الفهرس 
The supine PositionOnly 14 pages are availabe for public view
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Abstract
SUMMARY
This essay deals with different positions, which may be attained by the patient
during anaesthesia, and hazards in relation to each of them. The following pages sum up the various positions and different complications.
The Supine Position:
Describes a patient placed flat on his back on the operating table with his arms by his sides.
Brachial plexus injury may occur in this position due to dorsal extension and lateral flexion of the head to the opposite side. Prevention of this injury is made by permitting the arm to sag off the side of the table and slight flexion of the neck. Injury to the ulnar nerve may occur also in this position by sharp edge of the operating table. The radial nerve may be injured if the arm is permitted to slip off the side of the operating table. The supraorbital nerve can be compressed by the metal connector of a tracheal tube in this position. Injury of common peroneal nerve may be produced by hard rolls, this can be avoided by adequate padding of the leg.
The Prone Position:
In the prone position, the patient lies with the ventral surface of the body against the supporting surface. Hypotension and impaired ventilation are the most important sequelae of this position and are due to pressure of the abdomen against the supporting surface. They can be avoided by permitting the abdomen to hang free. Facial nerve, and nerves of the dorsum of the foot may be injured by improper position. The eyes may be contused or penetrated, male genitalia and female breasts
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also may be injured in the prone position.
The Sitting Position:
Describes the posture of a patient whose back is elevated toward the vertical,
whose thighs are flexed on the trunk, whose legs are flexed on the thighs and whose feet at the appropriate level of the heart. Its main complications are hypotension, air embolism, arrhythmias, endotracheal tube migration and respiratory acid-base imbalance. Sciatic nerve may be stretched by failure of flexion of the knees. Oedema of the face, neck and Macroglossia may also result from extreme flexion of the neck for long periods.
The Trendelenburg Position:
This position describes a patient lying supine with his head at lower level than
his heart and his legs elevated. Pulmonary congestion and oedema, hypotension and cerebral venous congestion and oedema may develop in this position.
The shoulder rests used to support the body are a common cause of brachial plexus injury. This can be avoided by placing the rests against the acromioclavicular junction and not over the clavicle. The circumflex nerve and radial nerve may be compressed between bone and metal ether screen. This can be prevented by proper placing of the arm of the patient under the ether screen.
The Lithotomy Position:
It describes a patient lying supine with the thighs flexed on the trunk and the legs flexed on the thighs.
Sciatic nerve may be injured if the thighs are extremely externally rotated or
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if the knees are extended. This can be avoided by minimizing the external rotation of the thighs and flexion of the knees. Also the common peroneal nerve may be compressed against the head of the fibula in this position. Posterior tibial and saphenous nerves may be injured in the lithotomy position. Adequate padding avoid these injuries. Other cutaneous and musculoskeletal injuries may occur in this position.
The Lateral Decubitus Position:
It describes the position in which the patient lies on his sound side with the
diseased side up. It predisposes to alveolar collapse and atelectasis. This can be avoided, if the patient is left to breath spontaneously.
Buccal branch of the facial nerve may be injured by pressure from a head strap applied too tightly. Brachial plexus injury of the dependent part may occur. Also common peroneal nerve may be damaged due to prolonged pressure against the nerve by a poorly padded table. Oedema, distortion of deltoid muscle of the dependent arm developed after long period of operation. These complications can be avoided by adequate padding of the dependent part.
No doubt that some procedures as cholecystectomies, dental procedures, orthopaedics and regional blocks may require variable modifications in these positions. These modifications may carry various complications to the patient. However this is the duty of the anesthesiologist to take care of such complications to deal with if they happened.