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4 Fundamentals ofPatient Positioning andSkin Prep
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67
a
b
Fig. 4.1 Ulnar nerve injury. (a) Potentially nerve threatening position. (b) Correct positioning (taken from web)
that may result in foot drop and loss of sensation
over the lateral aspect of the leg and dorsum of
the foot [3] (Fig.4.3).
Up to 15% of lower limb peripheral nerve
nerve. Clinical symptoms of femoral nerve injury
are sensory loss along the area covered by the
anterior and lateral femoral cutaneous nerves and
will resolve spontaneously in 94% of the cases.
injuries are related to the sciatic nerve, especially
with hyperexion of the hip and extension of the
knee in exaggerated lithotomy position. This will
result in loss of extension and exion of the foot
and decreased sensation along the anterior and
posterior aspects of the leg and foot.
Femoral neuropathy comprises 4% of the
cases and is usually caused by continuous compression from intraabdominal retractors on iliopsoas muscle and external iliac artery, resulting
in ischemic or mechanical damage to the femoral
4.2.2.4 Pressure Ulcers
According to the Agency for Healthcare Research
and Quality, 2.5 million patients are affected by
pressure ulcers every year, of which 60,000 die
from direct consequences.
The surgical patient is more vulnerable to
pressure effect because the anesthesia itself
induces vasodilation that leads to a decrease in
blood pressure and perfusion. In addition, the
typically cooler operating room environment,
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Fig. 4.2 Brachial plexus injuries. (a)
Incorrect extension of the arm board more
than 90°. (b) Correct position of the arm
board. (c) Inadequate arm padding
resulting in a sagging arm board. The
dorsal extension of the arm stretches the
brachial plexus. (d) Correct leveling and
padding of the arm board to minimize
brachial plexus stretch and ulnar nerve
compression at the wrist (taken from web).
From Winfree CJ, Kline
DG.Intraoperative positioning nerve
injuries. Surg Neurol. 2005
Jan;63(1):5- 18; discussion 18. Review.
Figs.1 and 2 page 8. Permission not
requested
G. Giambartolomei et al.
More than
90 degrees
a
b
90 degrees
c
d
ner
Tibia
Skin
Pressure
4 Fundamentals ofPatient Positioning andSkin Prep
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69
and the use of vasopressors and diuretics, may
result in additional decrease in tissue perfusion.
It has been shown that a pressure greater than
32mmHg, which is the capillary lling pressure,
Common
peroneal
ve injury
Fibula
will result in occlusion of blood ow and tissue
ischemia. Skin and underlying tissues can tolerate high pressure for short amount of time and
low pressures for prolonged time, so that the surgical patient is predisposed to develop ischemic
injuries anyway. The duration of pressure over
2h is associated with an increased risk of development of pressure ulcers [7]. These occur more
likely over bony prominences covered by skin
and small amounts of muscles and subcutaneous
tissue (Fig.4.4).
Identied risk factors associated with the
development of perioperative pressure ulcers can
be divided into intrinsic or patient-related, extrinsic, and operating room related.
Patient-related risk factors comprise of the
ability to maintain an adequate tissue perfusion.
These factors include malnutrition (serum albumin ≤3g/dl), older age, ASA score ≥3, decreased
mental status, immobility, infection, incontinence, impaired sensory perceptions, and comorbidities such as diabetes, peripheral vascular
disease, pulmonary disease, BMI, and altered
hemodynamic status.
Extrinsic and operating room-related factors
include the type of anesthesia, use of vasopressors, length of surgery, room temperature, type of
table and pads, positioning and warming devices,
retractors, intraoperative blood pressure uctuations, and all the factors that affect shear forces,
moisture, and friction. The most meaningful risk
Fig. 4.3 Common peroneal nerve injury (taken from web)
Fig. 4.4 Pressure
exerted over bony
prominences
Epidermis
Subcutaneous
Deep fascia
Periosteum
Dermis
fat
Muscle
Bone
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G. Giambartolomei et al.
factor is the duration of the procedure, with
increased risk of developing pressure ulcers after
2.5–3h.
Rhabdomyolysis is a syndrome caused by
crush injury to the skeletal muscles that might
occur intraoperatively. The mechanism is related
to an ischemia-reperfusion syndrome that compromises sarcolemmal membrane integrity.
