2. Introduction
Positioning of the patient for intracranial procedures
remains a critical step in a successful surgery.
Term positioning refers to the position of the surgeon as
well as that of the patient.
Some surgeons prefer to sit and some prefer to stand.
3. AIM:
To reduce or eliminate the need for brain retraction.
Helps in providing a clear and bloodless field.
Reduce intracranial pressure and avoid venous obstruction.
Minimize the chance of avoidable complications such as
brachial plexus stretch injuries and pressure neuropathies.
4. Head Positioning
Head can be positioned on the horseshoe headrest (or
doughnut).
During positioning, the head can be safely rotated between
0 – 45 degrees away from the body.
If more rotation is needed, a roll or pillow placement
under the opposite shoulder is recommended.
8. Maintaining 2–3 finger-breadths thyromental distance is
recommended during neck flexion.
Hyperflexion, hyperextension, lateral flexion or rotation should
be avoided.
9. Fixation of the Head
Head is fixed with the three or four-pin fixation device.
Application of a skeletal fixation device /tightening of pins -
profound tachycardia and hypertension-
Rupture of untreated cerebral aneurysms
Local infiltration of the skin anesthesia should be deepened.
12. Supine Position(Dorsal Decubitus Position)
Simplest ,versatile.
Does not require special instrumentation, is easily
achievable, and usually does not require disconnection of
the tracheal tube and invasive monitors.
13. HEAD DURING SUPINE POSITION
Neutral or rotated → frontal, temporal or parietal access.
Neutral → Bifrontal craniotomy
Flexion → interhemispheric approach to lateral or third
ventricle.
Slight extension → subfrontal approach.
14. ARM POSITION
Arm position using the arm board.
Abduction of arm is limited to < 900. Arm
is supinated and elbow is padded.
Arm tucked at patient side and is in
neutral position with palm to hip. Elbow
is padded and arm is well supported by
the mattress.
15.
16. supine positioning
Horizontal position .
Lawn chair (contoured) position.
Head-up tilt or reverse Trendelenberg position .
17.
18. LAWN CHAIR POSITION
Advantages:
Promotes cerebral venous drainage
Decreases stress on back, hips and knees.
Venous return from lower extremity improves (legs are slightly
above heart level).
FLEXION + PILLOW UNDER KNEES + SLIGHT REV. TRENDELENBERG
20. REVERSE TRENDELENBURG POSITION
Also known as ‘head-up tilt’.
Precautions -
Preventing the patients from slipping on the table.
Frequent monitoring of arterial blood pressure → hypotension may
result from ↓ VR.
Head is positioned above heart → ↓ perfusion pressure to brain.
Complications –
1. Hypotension
2. ↑Venous air embolism
21. PRECAUTIONS
Extremes of head rotation- impairs jugular venous drainage.
Extreme flexion causes kinking of ET tube → ↑airway pressures
(keep a distance of 1 or 2 finger breadths between chin & chest
during flexion).
22. COMPLICATIONS OF SUPINE
POSITION
1. Pressure alopecia -
Cause –
Ischemia of hair follicles due to prolonged head immobilization with its full
weight falling on a limited area (usually occiput).
2. Backache -
Cause –
Normal lumbar lordotic curvature is lost during general anaesthesia
with muscle relaxation due to their effects on tone of paraspinous
muscles.
3. Peripheral nerve injury –
Ulnar neuropathy is most common.
4. ↑ risk of aspiration of gastric contents.
23. BRACHIAL PLEXUS INJURY
Brachial plexus (primarily C8
and T1 nerve roots)
susceptible to injury
because:-
Long superficial course via
axilla with 2 points of fixation
- cervical vertebrae and
axillary fascia.
Lies in close proximity to
relatively fixed first rib,
clavicle and humerus and get
compressed between these
structures.
Precautions –
Arm abduction limited < 900
Avoid shoulder braces
Head in midline
24.
25. SEMILATERAL /
JANETTA
POSITION *Supine position with a bolster
Lateral tilting of the table, 10-20⁰ with I/L shoulder
elevated
For petrosal, retromastoid & U/L frontotemporal
approaches
26.
27. Prone position
FOR access to - occipital lobes, midline or paramedian
cerebellum, pineal region, fourth ventricle, and upper cervical
spine
28. 1
• When general anaesthesia is planned, all intravenous
accesses are obtained & trolley is kept parallel and
adjacent to operating table.
2
• Patient is first intubated on the stretcher.
3
• ETT is well secured to prevent dislodgement and loosening
of tape due to drainage of saliva when prone.
• Antisialogogue (glycopyrrolate)
POSITIONING
29. 4
• 2 assistants stand on free side of table & another 2 on
free side of trolley. One manage feet
5
• Neck is kept in line with spine during proning & arms of
the patient kept alongside the body.
6
• If cervical spine is stable, anaesthetist manage head &
coordinate turn; if unstable neurosurgeon.
POSITIONING
30. 7
• Disconnecting BP cuffs, arterial and venous lines is
recommended to avoid dislodgment.
8
• Pulse oximetry can usually be maintained if applied
to the inside arm.
9
• Full monitoring should be reinstituted as rapidly as
possible.
POSITIONING
31. POSITIONING
10
• ET tube position and adequate ventilation
immediately reassessed after the move.
11
• Legs should be padded and flexed slightly at the
knees and hips.
12
• Head may be supported facedown with its weight
borne by the bony structures or turned to the side.
32. HEAD POSITION
Head is kept in neutral position (most common) using → a) Surgical
pillow, b) Horseshoe headrest or c) Mayfield head pins.
Disadvantage with pillows → face is not always visible.
