Causes, risk factors and outcomes in neonates with respiratory failure

Objectives: To determine some causes, risk factors and outcomes in neonates with respiratory failure. Subjects and methods: A descriptive and prospective study on 139 neonates who were diagnosed respiratory failure after birth (case group) and 278 neonates without respiratory failure (control group) were admitted in Pediatric Department, Bachmai Hospital.

CAUSES, RISK FACTORS AND OUTCOMES IN NEONATES

WITH RESPIRATORY FAILURE

Nguyen Thanh Nam*; Cao Thi Bich Hao*

Pham Van Dem**; Dong Khac Hung***; Nguyen Tien Dung* Summary

Objectives: To determine some causes, risk factors and outcomes in neonates with respiratory failure Subjects and methods: A descriptive and prospective study on 139 neonates who were diagnosed respiratory failure after birth (case group) and 278 neonates without respiratory failure (control group) were admitted in Pediatric Department, Bachmai Hospital Results: Mortality rate in neonates was 15.1% The average of gestational age in neonates with respiratory failure was 34 weeks, significantly lower than the control group with 38 weeks (p < 0.001) The mean birth weight of case group (2,057 Gr) was significantly lower than control group (2,893 Gr) (p < 0.001) The most causing respiratory failure was respiratory disease 38.9%, premature 30.9% The relative risk in neonates without risk factor was 0.24 Co-operated with pediatrician in neonates with risk factor of case group (64.7%) was significantly higher than control group (30.9%) Asphyxia rate at 1 st mimute after birth of control group (11.2%) was significantly lower than case group (69.1%) (p < 0.001) Respiratory distress in newborn babies who have Apgar score at 1 st minute ≤ 7 points was 17.8 Respiratory distress in newborn babies who were delivered by elective cesarean section without labour was 40.3 Respiratory distress in newborn babies whose mothers suffered from disease was 3.7 Conclusion: The mortality was high in neonates with respiratory failure The most causing respiratory failure was respiratory disease Premature, low birth weight increased respiratory failure In addition, asphyxia rate after birth, delivered by elective cesarean section without labour and mother’s disease were common risk factors of respiratory distress in neonates Co-operation between obstetrician and pediatrician are very important

* Keywords: Neonates; Respiratory failure; Causes; Risk factors

INTRODUCTION

Respiratory failure is a common disease

in neonates and is a common cause of

treatment in neonatal intensive care unit

There are many diseases such as hyaline

membrane disease; meconium aspiration

syndrome; pneumonia; pulmonary

hemorrhage, congenital heart defects [2]

There are many factors that affect the rate

of neonates with respiratory failure such

as maternal disease, problems at delivery, premature birth, cesarean delivery (CS), especially CS without labour, neonatal resuscitation [5, 7] these factors can be intervened to reduce the risk factors of respiratory failure The objectives of the

study is to: Find some causes, treatment

results and factors affecting in neonatal respiratory failure

* Bachmai Hospital

** Vietnam National University Hanoi

*** Vietnam Military Medical University

Corresponding author: Nguyen Thanh Nam (bsntnam@gmail.com)

Date received: 30/07/2017 Date accepted: 09/09/2017

SUBJECTS AND METHODS

1 Subjects

- Case group: 139 neonates who were

born at Department of Obstetrics - Bachmai

Hospital and were diagnosed as respiratory

failure, hospitalized and treated at Neonatal

Intensive Care room at Department of

Pediatrics, Bachmai Hospital from 1 - 2013

to 12 - 2015 Acute respiratory failure is

defined as lung dysfunction, causes failure

at gas exchange, oxygen is decreased

and carbon dioxide is increased, so the

lung is not able to hold on Pa02, PaC02

and pH in threshold criteria [2] Diagnosis

of acute respiratory failure based on

clinical and paraclinical symptoms

Clinical symptom of respiratory failure

[1, 2]: respiratory failure is defined as one

of the signals: respiratory distress:

tachypnoea > 60 breaths/min or slow

breathing < 40 breaths/min; chest wall

recessions, paradoxical movement of the

chest wall; nasal flaring; grunting or apnoea,

cyanosis; Apgar score after birth at

1 minute, 5 minutes based on heart rate,

respiratory effort, muscle tone, response

to stimulation and skin coloration (total

score: ≤ 3: severe asphyxia, 4 - 6 points:

moderate asphyxia, ≥ 7: normal) Subclinical

symptoms: blood gases are criteria for the diagnosis of acute respiratory failure [2]: Pa02 < 60 mmHg, and/or PaCO2 > 50 mmHg and pH < 7.1 - 7.2; chest X-ray [1]: normally, bilateral lungs enlarge badly, ground-glass opacity nodules, stagnant air bronchograms

- Control group: 278 neonates at Department of Obstetrics who were moved

to the neonatal room at Department of Pediatrics, Bachmai Hospital without respiratory failure from 1 - 2013 to 12 - 2015

