Assessment of the clinical condition and prediction of outcomes in newborns from the neonatal near miss group using the CАSPn, TRIPS and CRIB scales

Introduction

It is difficult to objectively assess the severity of the condition of a newborn child not only due to the anatomical and physiological characteristics of children at different gestational ages and the existence of their “borderline” conditions but also due to the various compensatory capabilities of patients during the early adaptation period.

Existing neonatal scales are an effective tool for assessing the severity of the condition of newborns in resuscitation and intensive care units. The choice of a scale that can be used as a basis for a detailed assessment of the severity and stability of the newborn condition is determined by the possibility of its use under real clinical conditions.

In order to objectively assess the severity of the condition of premature infants, Bushtyrev et al. developed the “Clinical Assessment Scale of Premature Newborn” (CASPN) in 2005 [1]. The authors stated that CASPN allowed for the assessment of the condition of both premature and full-term newborns [2]. The scale is based on screening tests, which evaluate the functional activity of the central nervous, respiratory, cardiovascular, and urinary systems, the condition of the liver and skin integument, as well as body temperature. The severity of each system is assessed from 0 to 2 points. According to the CASPN, transportation to a hospital with a higher level of medical care is possible only if the general condition of the child corresponds to no more than 8 points. With a total score of 9 to 14 points, the risk of death increases, and transportation is contraindicated. The results of a number of studies showed that an objective assessment of the severity of the condition in newborns according to the CASPN made it possible to reduce the mortality rate in the group of transported children from 8.3% in 2013 to 3.0% in 2015 [3–6].

A cohort study was conducted between 2017 and 2018 to examine hospital outcomes in newborns. Before transport, all newborns were assessed using the CASPN. The results showed that as the CASPN score elevated, the number of infants requiring high-frequency mechanical ventilation, dopamine, and epinephrine infusion increased [7].

The Transport Risk Index of Physiologic Stability (TRIPS) for Newborn Infants developed by Lee et al. in 2001 (Vancouver, British Columbia, Canada) is used to assess the severity and stability of the condition of newborns before transportation. The scale can be used to identify newborns with a high risk of mortality. The scale includes an assessment of body temperature, respiratory system, systolic blood pressure, and response to harmful stimuli. The overall TRIPS score is the sum of the points for the 4 parameters listed above. The minimum score is 0 points, the maximum is 65 points. The higher the TRIPS score, the higher the risk of a fatal outcome during the transportation of a newborn [5][6][8–13].

The Clinical Risk Index (CRIB) For Babies was first published in the July 1993 issue of The Lancet. Cockburn et al. developed a system for assessing the condition of newborns immediately after birth for 12 hours. The CRIB scale assesses: birth weight, gestational age, the presence/absence of congenital malformations, base deficit/excess, and maximum and minimum oxygen dependence. When entering data into the CRIB scale, only the gas homeostasis indicator BE-ecf (base deficit/excess – extracellular fluid) can be omitted, and in such case, according to the CRIB instructions, it can be taken as normal. The maximum score is 23 points, the minimum score is 0 points. As the CRIB score elevates, the risk of death increases. This scale was developed thirty years ago, before the widespread use of surfactant and antenatal corticosteroids, when mortality among premature infants with very low birth weight and extremely low birth weight was much higher. According to the instructions for the scale, CRIB (developed in the UK and used mainly in Europe) is applicable to infants with very low birth weight (<1500 g) [13][14].

It is important to remember that the severity of the child’s condition is an inconstant indicator and requires dynamic assessment. Thus, the assessment scale will make it possible to objectify the data on the condition of the newborn at the time of admission to the intensive care unit and in dynamics, against the background of the therapy.

The aim of the study was to conduct a comparative analysis of neonatal scales used to assess the severity of the condition and predict outcomes in newborns.

Materials and methods

The prospective cohort study included 70 newborns born as a result of both singleton and multiple pregnancies and receiving therapy in the Department of Resuscitation and Intensive Care of the Federal State Budgetary Institution “Research Institute of Maternal and Child Health” in the period from 2021 to 2022. Depending on the gestational age (GA), 3 groups were formed: Group I consisted of newborns of GA 23–29.6 weeks (n=24); Group II included children of GA 30–36.6 weeks (n=29), and Group III included full-term newborns of GA 37–40 weeks (n=17). Inclusion criteria for the study were severe birth asphyxia, respiratory distress syndrome, intrauterine infection, and prematurity. Exclusion criteria: fetal growth restriction syndrome, twin-to-twin transfusion syndrome, congenital malformations of the central nervous system, and hereditary metabolic diseases.

The condition of newborns was assessed during the first day of life using three scales: CRIB, TRIPS, and CASPN.

The study was approved by the Ethics Committee of the Ural Research Institute for Maternal and Child Health (protocol No. 12 dated September 21, 2020).

In accordance with the groups of newborns, we conducted an analysis of the exchange cards and birth histories of mothers giving birth to children who have experienced critical conditions in the early neonatal period.

