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ORIGINAL ARTICLE
Year : 2016  |  Volume : 2  |  Issue : 2  |  Page : 81-88

A randomized clinical trial to assess the effectiveness of prone position on cardiorespiratory outcomes among infants with respiratory distress


1 Faculty of Nursing, Jamia Hamdard, New Delhi, India
2 Faculty of Nursing, St. Stephen's Hospital, New Delhi, India

Date of Web Publication19-May-2016

Correspondence Address:
Prerna Sharma
A Block, 4/8, Near Pusta Road, West Karawal Nagar, New Delhi - 110 094
India
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/2394-7438.182725

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  Abstract 

Aims: The aim of this study was to assess for and compare the effect of prone and supine position on cardiorespiratory outcome among infants with respiratory distress (RD) and to screen any complications during positioning. Settings and Design: Quantitative experimental research approach was adopted for the study. It was a randomized clinical trial with parallel group design conducted in pediatric unit of St. Stephen's Hospital, Delhi. Methods: The population comprised infants with RD having a score of 3–7 Downes score system scale admitted in pediatric unit. Participants were randomized and treatment allocation by permuted block design. No blinding was done. Pre- and post-intervention cardiorespiratory outcomes (heart rate [HR], respiratory rate [RR], oxygen saturation level (SpO2), and RD) were assessed. Statistical Analysis Used: SPSS version 20 was used for our analysis. Descriptive and inferential statistics was used for the analysis. Results: Total sample size included 60 infants with RD, 30 in each group (prone and supine position). The analysis showed that both intervention group had led to an improvement in HR, RR, SpO2, and RD with both group, but the effectiveness was more among the infants receiving prone position as evidenced by the pre- and post-intervention mean changes for all the variables (HR, RR, SpO2, and RD). Conclusions: The present study revealed that the introduction of prone position leads to an improvement in HR, RR, SpO2, and RD among infants with RD, without any complications such as apnoea or vomiting as compared to supine position.

Keywords: Cardiorespiratory outcome, prone position, respiratory distress, supine position


How to cite this article:
Sharma P, Arora S, Sarkar S, Puliyel J. A randomized clinical trial to assess the effectiveness of prone position on cardiorespiratory outcomes among infants with respiratory distress. MAMC J Med Sci 2016;2:81-8

How to cite this URL:
Sharma P, Arora S, Sarkar S, Puliyel J. A randomized clinical trial to assess the effectiveness of prone position on cardiorespiratory outcomes among infants with respiratory distress. MAMC J Med Sci [serial online] 2016 [cited 2019 Nov 12];2:81-8. Available from: http://www.mamcjms.in/text.asp?2016/2/2/81/182725


  Introduction Top


Every family looks forward to the birth of a healthy newborn. It is an exciting time with so much to enjoy though in some cases, unexpected difficulties and challenges occur along the way. Respiratory distress (RD) in infancy is a challenging problem. It accounts for significant morbidity and mortality. Many of the complications of RD are preventable and early recognition and prompt management are required. Despite the implementation of supportive treatment measures, mortality rates for acute respiratory distress syndrome continue to be high, ranging from 35% to 45%, depending on the center.[1] Causes of under-five mortality rate according to the WHO are depicted in [Figure 1].
Figure 1: Under-five mortality according to the WHO 2013 statistics

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Facility-based Integrated Management of Neonatal and Childhood Illness (F-IMNCI)[2] (2015) as per census 2011, the share of children (0–6 years) accounts for 13% of the total population in the country. An estimated 1.27 million children die every year before completing 5 years of age. However, 81% of under-five child mortalities take place within 1 year of the birth which accounts for nearly 1.05 million infant deaths, whereas 57% of under-five deaths take place within first 1 month of life accounting for 0.73 million neonatal deaths every year in the country. F-IMNCI is the integration of the facility-based care package with the IMNCI package, to empower the health personnel with the skills to manage newborn and childhood illness at the community level as well as at the facility.

