Immediate changes in hemodynamics and gas exchange after initiation of noninvasive ventilation in cardiac surgical patients

[Non-invasive Mechanical Ventilation in Acute Respiratory Failure. Clinical Practice Guidelines - on behalf of the German Society of Pneumology and Ventilatory Medicine]

The guideline update outlines the advantages as well as the limitations of NIV in the treatment of acute respiratory failure in daily clinical practice and in different indications.Non-invasive ventilation (NIV) has a high value in therapy of hypercapnic acute respiratory failure, as it significantly reduces the length of ICU stay and hospitalization as well as mortality.Patients with cardiopulmonary edema and acute respiratory failure should be treated with continuous positive airway pressure (CPAP) and oxygen in addition to necessary cardiological interventions. This should be done already prehospital and in the emergency department.In case of other forms of acute hypoxaemic respiratory failure with only mild or moderately disturbed gas exchange (PaO2/FiO2 > 150 mmHg) there is no significant advantage or disadvantage compared to high flow nasal oxygen (HFNO). In severe forms of ARDS NIV is associated with high rates of treatment failure and mortality, especially in cases with NIV-failure and delayed intubation.NIV should be used for preoxygenation before intubation. In patients at risk, NIV is recommended to reduce extubation failure. In the weaning process from invasive ventilation NIV essentially reduces the risk of reintubation in hypercapnic patients. NIV is regarded useful within palliative care for reduction of dyspnea and improving quality of life, but here in concurrence to HFNO, which is regarded as more comfortable. Meanwhile NIV is also recommended in prehospital setting, especially in hypercapnic respiratory failure and pulmonary edema.With appropriate monitoring in an intensive care unit NIV can also be successfully applied in pediatric patients with acute respiratory insufficiency.

Comparison of the effect of Continuous Positive Airway Pressure (CPAP) and Bi-Level Positive Airway Pressure (BiPAP) on hemodynamic parameters in Covid-19 patients: A clinical trial

BACKGROUND

The most prevalent clinical sign for COVID-19 patients are respiratory diseases such that the criteria for clinical screening and care of the patients in most countries, including Iran, are based on the three primary symptoms, i.e., fever, cough, shortness of breath, or difficulty breathing. The purpose of the current study was to compare the effect of continuous positive airway pressure and bi-level positive airway pressure on hemodynamic parameters in COVID-19 patients.

MATERIALS AND METHODS

It was a clinical trial conducted on 46 COVID-19 patients admitted to Imam Hassan Hospital in Bojnourd in 2022. This study included patients selected through convenient sampling and then through Permuted block randomization, who were assigned to continuous positive airway pressure (CPAP), and Bi-Level Positive Airway Pressure (BiPAP) groups. Patients were compared in terms of the severity of their COVID-19 disease in both groups and were divided equally in each disease severity. After determining their type of respiratory aid use, the patient's hemodynamic status (systolic blood pressure, diastolic blood pressure, pulse, arterial oxygen saturation, and temperature) was examined beforehand, immediately after 1 hour, 6 hours, and then daily up to 3 days of CPAP/BiPAP at a specific time. Data collection tools were demographic data questionnaires and information on patients' diseases. A checklist was also used to record the main variables of the research. The collected data were put into SPSS software version 19. To analyze the data, the Kolmogorov-Smirnov normality test was used to evaluate the normality of quantitative variables. As a result, it was found that the data had a normal distribution. Repeated measures of ANOVA and independent t-tests were employed to compare quantitative variables in the two groups at different times. In this study, a significance level of 0.05 was considered.

RESULTS

There was a significant difference in terms of systolic blood pressure, diastolic blood pressure, respiration rate, pulse rate, oxygen saturation, and temperature in the two groups of patients at 1 day, 2 days, and 3 days after use (P < 0.05).

CONCLUSION

The results displayed better performance of CPAP than BiPAP in the parameters of systolic blood pressure, diastolic blood pressure, respiration rate, pulse rate, oxygen saturation, and temperature in COVID-19 patients. Therefore, in necessary cases, it is recommended to use a CPAP mask.

Factors influencing the use of postoperative bilevel positive airway pressure (BiPAP) in patients undergoing adult cardiac surgery: A retrospective cohort study

BAckground and Aims

Respiratory complications are one of the biggest challenges following cardiac surgery, which can lead to hypoxia and acute respiratory failure (ARF). The aim of this study to identify the factors led to BiPAP application for postoperative respiratory complications and its effectiveness as the main outcome measures after cardiac surgery.

Methods

It was a retrospective cohort study with consecutive sampling technique. A total of 335 postcardiac surgery patients medical record was reviewed who were underwent for surgery from November 1, 2018 to November 30, 2019. 265 patients were finalized for the recruitment, five patients were excluded before the final analysis. Data of 260 patients were analyzed for compiling of results.

Results

The mean age was 59 years. 196 (75.4%) patients were males and females were 64 (24.6%). Mean weight was 72 kg and mean body mass index (BMI) 26.67 kg/m2 . BiPAP application was in 38 (14.6%) patients and significantly high in with high BMI, (p < 0.05). There are significant associations of BiPAP application patients with COPD (p < 0.05). Patients with positive fluid balance, cardiac dysfunction, and required inotropic support were significantly associated with BiPAP need (p < 0.05), respectively.

Conclusion

BiPAP is effective to treat ARF and other respiratory complications after adult cardiac surgeries. High BMI, atelectasis, and pneumonia are also the independent factors causing ARF. BiPAP can be a successful tool for preventing the adverse effects of postoperative pulmonary complications after cardiac surgery.

Bi-level Positive Airway Pressure Versus Nasal CPAP for the Prevention of Extubation Failure in Infants After Cardiac Surgery

BACKGROUND

Extubation early in the postoperative period is beneficial to the recovery and rehabilitation of patients. This study compared the postoperative extubation failure rates among infants who received postextubation respiratory support by either bi-level positive airway pressure (BPAP) or nasal CPAP following cardiac surgery.

METHODS

This was a single-center randomized controlled trial registered at the Chinese Clinical Trial Registry (number ChiCTR2000041453) and was conducted between January 2020 and March 2021. Ventilated infants who underwent cardiac surgery were randomized to either a BPAP or a nasal CPAP group for ventilatory support following extubation. The primary outcome measure was the extubation failure rate within 48 h.

RESULTS

The analyses included 186 subjects. Treatment failure necessitating re-intubation was noted in 14 of the 93 infants (15%) in the BPAP group and in 11 of the 93 infants (12%) in the nasal CPAP group (P = .52). Moreover, there were no statistically significant differences between the 2 groups regarding the duration of noninvasive ventilation (P = .54), total enteral feeding time (P = .59), or complications (P = .85). We found that both the BPAP group and the nasal CPAP group showed significantly improved oxygenation and relief of respiratory distress after treatment. However, the P_aCO2 level within 24 h was significantly lower in the BPAP group (P = .001) than in the CPAP group. Additionally, the P_aO2 /F_IO2 in the BPAP group was significantly higher than in the nasal CPAP group at 6 h, 12 h, and 24 h after treatment (P < .001).

CONCLUSIONS

The introduction of BPAP for postextubation respiratory support was not inferior to nasal CPAP in infants after cardiac surgery. Moreover, BPAP was shown to be superior to nasal CPAP in improving oxygenation and carbon dioxide clearance.