation, and (2) to supplement previous systematic reviews on prone ventilation for hypoxaemic respiratory failure in an adult population.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL; 2014, Issue 1), Ovid MEDLINE (1950 to 31 January 2014), EMBASE (1980 to 31 January 2014), the Cumulative Index to Nursing and Allied Health Literature (CINAHL) (1982 to 31 January 2014) and Latin American Caribbean Health Sciences Literature (LILACS) (1992 to 31 January 2014) in Ovid MEDLINE for eligible randomized controlled trials. We also searched for studies by handsearching reference lists of relevant articles, by contacting colleagues and by handsearching published proceedings of relevant journals. We applied no language constraints, and we reran the searches in CENTRAL, MEDLINE, EMBASE, CINAHL and LILACS in June 2015. We added five new studies of potential interest to the list of "Studies awaiting classification" and will incorporate them into formal review findings during the review update.

SELECTION CRITERIA

We included randomized controlled trials (RCTs) that examined the effects of prone position versus supine/semi recumbent position during conventional mechanical ventilation in adult participants with acute hypoxaemia.

DATA COLLECTION AND ANALYSIS

Two review authors independently reviewed all trials identified by the search and assessed them for suitability, methods and quality. Two review authors extracted data, and three review authors reviewed the data extracted. We analysed data using Review Manager software and pooled included studies to determine the risk ratio (RR) for mortality and the risk ratio or mean difference (MD) for secondary outcomes; we also performed subgroup analyses and sensitivity analyses.

MAIN RESULTS

We identified nine relevant RCTs, which enrolled a total of 2165 participants (10 publications). All recruited participants suffered from disorders of lung function causing moderate to severe hypoxaemia and requiring mechanical ventilation, so they were fairly comparable, given the heterogeneity of specific disease diagnoses in intensive care. Risk of bias, although acceptable in the view of the review authors, was inevitable: Blinding of participants and carers to treatment allocation was not possible (face-up vs face-down).Primary analyses of short- and longer-term mortality pooled from six trials demonstrated an RR of 0.84 to 0.86 in favour of the prone position (PP), but findings were not statistically significant: In the short term, mortality for those ventilated prone was 33.4% (363/1086) and supine 38.3% (395/1031). This resulted in an RR of 0.84 (95% confidence interval (CI) 0.69 to 1.02) marginally in favour of PP. For longer-term mortality, results showed 41.7% (462/1107) for prone and 47.1% (490/1041) for supine positions, with an RR of 0.86 (95% CI 0.72 to 1.03). The quality of the evidence for both outcomes was rated as low as a result of important potential bias and serious inconsistency.Subgroup analyses for mortality identified three groups consistently favouring PP: those recruited within 48 hours of meeting entry criteria (five trials; 1024 participants showed an RR of 0.75 (95% CI 0.59 to 94)); those treated in the PP for 16 or more hours per day (five trials; 1005 participants showed an RR of 0.77 (95% CI 0.61 to 0.99)); and participants with more severe hypoxaemia at trial entry (six trials; 1108 participants showed an RR of 0.77 (95% CI 0.65 to 0.92)). The quality of the evidence for these outcomes was rated as moderate as a result of potentially important bias.Prone positioning appeared to influence adverse effects: Pressure sores (three trials; 366 participants) with an RR of 1.37 (95% CI 1.05 to 1.79) and tracheal tube obstruction with an RR of 1.78 (95% CI 1.22 to 2.60) were increased with prone ventilation. Reporting of arrhythmias was reduced with PP, with an RR of 0.64 (95% CI 0.47 to 0.87).

AUTHORS' CONCLUSIONS

We found no convincing evidence of benefit nor harm from universal application of PP in adults with hypoxaemia mechanically ventilated in intensive care units (ICUs). Three subgroups (early implementation of PP, prolonged adoption of PP and severe hypoxaemia at study entry) suggested that prone positioning may confer a statistically significant mortality advantage. Additional adequately powered studies would be required to confirm or refute these possibilities of subgroup benefit but are unlikely, given results of the most recent study and recommendations derived from several published subgroup analyses. Meta-analysis of individual patient data could be useful for further data exploration in this regard. Complications such as tracheal obstruction are increased with use of prone ventilation. Long-term mortality data (12 months and beyond), as well as functional, neuro-psychological and quality of life data, are required if future studies are to better inform the role of PP in the management of hypoxaemic respiratory failure in the ICU.