As newborn infants exhibit physiological and behavioral signs of pain and stress that can be recognized by healthcare professionals, pharmacological and nonpharmacological resources may be employed in the Neonatal Intensive Care Unit (NICU) to manage such conditions.[3],[4],[5] In this regard, appropriate positioning is considered an important nonpharmacological intervention in premature newborns admitted to NICU,[6],[7] and according to some studies, the frequency of stress behaviors is lower when infants are placed in the prone position.[8],[9]

The simple positioning of low birth weight infants may prevent these dangers to the neonatal life. Prone and head tilted up 45° positions are researched in improving the efficacy of oxygenation. Positioning of infants is a simple and safe therapeutic maneuver with prompt and demonstrable benefit. Early in hospitalization, the prone position is best for preterm infants and result in improved oxygenation, better tolerated feedings, and more organized sleep-rest patterns. Infants exhibit less physical activity and energy expenditure when placed in the prone position.[10]

In 2001, Kornecki et al.[11] concluded that oxygenation was found to be significantly superior in the prone position than in the supine position. They justified that prone ventilation however is not yet a standard practice and it is reasonable to assume that optimized initial ventilation would lead to improved results in terms of shortened duration of ventilation and improved survival.

Blanch et al. in 1997[12] reported improved oxygenation after they had been placed in the prone position for 60–90 min. The infants also showed an improvement in the respiratory mechanics that was reflected by an increase in thoracopulmonary compliance and a decrease in shunt.

A study performed by Taccone et al.[13] suggests a nonsignificant 10% difference in mortality favoring the prone group, and a significantly greater proportion of infants in the prone group experienced at least 1 complication as compared to the supine group. They concluded that the rate of complications was almost 3 times greater in the prone group than in the supine group.

In spite of the volume of literature, a quick survey of intensive care unit (ICU) nursing staff revealed that they were not aware about importance of prone positioning in infants, and it was not practiced in most of the hospitals. The literature is available on prone ventilation but there is less data available on effect of prone sleeping during nursery care. Sudden infant death syndrome (SIDS) was related to prone body positioning during sleep.

The SIDS risk may be small compared to benefits on ventilation in children with RDS who do not need ventilation. Hence, the author felt the need to study the effect of prone position among infants with RD.

Objectives

  1. To assess and compare the effect of prone and supine position on heart rate (HR), respiratory rate (RR), oxygen saturation level (SpO2), and RD among infants with RD
  2. To assess the infants for any complication resulting from prone and supine positioning.



  Methods Top


Description of trial design

The study was approved by the institutional ethics committee and informed consent was obtained from the patients. The quantitative experimental research approach was adopted in the present study. The present study was a randomized clinical trial with parallel group design for 1 month. In the present study, the independent variable was prone or supine position given to infants. The dependent variables in the present study were HR, RR, SpO2, and RD.

Participants

A prior assessment was made to assess all the infants with RD on the basis of screening sheet. Exclusion criteria were (1) infants with invasive ventilator support, (2) infants having any congenital malformation of airway, (3) infants with any congenital heart disease, (4) infants with foreign body aspiration, (5) infants with upper airway obstruction, (6) infants with any surgical condition in which prone position is contraindicated, and (7) infants whose parents are not willing to participate in the study.

Study setting and location

The present study was conducted in pediatric unit (NICU, Pediatric Intensive Care Unit, and post-ICU) of St. Stephen's Hospital, Delhi.

Interventions

  1. The infants were screened based on inclusion and exclusion criteria and then enrolled in the study
  2. Infant's parents were assured of confidentiality of their data
  3. The purpose of the study was explained to parents
  4. Patient information sheet was given to parents and consent obtained
  5. Randomization of sample was done by permuted block system
  6. Then, the total sample was divided into infants receiving prone position and supine position
  7. Collection of baseline demographic variable with the help of structured interview schedule was done for both the groups. Before the administration of prone position, preintervention of physiological parameters, namely, HR, RR, SpO2, RD, complication detecting checklist was assessed for parameters like agitated cry, lethargy, vomiting, and apnea
  8. Those randomized to receive, prone position was given for 2 h. They were place prone on their abdomen with head turned to one side on an even surface
  9. At 1st h, again complication detecting checklist was assessed on infants in prone position. After 2 h, physiological parameters, namely, HR, RR, SpO2, RD, and complication detecting checklist was assessed for parameters (agitated cry, lethargy, vomiting, and apnea)
  10. In Infants receiving supine position as a standard treatment and physiological parameters, namely, HR, RR, SpO2, RD, and complication detecting checklist were assessed at pre-intervention 0 min and 1st h. Likewise, parameters for parameters (agitated cry, lethargy, vomiting, and apnea), were also assessed.
  11. After 2 h, again all the parameters were assessed.



