Effect of Endotracheal Suctioning on Infants Born through Meconium-Stained Amniotic Fluid: A Meta-analysis

OBJECTIVE

Meconium is a common finding in amniotic fluid and placental specimens, particularly in term and post-term pregnancies. The objective of this paper was to perform a meta-analysis to examine the impact of endotracheal suctioning on the occurrence of meconium aspiration syndrome (MAS), mortality, and complications.

STUDY DESIGN

PubMed, EMBASE, and the Cochrane library were systematically searched for comparative studies. Odds ratios (ORs), weighted mean differences (WMDs), and corresponding 95% confidence intervals (CIs) were used to compare the outcomes.

RESULTS

Twelve studies were included in the meta-analysis. There were no significant impacts of endotracheal suctioning on the occurrence of MAS (OR = 3.05, 95% CI: 0.48-19.56), mortality (OR = 1.25, 95% CI: 0.35-4.44), the need for mechanical ventilation (OR = 4.20, 95% CI: 0.32-54.72), the occurrence of pneumothorax (OR = 0.99, 95% CI: 0.34-2.85), persistent pulmonary hypertension of the newborn (PPHN), (OR = 1.31, 95% CI: 0.58-2.98), hypoxic-ischemic encephalopathy (HIE) (OR = 0.82, 95% CI: 0.52-1.30), and length of stay (WMD = -0.11, 95% CI: -0.99-0.77).

CONCLUSION

Routine endotracheal suctioning at birth is not useful in preventing MAS, mortality, mechanical ventilation, PPHN, HIE, and prolonged length of stay in neonates born through MSAF.

KEY POINTS

· Routine suctioning is not recommended for newborns.. · Endotracheal aspiration is not beneficial for MAS.. · Future research may focus on selected neonates..

Gastric Lavage for Prevention of Feeding Intolerance in Neonates Delivered Through Meconium-Stained Amniotic Fluid: A Systematic Review and Meta-Analysis

BACKGROUND

The role of gastric lavage in neonates delivered through meconium-stained amniotic fluid remains unclear.

OBJECTIVE

This study evaluated the effects of gastric lavage, compared to no gastric lavage, on the incidences of feeding intolerance, respiratory distress, meconium aspiration synd-rome, time to establish breastfeeding, hospitalization and pro-cedure-related complications in late-preterm and term neonates delivered through meconium-stained amniotic fluid.

DESIGN

Systematic review and meta-analysis.

DATA SOURCES AND SELECTION CRITERIA

MEDLINE, EMBASE, CENTRAL, and other databases were searched for randomized controlled trials and quasi-randomized controlled trials using search terms: neonate OR newborn infant, meconium OR meconium-stained amniotic fluid, and lavage OR gastric lavage from inception to May 2020. Data were pooled in RevMan and analyzed in GRADE.

RESULTS

Pooled effects (9 randomized controlled trials, number=3668), showed a significant reduction in the incidence of feeding intolerance (relative risk 0.70; 95% confidence interval 0.58,0.85, I2=0) after gastric lavage. No difference was observed for the incidence of meconium aspiration syndrome (4 studies) or procedure-related complications (7 studies). Only one study, reporting the proportion of neonates with low oxygenation (SpO2<85%), did not find any significant difference. No study evaluated the effects of gastric lavage on respiratory distress, breastfeeding, and hospitalization.

CONCLUSIONS

Low-quality evidence supported the role of gastric lavage for the prevention of feeding intolerance in late-preterm and term neonates born through meconium-stained amniotic fluid. Applicability of results was limited by the high risk of bias. Well-conducted randomized controlled trials with important patient outcomes are needed before recommending the practice of gastric lavage.

Tracheal suction at birth in non-vigorous neonates born through meconium-stained amniotic fluid

BACKGROUND

Neonates born through meconium-stained amniotic fluid (MSAF) are at risk of developing meconium aspiration syndrome (MAS). Neonates who are non-vigorous due to intrapartum asphyxia are at higher risk of developing MAS. Clearance of meconium from the airways below the vocal cords by tracheal suction before initiating other steps of resuscitation may reduce the risk of development of MAS. However, conducting tracheal suction may not only be ineffective, it may also delay effective resuscitation, thus prolonging and worsening the hypoxic-ischaemic insult.  OBJECTIVES: To evaluate the efficacy of tracheal suctioning at birth in preventing meconium aspiration syndrome and other complications among non-vigorous neonates born through meconium-stained amniotic fluid.

SEARCH METHODS

We used the standard search strategy of Cochrane Neonatal to search Cochrane Central Register of Controlled Trials (CENTRAL 2020, Issue 11) in the Cochrane Library; Ovid MEDLINE(R) and Epub Ahead of Print, In-Process & Other Non-Indexed Citations, Daily and Versions(R) (1946 to 25 November 2020) for randomised controlled trials (RCTs) and quasi-randomised trials. We also searched clinical trials databases and the reference lists of retrieved articles for RCTs and quasi-randomised trials (up to November 2020).

SELECTION CRITERIA

We included studies enrolling non-vigorous neonates born through MSAF, if the intervention being tested included tracheal suction at the time of birth with an intent to clear the trachea of meconium before regular breathing efforts began. Tracheal suction could be performed with an endotracheal tube or a wide-gauge suction catheter. Neonates in the control group should have been resuscitated at birth with no effort made to clear the trachea of meconium.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trial quality and extracted data, consulting with a third review author about any disagreements. We used standard Cochrane methodological procedures, including assessment of risk of bias for all studies. Our primary outcomes were: MAS; all-cause neonatal mortality; and incidence of hypoxic-ischaemic encephalopathy (HIE). Secondary outcomes included: need for mechanical ventilation; incidence of pulmonary air leaks; culture-positive sepsis; and persistent pulmonary hypertension. We used the GRADE approach to assess the certainty of evidence.

