Intervention Review

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Infant position in neonates receiving mechanical ventilation

  1. Albert Balaguer1,*,
  2. Joaquin Escribano2,
  3. Marta Roqué i Figuls3,
  4. May Rivas-Fernandez4

Editorial Group: Cochrane Neonatal Group

Published Online: 28 MAR 2013

Assessed as up-to-date: 15 DEC 2012

DOI: 10.1002/14651858.CD003668.pub3

How to Cite

Balaguer A, Escribano J, Roqué i Figuls M, Rivas-Fernandez M. Infant position in neonates receiving mechanical ventilation. Cochrane Database of Systematic Reviews 2013, Issue 3. Art. No.: CD003668. DOI: 10.1002/14651858.CD003668.pub3.

Author Information

  1. 1

    Universitat Internacional de Catalunya, Department of Pediatrics. Hospital General de Catalunya., Barcelona, CATALONIA, Spain

  2. 2

    Hospital Universitari St Joan de Reus, Department of Pediatrics, Reus, Catalonia, Spain

  3. 3

    CIBER Epidemiología y Salud Pública (CIBERESP), Spain, Iberoamerican Cochrane Centre, Institute of Biomedical Research (IIB Sant Pau), Barcelona, Barcelona, Catalunya, Spain

  4. 4

    Hospital General de Cutalunya, Pediatric Service, Barcelona, Spain

*Albert Balaguer, Department of Pediatrics. Hospital General de Catalunya., Universitat Internacional de Catalunya, C/ Pedro I Pons, 1, Sant Cugat de Vallés, Barcelona, CATALONIA, 08195, Spain. abalaguer@uic.es. balaguer.albert@gmail.com.

Publication History

  1. Publication Status: New search for studies and content updated (no change to conclusions)
  2. Published Online: 28 MAR 2013

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Characteristics of included studies [ordered by study ID]
Aly 2008

MethodsRandomised parallel controlled trial

Method of randomisation: not stated

Infant’s position: supine or lateral alternant

Blinding of intervention: no

Complete follow-up: no. Nineteen patients dropped out of the study because of early death (15) or early extubation (four); group is unclear

Blinding of outcome measurement: simple for tracheal culture


ParticipantsSample size 60 (from a study of 79, data from 15 were discarded by the authors of this study because death and 5 because early extubation)

Gestational age at birth: 31.6 - 39.1 weeks; supine (35.4 ± 4.2), lateral (35.3 ± 3.3)

Age: 0 - 2 days

Associated conditions: not stated

Exclusion: congenital sepsis or pneumonia or congenital anomalies. If they could not be maintained on mechanical ventilation for 5 full days


InterventionsSupine versus lateral (alternating left or right every 2 hours)

Co-interventions: not stated


OutcomesArterial PCO2

Other outcomes not used in this review:culture of tracheal aspirated. Ventilator parameters: FiO2, PIP, PEEP, IMV. Blood gas data: pH, HCO3 level. Laboratory data:WBC count, haemoglobin level, platelet count


Notes


Risk of bias

BiasAuthors' judgementSupport for judgement

Random sequence generation (selection bias)Unclear riskMethod of randomisation: not stated

Allocation concealment (selection bias)Unclear riskMethod of allocation: not stated

Blinding of participants and personnel (performance bias)
All outcomes
High riskBlinding of intervention was not possible

Incomplete outcome data (attrition bias)
All outcomes
High riskNumber randomised in each group is unclear, no ITT

Selective reporting (reporting bias)Unclear riskStudy did not pre-specify primary outcomes so it is unclear

Other biasLow risk

Antunes 2003

MethodsRandomised parallel controlled trial

Method of randomisation: drawing lots in the form of sealed envelopes defining the infant´s position: supine or prone

Blinding of intervention: no

Complete follow-up: no. One patient did not complete the protocol but no stated reason

Blinding of outcome measurement: no


ParticipantsSample size 42

Gestational age at birth: 24 - 33 weeks; supine (29.3 ± 2.57), prone (29.6 ± 2.46)

Age: Supine 2 - 50 days 4 (2; 10) quartiles (Q1; Q3)

Prone: 2 - 37 days 11 (3; 25) quartiles (Q1;Q3). On mechanical ventilation due to a unspecified cause during the first week of life for a period > 48 hours. In stable condition when weaning process was decided