Pulmonary specific ancillary treatment for pediatric acute respiratory distress syndrome: proceedings from the Pediatric Acute Lung Injury Consensus Conference

OBJECTIVE

To provide an overview of the current literature on pulmonary-specific therapeutic approaches to pediatric acute respiratory distress syndrome to determine recommendations for clinical practice and/or future research.

DATA SOURCES

PubMed, EMBASE, CINAHL, SCOPUS, and the Cochrane Library were searched from inception until January 2013 using the following keywords in various combinations: ARDS, treatment, nitric oxide, heliox, steroids, surfactant, etanercept, prostaglandin therapy, inhaled beta adrenergic receptor agonists, N-acetylcysteine, ipratroprium bromide, dornase, plasminogen activators, fibrinolytics or other anticoagulants, and children. No language restrictions were applied. References from identified articles were searched for additional publications.

STUDY SELECTION

All clinical studies pertaining to pulmonary-specific therapeutic approaches to pediatric acute respiratory distress syndrome were reviewed. If clinical pediatric data were sparse or unavailable, the findings from studies of adult acute respiratory distress syndrome and animal models that might be relevant to pediatric acute respiratory distress syndrome were examined.

DATA EXTRACTION

All relevant studies were reviewed and pertinent data abstracted.

DATA SYNTHESIS

Over the course of three international meetings, the pertinent findings of the literature review were discussed by a panel of 24 experts in the field representing 21 academic institutions and 8 countries. Recommendations developed and the supporting literature were distributed to all panel members without a conflict of interest and were scored by using the Research ANd Development/University of California, Los Angeles Appropriateness method. The modified Delphi approach was used as the methodology to achieve consensus among the panel.

CONCLUSIONS

Overall, the routine use of surfactant, inhaled nitric oxide, glucocorticoids, prone positioning, endotracheal suctioning, and chest physiotherapy cannot be recommended. Inhaled nitric oxide should only be used for patients with documented pulmonary hypertension and/or right ventricular failure. Prone positioning may be considered in patients with severe pediatric acute respiratory distress syndrome. Future studies are definitely warranted to establish the role, if any, of these ancillary treatment modalities in pediatric acute respiratory distress syndrome.

Chin necrosis as a consequence of prone positioning in the intensive care unit

Pressure necrosis of the skin is a rarely reported avoidable complication of prone positioning that can be minimised by active collaboration between care teams. We report a case of pressure necrosis of the chin after prone ventilation in the intensive care setting. Such injuries pose a risk of infection, possible need for surgical intervention, and increased costs to the health care system. Pressure necrosis injuries should be diligently guarded against by the careful selection of support devices, frequent turning, and rigorous skin care to minimise extended external compression, particularly on the face and bony prominences.

Positioning for acute respiratory distress in hospitalised infants and children

BACKGROUND

Because of the association of prone positioning with sudden infant death syndrome (SIDS) it is recommended that young infants be placed on their backs (supine). However, the prone position may be a non-invasive way of increasing oxygenation in participants with acute respiratory distress. Because of substantial differences in respiratory mechanics between adults and children and the risk of SIDS in young infants, a specific review of positioning for infants and young children with acute respiratory distress is warranted.

OBJECTIVES

To compare the effects of different body positions in hospitalised infants and children with acute respiratory distress.

SEARCH METHODS

We searched Cochrane Central Register of Controlled Trials (CENTRAL 2012, Issue 3), which contains the Acute Respiratory Infections Group's Specialised Register, MEDLINE (1966 to April week 1, 2012), EMBASE (2004 to April 2012) and CINAHL (2004 to April 2012).

SELECTION CRITERIA

Randomised controlled trials (RCTs) or pseudo-RCTs comparing two or more positions in the management of infants and children hospitalised with acute respiratory distress.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data from each study. We resolved differences by consensus or referral to a third review author. We analysed bivariate outcomes using an odds ratio and 95% confidence interval (CI). We analysed continuous outcomes using a mean difference and 95% CI. We used a fixed-effect model unless heterogeneity was significant, in which case we used a random-effects model.