MAIN RESULTS

We included four studies (enrolling 581 neonates) in the review. All four studies were conducted in tertiary care hospitals in India. Three of the four studies included neonates born at and beyond term gestation, whereas one included neonates born at and beyond 34 weeks of gestation. Due to the nature of the intervention, it was not possible to blind the healthcare personnel conducting the intervention. Tracheal suction compared to no suction in non-vigorous neonates born through MSAF In non-vigorous infants, no differences were noted in the risks of MAS (RR 1.00, 95% CI 0.80 to 1.25; RD 0.00, 95% CI -0.07 to 0.08; 4 studies, 581 neonates) or all-cause neonatal mortality (RR 1.24, 95% CI 0.76 to 2.02; RD 0.02, 95% CI -0.03 to 0.07; 4 studies, 575 neonates) with or without tracheal suctioning. No differences were reported in the risk of any severity HIE (RR 1.05, 95% CI 0.68 to 1.63; 1 study, 175 neonates) or moderate to severe HIE (RR 0.68, 95% CI 0.43 to 1.09; 1 study, 152 neonates) among non-vigorous neonates born through MSAF. We are also uncertain as to the effect of tracheal suction on other outcomes such as incidence of mechanical ventilation (RR 0.99, 95% CI 0.68 to 1.44; RD 0.00, 95% CI -0.06 to 0.06; 4 studies, 581 neonates), pulmonary air leaks (RR 1.22, 95% CI 0.38 to 3.93; RD 0.00, 95% CI -0.02 to 0.03; 3 studies, 449 neonates), persistent pulmonary hypertension (RR 1.29, 95% CI 0.60 to 2.77; RD 0.02, 95% CI -0.03 to 0.06; 3 studies, 406 neonates) and culture-positive sepsis (RR 1.32, 95% CI 0.48 to 3.57; RD 0.01, 95% CI -0.03 to 0.05; 3 studies, 406 neonates). All reported outcomes were judged as providing very low certainty evidence.

AUTHORS' CONCLUSIONS

We are uncertain about the effect of tracheal suction on the incidence of MAS and its complications among non-vigorous neonates born through MSAF. One study awaits classification and could not be included in the review. More research from well-conducted large trials is needed to conclusively answer the review question.

Outcomes of endotracheal suctioning in non-vigorous neonates born through meconium-stained amniotic fluid: a systematic review and meta-analysis

OBJECTIVE

We aimed to systematically review and analyse the outcomes of non-endotracheal suctioning (non-ETS) versus ETS in non-vigorous meconium-stained neonates.

DESIGN

We conducted a systematic review of non-ETS and ETS in non-vigorous infants born through meconium-stained amniotic fluid (MSAF). We searched PubMed/Medline, Scopus, Clinical Trials.gov, Cumulative Index to Nursing and Allied Health, and Cochrane Library databases from inception to November 2019, using keywords and related terms. Only non-vigorous infants born through MSAF included in randomised controlled trials, were included. We calculated overall relative risks (RRs) and mean differences with 95% CIs using a random-effects model, to determine the impact of ETS in non-vigorous infants born through MSAF.

MAIN OUTCOME MEASURES

The primary outcome was the incidence of meconium aspiration syndrome (MAS). Secondary outcomes were respiratory outcome measures (pneumothorax, persistent pulmonary hypertension of the newborn, secondary pneumonia, need for respiratory support, duration of mechanical ventilation), initial resuscitation and others including shock, perinatal asphyxia, convulsions, neonatal mortality, blood culture-positive sepsis and duration of hospital stay.

RESULTS

A total of 2085 articles were identified in the initial database search. Four studies, including 581 non-vigorous meconium-stained infants, fulfilled the inclusion criteria, comprising 292 infants in the non-ETS group and 289 in the ETS group. No statistically significant difference was found for MAS (RR 0.98; 95% CI 0.71 to 1.35).

CONCLUSIONS

Initiating ETS soon after birth in non-vigorous meconium-stained infants may not alter their neonatal outcomes.

Gastric lavage in babies born through meconium stained amniotic fluid in prevention of early feed intolerance: A randomized controlled trial

OBJECTIVE

To evaluate the efficacy of gastric lavage (GL) in preventing feed intolerance in babies born through Meconium stained amniotic fluid (MSAF).

STUDY DESIGN

In this randomized trial conducted at a tertiary care hospital, neonates born of MSAF after 34 weeks period of gestation requiring routine care were randomly allocated to GL with 10 ml/kg of normal saline. The control group did not receive GL. The subjects were monitored for first 24 hours in predefined time epochs. The primary outcome was incidence of feed intolerance which was defined as vomiting or abdominal distension more than 2 cm from baseline measure. Babies were also monitored for potential adverse events due to GL and total duration of hospital stay.

RESULTS

Baseline parameters were comparable. The incidence of feed intolerance was not significant in the GL group [4.6% vs 9.2%; RR 0.92 (0.29-3)]. There were no adverse events secondary to GL. The duration of hospital stay was comparable between groups.

CONCLUSION

GL in neonates born of MSAF does not reduce feed intolerance.

Facilitating normal physiology in the presence of meconium stained liquor

There is sufficient evidence to support the practice of optimal cord clamping in normal labour and birth. In this paper, the physiology of meconium stained liquor (MSL), meconium aspiration syndrome and the practice of optimal cord clamping in babies born through MSL, is discussed. Guidelines suggest not stimulating babies born through MSL, at birth, to avoid aspiration. However, the obvious stimulation resulting from early clamping and cutting the cord, leaves a baby with no choice but to inhale, but this appears to be overlooked in practice. Midwives in their role as supporters of normal physiology are in a position to question this routine intervention in the absence of any evidence to support it.

