Chapter 16 Patient Positioning and Associated Risks
1. Whose responsibility is the intraoperative position of the anesthetized patient?
2. How does the lack of response to pain affect the positions that are tolerated by patients under general anesthesia? What is the clinical implication of this?
3. What are potential injuries to the patient that can be sustained during mask ventilation of the airway?
4. What areas of skin are especially prone to ischemic damage during surgery? How can this risk be minimized?
Specific positions
5. What are the cardiovascular effects of placing the patient in the supine position for a surgical procedure?
6. How does the supine position affect lung perfusion?
7. How does the functional residual capacity change when a patient’s position is changed from standing to supine?
8. How should the patient’s legs be ideally positioned during surgery in the supine position?
9. Why might focal alopecia result following surgery?
10. Why might backache result from surgery in the supine position?
11. What are some potential positions the patient’s arms may be placed in while the patient is in the supine position for surgery?
12. Describe how the patient’s arms should be positioned when the patient is supine and the arms are abducted.
13. Describe how the patient’s arms should be positioned when the patient is supine and the arms are adducted.
14. What are the cardiovascular effects of placing the patient in the head-down position, or Trendelenburg position, for a surgical procedure?
15. What are the pulmonary effects of placing the patient in the Trendelenburg position for a surgical procedure?
16. How does the Trendelenburg position affect the patient’s intracranial pressure?
17. What is a potential complication of the use of shoulder braces to prevent the patient from sliding off the table while in a steep Trendelenburg position?
18. How does the prone position affect the patient’s ventilatory mechanics? How can this effect be offset?
19. What are the cardiovascular effects of placing the patient in the prone position for a surgical procedure? How can this potential problem be minimized?
20. What are the potential problems with turning the prone patient’s head laterally?
21. What is a potential problem with placing the prone patient’s head in a neutral forward-facing position, as in a Mayfield headrest? How can this potential problem be minimized?
22. How should the patient’s arms be positioned while in the prone position?
23. How can venous pooling in the lower extremities be offset while the patient is in the prone position, as during a laminectomy?
24. How does the lateral decubitus position affect the patient’s ventilatory mechanics and ventilation-perfusion ratio during mechanical ventilation of the lungs? How might these effects of the lateral decubitus position be manifest clinically?
25. What are the cardiovascular effects of placing the patient in the lateral decubitus position for a surgical procedure?
26. What is the purpose of the axillary roll for patients who are placed in the lateral decubitus position? What monitoring may be helpful?
27. How should the patient’s head and neck be positioned when in the lateral decubitus position?
28. How should the patient’s legs be positioned when in the lateral decubitus position?
29. How should the patient’s nondependent arm be positioned when in the lateral decubitus position?
30. For what types of surgery is the sitting position most often used?
31. What are the cardiovascular effects of placing the patient in the sitting position for a surgical procedure?
32. What is the principal potential intraoperative complication of positioning a patient in the sitting position for surgery?
33. Which patients are most likely to manifest cardiopulmonary effects from being placed in the lithotomy position for a surgical procedure?
34. How should a patient with a history of low back pain be positioned in the lithotomy position for surgery?
35. What is the principal potential intraoperative complication of positioning a patient in the lithotomy position for surgery? How can this potential problem be minimized?
36. What is a potential problem that can result from placing a patient in the lithotomy position for more than 4 hours during a surgical procedure?
37. How can the patient’s digits of the fingers or toes be injured during moving of operating table parts?
Peripheral nerve injury
38. How important are peripheral nerve injuries? During what types of anesthetics do peripheral nerve injuries occur? What is the mechanism of a peripheral nerve injury during surgery? How can this risk be minimized?
39. What are some coexisting medical conditions that place a patient at an increased risk for a peripheral nerve injury?
40. What is the usual recovery time from a peripheral nerve injury?
41. Which peripheral nerve is most likely to manifest a postoperative neuropathy?
42. What are some ways in which the ulnar nerve may be injured intraoperatively? What position should a patient’s arm be placed in to minimize this risk?
43. Are males or females more prone to ulnar nerve injury during surgery?
44. How does injury to the ulnar nerve manifest clinically?
45. What is the second most common peripheral nerve injured during surgery?
46. Why is the brachial plexus especially susceptible to nerve injury during surgery?
47. What are some ways in which the brachial plexus may be injured intraoperatively?
48. How does injury to the brachial plexus manifest clinically?
49. What are some ways in which the radial nerve may be injured intraoperatively?
50. How does injury to the radial nerve manifest clinically?
51. What are some ways in which the median nerve may be injured intraoperatively?
52. How does injury to the median nerve manifest clinically?
53. What are some ways in which the sciatic nerve may be injured intraoperatively?
54. How does injury to the sciatic nerve manifest clinically?
55. Which peripheral nerve of the lower extremity is most likely to manifest a postoperative neuropathy?
56. What are some ways in which the common peroneal nerve may be injured intraoperatively?
57. How does injury to the common peroneal nerve manifest clinically?
58. What are some ways in which the anterior tibial nerve may be injured intraoperatively?
59. How does injury to the anterior tibial nerve manifest clinically?
60. What are some ways in which the femoral nerve may be injured intraoperatively?
61. How does injury to the femoral nerve manifest clinically?
62. What are some ways in which the saphenous nerve may be injured intraoperatively?
63. What are some ways in which the obturator nerve may be injured intraoperatively?
64. How does injury to the obturator nerve manifest clinically?
65. Can the intraoperative use of a tourniquet result in nerve injury?
Answers*
1. The position the patient is placed in intraoperatively while under general anesthesia is the responsibility of the anesthesiologist, surgeon, and nurses. The responsibility is shared among these operating room personnel. During the course of surgery the responsibility becomes primarily that of the anesthesiologist, who must be aware of any changes in the patient’s position. (300)
2. An awake patient will typically respond to pain, numbness, or tingling associated with nerve injury. However, positions that would not be tolerated by an awake patient can be assumed for hours while under anesthesia care, especially when combined with drug-induced skeletal muscle relaxation. Therefore, the anesthesiologist must share responsibility for the proper positioning of the patient during anesthesia, for appropriate padding of the pressure points, and must be aware of potential injuries associated with various positions. A description of the positioning and padding should also be documented in the anesthesia record. (300)
3. Potential injuries to the patient that can be sustained during mask ventilation of the airway include damage to the facial nerve and necrosis to the bridge of the nose. Facial nerve injury can be caused by the face strap on the anesthetic mask compressing the buccal branch of the nerve or by the anesthesiologist’s fingers on the ascending ramus of the patient’s mandible. Both of these risks are rare, however.
4. Skin that is subject to excessive or prolonged pressure is at risk for ischemic damage. Areas of skin that are especially prone to ischemic damage during surgery include the heels, supraorbital ridge, and the skin at the corner of the mouth in contact with the endotracheal tube. The risk of skin ischemia can be minimized with adequate padding at potential pressure points.
