Use of extubation bundle including modified spontaneous breathing trial (SBT) to reduce the rate of reintubation,among preterm neonates ≤ 30 weeks

Abstract

BACKGROUND:

Respiratory support in the form of mechanical ventilation is a crucial intervention in premature neonates, with respiratory problems. However, prolonged mechanical ventilation and endotracheal intubation may be associated with major adverse effects. The ideal time for extubation is based on clinical and laboratory parameters assessed at the time of planned extubation. However, such parameters are not very objective, which makes extubation in NICUs a trial-and-error approach.

OBJECTIVE:

This work was done to assess the use of extubation bundle including modified spontaneous breathing trial (SBT) (10 minutes) to reduce the rate of reintubation, among preterm neonates≤30 weeks who were mechanically ventilated and extubated to non-invasive ventilation in the NICU, Women’s Wellness and Research Center (WWRC), Hamad Medical Corporation (HMC), Doha, Qatar.

METHODS:

A prospective study based on the collection of data regarding preterm neonates≤30 weeks gestation admitted to the NICU, Women’s Wellness and Research Center (WWRC), from January, 2015 to December, 2017, who were subjected to mechanical ventilation (MV) and extubation. When the clinical team decides a newborn is ready for extubation based on the extubation bundle, a modified SBT (10 min) is used.

RESULTS:

This study included 465 premature babies from 24-≤30 weeks recruited in the NICU, Women’s Wellness and Research Center (WWRC). Extubation bundle with modified SBT was able to predict success of extubation with 95% sensitivity and 90.4% Positive Predictive Value (PPV) in the gestational age (GA) group 24 -≤27 weeks (245) and 95.3% sensitivity and 90% PPV in the GA group > 27 -≤30 weeks (220). As expected, successfully extubated babies had a higher GA and weighed more at extubation, compared to babies who required re-intubation.

CONCLUSION:

We recommend the extubation bundle with modified SBT prior to elective extubation to be used in predicting successful extubation in premature babies. Guidelines for extubation among premature babies are needed in order to reduce unnecessary exposure to adverse effects of mechanical ventilation.

1 Introduction

Respiratory support in the form of mechanical ventilation is a crucial intervention in premature neonates, with respiratory problems. However, prolonged mechanical ventilation and endotracheal intubation may be associated with major adverse effects, such as ventilation-associated pneumonia (VAP), pneumothorax, bronchopulmonary dysplasia (BPD) and periventricular hemorrhage [1, 2].

To minimize such risks and complications, it is recommended to discontinue MV as soon as babies are able to maintain spontaneous breathing and achieve appropriate gas exchange with minimal respiratory effort [2]. The ideal time for extubation is based on clinical and laboratory parameters assessed at the time of planned extubation. However, such parameters are not very objective, which makes extubation in NICUs a trial-and-error approach [2, 3]. Based on the morbidities associated with the long duration of MV in newborn babies, there is a clear need to establish objective criteria for extubation and avoid reintubation [3 –7]. The aim of this work is assess the use of extubation bundle including modified SBT (10 minutes) to reduce the rate of reintubation, among preterm neonates≤30 weeks who were mechanically ventilated and extubated to non-invasive ventilation in NICU, Women’s Wellness and Research Center (WWRC), Hamad Medical Corporation (HMC), Doha, Qatar. In our NICU, the data prior to this work showed up to 30% of mechanically ventilated preterm neonates≤30 weeks gestation at birth requires reintubation following extubation. Failure of extubation has been associated with higher morbidity and mortality, increased length of hospital stay and more ventilator days [8]. Thus, identifying techniques for predicting successful extubation attempts may reduce mortality and morbidity associated with ill-timed extubation attempts. Adequate brain maturity and lung function are prerequisites for successful transition from mechanical ventilation to spontaneous breathing among premature babies. In the absence of significant apneic episodes, bedside pulmonary function tests may be useful in conjunction with infant’s clinical status and blood gas parameters to predict the success of extubation [9, 10]. Data on pulmonary function tests prior to extubation in premature babies are limited and conflicting. Most of the studies were conducted in babies with wide ranges of GA, birth weight, and postnatal age at extubation and did not account for comorbidities such as patent ductus arteriosus (PDA), pulmonary hemorrhage, severe intracranial hemorrhage, atelectasis, and pneumonia after extubation that may contribute to the failure of extubation [9 –12]. In this study, our objective was to evaluate the validity of extubation bundle including modified SBT in predicting successful extubation in premature neonates with planned extubation. We hypothesized that extubation bundle including modified SBT prior to extubation can independently predict successful extubation in preterm babies≤30 weeks gestation.

