The need for delivery room intubation of thin meconium in the low-risk newborn: a clinical trial

[The evolution of approach in the resuscitation of neonates born with meconium-stained amniotic fluid: a tale of two countries, China and U.S.A., in the past 60 years]

Neonates born through meconium-stained amniotic fluid (MSAF) may develop complications including meconium aspiration syndrome, persistent pulmonary hypertension of newborn and death. The approach to the resuscitation of these neonates has significantly evolved for the past few decades. Initially, under direct visualization technique, neonates with MSAF were commonly suctioned below the vocal cords soon after delivery. Since 2015, Neonatal Resuscitation Program (NRP^®) of the American Academy of Pediatrics has recommended against "routine" endotracheal suctioning of non-vigorous neonates with MSAF but favored immediate resuscitation with positive pressure ventilation via face-mask bagging. However, the China neonatal resuscitation 2021 guidelines continue to recommend routine endotracheal suctioning of non-vigorous neonates born with MSAF at birth. This review article discusses the differences and the rationales in the approach in the resuscitation of neonates with MSAF between Chinese and American NRP^® guidelines over the past 60 years.

[S3 guidelines on "full-term vaginal birth" from an anesthesiological perspective : Worthwhile knowledge for anesthesiologists]

The publication of the new S3 guidelines on "full-term vaginal birth" and the guidelines on cesarean section, also published in 2020, provide further steps towards the promotion of evidence-based medicine in obstetrics, even if the exact configuration of neonatal monitoring during birth, in particular, is still the subject of current discussions. The multiprofessionality in the medical supervision of a birth is also fundamentally well-represented in the compilation of the S3 guidelines by the participating actors and specialist societies. Important from an anesthesiological perspective is the fact that neuraxial procedures still represent the gold standard in obstetric analgesia. With remifentanil PCA an alternative option is available that enables a reliable analgesia to be accomplished, e.g. when there are contraindications to performing neuraxial methods, if this is appropriate under the prevailing circumstances (1:1 support and appropriate monitoring). During an uncomplicated birth the strict fasting rules are relaxed. Overall, the guidelines underline the importance of self-determination and self-control for the expectant mother and give the highest priority to the safety and well-being of mother and child; however, this presupposes that the expectant mother is sufficiently informed about the value of neuraxial analgesia. For this it appears to be of importance to initiate information proposals, which go beyond the usual information sessions for parents that are often organized exclusively by midwives.

Delivery room management of the newborn

Neonatal resuscitation is an attempt to facilitate the dynamic transition from fetal to neonatal physiology. This article outlines the current practices in delivery room management of the neonate. Developments in cardiopulmonary resuscitation techniques for term and preterm infants and advances in the areas of cerebral resuscitation and thermoregulation are reviewed. Resuscitation in special circumstances (such as the presence of congenital anomalies) are also covered. The importance of communication with other members of the health care team and the family is discussed. Finally, future trends in neonatal resuscitation are explored.

The pros and cons of suctioning at the perineum (intrapartum) and post-delivery with and without meconium

Routine oronasopharyngeal suctioning (ONPS) of the infant at delivery is a common practice in the delivery room. ONPS is performed to remove lung fluid, meconium, or other secretions from the airway, thereby improving oxygenation and/or preventing aspiration. However, there are controversies regarding this practice, as it seems to be associated with complications. In the presence of clear amniotic fluid, routine ONPS in infants born vaginally and by cesarean section is associated with bradycardia, apnea, and delays in achieving normal oxygen saturations, with no benefit. Intrapartum ONPS and post-natal endotracheal suctioning of vigorous infants born through meconium-stained amniotic fluid (MSAF) does not prevent meconium aspiration syndrome (MAS). Although depressed infants born through MSAF are at risk of developing MAS, there is no evidence that endotracheal suctioning of these infants reduces MAS.

Newborn resuscitation in resource-limited settings

Every year, an estimated 4 million newborn infants die worldwide in the first 4 weeks of life. A large majority of these deaths occurs during the first day of life. One of the United Nations' eight Millennium Development Goals is to decrease child mortality; prevention of neonatal deaths by appropriate resuscitation will have a significant impact on achieving this goal. Newborn resuscitation needs to be carried out in all the settings where asphyxiated babies are born, including: community or domiciliary settings for home births; rural health centers/midwifery stations, where attendants with basic resuscitation skills might be available; district-level facilities where staff are available but skills vary; and urban referral and tertiary care centers. Individuals at all levels require training and seldomly used skills need to be maintained so that, when required, resuscitation can be carried out efficiently and effectively. Simple resuscitation techniques include: positioning, drying, and keeping the baby warm; assessing the heart rate, color, and respirations; recognizing the need for, and administering, assisted ventilation with a bag and mask or tube and mask. These maneuvers can be carried out with simple equipment and appropriate training. Research in developing countries remains sparse, with 90% of research being done in more developed parts of the world, which experience just 10% of the problems. The significant gaps in our understanding include: failing to agree on a definition of the term 'asphyxia', lack of knowledge of the impact of community approaches on the prevention and management of asphyxia, and a failure to recognize the best method to determine heart rate.

