Non-invasive Ventilation in Solid Transplantation

Abstract

Atelectasis, postoperative pneumonia, pulmonary edema, acute respiratory failure are common postoperative pulmonary complications and are a significant issue increasing hospital length of stay, morbidity, mortality, and healthcare costs (Chiumello et al., Intensive Care Med 37:918–929, 2011; Magnusson, Br J Anaesth 91:61–72, 2003). General anesthesia usually induces atelectasis in the most dependent parts of the lung, near the diaphragm and lower lobes, because of the reduction in lung gas volumes (Chiumello et al., Intensive Care Med 37:918–929, 2011). Atelectasis can persist for days in the postoperative period and may contribute to significant impaired oxygenation, increased shunting, and decreased pulmonary compliance (Magnusson, Br J Anaesth 91:61–72, 2003).

Hyperinflation during mechanical ventilation or a deep breath in spontaneous ventilation substantially reduces atelectasis (Magnusson, Br J Anaesth 91:61–72, 2003).

Diaphragm, abdominal and thoracic respiratory muscles weakness, caused by surgery, neuromuscular blocking drugs, mechanical ventilation, and postoperative pain, will occur in the first hours after surgery and may persist up to weeks; this condition is associated with an increase in carbon dioxide, ventilation-perfusion mismatching, hypoxemia and could lead to Acute Respiratory Failure (ARF) (Chiumello et al., Intensive Care Med 37:918–929, 2011; Magnusson, Br J Anaesth 91:61–72, 2003). ARF severity depends on preoperative pulmonary conditions and perioperative-related ventilatory impairment.

For Intensive Care Unit (ICU), specialists are mandatory to prevent pulmonary complications and when ARF occurs to avoid reintubation because of several studies have shown that major respiratory problems are related to invasive mechanical ventilation (Riou et al., Anesthesiology 112:453–61, 2010). Intubation and reintubation, rather than duration of respiratory support, expose the patient to a greater probability of lung complications (Feltracco et al., Transplant Proc 40:1979–1982, 2008). The goal is to ensure oxygen administration and carbon dioxide removal without endotracheal tube or tracheotomy using Noninvasive Ventilation (NIV) to prevent ARF occurrence (prophylactic treatment) or to treat ARF (Riou et al., Anesthesiology 112:453–61, 2010).

Organ transplantation became every year more the optimal therapy for patients affected by end-stage organ failure. Preventing organ rejection is challenging and remains the main transplantation’s problem but pulmonary complication contributes significantly to overall morbidity and mortality. Approximately 5% of patients undergoing renal, hepatic, cardiac, or pulmonary transplantation develop pneumonia in the period after transplantation, which has an associated crude mortality of 37% (Antonelli et al., JAMA 283:235–41, 2000).