Inflammatory lung injury in rabbits: effects of high-frequency oscillatory ventilation in the prone position.

OBJECTIVE: To compare the effects that prone and supine positioning during high-frequency oscillatory ventilation (HFOV) have on oxygenation and lung inflammation, histological injury, and oxidative stress in a rabbit model of acute lung injury (ALI). METHODS: Thirty male Norfolk white rabbits were induced to ALI by tracheal saline lavage (30 mL/kg, 38°C). The injury was induced during conventional mechanical ventilation, and ALI was considered confirmed when a PaO2/FiO2 ratio < 100 mmHg was reached. Rabbits were randomly divided into two groups: HFOV in the supine position (SP group, n = 15); and HFOV with prone positioning (PP group, n = 15). For HFOV, the mean airway pressure was initially set at 16 cmH2O. At 30, 60, and 90 min after the start of the HFOV protocol, the mean airway pressure was reduced to 14, 12, and 10 cmH2O, respectively. At 120 min, the animals were returned to or remained in the supine position for an extra 30 min. We evaluated oxygenation indices and histological lung injury scores, as well as TNF-α levels in BAL fluid and lung tissue. RESULTS: After ALI induction, all of the animals showed significant hypoxemia, decreased respiratory system compliance, decreased oxygenation, and increased mean airway pressure in comparison with the baseline values. There were no statistically significant differences between the two groups, at any of the time points evaluated, in terms of the PaO2 or oxygenation index. However, TNF-α levels in BAL fluid were significantly lower in the PP group than in the SP group, as were histological lung injury scores. CONCLUSIONS: Prone positioning appears to attenuate inflammatory and histological lung injury during HFOV in rabbits with ALI.

Comparison between conventional protective mechanical ventilation and high-frequency oscillatory ventilation associated with the prone position. / Comparação entre ventilação mecânica convencional protetora e ventilação oscilatória de alta frequência associada à posição prona.

OBJECTIVE: To compare the effects of high-frequency oscillatory ventilation and conventional protective mechanical ventilation associated with the prone position on oxygenation, histology and pulmonary oxidative damage in an experimental model of acute lung injury. METHODS: Forty-five rabbits with tracheostomy and vascular access were underwent mechanical ventilation. Acute lung injury was induced by tracheal infusion of warm saline. Three experimental groups were formed: healthy animals + conventional protective mechanical ventilation, supine position (Control Group; n = 15); animals with acute lung injury + conventional protective mechanical ventilation, prone position (CMVG; n = 15); and animals with acute lung injury + high-frequency oscillatory ventilation, prone position (HFOG; n = 15). Ten minutes after the beginning of the specific ventilation of each group, arterial gasometry was collected, with this timepoint being called time zero, after which the animal was placed in prone position and remained in this position for 4 hours. Oxidative stress was evaluated by the total antioxidant performance assay. Pulmonary tissue injury was determined by histopathological score. The level of significance was 5%. RESULTS: Both groups with acute lung injury showed worsening of oxygenation after induction of injury compared with the Control Group. After 4 hours, there was a significant improvement in oxygenation in the HFOG group compared with CMVG. Analysis of total antioxidant performance in plasma showed greater protection in HFOG. HFOG had a lower histopathological lesion score in lung tissue than CMVG. CONCLUSION: High-frequency oscillatory ventilation, associated with prone position, improves oxygenation and attenuates oxidative damage and histopathological lung injury compared with conventional protective mechanical ventilation.

OBJETIVO: Comparar os efeitos da ventilação oscilatória de alta frequência e da ventilação mecânica convencional protetora associadas à posição prona quanto à oxigenação, à histologia e ao dano oxidativo pulmonar em modelo experimental de lesão pulmonar aguda. MÉTODOS: Foram instrumentados com traqueostomia, acessos vasculares e ventilados mecanicamente 45 coelhos. A lesão pulmonar aguda foi induzida por infusão traqueal de salina aquecida. Foram formados três grupos experimentais: animais sadios + ventilação mecânica convencional protetora, em posição supina (Grupo Controle; n = 15); animais com lesão pulmonar aguda + ventilação mecânica convencional protetora, posição prona (GVMC; n = 15); animais com lesão pulmonar aguda + ventilação oscilatória de alta frequência, posição prona (GVAF; n = 15). Após 10 minutos do início da ventilação específica de cada grupo, foi coletada gasometria arterial, sendo este momento denominado tempo zero, após o qual o animal foi colocado em posição prona, permanecendo assim por 4 horas. O estresse oxidativo foi avaliado pelo método de capacidade antioxidante total. A lesão tecidual pulmonar foi determinada por escore histopatológico. O nível de significância adotado foi de 5%. RESULTADOS: Ambos os grupos com lesão pulmonar aguda apresentaram piora da oxigenação após a indução da lesão comparados ao Grupo Controle. Após 4 horas, houve melhora significante da oxigenação no grupo GVAF comparado ao GVMC. A análise da capacidade antioxidante total no plasma mostrou maior proteção no GVAF. O GVAF apresentou menor escore de lesão histopatológica no tecido pulmonar que o GVMC. CONCLUSÃO: A ventilação oscilatória de alta frequência, associada à posição prona, melhora a oxigenação, e atenua o dano oxidativo e a lesão pulmonar histopatológica, comparada com ventilação mecânica convencional protetora.