MAIN RESULTS

We extracted data from 53 studies. We included 24 studies with a total of 581 participants. Three studies used a parallel-group, randomised design which compared prone and supine positions only. The remaining 21 studies used a randomised cross-over design. These studies compared prone, supine, lateral, elevated and flat positions.Prone positioning was significantly more beneficial than supine positioning in terms of oxygen saturation (mean difference (MD) 1.97%, 95% CI 1.18 to 2.77), arterial oxygen (MD 6.24 mm Hg, 95% confidence interval (CI) 2.20 to 10.28), episodes of hypoxaemia (MD -3.46, 95% CI -4.60 to -2.33) and thoracoabdominal synchrony (MD -30.76, 95% CI -41.39 to -20.14). No adverse effects were identified. There were no statistically significant differences between any other positions.As the majority of studies did not describe how possible biases were addressed, the potential for bias in these findings is unclear.

AUTHORS' CONCLUSIONS

The prone position was significantly superior to the supine position in terms of oxygenation. However, as most participants were ventilated preterm infants, the benefits of prone positioning may be most relevant to these infants. In addition, although placing infants and children in the prone position may improve respiratory function, the association of SIDS with prone positioning means that infants should only be placed in this position while under continuous cardiorespiratory monitoring.

Clinical research: together, stronger, bolder

Clinical inquiry is the ongoing process of questioning and evaluating practice, providing informed practice based on best-available data, and innovating practice though research. It is about noticing subtle differences at the bedside and asking "what if" questions. Critically ill patients and their families require care that is based on our best-available evidence. In the quantitative research paradigm, the highest level of evidence is derived from randomized controlled clinical trials. Currently, few adequately powered clinical trials support our practice, but this is changing. In critical care, clinical research should be conducted in the same manner as we practice, collaboratively within multidisciplinary teams. Our core value of the primacy of patient and family, our spirit of inquiry, and our passion for innovation centers our practice. During this year's Distinguished Research Lecture, Martha Curley describes how together, we can build stronger, bolder clinical research.

Posture-induced intraocular pressure changes: considerations regarding body position in glaucoma patients

Although glaucoma is a multifactorial disease, elevated intraocular pressure (IOP) remains the most important known risk factor. Different systemic and local factors are thought to influence an individual's IOP. There can be a clinically significant rise in IOP when going from upright to horizontal or inverted body positions. Although there is a significant interindividual variability, the magnitude of the IOP change is greater in glaucomatous eyes. As patients usually spend a significant portion of their lives in the horizontal position, mainly during sleep, this is highly relevant. In this review we discuss the relationship between postural changes and IOP fluctuation, including changes in both body and head position. The possible mechanisms involved and the main implications for glaucomatous eyes are discussed. Finally, considerations with regard to sleep position in glaucoma patients are made based on evidence in the literature.

Therapeutic positioning of the multiply-injured trauma patient in ICU

Critically-ill patients who have sustained multiple traumatic injuries have complex, and often conflicting, physiological needs. These have profound implications on the way in which nursing staff approach the physical positioning of these patients to minimize the risks of further physiological injury and damage, maintain homeostasis and promote optimum recovery. This article reviews and discusses the evidence base underpinning therapeutic positioning of the multiply-injured trauma patient within the intensive-care unit (ICU), focusing on patients with a known or suspected unstable spinal injury, pelvic injury, traumatic brain injury, chest injury, or multiple limb fractures. Included are guidelines on the therapeutic positioning of the multiply-injured trauma patient within the ICU, based on the current available evidence and also drawn from practical experience within the author's own place of work. There is also a brief discussion of how such guidelines may be introduced into clinical practice.

A systematic approach to care: adult respiratory distress syndrome

Trauma patients present with and have the potential to develop an array of systemic and metabolic disturbances. Adult respiratory distress syndrome has been identified as a life-threatening development, especially in trauma patients. A systematic approach to care utilizing the acronyms FASTHUG and BANDAIDS, along with incorporating lung protective strategies, provides avenues to decrease mortality related to adult respiratory distress syndrome. A case study presentation, pathophysiology related to symptoms, interventions, and clinical outcomes are presented.

Prone equals prone? Impact of positioning techniques on respiratory function in anesthetized and paralyzed healthy children

OBJECTIVES

Although the prone position is effectively used to improve oxygenation, its impact on functional residual capacity is controversial. Different techniques of body positioning might be an important confounding factor. The aim of this study was to determine the impact of two different prone positioning techniques on functional residual capacity and ventilation distribution in anesthetized, preschool-aged children.