Obstetric approaches to the prevention of meconium aspiration syndrome

Meconium aspiration syndrome (MAS) is associated with increased risk for perinatal mortality and morbidities. To provide an overview of the advances in our knowledge concerning the obstetric approaches to the prevention of MAS. The evidence of the effectiveness of intrapartum surveillance, amnioinfusion, and delivery room management in the prevention of MAS are reviewed in the present paper. Meconium aspiration syndrome remains one of the most common but challenging conditions for obstetricians and pediatricians. The available evidence did not demonstrate a beneficial effect of either of obstetric strategies in the prevention of MAS.

Outcomes of patients who participate in randomized controlled trials compared to similar patients receiving similar interventions who do not participate

BACKGROUND

Some people believe that patients who take part in randomised controlled trials (RCTs) face risks that they would not face if they opted for non-trial treatment. Others think that trial participation is beneficial and the best way to ensure access to the most up-to-date physicians and treatments. This is an updated version of the original Cochrane review published in Issue 1, 2005.

OBJECTIVES

To assess the effects of patient participation in RCTs ('trial effects') independent both of the effects of the clinical treatments being compared ('treatment effects') and any differences between patients who participated in RCTs and those who did not. We aimed to compare similar patients receiving similar treatment inside and outside of RCTs.

SEARCH STRATEGY

In March 2007, we searched The Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, The Cochrane Methodology Register, SciSearch and PsycINFO for potentially relevant studies. Our search yielded 7586 new references. In addition, we reviewed the reference lists of relevant articles.

SELECTION CRITERIA

Randomized studies and cohort studies with data on clinical outcomes of RCT participants and similar patients who received similar treatment outside of RCTs.

DATA COLLECTION AND ANALYSIS

At least two review authors independently assessed studies for inclusion, assessed study quality and extracted data.

MAIN RESULTS

We identified 30 new non-randomized cohort studies (45 comparisons): no new RCTs were found. This update now includes five RCTs (yielding 6 comparisons) and 80 non-randomized cohort studies (130 comparisons), with 86,640 patients treated in RCTs and 57,205 patients treated outside RCTs. In the randomised studies, patients were invited to participate in an RCT or not; these comparisons provided limited information because of small sample sizes (a total of 412 patients) and the nature of the questions they addressed. When the results of RCTs and non-randomized cohorts that reported dichotomous outcomes were combined, there were 98 comparisons; there was also heterogeneity (P < 0.00001, I(2) = 42.2%) between studies. No statistical significant differences were found for 85 of the 98 comparisons. Eight comparisons reported statistically significant better outcomes for patients treated within RCTs, and five comparisons reported statistically significant worse outcomes for patients treated within RCTs. There was significant heterogeneity (P < 0.00001, I(2) = 58.2%) among the 38 continuous outcome comparisons. No statistically significant differences were found for 30 of the 38 comparisons. Three comparisons reported statistically significant better outcomes for patients treated within RCTs, and five comparisons reported statistically significant worse outcomes for patients treated within RCTs.

AUTHORS' CONCLUSIONS

This review indicates that participation in RCTs is associated with similar outcomes to receiving the same treatment outside RCTs. These results challenge the assertion that the results of RCTs are not applicable to usual practice.

Outcomes of patients who participate in randomised controlled trials compared to similar patients receiving similar interventions who do not participate

BACKGROUND

Some people believe that patients who take part in randomised controlled trials (RCTs) face risks that they would not face if they opted for non-trial treatment. Others think that trial participation is beneficial and the best way to ensure access to the most up to date physicians and treatments.

OBJECTIVES

To assess the effects of patient participation in RCTs ('trial effects') independent both of the effects of the clinical treatments being compared ('treatment effects') and any differences between patients who participated in RCTs and those who did not.

SEARCH STRATEGY

In May 2001, we searched The Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, The Cochrane Methodology Register, SciSearch and PsycINFO for potentially relevant studies. Our search yielded over 10,000 references. In addition, we reviewed the reference lists of relevant articles and wrote to over 250 investigators to try to obtain further information.

SELECTION CRITERIA

Randomised studies and cohort studies with data on clinical outcomes of RCT participants and similar patients who received similar treatment outside of RCTs.

DATA COLLECTION AND ANALYSIS

At least two reviewers independently assessed studies for inclusion, assessed study quality and extracted data. Study authors were contacted for additional information.