Inflammatory lung injury in rabbits: effects of high-frequency oscillatory ventilation in the prone position / Lesão inflamatória pulmonar em coelhos: efeitos da ventilação oscilatória de alta frequência em posição prona

ABSTRACT Objective: To compare the effects that prone and supine positioning during high-frequency oscillatory ventilation (HFOV) have on oxygenation and lung inflammation, histological injury, and oxidative stress in a rabbit model of acute lung injury (ALI). Methods: Thirty male Norfolk white rabbits were induced to ALI by tracheal saline lavage (30 mL/kg, 38°C). The injury was induced during conventional mechanical ventilation, and ALI was considered confirmed when a PaO2/FiO2 ratio < 100 mmHg was reached. Rabbits were randomly divided into two groups: HFOV in the supine position (SP group, n = 15); and HFOV with prone positioning (PP group, n = 15). For HFOV, the mean airway pressure was initially set at 16 cmH2O. At 30, 60, and 90 min after the start of the HFOV protocol, the mean airway pressure was reduced to 14, 12, and 10 cmH2O, respectively. At 120 min, the animals were returned to or remained in the supine position for an extra 30 min. We evaluated oxygenation indices and histological lung injury scores, as well as TNF-α levels in BAL fluid and lung tissue. Results: After ALI induction, all of the animals showed significant hypoxemia, decreased respiratory system compliance, decreased oxygenation, and increased mean airway pressure in comparison with the baseline values. There were no statistically significant differences between the two groups, at any of the time points evaluated, in terms of the PaO2 or oxygenation index. However, TNF-α levels in BAL fluid were significantly lower in the PP group than in the SP group, as were histological lung injury scores. Conclusions: Prone positioning appears to attenuate inflammatory and histological lung injury during HFOV in rabbits with ALI.

RESUMO Objetivo: Comparar os efeitos das posições prona e supina durante ventilação oscilatória de alta frequência (VOAF) sobre oxigenação e inflamação pulmonar, lesão histológica e estresse oxidativo em um modelo de lesão pulmonar aguda (LPA) em coelhos. Métodos: Trinta coelhos Norfolk machos brancos foram submetidos à LPA por meio de lavagem traqueal com salina (30 ml/kg, 38°C). A lesão foi induzida durante a ventilação mecânica convencional, e a LPA foi considerada confirmada na presença de relação PaO2/FiO2 < 100 mmHg. Os coelhos foram aleatoriamente divididos em dois grupos: VOAF em posição supina (grupo PS, n = 15); e VOAF em posição prona (grupo PP, n = 15). Para a VOAF, a pressão média das vias aéreas foi inicialmente estabelecida em 16 cmH2O. No 30º, 60º e 90º min após o início do protocolo de VOAF, a pressão média das vias aéreas foi reduzida para 14, 12 e 10 cmH2O, respectivamente. No 120º min, os animais foram recolocados ou permaneceram na posição supina por mais 30 min. Foram avaliados os índices de oxigenação e escores histológicos de lesão pulmonar, bem como os níveis de TNF-α em lavado broncoalveolar e tecido pulmonar. Resultados: Após a indução da LPA, todos os animais apresentaram hipoxemia significativa, diminuição da complacência do sistema respiratório, diminuição da oxigenação e aumento da pressão média das vias aéreas em comparação aos valores basais. Não houve diferenças estatisticamente significativas entre os dois grupos, em nenhum dos momentos avaliados, quanto a PaO2 e índice de oxigenação. Entretanto, os níveis de TNF-α no lavado broncoalveolar foram significativamente menores no grupo PP que no grupo PS, assim como os escores histológicos de lesão pulmonar. Conclusões: A posição prona parece atenuar a lesão pulmonar inflamatória e histológica durante a VOAF em coelhos com LPA.