N-acetylcysteine effectively diminished meconium-induced oxidative stress in adult rabbits

Since inflammation and oxidative stress are fundamental in the pathophysiology of neonatal meconium aspiration syndrome (MAS), various anti-inflammatory drugs have been used in experimental and clinical studies on MAS. This pilot study evaluated therapeutic potential of N-acetylcysteine in modulation of meconium-induced inflammation and oxidative lung injury. Oxygen-ventilated adult rabbits were intratracheally given 4 ml/kg of meconium (25 mg/ml) or saline (Sal, n = 6). Thirty minutes later, meconium-instilled animals were treated with intravenous N-acetylcysteine (10 mg/kg, Mec + NAC, n=6) or were non-treated (Mec, n = 6). All animals were oxygen-ventilated for additional 5 hours. Total and differential blood leukocyte counts were determined at baseline, and at 1, 3 and 5 h of the treatment. After sacrificing animals, left lung was saline-lavaged and total and differential cell counts in the bronchoalveolar lavage fluid were determined. Right lung was used for biochemical analyses and for estimation of wet-dry weight ratio. In lung tissue homogenate, thiobarbituric acid-reactive substances (TBARS), dityrosine, lysine-lipid peroxidation (LPO) products, and total antioxidant status (TAS) were detected. In isolated lung mitochondria, TBARS, dityrosine, lysine-LPO products, thiol group content, conjugated dienes, and activity of cytochrome c oxidase were estimated. To evaluate systemic effects of meconium instillation and NAC treatment, TBARS and TAS were determined also in plasma. To evaluate participation of eosinophils in the meconium-induced inflammation, eosinophil cationic protein (ECP) was detected in plasma and lung homogenate. Meconium instillation increased oxidation markers and ECP in the lung and decreased TAS (all P<0.05). NAC treatment reduced ECP and oxidation markers (all P<0.05, except of dityrosine in homogenate and conjugated dienes in mitochondria) and prevented a decrease in TAS (P<0.01) in lung homogenate compared to Mec group. In plasma, NAC decreased TBARS (P<0.001) and ECP, and increased TAS (both P<0.05) compared to Mec group. Concluding, N-acetylcysteine diminished meconium-induced inflammation and oxidative lung injury.

Gastric lavage for prevention of feeding problems in neonates with meconium-stained amniotic fluid: a randomised controlled trial

BACKGROUND

The role of gastric lavage in preventing retching, vomiting and secondary meconium aspiration syndrome in neonates with meconium-stained amniotic fluid is uncertain, and no there are no definitive guidelines.

OBJECTIVE

To evaluate the effect of gastric lavage in preventing retching, vomiting and secondary meconium aspiration syndrome in neonates with meconium-stained amniotic fluid.

METHODS

This was an open-label, parallel, randomized controlled trial conducted in the labour room, postnatal and neonatal wards of a tertiary-care teaching hospital. Vigorous neonates of ≧34 weeks gestation with meconium-stained amniotic fluid were randomised into two groups using block randomisation. Infants requiring oxygen, in respiratory distress or with major congenital malformations were excluded. Infants in the study group received elective gastric lavage in the labour room after initial stabilisation. No gastric lavage was done in the control group. The newborns were assessed for retching, vomiting and secondary meconium aspiration syndrome in the first 48 hrs of life or until discharge from the hospital, whichever was later.

RESULTS

A total of 267 newborns were randomly assigned to the gastric lavage group and 269 to the no gastric lavage group. There were no statistical differences in overall feeding between the two groups (6·74% vs 10·78%). Feeding of two newborns in the no-lavage group had to be omitted for the initial few hours because of vomiting; this did not happen in any newborn in the lavage group. No newborn in either group developed secondary meconium aspiration syndrome.

CONCLUSION

Gastric lavage in newborns with meconium-stained amniotic fluid does not prevent or reduce the occurrence of feeding problems or secondary meconium aspiration syndrome.

Amnioinfusion for meconium-stained liquor in labour

BACKGROUND

Amnioinfusion is thought to dilute meconium present in the amniotic fluid and so reduce the risk of meconium aspiration.

OBJECTIVES

To assess the effects of amnioinfusion for meconium-stained liquor on perinatal outcome.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (1 December 2013).

SELECTION CRITERIA

Randomised trials comparing amnioinfusion with no amnioinfusion for women in labour with moderate or thick meconium staining of the amniotic fluid.

DATA COLLECTION AND ANALYSIS

Three review authors independently assessed eligibility and trial quality, and extracted data.

MAIN RESULTS

Fourteen studies of variable quality (4435 women) are included.Subgroup analysis was performed for studies from settings with limited facilities to monitor the baby's condition during labour and intervene effectively, and settings with standard peripartum surveillance.Settings with standard peripartum surveillance: there was considerable heterogeneity for several outcomes. There was no significant reduction in the primary outcomes meconium aspiration syndrome, perinatal death or severe morbidity, and maternal death or severe morbidity. There was a reduction in caesarean sections (CSs) for fetal distress but not overall. Meconium below the vocal cords diagnosed by laryngoscopy was reduced, as was neonatal ventilation or neonatal intensive care unit admission, but there was no significant reduction in perinatal deaths or other morbidity. Planned sensitivity analysis excluding trials with greater risk of bias resulted in an absence of benefits for any of the outcomes studied.Settings with limited peripartum surveillance: three studies were included. In the amnioinfusion group there was a reduction in CS for fetal distress and overall; meconium aspiration syndrome (three studies, 1144 women; risk ratio (RR) 0.17, 95% confidence interval (CI) 0.05 to 0.52); perinatal mortality (three studies, 1151 women; RR 0.24, 95% CI 0.11 to 0.53) and neonatal ventilation or neonatal intensive care unit admission. In one of the studies, meconium below the vocal cords was reduced and, in the other, neonatal encephalopathy was reduced.

AUTHORS' CONCLUSIONS

Amnioinfusion is associated with substantive improvements in perinatal outcome only in settings where facilities for perinatal surveillance are limited. It is not clear whether the benefits are due to dilution of meconium or relief of oligohydramnios.In settings with standard peripartum surveillance, some non-substantive outcomes were improved in the initial analysis, but sensitivity analysis excluding trials with greater risk of bias eliminated these differences. Amnioinfusion is either ineffective in this setting, or its effects are masked by other strategies to optimise neonatal outcome.The trials reviewed are too small to address the possibility of rare but serious maternal adverse effects of amnioinfusion.

Delivery room management of meconium-stained infant

This article discusses the historical background, epidemiology, and pathophysiology of meconium-stained amniotic fluid and provides current concepts in delivery room management of meconium-stained neonate including the current Neonatal Resuscitation Program guidelines.

Amnioinfusion for meconium-stained liquor in labour

BACKGROUND

Amnioinfusion is thought to dilute meconium present in the amniotic fluid and so reduce the risk of meconium aspiration.