Skeletal muscle is able to tolerate up to 2 h of
ischemia with a complete recovery, but the
inammatory response that follows the reperfusion may be more detrimental for the evolution of
the syndrome, due to its increase in capillary permeability, delivery of oxygen-derived free radicals leading to sarcolemmal disruption, and
spreading into circulation of intracellular components like myoglobin and potassium ions [8]. The
resulting syndrome is characterized by hyperkalemia, hypocalcemia, and high serum creatine
kinase (CK), which might lead to acute renal failure, severe arrhythmias, and disseminated intravascular coagulation. Clinical presentation could
vary from numbness to pain and motor decit of
the interested area and dark urine. The extended
lithotomy position is mostly involved in this type
of complication, followed by lateral decubitus
position. Obese patients are at particularly high
risk for developing this syndrome.
4.3 Technical/Practical
Considerations/Safety
Precautions
4.3.1 Patient Positioning
The goals of a correct patient positioning can be
summarized as follows: ensuring optimal surgical exposure while protecting anatomical structures and ensuring patient comfort and dignity.
This must be accomplished while still guaranteeing adequate access for the anesthesia team
to the airway and to intravenous medication
administration.
It is therefore preferable to ensure a comfort-
able position to the patient when he/she is still
conscious.
4.3.2 Basic Positions
Every surgical subspecialty requires a different
position in order to provide ideal exposure of the
surgical site. Also, every surgeon might adjust the
basic position according to his/her technical needs.
4.3.3 Supine
This position is widely applied in surgical procedures, including abdominal surgery, urology,
orthopedic surgery, otorhinolaryngology, and
plastic surgery or whenever the surgical site is
located on the anterior aspect of the body.
The operative table is horizontally at; the
patient lies on his/her back, hips and knees
extended and arms positioned along the trunk or
abducted on arm boards. If the arms are positioned along the patient’s sides, the palm should
be facing the thigh; if placed on arm board,
proper padding should be provided together with
supination and slight exion in order to minimize
ulnar nerve compression injuries (Fig.4.5).
The pressure points more susceptible to potential injury are the occiput, the spinous processes
of the thoracic vertebrae, the sacrum and coccyx,
the scapulae, the olecranon, and the calcaneae. It
is a standard practice to use pink foam and pads
to protect these pressure points. The routine use
of such adjuncts should be included in the surgical checklist.
Abduction of an arm could make an access to
IVs and peripheral veins for the administration of
drugs and blood draws easier for the anesthesiologist. However, this position could result in less
work-space for the surgeon, especially if there is
reduced range of motion of the patient’s shoulder.
Moreover, extra care must be taken not to hyperextend the upper limbs more than 90° from the
trunk (Fig.4.2). Also, the arm boards should be
at the same height of the table, in order to avoid
brachial plexus injuries. Brachial plexus injuries
are extensively reported as a complication due to
malpositioning of the patient and can potentially
be irreversible depending on the mechanism of
nerve injury, as previously described.
4 Fundamentals ofPatient Positioning andSkin Prep
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Fig. 4.5 Supine position (taken from web)
71
The patient must be thoroughly secured to the
table with restraining straps or belts, surrounding
the thighs, the arms, and sometimes the chest.
These precautions are necessary to ensure stability of the patient even in steep positions (such as
the head-down tilt (Trendelenburg), and the head up tilt (reverse Trendelenburg) without exerting
excessive pressure on the limbs that might impair
blood ow or stretching injuries to the brachial
plexus. Securing the patient at the wrist level is
then contraindicated (Fig. 4.6). This is particularly important for obese patients, as the weight
shifts can cause compression injuries, limbs to
falls from table and arm board, and even torso to
fall from the operating table. For steep reverse
Trendelenburg position, foot plates can be utilized to prevent patients from sliding (Fig.4.7).
However, careful foot padding and knee alignment are paramount to prevent compression
injuries.
These principles are particularly important in
laparoscopic surgery. In fact, because of the
reduced ability of retraction, the exposure of the
operative eld is often achieved by the use of
gravity of steep table tilts. Vacuum beanbags can
be utilized as an adjunct to improve patient stability on the operating room table. It is important
to avoid direct contact of the beanbag to the
patient’s skin, in order to avoid skin burns and
lacerations. The use of shoulder braces during
steep head-down tilt positions could result in
potential compression of the brachial plexus.
Hence, when used they should be well padded
and away from the neck. Finally, in head-up tilt
positions, a footboard can be used, after providing optimal padding to the heels.
4.3.4 Lateral
This position is usually used in neurosurgery,
thoracotomies, and total hip replacement, as well
as in urology and vascular surgery when retroperitoneal structures are approached directly. In
general surgery this position is utilized for the
laparoscopic approach to the spleen and adrenal
gland.
The patient is usually transferred from a
supine to a lateral position when secure endotracheal anesthesia has been already established.
