PRISM score and factors predicting mortality of patients with respiratory failure in the pediatric intensive care unit.

A total of 96 patients with respiratory failure who required mechanical ventilation admitted to the PICU, Chulalongkorn Hospital from July 1998 to June 1999 were reviewed to evaluate the PRISM score for mortality prediction and to identify factors that might influence the outcome. The statistical difference in outcome between the 2 groups (survivors and non-survivors) were underlying diseases, age, maximum positive inspiratory pressure (PIP), maximum positive end expiratory pressure (PEEP), maximum fractional inspiratory oxygen (FiO2) and PRISM score (p < 0.05). However, based on the original logistic regression equation, the predicted mortality from PRISM score in our study was much lower than our actual mortality (2.4% vs 26.0%). The sensitivity and specificity of mortality predicted by PRISM score calculated at cut-off r = 0.0 (expected mortality = 50%) was 4 per cent and 97 per cent respectively. In conclusion, the original PRISM score underpredicted the mortality outcome in our patients with respiratory failure. This suggests that PRISM score is population dependent and should be modified before being used with our patients.

Clinical score and arterial oxygen saturation in children with wheezing associated respiratory illness (WARI).

OBJECTIVES: To determine the correlation between clinical score (based on respiratory rate, chest wall retractions, air entry, wheezing, consciousness and audible wheezing) and arterial oxygen saturation (SaO2: measured by pulse oximetry) as well as the most appropriate total score for predicting hypoxemia (SaO2 < or = 95%) in children diagnosed to have wheezing associated respiratory illness (WARI). SUBJECTS: 70 children (1 month-5 years old) hospitalized in the Department of Pediatrics, Chulalongkorn Hospital with the diagnosis of WARI from January 1, 1996 to December 31, 1996 were studied. Half of them were diagnosed to have acute lower respiratory tract infection (LRI) with wheezing while the remainder had reactive airway disease (RAD). DESIGN: Cross sectional, analytical study. METHODS: In each group of patients, the clinical score and SaO2 were assessed by the same pediatrician throughout the study. The correlation between the clinical signs and SaO2 as well as the cut off point of total score for predicting hypoxemia were analyzed. The sensitivity, specificity and accuracy of that total score in predicting hypoxemia were also calculated. RESULT: In both groups of patients (acute LRI with wheezing and RAD group), the clinical signs correlated with SaO2 were wheezing (rs = -0.67 and -0.47 respectively) and chest wall retractions (rs = -0.57 and -0.59 respectively). Total score was also correlated with SaO2 (rs = -0.68 and -0.5 respectively). The cut off point of total score in predicting hypoxemia was 4 providing 80 per cent sensitivity in both groups with accuracy 74.3 per cent and 80 per cent respectively. CONCLUSION: This clinical score may be used to assess the severity of hypoxemia in WARI patients. Wheezing, chest wall retractions and total score correlated well with SaO2. The total score > 4 was most appropriate in predicting hypoxemia in both children with RAD and wheezing associated with LRI.

Predictors of bronchodilator responsiveness in infants with wheezing associated respiratory tract infection.

The responsiveness to bronchodilator is variable in infants with wheezing associated respiratory illness (WARI). Factors for prediction of the response will lead to more rational use of the bronchodilator in these infants. We examined the possible predictive factors in 44 children under 2 years of age who had their first episode of WARI. All of them were treated with 0.15 mg/kg of nebulized salbutamol. Thirty patients (68%) with decreasing clinical score > or = 3 after treatment were considered as the responders while the remainder (14 infants) were non responders. By using Chi-square test, Fisher exact test and Mann-Whitney U test to compare the data of the 2 groups, the significant factors for the responders were older than 6 months and history of previous LRI (p < 0.01). The significant factors for the non-responders included concurrent diarrhea, patchy pulmonary infiltration and positive RSV in the nasopharyngeal secretion (p < 0.01). These results suggested effective bronchodilator therapy in infants older than 6 months or having a history of previous LRI. Those who had acute RSV infection or patchy infiltration in chest X-ray and associated diarrhea were less likely to respond.