|ORIGINAL RESEARCH ARTICLE
|Year : 2020 | Volume
| Issue : 3 | Page : 98-104
Clinico-etiological profile of respiratory distress in the new-born and its out-come
Rohini Panigrahi, Kaustubh Samal, Gadadhar Sarangi, Prasant Saboth
Department of Pediatrics, Hi-Tech Medical College and Hospital, Bhubaneswar, Odisha, India
|Date of Submission||08-Jul-2020|
|Date of Decision||24-Oct-2020|
|Date of Acceptance||03-Nov-2020|
|Date of Web Publication||30-Jun-2021|
Dr. Gadadhar Sarangi
“THE CHILD”, B. K. Road, Ranihat, PO - Buxi Bazar, Cuttack - 753 001, Odisha
Source of Support: None, Conflict of Interest: None
Objectives: The objectives of the study are to estimate the incidence of respiratory distress (RD) with etiology and associated risk factors in newborns admitted to neonatal intensive care units and to propose adequate management plan for better clinical outcome. Study Design: This was a hospital-based prospective, longitudinal study. Setting: The study was conducted in a tertiary care teaching hospital of Odisha between November 2015 and October 2017. Study Population: A total of 202 newborns, born with RD, constitute the study population. The risk factors are delineated with outcome. Results: Out of 202 newborns with RD, 107 (53%) were males and 95 (47%) were females. Based on birth weight and gestational age, 35% were of very low birth weight (< 2000 grams; VLBW) and 19.8% were of low birth weight (2000 to <2500 grams; LBW). Both these groups accounted for 54.9% of all babies under the study. Pre-terms were 50.5% among VLBW and 9.9% among normal birth weight (NBW) babies. Most common etiology was found to be RD syndrome (RDS, 39.6%). 95% of cases survived while 5% resulted in death. 60% of the death was contributed by RDS and prematurity, while 40% of deaths were seen in term gestation with NBW resulting from birth asphyxia in this study. Although the death ratios in each group of newborns VLBW, LBW, and NBW were almost equal, the etiology of RD and death in the respective groups was different. Conclusion: The study shows an association between mortality and onset of RD. Early onset of RD increases mortality. Antenatal steroid administration has a positive outcome. VLBW and LBW newborns succumb more to RD. The etiology of RD is different in different categories of birth weight. Continuous positive airway pressure is the cornerstone in management of RDS.
Keywords: Birth asphyxia, hyaline membrane disease, neonatal respiratory distress, transient tachypnea of newborn
|How to cite this article:|
Panigrahi R, Samal K, Sarangi G, Saboth P. Clinico-etiological profile of respiratory distress in the new-born and its out-come. J Pediatr Assoc India 2020;9:98-104
|How to cite this URL:|
Panigrahi R, Samal K, Sarangi G, Saboth P. Clinico-etiological profile of respiratory distress in the new-born and its out-come. J Pediatr Assoc India [serial online] 2020 [cited 2022 Dec 9];9:98-104. Available from: http://www.jpai.in//text.asp?2020/9/3/98/320120
| Introduction|| |
The neonatal period (the first 28 days of life) carries the highest risk of mortality than any other period during the childhood. India contributes to one-fifth of global live births and more than a quarter of neonatal deaths. The first 24 h accounts for more than one-third (36.9%) of the deaths that occur in the entire neonatal period. Respiratory disorder is the most frequent cause of admission in neonatal intensive care unit (NICU) and contributes as one of the most common causes of morbidity and mortality in the neonatal period. The spectrum of respiratory distress (RD) in neonates includes transient tachypnea of newborn (TTNB), pneumonia, RD syndrome (RDS), meconium aspiration syndrome (MAS), sepsis, congenital heart disease (CHD), some surgical pathology of the lungs, esophagus, and diaphragm, and other miscellaneous causes. Regardless of the cause, if not recognized and managed quickly, RD can escalate to respiratory failure and cardiopulmonary arrest. Therefore, it is imperative that any healthcare providers caring for newborn infants should readily recognize the signs and symptoms of RD, differentiate various causes, and initiate management strategies to prevent significant complications or death.
The present study is designed to know the incidence of RD along with the etiology and the outcome among the newborns admitted to the NICU. The objective is to assess and stabilize a newborn infant with RD and provide adequate treatment to prevent neonatal mortality.