During the rolling maneuver, a correct spinal
alignment should be maintained, and shearing
and friction injuries should be avoided. A pillow
or headring should be placed to support the head
and maintain correct alignment with the neck and
the rest of the body.
The patient lies on one side, usually at 90°
angle between the patient’s back and the table.
The lower limb resting on the table should be
exed with an angle of 90° between the thigh and
the leg, while the other lower limb should be
extended. A pillow should be placed between the
legs to prevent damage to peroneal and saphenous nerves.
To protect the axillary nerve bundle and artery
of the arm resting on the table, an axillary roll
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Fig. 4.6 A Trendelenburg position with the patient
secured at the wrists determines a downward pull of the
humerus head and stretching injury of the brachial plexus.
From Cooper DE, Jenkins RS, Bready L, Rockwood CA Jr.
Fig. 4.7 Adjustable foot
plate for reverse
Trendelenburg positions.
From the web
The prevention of injuries of the brachial plexus secondary to malposition of the patient during surgery. Clin
Orthop Relat Res. 1988 Mar;(228):33-41. Fig.5-A page
37. Permission not requested
4 Fundamentals ofPatient Positioning andSkin Prep
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Fig. 4.8 Lateral decubitus position (taken from web)
73
should be positioned just under the axilla to
relieve direct lateral pressure on the shoulder and
avoid perfusion impairment. However, there are
few old reports of complications of axillary rolls
secondary also to compression of the axillary
vessels, nerves, and even bronchus (“axillary”
compression syndrome) [9]. For this reason,
some authors suggest to use a rubber foam under
the upper chest just inferior to the tip of the scapula, instead of an axillary roll. It is also advisable
to check the radial pulse of the dependent arm to
conrm a proper perfusion.
The upper arm should be kept horizontal by
the use of a pillow or by an arm board. The horizontal position of the arm will also allow for a
more reliable and precise blood pressure measurements. The palm of the inferior hand is positioned upward, and the palm of the superior hand
is positioned downward.
Proper padding should be provided to pressure
points such as the downside ear, the acromion
process, the olecranon, the rib cage, the iliac
crest, the greater trochanter, the medial and lateral condyles of the knee, and the medial and lateral malleoli (Fig.4.8).
4.3.5 Lithotomy
This position is widely used in gynecological,
urological, and colorectal/proctologic surgery, as
it provides direct access to the perineal area [10].
In the lithotomy position, the patient lies on
the back; inferior limbs are positioned on leg
holders, unforcedly abducted about 30–45° from
the midline; and thighs are exed over the hips
with an angle of about 80–100° on the trunk, with
the knees being exed until the legs are parallel to
the frontal plane of the torso (Figs.
4.9 and 4.10).
In order to prevent traction of the obturator nerve,
the leg should be abducted and aligned with the
contralateral shoulder (Fig.4.11).
The patient’s buttock should be positioned at
the edge of the lower table break, to reduce lordosis, and the external rotation of the hips should be
minimal (Figs.4.10 and 4.11). The legs and feet
should be positioned on stirrups with a popliteal
support and a calf rest, avoiding unnecessary
pressure points and minimizing movements
within the stirrups (Fig.
4.12). For this reason
stirrups with a foot and ankle support are preferred to decrease pressure on the calf (Fig.4.13).
Also appropriate padding should be provided to
the head of the bula to avoid common peroneal
injuries, excessive hip exion can stretch sciatic
and obturator nerves, and the femoral nerve can
be compressed under the inguinal ligament
(Fig.4.14). Legs should be raised simultaneously
and slowly to avoid a progressively increasing
venous return impairing cardiovascular function,
especially in poor heart-compliant patients. Also
when raising legs above heart level, peripheral
pulses should be checked because local ischemia
to neuromuscular structures can occur, resulting
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Fig. 4.9 Lithotomy position (taken from web)
Fig. 4.10 Correct position of the sacrum (from the
Prevention of Positioning Injuries during Gynecologic
Operations. Guideline of DGGG. M. C. Fleisch, D.
Bremerich, W. Schulte-Mattler, A. Tannen, A. T. Teichmann,
W. Bader, K. Balzer, S. P. Renner, T. Römer, S. Roth, F.
Schütz, M. Thill, H. Tinneberg, and K. ZarrasGeburtshilfe
Frauenheilkd. 2015 Aug; 75(8): 792–807. doi:
10.1055/s-0035-1557776). Permission not requested
in a compartment syndrome [9]. Similarly, at the
end of the procedure, legs should be simultaneously and slowly lowered to avoid spine torsion
and to allow the vessels to progressively rell
minimizing the risk of hypotension due to relative hypovolemia.
