1. Surgical Positioning
Jeffrey Groom PhD, CRNA Nurse Anesthetist Program Florida International University

2. SURGICAL POSITIONING OBJECTIVES
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. Trendelenberg – Reverse Trendelenberg
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 Positioning OR Table Attachments

14. Surgical Positioning All positioning schemes have 3 goals:
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. What happens when the anesthetized patient can’t care for themselves?
Surgical Positioning
What happens when the anesthetized patient can’t care for themselves?
How is it specified in hospital policy?

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. Why is there a risk for injury ?
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. How do nerves get injured? Example
How do nerves get injured? Example

20. Nerve fiber

21. 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
claims for anesthesia-related nerve injuries
#1 - Ulnar nerve (28%)
#2 - Brachial plexus (20%)
#3 - Common peroneal (13%)
ASA closed claims database is a standardized collection of case summaries derived from the closed claims files of professional liability insurance companies.

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. Brachial Plexus Injury
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 Positioning Supine
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.
Place a small pillow or soft pad under small of back or under knees to maintain normal lumbar curvature

38. Surgical Positioning Supine (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.
Soft padding under the elbow
Avoid tight wristlets

39. Surgical Positioning Supine
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 Positioning Supine
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.
Use a soft pad or a donut to stabilize the head and occiput.

41. Surgical Positioning Supine
Use a soft pad or a donut to stabilize the head and occiput.

42. Surgical Positioning Prone
Use a soft pad or a donut to stabilize the head and occiput.

43. Surgical Positioning Prone
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 Positioning Prone
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 Positioning Prone
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
Diaphragm pushed cephalad
Anterior chest expansion
V/Q mismatches

46. Surgical Positioning Prone
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
TOS- compression of the brachial plexus and subclavian vessels near the first rib

47. Trendelenberg – Reverse Trendelenberg
Surgical Positioning
Trendelenberg – Reverse Trendelenberg

48. Surgical Positioning Trendelenburg
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 Positioning Reverse 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 Positioning Lateral Decubitus

51. Surgical Positioning Lateral Decubitus
Usually positioned with bean bag or position supports.
Head must be aligned to support the spinal column and prevent compression of dependent arm.
Pillows placed between legs and feet
Bottom leg flexed to provide stability and facilitate venous drainage.
Peroneal nerve susceptible to injury
Leaves the posterior aspect of the knee and wraps around the head of the fibula

52. Surgical Positioning Lateral Decubitus
Presents anesthetic challenges-
Compression of vena cava with kidney rest
Dependent lung is underventilated-pressure of abdominal contents and wt of mediastinum.
Nondependent lung is overventilated because of increased compliance.
Blood flows to underventilated lung by gravity.
V/Q mismatch may manifest as hypoxemia

53. Surgical Positioning Lateral Decubitus
Kidney rest- beneath the bony iliac crest, not under fleshy waist area
Axillary rolls- placed at scapula near the axillary space to relieve pressure on the arm and foster adequate chest excursion.
Dependent shoulder, axilla, and deltoid must be padded.
Lower arm brought forward to prevent pressure on brachial plexus.
Chest surgery- upper arm flexed at elbow and raised above head to elevate scaplua and widen intercostal spaces.

54. Surgical Positioning Lateral Decubitus
Cardiac
Output unchanged unless venous return obstructed (kidney rest).
May see decrease in arterial blood pressure as a result of decreased vascular resistance (R > L).
Respiratory
Decreased volume and increased perfusion of dependant lung, V/Q mismatch potential

55. Surgical Positioning
Sitting – Beach Chair

56. Surgical Positioning Sitting
Cardiac
Pooling blood in lower body decreases central blood volume.
ABP fall despite increase in HR & SVR. (30%)
C.O. decreases 20-40%
Increase in sympathetic /parasympathetic tone
Intrathoracic blood volume decreases as much as 500 ml
Respiratory
Lung volumes are increased.
FRC is increased.
Work of breathing is decreased.

57. Surgical Positioning Sitting
Posterior Foss Craniotomy & shoulder procedures.
Full sitting position is uncommon.
Lounge chair, beach chair.
Facilitates venous drainage.
Venous air embolism risk is potential hazard

58. Surgical Positioning Sitting
Complications
Postural hypotension
Air emboli
Potentially lethal
Chances increase with degree of elevation of op site.
Dx: change in heart rate, murmur, decreased in exp CO2, cardiac dysrythmias, change in heart sounds generated by a parasternal Dopppler.
TEE most sensitive for detection (0.015 ml/kg/air)
Gasp breath may be first indicator
Decreased Pa02, etCO2, increased etN

59. Surgical Positioning Sitting
Complications
Ocular compression
Pneumocephalus
Edema of face, head, and neck due to prolonged neck flexion resulting in venous and lymphatic obstruction.
Sciatic nerve injury
Bended knees without flexion of the hips
Foot drop is clinical manifestation

60. Surgical Positioning
Lithotomy

61. Surgical Positioning Lithotomy
Cephalad displacement of the diaphragm.
Principle hazards:
Common peroneal- foot drop
Femoral- decreased or absent knee jerk
Saphenous-
Obturator-inability to adduct leg & diminished sensation over medial side of the thigh
Sciatic nerve- weakness of all skeletal muscles below the knee
Both legs should be elevated & flexed at same time to avoid stretching of peripheral nerves
Thighs should be no more than 90o
CP is branch of sciatic nerve

62. AANA Scope and Standards for Nurse Anesthesia Practice Standard V
Nurse anesthetists should “monitor and assess patient positioning and protective measures at frequent intervals.”
Failure to follow professional standards and guidelines may result in positioning injuries and liability.