2 Subjects and methods

This study was a prospective study based on the collection of data regarding preterm neonates≤30 weeks gestation admitted to the NICU, Women’s Wellness and Research Center (WWRC), from January 2015 to December 2017, who were subjected to mechanical ventilation (MV) and extubation. When the clinical team decides a newborn is ready for extubation based on the extubation bundle, a modified SBT (10 min) is used; the provider compliance rate with the extubation bundle was 95% [Fig. 1] This study is a quality project conducted in NICU after approval by the Hospital Research Committee, to minimize extubation failure. A general consent was obtained on admission of all studied cases regarding respiratory management including extubation bundle. Patients were admitted under their health card (HC) number and not by name. NICU, Women’s Wellness and Research Center (WWRC), is a tertiary level care unit with 110 beds (Tiny baby unit, intensive care unit & intermediate care). Total number of deliveries in the Hospital for the years 2015, 2016 and 2017 was 15063, 16170 and 16768 respectively. Plan, Do, Study, Act (PDSA) cycle according to International Health Institiute (IHI) was the process used in this quality project. Newborn babies≤30 weeks of both genders born at Women and Wellness and Research Center (WWRC), and subjected to mechanical ventilation and extubation during the data collection period were included in the study. Candidates of the study were sub-classified into two subgroups based on GA, group 1 included 245 babies with GA ranging from 24 weeks -≤27 weeks and group 2 included 220 babies with GA ranging from > 27 weeks to≤30 weeks. Mechanical ventilation was performed using Dragger VN 5000 and SLE 5000 ventilators. The babies’ GA was established by means of ultrasound or the date of the mother’s last menstrual period (LMP) and new Ballard maturational score. Assessment included the occurrence of extubation failure in addition to clinical and treatment-related variables. Extubation was considered successful when the babies were able to remain without invasive ventilatory support for 24 hours; extubation failure was defined as the need for reintubation for any reason within 24 hours after extubation. Accidental extubation followed by immediate reintubation and the use of invasive ventilatory support were not considered as extubation failure. The time for extubation was determined by the medical staff based on clinical assessment and locally designed extubation bundle (Table 1). A modified SBT was performed when ventilated babies are ready for extubation, if failed SBT to be repeated until successful. The data were recorded using NICU, Women’s Wellness and Research Center (WWRC) standard charts. The variables analyzed included the following: mode of delivery, GA, birth weight, gender, antenatal corticosteroids, surfactant, date of intubation and extubation, length of mechanical ventilation (days), extubation failure and reintubation. Babies were divided into two groups based upon whether they failed or passed the extubation attempt. The primary outcome is failed extubation (reintubation within 24 hours). The indications for reintubation were specified: (a) more than one episode of significant apnea requiring intervention in 8 hours, (b) Respiratory acidosis (PaCO2 more than 65 mm Hg and pH less than 7.25); (c) FiO2.0.60 to maintain SpO2 in the target range (90–95%). The secondary outcome is determining the value of the modified SBT in extubation success. Descriptive statistics was used to show the distribution of variables using numbers and percentages or means and standard deviation (SD) as applicable. Continuous variables were compared using Student’s t-test while categorical variables were compared using Chi-squared test. Sensitivity, Specificity, Positive Predictive Value, Negative Predictive Value and Diagnostic Accuracy were calculated for both the 24 weeks -≤27 weeks weeks and > 27 weeks to≤30 weeks groups. Statistical analysis was performed using excel and OpenEpi, Version 3, open source calculator. Statistical significance was set at p < 0.05.

Fig.1

Extubation bundle.

