WORKSHEET for Evidence-Based Review of Science for Neonatal Resuscitation Worksheet author(s) Date Submitted for review: Revised December 2009

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1 C2010 Worksheet:NRP-012A 31-Jan-2010.doc Page 1 of 16 WORKSHEET for Evidence-Based Review of Science for Neonatal Resuscitation Worksheet author(s) Date Submitted for review: Revised December 2009 Clinical question. "In depressed neonates born through meconium stained amniotic fluid (P), does endotracheal suctioning (I) versus no suctioning (C) improve outcome (O)?" Is this question addressing an intervention/therapy, prognosis or diagnosis? Intervention/ therapy State if this is a proposed new topic or revision of existing worksheet: Revision Conflict of interest specific to this question Do any of the authors listed above have conflict of interest disclosures relevant to this worksheet? No Search strategy (including electronic databases searched). PUBMED: 1. Tracheal suctioning OR Suction (MESH) AND Meconium stained amniotic OR Meconium (MESH). Got 89 hits. 2. Tracheal suctioning OR Suction (MESH) AND Meconium OR Meconium (MESH). Got 160 hits. 3. Tracheal suctioning OR Suction (MESH) AND Meconium aspiration syndrome OR Meconium aspiration syndrome (MESH). Got 133 hits. 4. Endotracheal intubation OR Intubation, tracheal (MESH) AND Meconium stained amniotic OR Meconium (MESH). Got 67 hits. 5. Endotracheal intubation OR Intubation, tracheal (MESH) AND Meconium OR Meconium (MESH). Got 112 hits. 6. Endotracheal intubation OR Intubation, tracheal (MESH) AND Meconium aspiration syndrome AND Meconium aspiration syndrome (MESH). Got 112 hits. COCHRANE: All the searches below were done under MESH Search Suction explode all trees- 648 Intubation, intratracheal explode all trees Meconium explode all trees- 57 Meconium aspiration syndrome explode all trees- 60 Suction explode all trees OR Intubation, intratracheal explode all trees AND Meconium explode all trees OR Meconium Aspiration Syndrome explode all trees. Got 1 Cochrane Review, 10 Clinical trials. EMBASE Intubation, intratracheal/exp/mj OR Intubation, intratracheal AND ( meconium/ exp/mj OR meconium OR meconium aspiration syndrome/exp/mj OR meconium aspiration syndrome ). Got 28 hits. ECC ENDNOTE: Endotracheal suctioning, Meconium aspiration, Depressed infant. Got 600 hits State inclusion and exclusion criteria All English articles were included, for non-english articles only those with abstracts and translated in English were reviewed. Studies that were excluded are those where intubation was for purposes other than suctioning (31), Suctioning on in vigorous infants (6), case reports (15), letters and comments (62), reviews (40).

2 C2010 Worksheet:NRP-012A 31-Jan-2010.doc Page 2 of 16 Number of articles/sources meeting criteria for further review: A total of 21 studies were reviewed.

3 C2010 Worksheet:NRP-012A 31-Jan-2010.doc Page 3 of 16 Summary of evidence Evidence Supporting Clinical Question Good Fair Gregory, 1974 C Falciglia, 1988 C Wiswell, 1990 C Manganaro, 2001 E1 Wiswell, 2000 E1 Dargaville 2006 E1 Ting, 1975 C, E1 Wiswell, 1992 C, E3 Chishty, 1996 C, E1 Hageman, 1988 C Poor Fox, 1977 C, E Level of evidence A = Return of spontaneous circulation C = Survival to hospital discharge E = Other endpoint B = Survival of event D = Intact neurological survival Italics = Animal studies E1- Meconium aspiration syndrome, E2- Need for Mechanical ventilation, E3- Need for ECMO, Evidence Neutral to Clinical question Good Fair Wiswell, 1990 E1 Gregory, 1974 E1 Falciglia, 1988 E1 Yoder, 1994 E1 Peng, 1996 E1 Al Takroni, 1998 C, E1 Bhutta, 1992 E1 Hageman, 1988 E1 Poor Rossi, 1989 E1 Gupta, 1996 E1 Davis, 1985 C, E1 Carson, 1976 E1 Dooley, 1985 C Level of evidence A = Return of spontaneous circulation C = Survival to hospital discharge E = Other endpoint B = Survival of event D = Intact neurological survival Italics = Animal studies E1- Meconium aspiration syndrome, E2- Need for Mechanical ventilation, E3- Need for ECMO, Evidence Opposing Clinical Question

4 C2010 Worksheet:NRP-012A 31-Jan-2010.doc Page 4 of 16 Good Fair Usta, 1995 E1 Poor Level of evidence A = Return of spontaneous circulation C = Survival to hospital discharge E = Other endpoint B = Survival of event D = Intact neurological survival Italics = Animal studies E1- Meconium aspiration syndrome, E2- Need for Mechanical ventilation, E3- Need for ECMO,