63. Pommier vs Savoy Memorial Hospital
LIABILITY EXAMPLES
Pommier vs Savoy Memorial Hospital
55 y.o female w/fractured hip
2hr 20 min surgery
Developed peroneal palsy post-op
Plaintiff unaware of what actually happened during operation and no direct evidence of negligence, but she didn’t have the injury prior to surgical procedure. If injury occurs you assume negligence.
Warning for crna’s to understand their responsibility for padding and positioning the patient and thoroughly documenting that the pt had been carefully positioned, padded, and monitored.
Not a common injury for ortho procedures LA
Improper documentation re: padding
Hospital policy- entire OR team responsible
Protective and monitoring measures were not taken nor documented. No prior injury present. Conclusion at trial – injury would not have occurred had there not been negligence – res ipsa loquitur.

64. Shahine vs. Louisiana State University Medical Center, 680 So
Shahine vs. Louisiana State University Medical Center, 680 So. 2d 1352 (La. App., 1996)
"#6 table with safety strap in place 2" above knees - supine with bean bag underneath patient post induction & catheter insertion into the left side, with right side up, per __M.D. & __M.D, - auxiliary roll in place (1000cc bag IV fluid wrapped in muslin cover) - held in place per surgeons until bean bag deflated with suction - pillow placed under right leg with left leg bent slightly - U drape in place per surgeons pre prep - left arm extended on padded arm board - right arm placed on mayo tray that is padded."
Protective and monitoring measures were taken and documented. Brachial plexus injury reported postop. No prior injury present. Conclusion at trial – injury was a risk of the procedure however personnel took precautions according to standards and were not negligent.

65. ASA Practice Advisory – Sets a legal standard of care LINK to Advisory in the Course Outline Page

66. Upper extremity positioning
Arm abduction should be limited to 90° in supine patients; patients who are positioned prone may tolerate arm abduction greater than 90°
Arms should be positioned to decrease pressure on the postcondylar groove of the humerus (ulnar groove).
When arms are tucked at the side, a neutral forearm position is recommended. When arms are abducted on armboards, either supination or a neutral forearm position is acceptable
Prolonged pressure on the radial nerve in the spiral groove of the humerus should be avoided
Extension of the elbow beyond a comfortable range may stretch the median nerve

67. Lower extremity positioning
Lithotomy positions that stretch the hamstring muscle group beyond a comfortable range may stretch the sciatic nerve
Prolonged pressure on the peroneal nerve at the fibular head should be avoided
Neither extension nor flexion of the hip within normal range of motion increases the risk of femoral neuropathy

68. Protective padding
Padded armboards may decrease the risk of upper extremity neuropathy
The use of chest rolls in laterally positioned patients may decrease the risk of upper extremity neuropathies
Padding at the elbow and at the fibular head may decrease the risk of upper and lower extremity neuropathies, respectively
Equipment
Properly functioning automated blood pressure cuffs on the upper arms do not affect the risk of upper extremity neuropathies
Shoulder braces in steep head-down positions may increase the risk of brachial plexus neuropathies

69. Postoperative assessment
A simple postoperative assessment of extremity nerve function may lead to early recognition of peripheral neuropathies
Documentation
Charting specific positioning actions during the care of patients may result in improvements of care by (1) helping practitioners focus attention on relevant aspects of patient positioning; (2) providing information that continuous improvement processes can use to lead to refinements in patient care; and (3) provide medicolegal defense

70. Positioning Checklist
Surgical Positioning
Positioning Checklist

71. Positioning Checklist
Head, neck and cervical spine supported in a straight line.
Scalp, head, and face protected from tight anesthesia mask/straps.
Ears protected from traumatic pressure/objects.
Chest and torso kept in physiological position for adequate full, bilateral respiratory exchange and expansion.
Breasts & genitalia protected from excessive pressure.

72. 6. Arms in physiological position and supported
6. Arms in physiological position and supported. - not to exceed 90 degree extension at shoulder - in flexion not hyperextension - upper arm not hanging over edge of table or rubbing on metal part of table - elbow area protected from ulnar pressure - hands free of pressure and compression - fingers in slight flexion or neutral extension - wrist restraints loose or padded - palms up on armboard - palms towards body when arms at side

73. Positioning Checklist
Genitals free of trauma, pressure, or rubbing.
Back in physiological position, spine in straight line
- slight sacral curvature
- soft small positioning devices under sacral area and knees to relieve
pressure, pain, or stretching.
Thighs/legs in straight line of flexed position; no pressure to iliac crests, greater trochanters, area bt back & knees, peroneal nerve on lateral aspects of knees, or to patellas.
Heels/ankles/toes free of pressure or rubbing trauma.
Safety belt placed snugly over patient w/blanket or towel between strap and patient’s body to prevent maceration.
Other straps or positioning devices placed only over padded body parts.

74. Surgical Positioning
During clinical this semester – spend time after cases learning the operation of the OR table and proper positioning. Practice on each other to appreciate “positioning” from patient’s perspective.