Anesthesia for Surgery in the Lateral Position
The lateral position is necessary for certain thoracic, renal, hip, and neurosurgical procedures. While this positioning allows surgeons optimal access to the operative site in these cases, it presents unique challenges for anesthesiologists. Providing safe and effective anesthesia during surgery in the lateral position requires careful attention to airway management, ventilation, hemodynamic stability, and protection of the patient’s pressure points.
When a patient is placed in the lateral position, significant physiological changes occur compared to the more common supine position. Gravity affects ventilation and perfusion, leading to ventilation-perfusion mismatch. The dependent lung (the one closest to the operating table) typically receives greater blood flow due to gravity, but it may not ventilate as efficiently because of compression from abdominal contents or surgical positioning. Conversely, the nondependent lung may ventilate better but receives less perfusion. This imbalance can reduce oxygenation, making vigilant monitoring and ventilatory adjustments essential during anesthesia 1,2.
Securing the airway is a critical concern before turning the patient laterally. Intubation is almost always performed in the supine position, as airway access becomes more challenging once the patient is positioned on their side. After repositioning, the anesthesiologist must reassess tube placement and ensure that ventilation is not compromised. In procedures such as thoracotomy, one-lung ventilation may be required, often using a double-lumen endotracheal tube or bronchial blocker. Managing one-lung ventilation requires precise control of oxygenation and carbon dioxide levels, with careful use of positive end-expiratory pressure (PEEP) and selective oxygen supplementation as needed 3–5.
Using the lateral position for surgery can also impact circulation, another important area managed by anesthesia teams. Venous return may be reduced due to shifts in body weight, leading to changes in cardiac output and blood pressure. In addition, surgical retraction and positioning devices may exert pressure on large vessels. Continuous hemodynamic monitoring, which may involve invasive arterial lines or central venous catheters in high-risk cases, helps guide fluid and vasopressor management. Anesthesiologists must anticipate variations and be prepared to intervene promptly 6,7.
Patient safety during surgery in the lateral position extends beyond anesthesia delivery. Improper positioning can result in nerve injuries, pressure sores, or musculoskeletal strain. In collaboration with the surgical team, the anesthesiologist ensures that the head and neck are aligned, the dependent arm is supported, and padding is placed under pressure points such as the knees, elbows, and iliac crest. Special attention is required for the brachial plexus and peroneal nerve, which are at higher risk of compression injuries in this position. Eye protection is also critical to prevent corneal abrasions or pressure-related damage 8–10.
Intraoperative monitoring in the lateral position is comprehensive. Standard monitoring is supplemented with advanced tools depending on the complexity of the procedure. Continuous pulse oximetry and capnography are indispensable, while arterial blood gas analysis may be required to assess oxygenation during one-lung ventilation. Frequent reassessment of positioning, airway security, and hemodynamics is essential throughout the surgery 11,12.
Anesthesia for surgery in the lateral position requires a thorough understanding of the physiological changes that occur and the potential complications that may arise. By anticipating challenges in ventilation, hemodynamics, and patient positioning, anesthesiologists can provide safe and effective care.
References
1. O’Connor, D. & Radcliffe, J. Patient positioning in anaesthesia. Anaesthesia & Intensive Care Medicine 25, 743–748 (2024). DOI: 10.1016/j.mpaic.2024.08.003
2. Openanesthesia. Patient Positioning: Physiologic Effects. OpenAnesthesia https://www.openanesthesia.org/keywords/patient-positioning-physiologic-effects/.
3. Cui, P. et al. Tracheal intubation in the lateral position in emergency medicine: a narrative review and clinical protocol. World J Emerg Med 16, 103–112 (2025). DOI: 10.5847/wjem.j.1920-8642.2025.034
4. Morimoto, T. et al. Anesthetic management in the lateral position in a patient with Parkinson’s disease who developed severe long-seated forward flexion with the face buried between the knees: a case report. JA Clinical Reports 11, 9 (2025). DOI: 10.1186/s40981-025-00773-0
5. Meena, S. K., Pathak, S., Singh, A. & Jain, N. Lateral Positioning and Airway Management in Penetrating Abdominal Trauma: A Case Report. Cureus 17, e78466 (2025). DOI: 10.7759/cureus.78466
6. Obasuyi, B. I., Fyneface-Ogan, S. & Mato, C. N. A comparison of the haemodynamic effects of lateral and sitting positions during induction of spinal anaesthesia for caesarean section. Int J Obstet Anesth 22, 124–128 (2013). DOI: 10.1016/j.ijoa.2012.12.005
7. Yokoyama, M., Ueda, W. & Hirakawa, M. Haemodynamic effects of the lateral decubitus position and the kidney rest lateral decubitus position during anaesthesia. Br J Anaesth 84, 753–757 (2000). DOI: 10.1093/oxfordjournals.bja.a013588
8. Proper Patient Positioning Guidelines: Lateral Position. AliMed https://www.alimed.com/blogs/patient-positioning/proper-patient-positioning-guidelines-lateral-position (2023).
9. Ippolito, M. et al. The prevention of pressure injuries in the positioning and mobilization of patients in the ICU: a good clinical practice document by the Italian Society of Anesthesia, Analgesia, Resuscitation and Intensive Care (SIAARTI). J Anesth Analg Crit Care 2, 7 (2022). DOI: 10.1186/s44158-022-00035-w
10. Optimal Patient Positioning in the OR: which Fixation Systems Prevent Pressure Points and Nerve Damage? – Inspital | Innovation for Hospital. https://inspital.com/optimal-patient-positioning-in-the-or-which-fixation-systems-prevent-pressure-points-and-nerve-damage/ (2025).
11. Klein, A. A. et al. Recommendations for standards of monitoring during anaesthesia and recovery 2021. Anaesthesia 76, 1212–1223 (2021). OI: 10.1111/anae.15501
12. Checketts, M. R. et al. Recommendations for standards of monitoring during anaesthesia and recovery 2015 : Association of Anaesthetists of Great Britain and Ireland. Anaesthesia 71, 85–93 (2016). DOI: 10.1111/anae.13316