5 C2010 Worksheet:NRP-012A 31-Jan-2010.doc Page 5 of 16 REVIEWER S FINAL COMMENTS AND ASSESSMENT OF BENEFIT / RISK: Background Meconium staining of the amniotic fluid (MSAF) occurs in 7-22% of live births (Davis 1985, Dooley 1985, Falciglia 1988, Wiswell 1992). If the MSAF is aspirated by the fetus before or during birth, meconium can obstruct the airways, cause inflammation, interfere with surfactant function and cause respiratory difficulties resulting in meconium aspiration syndrome (MAS). Meconium is found below the cords in 10-40% infants born through MSAF (Dooley 1985, Falciglia 1988, Rossi 1989, Peng 1996). MAS occurs in 2-9% of all cases of MSAF (Rossi 1989, Falciglia 1988, Wiswell 2000). This syndrome carries a mortality rate up to 40% (Davis 1985). Meconium aspiration can occur in utero or immediately after delivery when the infant takes the first breaths. Finding of meconium below the cords or in the trachea has been associated with development of MAS (Gregory 1974, Hageman 1988, Wiswell 2000), therefore suggesting that if meconium can be suctioned out of the trachea there will be reduction in incidence of MAS. Some studies have supported this as they reported that intubation and tracheal suctioning is associated with reduction in MAS and/ or mortality (Gregory 1974, Ting 1975, Fox 1977, Wiswell 1992, Chishty 1996, Manganaro 2001). This resulted in it being used in combination with oro-nasopharyngeal suctioning in all infants born to mothers with MSAF (Carson 1976, Davis 1985, Dooley 1985, Falciglia 1988). A number of these studies did not show reduction in incidence of MAS and/ or mortality (Davis 1985, Dooley 1985, Falciglia 1988). Subsequent to a number of studies that showed it has no benefit in those who are vigorous it has been recommended to be selectively used only in depressed infants (Yoder 1994, Gupta 1996, Peng 1996, Al Takroni 1998, Manganaro 2001). The reason for its selective use in depressed infants is because of increased incidence of MAS in these infants (Rossi 1989, Bhutta 1992, Usta 1995, Peng 1996, Wiswell 2000, Dargaville 2006). Some studies have suggested that aspiration of meconium occurs in-utero and that the damage in the lungs might be related to hypoxia and that it has already taken place by the time the baby is born. Therefore suctioning of depressed infants might have no effect on incidence of MAS. Evidence/ Reviewers comments: A number of studies have reported on incidence of MAS and mortality in infants who were intubated for tracheal suctioning. Some studies have supported tracheal suctioning in infants born through MSAF (Chishty 1996, Fox 1977, Gregory 1974, Tinge 1975, Wiswell 1990, Wiswell 1992) while some have continued to report cases of MAS and mortality in infants born through MSAF despite tracheal suctioning (Davis 1985, Dooley 1985, Falciglia 1988). Most of these studies did not differentiate the effect of tracheal suctioning between those who were depressed and those who were not therefore did not address the question we are trying to answer in this worksheet. Therefore all these studies were grouped as LOE 5. The studies that reported its use in depressed infants were either retrospective or prospective nonrandomized clinical studies and were put under LOE 4. Most of them reported that MAS continued to occur with its associated mortality in depressed infants despite tracheal suctioning (Yoder 1994, Gupta 1996, Peng 1996, Al Takroni 1998). These studies did not make comparison between tracheal suctioning and no tracheal suctioning among depressed infants. So far there have been no published randomized clinical studies that compared intubation with tracheal suctioning to no tracheal suctioning in depressed neonates. Conclusion DISCLAIMER: Potential possible wording for a Consensus on Science Statement. Final wording will differ due to other input and discussion. CONSENSUS ON SCIENCE: Tracheal intubation and suction has been proposed as one of interventions that can reduce MAS and mortality in infants born through MSAF (LOE 5, Gregory 1974, p848; Ting 1975, p767; Fox 1977, p325; Wiswell 1992, p203). Depressed infants born to mothers with MSAF are at increased risk to develop MAS (LOE 4, Peng 1996, p296; Usta 1995, p230; Rossi 1989, p1106; Wiswell 2000, p1, Dargaville 2006, p1712), making selective use of tracheal suctioning for these infants appropriate. Despite use of tracheal

6 C2010 Worksheet:NRP-012A 31-Jan-2010.doc Page 6 of 16 suction in depressed infants, MAS and associated deaths continue to occur in this group of infants (LOE 4- Al Takroni, 1998, p259; Peng, 1996, p296; Gupta, 1996, p293; Yoder, 1994, p77; Bhutta, 1992, p13). There are no studies that have compared intubation and tracheal suctioning and no tracheal suctioning in depressed infants. TREATMENT RECOMMENDATION: Acknowledgements: Citation List 1. Selective tracheal suctioning to prevent meconium aspiration syndrome. Al Takroni AM, Parvathi CK, Mendis KB, Hassan S, Reddy I, Kudair HA. Int J Gynaecol Obstet 1998; 63: ABSTRACT: OBJECTIVE: To analyze the incidence and outcome of meconium aspiration syndrome (MAS) at Al-Yamamah Hospital, Riyadh, Saudi Arabia, where meconium-stained babies have intrapartum obstetrical cleansing of the upper airways, following which depressed/asphyxiated babies are intubated and vigorous babies are observed for 24 h. METHOD: The total live births, records of meconium-stained neonates who had intubations and of those observed, during a 6-year period were reviewed. RESULTS: During this period, there were live births. One in 325 births (0.27%) was complicated by MAS and the mortality rate was 7%. These figures concur with the reported incidence and mortality of MAS following routine combined obstetric-pediatric suction of airways at birth. Of the 265 cases of MAS that occurred during this period, 237 were in the intubated group and 28 in the observed group. The babies of the former group had severe disease compared with that of the latter. All mortality was from the intubated group. CONCLUSION: Adequate obstetrical cleansing of the upper airway in vigorous babies may obviate the need for endotracheal intubation; intubation of depressed babies following this treatment may be useful. Comments: There was a high incidence of MAS in intubated infants in this study. Meconium aspiration syndrome was more severe in depressed infants despite tracheal intubation. There was no comparison between endotracheal suctioned and non-suctioned group among the depressed infants. It is not stated on whether meconium was retrieved below the cords or not during suctioning. Fair, Neutral, LOE 4 2. Meconium aspiration syndrome: the role of resuscitation and tracheal suction in prevention. Bhutta ZA, Jalil S Asia Oceania J Obstet Gynaecol 1992; 18:13-7 ABSTRACT: We reviewed our experience of meconium staining of liquor and meconium aspiration syndrome over a 33 month period. The clinical and radiological severity of disease was assessed in comparison with tracheal suction and resuscitation. Sixty (27%) of newborns with meconium stained liquor subsequently developed MAS. No association was found between the thickness of meconium or its presence on tracheal aspiration with subsequent severity of respiratory disease. However, the