  Other Information Top


Registration

Before starting the data collection, the researcher has registered the trial in the Clinical Trials Registry-India (CTRI) hosted at the ICMR's National Institute of Medical Statistics, and the CTRI No. is CTRI/2015/12/006414.

Protocol for data collection

  1. Self-introduction and establishment of rapport with parents was done
  2. Provision of conducive environment by providing a separate room for the interview schedule was given for data collection
  3. The infants were screened based on inclusion and exclusion criteria and then enrolled for a study
  4. Infant's parents were assured of confidentiality of their data
  5. The purpose of study was explained to parents
  6. Patient Information sheet was given to parents and consent obtained
  7. Randomization of sample was done by permuted block system
  8. In the present study, total sample size, i.e. 60, was divided into 6 blocks by computerized random number generator by www.randomization.com. Each block had ten intervention (prone/supine) sequences. Each intervention, i.e., prone or supine was entered in a sealed envelope, and then the intervention was given by the researcher according to the intervention written in the sealed envelopes and the sequence of infant
  9. Then the total sample was divided into infants receiving prone position and supine position
  10. Collection of baseline demographic variable with the help of structured interview schedule was done for both the groups
  11. In infants before the administration of prone position, preintervention of physiological parameters, namely, HR, RR, (SpO2, RD and complication detecting checklist was assessed for parameters (agitated cry, lethargy, vomiting, and apnea). Than prone position was given for 2 h
  12. Prone position infants were put on their abdomen with head turned to one side on an even surface
  13. At 1st h, again complication detecting checklist was assessed on infants in prone position
  14. After 2 h, postintervention of physiological parameters, namely, HR, RR, SpO2, RD, and complication detecting checklist was assessed for parameters (agitated cry, lethargy, vomiting and apnea)
  15. Infants who were receiving supine position as a standard treatment was continued, and preintervention of physiological parameters, namely, HR, RR, SpO2, RD, and complication detecting checklist was assessed at 0 min and 1st h for parameters (agitated cry, lethargy, vomiting and apnea). After 2 h, again postintervention was done for the same parameters.



  Outcomes Top


Primary outcome, it was hypothesized that there will be significant difference of HR, RR, SPO2 and RD among infants receiving prone position than supine position at 0.05 level of significance.

A structured interview schedule to assess the demographic data, cardiorespiratory proforma for the assessment of physiological parameters, pulse oximeter was used to monitor oxygen saturation of patient's blood and changes in blood volume in the skin, Downes scoring system to assess RD score of infants designed to objectively assess RD clinically by observing five variables, i.e. cyanosis, retraction, grunting, air entry and RR, and complication detecting checklist for observing any complication during and after position.

Interrater reliability was used along with the researcher and resident on duty, and pulse oximeter calibration was done by biomedical personnel on October 11, 2015 before data collection.

Sample size

For sample size calculation, power analysis was performed by the researcher with the help of the previous study, i.e. Eghbalian [14] data; they did a study to determine the effectiveness of prone position on oxygen saturation among premature infant with RD. They have concluded in their study that oxygen saturation was significantly higher in prone position than supine. For sample size calculation, power analysis was done by using the formula:

Effect size (d) = µ1− µ2

where µ1– Mean of population of prone position

µ2– Mean of population of supine

σ – Population standard deviation

µ1 is 92 and µ2 is 90. Here, the authors looked for difference in saturation of 2%, assuming relation in prone and supine.

The average standard deviation is 2.25.

When the data were substituted in the above formula, effect size was calculated as 0.80.

Hence, effect size was 0.80 at 0.05 level of significance, and the calculated sample size was 25 in each group. For the present study, the final sample size was kept 60 to prevent attrition.

Randomization

Randomization sequence was generated with the help of www.randomization.com.

