Surgical Positioning

1. 0 Surgical Positioning Jeffrey Groom PhD, CRNANurse Anesthetist ProgramFlorida International University

2. SURGICAL POSITIONINGOBJECTIVES • Identify the role and responsibility of the anesthesia provider in patient positioning. • Describe the complications associated with improper patient positioning. • Describe the physiological changes that occur with the various positions. • Identify scenarios involving medicolegal liability associated with improper patient positioning.

3. Surgical table

4. Surgical Positioning SUPINE

5. Surgical Positioning Trendelenberg – Reverse Trendelenberg

6. Surgical Positioning Lateral Tilt

7. Surgical Positioning Lithotomy

8. Surgical Positioning Sitting – Beach Chair

9. Surgical Positioning JackKnife - Kneeling

10. Surgical Positioning

12. Surgical Positioning

13. Surgical PositioningOR Table Attachments

14. 0 Surgical Positioning • All positioning schemes have 3 goals: • 1. Maximum exposure to the surgical area while maintaining homeostasis and preventing injury • 2. Position must provide the Anesthetist with adequate access to the patient for airway management, ventilation, medications, and monitoring • 3. Promote the enhancement of a satisfactory surgical result

15. 0 What happens when the anesthetized patient can’t care for themselves? Surgical Positioning

16. Surgical Positioning When you sleep, you reposition yourself to prevent pressure ischemia. Under anesthesia, the patient does not reposition (protect) them self so the responsibility falls to the surgical team to prevent pressure ischemia & positioning injuries.

17. Surgical Positioning Why is there a risk for injury ? • Positioning and Anesthesia • Blunted or obtunded reflexes prevent patients from repositioning themselves for relief of discomfort • Anesthesia may blunt compensatory sympathetic nervous system reflexes that would minimize systemic BP changes with abrupt position changes • Rendering patients unconscious and relaxed may permit placement in position they may not have normally tolerated in an awake state

18. Patient Injury and Surgical Positioning • Most are nerve injuries due to overstretching and/or compression. • 90% undergo complete recovery. • 10% are left with residual weakness or sensory loss. • Many injuries can produce lasting disability. • Many injuries lead to litigation. • General anesthesia removes many of the bodies natural protective mechanisms. • Recognition of risks and prevention is essential.

19. 0 How do nerves get injured? Example

20. Nerve fiber

21. 0 Peripheral Nerves from Spinal Cord • only sensory fibers run in the dorsal root • motor fibers (somatic and autonomic) leave the cord via the ventral roots • sympathetic fibers leave the cord via ventral roots from T1 - L2

22. Peripheral Nerve Injury

23. Preoperative History and Physical Assessment Preexisting patient attributes associated with increased incidence of perioperative neuropathies: • extremes of age or body weight, • preexisting neurologic symptoms, • diabetes mellitus, • peripheral vascular disease, • alcohol dependency, • smoking, • and arthritis.

24. Surgical Positioning ASA Closed Claims • 1999 - 670 claims for anesthesia-related nerve injuries • #1 - Ulnar nerve (28%) • #2 - Brachial plexus (20%) • #3 - Common peroneal (13%)

25. Surgical Positioning Ulnar nerve injury • Caused by arms along side patient in pronation • Ulnar nerve compressed at elbow between table and medial epicondyle. • Prevented by positioning arms in supination. • Hypotension and hypoperfuison increase risk.

26. Ulnar Nerve

27. Yo s’up dude?

28. Surgical Positioning Brachial Plexus Injury • Excessive arm abduction or external rotation. • Prevented by avoiding more than 90o abduction. • Secure arm to prevent arm from falling off of table or arm board.

29. Brachial Plexus

30. Surgical Positioning Brachial Plexus • Abduct arms to no more than 90 degrees. • Minimize simultaneous abduction, external arm rotation, and opposite lateral head rotation. • In prone position, maintain abduction and anterior flexion of arms above head to no more than 90 degrees. • In lateral position, place chest roll under lateral thorax to minimize compression of humerus into axilla.

