Comparison of bilevel positive airway pressure and average volume-assured pressure support mode in terms of patient compliance and treatment success in hypercapnic patients. A cross-sectional study.

AIM: It is necessary for an effective NIV application to provide proper modality selection, sufficient minute ventilation (MV), also the amount of leakage on the circuit must be minimized and patient-ventilator adaptation must be achieved. METHODS: 30 patients with acute respiratory failure as a result of either internal or postoperative reasons were included in the study. Patient comfort was analyzed with a scale ranging from 0 to 2. Firstly the patient was used for two hours in BIPAP modality, after then the AVAPS modality (Period Av) was applied by setting the required rates the same mask. During BIPAP and AVAPS, arterial blood gases analysis, comfort scale and hemodynamic parameters were recorded in the 30th minute, 1st hour and 2nd hour. RESULTS: According to the assessment of arterial blood gases, the pH changes of both periods were statistically significant compared to their baseline values (p=0.001). Treatment compliance of the patients was significantly better at AVAPS modality at all times (p = 0.015, p = 0.008, p = 0.008, respectively). CONCLUSIONS: According to the results obtained from this study, the AVAPS modality has positive effects on pH and gas variation and patient comfort; therefore, it can be confidently used in clinical practice. KEY WORDS: Average Volume Assured Pressure Support, Bilevel Continuous Positive Airway Pressure, Intensive Care Units, Noninvasive Ventilation, Patients Compliance.

Non-invasive mechanical ventilation after the successful weaning: a comparison with the venturi mask / Ventilação mecânica não invasiva após desmame bem-sucedido: uma comparação com a máscara de Venturi

Abstract Background and objectives: This study compared the rates of acute respiratory failure, reintubation, length of intensive care stay and mortality in patients in whom the non-invasive mechanical ventilation (NIMV) was applied instead of the routine venturi face mask (VM) application after a successful weaning. Methods: Following the approval of the hospital ethics committee, 62 patients who were under mechanical ventilation for at least 48 hours were scheduled for this study. 12 patients were excluded because of the weaning failure during T-tube trial. The patients who had optimum weaning criteria after the T-tube trial of 30 minutes were extubated. The patients were kept on VM for 1 hour to observe the hemodynamic and respiratory stability. The group of 50 patients who were successful to wean randomly allocated to have either VM (n = 25), or NIV (n = 25). Systolic arterial pressure (SAP), heart rate (HR), respiratory rate (RR), PaO2, PCO2, and pH values were recorded. Results: The number of patients who developed respiratory failure in the NIV group was significantly less than VM group of patients (3 reintubation vs. 14 NIV + 5 reintubation in the VM group). The length of stay in the ICU was also significantly shorter in NIV group (5.2 ± 4.9 vs. 16.7 ± 7.7 days). Conclusions: The ratio of the respiratory failure and the length of stay in the ICU were lower when non-invasive mechanical ventilation was used after extubation even if the patient is regarded as ‘successfully weaned’. We recommend the use of NIMV in such patients to avoid unexpected ventilator failure.

Resumo Justificativa e objetivos: Este estudo comparou as taxas de insuficiência respiratória aguda, reintubação, tempo de internação em UTI e mortalidade em pacientes sob ventilação mecânica não invasiva (VMNI) em vez da habitual máscara facial de Venturi (MV) após desmame bem-sucedido. Métodos: Após a aprovação do Comitê de Ética do hospital, 62 pacientes que estavam sob ventilação mecânica por no mínimo 48 horas foram inscritos neste estudo. Doze foram excluídos devido à falha de desmame durante o teste de tubo-T. Os que apresentaram critérios de desmame ótimos após o teste de tubo-T de 30 minutos foram extubados. Foram mantidos em MV por uma hora para observação da estabilidade hemodinâmica e respiratória. O grupo de 50 pacientes que obtiveram sucesso no desmame ventilatório foi alocado aleatoriamente para MV (n = 25) ou VNI (n = 25). Os valores de pressão arterial sistólica (PAS), frequência cardíaca (FC), frequência respiratória (FR), PaO2, PCO2 e pH foram registrados. Resultados: O número de pacientes que desenvolveu insuficiência respiratória no grupo VNI foi significativamente menor do que o do grupo MV (3 reintubações vs. 14 VNI + 5 reintubações no grupo MV). O tempo de permanência em UTI também foi significativamente menor no grupo NIV (5,2 ± 4,9 vs. 16,7 ± 7,7 dias). Conclusões: As taxas de insuficiência respiratória e do tempo de permanência em UTI foram menores quando a ventilação mecânica não invasiva foi usada após a extubação, mesmo se o paciente foi considerado como “desmame bem-sucedido”. Recomendamos o uso de VMNI em tais pacientes para evitar a falha inesperada do ventilador.