OBJECTIVES

To assess the effects of amnioinfusion for meconium-stained liquor on perinatal outcome.

SEARCH STRATEGY

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (May 2009).

SELECTION CRITERIA

Randomised trials comparing amnioinfusion with no amnioinfusion for women in labour with moderate or thick meconium-staining of the amniotic fluid.

DATA COLLECTION AND ANALYSIS

Two review authors assessed eligibility and trial quality, and extracted data, independently.

MAIN RESULTS

Thirteen studies of variable quality (4143 women) are included.Subgroup analysis was performed for studies from settings with limited facilities to monitor the baby's condition during labour and intervene effectively, and settings with standard peripartum surveillance.Settings with standard peripartum surveillance: there was considerable heterogeneity for several outcomes. There was no significant reduction in the primary outcomes meconium aspiration syndrome, perinatal death or severe morbidity, and maternal death or severe morbidity. There was a reduction in caesarean sections (CSs) for fetal distress but not overall. Meconium below the vocal cords diagnosed by laryngoscopy was reduced, as was neonatal ventilation or neonatal intensive care unit admission, but there was no significant reduction in perinatal deaths or other morbidity. Planned sensitivity analysis excluding trials with greater risk of bias resulted in an absence of benefits for any of the outcomes studied.Settings with limited peripartum surveillance: two studies (855 women) were included. In the amnioinfusion group there was a reduction in CS for fetal distress and overall; meconium aspiration syndrome (RR 0.25, 95% CI 0.13 to 0.47), and neonatal ventilation or neonatal intensive care unit admission; and a trend towards reduced perinatal mortality (RR 0.37, 95% CI 0.13 to 1.01). In one of the studies, meconium below the vocal cords was reduced and, in the other, neonatal encephalopathy was reduced.

AUTHORS' CONCLUSIONS

Amnioinfusion is associated with substantive improvements in perinatal outcome only in settings where facilities for perinatal surveillance are limited. It is not clear whether the benefits are due to dilution of meconium or relief of oligohydramnios.In settings with standard peripartum surveillance, some non-substantive outcomes were improved in the initial analysis, but sensitivity analysis excluding trials with greater risk of bias eliminated these differences. Amnioinfusion is either ineffective in this setting, or its effects are masked by other strategies to optimise neonatal outcome.The trials reviewed are too small to address the possibility of rare but serious maternal adverse effects of amnioinfusion.

SOGC Clinical Practice Guideline. Management of meconium at birth. No. 224, April 2009

OBJECTIVE

To provide clinician direction that is based on the best evidence available on suctioning at the perineum for infants born with meconium stained amniotic fluid.

EVIDENCE

The Medline database was searched for articles published in English from 2000 to 2008 on the topic of management of meconium at birth.

VALUES

The recommendation was made according to guidelines developed by the Canadian Task Force on Preventive Health Care.

WITHDRAWN: Amnioinfusion for meconium-stained liquor in labour

BACKGROUND

Amnioinfusion aims to prevent or relieve umbilical cord compression during labour by infusing a solution into the uterine cavity. It is also thought to dilute meconium when present in the amniotic fluid and so reduce the risk of meconium aspiration. However, it may be that the mechanism of effect is that it corrects oligohydramnios (reduced amniotic fluid), for which thick meconium staining is a marker.

OBJECTIVES

The objective of this review was to assess the effects of amnioinfusion for meconium-stained liquor on perinatal outcome.

SEARCH STRATEGY

The Cochrane Pregnancy and Childbirth Group trials register (October 2001) and the Cochrane Controlled Trials Register (Issue 3, 2001) were searched.

SELECTION CRITERIA

Randomised trials comparing amnioinfusion with no amnioinfusion for women in labour with moderate or thick meconium-staining of the amniotic fluid.

DATA COLLECTION AND ANALYSIS

Eligibility and trial quality were assessed by one reviewer.

MAIN RESULTS

Twelve studies, most involving small numbers of participants, were included. Under standard perinatal surveillance, amnioinfusion was associated with a reduction in the following: heavy meconium staining of the liquor (relative risk 0.03, 95% confidence interval 0.01 to 0.15); variable fetal heart rate deceleration (relative risk 0.65, 95% confidence interval 0.49 to 0.88); and reduced caesarean section overall (relative risk 0.82, 95% confidence interval 0.69 to 1.97). No perinatal deaths were reported. Under limited perinatal surveillance, amnioinfusion was associated with a reduction in the following: meconium aspiration syndrome (relative risk 0.24, 95% confidence interval 0.12 to 0.48); neonatal hypoxic ischaemic encephalopathy (relative risk 0.07, 95% confidence interval 0.01 to 0.56) and neonatal ventilation or intensive care unit admission (relative risk 0.56, 95% confidence interval 0.39 to 0.79); there was a trend towards reduced perinatal mortality (relative risk 0.34, 95% confidence interval 0.11 to 1.06).

AUTHORS' CONCLUSIONS

Amnioinfusion is associated with improvements in perinatal outcome, particularly in settings where facilities for perinatal surveillance are limited. The trials reviewed are too small to address the possibility of rare but serious maternal adverse effects of amnioinfusion.

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.

Combination of budesonide and aminophylline diminished acute lung injury in animal model of meconium aspiration syndrome

Combination of low-dose budesonide and low-dose aminophylline may improve lung function in reduced adverse effects compared with high-dose monotherapy. Adult rabbits intratracheally received 4 ml/kg of saline or meconium (25 mg/ml). Meconium-injured rabbits were treated at 0.5 and 2.5 h after meconium instillation by intravenous aminophylline (1.0 mg/kg), by intratracheal budesonide (0.125 mg/kg) followed by intravenous aminophylline (1.0 mg/kg), or were untreated. Although aminophylline improved some respiratory parameters, budesonide+aminophylline more effectively reduced intrapulmonary shunts and improved gas exchange, without significant cardiovascular effects. Combined treatment reduced lung edema and number of lung neutrophils to a higher extent than aminophylline alone. Both treatments reduced lung peroxidation and in vitro airway reactivity to histamine, with a better effect after aminophylline alone. Combination of budesonide and aminophylline enhanced respiratory parameters more effectively, having fewer side effects than aminophylline alone. However, no additive effect of budesonide was observed on lung peroxidation and in vitro airway reactivity.