7 C2010 Worksheet:NRP-012A 31-Jan-2010.doc Page 7 of 16 presence of meconium in the trachea was strongly associated with radiological abnormality. The severity of meconium aspiration syndrome and mortality were also related to the clinical stability of the infants at presentation. Our results indicate that intrauterine aspiration and pulmonary maladaptation may play a significant role in meconium aspiration syndrome rather than resuscitative events at delivery. Comments: MAS more severe in depressed infants despite tracheal intubation, no comparison between endotracheal suctioned and non-suctioned group in depressed in infants. Presence of meconium in the trachea was not associated with severity of lung disease. This is different from other studies where they related presence of meconium below the cords to infants being sick. This is one of the studies that suggest MAS as an intra-uterine event. Fair, Neutral, LOE Combined obstetric and pediatric approach to prevent meconium aspiration syndrome Carson BS, Losey RW, Bowes WA Jr, Simmons MA Am J Obstet Gynecol 1976; 126:712-5 ABSTRACT: Routine intrapartum pharyngeal suctioning with a DeLee catheter of infants with meconium staining has significantly reduced the incidence and severity of meconium aspiration syndrome (MAS). There have been no adverse sequelae to this procedure, which is carried out while the infant's head is on the perineum, prior to the onset of respirations. Routine suctioning of the trachea under direct vision after delivery is rarely necessary but should be done if meconium is visualized at the vocal cords. Tracheobronchial lavage with saline may add to the respiratory morbidity. No deaths or severe cases of MAS have occurred since institution of the obstetric suctioning procedure. Comments: MAS occurred despite endotracheal suctioning, included all infants, therefore not all were depressed. It is not stated how many of the infants with MSAF had tracheal suctioning, therefore making it difficult to relate MAS and mortality reported in this study to tracheal suctioning.. Poor, Neutral, LOE Meconium aspiration in neonates: combined obstetric and paediatric intervention improves outcome Chishty AL, Alvi Y, Iftikhar M, Bhutta TI J Pak Med Assoc 1996; 46:104-8 ABSTRACT: All meconium aspiration syndrome cases admitted in the two neonatal units were compared to evaluate the antenatal and natal events including resuscitative measures and outcome of neonates and to confirm the beneficial effects of immediate combined obstetric and paediatric intervention on morbidity and mortality. Neonates managed in nursery at Mayo Hospital (Group 1, n = 44) were delivered at other hospitals and birth centres, underwent resuscitation by obstetricians and/or anaesthetists and then referred. Neonates admitted in the neonatal unit of Lady Willingdon Hospital (Group 2, n = 48) were inborn and resuscitated by paediatric residents. Both groups were comparable for weight, sex, booked status, maturity, history of prolonged labour, fetal distress and Apgar score at 5 minutes. Significant differences were proportion of C-section (62% in Gp 2 v 34% in Gp1), laryngoscopy and tracheal intubation (100% in Gp 2 v 9% in Gp1), time of arrival in the nursery (mean 0.14 hr in Gp 2 v 3.91 hr in Gp 1), persistent cyanosis (43% in Gp 2 v 68% in Gp1), earlier start of feeding (mean 2.4 days in Gp 2 v 3.2 days in group 1) and shorter stay in hospital (2.87 days in Gp 2 v 5 days in Gp 1). 27% cases died in group 2 compared to 47% in group 1 (pvalue = 0.04). Combined immediate obstetric intervention (C-section) and paediatric intervention