Aims and objectives
(1) To find out the etiology, signs and symptoms, and risk factors associated with severe RD. (2) To recognize and differentiate clinical and radiological profile in TTNB, neonatal pneumonia, RDS, and MAS. (3) To study the preventable and salvageable mortality due to RD and to formulate a strategic plan for optimal management in resource-poor settings.
| Material and Methods|| |
Place of study
The study was conducted at the NICU of Department of Pediatrics, Hi-Tech Medical College and Hospital, Bhubaneswar, Odisha. It is a city-based teaching hospital with a delivery rate of 1000 per year.
A total of 202 neonates delivered in the above institution and referred from outside with RD and meeting the inclusion criteria are included in the study.
The study was conducted between November 2015 and October 2017.
This is a perspective, hospital-based longitudinal study.
Babies delivered after 28 weeks of gestation till 28 days of life with two or more clinical pictures of RD such as tachypnea, chest wall retractions (subcostal, intercostals, suprasternal), apnea, grunting, cyanosis at room air in two consecutive examinations 1 h apart, and gasping.,
Postoperative RD, syndromic neonates, systemic congenital malformations (TOF, cardiac disease, diaphragmatic hernia, etc.), less than 28 weeks of gestation, birth weight <1000 g, and where parents refused to admit in the study.
Detail family history, obstetric history, and history of labor and delivery were recorded.
Birth weight and gestational age assessment were done and recorded.
Continuous oxygen saturation monitoring with pulse oximeter and arterial blood gas (ABG) measurement, oxygen administration, and continuous positive airway pressure (CPAP) ventilator setting with dexamethasone administration as and where necessary were also done.
Taking the incidence in population as 0.2 (P) (20%) and level of confidence as 5% (d), substituting in the formula, the number is equal to Z2 (1 − α/2) × P (1 − P)/d2 = 1.96 × 0.2 (1 − 0.2)/0.052 = 202.
Demographic characteristics of mothers under study such as age, gender, education, socio-economic status etc were recorded. When the variable had two categories, nonparametric binomial test was done to test the equality of proportions, and where three or more categories were present, nonparametric Chi-square test was done to test the equality of proportions. Distributions of RD cases by risk factors and onset of RD were also done using frequency procedure along with nonparametric binomial test of equality of proportions. The distribution of cases by gestational age and birth weight, signs and symptoms of RD, chest-X ray findings, invasive and noninvasive investigations, and etiology of RD was done using cross-tabulation process, and their association was studied using Chi-square test of independence. Association of onset of RD with gestational age, outcome versus onset of RD, association of antenatal steroid with outcome, birth weight, and outcome was studied using cross-tabulation procedure along with Chi-square test of independence. The significant cutoff value has been taken as < 0.05 for test of significance.
| Observations|| |
According to the demographic profile of the mothers and the newborn with respiratory distress
Majority of the mothers were in the age group 20–28 years which accounts for 85.6% of the cases and the remaining 14.4% were in age group of ≥29 years (P < 0.001). Out of 202 newborn with RD, 107 were males (53%) and 95 (47%) were females. The male and females in the sample were evenly distributed (P = 0.439). The socioeconomic status of the mothers revealed that most belonged to upper middle class (49.5%). Upper lower and lower middle classes are comprised of 25.2% cases each. The upper middle-class group was significantly higher (P < 0.001). The detailed analysis is represented in [Table 1].
According to the risk factors associated with the newborn
Majority of the newborns with RD were born to primigravida mothers accounting for 74.8% while 25.2% were multipara (P < 0.001). Similarly, significant proportion of delivery was C-section, contributing 75.2% of the cases (P < 0.001). However, all the cases were institutional delivery taking place in the hospital [Table 2].
Distribution of cases by gestational age and the birth weight
Out of 202 cases, 71 (35.1%) were very low birth weight (VLBW) babies, 40 (19.8%) were LBW babies, and 91 (45%) were with normal weight. VLBW and LBW together accounted for 54.9% of the cases. Among the LBW and VLBW babies, 50.5% were preterm, and among the normal birth weight (NBW) babies, 9.9% were preterm. This strongly indicates that birth weight and gestational age have significant association (P < 0.001).
Preterm delivery is found to be higher with VLBW and LBW babies [Table 3].