Table 1

Extubation bundle elements

Discuss readiness for extubation	Baby triggering well (Adequate respiratory drive)		Mean airway pressure <9 cm H₂O	FiO₂ < 30%	VT<5 ml/kg	Modified SBT Done
	Caffeine citrate	Weaned from Sedation

3 Results

Baseline characteristics for the two groups were compared using chi-square test for categorical variables, while T-test was used for continuous variables based on the distribution. Table 2 shows that there is no statistically significant differences in GA, birth weight,, gender, mode of delivery, use of antenatal steroids, Apgar scores, age at extubation, and use of caffeine therapy between babies who failed and those who were successfully extubated, but there is a statistically significant difference between both groups regarding surfactant doses administered.

Table 2
Demographic data for preterm babies from 24 weeks – ≤27 weeks (n = 245)

Clinical variable Success group (n = 159) Failure group (n = 86) P-value

Gestation (weeks) 26.4±0.7 25.6±0.6 0.1162^‡

Birth weight (gm) 790±60 740±55 0.3760^‡

Gender (M/F) 75 / 84 36/50 0.4256^†

Mode of delivery (VD/CS) 85 /74 47 /39 0.8582^†

Antenatal steroids (Yes/No) 96 / 63 50 /36 0.7333^†

Apgar score 7±1 6±1 1.01^‡

Surfactant doses (Yes/No) 150/9 72/14 0.00653

Age at extubation (days) 10.1±1.3 6.8±1.5 0.1236^‡

Caffeine citrate 159 (100%) 86 (100%) NA

Clinical variable	Success group (n = 159)	Failure group (n = 86)	P-value
Gestation (weeks)	26.4±0.7	25.6±0.6	0.1162^‡
Birth weight (gm)	790±60	740±55	0.3760^‡
Gender (M/F)	75 / 84	36/50	0.4256^†
Mode of delivery (VD/CS)	85 /74	47 /39	0.8582^†
Antenatal steroids (Yes/No)	96 / 63	50 /36	0.7333^†
Apgar score	7±1	6±1	1.01^‡
Surfactant doses (Yes/No)	150/9	72/14	0.00653
Age at extubation (days)	10.1±1.3	6.8±1.5	0.1236^‡
Caffeine citrate	159 (100%)	86 (100%)	NA

^‡T-test. ^†chi-square test, M: male, F: female, VD: vaginal delivery, CS: Cesarean section.

Table 3 shows that there is no statistically significant differences in GA, mode of delivery, use of antenatal steroids, Apgar scores, age at extubation, surfactant doses administered and use of caffeine therapy between babies who failed and those who were successfully extubated, but there is a statistically significant difference between both groups regarding birth weight (0.00159) and gender (0.02905).

Table 3

Demographic data for preterm babies from > 27 weeks to≤30 weeks (n = 220)

Clinical variable	Success group (n = 170)	Failure group (n = 50)	P-value
Gestation (weeks)	28.6±0.8	27.8±0.9	0.2767^‡
Birth weight (gm)	890±150	820±74	0.00159^‡
Gender (M/F)	93/77	36/14	0.02905^†
Mode of delivery (VD/CS)	94/76	35/15	0.06345^†
Antenatal steroids (Yes/No)	108/62	38/12	0.1009^†
Apgar score	8±1	7±1	1.03^‡
Surfactant doses (Yes/No)	100/70	33/17	0.3616^†
Age at extubation (days)	7.2±1.4	4.6±1.5	0.5161^‡
Caffeine citrate	170 (100%)	50 (100%)	NA

^‡T-test, ^† chi-square test, M: male, F: female, VD: vaginal delivery, CS: Cesarean section.