[Intrapartum amnioinfusion in patients with meconium-stained amniotic fluid]

OBJECTIVES

The aim of the study was to evaluate the effect of intrapartum amnioinfusion in the presence of meconium stained amniotic fluid.

MATERIAL AND METHODS

93 women with meconium-stained amniotic fluid were assigned to receive amnioinfusion or no amnioinfusion (128 women). The trials were evaluated for fetal distress syndrome, route of delivery, fetal acidemia, Apgar score at 1 and 5 min., meconium aspiration syndrome, postpartum endometritis and maternal hospital stays.

RESULT

Amnioinfusion in cases of meconium-stained fluid did not improve the number of fetal distress symptoms during fetal heart rate monitoring. Amnioinfusion was associated with a significant decrease of neonatal acidemia although it did not improve Apgar score. In our study amnioinfusion was not associated with reduction in the incidence of neonatal outcome and puerperial complications.

[Perinatal risk at term and post-term revisited]

The aim of this review was to revisit the evaluation of risk of foetal and neonatal mortality at term. We analyse the meaning of term period and difficulty to determine the normal duration of the pregnancy. Specific complications associated with post term and the statistic approach of the perinatal risk are analysed, together with various mortality rates and especially the prospective risk introducing foetal term as a new concept. We study various aspect and evolution of non specific morbidity of the term period. An optimal decision for term management should involve pregnant women and the analysed parameters should be taken into consideration.

Aminophylline treatment in meconium-induced acute lung injury in a rabbit model

Administration of methylxanthines may diminish meconium-induced acute lung injury. Meconium-instilled rabbits intravenously received aminophylline (2.0 mg/kg) at two doses 0.5 h and 2.5 h after meconium instillation or were left without treatment, and were oxygen-ventilated for additional 5 h. At the end of experiment, lungs and trachea were excised. Within 5 h after the first dose of treatment, aminophylline significantly improved gas exchange and decreased right-to-left pulmonary shunts, central venous pressure, and ventilatory pressures. Moreover, aminophylline reduced meconium-induced lung edema formation, airway hyperreactivity to histamine, count of neutrophils in bronchoalveolar lavage fluid associated with higher total white blood cells and neutrophils in the blood, and diminished oxidative modifications of proteins and lipids in lung tissue compared with the non-treated meconium-instilled group. In a rabbit model of the meconium aspiration syndrome, aminophylline treatment enhanced pulmonary functions and alleviated oxidative injury and changes in airway reactivity related to lung inflammation.

ACOG Committee Opinion No. 379: Management of Delivery of a Newborn With Meconium-Stained Aminiotic Fluid

In accordance with the new guidelines from the American Academy of Pediatrics and the American Heart Association, all infants with meconium-stained amniotic fluid should no longer routinely receive intrapartum suctioning. If meconium is present and the newborn is depressed, the clinician should intubate the trachea and suction meconium and other aspirated material from beneath the glottis.

Intrapartum amnioinfusion for meconium-stained amniotic fluid: a systematic review of randomised controlled trials

BACKGROUND

Amnioinfusion (AI) is thought to dilute meconium when present in the amniotic fluid and so reduces the risk of meconium aspiration.

OBJECTIVES

To evaluate if AI reduces meconium aspiration syndrome (MAS) and other indicators of morbidity in babies born to women with meconium-stained amniotic fluid (MSAF).

SEARCH STRATEGY

PubMed, Medline, EMBASE, and the Cochrane Controlled Trials Register from January 1980 to May 30, 2005, using the keywords 'amnioinfusion' and 'meconium'.

SELECTION CRITERIA

Randomised trials comparing AI with no AI for women in labour with MSAF. Trial quality was evaluated using pre-established criteria.

DATA COLLECTION AND ANALYSIS

The following morbidity indicators were assessed: MAS, 5-minute Apgar score < 7, arterial cord pH < 7.2, and caesarean section. Studies were stratified according to the level of peripartum surveillance (standard versus limited). Typical relative risks (RRs) with their 95% confidence intervals were calculated for each outcome using a random effects model.

MAIN RESULTS

In clinical settings with standard peripartum surveillance, we found no evidence that AI reduced the risk of MAS (RR 0.59, 95% CI 0.28-1.25), 5-minute Apgar score < 7 (RR 0.90, 95% CI 0.58-1.41), or caesarean delivery (RR 0.89, 95% CI 0.73-1.10). In clinical settings with limited peripartum surveillance, AI appeared to reduce the risk of MAS (RR 0.25, 95% CI 0.13-0.47).

CONCLUSION

In clinical settings with standard peripartum surveillance, the evidence does not support the use of AI for MSAF. In settings with limited peripartum surveillance, where complications of MSAF are common, AI appears to reduce the risk of MAS. However, this finding requires confirmation by further studies.

Evidence-based practices for the fetal to newborn transition

Many common care practices during labor, birth, and the immediate postpartum period impact the fetal to neonatal transition, including medication used during labor, suctioning protocols, strategies to prevent heat loss, umbilical cord clamping, and use of 100% oxygen for resuscitation. Many of the care practices used to assess and manage a newborn immediately after birth have not proven efficacious. No definitive outcomes have been obtained from studies on maternal analgesia effects on the newborn. Although immediate cord clamping is common practice, recent evidence from large randomized, controlled trials suggests that delayed cord clamping may protect the infant against anemia. Skin-to-skin care of the newborn after birth is recommended as the mainstay of newborn thermoregulation and care. Routine suctioning of infants at birth was not been found to be beneficial. Neither amnioinfusion, suctioning of meconium-stained babies after the birth of the head, nor intubation and suctioning of vigorous infants prevents meconium aspiration syndrome. The use of 100% oxygen at birth to resuscitate a newborn causes increased oxidative stress and does not appear to offer benefits over room air. This review of evidence on newborn care practices reveals that more often than not, less intervention is better. The recommendations support a gentle, physiologic birth and family-centered care of the newborn.

