Suctioning clear amniotic fluid at birth: NLS 5120 (Previous 596)

Conflict of Interest Declaration

The ILCOR Continuous Evidence Evaluation process is guided by a rigorous ILCOR Conflict of Interest policy. The following Task Force members and other authors were recused from the discussion as they declared a conflict of interest: None

The following Task Force member declared an intellectual conflict of interest and this was acknowledged and managed by the Task Force Chairs and Conflict of Interest committees:

• Author Ersdal has published observational studies on use of resuscitation maneuvers including suctioning in low resource settings and was excluded from decisions about inclusion or bias assessment for these studies {Ersdal 2012 869, Ersdal 2018 171, Haug 2020 68, Størdal 2020 e0240520, Mduma 2019 e030572, Msemo 2013 353}.

• Author Rüdiger has published an observational study about suctioning immediately after birth {Konstantelos 2015 777} and was excluded from decisions about inclusion or bias assessment for this study.

CoSTR Citation

Fawke J, Wyllie JP, Udeata E, Rüdiger M, Ersdal H, Rabi Y, Costa-Nobre DT, de Almeida MF, Davis PG, El-Naggar, W, Fabres JG, Foglia EE, Guinsburg R, Hosono S, Isayama T, Kapadia VS, Kawakami MD, Kim HS, Lee HC, Madar RJ, McKinlay CJD, Nakwa FL, Perlman JM, Roehr CC, Schmölzer GM, Sugiura T, Trevisanuto D, Weiner GM, Wyckoff MH, Liley HG.

Suctioning clear amniotic fluid at birth NLS#5120 [Internet]. International Liaison Committee on Resuscitation (ILCOR) Neonatal Life Support Task Force, Available from http://ilcor.org

Methodological Preamble (and Link to Published Systematic Review)

This question was prioritized by ILCOR because although it is a widespread practice, it has not been addressed in a systematic review nor subjected to a GRADE analysis of certainty of evidence by ILCOR previously. A Scoping Review (NLS 596) was conducted in 2019, and found sufficient evidence to justify a systematic review. {Wyckoff 2020 S185} Because a systematic review had not yet been performed, the treatment recommendation in 2020 was that “This treatment recommendation is unchanged from 2010. Routine intrapartum oropharyngeal and nasopharyngeal suctioning for newborn infants with clear or meconium-stained amniotic fluid is no longer recommended”. {Perlman 2010 S516, Wyckoff 2020 S185}

Suctioning of clear amniotic fluid is a very important topic worldwide as it affects many babies including those not requiring/receiving resuscitation. It is very important to know if there is any evidence of benefit or harm as this has been a traditional part of worldwide neonatal care which has not been assessed.

Transition from fetus to newborn involves the baby clearing lung fluid and expanding their lungs with air. Longstanding historical practice has been to use oro/nasopharyngeal suctioning at birth routinely to remove fluids. There have been increasing concerns that this practice may not confer benefit and may have undesirable consequences.

This has lead ILCOR to recommend that “Suctioning immediately after birth, whether with a bulb syringe or suction catheter, may be considered only if the airway appears obstructed or if PPV is required” {Wyckoff 2015 S96}.

The World Health Organisation (WHO) reviewed 3 studies included in this systematic review {Gungor 2005453, Gungor 2006 9, Waltman 2004 32} which examined the effect of oral and nasal suctioning at birth on oxygen saturation (SpO2) levels at 5 minutes of life. {World Health Organization 2017} WHO graded the quality of evidence for this outcome as high. The pooled mean difference (MD) in oxygen saturation levels was 9.8% lower (95% CI -10.2% to -9.4%) in those who underwent oropharyngeal or nasopharyngeal suctioning. There was a significant reduction in the proportion of infants with normal Apgar scores in the suctioning group compared to the group with no suctioning [RR 0.54, 95% CI, 0.29 to 1.00, p=0.049].