4 Discussion

This work was done to evaluate the value of the modified SBT as a part of extubation bundle to enhance extubation of preterm babies≤30 weeks. This study included 465 premature babies from 24 -≤30 weeks recruited in the NICU, Women and Wellness and Research Center (WWRC) from January 2015 to December 2017. Extubation bundle with modified SBT was able to predict success of extubation with 95% sensitivity and 90.4% PPV in the GA group 24 -≤27 weeks (245) and 95.3% sensitivity and 90% PPV in the GA group > 27 -≤30 weeks (220) (Tables 4 & 5). As expected, successfully extubated babies had a higher GA and weighed more at extubation, compared to babies who required re-intubation. These results are in agreement with Chawla et al., who applied SBT for up to 5 minutes for preterm babies from 24 to 32 weeks gestation [13]. They demonstrated that SBT performed for elective extubation was able to predict success of extubation with 92% sensitivity and 88% PPV. Also, they demonstrated that multivariate logistic regression analysis with GA as covariate revealed that passing SBT remained an independent predictor of successful extubation. Our data on the value of modified SBT in neonates are comparable to previously reported studies on the SBT in premature babies by Kamlin et al., who found a sensitivity of 97%, and a positive predictive value for extubation success of 93%. In another prospective audit, the same investigators found that VLBW babies (<1,250 gm) were extubated at significantly higher support compared to historic controls [14]. We arbitrarily selected 10 min for duration of modified SBT, because we speculated that a longer duration of SBT (15–120 min) as used among children and adults may precipitate atelectasis and increase the work of breathing in premature babies [15, 16]. Low negative predictive value of modified SBT may be due to increased work of breathing through a small diameter ETT without pressure support, precipitating failure of modified SBT. In Kamlin’s study, SBT was performed for 3 min and most neonates who failed SBT did so in the first 90 sec, compared to 3–5 min in our study, and 3–4 min in Chawla et al. study [13]. Babies in Kamlin’s study were on higher ventilator support prior to elective extubation, compared to those in the current study (MAP of < 7, FIO2 < 30% and TV 4–6 ml/Kg) [14]. In addition, in the study by Kamlin, the mode of ventilation was either assist control or SIMV, in contrast to PC-AC with VG in most of our babies [14]. These differences may explain the difference in the timing of failed SBT in the two studies. Having a shorter time (3 min, 5 min vs. 10 min) for SBT may miss some patients who would fail the trial after 3 and 5 min. Therefore, a 10-min modified SBT may be a reasonable time period to identify extubation-readiness in the majority of babies, whereas failure of 10-min modified SBT may suggest reassessment of clinical condition of the patient, prior to extubation (Table 6).

Table 4

Sensitivity and septicity for modified SBT in predicting successful extubation in preterm babies from 24 – ≤27 weeks (245)

Table 5

Sensitivity and septicity for modified SBT in predicting successful extubation in preterm babies >27 – ≤30 weeks (220)

Table 6

Failed SBT in the two studied groups

	Failure in 3–5 min	Failure in 6–10 min
Preterm babies 24 -≤27 weeks	62	16
Preterm babies > 27 -≤30 weeks	29	11

In our study approximately 95% of the studied groups who passed the modified SBT were not reintubated, compared to babies who failed the modified SBT (5%), in comparison to the results by Chawla et al., who showed that babies who passed the SBT were 6.6 times more likely to be successfully extubated [13]. This difference could be explained by the fact that extended SBT among extubation bundle improved the success rate of extubation. Our extubation failure rate of 5% is much better than previous reported rates of 20–22% in the premature infant population [12, 17]. There were two limitations to the use of extubation bundle with the extended SBT. First, the period of endotracheal intubation could be prolonged if caregivers waited for preterm babies to pass the extended SBT when they might otherwise have decided to extubate earlier. Second, by encouraging extubation sooner than the caregiver might have decided, more preterm babies might have required reintubation. In summary, we recommend the extubation bundle with modified SBT prior to elective extubation to be used in predicting successful extubation in premature babies. Guidelines for extubation among premature babies are needed in order to reduce unnecessary exposure to adverse effects of mechanical ventilation. Further multicenter studies related to extubation guidelines in preterm babies less than 30 weeks are needed to improve the outcome and reduce morbidity and mortality in this age group.

References

Fávero

, Schuster

, Wojahn

, Tartari

. Incidência e principais fatores associados à falha na extubação em recém-nascidos prematuros. Pediatria (São Paulo). 2011;33(1):13–20.