Randomization: Allocation concealment mechanism

In the present study, total sample size, i.e. 60, was divided into 6 blocks by computerized random number generator by www.randomization.com. Each block had ten intervention (prone or supine position) sequences. Each intervention, i.e., prone or supine was entered in a sealed envelope, and then the intervention was given by researcher according to the intervention was given to infants as per the sequence of treatment in sealed envelope.

It was an open label study.

There was no similarity of intervention.

Statistical method

Data were analyzed using SPSS R in circle (SOSOFTONIC INTERNATIONAL S.A. version 20). The level of significance was kept at 0.05 level. The two groups were homogeneous with regard to all demographic variables as analyzed by Chi-square and Fisher's exact tests. Cardiorespiratory outcomes, namely, HR, RR, and SpO2 and RD with regard to pretest as analyzed by paired and unpaired t–tests were assessed.

No additional analysis was used. Beside those planned earlier.


  Results Top


Participant flow: In each group, 30 infants with RD were allocated to assess primary outcomes.

There were no losses and no exclusion in the study.

Recruitment

Formal ethical clearance was obtained from the Ethical Committe of St. Stephen Hospital and Jamia Hamdard Review Board. Data were collected from October 12, 2015, to November 5, 2015. There was neither attrition nor loss.

The trial was completed and was not stopped in between.

Baseline data

The two groups were homogeneous with regard to all demographic variables except for age [Table 1] and cardiorespiratory outcomes, namely, HR, RR, and SpO2 and RD with regard to pretest as analyzed by student t-test [Table 2].
Table 1: Comparison of demographic variables in both the groups

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Table 2: Mean, standard deviation, standard error of mean, independent t-test computed to compare pretest HR, RR, SpO2, and respiratory distress among infants between prone position and supine position (n1+n2=60)

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For each group, number of participants (denominator) included in each analysis was 30, and the analysis was done by originally assigned groups.

Outcomes and estimation

The analysis shows that the introduction of prone position had led to an improvement in HR, RR, SpO2, and RD among infants with RD. Although improvement was also seen among infants receiving supine position [Table 3], the effectiveness was more in the infants receiving prone position as evidenced by the pre- and post-intervention mean changes for all the variables (HR, RR, SpO2, and RD) as compared to supine position at significance of 0.05 level [Table 4]. Agitated cry was present in the initial period of intervention but it was reduced after 2 h in prone position, and there was no significant change in lethargy during positioning. Vomiting was not observed in either group. In infants receiving supine position, 2 children had apnea episode but it was self-limiting because of their preterm gestation [Table 5]. The study concluded that the prone position was effective in improving the cardiorespiratory outcome and RD. Improvement was also seen in cardiorespiratory outcomes and RD among infants with supine position, but the post mean for all the variables was more among infants who received prone position.
Table 3: Comparison of the pre- and post-intervention observation for cardiorespiratory outcome and respiratory distress among infants with respiratory distress in prone and supine position

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Table 4: Comparison of the postintervention observation for cardiorespiratory outcome and respiratory distress among infants with respiratory distress in prone and supine position (n1+n2=60)

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Table 5: Frequency and percentage distribution of infants receiving prone position and supine position according to the complication at 0 min, 1st h, and 2nd h (n1+n2=60)

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There were no other analyses performed, including subgroup analyses and adjusted analyses, distinguishing prespecified from exploratory.

Harms

There was no episode of any harmful incident for infant.


  Discussion Top


The present study aimed at the assessment of cardiorespiratory outcomes, namely, HR, RR, SpO2, and RD of the infants with RD. Study findings have concluded that HR improved and there was no episode of apnea or bradycardia during prone positioning. The findings were not similar in the study done by Ellsworth et al.,[15] who did an observational study to assess the effect of prone position on infants at risk for significant morbidity, mortality including SIDS and concluded that prone position cause bradycardia in neonates.

The results in the present study were similar to the study by Das et al.,[16] who did a comparative study to analyze the effect of prone versus supine position on oxygen saturation in neonates with RD. All the newborns with RD were kept in supine position for 3 h, and then they were kept in prone position for 6 h and oxygen saturation and RR were measured with 2 h interval, respectively, for 6 h. These authors concluded that prone position improves SpO2 and decreases RD as compared to supine position in neonates with RD.