The WHO said “In neonates born through clear amniotic fluid who start breathing on their own after birth, suctioning of the mouth and nose should not be performed.” (strong recommendation, high quality of evidence) and “In neonates born through clear amniotic fluid who do not start breathing after thorough drying and rubbing the back 2-3 times, suctioning of the mouth and nose should not be done routinely before initiating positive pressure ventilation. Suctioning should be done only if the mouth or nose is full of secretions.” (strong recommendation, GDG consensus in absence of published evidence). (WHO strong recommendation, based on high quality evidence of lower oxygen saturation and low quality evidence of lower Apgar scores). {World Health Organization 2017}

The continuous evidence process for the creation of Consensus of Science and Treatment Recommendations (CoSTR) started with an ILCOR scoping review of Suctioning clear amniotic fluid during resuscitation in the delivery room (#NLS596) which concluded:

Evidence supporting potential benefits of oropharyngeal/nasopharyngeal suctioning is limited and the practice remains controversial. Oropharyngeal suctioning does not impact liquid removal from the lung. The procedure can have serious side effects. {Wyckoff 2020 S543}

• It is possible that nasopharyngeal suctioning may result in vagal-induced bradycardia as well as increased risk of infection.
• The procedure may take significant time to complete.
• Suctioning may delay initiation of ventilation in nonbreathing infants.
• Newborns who received suctioning compared with a control group had significantly lower oxygen saturation through the first 6 minutes of life and took longer to reach a normal saturation range.
• There is a concern that suctioning may have serious additional consequences, such as irritation to mucous membranes and increased risk of iatrogenic infection, bradycardia, apnoea, hypoxemia and arterial oxygen desaturation, hypercapnia, impaired cerebral blood flow regulation, increased intracranial pressure and development of subsequent neonatal brain injury.
• Suctioning was commonly applied outside of resuscitation guidelines

Systematic Review

Reference not yet available

PICOST

The PICOST (Population, Intervention, Comparator, Outcome, Study Designs, and Time Frame)

Population: newborn infants who are born through non-meconium-stained amniotic fluid in the delivery room

Intervention: initial suctioning of the mouth and nose

Comparison: no initial suctioning

• Outcomes:
  • o Primary Outcome:

Receipt of Assisted Ventilation (important)

• o Secondary Outcomes
  • Advanced resuscitation and stabilization interventions (intubation, chest compressions / epinephrine (adrenaline)) in DR (critical)
• Receipt and duration of oxygen supplementation (important)
• Adverse effects of intervention (e.g., apnoea, bradycardia, injury, infection, low Apgar scores, dysrhythmia) (important)
• Unanticipated admission to the NICU (important)

Study Design: Randomized controlled trials (RCTs) and non-randomized studies (non-RCTs, interrupted time series, controlled before-and-after studies and cohort studies) were eligible for inclusion. Unpublished studies (e.g., conference abstracts, trial protocols), case series and animal studies were excluded.

Timeframe: All years and all languages were included if an English abstract was available. The final literature search was performed on 21^st September 2021.

Definitions used in this systematic review:

Newly born: first hour of life

Non-meconium stained amniotic fluid: clear or slightly yellowish liquid that surrounds the unborn baby (fetus) during pregnancy. It is contained in the amniotic sac. It can sometimes be blood stained during delivery

Suction of the mouth or nose (Oro/nasopharyngeal suction) is a method used to clear secretions from the oropharynx or nasopharynx, or both, through the application of negative pressure via a suction catheter or bulb syringe. {Waltman 2004 32}

Episodes of apnoea cessation of breathing for more than 20 seconds or a shorter pause associated with bradycardia or cyanosis (AAP 2003 914) during initial oro/naso/pharyngeal suctioning or immediately (within 20 seconds) following initial mouth or nose (Oro/nasopharyngeal suctioning) or both

Bradycardia heart rate less than 100 beats per minute for 10 seconds or longer during or immediately (<20 seconds) following suctioning

Cardiac dysrhythmias: any variation of normal cardiac rhythm or rate of heart beat during or immediately (<20 seconds) following suctioning

Assisted Ventilation: receipt of positive pressure ventilatory support including Continuous Positive Airways Pressure (CPAP)

Initial Suctioning: Suctioning of the mouth or nose (Oro/nasopharyngeal suctioning) as an initial action prior to any other airway and breathing manoeuvres (excluding head positioning)

Unexpected admission to NICU: >34 weeks gestation infant admitted to NICU but not as a result of a protocol that is based purely on birthweight or gestation (as opposed to clinical condition)

PROSPERO registration:

CRD42021286258, 22^nd October 2021.