MAIN RESULTS

We included five randomised studies (yielding 6 comparisons) and 50 non-randomised cohort studies (85 comparisons), with 31,140 patients treated in RCTs and 20,380 patients treated outside RCTs. In the randomised studies, patients were invited to participate in an RCT or not; these comparisons provided limited information because of small sample sizes (a total of 412 patients) and the nature of the questions they addressed. There was statistically significant heterogeneity (P < 0.002, I(2) = 36.2%) among the 73 dichotomous outcome comparisons; none of the potential explanatory factors we investigated helped to explain this heterogeneity. No statistically significant differences were found for 63 of the 73 comparisons. Eight comparisons reported statistically significant better outcomes for patients treated within RCTs, and two comparisons reported statistically significant worse outcomes for patients treated within RCTs. There were no statistically significant differences in heterogeneity (P = 0.53, I(2) = 0%) or in outcomes (SMD 0.01, 95% CI -0.10 to 0.12) of patients treated within and outside RCTs in the 18 comparisons which had used continuous outcomes.

AUTHORS' CONCLUSIONS

This review indicates that participation in RCTs is not associated with greater risks than receiving the same treatment outside RCTs. These results challenge the assertion that the results of RCTs are not applicable to usual practice.

New Australian Neonatal Resuscitation Guidelines

New Australian Neonatal Resuscitation Guidelines highlight the recent advances in neonatal resuscitation. Resuscitation should start with air and only use oxygen if the infant does not respond. CPAP and PEEP should be considered for premature infants with meconium stained liquor. Sucking out the mouth and nose is not necessary. Infants less than 28 weeks gestation should be placed in a polyethylene bag or wrap to keep warm. Chest compressions, when required, remain at 3:1 inflation. The endotracheal tube position must be verified with a carbon dioxide detector.

Newborn resuscitation: defining best practice for low-income settings

Current resuscitation practices are often poor in low-income settings. The purpose of this review was to summarise recent evidence, relevant to developing countries, on best practice in the provision of newborn resuscitation. Potential studies for inclusion were identified using structured searches of MEDLINE via PubMed. Two reviewers independently evaluated retrieved studies for inclusion. The methodological quality of the selected articles was assessed using the Oxford Centre for Evidence-Based Medicine (CEBM) levels of evidence, whilst the Scottish Intercollegiate Guidelines Network (SIGN) grading system was used for subsequent recommendations. Based on available evidence, where there is meconium-stained liquor, routine perineal suction of all babies and endotracheal suction of active babies do not prevent meconium aspiration syndrome and have potential risks. Adequate ventilation is possible with a bag-valve-mask device and room air is just as efficient as oxygen for initial resuscitation. This review supports the view that effective resuscitation is possible with basic equipment and minimal skills. Thus, where resources are limited, it should be possible to improve neonatal outcomes through promotion of the effective use of a bag-valve-mask alone, without access to more sophisticated and expensive technologies. Basic, effective resuscitation should therefore be available at all health facilities and potentially in the community.

Intrapartum and postdelivery management of infants born to mothers with meconium-stained amniotic fluid: evidence-based recommendations

The article reviews and critically evaluates the available evidence to determine whether the current recommendations for the management of infants born through meconium stained amniotic fluid (MSAF) should be maintained. Authors provide evidence-based recommendations regarding the benefits of amnioinfusion prior to delivery, oral suctioning of the newborn prior to delivery of the shoulder, and the practice of routine endotracheal suctioning of the newborn born through MSAF in preventing meconium aspiration syndrome (MAS). Authors also discuss the gaps in knowledge in all the above interventions to prevent MAS.

Have the year 2000 neonatal resuscitation program guidelines changed the delivery room management or outcome of meconium-stained infants?

OBJECTIVE

To study the impact of neonatal resuscitation program (NRP) guidelines on delivery room (DR) management of infants born through meconium-stained amniotic fluid (MSAF).

STUDY DESIGN

A retrospective study of all term (>or=37 weeks) infants born through MSAF was performed. Patients were divided into two periods: pre year 2000 NRP and post year 2000 NRP. Meconium consistency, APGAR scores and intubation (INT) for suctioning and respiratory outcome were recorded. Groups were analyzed using chi (2) tests and stepwise logistic regression.

RESULTS

The incidence of MSAF remained constant in period 1 (13.6%) and period 2 (13.1%) while the proportion of infants intubated fell from 67 to 41% (p<0.001). The incidence of meconium aspiration and nonspecific respiratory distress did not differ between groups.

CONCLUSIONS

Since the implementation of year 2000 NRP guidelines, the rate of DR INT for tracheal suctioning has fallen significantly without a change in overall respiratory complications. Results of this study support the efficacy of year 2000 NRP recommendations.

Systematic review to determine whether participation in a trial influences outcome

OBJECTIVE

To systematically compare the outcomes of participants in randomised controlled trials (RCTs) with those in comparable non-participants who received the same or similar treatment.

