RESUMO
OBJECTIVES: To evaluate the effects of the manual hyperinflation with thoracic compression (MHTC) maneuver on the clearance of secretions, pulmonary mechanics, hemodynamics and oxygenation in mechanically ventilated patients. METHODS: This was a controlled, crossover study that included twenty patients who were under invasive ventilation for more than 48 hours. Four hours after the last airway suctioning procedure, the patients underwent the study interventions, Suction alone or MHTC plus Suction, in sequence at four hour intervals. The sequence order for the procedures was established by randomization. Data were collected before, during and 5, 15, 30 and 60 minutes after each intervention. The suctioned secretions were collected and weighed. RESULTS: No significant differences between the procedures were found regarding tidal volume, plateau pressure and pulmonary compliance (p>0.05). The hemodynamic variables showed increased pressures and heart rate during the procedures and returned to baseline values five minutes after the end of the procedure (p≤0.001). No significant hemodynamic differences were seen between the interventions (p>0.05). For the duration of the study, oxygen saturation was 99% with only two exceptions during the MHTC + Suction procedure, where saturation was 98% (p<0.05). No significant differences were observed between the techniques regarding the weight of the suctioned secretion. CONCLUSION: The results suggest that MHTC, as performed in this study, adds no benefit with respect to oxygenation optimization, pulmonary mechanics and clearance of secretions. However, the MHTC maneuver did not result in hemodynamic changes when compared to the suctioning procedure alone.
RESUMO
OBJETIVOS: Avaliar os efeitos da manobra hiperinsuflação manual com compressão torácica em termos de depuração de secreções, mecânica pulmonar, hemodinâmica e oxigenação em pacientes sob ventilação mecânica invasiva. MÉTODOS: Foi realizado estudo controlado do tipo cruzado, com vinte pacientes com mais de 48 horas em ventilação mecânica invasiva. Após 4 horas da última aspiração os pacientes foram submetidos aos procedimentos, aspiração ou hiperinsuflação manual com compressão torácica e aspiração, um após o outro, respeitando intervalo de quatro horas, em ordem estabelecida conforme randomização. As variáveis foram coletadas nos momentos pré, durante e após 5, 15, 30 e 60 minutos do término dos procedimentos. A secreção aspirada foi coletada e mensurada. RESULTADOS: Não foram encontradas alterações significativas para o volume corrente, pressão platô e complacência após os dois procedimentos durante o estudo (p>0,05). As variáveis hemodinâmicas apresentaram comportamento distinto ao longo do tempo caracterizado por aumento das pressões e frequência durante a realização dos procedimentos, com retorno aos valores basais após 5 minutos das intervenções (p≤0,001). Não foi encontrada diferença no comportamento hemodinâmico entre os procedimentos (p>0,05). A saturação de oxigênio durante todos os momentos do estudo foi 99 por cento, com exceção de dois momentos durante a realização da HMCT+ASP que foi 98 por cento (p<0,05). Não houve diferença significante entre as técnicas em relação ao peso das secreções aspiradas. CONCLUSÃO: Os resultados sugerem que a hiperinsuflação manual com compressão torácica, conforme aplicada neste estudo, embora tenha se mostrado segura hemodinamicamente, não apresentou benefícios em relação à técnica de aspiração isolada em termos de otimização da oxigenação, mecânica respiratória e depuração de secreções.
OBJECTIVES: To evaluate the effects of the manual hyperinflation with thoracic compression (MHTC) maneuver on the clearance of secretions, pulmonary mechanics, hemodynamics and oxygenation in mechanically ventilated patients. METHODS: This was a controlled, crossover study that included twenty patients who were under invasive ventilation for more than 48 hours. Four hours after the last airway suctioning procedure, the patients underwent the study interventions, Suction alone or MHTC plus Suction, in sequence at four hour intervals. The sequence order for the procedures was established by randomization. Data were collected before, during and 5, 15, 30 and 60 minutes after each intervention. The suctioned secretions were collected and weighed. RESULTS: No significant differences between the procedures were found regarding tidal volume, plateau pressure and pulmonary compliance (p>0.05). The hemodynamic variables showed increased pressures and heart rate during the procedures and returned to baseline values five minutes after the end of the procedure (p≤0.001). No significant hemodynamic differences were seen between the interventions (p>0.05). For the duration of the study, oxygen saturation was 99 percent with only two exceptions during the MHTC + Suction procedure, where saturation was 98 percent (p<0.05). No significant differences were observed between the techniques regarding the weight of the suctioned secretion. CONCLUSION: The results suggest that MHTC, as performed in this study, adds no benefit with respect to oxygenation optimization, pulmonary mechanics and clearance of secretions. However, the MHTC maneuver did not result in hemodynamic changes when compared to the suctioning procedure alone.