31. Brachial Plexus

32. Surgical Positioning Peroneal nerve • Caused by direct pressure on the nerve with the legs in lithotomy position. • Nerve compressed against neck of fibula. • Prevented by adequate padding of lithotomy poles.

33. Surgical Positioning

34. Surgical Positioning

35. Surgical Positions and Anesthesia Implications

36. Surgical Positioning SUPINE

37. Surgical PositioningSupine • Most frequently used position. • Cervical, thoracic, lumbar vertebrae should be in a straight, horizontal line. • Minimal effects on circulation. • FRC decreases 25-30% from upright. • Arm boards and arm must be less than 90o abduction angle to the torso.

38. Surgical PositioningSupine (con't) • Arms at greater than 90o angle results in stretch of the subclavian and axillary vessels resulting in radial pulse obliteration and arterial thrombosis. • Injuries have been reported with as little as 60o abduction. • Palms up- relieves pressure on the ulnar nerve as it passes through the humeral notch at the elbow.

39. Surgical PositioningSupine • Ulnar nerve injury • Hypotension and hypoperfusion increase risk • Inability to abduct or oppose the 5th finger • Atrophy of the intrinsic muscles of the hand (claw hand).

40. Surgical PositioningSupine • Extreme rotation of the head can cause occlusion and thrombosis of the vertebral artery. • Pressure from a mask or head strap can cause injuries of the supraorbital and facial nerves. • Relaxation of the paraspinous muscles and flattening of the normal lumbar convexity results in tension on the interlumbar and lumbosacral ligaments causing a backache.

41. Surgical PositioningSupine

42. 0 Surgical PositioningProne

43. Surgical PositioningProne • Induction completed on stretcher, then patient logrolled to OR table under command of CRNA • Body ‘logrolled’ as a unit in a smooth, slow, and gentle manner. • Neck in alignment with spinal column. • Eyes and ears protected and not depressed. • Chest rolls, or bolsters are placed lengthwise on both sides of the thorax, extending from the acromioclavicular joints to iliac crest-adequate lung expansion and diaphragm excursion.

44. Surgical PositioningProne • Protect female breasts & male genitalia. • Pillow under legs & ankles to flex knees and prevent pressure on toes and plantar flexion of feet. • Arms at side or extended alongside the head on arm boards • Documentation: pressure points padded, free abdominal and chest expansion, position of the arms, eye care

45. Surgical PositioningProne • Cardiac • Pooling of blood in extremities • Compression of abdominal muscles • Decrease preload, c.o., and blood pressure • Increased SVR and PVR • Decreased stroke volume and cardiac index • TEDS or pneumatic sequential compression stockings to minimize pooling of blood

46. Surgical PositioningProne • Respiratory • Decreased lung compliance • Increased work of breathing • Thoracic Outlet Syndrome-secondary to thoracic nerve compression (agonizing, debilitating, and unremitting pain post-operatively following overhead arm placement • ETT dislodgement - Extubation

47. Surgical Positioning Trendelenberg – Reverse Trendelenberg

48. Surgical PositioningTrendelenburg • Cardiac • Activation of baroreceptors • Decrease in C.O., PVR, HR, and BP • Does not improve C.O. in hypotension & hypovolemia • Respiratory • Decreased FRC, total lung capacity and pulmonary compliance secondary to shift of abdominal viscera • Increased V/Q mismatching • Atlectasis • Increased likelihood of regurgitation • Use of shoulder braces to prevent cephalad mvmt

49. Surgical PositioningReverse Trendelenburg • Cardiac • Decrease in c.o., preload, and arterial pressure • Baroreflexes increase sympathetic tone, HR , PVR. • Respiratory • Work of breathing decreased • Increase in FRC

50. Surgical PositioningLateral Decubitus