Non-invasive mechanical ventilation after the successful weaning: a comparison with the venturi mask.

BACKGROUND AND OBJECTIVES: This study compared the rates of acute respiratory failure, reintubation, length of intensive care stay and mortality in patients in whom the non-invasive mechanical ventilation (NIMV) was applied instead of the routine venturi face mask (VM) application after a successful weaning. METHODS: Following the approval of the hospital ethics committee, 62 patients who were under mechanical ventilation for at least 48hours were scheduled for this study. 12 patients were excluded because of the weaning failure during T-tube trial. The patients who had optimum weaning criteria after the T-tube trial of 30minutes were extubated. The patients were kept on VM for 1hour to observe the hemodynamic and respiratory stability. The group of 50 patients who were successful to wean randomly allocated to have either VM (n=25), or NIV (n=25). Systolic arterial pressure (SAP), heart rate (HR), respiratory rate (RR), PaO2, PCO2, and pH values were recorded. RESULTS: The number of patients who developed respiratory failure in the NIV group was significantly less than VM group of patients (3 reintubation vs. 14 NIV+5 reintubation in the VM group). The length of stay in the ICU was also significantly shorter in NIV group (5.2±4.9 vs. 16.7±7.7 days). CONCLUSIONS: The ratio of the respiratory failure and the length of stay in the ICU were lower when non-invasive mechanical ventilation was used after extubation even if the patient is regarded as 'successfully weaned'. We recommend the use of NIMV in such patients to avoid unexpected ventilator failure.

[Non-invasive mechanical ventilation after the successful weaning: a comparison with the venturi mask]. / Ventilação mecânica não invasiva após desmame bem­sucedido: uma comparação com a máscara de Venturi.

BACKGROUND AND OBJECTIVES: This study compared the rates of acute respiratory failure, reintubation, length of intensive care stay and mortality in patients in whom the non-invasive mechanical ventilation (NIMV) was applied instead of the routine venturi face mask (VM) application after a successful weaning. METHODS: Following the approval of the hospital ethics committee, 62 patients who were under mechanical ventilation for at least 48hours were scheduled for this study. 12 patients were excluded because of the weaning failure during T-tube trial. The patients who had optimum weaning criteria after the T-tube trial of 30minutes were extubated. The patients were kept on VM for 1hour to observe the hemodynamic and respiratory stability. The group of 50 patients who were successful to wean randomly allocated to have either VM (n=25), or NIV (n=25). Systolic arterial pressure (SAP), heart rate (HR), respiratory rate (RR), PaO2, PCO2, and pH values were recorded. RESULTS: The number of patients who developed respiratory failure in the NIV group was significantly less than VM group of patients (3 reintubation vs. 14 NIV+5 reintubation in the VM group). The length of stay in the ICU was also significantly shorter in NIV group (5.2±4.9 vs. 16.7±7.7 days). CONCLUSIONS: The ratio of the respiratory failure and the length of stay in the ICU were lower when non-invasive mechanical ventilation was used after extubation even if the patient is regarded as "successfully weaned". We recommend the use of NIMV in such patients to avoid unexpected ventilator failure.