Analysis of the structure of extragenital pathology revealed that women had disorders of the endocrine system. Obesity was recorded in groups I, II, and III in 25%, 24%, and 23.5% of cases, diabetes mellitus was revealed in 8.3%, 3.4%, and 11.8% of cases in groups I, II, and III, respectively. Anemia of varying severity was diagnosed in 45%, 34%, and 35% of cases in groups I, II, and III, respectively, thrombocytopenia was recorded in 13.8%, and 5.9% in groups I and III, chronic arterial hypertension in anamnesis was in 25%, 17.2%, and 5.9% of women in groups I, II, and III, respectively.

Assessment of the obstetric and gynecological anamnesis revealed that the course of the current pregnancy in women in all the examined groups was complicated by acute respiratory viral infection (8.3%; 13.8%; 17.6% in groups I, II, and III, respectively; further, the group order is maintained), confirmed coronavirus infection (33%; 38%; 35.3%), development of chronic fetoplacental insufficiency (46%; 45%; 35.3%), impaired uteroplacental blood flow (41.7%; 31%; 17.6%), premature detachment of a normally located placenta (from 5.9% to 16.7%), gestational diabetes mellitus (30%; 39.1%; 52.9%), and chorioamnionitis (23.3%; 0%; 5.9%), which was significantly more common in women of group I (p_1.2<0.05) and was one of the main indications for emergency delivery of women in group I at a gestation period of less than 30 weeks. The number of operative deliveries in the groups did not differ significantly.

For statistical analysis, the software package Microsoft Excel (2010) and SPSS Statistics version 22.0 (IBM Microsoft, USA) were used. To describe quantitative data, the mean value and standard deviation were used. To describe qualitative parameters, shares and percentages were calculated. The results were considered statistically significant at a significance level of p<0.05.

Results

The clinical characteristics of the studied groups are presented in Table 1.

All the examined newborns differed in GA and body weight. The weight of newborns in groups II and III was comparable. The Apgar scores at the 1st and 5th minutes of life also did not differ in the groups.

All newborns underwent an assessment of gas homeostasis and general and biochemical blood tests during the first day of life.

Decompensated respiratory-metabolic acidosis characterized by a decrease in pH and an increase in the partial pressure of carbon dioxide (pCO₂, mm Hg) and base deficit (BE-ecf, mmol/l) were detected in 33.3% of cases in group I, in 34.5% of newborns in group II, and in 76.5% of children in group III (p_1.3<0.05) (Table 2).

An increase in lactate levels above 4.5 mmol/l was recorded in 45.8% of cases in group I, in 34.5% of children in group II, and in 76.5% of newborns in group III (p_{1.2; 2.3}<0.05).

In group III, decompensated metabolic and lactic acidosis were a consequence of severe asphyxia experienced at birth.

According to the results of a general blood test, 47% of newborns in group I were found to have leukopenia (<5.0×10⁹/l) on the first day of life (Table 3).

In group II, leukopenia was not recorded on the first day of life. In group III, a decrease in leukocytes to less than 5.0×10⁹/l was revealed in 5.9% of children. Anemia (Hb<145 g/l; erythrocytes <4.0×10¹²/l; hematocrit less than 45%) [15] was recorded in group I in 29.2% of newborns and in group II in 17.2% of cases. In newborns from group III, cases of anemia on the first day were not detected (p_1.3<0.05).

One of the main reasons for the development of anemia in the first weeks of life was phlebotomy losses during blood sampling for tests in premature infants of group I due to low body weight, and in children of group II it was related to hemolytic disease of the fetus and newborn.

Thrombocytopenia characterized by a decrease in the level of platelets in the peripheral blood to less than 150×10⁹/l was revealed in all groups: in group I in 29.2% of cases, in group II in 13.4% of patients, and in group III in 29.4% of newborns.

According to the biochemical blood test data on the first day of life, hypoproteinemia (<45 g/l) (p_{1.2; 1.3; 2.3}<0.05) was recorded in 96.7% of cases in newborns from group I, which was associated with immaturity and prematurity, as well as a decrease in the glucose level (<2.6 mmol/l) in 56.7% of newborns. An increase in C-reactive protein (CRP>10 mg/l), which is related to proteins of an acute phase, was found in 33.3% (Table 4).

In groups II and III, hypoproteinemia was detected in 42% and 0% of children, hypoglycemia (<2.6 mmol/l) was determined in 83% and 17.6% of newborns, and an increase in the CRP level was detected in 8.3% and 11.8% of cases, respectively.

Taking into account the severe respiratory failure in extremely premature newborns of group I, traditional artificial ventilation of the lungs (ALV) was performed in 46.6% of cases, and high-frequency oscillatory ventilation of the lungs (HFOV) was performed in the same percentage of children.

In group II, 78.3% of newborns were transferred to ALV from birth time, in 13% of cases children required HFOV and 8.7% of patients received continuous positive airway pressure respiratory therapy.

In Group III, ALV was recorded in 82.3% of cases, and HFOV was performed in 11.8% of cases. The cause of respiratory failure in 58.8% of full-term newborns was severe asphyxia experienced at birth, which in 41.2% of cases required therapeutic hypothermia, according to the Clinical Guidelines “Therapeutic Hypothermia in Newborns” (2019). In other cases, the reason for transferring children to ALV was respiratory failure against the background of congenital pneumonia.