2 Methods

Descriptive and prospective study

RESULTS

1 General characteristics of the groups

From January, 2013 to December, 2015,

we evaluated 139 neonates with respiratory failure and 278 neonates without respiratory failure who were treated at Department of Pediatrics The average gestational age

of the case group (34 weeks) was significantly lower than the control group with 38 weeks (p < 0.001) The average weight of the case group (2,057 Gr) was significantly lower than the control group with 2,893 Gr (p < 0.001)

Chart 1: Gestational age distribution in the study

In 139 neonates with respiratory failure, 28% of the neonates were smaller than

32 weeks while in the control group, 0.4% of the neonates were smaller than 32 weeks Neonates without respiratory failure were primary as full term infants So prematrure infants had significantly higher risk of neonatal respiratory failure (p < 0.001)

Table 1: Some common causes of respiratory failure

In 139 neonates with respiratory failure who were required mechanical ventilation, the cause of lung was 38.9% and asphyxia had the largest number Congenital heart defects were primary as patent ductus arteriosus, pulmonary arteria hypertension Premature infant was a cause which had high rate with 30.9 percent of neonates with respiratory failure

Chart 2: Results of treatment for respiratory failure

In 139 neonates with respiratory failure, the discharged rate was 84.9%, the mortality rate was 21 (15.1%)

Table 2: Relationship between neonatal weight and respiratory failure

Groups Weight

(95%CI)

(3.429 - 8.267)

The lower neonatal weight was, the higher rate of respiratory failure was In this

study, the rate of respiratory failure in the low birth weight group was 65.5%, while the

rate of low birth weight in the control group was significantly smaller than 26% (p < 0.001) If neonatal weight is smaller than 2,500 Gr, neonates will have a risk of

respiratory failure is 5.324 (95%CI; 3.429 - 8.267)

Table 3: Role of co-operation with pediatrist in neonatal resuscitation

Groups Pediatrician

(95%CI)

(0.158 - 0.375)

Neonates who were not at risk had a rate of respiratory failure (35.5%) was

significantly lower than control group (69.1%) (p < 0.001) Neonate was not at risk

whose risk of postpartum respiratory failure was only 0.244 (95%CI; 0.158 - 0.375)

Table 4: Apgar scores at the first minute and respiratory failure

Groups Apgar scores

(95%CI)

(10.592 - 29.875)

Apgar score at the first minute  7 in the control group had higher rate than in the

case group (69.1% vs 11.2%) (p < 0.001) Children with Apgar score at the first minute

 7 had a risk of respiratory failure (17.888) (95%CI; 10.592 - 29.875) As a result, the

baby's appearance of asphyxia immediately after birth (the first minute) warns the risk

of respiratory failure in the next hours

Table 5: CS without labor and the rate of respiratory failure

Groups

CS without labour

(95%CI)

(15.631 - 103.736)

Cesarean delivery without labour had a significant effect on the risk of postpartum respiratory failure (p < 0.001) The risk of neonatal respiratory failure was 40.268

(95%CI; 15.631 - 103.736) CS without labour

Table 6: The effect of maternal factors on the postpartum respiratory failure

Groups Maternal factors

(95%CI)

History of maternal

pregnancy

(1.012 - 2.641)

Maternal disease

during pregnancy

(0.954 - 2.16)

Maternal problem at

delivery

0.001

3.725 (2.417 - 5.743)

History of maternal pregnancy was associated with postpartum respiratory failure (p = 0.043) The risk of postpartum respiratory failure was 1.635 (95%CI; 1.012 - 2.641) times when the mother had a history of abnormal pregnancy Maternal disease during pregnancy was not associated with postpartum respiratory failure (p = 0.083) Maternal problem during labor had an effect on the incidence of postpartum respiratory failure (p < 0.001) The risk of pediatric respiratory failure was 3.725 (95%CI: 2.417 - 5.743) times when mothers had medical diseases during labor

DISCUSSION

The study was carried out from 1 - 2013

to 12 - 2015, 139 neonates who were

diagnosed as respiratory failure were

transferred from the Department of

Obstetrics to the Neonatal Intensive Care

Unit room at Department of Pediatrics,

Bachmai Hospital for treatment During

the admission process, we evaluated and

exploited the maternal history and recorded

the factors related to the pregnancy and

childbirth to find out some causes and risk

factors related to the possibility of being

respiratory failure of the baby after birth

In 139 neonates who were diagnosed

as respiratory failure hospitalized, the causes

of the disease varies from lung and respiratory

diseases (hyaline membrane disease,

asphyxia, meconium aspiration syndrome,

pneumonia ), cardiovascular disease (patient ductus arteriosus, pulmonary hypertension ), respiratory failure in premature birth However, the rate of lung disease, respiratory disease and respiratory failure in premature birth was still high, 38.9% and 30.9% respectively These pathologies are potentially preventable and treatable if the prognosis

of the risk factors that affects the respiratory status of the postnatal children to timely therapeutic intervention, limiting the negative impact on the respiratory function of children when they begin to adapt to life outside uterus This is the role of management of pregnancy and childbirth in the per partum and postpartum period, especially in the per partum period, which directly affect infant’s status In our study, the obstetric history of the mother (giving birth prematurely, miscarriage, fetal death, etc.) had an effect