Distribution of respiratory distress cases by maternal risk factors
Premature rupture of membrane (PROM) was found among half of the cases. About 30% mothers had a history of hypertension, 35% had meconium-stained liquor, and 34.7% had a history of taking antenatal steroids. Maternal pyrexia was observed in 14.9% of cases, 10.4% mothers had diabetes mellitus (DM), and 9.9% mothers were observed to have foul smelling liquor [Table 4].
|Table 4: Distribution of respiratory distress cases by maternal risk factors|
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Onset of respiratory distress
79.7% of cases had early-onset RD within 24 h of birth.
Signs and symptoms of respiratory distress
Most frequent signs of RD were tachypnea and upper chest in-drawing with 75.2% each. Flaring of alae nasi was present in 70.3% of cases. Lower chest in-drawing, grunting, cyanosis, and reduction in the bilateral air entry were found in variable numbers [Table 5].
|Table 5: Distribution of cases by signs and symptoms of respiratory distress|
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Chest X-ray findings in respiratory distress
In chest X-ray findings, TTNB was observed in 160 (80.2%) cases out of total 202 cases. Varying grades of hyaline membrane disease (HMD) changes was observed in 50% of cases (101). Infiltration was seen in 5% of hyperinflated lung field in 10.4% and pneumothorax was observed in 10 cases (5%).
Invasive and noninvasive investigations in respiratory distress
Pulse oximetry was found abnormal in three-fourth of the cases. About a quarter had sepsis screen positive. Blood culture was found positive among 15.3% of the cases. ABG was abnormal among 44.6% of the cases. Abnormal serum electrolyte was found among 24.8% of the cases. Blood glucose was found abnormal in 15.3% of cases. ECHO and transcranial ultrasonography (USG) were abnormal among 5% of the cases. In 9.9% of babies, the cerebro-spinal fluid (CSF) study were found abnormal [Table 6].
|Table 6: Distribution of cases by invasive and noninvasive investigation|
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Distribution of cases by etiology of respiratory distress
Most common etiology was found to be RDS (39.6%) followed by sepsis (30.2%), TTNB (25.2%), and apnea of prematurity (24.8%). MAS and birth asphyxia were found in 15.3% and 10.4% of the cases, respectively. Other etiology was critical CHD, pneumothorax, persistent pulmonary hypertension of the newborn (PPHN), and pneumonia each found in 5% of the cases [Table 7].
Distribution of cases by modality of therapy
Oxygen support was given to all cases. 40.65% of cases need oxygen support for less than 1 day while 29.7% required between 2 and 5 days and 29.7% required > 5 days. Ventilator support was required in quarter of the cases. Surfactant was given 20.3% of cases and CPAP support was required in 14.9% of cases [Table 8].
Outcome of respiratory distress
Out of total cases (202), 192 cases (95%) survived while 10 cases (5%) succumbed.
Association of respiratory distress with gestational age
101 cases had preterm delivery out of which 89.1% had RD with within 24 h of birth. Among 90% of cases of term delivery, 66.7% had onset <24 h of birth, and all 11 cases of postterm delivery had onset of RD ≤24 h. The preterm and postterm babies had significantly higher prevalence of RD <24 h of birth (P < 0.001).
Association of respiratory distress with onset
It was found that mean RD score for cases with onset <24 h was 5.92 ± 1.7999 and that for cases ≥24 h was 5.51 ± 1.121. The difference was found to be nonsignificant with P = 0.169.
Association of outcome with onset of respiratory distress
All the deaths were found among the RD cases with the onset of <24 h. This indicated an early onset of RD with mortality. However, this needs to be verified with larger samples before arriving at any definite conclusion as there was no death in the RD cases with onset of more than 24 h.
Distribution of cases by APGAR score
The distribution of cases by APGAR score at 1 and 5 min of delivery. At 1 min, APGAR score <7 was found among 80 (39.6%) cases. However, at 5 min, this proportion was 65.3% [Table 9].
|Table 9: Distribution of cases by appearance, pulse, grimace, activity, and respiration score|
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Association of antenatal steroid with outcome
Seventy cases whose mothers had received antenatal steroids had a survival rate of 100%, while 122 cases whose mothers did not receive antenatal steroids had a survival rate 92.4% and 10 (7.6%) resulted in death. The antenatal steroid was found to have significant association with better survival in RD cases (P < 0.002).
| Discussion|| |
This study having a sample size of 202 is more than the sample size of the studies by Barkiya et al. and Swarnkar et al. A higher percentage of mothers in the study were in the age group of 22–28 years and 14.4% still in the age group >30 years. In studies mentioned above, mothers in the age group of <21 years ranging from 18% to 27%, in the age group 22–30 years ranging from 60% to 69%, and in the age group of above 30 years 5%–15% are described. This implies that the childbearing age in this study population was higher than the childbearing age of the other study population. In the present study, the male: female ratio of RD cases was 53:47 which is more or less similar with others.