Associated conditions: not stated

Exclusion:

a) congenital defects or clinical or surgical conditions which make the randomised position impossible to maintain

b) Failure to obtain the all information of research protocol

c) Inadvertent violation of research protocol or the newborn remaining in a position other than that prescribed by the study for more than an hour per day


InterventionsProne versus supine

(from the start of weaning of VA until his/her extubation, except 3 hours a day in the newborns allocated to the prone position)


OutcomesDuring intervention:

Oxygen saturation of haemoglobin by pulse oximetry (while changing ventilator parameters)

Respiratory and cardiac rate

Number of desaturation episodes (SaO2 values of less than 90% requiring a temporary increase in FiO2)

Ventilator parameters: FiO2, PIP and respiratory rate, (average values for each day)

Atelectasis (based on the thorax radiography findings, performed for difficult to wean patients and during the first 12 hours post-extubation for all infants)

Apnea (defined as an inspiration pause of more than 20 seconds duration or of lesser duration, but associated with bradycardia and/or cyanosis)

Mechanical ventilation weaning duration

Outcomes after intervention

Weaning complication: atelectasis. Need for reintubation (during 48 hours post-extubation)


Notes


Risk of bias

BiasAuthors' judgementSupport for judgement

Random sequence generation (selection bias)Low risk

Allocation concealment (selection bias)Low risk

Blinding of participants and personnel (performance bias)
All outcomes
High riskBlinding of intervention was not possible

Incomplete outcome data (attrition bias)
All outcomes
High riskOne drop-out for no reason explained, no ITT

Selective reporting (reporting bias)Unclear riskStudy did not pre-specify primary outcomes so it is unclear

Other biasLow risk

Bjornson 1992

MethodsRandomised crossover controlled trial

Method of randomisation: not stated

Blinding of intervention: no

Complete follow-up: no. Two newborns needed changes in the ventilatory parameters during the study and could not complete the 9 sessions prescribed (one newborn: 6 sessions, another one: 7)

Blinding of outcome measurement: no


ParticipantsSample size 4

Gestational age at birth: 24 - 30 weeks (26.50 ± 2.08)

Age: 9 - 24 days (10.75 ± 2.50)

On conventional ventilation since birth due to RDS

Associated conditions: 2 sepsis, 1 patent ductus arteriosus

Exclusion: major congenital defects, cardiac anomalies (other than patent ductus arteriosus), major intraventricular haemorrhages, maternal substance abuse


InterventionsProne versus supine

Prone versus lateral right

Supine versus lateral right

Co-interventions (similar across comparison): 1 newborn received sedation, 1 corticoids, 2 treatment for sepsis (one of them underwent a surgical ligation of a patent ductus arteriosus)


OutcomesOxygen saturation of haemoglobin by pulse oximetry (SpO2)


NotesResults extracted from graph


Risk of bias

BiasAuthors' judgementSupport for judgement

Random sequence generation (selection bias)Unclear riskMethod of randomisation: not stated

Allocation concealment (selection bias)Unclear riskMethod of allocation: not stated

Blinding of participants and personnel (performance bias)
All outcomes
High riskBlinding of intervention was not possible

Incomplete outcome data (attrition bias)
All outcomes
High riskNo complete follow-up for reason explained, no ITT

Selective reporting (reporting bias)Unclear riskStudy did not pre-specify primary outcomes so it is unclear

Other biasLow risk

Bozynski 1988

MethodsRandomised crossover controlled trial

Method of randomisation: not stated

Blinding of intervention: no

Complete follow-up: yes

Blinding of outcome measurement: no


ParticipantsSample size 18 gestational age at birth: 24 - 30 weeks (27.5)

Age > 14 days (31)

On mechanical ventilation (IMV) due to CLD. In stable condition

Exclusion: asymmetric lung disease or any other major problem (including patent ductus arteriosus)


InterventionsLateral right versus supine

Lateral left versus supine

Lateral left versus lateral right

Co-interventions (similar across comparison): furosemide in 12 newborns, spironolactone + thiazide in seven


OutcomesTranscutaneous PO2 (tcPO2) and transcutaneous PCO2 (tcPCO2): only means and range (the review authors extracted the results from a graph)
Other outcomes not used in this review: sleep state


NotesResults extracted from graph


Risk of bias

BiasAuthors' judgementSupport for judgement

Random sequence generation (selection bias)Unclear riskMethod of randomisation: not stated

