ABSTRACT
Mild to severe respiratory dysfunction is still a common issue after cardiac surgery. Postoperative respiratory complications are associated with prolonged hospitalization and worse survival. In this high-risk surgery, non-invasive ventilation could have relevant positive effects. The present narrative concise review aims to summarize available data on the role of non-invasive ventilation before and after cardiac surgery. Non-invasive ventilation exerts its main effects on the pulmonary and on the cardiovascular systems. Non-invasive ventilation can be applied to prevent acute respiratory failure; it can also be prescribed as a curative tool to treat an established postoperative acute respiratory failure. Non-invasive ventilation could also be applied to wean patients from mechanical ventilation. When applied as a preventive tool, the main scope is the prevention of pneumonia by resolving or preventing atelectasis. So far, limited (but encouraging) data are available: its routine use in all patients to prevent postoperative acute respiratory failure cannot be recommended. Non-invasive ventilation to treat postoperative acute respiratory failure has been evaluated more extensively. A failure rate from 10 to 55% was reported. Safety appears preserved, with no relevant hemodynamic complication reported. Non-invasive ventilation has also been applied during percutaneous aortic valve implant in patients unable to lie supine due to severe respiratory limitation and orthopnea. In conclusion, non-invasive ventilation has the potential to be very useful before and after cardiac surgery. So far, results are promising but available data are limited. Training and experience are essential to obtain positive results and to avoid complications.
ABSTRACT
BACKGROUND: Upper endoscopies (UE) are widely performed. Non-invasive ventilation (NIV) during UE has been used to avoid respiratory complications, mainly in high-risk or sedated patients. We performed a systematic review on this topic. METHODS: BioMedCentral, PubMed, Embase and the Cochrane Central Register of Clinical Trials were searched (updated September 1, 2012). Further searches involved conference proceedings. RESULTS: We included in this systematic review 27 papers out of 405 publications retrieved. Ten studies reported the use without complications of NIV to assist fiberoptic bronchoscopy (FOB) and broncho-alveolar lavage (BAL). Ten studies described the use of NIV in fiberoptic-guided tracheal intubations. The authors reported no complications, even in hypoxemic patients and they observed only one failure (0.4%). Three studies evaluated the effectiveness of NIV during placement of percutaneous endoscopic gastrostomy in patients with neuromuscular diseases. In this group the failure rate was 4.4%. One study described the successful use of NIV in sedated patients undergoing gastroscopy. Three studies reported the successful application of NIV during trans-esophageal echocardiography. Overall, the procedure could not be performed due to inability of NIV to maintain safe intra-procedural ventilation in four out of total 515 cases of NIV-aided UE, suggesting a success rate higher than 99.2%. CONCLUSION: This is the first systematic review addressing the use of NIV during upper endoscopies. Its use seems feasible, and based on the limited data available NIV appears safe and likely effective. The patients who would benefit the most are: high-risk and patients undergoing sedation.