Systematic Review search strategy:

Review of studies was coordinated using Covidence. Papers identified through the structured search strategy were screened for inclusion by two authors based on title and abstract. Selected studies received a full text review by two authors and were either included or excluded with reasons for exclusion. Disagreements were resolved by consensus. Included studies underwent risk of bias, quality, certainty and imprecision assessments.

Bias, inconsistency, indirectness, imprecision and certainty assessments:

Outcomes ratings using the GRADE classifications of critical or important were based on a consensus for international neonatal resuscitation guidelines (range 1-3 low importance for decision-making, 4-6 important but not critical for decision-making, 7-9 critical for decision-making) {Strand 2020 328}.

For each study, two authors independently assessed risk of bias (RoB) using the ROB2 tool for RCTs and the ROBINS-I for observational studies, using a template constructed in Covidence. {Sterne 2016 i4919; Higgins 2011 d5928} RoB was defined at both an overall study level and where studies contributed data to an individual outcome their RoB for that outcome was assessed. All RoB assessments were decided by consensus.

Certainty of evidence (confidence in the estimate of effect) for each outcome was decided by consensus using the GRADE framework including RoB, inconsistency, indirectness, imprecision, and publication bias.

Consensus on Science

COMPARISON: initial suctioning of the mouth and nose vs. no initial suctioning in newborn infants born through non meconium stained amniotic fluid

This systematic review identified 9 randomized controlled trials and 2 observational studies which met inclusion criteria for the review.

The results of 2 RCTs {Gungor 2005 453, Gungor 2006 9}, (one including infants born by caesarean section and the other vaginal births) for oxygen saturation and heart rate levels are almost identical and have much smaller standard deviations than other studies. The task force has sought clarification from the authors about the data. Outcome data with and without these 2 RCTS are presented.

For the important primary outcome of receiving assisted ventilation, 5 RCTS, including 1022 participants found that for suctioning compared to no suctioning, clinical benefit or harm could not be excluded (RR 0.72; 95% CI 0.40, 1.31 p=0.28; absolute risk difference (ARD) 13 fewer per 1000 95% CI, 28 fewer to 15 more per 1000). Inclusion criteria for 4 of the RCTS included no maternal or fetal pathological changes during gestation or delivery, single fetus, term gestation. Evidence was of very low certainty (downgraded for very serious risk of bias, serious inconsistency, very serious indirectness and very serious imprecision) {Bancalari 2019 271, Gungor 2005 453, Gungor 2006 9, Kelleher 2013 326, Modarres Nejad 2014 400}. Post-hoc sensitivity analysis without the Gungor 2005 and Gungor 2006 studies did not change the RR and adjusted the ARD to 18 fewer (95% CI, 39 fewer to 20 more) per 1000.

For the important primary outcome of receiving advanced resuscitation and stabilization interventions (intubation, chest compressions / epinephrine (adrenaline) in DR), 5 RCTS, including 1022 participants found that for suctioning vs. no suctioning, clinical benefit or harm could not be excluded (RR 0.72; 95% CI, 0.40, 1.31 p=0.28; ARD 13 fewer per 1000 95% CI, 28 fewer to 15 more patients per 1000). Inclusion criteria for 4 of the RCTS selected healthy term infants. Evidence was of very low certainty (downgraded for very serious risk of bias, serious inconsistency, very serious indirectness and very serious imprecision) {Bancalari 2019 271, Gungor 2005 453, Gungor 2006 9, Kelleher 2013 326, Modarres Nejad 2014 400}. Analysis without the Gungor 2005 and Gungor 2006 studies did not change the RR and increased the ARD to 18 fewer (95% CI, 39 fewer to 20 more).

For the important secondary outcome of receipt and duration of oxygen supplementation, 4 RCTs included 534 healthy term infants and reported all newborns were born in good clinical condition and did not need supplemental oxygen. Clinical benefit or harm could not be excluded as the event rate was zero in both groups so a relative risk could not be calculated. Evidence was of very low certainty (downgraded for very serious risk of bias, serious inconsistency, very serious indirectness and very serious imprecision) {Bancalari 2019 271, Gungor 2005 453, Gungor 2006 9, Modarres Nejad 2014 400}. Analysis without the Gungor studies did not alter this finding.