8 C2010 Worksheet:NRP-012A 31-Jan-2010.doc Page 8 of 16 (laryngoscopy, tracheal intubation, suction, immediate transfer to nursery) led to reduced severity of meconium aspiration syndrome and lower mortality. Comments: Less mortality in the suctioned group. Included all infants, not all were depressed in the group that was suctioned. Patients came from different hospitals with different rates of tracheal intubation. Though the overall mortality rate was reduced with tracheal suctioning, patients who had low rates of tracheal suctioning had high mortality, but most of these patients were born outside the main center therefore some of the deaths could be due to the fact that they were outborns. Fair, Supportive, LOE The epidemiology of meconium aspiration syndrome: incidence, risk factors, therapies, and outcome. Dargaville PA, Copnell B; Australian and New Zealand Neonatal Network. Pediatrics 2006;117: ABSTRACT: OBJECTIVE: We sought to examine, in a large cohort of infants within a definable population of live births, the incidence, risk factors, treatments, complications, and outcomes of meconium aspiration syndrome (MAS). DESIGN: Data were gathered on all of the infants in Australia and New Zealand who were intubated and mechanically ventilated with a primary diagnosis of MAS (MASINT) between 1995 and 2002, inclusive. Information on all of the live births during the same time period was obtained from perinatal data registries. RESULTS: MASINT occurred in 1061 of 2,490,862 live births (0.43 of 1000), with a decrease in incidence from 1995 to A higher risk of MASINT was noted at advanced gestation, with 34% of cases born beyond 40 weeks, compared with 16% of infants without MAS. Fetal distress requiring obstetric intervention was noted in 51% of cases, and 42% were delivered by cesarean section. There was a striking association between low 5-minute Apgar score and MASINT. In addition, risk of MASINT was higher where maternal ethnicity was Pacific Islander or indigenous Australian and was also increased after planned home birth. Uptake of exogenous surfactant, high-frequency ventilation, and inhaled nitric oxide increased considerably during the study period, with >50% of infants receiving > or =1 of these therapies by Risk of air leak was 9.6% overall, with an apparent reduction to 5.3% in The duration of intubation remained constant throughout the study period (median: 3 days), whereas duration of oxygen therapy and length of hospital stay increased. Death related to MAS occurred in 24 infants (2.5% of the MASINT cohort; 0.96 per 100,000 live births). CONCLUSIONS: The incidence of MASINT in the developed world is low and seems to be decreasing. Risk of MASINT is significantly greater in the presence of fetal distress and low Apgar score, as well as Pacific Islander and indigenous Australian ethnicity. The increased use of innovative respiratory supports has not altered the duration of mechanical ventilation. Comment: It is a population-based rather than hospital based study. This study focused on infants with severe MAS (intubated and ventilated) and found that depressed infants were more likely to have severe disease. There was no comparison on effect of suctioning. Fair, supportive, LOE4 6. Fatal meconium aspiration syndrome occurring despite airway management considered appropriate Davis RO, Harris BA Jr, Wilson ER, Huddleston JF Am J Obstet Gynecol 1985; 15:731-6

9 C2010 Worksheet:NRP-012A 31-Jan-2010.doc Page 9 of 16 ABSTRACT: A combined obstetric-pediatric approach to tracheal toilet is said to prevent serious cases of the potentially fatal meconium aspiration syndrome. After delivery of the head a DeLee trap is used to suction the oropharynx and nasopharynx. Immediately following delivery, endotracheal suction is performed in an effort to remove any remaining meconium-stained amniotic fluid. Although routinely using this approach, we continue to have occasional cases of fatal meconium aspiration syndrome. Therefore, we reviewed the outcome of infants born through meconium-stained fluid. During a 5-year period, 1420 (15%) of 9299 live-born infants had meconium-stained fluid. Thirty (2.1%) of these 1420 developed meconium aspiration syndrome and 12 (40%) died; eight received a postmortem examination. Four had unequivocal evidence of meconium aspiration, two had large numbers of intra-alveolar squamous cells, and two had no evidence of aspiration. We conclude that aggressive airway management during and immediately after delivery does not always prevent fatal meconium aspiration syndrome. Comments: Lung pathology on postmortem showed evidence of MAS despite suctioning. Some of the patients had no evidence of meconium aspiration on post-mortem though they were clinically diagnosed as MAS. This brings into question whether clinical presentation of respiratory distress among infants born through MSAF is due to MAS. Not all were depressed infants. No comparisons. Not all deaths had post-mortem. Poor, Neutral, LOE Meconium below the vocal cords at delivery: correlation with intrapartum events Dooley SL, Pesavento DJ, Depp R, Socol ML, Tamura RK, Wiringa KS Am J Obstet Gynecol 1985;153: ABSTRACT: Intrapartum events were studied in 272 patients with meconium-stained amniotic fluid. All infants underwent DeLee suction followed by intubation and 58 of 272 had meconium present below the vocal cords at delivery. Neither the total duration of variable fetal heart rate decelerations or a continuous saltatory pattern nor the presence or absence of late decelerations could be related to an increased risk of meconium below the vocal cords. When a rising baseline fetal heart rate and decreased variability were present as well, a significantly greater proportion of patients had meconium below the vocal cords. Routine obstetric and pediatric suctioning did not prevent the single death that occurred in a fetus who had deep meconium aspiration in utero. Comments: Retrospective review, endotracheal suction did not prevent MAS. Not all infants were depressed. There were no differences in ph and base deficit between those who had meconium below the cords and those who did not. This suggest that meconium aspiration is occurring before delivery- not linked to events around time of delivery. Apgar scores were not documented for one to assess if the normal ph in infants with meconium below the cords was backed up by normal Apgar scores. Poor, Neutral, LOE Failure to prevent meconium aspiration syndrome Falciglia HS, 1988 Obstet Gynecol 1988;71: ABSTRACT: To determine the impact of routine naso-oropharyngeal DeLee and tracheal suction on the prevention of meconium aspiration syndrome, we compared 755 infants with meconium-stained fluid, born during a 12-month period (1983), with a similar group of 742 infants born in a previous year (1975) when these suctioning techniques were not routinely used. Morbidity and mortality data from meconium aspiration syndrome in 103 infants, using combined DeLee and tracheal suction during a five-year period ( ), were also analyzed retrospectively. In spite of a combined