DESIGN

Functional residual capacity and lung clearance index, a measure of ventilation homogeneity, were calculated using a sulfur-hexafluoride multibreath washout technique. After intubation, measurements were taken in the supine position and, in random order, in the flat prone position and the augmented prone position (gel pads supporting the pelvis and the upper thorax).

SETTING

Pediatric anesthesia unit of university hospital.

PATIENTS AND PARTICIPANTS

Thirty preschool children without cardiopulmonary disease undergoing elective surgery.

MEASUREMENTS AND RESULTS

Mean (range) age was 48.5 (24-80) months, weight 17.2 (10.5-26.9) kg, functional residual capacity (mean +/- SD) 22.9+/- 6.2 ml.kg (-1) in the supine position and 23.3 +/- 5.6 ml.kg (-1) in the flat prone position, while lung clearance indices were 8.1 +/- 2.3 vs. 7.9 +/- 2.3, respectively. In contrast, functional residual capacity increased to 27.6 +/- 6.5 ml.kg (-1) (p< 0.001) in the augmented prone position while at the same time the lung clearance index decreased to 6.7 +/- 0.9 (p< 0.001).

CONCLUSIONS

Functional residual capacity and ventilation distribution were similar in the supine and flat prone positions, while these parameters improved significantly in the augmented prone position, suggesting that the technique of prone positioning has major implications for pulmonary function.

Pressure Ulcers in Neonates and Children

Acutely ill and immobilized neonates and children are at risk for pressure ulcers, but a paucity of evidence-based research exists on which to base guidelines for clinical practice. Most prevention and treatment protocols for pressure ulcers in the pediatric population are extrapolated from adult practice. Clinical practice guidelines for prevention and treatment of pressure ulcers that specifically address the needs of the pediatric population are needed. The purpose of this article is to highlight the research that is currently available and to identify gaps that need to be addressed so that science-based, age-appropriate prevention and treatment pressure ulcer guidelines can be developed.

Positioning practices for ventilated intensive care patients: current practice, indications and contraindications

To investigate the process of providing patient positioning in intensive care units (ICUs), a self-reported survey was distributed to a senior physiotherapist and a nurse in each of the 38 Level 3 Australian ICUs. The survey explored the rationales, aims, type, frequency and duration of directed patient positioning used, and perceived risks that may impede the implementation of an effective positioning regime. The response rate was 93%. Fifty nine respondents (83%) agreed that there is an accepted standard of care for the duration of a position change with ventilated patients. Of these respondents, 51 (86%) agreed that the standard is to turn patients every 2 hours, but this was only achievable "more than 50% of the time" in 47% (n=34) of ICUs. Educational and environmental issues were found to impact on positioning practices. Semi-recumbent and full side-lie positions were recommended in the management of a range of patient conditions. However, full side-lie was less commonly used than supine positioning. The prone and head down tilt positions were the least frequently utilised. Levels of agreement for precautions and contraindications to positioning patients into full side-lie and sitting were high. We conclude that, in Australia, experienced ICU physiotherapy and nursing staff are aware of evidence-based positioning practices and agree on indications and potential risk factors associated with positioning. However, educational and environmental resources are needed to improve the frequency and type of positioning used. Results from this survey can now be incorporated into educational tools to facilitate the safe use of positioning.

Prone positioning can be safely performed in critically ill infants and children

OBJECTIVE

To describe the effects of prone positioning on airway management, mechanical ventilation, enteral nutrition, pain and sedation management, and staff utilization in infants and children with acute lung injury.

DESIGN

Secondary analysis of data collected in a multiple-center, randomized, controlled clinical trial of supine vs. prone positioning.

SETTING

Seven pediatric intensive care units located in the United States.

PATIENTS

One hundred and two pediatric patients (51 prone and 51 supine) with acute lung injury.

INTERVENTIONS

Patients randomized to the supine group remained supine. Patients randomized to the prone group were positioned prone per protocol during the acute phase of their illness for a maximum of 7 days. Both groups were managed using ventilator and sedation protocols and nutrition and skin care guidelines.

