From the Guidelines
Prolonged steep Trendelenburg positioning can cause several medical conditions, including facial and conjunctival edema, increased intraocular pressure, potential airway edema, and respiratory compromise, as well as cerebral edema, increased intracranial pressure, and venous congestion in the head and neck, as evidenced by studies such as 1 and 1. The most common conditions associated with prolonged steep Trendelenburg positioning include:
- Facial and conjunctival edema
- Increased intraocular pressure
- Potential airway edema
- Respiratory compromise
- Cerebral edema
- Increased intracranial pressure
- Venous congestion in the head and neck These complications occur because the head-down position causes fluid shifts toward the upper body, increases hydrostatic pressure in the head and thorax, and can compromise respiratory mechanics by pushing abdominal contents against the diaphragm, as noted in 1. To minimize these risks, medical teams should:
- Limit time in steep Trendelenburg position to the shortest duration necessary
- Ensure proper padding and positioning
- Monitor vital signs closely
- Gradually return patients to a flat position It is also important to consider the use of alternative positions, such as the reverse Trendelenburg position, to reduce the risk of complications, as suggested in 1. In addition, the use of algorithms and protocols, such as those outlined in 1, can help to limit the incidence of complications associated with extubation and tracheal tube management. Overall, the key to minimizing the risks associated with prolonged steep Trendelenburg positioning is to carefully consider the potential complications and take steps to mitigate them, as supported by the evidence from studies such as 1, 1, and 1.
From the Research
Conditions Caused by Prolonged Steep Trendelenburg Position
- Cerebral haemodynamic changes: The steep Trendelenburg position can affect cerebral blood flow and zero flow pressure (ZFP) 2.
- Increased intrathoracic pressure: Prolonged steep Trendelenburg position can lead to increased intrathoracic pressure, which may affect circulation 3.
- Atelectasis formation: The steep Trendelenburg position can contribute to atelectasis formation, which can be reduced by positive end-expiratory pressure (PEEP) 4, 5.
- Hemodynamic depression: Sustained continuous negative abdominal pressure in the steep Trendelenburg position can cause hemodynamic depression and lactic acidosis 4.
- Respiratory complications: Prolonged steep Trendelenburg position can lead to respiratory complications, such as decreased lung volume and impaired gas exchange 6, 3.
Factors Influencing the Conditions
- Duration of the steep Trendelenburg position: Prolonged steep Trendelenburg positioning can increase the risk of cerebral haemodynamic changes and respiratory complications 2.
- Level of PEEP: High PEEP can improve oxygenation and respiratory mechanics, but may also increase intrathoracic pressure and affect circulation 6, 3.
- Patient positioning: The steep Trendelenburg position can optimize surgical exposure, but may also contribute to atelectasis formation and respiratory complications 4, 5.