10 C2010 Worksheet:NRP-012A 31-Jan-2010.doc Page 10 of 16 DeLee and tracheal approach toward the prevention of meconium aspiration, the rate of meconium aspiration syndrome (2%) was not different in 1975 and Timing of obstetric DeLee suction (whether before or after delivery of the chest) did not influence the presence of meconium below the vocal cords (37 versus 36%, respectively). Even though significant morbidity remained associated with meconium aspiration in both periods studied, a drastic reduction occurred in neonatal mortality, from 46%, in 1975 to 12.5% in 1983, which was probably aided by major advances in perinatal care and supports routine prophylactic suctioning of meconium at birth. From these findings, we suggest that meconium aspiration syndrome is predominantly an intrauterine event secondary to fetal distress, and that DeLee and tracheal suctioning reduce only its severity. Comments: Retrospective study, assessing the combined approach. The effect of tracheal suctioning was not assessed independently. Though there was no change in incidence of MAS before and after using the combined approach the mortality rate decreased between the two periods supporting effect of tracheal suctioning on mortality. Fair, Neutral on MAS, LOE3, Fair, Supportive on mortality, LOE3. 9. A delivery room approach to the meconium aspiration syndrome (MAS). Immediate intubation, endotracheal suction, and oxygen administration can reduce morbidity and mortality Fox WW, Gutsche BB, DeVore JS Clin Pediatr 1977; 16:325-8 No abstract Comments: All infants who did not immediately breathe spontaneously (no numbers given) were intubated and suctioned through the endotracheal tube. 35 infants developed MAS. There were no deaths. This is compared to other studies that had high mortality. Poor study, information incomplete. No comparisons to no suctioned group. Poor, Supportive, LOE Meconium aspiration in infants- a prospective study Gregory GA, Gooding CA, Phibbs RH, Tooley WH J Pediatr 1974;85: No abstract Comments: Eighty infants were suctioned with 46 having meconium below the cords and 34 not. Though 34 did not have meconium below the cords, 7 had abnormal X-rays, but none got sick. Fifty percent (23) of those with meconium below the cords had abnormal X-rays with 16 of them getting sick. There were no deaths amongst these 80 patients who were suctioned compared to 2-3 deaths observed before suctioning was introduced. It would appear that suctioning did not prevent MAS occurring but reduced its severity therefore reducing mortality. Fair, Neutral for MAS, LOE 3; Fair, Supportive for mortality, LOE Meconium stained amniotic fluid: antenatal, intrapartum and neonatal attributes Gupta V, Bhatia BD, Mishra OP Indian Pediatr 1996; 33:293-7

11 C2010 Worksheet:NRP-012A 31-Jan-2010.doc Page 11 of 16 ABSTRACT: OBJECTIVES: To find out the incidence, outcome as well as antenatal, intrapartum and neonatal attributes of meconium stained amniotic fluid (MSAF). DESIGN: Prospective study. SETTING: Neonatal Unit of Hospital. SUBJECTS: 1426 live births occurring in 1500 consecutive deliveries, over one year period. INTERVENTIONS: In all babies born through MSAF, thorough oropharyngeal suction as soon as the head was delivered followed by immediate intratracheal intubation and suctioning in infants depressed at birth. RESULTS: 204 (14.3%) deliveries had MSAF of which thick meconium was present in 141. Hepatitis in mother, fetal distress during labor and intrauterine growth retardation were significant factors associated with MSAF. One fifth of babies born through MSAF suffered severe birth anoxia compared to 5.6% in non-msaf group. The consistency of meconium had direct bearing on the neonatal outcome. Severe birth asphyxia (SBA) occurred in 27.0 and 6.3% of babies with thick and thin meconium staining, respectively. Meconium aspiration syndrome was observed in 9 babies of thick meconium group and 8 of these were depressed at birth. All deaths occurred in thick meconium group and were associated with SBA. CONCLUSIONS: Selective approach can be adopted for babies with MSAF reserving intratracheal suctioning at birth for depressed neonate or evidence of fetal distress in utero. Rest of the neonates only need careful observation after thorough oronasopharyngeal suctioning. Comments: Depressed infants developed MAS despite having been suctioned. The Apgar score of suctioned infants is not stated, neither is the number of patients that were depressed and those who were suctioned. Poor, Neutral, LOE Delivery room management of meconium staining of the amniotic fluid and the development of meconium aspiration syndrome Hageman JR, Conley M, Francis K, Stenske J, Wolf I, Santi V, Farrell EE J Perinatol 1988;8: ABSTRACT: A 1-year prospective survey of obstetric and pediatric management of meconium staining of the amniotic fluid in 464 patients was undertaken. Pharyngeal suctioning before delivery was performed using bulb syringe (N = 130), De Lee suction catheter (N = 186), or both (N = 98); endotracheal intubation after delivery was also done in 413 instances. Using any of the three suctioning techniques, no differences were seen in Apgar scores, respiratory rates, presence or absence of meconium on or below the vocal cords, or development of meconium aspiration syndrome (MAS). If meconium was present on the vocal cords, it was present below the vocal cords in 76% of the cases. If no meconium was visualized, it was found below the vocal cords in only 7% of the cases. Of the 142 infants with meconium below the vocal cords, 10% developed MAS and all 14 survived. Comments: A large number of patients had meconium below the cords with a high number developing MAS, but there were no deaths. This is one of the studies that support the effect of tracheal suctioning in reducing mortality in those with MAS. Endotracheal intubation did not prevent MAS. Fair, Neutral for MAS, LOE 5. Fair, Supportive for mortality, LOE Incidence of meconium aspiration syndrome in term meconium-stained babies managed at birth with selective tracheal intubation Manganaro R, Mami C, Palmara A, Paolata A, Gemelli M J Perinat Med 2001;29:465-8