Interactive effects of mechanical ventilation, inhaled nitric oxide and oxidative stress in acute lung injury.

To compare conventional mechanical ventilation (CMV) and high-frequency oscillatory ventilation (HFOV), with/without inhaled nitric oxide (iNO), for oxygenation, inflammation, antioxidant/oxidative stress status, and DNA damage in a model of acute lung injury (ALI). Lung injury was induced by tracheal infusion of warm saline. Rabbits were ventilated at [Formula: see text] 1.0 and randomly assigned to one of five groups. Overall antioxidant defense/oxidative stress was assessed by total antioxidant performance assay, and DNA damage by comet assay. Ventilatory and hemodynamic parameters were recorded every 30min for 4h. ALI groups showed worse oxygenation than controls after lung injury. After 4h of mechanical ventilation, HFOV groups presented significant improvements in oxygenation. HFOV with and without iNO, and CMV with iNO showed significantly increased antioxidant defense and reduced DNA damage than CMV without iNO. Inhaled nitric oxide did not beneficially affect HFOV in relation to antioxidant defense/oxidative stress and pulmonary DNA damage. Overall, lung injury was reduced using HFOV or CMV with iNO.

Interleukin-12 in children with sepsis and septic shock. / Interleucina-12 em crianças com sepse e choque séptico.

OBJECTIVE: To examine the behavior of interleukin-12 and verify whether it can be used to differentiate septic conditions in children. METHODS: Septic children aged between 28 days and 14 years, prospectively enrolled from 01/2004 to 12/2005, were divided into sepsis (SG; n=47) and septic shock (SSG; n=43) groups. Interleukin-12 levels were measured at admission (T0) and 12 hours later (T12). Disease severity was assessed by the PRISM score. RESULTS: Interleukin-12 levels did not differentiate children with sepsis from those with septic shock at admission [SSG: 0.24 (0-226.4)=SG: 1.23 (0-511.6); p=0.135)] and T12 [SG: 6.11 (0-230.5)=SSG: 1.32 (0-61.0); p=0.1239)]. Comparing time points, no significant difference was observed in the SG [SG, T0: 1.23 (0-511.6)=T12: 6.11 (0-230.5); p=0.075]. In SSG however, interleukin-12 increased from T0 to T12 (SSG, T0: 0.24 (0-226.4)0.05). There was no correlation between onterleukin-12 levels at admission and the PRISM score for either group. CONCLUSION: Interleukin-12 levels cannot differentiate between septic conditions and are not related to disease severity at admission. In septic shock patients, interleukin-12 increases with time.

Biomarkers for oxidative stress in acute lung injury induced in rabbits submitted to different strategies of mechanical ventilation.

Oxidative damage has been said to play an important role in pulmonary injury, which is associated with the development and progression of acute respiratory distress syndrome (ARDS). We aimed to identify biomarkers to determine the oxidative stress in an animal model of acute lung injury (ALI) using two different strategies of mechanical ventilation. Rabbits were ventilated using either conventional mechanical ventilation (CMV) or high-frequency oscillatory ventilation (HFOV). Lung injury was induced by tracheal saline infusion (30 ml/kg, 38°C). In addition, five healthy rabbits were studied for oxidative stress. Isolated lymphocytes from peripheral blood and lung tissue samples were analyzed by alkaline single cell gel electrophoresis (comet assay) to determine DNA damage. Total antioxidant performance (TAP) assay was applied to measure overall antioxidant performance in plasma and lung tissue. HFOV rabbits had similar results to healthy animals, showing significantly higher antioxidant performance and lower DNA damage compared with CMV in lung tissue and plasma. Total antioxidant performance showed a significant positive correlation (r = 0.58; P = 0.0006) in plasma and lung tissue. In addition, comet assay presented a significant positive correlation (r = 0.66; P = 0.007) between cells recovered from target tissue and peripheral blood. Moreover, antioxidant performance was significantly and negatively correlated with DNA damage (r = -0.50; P = 0.002) in lung tissue. This study indicates that both TAP and comet assay identify increased oxidative stress in CMV rabbits compared with HFOV. Antioxidant performance analyzed by TAP and oxidative DNA damage by comet assay, both in plasma, reflects oxidative stress in the target tissue, which warrants further studies in humans.

