# Evaluation of the classifications of severity in acute respiratory distress syndrome in childhood by the Berlin Consensus and the Pediatric Acute Lung Injury Consensus Conference

## TL;DR

This study compares two classification systems for pediatric acute respiratory distress syndrome and finds strong agreement overall, but neuromuscular blockers affect severity classifications.

## Contribution

The study evaluates the impact of bronchospasm and neuromuscular blockers on the agreement between two severity classifications for pediatric acute respiratory distress syndrome.

## Key findings

- Strong correlation and agreement were found between the Berlin and Pediatric Acute Lung Injury Consensus Conference classifications in the general population.
- Neuromuscular blockers significantly affected both classifications, reducing agreement between them.
- Patients not using neuromuscular blockers showed greater agreement between the two classifications.

## Abstract

To compare two methods for defining and classifying the severity of pediatric acute respiratory distress syndrome: the Berlin classification, which uses the relationship between the partial pressure of oxygen and the fraction of inspired oxygen, and the classification of the Pediatric Acute Lung Injury Consensus Conference, which uses the oxygenation index.

This was a prospective study of patients aged 0 - 18 years with a diagnosis of acute respiratory distress syndrome who were invasively mechanically ventilated and provided one to three arterial blood gas samples, totaling 140 valid measurements. These measures were evaluated for correlation using the Spearman test and agreement using the kappa coefficient between the two classifications, initially using the general population of the study and then subdividing it into patients with and without bronchospasm and those with and without the use of neuromuscular blockers. The effect of these two factors (bronchospasm and neuromuscular blocking agent) separately and together on both classifications was also assessed using two-way analysis of variance.

In the general population, who were 54 patients aged 0 - 18 years a strong negative correlation was found by Spearman’s test (ρ -0.91; p < 0.001), and strong agreement was found by the kappa coefficient (0.62; p < 0.001) in the comparison between Berlin and Pediatric Acute Lung Injury Consensus Conference. In the populations with and without bronchospasm and who did and did not use neuromuscular blockers, the correlation coefficients were similar to those of the general population, though among patients not using neuromuscular blockers, there was greater agreement between the classifications than for patients using neuromuscular blockers (kappa 0.67 versus 0.56, p < 0.001 for both). Neuromuscular blockers had a significant effect on the relationship between the partial pressure of oxygen and the fraction of inspired oxygen (analysis of variance; F: 12.9; p < 0.001) and the oxygenation index (analysis of variance; F: 8.3; p = 0.004).

There was a strong correlation and agreement between the two classifications in the general population and in the subgroups studied. Use of neuromuscular blockers had a significant effect on the severity of acute respiratory distress syndrome.

Comparar dois métodos para definição e classificação de gravidade na síndrome do desconforto respiratório agudo pediátrica: a classificação de Berlim, que utiliza a relação entre pressão parcial de oxigênio e fração inspirada de oxigênio e a classificação do Pediatric Acute Lung Injury Consensus Conference, que utiliza o índice de oxigenação.

Estudo prospectivo com pacientes de 0 - 18 anos com diagnóstico de síndrome do desconforto respiratório agudo e ventilados mecanicamente de forma invasiva, que forneceram de uma a três amostras de gasometria arterial, totalizando 140 medidas válidas. Essas medidas foram avaliadas quanto à correlação pelo teste de Spearman e à concordância pelo coeficiente kappa entre as duas classificações, inicialmente usando a população geral do estudo e, depois, subdividindo-a em pacientes com e sem broncoespasmo e com e sem o uso do bloqueador neuromuscular. Também foi verificado o efeito desses dois fatores (broncoespasmo e bloqueador neuromuscular) de forma separada e conjunta sobre ambas as classificações por meio da análise de variância para dois fatores.

Na população geral, composta de 54 pacientes com idades de 0 - 18 anos, foi encontrada forte correlação negativa pelo teste de Spearman (ρ -0,91; p < 0,001) e forte concordância pelo coeficiente kappa (0,62; p < 0,001) na comparação entre Berlim e Pediatric Acute Lung Injury Consensus Conference. Nas populações com e sem broncoespasmo e com e sem o uso do bloqueador neuromuscular, os coeficientes de correlação mantiveram valores semelhantes aos da população geral. Entretanto, para os pacientes sem uso do bloqueador neuromuscular, houve maior concordância entre as classificações em relação aos pacientes com uso do bloqueador neuromuscular (kappa 0,67 versus 0,56 com p < 0,001 em ambos). Acrescenta-se ainda o efeito significativo do uso do bloqueador neuromuscular sobre a relação entre pressão parcial de oxigênio e fração inspirada de oxigênio (análise de variância; F: 12,9; p < 0,001) e o índice de oxigenação (análise de variância; F: 8,3; p = 0,004).

Houve forte correlação e concordância entre as duas classificações na população geral e nos subgrupos estudados, entretanto, há efeito significativo do uso do bloqueador neuromuscular sobre as classificações de gravidade da síndrome do desconforto respiratório agudo.