Mirror systems are available to facilitate intermittent visual
confirmation that eyes are not compressed.
33. Horseshoe headrest supports only forehead and malar regions and allows
excellent access to the airway.
Mayfield rigid pins firmly hold the head in one position without any direct
pressure on face & allow access to the airway.
HEAD POSITION
Mirror system for prone position Prone position with horseshoe adapter
36. ARMS POSITION
Both arms may be kept along the patient’s sides and tucked in
neutral position or placed in the “stick-em up” position.
In ‘stick-em up’ position, arms should not be abducted > 90⁰ &
elbows should not be extended > 90⁰ (90-90 position) to prevent
excessive stretching of brachial plexus, especially in patients with
head turned.
Extra padding under the elbow may be needed to prevent
compression of ulnar nerve.
39. TAKE CARE OF ABDOMEN & THORAX
External pressure on abdomen → ↑intra-abdominal and intra-thoracic
pressures.
↑Abdominal pressure → ↑venous pressure of valveless abdominal &
spine vessels (including epidural veins) and causes compression of IVC
→↓VR, cardiac output.
External pressure on abdomen pushes diaphragm cephalad → ↓FRC &
pulmonary compliance.
Firm rolls or bolsters placed along each side from clavicle to iliac crest to
support the torso → ↓abdominal, thoracic pressures.
40. PRECAUTIONS
Dependent eye must be frequently checked for external
compression.
Abdomen should hang relatively free and move with respiration.
Breasts should be placed medial to gel bolsters.
41. CONCORDE POSITION modification of the prone position. This is the best
positioning for surgical approach to occipital transtentorial and supracerebellar
infratentorial
area. The body is positioned in reverse Trendelenburg and chest rolls are placed under
the trunk.
The arms are tucked alongside to the trunk, and the knees are flexed
42. 1. Postoperative vision loss (POVL) –
Retinal ischemia Ischemic optic neuropathy (ION) (more common)
2. Macroglossia –
Flexion of neck → ↓AP dimension of hypopharynx → compression ischemia of
tongue base, soft palate, posterior wall of pharynx occur in presence of foreign
bodies (ETT)
Edema accumulates after reperfusion of ischemic tissue → Macroglossia → post-
extubation airway obstruction.
COMPLICATIONS
44. Modification of prone .
Far lateral approach .
occipital transtentorial approach to access pineal and tentorial region tumors, CPA
tumors/ MVD (CN -V).
Small axillary roll is placed -inferior or ipsilateral axilla.
Ipsilateral or inferior arm is placed behind the body.
The superior or contralateral arm should be placed against the patient's side in a neutral
position
45. PARK-BENCH OR
THREE QUARTER PRONE POSITION
Modification of prone position.
Provides better access to posterior fossa (compared to lateral position).
Placing patient sufficiently superiorly on operating table such that
dependent arm hangs over edge of table & secured with a sling.
Trunk is rotated 15⁰ from lateral position into semiprone position &
supported with pillows.
Lower extremities should be slightly flexed and pillow placed between legs.
Head is flexed at neck and then rotated to look toward the floor (120⁰ from
vertical & laterally flexed 20⁰ ).
46.
47.
48. Lateral Position
Temporal
craniotomy .
middle cranial
fossa
CPA and lateral
cerebellum.
for far/extreme
lateral
approaches to
access lesions of
the pineal region,
posteriorfossa
49. ARM POSITION
Dependent arm rests on a padded arm board perpendicular to the
torso.
Non-dependent arm is supported over armrest or neutral position.
Neither arm should be abducted > 900.
Axillary roll is placed between chest wall and bed just caudal to
dependent axilla to prevent compression of dependent
neurovascular bundle (should never be placed in the axilla).
50.
51.
52. Axillary roll is placed well away from
axilla to prevent compression of axillary
artery and brachial plexus.
53. PHYSIOLOGICAL CHANGES
Respiratory system:-
Non-dependent lung → well ventilated, poorly perfused.
&
Dependent lung → well perfused, poorly ventilated (due to lateral
weight of mediatinum & disproportionate cephalad displacement of
abdominal contents)
↑ V/Q mismatch
54. Risks with Lateral Position
• Brachial plexus injuries
• stretch injuries to other nerves
• ventilation-perfusion mismatch
55.
56. INTRODUCTION
Used for posterior cervical spine and posterior fossa surgeries.
Infrequently used.
Advantages –
Excellent surgical exposure
Dry field
↓Perioperative blood loss
Superior access to the airway
↓Facial swelling
58. SEQUENCE
Raise the back further untill the desired sitting
position is achieved
Finally adjust foot section of the table to horizontal
position
59.
60.
61.
62. POSITIONING
Head may be fixed in Mayfield head pins.
Head holder should be attached to back portion of the table, rather
than to the thigh or leg portions → makes lowering of head, easier.
Arms must be supported.
63. Patient is typically semi-
recumbent rather than sitting.
A –
The head-holder support is
correctly positioned so that
the head can be lowered
without the necessity to first
detach the head holder.
B –
This configuration with the
support attached to the
thigh portion of the table,
should be avoided.
65. Legs should be kept as high as possible (usually with pillows under
knees) to promote venous return.
Knees are slightly flexed for balance and to reduce stretching of
sciatic nerve.
Feet are supported and padded.
Elastic stockings and active leg compression devices also help to
maintain venous return.
POSITIONING
69. Air embolism….management.
Flood with irrigating solution
Wax -cut ends of bones
Coagulate open veins
Wound pack with gauze
Left lateral recumbent position right up
Aspirate air, avoid nitrous oxide.
cardiovascular support with administration of inotrope