Comparação entre ventilação mecânica convencional protetora e ventilação oscilatória de alta frequência associada à posição prona / Comparison between conventional protective mechanical ventilation and high-frequency oscillatory ventilation associated with the prone position

RESUMO Objetivo: Comparar os efeitos da ventilação oscilatória de alta frequência e da ventilação mecânica convencional protetora associadas à posição prona quanto à oxigenação, à histologia e ao dano oxidativo pulmonar em modelo experimental de lesão pulmonar aguda. Métodos: Foram instrumentados com traqueostomia, acessos vasculares e ventilados mecanicamente 45 coelhos. A lesão pulmonar aguda foi induzida por infusão traqueal de salina aquecida. Foram formados três grupos experimentais: animais sadios + ventilação mecânica convencional protetora, em posição supina (Grupo Controle; n = 15); animais com lesão pulmonar aguda + ventilação mecânica convencional protetora, posição prona (GVMC; n = 15); animais com lesão pulmonar aguda + ventilação oscilatória de alta frequência, posição prona (GVAF; n = 15). Após 10 minutos do início da ventilação específica de cada grupo, foi coletada gasometria arterial, sendo este momento denominado tempo zero, após o qual o animal foi colocado em posição prona, permanecendo assim por 4 horas. O estresse oxidativo foi avaliado pelo método de capacidade antioxidante total. A lesão tecidual pulmonar foi determinada por escore histopatológico. O nível de significância adotado foi de 5%. Resultados: Ambos os grupos com lesão pulmonar aguda apresentaram piora da oxigenação após a indução da lesão comparados ao Grupo Controle. Após 4 horas, houve melhora significante da oxigenação no grupo GVAF comparado ao GVMC. A análise da capacidade antioxidante total no plasma mostrou maior proteção no GVAF. O GVAF apresentou menor escore de lesão histopatológica no tecido pulmonar que o GVMC. Conclusão: A ventilação oscilatória de alta frequência, associada à posição prona, melhora a oxigenação, e atenua o dano oxidativo e a lesão pulmonar histopatológica, comparada com ventilação mecânica convencional protetora.

ABSTRACT Objective: To compare the effects of high-frequency oscillatory ventilation and conventional protective mechanical ventilation associated with the prone position on oxygenation, histology and pulmonary oxidative damage in an experimental model of acute lung injury. Methods: Forty-five rabbits with tracheostomy and vascular access were underwent mechanical ventilation. Acute lung injury was induced by tracheal infusion of warm saline. Three experimental groups were formed: healthy animals + conventional protective mechanical ventilation, supine position (Control Group; n = 15); animals with acute lung injury + conventional protective mechanical ventilation, prone position (CMVG; n = 15); and animals with acute lung injury + high-frequency oscillatory ventilation, prone position (HFOG; n = 15). Ten minutes after the beginning of the specific ventilation of each group, arterial gasometry was collected, with this timepoint being called time zero, after which the animal was placed in prone position and remained in this position for 4 hours. Oxidative stress was evaluated by the total antioxidant performance assay. Pulmonary tissue injury was determined by histopathological score. The level of significance was 5%. Results: Both groups with acute lung injury showed worsening of oxygenation after induction of injury compared with the Control Group. After 4 hours, there was a significant improvement in oxygenation in the HFOG group compared with CMVG. Analysis of total antioxidant performance in plasma showed greater protection in HFOG. HFOG had a lower histopathological lesion score in lung tissue than CMVG. Conclusion: High-frequency oscillatory ventilation, associated with prone position, improves oxygenation and attenuates oxidative damage and histopathological lung injury compared with conventional protective mechanical ventilation.

High-frequency oscillatory ventilation associated with inhaled nitric oxide compared to pressure-controlled assist/control ventilation and inhaled nitric oxide in children: Randomized, non-blinded, crossover study.