This study shows that 74.8% of RD cases were born to primigravidas and 25.2% were born to multipara. In the study conducted by Chandrasekhar et al., they showed that multipara were 60% and primipara were 40%. A significant proportion of RD cases were born by C-section, contributing to 75.2% of the total cases in this study. Similar results were also seen in Chandrasekhar et al. (75%), depicting C-section as a predominant factor associated with RD in newborn. This study showed that nearly 55% of cases with RD cases were either VLBW or LBW babies as compared to 45% of newborns who were normal for gestational age. Similar findings were seen in the study of Chandrasekhar et al. and Patil Ravindra et al., where the percentage of LBW and VLBW together accounted to 60% and 50%, respectively, of the NICU admission with RD. The present study also showed that majority of the cases were preterm (50%), which was similar to findings of studies by Barkiyaet al. and Santosh et al. Literature and results from given studies show that the risk of RD markedly increased with prematurity and decreased birth weight as compared to babies who had NBW which augments the risk of mortality from RD cases. Hence, it is essential to keep an eye over neonatal services to reduce prematurity, which is a common cause of LBW and VLBW in newborns, predisposing to increased neonatal mortality from RD.
A large number of variations were seen in maternal risk factors in similar studies conducted. Nearly half of the mothers were affected with PROM in the present study, which was relatively very high as compared to other similar studies. 30% of the mothers were affected by hypertension. Meconium-stained amniotic fluid, maternal pyrexia, DM, and history of foul-smelling liquor were present in 35.1%, 14.7%, 10.4%, and 9.9%, respectively, in this study population.
Nearly 50%–55% of the cases in this study with RD were premature, LBW, and VLBW newborns. This demonstrates the relationship between varied maternal diseases and RD in newborn, probably because the infants of mothers with maternal diseases are commonly subjected to predisposing insults, which results in prematurity and LBW. This represents the real risk factor for early neonatal morbidity.
Nearly four-fifth of the patients developed RD within 6 h of life, almost similar to the study conducted by Barkiya et al.
Most frequent sign of RD was flaring of alae nasi affecting 98.2% and tachypnea affecting 95.5% of the study population. This finding was similar to Parkash et al. where all patients developed tachypnea and flaring of alae nasi. Chest in-drawing was seen in 86.3% in the present series which is almost similar to the other studies. Grunting affected 64.9% and cyanosis was seen in 70.3% of the study population. According to the study conducted by Swarnkar et al., it was found that grunting and flaring of alae nasi had high specificity for neonatal RD while tachypnea, chest retractions, and difficulty in feeding had high sensitivity for diagnosis.
Failure to recognize the common signs and symptoms of RD and delay in the institution of appropriate, judicious, and timely treatment may progressively lead to respiratory failure and death in newborn. Hence, identifying early features of RD is of paramount importance to reduce neonatal morbidity and mortality.
HMD of varying grades was found among 39.6% of the cases in this study. Hyperinflated lungs were noticed among 30.2% of cases. Parenchymal infiltration and pneumothorax were observed among 5% newborns, respectively. Chest X-ray is one of the main steps in RD diagnostic procedure. Being the most usual and accessible early diagnostic tool, it helps in early identification of the cause and institution of appropriate management.
Pulse oximetry showed subnormal oxygen saturations in all patients with RD. ABG showed abnormalities in 55.4% of the patients, reflecting electrolyte imbalance commonly affecting newborns with RD. Sepsis screen and blood culture were positive in 25.2% and 15.3% of patients, respectively, correlating to the etiological outcome of this study. ECHO showed cardiac abnormality in 5% of the babies showing ostium primum atrial septal defect, ventricular septal defect, and patent ductus arteriosus. Abnormal transcranial USG was seen in 5% of neonates. This shows that invasive and noninvasive diagnostic modalities help in early detection as well as monitoring of treatment in cases with RD. Hence, they should be included as an important tool for the diagnosis and management of RD. Most common etiology found in this study was RD syndrome, corresponding to 39.6% of the newborns followed by 30.2% being TTNB. The incidence of RD syndrome is highest in this study as compared to the other similar studies. 50% of newborns in the study were preterms with LBW and VLBW. Out of which, more than one-third of cases developed RDS. Patil Ravindra et al., Santosh et al., and Barkiya et al. each showed 37.3%, 31.5%, and 24% of RDS cases, respectively, in their studies.