The upper limbs should be positioned on padded arm boards, abducted no more than 90°, or
over the abdomen. Placing the arms to the
patient’s side could result in nger injury when
the lower table section is elevated.
Critical pressure points in the lithotomy position
are the occiput, the spinous processes of the thoracic vertebrae, the sacrum, the medial and lateral
epicondyles, the olecranon, the scapulae, the femoral condyles, and the medial and lateral malleoli and
calcaneae, so proper padding should be provided.
4.3.6 Prone
The prone position is frequently used for surgical access to the posterior spine and thorax and
the posterior cranial fossa. Since the patient lies
4 Fundamentals ofPatient Positioning andSkin Prep
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on the ventral aspect of the torso, unfavorable
cardiorespiratory mechanics occurs. In fact,
abdominal compression causes an increase in
intraabdominal pressure that might lead to a
compression of the vena cava and ultimately in a
decrease in venous return and cardiac output.
Also epidural veins could be engorged and result
in increased surgical bleeding. It is therefore
mandatory to allow diaphragmatic excursion
using chest and pelvis support or using a specialized prone operating table (Jackson table).
Arms can be either raised beside the head on
padded arm boards or retained along the sides of
the body; when raised bedside the head, forearms
should be lower than the head to avoid brachial
plexus stretching (Fig.4.15).
Fig. 4.12 Avoid pressure to the popliteal fossa with the
ankle suspended (from the Prevention of Positioning
Injuries during Gynecologic Operations. Guideline of
DGGG.M. C.Fleisch, D.Bremerich, W.Schulte-Mattler,
A.Tannen, A.T. Teichmann, W. Bader, K. Balzer, S.P.
Renner, T. Römer, S. Roth, F. Schütz, M. Thill,
H. Tinneberg, and K. ZarrasGeburtshilfe Frauenheilkd.
2015 Aug; 75(8): 792–807. doi: 10.1055/s-0035-1557776).
Permission not requested
Fig. 4.11 Correct angulation and abduction of the lower
extremities to prevent traction of the obturator nerve
(from the Prevention of Positioning Injuries during
Gynecologic Operations. Guideline of DGGG. M.
C.Fleisch, D.Bremerich, W.Schulte-Mattler, A.Tannen,
A. T. Teichmann, W. Bader, K. Balzer, S. P. Renner,
T.Römer, S.Roth, F.Schütz, M.Thill, H.Tinneberg, and
K. ZarrasGeburtshilfe Frauenheilkd. 2015 Aug; 75(8):
792–807. doi: 10.1055/s-0035-1557776). Permission not
requested
Fig. 4.13 Stirrups with foot and ankle support to avoid
pressure on the calf. From the web. Permission not
requested
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G. Giambartolomei et al.
Extra caution should be taken when moving
the patient from supine to prone, especially to
endotracheal tube, vascular access, and shearing
of the skin that could result in injuries.
The head should be placed on a supporting
device and gently turned laterally to provide
airway access. In females with large breasts,
these should be positioned laterally; in males,
genitalia should be appropriately placed to avoid
compression or torsion.
Ankles and feet should be placed in the neutral position with the aid of a padded footboard;
hips and knees should be slightly exed.
Important pressure points in the prone position are ears, eyes, cheeks, acromion processes,
Saphenous nerve
Peroneal nerve
Fig. 4.14 Nerves potentially affected by incorrect lithotomy position. From the web. Permission not requested
Femoral nerve
obturator nerve
iliac crests, patellae, and toes, which should be
adequately padded.
Common complications occurring after
prone interventions are facial swelling, chemosis, and temporary blurred vision. Other rare
complications are corneal abrasions, ischemic
optic neuropathy, and central retinal artery
thrombosis which could result in permanent loss
of vision, as already discussed.
4.4 Skin Prep
Since 1867, the year of Lister’s “Antiseptic
principle of the practice of Surgery” publication, great efforts have been employed in
ensuring an increasing rate of sterility of the
surgical eld.
The introduction of sterile gloves and hand
scrubbing certainly reduced the incidence of
healthcare-associated surgical site infections
(SSIs). However, according to WHO, the burden
of this preventable complication is of 20,196 SSIs
out of 2,417,933 surgical procedures performed in
the USA in 2014, accounting for about an extra
900 billion US$ [11]. There is no clear-cut level of
bacterial skin load that should be removed before
surgery; however 80% of bacteria in surgical site
infections derive from the skin of the patient. In
order for a product to be approved to use as disinfectants, the Food and Drug Administration
requires a reduction of colony- forming units
(CFU) by more than two log10 at dry sites (e.g.,
Fig. 4.15 Prone position (taken from web)
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