PURPOSE: To compare the acute oxygenation effects of high-frequency oscillatory ventilation (HFOV) plus inhaled nitric oxide (iNO) with pressure-controlled assist/control ventilation (PCACV) plus iNO in acute hypoxemic respiratory failure (AHRF) children. METHODS: Children with AHRF, aged between 1 month and 14 years under PCACV with PEEP ≥ 10 cmH(2) O were randomly assigned to PCACV (PCVG, n = 14) or HFOV (HFVG, n = 14) in a crossover design. Oxygenation indexes and hemodynamic variables were recorded at enrollment (Tind), 1 hr after PCACV start (T0) and then every 4 hr (T4h, etc.). RESULTS: PO(2)/FiO(2) significantly increased after 4 hr compared to enrollment in both groups [(PCVG-Tind: 111.95 ± 37 < T4h: 143.88 ± 47.5 mmHg, P < 0.05; HFVG-Tind: 123.76 ± 33 < T4h: 194.61 ± 62.42 mmHg, P < 0.05)] without any statistical differences between groups. At T8h, PO(2)/FiO(2) was greater for HFVG compared with PCVG (HFVG: 227.9 ± 80.7 > PCVG: 171.21 ± 52.9 mmHg, P < 0.05). FiO(2) could be significantly reduced after 4 hr for HFVG (HFVG-T4h: 0.53 ± 0.09 < Tind: 0.64 ± 0.2; P < 0.05) but only after 8 hr for PCVG. Comparing groups at T8h, it was observed that FiO(2) decrease was greater for HFVG (HFVG: 0.47 ± 0.06 < PCVG: 0.58 ± 0.1; P < 0.05). CONCLUSION: Both ventilatory techniques with iNO improve oxygenation. HFOV causes earlier FiO(2) reduction and increased PO(2)/FiO(2) ratio compared to PCACV at 8 hr. However, at the end of the protocol, there was no significant difference and no clinical improvement derived from the application of both ventilatory strategies with iNO. It is not possible to say what would have happened if a different conventional ventilatory mode and a fully protective ventilatory strategy had been used, given the fact that our study is non-blind, and that a limited number of patients were included in each group.

High-frequency oscillatory ventilation attenuates oxidative lung injury in a rabbit model of acute lung injury.

Mechanical ventilation (MV) can induce lung oxidative stress, which plays an important role in pulmonary injury. This study compared protective conventional mechanical ventilation (CMV) and high-frequency oscillatory ventilation (HFOV) for oxygenation, oxidative stress, inflammatory and histopathological lung injury in a rabbit model of acute lung injury (ALI). Rabbits (n = 30) were ventilated at FiO(2) 1.0. Lung injury was induced by tracheal saline infusion (30 mL/kg, 38°C). Animals were randomly assigned to: (a) sham control (CG: tidal volume [V(T)] 6 mL/kg, positive end expiratory pressure [PEEP] 5 cmH(2)O, respiratory rate [RR] 40 ipm); (b) ALI + CMV (CMVG: V(T) 6 mL/kg, PEEP 10 cmH(2)O, RR 40 ipm); or (c) ALI + HFOV (HFG: mean airway pressure [Paw] 14 cmH(2)O, RR 10 Hz) groups. Lung oxidative stress was assessed by total antioxidant performance assay, inflammatory response by the number of polymorphonuclear leukocytes/bronchoalveolar lavage fluid/lung and pulmonary histological damage was quantified by a score. Ventilatory and hemodynamic parameters were recorded every 30 min. Both ALI groups showed worse oxygenation after lung injury induction. After four hours of ventilation, HFG showed better oxygenation (partial pressure of oxygen [PaO(2)] - CG: 465.9 ± 30.5 = HFG: 399.1 ± 98.2 > CMVG: 232.7 ± 104 mmHg, P < 0.05) and inflammatory responses (CMVG: 4.27 ± 1.50 > HFG: 0.33 ± 0.20 = CG: 0.16 ± 0.15; polymorphonuclear cells/bronchoalveolar lavage fluid/lung, P < 0.05), less histopathological injury score (CMVG: 5 [1-16] > HFG: 1 [0-5] > CG: 0 [0-3]; P < 0.05), and lower lung oxidative stress than CMVG (CG: 59.4 ± 4.52 = HFG: 69.0 ± 4.99 > CMVG: 47.6 ± 2.58% protection/g protein, P < 0.05). This study showed that HFOV had an important protective role in ALI. It improved oxygenation, reduced inflammatory process and histopathological damage, and attenuated oxidative lung injury compared with protective CMV under these experimental conditions considering the study limitations.

Interleucina-12 em crianças com sepse e choque séptico / Interleukin-12 in children with sepsis and septic shock

OBJETIVO: Examinar o comportamento da interleucina-12 e verificar se pode ser utilizada para diferenciar condições sépticas em crianças. MÉTODOS: Foram inscritas, de forma prospectiva, entre janeiro de 2004 e dezembro de 2005, crianças com idades de 28 dias a 14 anos, subdivididas nos grupos sepse (SG; n=47) e choque séptico (SSG; n=43). A interleucina-12 foi avaliada quando da admissão (T0) e 12 horas mais tarde (T12). A gravidade da doença foi avaliada utilizando o escore PRISM. RESULTADOS: A interleucina-12 não diferenciou crianças com sepse das com choque séptico quando da admissão [SSG: 0,24 (0-22,64)=SG: 1,23 (0-511,6); p=0,135)] e na avaliação T12 [SG: 6,11 (0-230,5)=SSG: 1,32 (0-61,0); p=0,1239)]. Na comparação entre os momentos, não foi observada diferença estatística para SG [SG, T0: 1,23 (0-511,6)=T12: 6,11 (0-230,5); p=0,075]. Entretanto, em casos de SSG, a interleucina-12 aumentou entre as avaliações T0 e T12 [SSG, T0: 0,24 (0-226,4)