on neonatal respiratory failure risk (p = 0.043),

risk of neonatal respiratory failure was

OR = 1.635 (95%CI; 1.012 - 2.641) when

the mother has a history of abnormal

pregnancy Huynh Thi Duy Huong had

detail risk factor of respiratory distress

such as: fetal death… [2] The common

complications during CS were hypertension,

cardiovascular disease, renal failure,

systemic disease (lupus), pregnancy toxicity,

preeclampsia, HELLP syndrome… If these

conditions were detected and controlled, it

would reduce the risk of postpartum

respiratory failure Maternal health factors

as risks for postnatal child were also reported

by foreign authors such as Khairy et al who

found that pregnant women with congenital

heart had risk factors that directly affected

their health and their infants, in which

giving birth prematurely and respiratory

distress accounted for a high proportion of

neonates receiving postpartum support [4]

Gelfand et al presented risk factors for

meconium aspiration in infants including

hypertension, gestational diabetes,

preeclampsia, chronic heart disease [3]

Prematures and low birthweight are risk

factors that increase rate of respiratory

distress after birth We evaluated 139

neonates with respiratory failure and 278

neonates without respiratory failure who

were treated at Department of Pediatrics

The average gestational age of the case

group (34 weeks) was significantly lower

than the control group with 38 weeks

(p < 0.001) The average weight of the

case group (2,057 Gr) was significantly

lower than the control group (2,893 Gr)

(p < 0.001) The rate of respiratory failure

in the low birth weight < 2,500 Gr (65.5%)

in case group was significantly higher than

that in the control group (26%) (p < 0.001)

If neonatal weight is smaller than 2,500 Gr, neonates will have a risk of respiratory failure 5.324 (95%CI; 3.429 - 8.267) Mahoney reported that the rate of respiratory distress

of late preterm was 28.9% and term was 5.3%, the early term infants (35 weeks) risk

of respiratory distress was 9 times compared with term baby (38 - 40 weeks) [6]

Cesarean delivery on maternal request

is also one of neonatal respiratory distress risk factors According to our study, the respiratory distress rate was 42.4% in CS

on maternal request group and was only 1%

in the rest This difference has statistical significance (p < 0.05) This problem was investigated by Ray et al in women with

no indication of labor at 34 - 37 gestation weeks, suggesting that more than 25% of neonates have severe respiratory failure after delivery [7] According to a study by Liu et al (2005), full-term infants undergoing

CS on maternal request increased the risk

of respiratory distress [5] It is an issue for gynecologists to do more research to have more concrete evidence in choosing a safe birth route for both mother and newborn baby Obstetrical-neonatal care co-operation module is important and effective in reducing the rate of respiratory distress and asphyxia

in the delivery room especially in the case

of preterm as well as full-term infants whose mothers have chronically diseases, contributes to restrict postpartum morbidity, particularly in cases of respiratory failure, preterm infants In our study, pediatric resuscitation during childbirth was essential for children with respiratory failure at birth (64.7%), while 30.9% of children in the control group needed support of the pediatric resuscitation Pediatric patients, who did

not have any risk, needed for coordination

of pediatric resuscitation (OR = 0.244;

95%CI: 0.158 - 0.375; p < 0.001) This

combination is highly appreciated in the

world and is being implemented in obstetrics

and pediatrics hospitals It is especially

valuable in general hospitals because of

the proportion of mothers with medical

conditions that need to be intervened had

increased more and more, it is necessary

to have other support from the fields of

internal medicine, cardiology combined

with obstetrics and pediatrics to treat both

mother and child properly

The Apgar score provides an accepted

and convenient method for reporting the

status of the newborn infant immediately

after birth and the response to resuscitation

if needed According to our observation,

Apgar score  7 at the first minute at risk

for respiratory distress was OR = 17.888

(95%CI; 10.592 - 29.875; p < 0.001) Thus,

neonatal resuscitation after birth will have

reduced the rate of neonatal respiratory

distress Pediatric and obstetrics combination

actually plays an important role in reducing

the risk of neonatal respiratory distress

CONCLUSION

- The mortality rate from respiratory

failure is high: 15.1% of neonates with

respiratory failure

- Common causes of neonatal respiratory

failure are causes of lung or pulmonary

diseases such as asphyxia, hyaline

membrane disease, pneumonia, transient

tachypnoea of the newborn baby ,

congenital heart defects such as patent

ductus arteriosus, pulmonary arterial

hypertension and respiratory failure in

premature birth, all of them can be intervened

- There are many factors that influence the rate of neonatal respiratory failure related

to maternal pregnancy, maternal morbidity during labor, CS without labour, effective postpartum resuscitation and premature labor, low weight These factors can be intervened to reduce the rate of respiratory failure, asphyxia when pregnancy is managed strictly, proper diagnosis and treatment of maternal disease, holding on relationship between Department of Obstetrics and Department of Pediatrics in caring for

neonates after birth

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