In children of group I, intrauterine infection (IUI) and congenital pneumonia prevailed in 86.6% and 83.3% of cases (p_1.2<0.05; p_1.3<0.05). In group II, these pathologies were observed in 21.7% of newborns. Among full-term newborns of group III, the diagnosis of IUI was recorded in 23.5% of children, and congenital pneumonia was revealed in 35.3% of cases. Every fifth child (20.1%) from group I was diagnosed with cytomegalovirus infection at birth. Complications from the central nervous system (CNS), established by the results of neurosonography, such as intraventricular hemorrhage (IVH grades 2 and 3; 83.3%) and hypoxic-ischemic disorder of the CNS (96.7%), prevailed among children of group I. In addition to the deep morphofunctional immaturity of the brain characterized by weak expression of grooves and convolutions, widening of the interhemispheric fissure, increased bone-marrow diastasis, and dilated vascular plexuses, one more reason for the development of IVH in newborns from group I was severe asphyxia experienced at birth.

Taking into account the severity of the condition and unstable hemodynamics, all newborns underwent echocardiography on the 1st–3rd day of life. According to the ultrasound examination of the heart, patent ductus arteriosus was detected in newborns of groups I, II, and III in 15.4%, 8%, and 36% of cases. Myocardial ischemia and decreased myocardial contractility were registered in 7.7% and 31% of children in group I; arch hypoplasia and preductal coarctation of the aorta were detected in 9% of newborns in group III. No pathologies were detected in children of group II.

In Group I, 95% of newborns received a 4% dopamine infusion, of which 56.5% of children required a combination of dopamine and dobutamine. In Group II, inotropic therapy with dopamine was performed in 90% of cases, of which only 3.4% of patients received a combination of dopamine and dobutamine due to persistent arterial hypotension. In Group III, inotropic support was performed in 64.7% of cases, dobutamine administration was not required.

Based on the results of the assessment of newborns using the CASPN, we revealed that in Group I, in 45.8% of cases, the condition of children who scored the highest number of points was assessed as extremely severe and unstable (Table 5).

The mortality rate in this cohort of children was 36.3%. In Group II, extremely severe unstable conditions were recorded in 17.2% of cases. No fatal outcomes were detected in this subgroup.

In Group III, there was one fatal case in a newborn with a congenital malformation of the lungs, whose condition was assessed at 4 points on the CASPN as severe, but stable at the time of assessment.

According to the Transport Index of Physiological Stability (TRIPS) scale, the maximum number of points (more than 46) was scored by premature infants from Group I, whose condition was assessed as extremely severe and unstable; however, no fatal outcomes were identified in this subgroup (Table 6).

In the subgroup of newborns of group 1 who scored 16–30 points, the mortality rate was 42.3%. In 40% of cases, fatal outcomes were recorded in the subgroup of newborns with 31–45 points. In the group of full-term newborns, a fatal outcome was detected in the subgroup with 16–30 points, where the child scored 20 points out of the maximum 65.

According to the Clinical Risk Index For Babies (CRIB), a fatal outcome was detected in 66.7% of cases in group I among newborns with 7–9 points, while in group III among newborns with a CRIB score of 4–6 points (Table 7).

Mortality in the cohort of children in Group I with the maximum number of points (10–14 points) was 40%. More than 80% of newborns in Group II scored the minimum number of points on the CRIB scale.

Discussion

The scale by Bushtyrev demonstrated the possibility of predicting the development of an unfavorable outcome in newborns of group I, where the higher the score, the higher the risk of fatal outcomes. However, the results of the assessment of the clinical condition of newborns indicated that the condition of a full-term child from group III was underestimated according to the CASPN, since the parameters of the scale did not include indicators of gas homeostasis and acid-base status, which would allow assessing the degree of decompensation of the condition of a newborn with a congenital malformation of the lungs.

In comparison with the CASPN, the TRIPS scale was the most convenient for assessing the condition of newborns, since it made it possible to provide the most detailed picture of the severity and stability of the patient’s condition with the smallest number of indicators. However, according to the TRIPS results, fatal outcomes were recorded in subgroups with average values of points that could also indicate that the available parameters were insufficient to predict adverse outcomes.

Considering the fact that CRIB was initially developed for newborns weighing less than 1500 g, its use in the group of full-term newborns was inappropriate, since in addition to data on the presence of congenital malformations, FiO₂, and the results of acid-base balance, the scale implied an assessment of body weight and GA. Therefore, the lower the GA and body weight, the higher the score on the CRIB scale.

The scales that exist today are the most convenient for assessing the condition of premature newborns and do not make it possible to assess to the full extent the clinical picture and severity of the condition of a full-term child.

Conclusion

Currently, the task of creating a universal scale for not only assessing the severity and stability of the condition of newborns but also for predicting adverse outcomes remains relevant.

It is important that the scale, being accessible and easy to use, would offer the opportunity to operate with the maximum amount of data, which will give all the necessary information to resuscitation specialists and neonatologists providing care to newborns in critical condition.