Intrapartum transcervical amnioinfusion for meconium-stained amniotic fluid

OBJECTIVE

To assess the rates of cesarean deliveries and perinatal outcome following intrapartum transcervical amnioinfusion in women with meconium-stained amniotic fluid (MSAF) in a setting with no electronic fetal monitoring or specialized neonatal care.

MATERIALS AND METHODS

In this prospective comparative study with 150 women who were in labor and had MSAF, 50 of the women received a transcervical amnioinfusion and the remaining 100 women received standard care. The inclusion criteria were a pregnancy of at least 37 weeks' duration, a single live fetus in cephalic presentation, no major medical or obstetric complications, and no known fetal malformation. The amnioinfusion was performed with 1000 mL of normal saline solution through a red rubber catheter.

RESULTS

Amnioinfusion was associated with a significant decrease in the incidence of low Apgar score (<7) at 1 min (12% vs. 47%; relative risk [RR], 0.26; 95% confidence interval [CI], 0.12-0.56); low Apgar score at 5 min (4% vs. 23%; RR, 0.17; 95% CI, 0.04-0.71); and meconium aspiration syndrome (4% vs. 18%; RR, 0.22; 95% CI, 0.05-0.92). There was also a trend towards a lesser incidence of cesarean deliveries (18% vs. 30%; RR, 0.6; 95% CI, 0.31-1.16) and perinatal deaths (4% vs. 13%; RR, 0.31; 95% CI, 0.07-1.31). The incidence of maternal hospital stays longer than 3 days was significantly lower in the amnioinfusion than in the control group (24% vs. 48%; RR, 0.5; 95% CI, 0.29-0.85). There were no major complications related to amnioinfusion.

CONCLUSIONS

Intrapartum amnioinfusion for MSAF is a simple, safe, effective, and inexpensive procedure feasible in settings where intrapartum monitoring is limited. It is associated with improved perinatal outcome and could lower cesarean delivery rates in low-resource countries.

ACOG Committee Obstetric Practice. ACOG Committee Opinion Number 346, October 2006: amnioninfusion does not prevent meconium aspiration syndrome

Amnioinfusion has been advocated as a technique to reduce the incidence of meconium aspiration and to improve neonatal outcome. However, a large proportion of women with meconium-stained amniotic fluid have infants who have taken in meconium within the trachea or bronchioles before meconium passage has been noted and before amnioinfusion can be performed by the obstetrician; meconium passage may predate labor. Based on current literature, routine prophylactic amnioinfusion for the dilution of amnioinfusion for meconium-stained amniotic fluid should be done only in the setting of additional clinical trials. However, amnioinfusion remains a reasonable approach in the treatment of repetitive variable decelerations, regardless of amniotic fluid meconium status.

[Significance of infusion of sodium bicarbonate in amniotic cavity under continuous internal fetal heart rate monitoring for management of fetal distress during labor]

OBJECTIVE

To investigate the effect of infusion of sodium bicarbonate in amniotic cavity and exchange of amniotic fluid for fetus with distress and acidosis.

METHODS

The patients included 40 cases of oligohydramnios with mild and serious abnormality of fetal heart rate and amniotic fluid contamination of degree II or more during the labor. The 40 cases had exchange of amniotic fluid with infusion under continuous monitoring. Twenty of them had infusion with 5% sodium bicarbonate into amniotic cavity; the other 20 cases received 5% sodium bicarbonate intravenous in fusion. After the labor all the patients had test of arterial blood gas in umbilical cord and the fetuses were evaluated with Apgar score.

RESULTS

(1) the effective rate was 88% in the group of infusion into amniotic cavity and 85% in the group of exchange of amniotic fluid. (2) The arterial blood pH, PO(2), HCO(3)(-), ABE, SBE in the group of amniotic cavity infusion with 5% sodium bicarbonate were all higher than group of IV infusion, however PCO(2) was significantly lower than the group of IV (P < 0.05).

CONCLUSION

Infusion into amniotic cavity and exchange of amniotic fluid is effective therapy for fetal distress due to oligohydramnios and can prevent meconium aspiration syndrome; infusion of antacids medicine (5% sodium bicarbonate) into amniotic cavity is effective and safe therapy for fetus with acidosis.

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.

Amnioinfusion for the prevention of the meconium aspiration syndrome

BACKGROUND

It is uncertain whether amnioinfusion (infusion of saline into the amniotic cavity) in women who have thick meconium staining of the amniotic fluid reduces the risk of perinatal death, moderate or severe meconium aspiration syndrome, or both.

METHODS

We performed a multicenter trial in which 1998 pregnant women in labor at 36 or more weeks of gestation who had thick meconium staining of the amniotic fluid were stratified according to the presence or absence of variable decelerations in fetal heart rate and then randomly assigned to amnioinfusion or to standard care. The composite primary outcome measure was perinatal death, moderate or severe meconium aspiration syndrome, or both.

RESULTS

Perinatal death, moderate or severe meconium aspiration syndrome, or both occurred in 44 infants (4.5 percent) of women in the amnioinfusion group and 35 infants (3.5 percent) of women in the control group (relative risk, 1.26; 95 percent confidence interval, 0.82 to 1.95). Five perinatal deaths occurred in the amnioinfusion group and five in the control group. The rate of cesarean delivery was 31.8 percent in the amnioinfusion group and 29.0 percent in the control group (relative risk, 1.10; 95 percent confidence interval, 0.96 to 1.25).

CONCLUSIONS

For women in labor who have thick meconium staining of the amniotic fluid, amnioinfusion did not reduce the risk of moderate or severe meconium aspiration syndrome, perinatal death, or other major maternal or neonatal disorders.

In utero Meconium SuctioningMay Prevent Meconium As piration

OBJECTIVE

To assess usefulness of in utero meconium suctioning using endoscopic approach.

MATERIALS AND METHODS

In utero meconium suctioning under direct endoscopic visualization was successfully performed in 11 fetuses in whom thick meconium was detected upon rupture of the membranes. A gas-sterilized flexible fiberoptic scope with an operational channel was introduced via cervix, and meconium was aspirated from the fetal mouth. Definitive suction was performed in all neonates immediately after birth.