For the important secondary outcome of adverse effects of intervention (e.g., apnoea, bradycardia, injury, infection, low Apgar scores, dysrhythmia) the following evidence was identified:

Outcomes related to oxygen saturations:

For the important secondary outcome of of oxygen saturations at 5 minutes 5 RCTs including 560 participants found for suctioning vs. no suctioning possible harm (mean difference (MD] -9.08% (95%CI, -9.51 to -8.66% p<0.001)). Evidence was of very low certainty (downgraded for serious risk of bias, serious inconsistency, very serious indirectness). {Bancalari 2019 271, Gungor 2005 453, Gungor 2006 9, Modarres Nejad 2014 400, Takahashi 2009 261}.

Analysis without the two Gungor studies found for suctioning vs no suctioning, clinical benefit or harm could not be excluded (MD -0.26% (95%CI, -1.77 to 1.26%) p=0.74). The evidence was of very low certainty, (downgraded for serious risk of bias, serious inconsistency and very serious indrectness). {Bancalari 2019 271, Modarres Nejad 2014 400, Takahashi 2009 261}

For the important secondary outcome of of oxygen saturations at 9 minutes 3 RCTs including 280 participants, for suctioning vs no suctioning found possible harm (MD -1.52% 95% CI, -2.69 to -0.35% p=0.01). This finding was statistically significant but of unclear clinical significance. Evidence was of very low certainty (downgraded for serious risk of bias, serious inconsistency, very serious indirectness) {Bancalari 2019 271, Modarres Nejad 2014 400, Takahashi 2009 261}

For the important secondary outcome of of oxygen saturations at 10 minutes 2 RCTs including 110 participants found clinical benefit or harm could not be excluded with no significant difference in saturations in infants receiving suction (MD -0.14 (95%CI, -1.17, 0.89) p=0.78]. Evidence was of very low certainty (downgraded for serious risk of bias, serious inconsistency, very serious indirectness) {Bancalari 2019 271, Takahashi 2009 261}.

For the important secondary outcome of oxygen saturations over the first 10 minutes of life the data were presented in different ways in different studies, precluding a comprehensive meta-analysis of all studies that reported data on this outcome.

For the important secondary outcome of of oxygen saturations over the first 10 minutes from birth 3 RCTs {Bancalari 2019 271, Carrasco 1997 832, Gungor 2006 9} including 254 participants provided evidence of very low certainty (downgraded for serious risk of bias, serious imprecision and very serious indirectness) and 1 prospective observational study {Konstantelos 2015} including 346 participants gave graphical representations of saturations over time from birth. All show a trend to slightly lower oxygen saturations (suctioning vs. no suctioning) although by 10 minutes of age saturations were very similar in infants who did and did not receive suctioning at birth.

One RCT including 20 healthy term participants reported slightly lower saturations in those receiving suctioning at 5 minutes but a trend to slightly higher saturation readings at 10 and 15 minutes. Evidence was of very low certainty (downgraded for very serious risk of bias, very serious indirectness and very serious imprecision). {Waltman 2004, 32}

Time to reach target saturations of 86% or 92%

Some studies Gungor 2005 453, Gungor 2006 9, Modarres Nejad 2014 400} reported the proportion of infants that received suctioning or no suctioning who achieved target saturations at certain time points whilst another {Carrasco 1997 832} reported mean (SD) time to achieve target saturations. The target saturations reported are those selected by studies included in this systematic review.

For the important secondary outcome of time to reach target oxygen saturations of 86% or 92%

Two RCTs {Modarres Nejad 2014 400, Carrasco 1997 832} provided data in a form that could not be meta-analysed. In one RCT including 170 participants all infants with suctioning achieved 92% saturations by 11 minutes vs. 9 minutes in the group receiving no suction. {Modarres Nejad 2014 400} The authors noted that no babies in the suctioned group achieved 92% saturations before 8 minutes. In one RCT including 30 participants, mean (SD) time to achieve saturations of 86% was 8.2 +/-3.3 minutes (suctioning) and 5.0 minutes +/- 1.2 (no suction). For 92% saturations the times (suctioning vs. no suctioning) were 10.2 +/-3.3 minutes and 6.8 +/- 1.8 minutes respectively. {Carrasco 1997 832}

Two RCTs {Gungor 2005 453, Gungor 2006 9} including 280 participants (all healthy, term infants) found 140 infants with no suctioning all achieved oxygen saturations of 86% by 5 minutes and 92% by 6 minutes. In contrast only 2.9% of the 140 infants with suctioning achieved saturations of 86% by 5 minutes and none achieved saturations of 92% by 6 minutes. In the suctioning group the maximum time to achieve saturations of 86% and 92% were 8 and 11 minutes, respectively. Evidence was of very low certainty (downgraded for serious imprecision and very serious indirectness)

One prospective observational study {Konstantelos 2015 777} including 346 participants reported 1 episode of severe desaturation to <75% following suctioning.