Allocation concealment (selection bias)Unclear riskMethod of allocation: not stated

Blinding of participants and personnel (performance bias)
All outcomes
High riskBlinding of intervention was not possible

Incomplete outcome data (attrition bias)
All outcomes
Low risk

Selective reporting (reporting bias)Unclear riskStudy did not pre-specify primary outcomes so it is unclear

Other biasLow risk

Chang 2002

MethodsRandomised crossover controlled trial
Randomisation method: randomisation in blocks by a third person to ensure balanced combinations of positions and finally using an identification number in a sealed envelope

Blinding of intervention: no

Complete follow-up: no. 10 patients (4 in prone, 6 in supine) did not complete the 2-hour protocol in the same position because of the need for interventions (airway suctioning, etc), then equal duration of a selected similarly distributed length of time was used for analysis

Blinding of outcome measurement: no


ParticipantsSample size 28.

Gestational age at birth: 25 - 36 weeks (29.5 ± 3.5). Age < 7 days (38 ± 31). On mechanical ventilation (IMV ) due to RDS in 20 cases, the remaining 8 due a unspecified cause. In relatively stable condition (no need for frequent change in ventilator settings)

Associated conditions: not stated

Exclusion: known congenital defects or newborns treated with sedatives


InterventionsProne versus supine

Co-interventions were similar across comparison: Surfactant in 18 newborns


OutcomesOxygen saturation of haemoglobin by pulse oximetry (SpO2) as continuous variable, number of desaturation episodes and their duration

Motor activity


Notes


Risk of bias

BiasAuthors' judgementSupport for judgement

Random sequence generation (selection bias)Low risk

Allocation concealment (selection bias)Low risk

Blinding of participants and personnel (performance bias)
All outcomes
High riskBlinding of intervention was not possible

Incomplete outcome data (attrition bias)
All outcomes
High riskNo complete follow-up for reason explained, no ITT

Selective reporting (reporting bias)Unclear riskStudy did not pre-specify primary outcomes so it is unclear

Other biasLow risk

Crane 1990

MethodsRandomised crossover controlled trial

Method of randomisation: not stated

Blinding of intervention: no

Complete follow-up: no. Only 14 patients were included finally in the study (data from 5 were not used because excessive tcPCO2/PaCO2 difference or inaccurate calibration)

Blinding of outcome measurement: no


ParticipantsSample size: 14 (from a study of 19, data from 5 were discarded by the authors of this study because excessive tcPCO2/PaCO2 difference or inaccurate calibration)

Gestational age at birth: 24 - 36 weeks (31±3). Age: 20 - 72 hr. On mechanical ventilation (IMV) due to RDS. Associated conditions: the only information is that none had evidence of persistent pulmonary hypertension or systemic arterial hypotension

Exclusion: not stated


InterventionsProne versus supine

Prone versus lateral right

Supine versus lateral right

Co-interventions: not stated


OutcomesTranscutaneous PCO2 (tcPCO2)


Notes


Risk of bias

BiasAuthors' judgementSupport for judgement

Random sequence generation (selection bias)Unclear riskMethod of randomisation: not stated

Allocation concealment (selection bias)Unclear riskMethod of allocation: not stated

Blinding of participants and personnel (performance bias)
All outcomes
High riskBlinding of intervention was not possible

Incomplete outcome data (attrition bias)
All outcomes
Unclear riskNo complete follow-up for reason explained,number randomised in each group is unclear

Selective reporting (reporting bias)Unclear riskStudy did not pre-specify primary outcomes so it is unclear

Other biasLow risk

Fox 1990

MethodsRandomised crossover controlled trial

Method of randomisation: coin toss

Blinding of intervention: no

Complete follow-up: yes

Blinding of outcome measurement: no


ParticipantsSample size 25

Gestational age at birth: 26 - 35 weeks (30.68 ± 2.41). Age: 22 hr - 5 days (55.4 ± 32.17). On respiratory support (IMV or CPAP) due to RDS

Associated conditions: not stated

Exclusion: newborns treated with paralysing drugs


InterventionsProne versus supine

Co-interventions: not stated


OutcomesArterial PO2 (umbilical catheter attached to a monitor)


Notes


Risk of bias

BiasAuthors' judgementSupport for judgement

Random sequence generation (selection bias)Low risk

Allocation concealment (selection bias)Low risk

Blinding of participants and personnel (performance bias)
All outcomes
High riskBlinding of intervention was not possible