The present study had same findings as that of Ghorbani et al.,[17] who did a crossover study to compare supine and prone positions on RR of premature infants with RDS who were treated using nasal continuous positive airway pressure. They concluded that prone position could decrease infants HR and RR, so that they support prone positioning for premature infants. Improvement in HR was seen which was not present in the previous study done by Ma et al.,[18] who did a prospective study to evaluate the cardiovascular response to short-term prone positioning in neonates. After the final result, they have concluded that HR has no association with prone position.

In our study, there was improvement in cardiorespiratory outcome after prone position; however, the results are different from the findings of the study carried out by Bredemeyer and Foster,[19] who concluded that there is insufficient evidence to determine the role of body positioning on apnea, bradycardia, oxygen desaturation, and oxygen saturation.

The present study showed that there is significant difference of RR and RD among the infants who have received prone position. It has been seen in previous studies that there is association between prone position and RR among infants and prone position improve lung function by optimizing breathing strategy Gouna et al.[20]

The index study has shown that prone position leads to improvement in oxygen saturation among infants which was also seen in the previous studies.[21],[22],[23],[24]

The study did not find any relationship between prone position and mortality rate, which has been seen in previous studies [25],[26],[27] that have concluded that prone position improves oxygenation in infants with adult RDS, and in infants with higher illness severity, it also may reduce mortality and may cause significant improvement in survival.


  Conclusions Top


The present study revealed that the introduction of prone position leads to an improvement in HR, RR, SpO2, and RD among infants with RD, without any complications such as apnoea or vomiting as compared to the supine position.

Limitation

Limitation of the study is that it was confined to a specific geographical area (Delhi), specific disease condition RD, and there was no blinding which imposes limit for generalization.

 
  References Top

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Phua J, Badia JR, Adhikari NK, Friedrich JO, Fowler RA, Singh JM, et al. Has mortality from acute respiratory distress syndrome decreased over time? A systematic review. Am J Respir Crit Care Med 2009;179:220-7.  Back to cited text no. 1
    
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National Health Mission-Ministry of Health and Family Welfare. 2015 Guidelines. Available from: http://www.nrhm.gov.in/nrhm-components/rmnch-a/child./guidelines.html. [Last uploaded on 2015 Aug 25; Last cited on 2015 Sep 25].  Back to cited text no. 2
    
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Cândia MF, Osaku EF, Leite MA, Toccolini B, Costa NL, Teixeira SN, et al. Influence of prone positioning on premature newborn infant stress assessed by means of salivary cortisol measurement: Pilot study. Rev Bras Ter Intensiva 2014;26:169-75.  Back to cited text no. 3
    
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Gitau R, Modi N, Gianakoulopoulos X, Bond C, Glover V, Stevenson J. Acute effects of maternal skin-to-skin contact and massage on saliva cortisol in preterm babies. J Reprod Infant Psychol 2002;20:83-8.  Back to cited text no. 4
    
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Boyer K, Johnston C, Walker CD, Filion F, Sherrard A. Does sucrose analgesia promote physiologic stability in preterm neonates? Biol Neonate 2004;85:26-31.  Back to cited text no. 5
    
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Takahashi Y, Tamakoshi K, Matsushima M, Kawabe T. Comparison of salivary cortisol, heart rate, and oxygen saturation between early skin-to-skin contact with different initiation and duration times in healthy, full-term infants. Early Hum Dev 2011;87:151-7.  Back to cited text no. 6
    
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Byers JF. Components of developmental care and the evidence for their use in the NICU. MCN Am J Matern Child Nurs 2003;28:174-80.  Back to cited text no. 7
    
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Grenier IR, Bigsby R, Vergara ER, Lester BM. Comparison of motor self-regulatory and stress behaviors of preterm infants across body positions. Am J Occup Ther 2003;57:289-97.  Back to cited text no. 8
    
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Chang YJ, Anderson GC, Lin CH. Effects of prone and supine positions on sleep state and stress responses in mechanically ventilated preterm infants during the first postnatal week. J Adv Nurs 2002;40:161-9.  Back to cited text no. 9
    
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Brower RG, Matthay MA, Wheeler A. The Acute Respiratory Distress Syndrome Network. Ventilation with lower tidal volumes as compared with traditional tidal volumes for acute respiratory distress syndrome. N Engl J Med 2000;342:1301-8.  Back to cited text no. 10
    