One prospective observational study {Pocivalnik 2015 153} enrolled 138 infants born at term by elective caesarean section into a study of cerebral and peripheral muscle tissue oxygenation. They reported 36 infants who received oropharyngeal suctioning and 36 controls and found no significant difference in heart rate, oxygen saturations, cerebral and peripheral muscle tissue oxygenation between infants receiving and not receiving suctioning.

For the important secondary outcome of respiratory rate >60 in the first 24 hours evidence from one RCT with 488 participants (not restricted to healthy infants and including those ≥35 weeks gestation), showed clinical benefit or harm could not be excluded (RR 0.99; 95% CI, 0.82, 1.20 p=0.94); ARD 5 fewer per 1000 with those receiving suctioning vs. no suctioning (95% CI, 83 fewer to 92 more per 1000 patients receiving suctioning). Evidence was of moderate certainty {Kelleher 2013 326}.

For the important outcome of heart rate at 5 minutes, 3 RCTs including 364 participants found clinical benefit or harm could not be excluded (MD 5; 95% CI 3.8,6.2 p<0.001) however both groups had a heart rate in the normal range and no bradycardias were reported in either group. Evidence was of very low certainty (downgraded for serious inconsistency and very serious indirectness) {Bancalari 2019 271, Gungor 2005 453, Gungor 2006 9}. Analysis without the two Gungor studies did not change this finding but altered the MD [MD -1.00 (95%CI, -7.96, 5.96)].

Insufficient data on the important secondary outcome of low Apgar scores (<7) was available for analysis.

For the secondary outcome of Apgar scores (score of 10 at 5 minutes) 3 RCTs including 450 participants showed possible harm (Relative risk [RR], 0.63; 95% CI, 0.57, 0.70 p<0.001) ARD reduction (suctioning vs. no suctioning) 370 fewer (95% CI, 430 fewer to 300 fewer) per 1000 patients receiving suctioning). This finding was statistically significant but of unclear clinical significance. Evidence was of very low certainty (downgraded for serious indirectness) {Gungor 2005 453, Gungor 2006 9, Modarres Nejad 2014 400}.

Analysis without the two Gungor studies showed no significant difference in Apgar scores (score of 10 at 5 minutes) [MD 1.00 (0.98, 1.02) p=1] so in this analysis clinical benefit or harm could not be excluded.

For the important secondary outcome of unanticipated admission to the NICU one RCT included 448 infants of ≥35 weeks’ gestation, clinical benefit or harm cannot be excluded (Relative risk [RR], 1.50; 95% CI, 0.96, 2.30 p=0.07) ARD 91 more per 1000 with no suctioning vs. suctioning (95% CI, 8 fewer to 238 more per 1000 patient receiving no suctioning). Evidence was of very low certainty (downgraded for serious risk of bias and indirectness and very serious imprecision) {Kelleher 2013 326}.

Insufficient data were available to be able to report on the important secondary outcomes of soft tissue injury, infection and bradycardia.

Subgroup Analyses:

A priori subgroup analyses:

• · Gestational age categories (gestational age is used to define categories, birthweight would only be used in studies that did not report gestational age)
  • o ≥34 +0 weeks or >2000g
• o 28 +0 - 33 +6 weeks or 1000-2000g
• o <28 +0 weeks or <1000g
• · Route and method of delivery
  • o Vaginal vs Caesarean section
• · Suction device used (Bulb vs Catheter Suction)

Gestational age: Insufficient data were available for this subgroup analysis as the studies included in this systematic review were predominantly in term babies. Only one prospective observational study {Konstantelos 2015 777} and one RCT {Kelleher 2013 326} included both preterm and term infants.