12 C2010 Worksheet:NRP-012A 31-Jan-2010.doc Page 12 of 16 ABSTRACT: 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 post term pregnancy and prenatal asphyxia is the best prevention of MAS. Comments: Only one depressed infant developed MAS. The number of infants who were depressed and therefore required intubation is not stated. Fair, Supportive, LOE A selective aggressive approach to the neonate exposed to meconium-stained fluid Peng TC, Gutcher GR, Van Dorsten JP Am J Obstet Gynecol 1996;175: ABSTRACT: OBJECTIVE: We attempted to determine the effect on meconium aspiration syndrome from a selective approach of neonatal endotracheal intubation in meconium-exposed fetuses. STUDY DESIGN: All pregnancies delivered at the Medical College of Virginia in 1990 were included. Meconium was noted at membrane rupture and qualified as thick, moderate, or thin. Neonates underwent suctioning with a DeLee device at delivery. They were observed without endotracheal intubation if they fulfilled the following criteria: vaginal delivery, gestational age > 37 weeks, birth weight > 2500 gm, and anticipated Apgar score > or = 8 at 1 minute. RESULTS: Of 4289 deliveries, 659 were exposed to meconium and 48% of infants were intubated. Birth weights, gestational ages at delivery, and umbilical arterial ph were similar between intubated and nonintubated neonates. Neonatal intensive care unit admissions were significantly higher in intubated neonates. All 9 neonates diagnosed with meconium aspiration syndrome were intubated at birth. CONCLUSIONS: Utilization of this protocol resulted in reduction of neonatal intubation. Meconium aspiration syndrome did not occur in the non-intubated group. Comments: The patients who developed MAS were from the group that was intubated (depressed infants). That means tracheal suctioning did not stop development of MAS among the depressed infants. Comparison made in this study does not address the question in this worksheet. Fair, Neutral, LOE Meconium aspiration syndrome: intrapartum and neonatal attributes Rossi EM, Philipson EH, Williams TG, Kalhan SC Am J Obstet Gynecol 1989;161: ABSTRACT: To identify the fetus and newborn at risk for meconium aspiration syndrome the perinatal characteristics of 238 infants delivered through meconium-stained amniotic fluid were prospectively examined. All infants with meconium-stained amniotic fluid were routinely suctioned with a DeLee apparatus before tracheal intubation and suctioning. The type and presence of meconium in the trachea, neonatal breathing before intubation, and Apgar scores were recorded in the delivery room. Intrapartum fetal monitoring data were collected for 80% (190/238) of the mothers and umbilical artery ph for 74% (177/238) of the newborns. Despite suctioning with a DeLee apparatus and endotracheal suctioning, meconium was present in the trachea in 87/238 (37%) and meconium aspiration syndrome developed in 22 (9.2%). A total of 73% of newborns who had

13 C2010 Worksheet:NRP-012A 31-Jan-2010.doc Page 13 of 16 meconium aspiration syndrome were delivered through thick meconium. Thick meconium, the presence of fetal tachycardia, and absence of intrapartum fetal cardiac accelerations identified the fetus at high risk for meconium aspiration syndrome. The presence of these monitoring findings and thick meconium should alert obstetricians to the possibility of a fetus that requires intervention. Low umbilical artery ph, Apgar scores less than 5, and meconium in the trachea further characterized the newborn at high risk for meconium aspiration syndrome. The combination of these findings may best identify the infant delivered through meconium-stained amniotic fluid who requires close observation for meconium aspiration syndrome. Comments: MAS occurred despite tracheal suctioning. Depressed infants are at high risk of developing MAS. Poor, Neutral, LOE Tracheal suction in meconium aspiration Ting P, Brady JP Am J Obstet Gynecol 1975;122: ABSTRACT: We performed a retrospective study of the morbidity and mortality rates of 125 infants, born through meconium-stained amniotic fluid, and admitted to the newborn intensive-care unit for observation. A comparison was made of maternal age, history of toxemia, type of anesthesia, duration of analgesia, presence of cord complications, abnormalities of fetal heart rate, duration of meconium staining, birth weight, gestational age, 1 and 5 minute Apgar scores, and type of resuscitation between infants who were symptomatic or asymptomatic in the unit. Forty-three developed respiratory distress (symptomatic) and eight died; 82 were asymptomatic. The only difference between the two groups was a history of immediate tracheal suction in the delivery room. Of 97 infants receiving immediate tracheal suction, 27 became symptomatic and one died--an infant with Down's syndrome and endocardial cushion defect. On the other hand, of 28 infants who did not receive immediate tracheal suction, 16 became symptomatic and seven died of massive meconium aspiration pneumonitis (P less than 0.001). We concluded that in infants born through meconiumstained amniotic fluid, immediate tracheal suction is a safe procedure that significantly lowers the morbidity and mortality rates and produces no further respiratory depression of the infant. Comments: This study compared the outcomes of patients who were suctioned to those who were not suctioned. It is not clear as to why some were suctioned and some were not. Tracheal suctioning reduced number of symptomatic (MAS) patients and mortality. Fair, supportive, LOE Risk factors for meconium aspiration syndrome Usta IM, Mercer BM, Sibai BM Obstet Gynecol 1995;86:230-4 ABSTRACT: OBJECTIVE: To identify potential predictors of meconium aspiration syndrome (MAS) in pregnancies complicated by moderate or thick meconium-stained amniotic fluid (AF). METHODS: In the period , 937 vertex singleton pregnancies with moderate or thick meconium-stained AF were delivered; of these, 39 neonates developed MAS and 898 did not. The two groups were compared retrospectively according to maternal findings, pregnancy outcome, and neonatal complications, using univariate analysis (P <.05 considered significant) and stepwise multiple logistic regression analysis to identify independent significant factors for prediction of MAS and to calculate odds ratios (OR) and 95% confidence intervals. RESULTS: The two groups had a similar mean gestational age at delivery and birth weight. They also had similar incidences of postdates pregnancies, small and large for gestational age infants, and amnio-infusion use. Univariate analysis identified significant differences between the two groups in 13 variables, two of which were