11.
Kornecki A, Frndova H, Coates AL, Shemie SD. Prone position is best for acute respiratory failure. AAP Grand Rounds 2001;5:48-9.  Back to cited text no. 11
    
12.
Blanch L, Mancebo J, Perez M, Martinez M, Mas A, Betbese AJ, et al. Short-term effects of prone position in critically ill patients with acute respiratory distress syndrome. Intensive Care Med 1997;23:1033-9.  Back to cited text no. 12
    
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Taccone P, Pesenti A, Latini R, Polli F, Vagginelli F, Mietto C, et al. Prone positioning in patients with moderate and severe acute respiratory distress syndrome: A randomized controlled trial. JAMA 2009;302:1977-84.  Back to cited text no. 13
    
14.
Eghbalian F. A comparison of supine and prone positioning on improves arterial oxygenation in premature neonates. J Neonatal Perinatal Med 2014;7:273-7.  Back to cited text no. 14
    
15.
Ellsworth MA, Ulrich TJ, Carey WA, Colby CE, Ackerman MJ. QTc interval prolongation and severe apneas associated with a change in infant positioning. Pediatrics 2013;132:e1690-3.  Back to cited text no. 15
    
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Das H, Shaikh S, Kella N. Effect of prone versus supine position on oxygen saturation in patients with respiratory distress in neonates. Pak J Med Sci 2011;27:1098-101.  Back to cited text no. 16
    
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Ghorbani F, Asadollahi M, Valizadeh S. Comparison the effect of sleep positioning on cardiorespiratory rate in noninvasive ventilated premature infants. Nurs Midwifery Stud 2013;2:182-7.  Back to cited text no. 17
    
18.
Ma M, Noori S, Maarek JM, Holschneider DP, Rubinstein EH, Seri I. Prone positioning decreases cardiac output and increases systemic vascular resistance in neonates. J Perinatol 2015;35:424-7.  Back to cited text no. 18
    
19.
Bredemeyer SL, Foster JP. Body positioning for spontaneously breathing preterm infants with apnoea. Cochrane Database Syst Rev 2012;6:CD004951.  Back to cited text no. 19
    
20.
Gouna G, Rakza T, Kuissi E, Pennaforte T, Mur S, Storme L. Positioning effects on lung function and breathing pattern in premature newborns. J Pediatr 2013;162:1133-7.  Back to cited text no. 20
    
21.
Mora-Arteaga JA, Bernal-Ramírez OJ, Rodríguez SJ. The effects of prone position ventilation in patients with acute respiratory distress syndrome. A systematic review and metaanalysis. Med Intensiva 2015;39:359-72.  Back to cited text no. 21
    
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Lal S, Abassi AS, Lal S, Jamro S. Effects of position on oxygen saturation in acute respiratory distress in neonates. J Surg Pak (International) 2013;18:179-81.  Back to cited text no. 22
    
23.
Balaguer A, Escribano J, Roqué i Figuls M, Rivas-Fernandez M. Infant position in neonates receiving mechanical ventilation. Cochrane Database Syst Rev 2013;3:CD003668.  Back to cited text no. 23
    
24.
Gillies D, Wells D, Bhandari AP. Positioning for acute respiratory distress in hospitalised infants and children. Cochrane Database Syst Rev 2012;7:CD003645.  Back to cited text no. 24
    
25.
Alsaghir AH, Martin CM. Effect of prone positioning in patients with acute respiratory distress syndrome: A meta-analysis. Crit Care Med 2008;36:603-9.  Back to cited text no. 25
    
26.
Baijal N, Puliyel J, Beri RS, Sreenivas V. Prone versus supine position in mechanically ventilated children. J Pediatr Child Health 2006;42:A8.  Back to cited text no. 26
    
27.
Sawhney A, Kumar N, Sreenivas V, Gupta S, Tyagi V, Puliyel JM. Prone versus supine position in mechanically ventilated children: A pilot study. Med Sci Monit 2005;11:CR235-240.  Back to cited text no. 27
    


    Figures

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    Tables

  [Table 1], [Table 2], [Table 3], [Table 4], [Table 5]



 

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