OBJECTIVE: To examine the behavior of interleukin-12 and verify whether it can be used to differentiate septic conditions in children. METHODS: Septic children aged between 28 days and 14 years, prospectively enrolled from 01/2004 to 12/2005, were divided into sepsis (SG; n=47) and septic shock (SSG; n=43) groups. Interleukin-12 levels were measured at admission (T0) and 12 hours later (T12). Disease severity was assessed by the PRISM score. RESULTS: Interleukin-12 levels did not differentiate children with sepsis from those with septic shock at admission [SSG: 0.24 (0-226.4)=SG: 1.23 (0-511.6); p=0.135)] and T12 [SG: 6.11 (0-230.5)=SSG: 1.32 (0-61.0); p=0.1239)]. Comparing time points, no significant difference was observed in the SG [SG, T0: 1.23 (0-511.6)=T12: 6.11 (0-230.5); p=0.075]. In SSG however, interleukin-12 increased from T0 to T12 (SSG, T0: 0.24 (0-226.4)

[Red blood cell transfusion in children admitted in a pediatric intensive care unit]. / Transfusão de eritrócitos em crianças internadas em unidade de terapia intensiva pediátrica.

BACKGROUND AND OBJECTIVES: Indications of red blood cell transfusion in critically ill children are not very well determined. This study aims to describe red blood cells transfusion practice at the PICU of UNESP-Botucatu Medical School. METHODS: Retrospective observational study of all patients who received transfusion during 2003. RESULTS: Seventy five patients received transfusion and 105 indications were recorded. 53.3% of the patients were less than one year of age. Increased respiratory rate (75.2%), paleness (65.7%), and hypotension (51.4%) were the alterations more frequently recorded, before transfusion. Also, metabolic acidosis (68.08%) e and hipoxemia (63.8%) were very frequently observed. From 93 hemoglobin (Hb) values recorded, 54 (58.1%) varied from 7 to 10 g/dL and from 90 records of hematocrit (Ht) 66 (73.3%) varied from 21% to 30%. The main indications of the transfusion were anemia, in 75 children (71.4%), and active bleeding in 26 (24.7%). The mean value of Hb before transfusion was 7.82 ± 2.82 g/dL. Seven transfusions were indicated for patients with Hb levels higher than 10 g/dL (postoperative heart surgery and septic patients). CONCLUSIONS: red blood cells transfusion is carefully prescribed at the PICU by using restrictive indications (Hb between 7 and 10 g/dL). Not always is possible to find out records of the Hb levels immediately before transfusion. Hence, a protocol to better prescribe red blood cell transfusion at the PICU was adopted.

[Inhaled nitric oxide for children with acute respiratory distress syndrome]. / Óxido nítrico inalatório para crianças com síndrome do desconforto respiratório agudo.

BACKGROUND AND OBJECTIVE: The objective of this study was to review the literature on inhaled nitric oxide to children with acute respiratory distress syndrome. CONTENTS: A review of literature and selection of the most important publications on inhaled nitric oxide, using the MedLine and Cochrane Systematic Review Databases. This review was organized as follows: introduction; metabolism and biological effects; clinical applications; dosage, gas administration and weaning process; warnings and side-effects. Inhaled nitric oxide use was described in acute respiratory distress syndrome. CONCLUSIONS: Inhaled nitric oxide as the first vasodilator to produce selective pulmonary vasodilation has beneficial effects on gas exchange and ventilation, improving outcome in children with severe hypoxia. It is safe when administered in intensive care units under strict surveillance and monitoring. Further studies should be concentrated on early treatment, when acute respiratory distress syndrome is potentially reversible.

