Browse the corpus

Lung isolation involves the anatomical or physiological separation of 1 lung from the other using advanced airway devices such as bronchial blockers or double-lumen endotracheal tubes. Anatomical lung isolation is crucial for preventing contamination from a diseased lung to a healthy one, such as in whole lung lavage to avoid spillage of blood or pus. Physiological lung separation allows each lung to be ventilated independently. One-lung ventilation is vital for creating an immobile surgical field and providing access to anatomical structures by allowing 1 lung to collapse. Simulator training and deliberate practice models prove beneficial in lung isolation, particularly for clinicians who use these skills infrequently. In addition, establishing a clear plan, including the choice of devices and emergency protocols, ensures preparedness and improves patient safety during lung isolation procedures. This activity describes the technical and physiological principles relevant to lung isolation, emphasizing that proficiency in these techniques requires continuous practice and interprofessional coordination to enhance patient outcomes. This activity underscores the crucial role of an interprofessional healthcare team, including anesthesiologists, thoracic surgeons, and operating room nurses, in treating patients by ensuring clear communication and established protocols to prevent and manage complications, thereby enhancing patient safety. Objectives: Identify the anatomical and physiological principles underlying lung isolation. Assess the patient's response to one-lung ventilation and adjust ventilatory parameters as needed to prevent hypoxia. Apply simulator training and deliberate practice models to maintain proficiency in lung isolation techniques. Collaborate with interprofessional healthcare teams, including anesthesiologists, thoracic surgeons, and operating room nurses, to ensure a shared understanding of the lung isolation plan, thereby enhancing patient outcomes. Access free multiple choice questions on this topic.

Lung isolation involves the anatomical or physiological separation of 1 lung from the other using advanced airway devices such as bronchial blockers or double-lumen endotracheal tubes. Anatomical lung isolation is crucial for separating the diseased lung and preventing contamination of the healthy lung. For example, in the case of whole lung lavage, anatomical lung isolation is used to avoid spillage of blood or pus from the diseased to the healthy lung. Physiological lung separation allows each lung to be ventilated independently and may be indicated when unilateral lung pathology requires different ventilatory parameters for each lung. One-lung ventilation involves ventilating 1 lung while allowing the other to collapse, thereby facilitating surgical exposure or managing disease states. The deflation of 1 lung can create an immobile surgical field and provide space within the thorax, allowing access to anatomical structures. A clinician with advanced airway training (eg, an anesthesiologist or intensivist) should place the double-lumen endotracheal or bronchial blocker. Extensive knowledge of pulmonary physiology is essential for managing lung isolation, particularly during periods of one-lung ventilation, which can be complicated by hypoxia. When used to facilitate surgery, lung isolation requires clear communication between the surgical and anesthesiology teams to prevent and manage complications. In the intensive care unit (ICU) setting, nurses and respiratory therapists must be aware of the physiological consequences of differential or one-lung ventilation and detect changes in the patient's condition that may indicate a problem with lung isolation.

Anatomical Complications Because of its larger caliber than a single-lumen tube, a double-lumen tube is more likely to cause trauma to the larynx, trachea, or bronchi. Iatrogenic tracheobronchial ruptures are rare but potentially devastating complications of double-lumen endotracheal tube placement. Women, older adults, patients of small stature, patients taking corticosteroids, and those with certain tracheal pathologies, including tracheomalacia and congenital anomalies, are more likely to experience these injuries. Postoperative hoarseness and sore throat are more common after double-lumen endotracheal tube placement than bronchial blocker placement.[20][35] Physiological Complications During single-lung ventilation, ventilation to 1 lung is interrupted, but perfusion continues in the nonventilated lung. This leads to an intrapulmonary shunt, resulting in wasted perfusion to the nonventilated lung. Protective mechanisms like hypoxic pulmonary vasoconstriction can counteract hypoxia to a certain degree. However, the anesthesiologist must be prepared to manage hypoxemia that may arise during single-lung ventilation. Ventilation and perfusion (V/Q) matching significantly impact oxygenation in patients on single-lung ventilation. Some authors note that oxygenation is significantly better in the lateral decubitus position than in the supine position.[36] The fraction of inspired oxygen (FiO2) of 1.0 has been advocated while performing single-lung ventilation. The rationale behind using a higher FiO2 is to have a safety margin. Higher FiO2 also leads to vasodilatation, which may help increase the blood to the ventilated lung. However, oxygenation at FiO2 of 1.0 can lead to atelectasis, so initiating with a FiO2 less than 1.0 is advisable and increasing if needed. If hypoxia develops during the performance of single-lung ventilation, the following steps must take place: The position of the double-lumen, endobronchial, or bronchial blocker should be checked. Changes in position may occur due to surgical manipulation. A repeat fiberoptic bronchoscopy through the tracheal lumen is helpful in clinching the diagnosis. Additional steps involve suctioning the tube lumens to clear secretions that may contribute to hypoxia. FiO2 is increased to 1.0 to improve the amount of oxygen delivered.