14 C2010 Worksheet:NRP-012A 31-Jan-2010.doc Page 14 of 16 excluded from logistic analysis because of inadequate data. Logistic regression analysis identified only six variables with independent, statistically significant effects on MAS: admission for induction with non-reassuring fetal heart tracing (OR 6.9), need for endotracheal intubation and suctioning below the vocal cords (OR 4.9), 1-minute Apgar score of 4 or less (OR 3.1), present cesarean delivery (OR 3.0), and previous cesarean delivery (OR 2.5). Cigarette smoking was associated with a lower risk for MAS (OR 0.07). The presence of at least one of the five risk factors had a sensitivity of 92%, a specificity of 56%, a positive predictive value of 8%, and a negative predictive value of 99% for MAS. CONCLUSION: Considering the high negative predictive value of the test, infants without any risk factors will not develop MAS and thus can be safely allowed to room with their mothers. Furthermore, this model helps to identify infants who may benefit from 24-hour observation and in counseling women about the neonatal risk for developing MAS. Comments: Depressed infants are at high risk of developing MAS. Need for tracheal intubation and suctioning increases the risk of MAS. Fair, Opposing, LOE Meconium aspiration syndrome: have we made a difference? Wiswell TE, Tuggle JM, Turner BS. Pediatrics 1990; 85: ABSTRACT: Meconium aspiration syndrome (MAS) and its associated complications are reviewed from the period before the routine use of intubation and suctioning to the present (1973 through 1987). Of the 176,790 neonates born during this period, the amniotic fluid was stained in 21,472 (12.15%). Subsequently, MAS developed in 1162 (5.41%) of the meconium-stained neonates. Male neonates were more prone to the disorder than female neonates (P =.022). There were no racial predilections for MAS. The incidence of MAS significantly decreased during the 15 years (P =.043). Of the neonates with MAS, 49 (4.22%) died as a direct consequence of the disorder. The death rate significantly declined during the study period (P =.041). Of the neonates with MAS, 345 (29.7%) required mechanical ventilation, and 134 (11.53%) had pneumothoraces. Among neonates with MAS, the requirement for mechanical ventilation, as well as the incidence of pneumothoraces, did not decrease from 1973 through The incidence of MAS has declined since the advent of combined obstetric and pediatric suctioning of the oropharynx and trachea. Furthermore, there are significantly fewer deaths from the disorder. These declines were likely influenced by other improvements in perinatal care, which have occurred since the early 1970s. The results do not support the contention that severe MAS and resultant deaths can be prevented altogether. Comment: Combined approach did not reduce incidence of MAS but did lead to reduction in deaths. Tracheal suctioning not studied separately. This study has compared two periods, therefore using some retrospective controls. It is not clear if reduction in mortality was due to changes in perinatal care or to implementation of combined approach. Fair, Neutral for MAS, LOE 3, Fair, Supportive for mortality, LOE Intratracheal suctioning, systemic infection, and the meconium aspiration syndrome Wiswell TE, Henley MA Pediatrics 1992; 89:203-6 ABSTRACT: A retrospective analysis was performed to determine: (1) the proportion of neonates with the meconium aspiration syndrome (MAS) who were not depressed at birth; (2) to evaluate the clinical course of neonates with MAS, particularly relating to whether or not delivery room intubation and intratracheal suctioning had taken place; and (3) to examine the incidence of culture-