Transfusão de eritrócitos em crianças internadas em unidade de terapia intensiva pediátrica / Red blood cell transfusion in children admitted in a pediatric intensive care unit

JUSTIFICATIVA E OBJETIVOS: As indicações de transfusão de eritrócitos não estão bem estabelecidas em crianças gravemente enfermas. O objetivo deste estudo foi descrever a prática da transfusão de eritrócitos na UTI Pediátrica do Hospital de Clínicas da Universidade Estadual Paulista (HC-UNESP). MÉTODO: Estudo retrospectivo observacional realizado durante o ano de 2003. RESULTADOS: Setenta e cinco pacientes receberam transfusão, havendo registro de 105 indicações. Mais da metade dos pacientes (53,3 por cento) tinha menos que um ano de idade. Taquipnéia (75,2 por cento), palidez (65,7 por cento) e hipotensão (51,4 por cento) foram os registros mais freqüentemente observados antes da transfusão. Além disso, a gasometria evidenciou acidose metabólica (68,08 por cento) e hipoxemia (63,8 por cento). Dos 93 registros de valores de hemoglobina (Hb), 54 (58,1 por cento) estavam entre 7 e 10 g/dL e dos 90 registros de hematócrito (Ht) observou-se que 66 (73,3 por cento) apresentavam valores entre 21 por cento e 30 por cento. As principais indicações de transfusão foram anemia em 75 crianças (71,4 por cento) e sangramento ativo em 26 (24,7 por cento). O valor médio de Hb antes da transfusão foi de 7,82 ± 2,82 g/dL. Sete transfusões foram indicadas para pacientes com valores de Hb > 10 g/dL, crianças estas em pós-operatório imediato de intervenção cirúrgica cardíaca e casos de choque séptico. CONCLUSÕES: A transfusão de eritrócitos vem sendo utilizada criteriosamente, com indicações restritivas (Hb entre 7 e 10 g/dL). Nem sempre há anotação dos valores de Hb imediatamente antes da transfusão. A partir deste estudo, foi elaborado um protocolo de indicação de transfusão na unidade.

BACKGROUND AND OBJECTIVES: Indications of red blood cell transfusion in critically ill children are not very well determined. This study aims to describe red blood cells transfusion practice at the PICU of UNESP-Botucatu Medical School. METHODS: Retrospective observational study of all patients who received transfusion during 2003. RESULTS: Seventy five patients received transfusion and 105 indications were recorded. 53.3 percent of the patients were less than one year of age. Increased respiratory rate (75.2 percent), paleness (65.7 percent), and hypotension (51.4 percent) were the alterations more frequently recorded, before transfusion. Also, metabolic acidosis (68.08 percent) e and hipoxemia (63.8 percent) were very frequently observed. From 93 hemoglobin (Hb) values recorded, 54 (58.1 percent) varied from 7 to 10 g/dL and from 90 records of hematocrit (Ht) 66 (73.3 percent) varied from 21 percent to 30 percent. The main indications of the transfusion were anemia, in 75 children (71.4 percent), and active bleeding in 26 (24.7 percent). The mean value of Hb before transfusion was 7.82 ± 2.82 g/dL. Seven transfusions were indicated for patients with Hb levels higher than 10 g/dL (postoperative heart surgery and septic patients). CONCLUSIONS: red blood cells transfusion is carefully prescribed at the PICU by using restrictive indications (Hb between 7 and 10 g/dL). Not always is possible to find out records of the Hb levels immediately before transfusion. Hence, a protocol to better prescribe red blood cell transfusion at the PICU was adopted.

Óxido nítrico inalatório para crianças com síndrome do desconforto respiratório agudo: [revisão] / Inhaled nitric oxide for children with acute respiratory distress syndrome: [review]

JUSTIFICATIVA E OBJETIVOS: O objetivo desse estudo foi rever a literatura sobre a utilização de óxido nítrico inalatório em crianças com síndrome do desconforto respiratório agudo. CONTEÚDO: Revisão bibliográfica e seleção de publicações mais relevantes sobre óxido nítrico inalatório, utilizando a base de dados MedLine e Cochrane de Revisões Sistemáticas. A revisão incluiu descrição de aspectos da definição, fisiopatologia e tratamento ventilatório da síndrome do desconforto respiratório agudo, assim como o metabolismo, efeitos biológicos e aplicação clínica do óxido nítrico inalatório, comentando dose, administração e retirada do gás, precações, efeitos adversos e contra-indicações. CONCLUSÕES: O óxido nítrico, vasodilatador pulmonar seletivo, tem efeitos benéficos sobre as trocas gasosas e ventilação em crianças com hipóxia grave. É seguro quando administrado em ambiente de tratamento intensivo sob rigorosa monitorização. Estudos aleatórios e controlados devem enfocar a administração precoce do gás na síndrome do desconforto respiratório agudo, quando essa é potencialmente reversível.