The position of the double-lumen, endobronchial, or bronchial blocker should be checked. Changes in position may occur due to surgical manipulation. A repeat fiberoptic bronchoscopy through the tracheal lumen is helpful in clinching the diagnosis. Additional steps involve suctioning the tube lumens to clear secretions that may contribute to hypoxia. FiO2 is increased to 1.0 to improve the amount of oxygen delivered. Recruitment maneuvers are used on the ventilated lung, which is in the dependent position, to overcome any atelectasis and thus help with oxygenation. Positive end-expiratory pressure (PEEP) may be applied to this lung to eliminate atelectasis, decrease the shunt, and improve oxygenation. Continuous positive airway pressure may be applied to the operative lung to decrease shunting and improve oxygenation. However, this makes the surgical procedure challenging for the surgeon and should only be an option when other measures have not improved the hypoxia. If the hypoxemia is severe and does not resolve with the abovementioned steps, the next best step is to revert to two-lung ventilation. Severe hypoxemia should alert the anesthesiologist to look for causes such as pneumothorax on the dependent lung. Patients with chronic chronic obstructive pulmonary disease (COPD) are more likely to experience such a complication. The intraoperative development of pneumothorax mandates aborting the surgical procedure and the immediate insertion of a chest tube on the side of the pneumothorax. Using standardized protocol has increased adherence to lung-protective strategies.[23]

Effective interprofessional communication between the operative and anesthesia teams is essential. Before starting the procedure, a plan for achieving lung isolation should be established, including selecting the most appropriate devices for the clinical scenario. Establishing a plan for lung isolation in a patient with a difficult airway is particularly crucial. Emergency airway equipment, including that required for a surgical airway, should be readily accessible. Perioperative nurses and anesthesia technicians should ensure all necessary equipment is ready and functioning. This interprofessional interplay among healthcare team members can significantly improve patient outcomes. Conflicting evidence exists regarding whether a double-lumen endotracheal tube or bronchial blocker provides more rapid achievement of lung isolation or complete lung collapse. Equipment choice may hinge upon clinician preference and experience.[15][16][44] Larger medical centers may have dedicated thoracic anesthesia teams comprised of select clinicians who maintain their proficiency and become experts in lung isolation. In smaller centers, this is usually not the case, leading to relatively inexperienced clinicians performing lung isolation techniques sporadically. Inexperienced clinicians take 2 to 3 times longer to place these devices, and their positioning failure rates approach 40%.[45] Whether simulator training could help maintain proficiency in lung isolation techniques for clinicians who only occasionally use these skills in the clinical setting is uncertain.

Managing lung isolation patients in the ICU requires a team of clinicians, including intensivists, nurses, and respiratory therapists. Usually, a double-lumen endotracheal tube is used to maintain lung isolation, and all care team members should be familiar with the device. Because lung isolation in the ICU is relatively rare, anesthesiology team members should be prepared to provide education and support if necessary. If both lungs are to be ventilated but with different ventilator settings, the respiratory therapist will provide and maintain 2 separate ventilators for each side. The nursing team should consistently perform aggressive pulmonary toilet practices, including frequent suctioning of both lumens and meticulous oral care. If lung isolation is implemented due to unilateral infection, it is crucial to avoid contaminating the healthy lung with the diseased lung by using different suction tubing for each side. Particular attention is necessary during patient transport, turning, or other activities when the double-lumen endotracheal tube is at risk of dislodging from the correct position.

When lung isolation and one-lung ventilation are performed in the critical care setting, nurses are primarily responsible for monitoring patients for any signs indicating a problem with lung isolation. A significant change in respiratory status, such as hypoxemia, hypercarbia, or high peak airway pressures, should prompt notification of an intensivist or anesthesiologist to verify the correct device placement. Changes in the quality or quantity of suctioned secretions from each lung should also be monitored.