MEASUREMENTS AND MAIN RESULTS

Airway management and mechanical ventilatory variables before and after repositioning, enteral nutrition management, pain and sedation management, staff utilization, and adverse event data were collected for up to 28 days after enrollment. There were a total of 202 supine-prone-supine cycles. There were no differences in the incidence of endotracheal tube leak between the two groups (p = .30). Per protocol, 95% of patients remained connected to the ventilator during repositioning. The inadvertent extubation rate was 0.85 for the prone group and 1.03 for the supine group per 100 ventilator days (p = 1.00). There were no significant differences in the initiation of trophic (p = .24), advancing (p = .82), or full enteral feeds (p = .80) between the prone and supine groups; in the average pain (p = .81) and sedation (p = .18) scores during the acute phase; and in the amount of comfort medications received between the two groups (p = .91). There were no critical events during a turn procedure. While prone, two patients experienced an obstructed endotracheal tube. One patient, supported on high-frequency oscillatory ventilation, experienced persistent hypercapnea when prone and was withdrawn from the study. The occurrence of pressure ulcers was similar between the two groups (p = .71). Compared with the supine group, more staff (p </= .001) and more time were necessary to reposition patients in the prone group.

CONCLUSIONS

Our data show that prone positioning can be safely performed in critically ill pediatric patients and that these patients can be safely managed while in the prone position for prolonged periods of time.

Lateralización como alternativa al decúbito prono estático en pacientes con SDRA

According to Phillips, Continuous Lateral Rotation (CLR) or Kinetic Therapy (KT) together with the technological advances obtain some important benefits in mechanically ventilated patients.

OBJECTIVE

Compare Static Prone Decubitus (PD) with DP in CRL.

PATIENTS AND METHODS

We analyzed 2 groups with a total of 41 patients in the period of January 1998 to April 2003. The DP group (25 patients) remained static and the lateral group (16 patients) in CLR every 2 h. The groups had 56 +/- 16 vs 64 +/- 17 years, 77 +/- 20 vs 71 +/- 23 kg and 24% vs 31% of survival, respectively.

RESULTS

We maintained the PD 37 +/- 30 vs 27 +/- 36 h for group 1 and 2. The response as Responders is 68% and 69%. pO2/FiO2 of supine pre-DP to supine post-DP is 79 +/- 21 to 146 +/- 68 versus 80 +/- 20 to 138 +/- 57 and pulmonary compliance 22 +/- 10 to 21 +/- 10 vs 31 +/- 10 to 32 +/- 9. Mean blood pressure of S to S was 87 +/- 16 to 85 +/- 15 vs 82 +/- 10 to 80 +/- 9, and mean Heart rate 108 +/- 21 to 95 +/- 24 vs 85 +/- 32 to 75 +/- 28. Complications by groups were: facial edema of 84% vs 63%, gastric retention 36% to 38%, vomiting/regurgitation 12% to 0%, epistaxis 8% to 31%. Pressure Sore (PS) Incidence decreased from 36% to 12%, together with seriousness.

CONCLUSION

We consider that lateralization if PD is a technique comparable to static PD on the respiratory and hemodynamics level. CLR in PD may prevent some complications.

The value of electrical impedance tomography in assessing the effect of body position and positive airway pressures on regional lung ventilation in spontaneously breathing subjects

OBJECTIVE

Functional electrical impedance tomography (EIT) measures relative impedance changes in lung tissue during tidal breathing and creates images of local ventilation distribution. A novel approach to analyse the effect of body position and positive pressure ventilation on intrapulmonary tidal volume distribution was evaluated in healthy adult subjects.

DESIGN AND SETTING

Prospective experimental study in healthy adult subjects in the intensive care unit at university hospital.

SUBJECTS

Ten healthy male adults.

INTERVENTIONS

Change in body position from supine to prone, left and right lateral during spontaneous breathing and positive pressure support ventilation.

MEASUREMENTS AND RESULTS

EIT measurements and multiple-breath sulphur hexafluoride (SF6) washout were performed. Profiles of average relative impedance change in regional lung areas were calculated. Relative impedance time course analysis and Lissajous figure loop analysis were used to calculate phase angles between dependent or independent lung and total lung (phi). EIT data were compared to SF6 data washout measuring the lung clearance index (LCI). Proposed EIT profiles allowed inter-individual comparison of EIT data and identified areas with reduced regional tidal volume using pressure support ventilation. Phase angle phi of dependent lung in supine position was 11.7+/-1.4 degrees, in prone 5.3+/-0.5 degrees, in right lateral 11.0+/-1.3 degrees and in left lateral position 10.8+/-1.0 degree. LCI increased in supine position from 5.63+/-0.43 to 7.13+/-0.64 in prone position. Measured phi showed inverse relationship to LCI in the four different body positions.