RESULTS

Endoscopic meconium suctioning was successfully performed in 11 out of 16 fetuses with retrieval of 3-12 ml of meconium. Only 1 neonate in this series of cases had meconium below the vocal cords and none developed meconium aspiration syndrome postnatally.

CONCLUSION

Because fatal meconium aspiration syndrome is largely an intrauterine event, the concept of in utero prophylactic meconium suctioning may serve as an effective modality for its prevention.

Oropharyngeal and nasopharyngeal suctioning of meconium-stained neonates before delivery of their shoulders: multicentre, randomised controlled trial

BACKGROUND

Meconium aspiration syndrome (MAS) is a life-threatening respiratory disorder in infants born through meconium-stained amniotic fluid (MSAF). Although anecdotal data concerning the efficacy of intrapartum oropharyngeal and nasopharyngeal suctioning of MSAF are conflicting, the procedure is widely used. We aimed to assess the effectiveness of intrapartum suctioning for the prevention of MAS.

METHODS

We designed a randomised controlled trial in 11 hospitals in Argentina and one in the USA. 2514 patients with MSAF of any consistency, gestational age at least 37 weeks, and cephalic presentation were randomly assigned to suctioning of the oropharynx and nasopharynx (including the hypopharynx) before delivery of the shoulders (n=1263), or no suctioning before delivery (n=1251). Postnatal delivery-room management followed Neonatal Resuscitation Program guidelines. The primary outcome was incidence of MAS. Clinicians diagnosing the syndrome and designating other study outcomes were masked to group assignment. An informed consent waiver was used. Analysis was by intention to treat.

FINDINGS

18 infants in the suction group and 15 in the no suction group did not meet entry criteria after random assignment. 87 in the suction group were not suctioned, and 26 in the no suction group were suctioned. No significant difference between treatment groups was seen in the incidence of MAS (52 [4%] suction vs 47 [4%] no suction; relative risk 0.9, 95% CI 0.6-1.3), need for mechanical ventilation for MAS (24 [2%] vs 18 [1%]; 0.8, 0.4-1.4), mortality (9 [1%] vs 4 [0.3%]; 0.4, 0.1-1.5), or in the duration of ventilation, oxygen treatment, and hospital care.

INTERPRETATION

Routine intrapartum oropharyngeal and nasopharyngeal suctioning of term-gestation infants born through MSAF does not prevent MAS. Consideration should be given to revision of present recommendations.

Amnioinfusion in thick meconium

OBJECTIVE

There are conflicting reports regarding the results of amnioinfusion in the management of meconium passage in utero. This study was done to evaluate transcervical amnioinfusion for meconium stained amniotic fluid during labour.

METHODS

196 women at term in early labour with meconium were randomized to receive either transcervical intrapartum amnioinfusion with saline (96) or routine obstetrical care (100). Transcervical amnioinfusion of one liter saline infused over 30-45 minutes. End points were relief of decelerations, incidence of vaginal delivery, presence of meconium below the neonatal cords, and X-ray evidence of meconium aspiration.

RESULTS

Amnioinfusion resulted in relief of decelerations in 75% of cases as compared to 7% in the control group. Eighty-eight percent of patients delivered vaginally as compared to 58% in the control group (p< 0.001). Neonatal outcome was significantly better in the infusion group. The incidence of meconium below the vocal cords was reduced from 48% to 17% (p< 0.004) using amnioinfusion with positive X-rays for meconium aspiration in only 12.5% versus 26% (p < 0.5).

CONCLUSIONS

We concluded that transcervical intrapartum amnioinfusion is a safe, simple and inexpensive technique that reduces operative intervention and improves neonatal outcome, and is of tremendous relevance in developing countries.

Effect of amnioinfusion for meconium stained amniotic fluid on perinatal outcome

OBJECTIVE

To see the effect of amnioinfusion on perinatal outcome in cases of meconium staining of liquor.

METHODS

This study was conducted in department of Obstetrics and Gynaecology, unit 1, Jinnah Postgraduate Medical Centre, Karachi, from 1st January 1998 to 31st December 2000. Four hundred patients were included in this study, assigning 200 for amnioinfusion and 200 as control. All patients were matched in both the groups with respect to age, antenatal booking, parity, gestational age, stage of labour, colour of amniotic fluid and fetal birth weight. Both the groups were found to be comparable.

RESULTS

The rate of Caesarean section was found to be 37% in amnioinfusion group, which collaborates with other international studies. The fetal outcome was better i.e. 91% alive and healthy, after amnioinfusion due to dilution of meconium stained amniotic fluid with physiological solutions. The perinatal outcome was recorded by Apgar score at 5 minutes. The perinatal morbidity and mortality both were significantly lowered and was found to be 6% as compared to 14% in control, which was also noticed by less number of admissions in nursery i.e. 12% and perinatal deaths. The incidence of meconium aspiration syndrome was found to be 56% in control and was reduced to 22% after amnioinfusion in the other arm of the study.

CONCLUSION

These results are very encouraging and suggestion can be safely made that in future amnioinfusion will be the ideal method of preventing fetal distress due to meconium stained amniotic fluid.

[Meconium-stained amniotic fluid and intra-amniotic infection]

OBJECTIVE

To explore the relationship between meconium-stained amniotic fluid and Fifty-six women of cesarean section with intact membrane and intra-amniotic infection.

METHODS

without parturient were divided into 3 groups according to the property of amniotic fluid (no meconium, I to approximately II degree meconium stainedness, and III degree mecomium stainedness). The content of interleukin-6 in amniotic fluid was measured with ELISA. The infiltration of inflammatory cells in the placenta and its membrane was determined by the pathological diagnosis. The neonatal Apgar score and puerperial infection after the surgery were analyzed.

RESULTS

There were no significant differences in the content of IL-6 in amniotic fluid and in the infiltration of inflammatory cells among the 3 groups. But the rate of neonatal asphyxia in the meconium-stained cases was significantly higher than that without meconium.

CONCLUSION

Meconium-stained amniotic fluid is a marker of fetal distress, but it is not related to intra-amniotic infection.