BACKGROUND AND OBJECTIVE: The objective of this study was to review the literature on inhaled nitric oxide to children with acute respiratory distress syndrome. CONTENTS: A review of literature and selection of the most important publications on inhaled nitric oxide, using the MedLine and Cochrane Systematic Review Databases. This review was organized as follows: introduction; metabolism and biological effects; clinical applications; dosage, gas administration and weaning process; warnings and side-effects. Inhaled nitric oxide use was described in acute respiratory distress syndrome. CONCLUSIONS: Inhaled nitric oxide as the first vasodilator to produce selective pulmonary vasodilation has beneficial effects on gas exchange and ventilation, improving outcome in children with severe hypoxia. It is safe when administered in intensive care units under strict surveillance and monitoring. Further studies should be concentrated on early treatment, when acute respiratory distress syndrome is potentially reversible.

Sepsis em Unidade de Terapia Intensiva Pediátrica - UTIP / Sepsis in the pediatric intensive care unit - PICU

Os autores analisaram protocolos de 104 crianças com diagnóstico de sepsis, internadas na Unidade de Terapia Intensiva Pediátrica - UTIP - da Faculdade de Medicina de Botucatu, no período de um ano. Os objetivos desse estudo foram: identificar os fatores de risco envolvidos no desenvolvimento da sepsis, assim como a apresentaçäo clínica da mesma, e reavaliar a padronizaçäo de condutas do serviço e o impacto do atendimento destes pacientes, em UTIP, na reduçäo da taxa de mortalidade por sepsis. Quanto aos fatores de risco analisados, observou-se que 60(pôr cento) dos pacientes tinham menos de 6 meses de idade, 33,7 (pôr cento) apresentavam desnutriçäo protéico-calórica de III grau, 45,3 (pôr cento) foram amamentados ao seio materno apenas até o terceiro mês de vida, 75 (pôr cento) vieram de outros hospitais e 50(pôr cento) ja haviam recebido algum tipo de tratamento antibioticoterápico. Foi alta a prevalência de evoluçäo para choque séptico (62,5 pôr cento). Com relaçäo às condutas, observou-se que a maior parte dos pacientes recebeu antibioticoterapia de amplo espectro e expansäo de volume e oxigenioterapia. Também a maior parte das crianças (95 pôr cento) necessitou de suporte hemodinâmico com drogas vasoativas (dobutamina e dopamina). A taxa de mortalidade, neste estudo, foi de 22,11 (pôr cento), significativamente menor que a mortalidade encontrada por Moreira et alli, 1987 (51,7 pôr cento), no mesmo serviço, porém antes da instalaçäo da UTIP...

Comparação entre ventilação mandatória intermitente e ventilação mandatória intermitente sincronizada com pressão de suporte em crianças / Comparison between intermittent mandatory ventilation and intermittent mandatory ventilation pressure for support to children

Não há estudos que tenham comparado a ventilação mandatória intermitente (IMV) com a ventilação mandatória intermitente sincronizada associada à pressão de suporte (SIMV/PS) em crianças depois do período neonatal. Objetivos: comparar o modo IMV com o modo SIMV/PS quanto ao tempo de ventilação mecânica (TVM), tempo de desmame (TD), tempo de internação (TI) e possíveis complicações. Casuística e métodos: Ensaio clínico randomizado que incluiu crianças de 28 dias a 4 anos de idade, admitidas de 10/2002 a 06/2004 e ventiladas mecanicamente por mais de 48 horas. Os pacientes foram divididos aleatoriamente em dois grupos: grupo IMV (GIMV; n igual 35) e grupo SIMV/PS (GSIMV; n igual 35). Dados de ventilação e oxigenação foram registrados à admissão e no início do desmame. Foi, também, relatada a ocorrência de barotrauma. Pacientes com síndrome do desconforto respiratório agudo e os traqueostomizados foram excluídos. Resultados: Os grupos não diferiram quanto à idade, indicação de VM, escore PRISM, freqüência de disfunções orgânicas e evolução de parâmetros de ventilação e oxigenação. A mediana do TVM foi de 5 dias para os dois grupos (p maior que 0,05). Da mesma forma não houve diferença estatística significante quanto ao TD [GIMV: 1 dia (1 - 6) x GSIMV: 1 dia (1 - 6); p maior que 0,05] e quanto ao TI [GIMV: 8 dias (2 - 22) x GSIMV: 6 dias (3 - 20); p maior que 0,05]. Houve duas falhas de extubação em cada grupo e nenhuma criança apresentou barotrauma. Conclusões: Não houve diferença estatística entre IMV e SIMV/PS neste grupo de crianças sem IRA grave, quanto aos tempos de ventilação mecânica, desmame e internação e quanto a complicações.