CONCLUSIONS

EIT profiles and phi of functional EIT are new methods to describe regional ventilation distribution with EIT allowing inter-individual comparison.

Positioning for acute respiratory distress in hospitalised infants and children

BACKGROUND

Because of the association between prone positioning and sudden infant death syndrome SIDS) it is recommended that young infants be placed on their backs (supine). However, the supine position might not be the most appropriate position for infants and children hospitalised with acute respiratory distress. Positioning patients has been proposed as a non-invasive way of increasing oxygenation in adult patients with acute respiratory distress. But, because of substantial differences in respiratory mechanics between adults and children and the risk of SIDS in young infants, a specific review of positioning for infants and young children with acute respiratory distress is warranted.

OBJECTIVES

To compare the effects of different body positions in hospitalised infants and children with acute respiratory distress.

SEARCH STRATEGY

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library Issue 3, 2004); MEDLINE (January 1966 to October Week 3, 2004); EMBASE (1980 to week 24, 2004); and CINAHL (1982 to October Week 3, 2004).

SELECTION CRITERIA

All randomised or systematically-allocated controlled clinical trials comparing two or more positions in the management of infants and children hospitalised with acute respiratory distress.

DATA COLLECTION AND ANALYSIS

Data were extracted from each study independently by two authors. Differences were resolved by consensus or referral to a third author. Continuous outcomes were analysed using a weighted mean difference and 95% confidence interval. No bivariate outcomes were available. All but one included study reported crossover data therefore this data was used for meta-analysis. Fixed-effect models were used unless heterogeneity was significant (p value equal to or less than 0.1), in which case a random-effects model was used.

MAIN RESULTS

Forty-nine papers were selected for this review of which 21 studies (22 publications) were included. These studies compared prone, supine, lateral, elevated, and flat positions. Prone positioning was significantly more beneficial than supine positioning in terms of oxygen saturation, partial pressure of arterial oxygen, oxygenation index, thoraco-abdominal synchrony, and episodes of desaturation. There were no statistically significant differences between any other positions.

AUTHORS' CONCLUSIONS

The prone position was significantly superior to the supine position in terms of oxygenation. However, as most patients included in the meta-analysis were ventilated, preterm infants the benefits of prone positioning may be most relevant to these infants. In addition, although placing infants and children in the prone position may improve respiratory function, the association of sudden infant death with prone positioning means that infants should only be placed in this position if continuous cardiorespiratory monitoring is used.

Prone positioning in the patient who has acute respiratory distress syndrome: the art and science

Acute respiratory distress syndrome (ARDS) remains a significant contributor to the morbidity and mortality of patients in the ICU. A variety of treatments are used to support the lung of the patient who has ARDS and improve gas exchange during the acute injury phase. It seems, however, that the simple, safe, and noninvasive act of prone positioning of the critically ill patient who has ARDS may improve gas exchange while preventing potential complications of high positive end-expiratory pressure, volutrauma, and oxygen toxicity. This article provides the critical care nurse with the physiologic rationale for use of the prone position, indications and contraindications for use, safe strategies for prone positioning, and care techniques and monitoring methods of the patient who is in the prone position.

Response to the prone position in spontaneously breathing patients with hypoxemic respiratory failure

OBJECTIVES

The prone position is used for intubated patients with adult respiratory distress syndrome (ARDS) and acute lung injury (ALI). The physiological changes associated with the prone position in nonintubated patients may be even more favorable than in intubated patients. We examined the effect of the prone position on arterial blood gases and patient compliance in four awake, nonintubated patients with hypoxemic respiratory failure.

DESIGN

We present four consecutive cases of hypoxemic respiratory failure, in which mechanical ventilation was indicated. An attempt was made to avoid assisted ventilation by placing patients in the prone position, while breathing spontaneously. The effect on the clinical condition and the changes in blood gases were registered.