Nearly one-fourth of newborns in this series were affected with sepsis, which was relatively higher than other similar studies. In this series, it is an important cause of morbidity in neonates. A systematic analysis of global, regional, and national causes of child mortality in 2013 identiﬁed preterm birth complications and infections to be the two major causes of neonatal deaths in India, accounting to 43.7% and 20.8%, respectively., More than 80% of total neonatal deaths occur among LBW/preterm neonates,, which correlates with the findings of the present study population.
TTNB was encountered in 30.2% of the newborns, all being born at term, which was 44.5% of the total cases studied. 10.4% of the neonates with RD were affected with birth asphyxia, which was almost similar to other similar studies conducted. Birth asphyxia not only leads to neonatal deaths but also accounts for a signiﬁcant proportion of neonatal morbidity. The reported incidence varies from 2% to 16.2% in community-based studies. Suffix 'respectively' all after sentence ending xxx birth asphyxia. 15.3% of the cases suffered with MAS which ranged between 5% and 31%, among other studies. The greater incidence of MAS in developing countries like India reflects the poor-quality and inadequate obstetrical care.
One-fourth of the cases had apnea of prematurity as a cause of RD which was exclusively seen in preterm births. PPHN and CHD each were responsible for 5% of the etiology. The incidence of CHD was higher in this study, as compared to Patil Ravindra et al., Santosh et al., Barkiya et al., and Swarnkar et al. Pneumothorax was seen in 5% of newborns. Pneumothorax usually develops secondary to an underlying disease process but can also occur spontaneously in 5% of the newborns around the perinatal period; however, only 10% of them are symptomatic. Bronchopulmonary dysplasia was seen in nearly 10% of the newborns.
RDS was the primary etiology for RD and 60% mortality in the present study was attributed to it, which was seen in premature LBW and VLBW babies. In term newborns, RDS, pneumonia, intrapartum-related hypoxia, and MAS were the main causes of RD.
Oxygen therapy was given to all newborns admitted to the NICU with RD. Majority of the newborns (40.6%) needed oxygen therapy for less than 1 day, while 29.7% newborns needed oxygen support for 2–5 days and similar number for more than 5 days. 25.2% of the newborns were put on ventilator support, and CPAP was given in 14.9% of babies. Respiratory support to treat RD was provided by CPAP or mechanical ventilation. Surfactant was also used in 20% preterms presenting with severe RDS. However, it was found that the high cost and the need for endotracheal intubation for its administration made surfactant unsuitable for low-resource settings. Mechanical ventilation is expensive and requires a high level of expertise. CPAP was found to be the only intervention which has the potential to be implemented on a large scale. It was found to be one of the best forms of treatment in mild-to-moderate cases of RDS. In this study, no deaths were encountered with the management with CPAP, while all deaths due to RDS were in severe forms with associated risk of sepsis and asphyxia that were given mechanical ventilation as respiratory support. Studies conducted by Patil Ravindra et al. and Santosh et al. had a mortality rate of 17.6% and 7.8%, respectively. A lesser mortality rate of 5% was documented in this study which is less compared to other studies. This may be due to early diagnosis, use of improved life-saving modalities of treatment like CPAP, and timely management done in cases with RD which has resulted in decreased mortality among newborns in this study.
| Conclusion|| |
An association was found between gestational age and the duration of onset of RD. Prematurity may be a predisposing risk factor for the development of RD early within 6 h of life
All deaths found among the RD cases had an onset of RD within 24 h of life. This indicates that an early-onset RD has high mortality. However, the small number of deaths in the present series is insufficient for conclusion and needs further elucidation
The antenatal steroid administration to the mothers was found to have significant association with better survival from RD cases (P = 0.0018)
This study shows a greater incidence of mortality with decrease in birth weight. 60% death in this study was attributed to RDS affecting premature, LBW, and very low birth babies as a primary cause of death associated with birth asphyxia and sepsis as comorbid conditions. 40% of the deaths were seen in term gestation with NBW > 2.5 kg resulting from birth asphyxia. Hence, RDS is the most common cause of morbidity and mortality in preterm LBW babies and birth asphyxia is the most common cause of death in term newborns
Although the death rates in each group of newborns VLBW, LBW, and NBW were almost equal, the etiology of RD and death in the respective groups was different
The neonatal mortality rate in India due to prematurity and its complication is 43.7% and due to intrapartum-related causes, perinatal birth complication, and birth asphyxia is 19.8%. 40% of death in this study was seen in term gestation with normal birth weight, resulting from birth asphyxia. There is a significant increase in mortality due to birth asphyxia in this study
According to this study, LBW and prematurity are the common causes for admission in the NICU for RD. RDS, TTNB, sepsis, MAS, and birth asphyxia were the important and leading causes of morbidity in this study. The most common causes for mortality were prematurity, RDS, and birth asphyxia.
