Which of the following retractors is typically used for a pneumonectomy?

The Allison lung retractor is specifically designed for use in thoracic surgery, making it particularly suitable for procedures such as pneumonectomy. Its unique shape allows surgeons to retract the lung and gain optimal access to the thoracic cavity, facilitating the removal of a lung while minimizing trauma to surrounding tissues. The curved and lightweight design of the Allison retractor helps in holding the lung away from the surgical site without causing excessive pressure that could lead to complications.

In contrast, the other retractors mentioned have different applications. The Murphy retractor is typically used in abdominal surgery and is less effective for thoracic use. The Deaver retractor, while versatile and used in various types of surgeries, does not provide the specific support needed for lung retraction. The Richardson retractor is primarily for use in abdominal procedures as well and does not offer the anatomic considerations necessary for working around the lungs. Therefore, the Allison lung retractor stands out as the most appropriate choice for pneumonectomy procedures.