RESULTS

We found good patient tolerance. A rapid increase in PaO2 was found, and intubation was avoided in all patients. No significant complications were registered.

CONCLUSION

The prone position may prove beneficial in some cases of hypoxemic respiratory failure, even in awake patients, by avoiding mechanical ventilation and ventilator-associated complications.

Subjective Perceptions and Physiological Variables During Weaning From Mechanical Ventilation

• Background As costs related to mechanical ventilation increase, clear indicators of patients’ readiness to be weaned are needed. Research has not yet yielded a consensus on physiological variables that are consistent correlates of weaning outcomes. Subjective perceptions rarely have been examined for their contribution to successful weaning.

• Objective To explore the subjective perceptions of dyspnea, fatigue, and self-efficacy and selected physiological variables in patients being weaned from mechanical ventilation.

• Methods Data were collected prospectively on 68 patients being weaned from mechanical ventilation. Subjective perceptions were measured by using 3 visual analog scales; physiological variables were measured by using the Burns Weaning Assessment Program and a patient profile. Weaning outcomes were recorded 24 hours after data collection.

• Results Participants were primarily white women and required mechanical ventilation for a mean of less than 4 days. Participants reported mild dyspnea, moderate fatigue, and high weaning self-efficacy. High Pao2, low Paco2, stable hemodynamic status, adequate cough and swallow reflexes, no metabolic changes, and no abdominal problems were associated with complete weaning (P = .05). Subjective perceptions were associated with physiological variables but not with weaning outcomes.

• Conclusions Multidimensional assessment of both primary and secondary indicators of readiness to be weaned is necessary for timely, efficient weaning from mechanical ventilation. Primary assessments include physiological variables related to gas exchange, hemodynamic status, diaphragmatic expansion, and airway clearance. Secondary assessments include perceptions related to key physiological variables. Additional research is needed to determine the predictive value of physiological variables and perceptions of dyspnea, fatigue, and self-efficacy.

Bilateral anterior superior iliac spine pressure ulcers: a case report

The most frequent sites for pressure ulcers are the occiput, sacrum, ischial tuberosities, trochanters, lateral malleoli, and posterior heels. A 27-year-old woman with Wegener's granulomatosis was admitted to our rehabilitation unit after spending 65 days in an intensive care unit and 40 days in an internal medicine ward. She required mechanical ventilation because of respiratory failure. Adequate oxygenation was only achieved in the prone position. As a result, she developed bilateral anterior superior iliac spine pressure ulcers. Pressure ulcers in this location have not been reported in the literature. Complicating factors included variable levels of oxygenation, malnutrition, anemia, and steroid therapy. Complete healing, documented with serial photographs, occurred over 9 months. Although prone positioning can improve pulmonary gas exchange, it exposes the patient to unique complications. When it is required, specific care should be directed to the unusual weight-bearing surfaces to avoid pressure ulcers.

Similar ventilation distribution in normal subjects prone and supine during tidal breathing

Multiple-breath washout (MBW) tests, with end-expiratory lung volume at functional residual capacity (FRC) and 90% O(2), 5% He, and 5% SF(6) as an inspired gas mixture, were performed in healthy volunteers in supine and prone postures. The semilog plot of MBW N(2) concentrations was evaluated in terms of its curvilinearity. The MBW N(2) normalized slope analysis yielded indexes of acinar and conductive ventilation heterogeneity (Verbanck S, Schuermans D, Van Muylem A, Paiva M, Noppen M, and Vincken W. J App Physiol 83: 1907-1916, 1997). Also, the difference between SF(6) and He normalized phase III slopes was computed in the first MBW expiration. Only MBW tests with similar FRC in the prone and supine postures (P > 0.1; n = 8) were considered. Prone and supine postures did not reveal any significant differences in curvilinearity, N(2) normalized slope-derived indexes of conductive or acinar ventilation heterogeneity, nor SF(6)-He normalized phase III slope difference in the first MBW expiration (P > 0.1 for all). The absence of significant changes in any of the MBW indexes suggests that ventilation heterogeneity is similar in the supine and prone postures of normal subjects breathing near FRC.