DATA SOURCES

Bibliographic databases, reference lists from eligible articles, medical journals, and study authors.

REVIEW METHODS

RCTs and cohort studies that evaluated the clinical outcomes of participants in RCTs and comparable non-participants who received the same or similar treatment.

RESULTS

Five RCTs (six comparisons) and 50 cohort studies (85 comparisons) provided data on 31,140 patients treated in RCTs and 20,380 comparable patients treated outside RCTs. In the five RCTs, in which patients were given the option of participating or not, the comparisons provided limited information because of small sample sizes (a total of 412 patients) and the nature of the questions considered. 73 dichotomous outcomes were compared, of which 59 reported no statistically significant differences. For patients treated within RCTs, 10 comparisons reported significantly better outcomes and four reported significantly worse outcomes. Significantly heterogeneity was found (I2 = 89%) among the comparisons of 73 dichotomous outcomes; none of our a priori explanatory factors helped explain this heterogeneity. The 18 comparisons of continuous outcomes showed no significant differences in heterogeneity (I2 = 0%). The overall pooled estimate for continuous outcomes of the effect of participating in an RCT was not significant (standardised mean difference 0.01, 95% confidence interval -0.10 to 0.12).

CONCLUSION

No strong evidence was found of a harmful or beneficial effect of participating in RCTs compared with receiving the same or similar treatment outside such trials.

Incidence of meconium aspiration syndrome in term meconium-stained babies managed at birth with selective tracheal intubation

The delivery room management of infants born through meconium stained amniotic fluid (MSAF) remains controversial. The aim of this prospective study was to evaluate maternal and neonatal characteristics of MSAF infants and the incidence of meconium aspiration syndrome (MAS) in routine delivery room management which reserved selective intubation for depressed/asphyxiated babies. Between October 1993 and September 1997, a consecutive sample of 3745 full-term infants was analyzed. Of these, 361 were MSAF infants. No significant difference in maternal age, parity, gestational age, sex, low 1 and 5 minute Apgar scores, metabolic acidemia, or need for endotracheal intubation was found between MSAF and non-MSAF infants. Only one of the MSAF infants (0.28%), who needed intubation, developed MAS. Identification of postterm pregnancy and prenatal asphyxia is the best prevention of MAS.

[Meconium in the amniotic fluid: prevention of meconium aspiration and elective tracheal suction]

For many years early systematic intubation and tracheal suction have been advocated for meconium-stained infants. Recent data show that they do not reduce the frequency of pulmonary meconium aspiration and underline the importance of a preventive attitude (i.e., intrapartum oropharyngeal suction before shoulder clearing and thoracic compression before first breathing) together with a selective tracheal suction only in the newborns with obvious oropharyngeal meconial staining.

Endotracheal intubation at birth for preventing morbidity and mortality in vigorous, meconium-stained infants born at term

BACKGROUND

On the basis of evidence from non-randomised studies, it has been recommended that all babies born through thick meconium should have their tracheas intubated so that suctioning of their airways can be performed. The aim is to reduce the incidence and severity of meconium aspiration syndrome. However, for term babies who are vigorous at birth endotracheal intubation may be both difficult and unnecessary.

OBJECTIVES

To determine if endotracheal intubation and suction of the airways at birth in vigorous term meconium-stained babies is more beneficial than routine resuscitation including aspiration of the oro-pharynx.

SEARCH STRATEGY

The search was made from Oxford Database of Perinatal Trials, the Neonatal Trials Registry of the Cochrane Neonatal Collaborative Review Group and information obtained from knowledgeable practising neonatologists.

SELECTION CRITERIA

Randomised trials which compared a policy of routine vs no (or selective) use of endotracheal intubation and aspiration in the immediate management of vigorous term meconium-stained babies at birth.

DATA COLLECTION AND ANALYSIS

Data regarding clinical outcomes including mortality, meconium aspiration syndrome, other respiratory conditions, pneumothorax, need for oxygen supplementation, stridor, convulsions and hypoxic-ischaemic encephalopathy were abstracted and analysed using Revman 3.1.1.

MAIN RESULTS

Four randomised controlled trials of endotracheal intubation at birth in vigorous term meconium-stained babies were identified. Meta-analysis of these trials does not support routine use of endotracheal intubation at birth in vigorous meconium-stained babies to reduce mortality, meconium aspiration syndrome, other respiratory symptoms or disorders, pneumothorax, oxygen need, stridor, HIE and convulsions.

REVIEWER'S CONCLUSIONS

Routine endotracheal intubation at birth in vigorous term meconium-stained babies has not been shown to be superior to routine resuscitation including oro-pharyngeal suction. This procedure cannot be recommended for vigorous infants until more research is available.