Simultaneous use of intrapartum fetal pulse oximetry and amnioinfusion in meconium stained amniotic fluid

OBJECTIVE

Fetal pulse oximetry is a minimally invasive, simple technique which continuously helps to reflect in utero well-being. The presence of meconium in the amniotic fluid may be a clinical sign of fetal hypoxaemia. Amnioinfusion has a beneficial effect on the incidence of meconium aspiration syndrome (MAS), and the presence of meconium below the level of the vocal cords.

STUDY DESIGN

We studied the impact of amnioinfusion combined with fetal pulse oximetry on the incidence of meconium aspiration syndrome and operative delivery.

RESULTS

The retrospective analysis revealed that the presence of meconium below the level of vocal cords was significantly reduced. The frequency of cesarean section is decreased, however, it did not reach statistical significance.

CONCLUSION

Fetal pulse oximetry may be used in combination with amnioinfusion and cardiotocography (CTG) to reduce the risk of meconium aspiration syndrome and the number of instrumental deliveries and improve perinatal outcome.

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.

Changing obstetric practices associated with decreasing incidence of meconium aspiration syndrome

OBJECTIVE

To describe changes in neonatal and obstetric practices that may have contributed to the decreasing incidence of meconium aspiration syndrome in our population during this time.

METHODS

We compared neonatal and obstetric characteristics of 61 infants diagnosed with meconium aspiration syndrome with 1365 infants born through moderate or thick meconium-stained amniotic fluid at more than 37 weeks' completed gestation. Data were prospectively collected, and all respiratory diagnoses were concurrently made. Three distinct birth year groups were analyzed based on changing obstetric practice paradigms.

RESULTS

Meconium aspiration syndrome decreased nearly four-fold from 1990-1992 to 1997-1998 (5.8% to 1.5% of meconium-stained infants more than 37 weeks; P <.003). The only change in neonatal characteristics was a 33% decrease in births more than 41 weeks with a reciprocal 33% increase in births 38-39 weeks during 1997-1998. Significant changes in obstetric practice included more frequent diagnosis of nonreassuring fetal heart rate patterns, greater use of amnioinfusion, and increased cesarean delivery rate in 1997-1998. By logistic regression analysis, the only consistent risk factor for meconium aspiration syndrome across all three epochs was the presence of tracheal meconium.

CONCLUSION

Reduction in post-term delivery was the most important factor in reducing meconium aspiration syndrome.

Amnioinfusion for meconium-stained liquor in labour

BACKGROUND

Amnioinfusion aims to prevent or relieve umbilical cord compression during labour by infusing a solution into the uterine cavity. It is also thought to dilute meconium when present in the amniotic fluid and so reduce the risk of meconium aspiration. However, it may be that the mechanism of effect is that it corrects oligohydramnios (reduced amniotic fluid), for which thick meconium staining is a marker.

OBJECTIVES

The objective of this review was to assess the effects of amnioinfusion for meconium-stained liquor on perinatal outcome.

SEARCH STRATEGY

The Cochrane Pregnancy and Childbirth Group trials register (October 2001) and the Cochrane Controlled Trials Register (Issue 3, 2001) were searched.

SELECTION CRITERIA

Randomised trials comparing amnioinfusion with no amnioinfusion for women in labour with moderate or thick meconium-staining of the amniotic fluid.

DATA COLLECTION AND ANALYSIS

Eligibility and trial quality were assessed by one reviewer.

MAIN RESULTS

Twelve studies, most involving small numbers of participants, were included. Under standard perinatal surveillance, amnioinfusion was associated with a reduction in the following: heavy meconium staining of the liquor (relative risk 0.03, 95% confidence interval 0.01 to 0.15); variable fetal heart rate deceleration (relative risk 0.65, 95% confidence interval 0.49 to 0.88); and reduced caesarean section overall (relative risk 0.82, 95% confidence interval 0.69 to 1.97). No perinatal deaths were reported. Under limited perinatal surveillance, amnioinfusion was associated with a reduction in the following: meconium aspiration syndrome (relative risk 0.24, 95% confidence interval 0.12 to 0.48); neonatal hypoxic ischaemic encephalopathy (relative risk 0.07, 95% confidence interval 0.01 to 0.56) and neonatal ventilation or intensive care unit admission (relative risk 0.56, 95% confidence interval 0.39 to 0.79); there was a trend towards reduced perinatal mortality (relative risk 0.34, 95% confidence interval 0.11 to 1.06).

REVIEWER'S CONCLUSIONS

Amnioinfusion is associated with improvements in perinatal outcome, particularly in settings where facilities for perinatal surveillance are limited. The trials reviewed are too small to address the possibility of rare but serious maternal adverse effects of amnioinfusion.

Randomised trial of amnioinfusion during labour with meconium stained amniotic fluid

OBJECTIVE

To assess the effect of amnioinfusion during labour with meconium stained amniotic fluid on caesarean section rate and perinatal outcome.

DESIGN

Prospective randomised controlled study.

SETTING

A tertiary care teaching hospital in India.

POPULATION

Women in labour at term with meconium stained amniotic fluid.

METHODS

Two hundred women in labour with > or = 37 weeks gestation, single cephalic presentation with moderate or thick meconium were randomised to control and amnioinfusion groups at a 1:1 ratio. Amnioinfusion was performed using 500 mL of normal saline over a period of 30 minutes in a study group. The control group received routine care. Both groups had intermittent auscultation of fetal heart rate during labour.

MAIN OUTCOME MEASURES

The primary outcome measure was caesarean section rate. Secondary outcome measures were meconium aspiration syndrome, 1 minute and 5 minute apgar < 7, hypoxic ischaemic encephalopathy, neonatal intensive care unit admission, meconium at the level of vocal cords.

RESULTS

The caesarean section rate in the amnioinfusion group was less than the control group (RR 0.47; 95% CI 0.24-0.93). Amnioinfusion was associated with a significant decrease in the incidence of meconium at the vocal cords (P = 0.001); improvement in 1 minute apgar scores (P < 0.05), respiratory distress (P = 0.002) and fewer admissions to nursery compared with the controls. This sample size was inadequate to study the impact on meconium aspiration syndrome.

CONCLUSION

Amnioinfusion in an under resourced labour ward decreases caesarean section rates and fetal morbidity.