Incomplete outcome data (attrition bias)
All outcomes
Low risk

Selective reporting (reporting bias)Unclear riskStudy did not pre-specify primary outcomes so it is unclear

Other biasLow risk

Heaf 1983

MethodsRandomised crossover controlled trial

Method of randomisation: not stated. Only randomised lateral position (left-right), no supine position

Blinding of intervention: no

Complete follow-up: yes

Blinding of outcome measurement: no


ParticipantsSample size: 4 (from a study of 10, only 4 were eligible for this review because of age and need of respiratory support)

Gestational age at birth: not stated (probably term newborns - deduced by the weight)

Age: 2 - 5 days (2.75 ± 1.5)

On respiratory support (IPPV or CPAP) due to unilateral (asymmetrical) lung disease

Associated conditions: 3 congenital diaphragmatic hernia, 1 hypoplastic right lung

Exclusion: not stated


InterventionsGood lung dependent versus good lung uppermost

Co-interventions (similar across comparison): in 3 newborns surgery for congenital diaphragmatic hernia


OutcomesTranscutaneous PO2 (tcPO2) and transcutaneous PCO2 (tcPCO2)


Notes


Risk of bias

BiasAuthors' judgementSupport for judgement

Random sequence generation (selection bias)Unclear riskMethod of randomisation: not stated

Allocation concealment (selection bias)Unclear riskMethod of allocation: not stated

Blinding of participants and personnel (performance bias)
All outcomes
High riskBlinding of intervention was not possible

Incomplete outcome data (attrition bias)
All outcomes
Low risk

Selective reporting (reporting bias)Unclear riskStudy did not pre-specify primary outcomes so it is unclear

Other biasLow risk

Mendoza 1991

MethodsRandomised crossover controlled trial

Method of randomisation: not stated

Blinding of intervention: no

Complete follow-up: 7 patients were excluded from analysis of some lung mechanics for having good spontaneous breaths in neither or only one of the positions

Blinding of outcome measurement: no


ParticipantsSample size: 26 (from a study of 33, data from 7 were excluded from analysis by the authors because those 7 patients did not have good spontaneous breaths in each of the positions studied)

Gestational age at birth: 23 - 33 weeks (mean: 27)

Age: 15 - 138 days (mean: 28)

On mechanical ventilation (IMV) due to RDS needing MV for more than 2 weeks

Exclusion: not stated


InterventionsProne versus supine

Co-interventions (similar across comparison): theophylline


OutcomesTidal volume (TV) in mL/kg (spontaneous breath), minute ventilation (MV) in mL/kg/min.

Other outcomes not used in this review: oxygen saturation of haemoglobin by pulse oximetry (SpO2) - unusable data due to deficiencies in data reporting (mean point estimate without measure of standard deviation); dynamic lung compliance, resistance (expiratory and inspiratory), total work of breathing and heart rate


Notes


Risk of bias

BiasAuthors' judgementSupport for judgement

Random sequence generation (selection bias)Unclear riskMethod of randomisation: not stated

Allocation concealment (selection bias)Unclear riskMethod of allocation: not stated

Blinding of participants and personnel (performance bias)
All outcomes
High riskBlinding of intervention was not possible

Incomplete outcome data (attrition bias)
All outcomes
Unclear riskNo complete follow-up for reason explained, unclear ITT

Selective reporting (reporting bias)Unclear riskStudy did not pre-specify primary outcomes so it is unclear

Other biasLow risk

Mizuno 1995

MethodsRandomised crossover controlled trial

Method of randomisation: not stated

Blinding of intervention: no

Complete follow-up: yes

Blinding of outcome measurement: no


ParticipantsSample size: 6

Gestational age at birth: 23.9 - 26 weeks (24.8 ± 0.9)

Age: ≥ 21 days (47.5 ± 25.9)

On mechanical ventilation (IMV) due to CLD in stable condition and receiving more than 100 mL/kg/day of feeding volume

Associated conditions: not stated

Exclusion: not stated


InterventionsProne versus supine (before and after feeding)

Co-interventions: not stated


OutcomesSpO2, tcPCO2, tidal volume (TV) in mL/kg (spontaneous breath), minute ventilation (MV) in mL/kg/min

Other outcomes not used in this review: the aforementioned measured after feeding; and spontaneous respiratory rate and heart rate measured before and after feeding