The Kelleher study included infants ≥35 weeks although the median (IQR) gestation was 39 (38–40) weeks for the no suction (wipe) group and 39 (38–40) for suction group. {Kelleher 2013 326} The majority of the infants in the Konstantelos study were born at term. {Konstantelos 2015 777}

Vaginal vs Caesarean section: insufficient data were available for a subgroup analysis of the following outcomes: receipt of assisted ventilation, advanced resuscitation, receipt of supplemental oxygen, unanticipated NICU admission.

For the outcome of oxygen saturations at 5 minutes there is a difference favoring no suction in both vaginal delivery and caesarean section subgroups with high heterogeneity within subgroups (I² =97%) and evidence of an interaction by delivery type (test for subgroup differences 0.03) also with high heterogeneity between subgroups (I²=78.6%). Given the very high heterogeneity, despite almost identical results in two studies {Gungor 2005 453, Gungor 2006 9}, a sensitivity analysis was carried out. With the two Gungor studies removed from both subgroups there was no difference in saturations in either subgroup with no interaction (p=0.86) and heterogeneity reduced (I²=0%).

Among the two methodologically identical RCTs, {Gungor 2005 453, Gungor 2006 9} one studied vaginally born infants and the other those born by caesarean section, each included 140 participants and found identical time to achieve saturations of 86% or 92%.

Suction device used (bulb vs catheter Suction)

Two RCTs {Kelleher 2013 326, Waltman 2004 32} studied infants receiving bulb suction vs. no suction or wiping. No studies compared bulb suction to catheter suction. Outcomes in the Kelleher and Waltman studies were reported differently, hence comparison could not be made and subgroup analysis was not possible.

Treatment Recommendations

We suggest that suctioning of clear amniotic fluid from the nose and mouth should not be used as a routine step for newborn infants at birth (weak recommendation, very low certainty of evidence). Airway positioning and suctioning should be considered if airway obstruction is suspected (good practice statement).

Justification and Evidence to Decision Framework Highlights

In making this recommendation, the Newborn Life Support Task Force noted that studies that reported oxygen saturations at set time points up to 10 minutes all showed either no difference or lower saturations in babies receiving suctioning vs. no suctioning. The pooled mean difference in oxygen saturations (MD -9.08% (95%CI, -9.51, -8.66) p<0.001) at 5 minutes narrowed over the first 10 minutes of life with little difference from 10 minutes of age onwards. Studies that reported saturations at fixed time points and studies that displayed saturation data as a graph all showed a pattern of lower saturations over the first few minutes of life in infants receiving suctioning. This was supported by studies that looked the time taken to achieve target saturations, these found that infants that received suctioning at birth took longer to achieve those target saturations.

The Task Force concluded that no benefit from routine suctioning of clear amniotic fluid was found. They were hesitant to conclude possible harm from lower saturations in the first 10 minutes of life because the data consisted of graphical trends, although it was noted that this was a consistent trend to lower oxygen saturation in those with suctioning. The statistically significant reduction in oxygen saturations at 5 minutes was not seen in all analyses and the statistically significant reduction in oxygen saturation sat 9 minutes may not be clinically significant.

The Task Force considered that it was not justified to routinely use an intervention such as oral and nasal suctioning in the absence of benefit. Although the participants included in studies included in this systematic review were predominantly healthy term newborn infants, the potential for delay in resuscitation for those who required it was also a concern.

It was also noted that fewer babies receiving suctioning achieved a 5 minute Apgar score of 10 (RR 0.63; 95% CI, 0.57 to 0.70 p<0.001; ARD 370 fewer per 1000 95% CI, 430 fewer to 300 fewer per 1000).

Subgroup analysis suggested an interaction by delivery type (vaginal delivery vs. caesarean section) and found high heterogeneity. The interaction and the heterogeneity were not evident when the Gungor studies were removed, an analysis that was conducted to explore the high heterogeneity.

This systematic review recommendation does not apply to situations where there are concerns regarding airway obstruction.

Knowledge Gaps

The role of suctioning of clear amniotic fluid at birth for infants at higher risk of needing resuscitation or respiratory support

The role of suctioning of clear amniotic fluid at birth for preterm infants

Adherence to resuscitation guidelines in relation to the practice of suctioning clear amniotic fluid

Attachments

NLS 5120 Suctioning Clear Amniotic Fluid at Birth Et D

References

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