Elements of a systematic review

This paper examines the subject of systematic reviews from a nursing viewpoint. The history of the evidence-based healthcare movement and the major differences between systematic reviews and traditional literature reviews are discussed. The steps of the process used by those conducting reviews are examined in detail. These include structuring a research question, searching and appraising the literature, data extraction, analysis and synthesis, and reporting the results. It is this process that ensures reviews can be considered as a legitimate form of nursing research.

Acute respiratory distress syndrome: physiology and new management strategies

The acute respiratory distress syndrome (ARDS) has been recognized for more than three decades as a cause of respiratory failure in patients with a variety of illnesses. Clinically, it is characterized by pulmonary edema, refractory hypoxemia, diffuse pulmonary infiltrates, and altered lung compliance. Pathologically, it is distinguished by infiltration of the lungs with inflammatory cells, interstitial and alveolar edema, hyaline membrane formation, and ultimately fibrosis. Although we have learned much about the pathophysiology of this inflammatory syndrome since its earliest descriptions, ARDS continues to claim the lives of 40%-70% of its victims. Many treatment strategies have been used to prevent or treat ARDS, but thus far the most encouraging strategy to prevent lung injury and improve survival is mechanical ventilation with low tidal volumes and high levels of positive end-expiratory pressure.

Clinical guidelines for the use of the prone position in acute respiratory distress syndrome

The mortality associated with acute respiratory distress syndrome (ARDS) remains high. It has been suggested that use of the prone position may improve survival. However, approaches to the use of the position are often haphazard. The development of clinical guidelines indicating the need for the prone position in ARDS and the process by which the manoeuvre may be performed were thought to be important for two reasons. Primarily, we sought to improve oxygenation through the use of the prone position whilst promoting patient safety. Secondly, we wished to standardize our approach to the use of the prone position and make recommendations for practice so that its use was no longer seen as a last resort in the management of ARDS. The process associated with the development of clinical guidelines is first described. This is followed by presentation of the clinical guidelines. Included in these are the criteria and discussion which indicate consideration of the prone position, potential exclusion criteria, pre-turn considerations, the turning technique, monitoring the effectiveness of the prone position, passive movements and limb positioning and, finally, documentation of the problems associated with use of the prone position. The paper concludes with discussion concerning the potential for future research in this area.

The effects of early and repeated prone positioning in pediatric patients with acute lung injury

STUDY OBJECTIVE

To describe the physiologic changes and to evaluate the safety of placing pediatric patients with acute lung injury (ALI) prone for 20 h/d during the acute phase of their illness.

DESIGN

Single-center prospective case series.

SETTING

Tertiary-level pediatric ICU.

PATIENTS

Consecutive patients with bilateral pulmonary parenchymal disease requiring intubation and mechanical ventilation with a PaO(2)/fraction of inspired oxygen (FIO(2)) ratio </= 300 mm Hg.

INTERVENTIONS

Patients were enrolled as soon as possible after meeting criteria and were placed in a prone position for 20 h/d daily until clinical improvement or death occurred.

MEASUREMENTS AND RESULTS

Twenty-five pediatric patients who had ALI/ARDS, ranging in age from 2 months to 17 years, were placed in a prone position within 19 h of meeting the study criteria for a median time of 4 days, which accounted for 47% of their time receiving mechanical ventilation. Eighty-four percent of patients (n = 21) were categorized as overall responders to prone positioning because they experienced more days of increases of >/= 20 mm Hg in PaO(2)/FIO(2) ratio or a decrease of >/= 10% in oxygenation index when shifted from a supine to a prone position during the study period. During the 107 patient-days and 214 positioning cycles, no critical incidents occurred. Furthermore, no patient experienced a persistent decrease in oxygen saturation as measured by pulse oximetry (SpO(2)) of > 10% from values obtained when in the supine position, failed to keep their SpO(2) at > 85%, or experienced an increased respiratory rate of > 40 breaths/min when prone. Using the COMFORT score, patients were objectively rated to be equally comfortable in both the supine and prone positions. Patients also were able to resume spontaneous ventilation and to progress toward endotracheal extubation while in the prone position. Iatrogenic injury associated with prolonged prone positioning included stage II pressure ulcers in six patients (24%).

CONCLUSIONS

The pediatric patients in this series demonstrated improvements in oxygenation without serious iatrogenic injury after prone positioning. This study provides a foundation for a prospective randomized study investigating the effect of early and repeated prone positioning on clinical outcomes in pediatric patients with ALI.