15 C2010 Worksheet:NRP-012A 31-Jan-2010.doc Page 15 of 16 proven bacteremia among meconium-stained neonates and those with MAS. The medical records of all meconium-stained neonates and those with MAS admitted to our facility from 1985 through 1989 were reviewed. Of 5697 liveborn neonates, 741 (13%) were meconium-stained, of whom 608 (82%) were intubated and suctioned in the delivery room. No complications of the intubation/suctioning procedure were noted in these neonates. Forty-five neonates had culture-proven bacteremia. Five bacteremic neonates had been meconium-stained (0.7% of all such neonates), while 40 were not stained (0.8% incidence). Of 36 neonates with MAS, 1 (2.8%) was bacteremic. Twenty (56%) of 36 newborns with MAS did not require positive pressure ventilation in the delivery room. Twelve (33%) of the babies with MAS had not been intubated and suctioned in the delivery room. Nine (75%) of 12 nonsuctioned neonates, as well as 6 (25%) of 24 suctioned neonates, required mechanical ventilation for more than 6 hours (P =.010). Pneumothoraces occurred in 6 (50%) of 12 nonsuctioned and 5 (21%) of 24 suctioned babies (P =.125). Four of 12 nonsuctioned newborns either died (n = 1) or required extracorporeal membrane oxygenation (n = 3), while only 1 of the suctioned newborns required extracorporeal membrane oxygenation (P =.034 Comments: Infants born with meconium stained amniotic fluid and suctioned had better outcome than those not suctioned. Fair, Supportive, LOE Delivery room management of the apparently vigorous meconium-stained neonate: results of the multicenter, international collaborative trial. Wiswell TE, Ganon CM, Jacob J, Goldsmith J, Syzld E, Weiss K, Schutzman D, Cleary GM, Filipov P, Kurlat I, Caballero CL, Abassi S, Sprague D, Oltorf C, Padula M. Pediatrics 2000; 105:1-7 ABSTRACT: OBJECTIVE: Disagreement exists concerning the appropriate delivery room management of the airway of vigorous meconium-stained infants. Some suggest a universal approach to intubation and suctioning of the airway in all such neonates, whereas others advocate a selective approach. We performed this investigation: 1) to assess whether intubation and suctioning of apparently vigorous, meconium-stained neonates would reduce the incidence of meconium aspiration syndrome (MAS); and 2) to determine the frequency of complications from delivery room intubation and suctioning of such infants. METHODS: Inclusion criteria included: 1) gestational age >/=37 weeks; 2) birth through meconium-stained amniotic fluid of any consistency; and 3) apparent vigor immediately after birth. Subjects were randomized to be intubated and suctioned (INT) or to expectant management (EXP). Primary outcome measures included: 1) the incidence of respiratory distress, including MAS, and 2) the incidence of complications from intubation. RESULTS: A total of 2094 neonates were enrolled from 12 participating centers (1051 INT and 1043 EXP). Meconium-stained amniotic fluid consistency was similar in both groups. Of the 149 (7.1%) infants that subsequently demonstrated respiratory distress, 62 (3.0%) had MAS and 87 (4.2%) had findings attributed to other disorders. There were no significant differences between groups in the occurrence of MAS (INT = 3.2%; EXP = 2.7%) or in the development of other respiratory disorders (INT = 3.8%; EXP = 4.5%). Of 1098 successfully intubated infants, 42 (3.8%) had a total of 51 complications of the procedure. In all cases, the complications were mild and transient in nature. CONCLUSIONS: Compared with expectant management, intubation and suctioning of the apparently vigorous meconium-stained infant does not result in a decreased incidence of MAS or other respiratory disorders. Complications of intubation are infrequent and short-lived.

16 C2010 Worksheet:NRP-012A 31-Jan-2010.doc Page 16 of 16 Comment: Though this study excluded depressed infants which are the focus of our worksheet, of note is that the depressed infants were noted to be at high risk of developing MAS. Fair, supportive, LOE Meconium-stained amniotic fluid and respiratory complications: impact of selective tracheal suction Yoder BA, 1994 Obstet Gynecol 1994;83:77-84 ABSTRACT: OBJECTIVE: To determine prospectively the incidence of several pulmonary diagnoses among infants born through clear or meconium-stained amniotic fluid (AF) managed by a selective approach to tracheal intubation. METHODS: All live births greater than 36 weeks' gestation occurring between January 1990 and December 1992 were included. Diagnostic criteria for several respiratory disorders were determined prospectively and monitored. Infants with light meconium and vigorous infants with moderate to thick meconium were selectively not suctioned. A control group of infants with clear AF matched for gestational age and year of birth was randomly selected for comparison. The incidence and severity of respiratory disease were compared between the groups. RESULTS: Of 4938 live births, 799 (16%) had meconium-stained AF (light, 334; moderate to thick, 465). Compared to 211 infants with moderate to thick meconium selectively not suctioned, 196 suctioned infants had significantly greater rates of abnormal fetal heart rate (FHR) patterns, fetal acidosis, low Apgar scores at 5 minutes, need for resuscitation, and neonatal intensive care unit admission. Meconium aspiration syndrome was significantly more common in suctioned infants as compared to those selectively not suctioned, those with light meconium, and those with clear fluid (11 versus 3 versus 0 versus 0%; P <.01). The need for ventilator or oxygen support was similar between infants with clear fluid, lightly stained fluid, and moderate to thick fluid who were selectively not suctioned, but was significantly greater among suctioned infants (P <.01). CONCLUSIONS: We conclude that a selective approach to tracheal intubation and suction of infants with meconium-stained AF was not associated with increased pulmonary morbidity or mortality. Postnatal management of neonates at greatest risk of meconium aspiration syndrome does not necessarily prevent adverse pulmonary outcome. Comments: Selective tracheal suction in meconium stained amniotic fluid was not associated with increased morbidity. Meconium aspiration syndrome more common in suctioned infants, suctioning does not prevent adverse pulmonary outcomes. Fair, Neutral, LOE 4.