The incidence of RDS is highest in this study as compared to the other similar studies. One-third of cases of preterms, LBW, and VLBW developed HMD, emphasizing that most common cause of morbidity in preterms is HMD. Strong evidence reveals an inverse relationship between gestational age and respiratory morbidity
40% of death in this study was attributed to birth asphyxia in term, NBW babies weighing >2.5 kg. This proportion of deaths in term gestation due to perinatal birth complication and birth asphyxia is completely salvageable by appropriate obstetrical care and timely intervention
Noninvasive modalities of treatment like CPAP is a cornerstone in the treatment of mild-to-moderate cases of RDS in low-middle income setups where other expensive modalities of treatment are not feasible. Its affordability and feasibility with good safety profile make it the treatment of choice in resource-poor settings.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
| References|| |
Sankar MJ, Neogi SB, Sharma J, Chauhan M, Srivastava R, Prabhakar PK, et al
. State of newborn health in India. J Perinatol 2016;36:S3-8.
Santosh S, Kumar K, Adarsha E. A clinical study of respiratory distress in newborn and its outcome. Indian J Neonatal Med Res 2013;1:2-4.
Morton SU, Brodsky D. Fetal physiology and the transition to extrauterine life. Clin Perinatol 2016;43:395-407.
Barkiya SM, Venugopal N, Kumari V. Clinico-etiological profile and outcome of neonatal respiratory distress. Int J Sci Stud 2016;3:189-92.
Swarnkar K, Swarnkar M. Neonatal respiratory distress in early neonatal period and its outcome. Int J Biomed Adv Res 2015;6:643-64.
Chandrasekhar R, Mohan MM, Vijaya Lakshmi B. Clinical study of respiratory distress in newborn. Int J Contemp Pediatr 2016;3:910-5. [Doi: org/10.18203/2349-3291.ijcp20162364].
Patil Ravindra B. Clinical profile and outcome of babies admitted to neonatal intensive care unit (NICU), Mc Gann Teaching Hospital Shivamogga, Karnataka: A longitudinal study. Sch J App Med Sci 2014;2:3357-60.
Parkash A, Haider N, Khoso ZA, Shaikh AS. Frequency, causes and outcome of neonates with respiratory distress admitted to Neonatal Intensive Care Unit, National Institute of Child Health, Karachi. J Pak Med Assoc 2015;65:771-5.
Liu L, Oza S, Hogan D, Perin J, Rudan I, Lawn JE, et al
. Global, regional, and national causes of child mortality in 2000-13, with projections to inform post-2015 priorities: An updated systematic analysis. Lancet 2015;385:430-40.
Million Death Study Collaborators, Bassani DG, Kumar R, Awasthi S, Morris SK, Paul VK, et al
. Causes of neonatal and child mortality in India: A nationally representative mortality survey. Lancet 2010;376:1853-60.
Chaudhari S, Bhalerao MR, Chitale A, Pandit AN, Nene U. Pune low birth weight study--A six year follow up. Indian Pediatr 1999;36:669-76.
Paul VK, Sachdev HS, Mavalankar D, Ramachandran P, Sankar MJ, Bhandari N, et al
. Reproductive health, and child health and nutrition in India: meeting the challenge. Lancet 2011;377:332-49.
Vento M, Saugstad OD. Resuscitation of the term and preterm infant. Semin Fetal Neonatal Med 2010;15:216-22.
Dewez JE, van den Broek N. Continuous positive airway pressure (CPAP) to treat respiratory distress in newborns in low- and middle-income countries. Trop Doct 2017;47:19-22.
[Table 1], [Table 2], [Table 3], [Table 4], [Table 5], [Table 6], [Table 7], [Table 8], [Table 9]