Davidson

, Miyoshi

, Santos

, Carvalho

. Medida da frequência respiratória e do volume corrente para prever a falha na extubação de recém-nascidos de muito baixo peso em ventilação mecânica. Rev Paul Pediatr. 2008;26(1):36–42.

Cruces

, Donoso

, Montero

, López

, Fernández

, Díaz

, et al. Predicción de fracaso de extubación en pacientes pediátricos: Experiencia de dos años en una UCI polivalente. Rev Chil Med Intensiv. 2008;23(1):12–7.

Newth

, Venkataraman

, Willson

, Meert

, Harrison

, Dean

, Pollack

, Zimmerman

, Anand

, Carcillo

, Nicholson

; Eunice Shriver Kennedy National Institute of Child Health and Human Development Collaborative Pediatric Critical Care Research Network. Weaning and extubation readiness in pediatric patients. Pediatr Crit Care Med. 2009;10(1):1–11.

Andrade

, Melo

, Morais

, Lima

, Albuquerque

, Martimiano

. Avaliação do teste de respiração espontânea na extubação de neonatos pré-termo. Rev Bras Ter Intensiva. 2010;22(2):159–65.

Johnston

, Piva

, Carvalho

, Garcia

, Fonseca

, Hommerding

. Preditores de falha da extubação em crianças no pós-operatório de cirurgia cardíaca submetidas à ventilação pulmonar mecânica. Rev Bras Ter Intensiva. 2008;20(1):57–62.

Kurachek

, Newth

, Quasney

, Rice

, Sachdeva

, Patel

, et al. Extubation failure in pediatric intensive care: A multiple-center study of risk factors and outcomes. Crit Care Med. 2003;31(11):2657–64.

Biban

Paolo

, Gaffuri

Marcella

, Spaggiari

Stefania

, Silvagni

Davide

, Zaglia

Federico

, Santuz

Pierantonio

. Weaning newborn infants from mechanical ventilation. JPNIM. 2013;2(2).

Veness-Meehan

, Richter

, Davis

. Pulmonary function testing prior to extubation in infants with respiratory distress syndrome. Pediatr Pulmonol. 1990;9:2–6.

10.

Szymankiewicz

, Vidyasagar

, Gadzinowski

. Predictors of successful extubation of preterm low-birth-weight infants with respiratory distress syndrome. Pediatr Crit Care Med. 2005;6:44–49.

11.

Balsan

, Jones

, Watchko

, Guthrie

. Measurements of pulmonary mechanics prior to the elective extubation of neonates. Pediatr Pulmonol. 1990;9:238–43.

12.

Kamlin

, Davis

, Morley

. Predicting successful extubation of very low birthweight infants. Arch Dis Child Fetal Neonatal Ed. 2006;91:F180–F183.

13.

Chawla

, Matthew

, Nadya

, Kazzi

. Role of spontaneous breathing trial in predicting successful extubation in premature infants. Pediatr Pulmonol. 2013;48:443–48.

14.

Kamlin , Davis

, Argus

, Mills

, Morley

. A trial of spontaneous breathing to determine the readiness for extubation in very low birth weight infants: A prospective evaluation. Arch Dis Child Fetal Neonatal Ed. 2008;93:F305–F306.

15.

Esteban

, Alia

, Gordo

, Fernandez

, Solsona

, Vallverdu

, Macias

, Allegue

, Blanco

, Arriedo

, Leon

, de la Cal

, Taboada

, Gonzalez de Velasco

, Palazon

, Carrizosa

, Tomas

, Suarez

, Goldwasser

. Extubation outcome after spontaneous breathing trials with T-tube or pressure support ventilation. Am J Respir Crit Care Med. 1997;156:459–65.

16.

Chavez

, Cruz

, Zaritsky

. Spontaneous breathing trial predicts successful extubation in infants and children. Pediatr Crit Care Med. 2006;7:324–8.

17.

Dimitriou

, Greenough

, Endo

, Cherian

, Rafferty

. Prediction of extubation failure in preterm infants. Arch Dis Child Fetal Neonatal Ed. 2002;86:F32–F35.