Notes


Risk of bias

BiasAuthors' judgementSupport for judgement

Random sequence generation (selection bias)Unclear riskMethod of randomisation: not stated

Allocation concealment (selection bias)Unclear riskMethod of allocation: not stated

Blinding of participants and personnel (performance bias)
All outcomes
High riskBlinding of intervention was not possible

Incomplete outcome data (attrition bias)
All outcomes
Low risk

Selective reporting (reporting bias)Unclear riskStudy did not pre-specify primary outcomes so it is unclear

Other biasLow risk

Mizuno 1999

MethodsRandomised crossover controlled trial

Method of randomisation: not stated

Blinding of intervention: no

Complete follow-up: yes

Blinding of outcome measurement: no


ParticipantsSample size: 7

Gestational age at birth: 25.7 - 27.7 weeks (26.5 ± 0.9)

Age: ≥ 28 days (57.4 ± 25.9)

On mechanical ventilation (IMV) due to CLD in stable condition and receiving more than 100 mL/kg/day of feeding volume

Associated conditions: not stated

Exclusion: not stated


InterventionsProne versus supine (before, during and after feeding)

Co-interventions: not stated


OutcomesSpO2, tcPCO2, tidal volume (TV) in mL/kg (spontaneous breath), minute ventilation (MV) in mL/kg/min

Other outcomes not used in this review: the aforementioned measured during and after feeding; and the following measured before, during and after (total Minute ventilation, pulmonary resistance, static compliance, work of breathing for spontaneous breath, spontaneous respiratory rate)


Notes


Risk of bias

BiasAuthors' judgementSupport for judgement

Random sequence generation (selection bias)Unclear riskMethod of randomisation: not stated

Allocation concealment (selection bias)Unclear riskMethod of allocation: not stated

Blinding of participants and personnel (performance bias)
All outcomes
High riskBlinding of intervention was not possible

Incomplete outcome data (attrition bias)
All outcomes
Low risk

Selective reporting (reporting bias)Unclear riskStudy did not pre-specify primary outcomes so it is unclear

Other biasLow risk

Schlessel 1993

MethodsRandomised controlled trial (no crossover)

Method of randomisation: not stated

Blinding of intervention: no

Complete follow-up: yes

Blinding of outcome measurement: no


ParticipantsSample size: 16

Gestational age at birth: ≤ 36 weeks (33.4 ± 1.5)

Age: 5 ± 2 days

On mechanical ventilation (IMV) recovering from RDS in stable condition

Exclusion: patent ductus arteriosus, asymmetric lung disease, pneumothorax, pulmonary interstitial emphysema


InterventionsLateral left versus lateral right (in spite of using a sequence of positions including the supine, that position was not randomised)

Co-interventions: not stated


OutcomesArterial PO2, arterial PCO2, tidal volume (spontaneous breath).

Other outcomes not used in this review: dynamic lung compliance, total pulmonary resistance, inspiratory pulmonary resistance, expiratory pulmonary resistance


Notes


Risk of bias

BiasAuthors' judgementSupport for judgement

Random sequence generation (selection bias)Unclear riskMethod of randomisation: not stated

Allocation concealment (selection bias)Unclear riskMethod of allocation: not stated

Blinding of participants and personnel (performance bias)
All outcomes
High riskBlinding of intervention was not possible

Incomplete outcome data (attrition bias)
All outcomes
Low risk

Selective reporting (reporting bias)Unclear riskStudy did not pre-specify primary outcomes so it is unclear

Other biasLow risk

 
Characteristics of excluded studies [ordered by study ID]

StudyReason for exclusion

Ancora 2009Not randomised

Baird 1991Not randomised
In this study mechanically ventilated patients were mixed with non-ventilated

Curley 2005Age 2.0 years (0.3 - 11.0) (multicentre with Fineman 2006)

Fineman 2006Age 2.1 years (0.3, 8.6) (multicentre with Curley 2005)

Ibrahim 2007Age 8 months - 9.9 years

Itakura 1998Not randomised
This study didn't supply oxygenation data but measured different pulmonary mechanics parameters

McEvoy 1997Not randomised
Study of 55 infants from which only 17 were being mechanically ventilated

Schrod 1993Not randomised

Wagaman 1979Not randomised

Zhu 2010Not randomised for position

 
Characteristics of studies awaiting assessment [ordered by study ID]
Hough 2012

MethodsOBJECTIVES: To investigate the effect of body position on regional ventilation in preterm infants on continuous positive airway pressure ventilatory support using electrical impedance tomography.

