Answer:

Robotic thoracic procedures present some unique challenges when compared to VATS despite both being minimally invasive.

In both cases, patients are positioned in the lateral decubitus and the bed may be flexed. However, for robotic cases, the bed may also be rotated 90 to 180 degrees from the original position to allow docking of the robot and hence far away from the anesthesiologist. Extensions for the intravenous tubing and the breathing circuit may be necessary. Special care is required for the upper arm, which is suspended and sometimes abducted to facilitate the robotic arms motion. Unnatural positioning with stretching of the brachial plexus can lead to potentially permanent damage. Direct injury can also result from the robotic arms resting on the patient’s arm or head.

Optimal lung isolation and collapse are needed to enhance lung visualization during the case and allow full motion of the instruments in the chest cavity. Because this space remains partially closed, lung collapse is slower than for the open approach. Carbon dioxide (CO₂) insufflation may be used to expedite the process. Left DLTs are commonly used due to less chance of displacement and the ability to quickly collapse the lung. Once the patient is positioned and the robot docked, it may be difficult to gain access to the airway. Bronchial blockers may be an alternative, but they may require repositioning during the case.

Intravenous access should be placed before final positioning and draping because patient access will be limited. Although not uniformly regarded as necessary for lung resection via thoracotomy, an arterial catheter, generally in the dependent radial artery, may be beneficial in patients undergoing robotic procedures for hemodynamic monitoring especially if the chest will be insufflated with CO₂. This 'iatrogenic tension pneumothorax' can be associated with a transient increase in peak airway pressures and a decrease in venous return with significant hypotension and decreased lung compliance. In most cases, this is transient and effectively treated with pressors and/or temporary decrease of the insufflation pressures. Suggested insufflation pressure should be less than 10 to 15 mmHg, whereas peak inspiratory pressures should be less than 30 cm H₂O. Minute ventilation should be adjusted to maintain normocapnia while complying with protective lung ventilation guidelines.

Hemodynamic compromise can also be caused by unexpected bleeding, arrhythmias, or, in rare cases, contralateral pneumothorax (more common during robotic esophagectomy). Bleeding can be more difficult to control in robotic cases than VATS because the robotic arms limit the access to the chest, causing delays in making an incision or performing CPR. Helpful maneuvers to decrease bleeding involve increasing the CO₂ insufflation pressure (potentially worsening systemic hypotension) and allowing periods of apnea to decrease mediastinal movement and facilitate compression/clipping of the source of bleeding.

Robotic resections tend to take longer than open procedures or VATS, with duration influenced by experience of the surgical team and the need for added equipment. As a consequence, exposure to anesthesia and lung collapse may be prolonged, and intraoperative costs are increased.

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