DESIGN: Randomised crossover study design

ParticipantsSETTING: Neonatal intensive care unit

PATIENTS: Twenty-four preterm infants on continuous positive airway pressure were compared to six spontaneously breathing preterm infants

InterventionsINTERVENTIONS: Random assignment of the order of the positions supine, prone, and quarter prone

Changes in global and regional lung volume were measured with electrical impedance tomography

OutcomesAlthough there were no differences between positions, regional tidal volume was increased in the posterior compared with the anterior lung (P < .01) and in the right compared with the left lung (P < 0.03) in both the spontaneously breathing infants and in the infants on continuous positive airway pressure. The posterior lung filled earlier than the anterior lung in the spontaneously breathing infants (P < 0.02), whereas in the infants on continuous positive airway pressure the right lung filled before the left lung (P < 0.01). There was more ventilation homogeneity in the infants on continuous positive airway pressure than in the healthy infants (P < 0.01)

NotesAUSTRALIA NEW ZEALAND CLINICAL TRIALS REGISTRY:: ACTRN12606000210572.

 
Comparison 1. Prone versus supine

Outcome or subgroup titleNo. of studiesNo. of participantsStatistical methodEffect size

 1 pO2 (mmHg)150Mean difference (Random, 95% CI)6.24 [2.93, 9.55]

 2 Hb O2Sat (%)490Mean difference (Random, 95% CI)2.77 [1.18, 4.36]

 3 pCO2 (mmHg)354Mean difference (Random, 95% CI)-3.77 [-6.65, -0.89]

 4 Tidal volume (mL/Kg)378Mean difference (Random, 95% CI)0.70 [-0.81, 2.20]

 5 Minute ventilation (mL/Kg/min)378Mean difference (Random, 95% CI)19.80 [-40.54, 80.14]

 6 Patients desaturating298OR Becker-Balagtas (Random, 95% CI)0.18 [0.08, 0.42]

 
Comparison 2. Prone versus lateral

Outcome or subgroup titleNo. of studiesNo. of participantsStatistical methodEffect size

 1 Hb O2 Sat (%)18Mean difference (Random, 95% CI)2.13 [0.33, 3.93]

 2 pCO2 (mmHg)128Mean difference (Random, 95% CI)0.0 [-6.67, 6.67]

 
Comparison 3. Lateral versus supine

Outcome or subgroup titleNo. of studiesNo. of participantsStatistical methodEffect size

 1 pO2 (mmHg)1Mean difference (Random, 95% CI)Subtotals only

    1.1 Lateral Right
136Mean difference (Random, 95% CI)1.1 [-4.78, 6.98]

    1.2 Lateral Left
136Mean difference (Random, 95% CI)3.2 [-4.46, 10.86]

 2 Hb O2 Sat (%)1Mean difference (Random, 95% CI)Subtotals only

    2.1 Lateral Right
18Mean difference (Random, 95% CI)1.39 [-0.60, 3.38]

 3 pCO2 (mmHg)3Mean difference (Random, 95% CI)Subtotals only

    3.1 Lateral Right
264Mean difference (Random, 95% CI)-0.69 [-4.15, 2.78]

    3.2 Lateral Left
136Mean difference (Random, 95% CI)-1.2 [-4.86, 2.46]

    3.3 Alternant lateral
160Mean difference (Random, 95% CI)4.7 [-0.31, 9.71]

 
Comparison 4. Lateral right versus lateral left

Outcome or subgroup titleNo. of studiesNo. of participantsStatistical methodEffect size

 1 pO2 (mmHg)268Mean difference (Random, 95% CI)-0.05 [-6.93, 6.83]

 2 pCO2 (mmHg)268Mean difference (Random, 95% CI)0.41 [-2.01, 2.82]

 3 Tidal volume (mL/Kg)132Mean difference (Random, 95% CI)-0.8 [-1.87, 0.27]

 
Comparison 5. Good lung dependant

Outcome or subgroup titleNo. of studiesNo. of participantsStatistical methodEffect size

 1 pO2 (mmHg)18Mean difference (Random, 95% CI)-7.75 [-31.19, 15.69]

 2 pCO2 (mmHg)18Mean difference (Random, 95% CI)0.75 [-4.16, 5.66]