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J. I. Ikechebelu and C. O. Ezeama
cycle in the generator. It combines the cutting
and coagulation modes at different percentages.
Hence, we have blend 1 (duty cycle 50%),
blend 2 (duty cycle 40%), and blend 3 (duty
cycle 25%).
5 The System
The electrosurgical generator is basically a ‘bipolar system’ in that it contains two electrodes. The
difference in instrument nomenclature is derived
from the function of the second electrode. In
bipolar instruments, only the portion of tissue
between the electrodes has current passing
through it to complete the circuit. In monopolar
instruments, the patient completes the circuit
between the active electrode and the passive second electrode which acts as the dispersive electrode [5] (see Fig.2).
5.1 Monopolar Circuits
High-density current enters tissue from small
active electrodes creating secondary thermal
events. Current ows through the patient via a
myriad of conductive pathways. Current is dispersed over a large surface return electrode.
Current returns to isolated ground housed in the
electrosurgical generator (grounding is rarely
seen in contemporary ESUs); see Fig.3.
This second electrode is needed to disperse
the current which has passed through the patient.
Since the passive (dispersive) electrode has a
relatively large surface area, the current density
at its site is very low which minimizes the potential for patient injury at its location. The active
electrode is typically small and pointed to allow a
high current density at its tip. This facilitates the
tissue effect needed at the point of surgery, e.g.
cutting, coagulation, fulguration, etc.
Fig. 2 The electrosurgical systems: monopolar and bipolar circuits
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Fig. 3 The electrosurgical systems: isolated vs. ground-reference circuit
In hysteroscopic surgery where uid distension media are used, monopolar effects are modulated by the type of uid medium.
Electrolyte-containing distension media are
effective conductors and they act to enlarge the
surface area of the active electrode. This dramatically reduces the current density which attenuates the electrosurgical effect. Non-conductive
distension media are effective insulators. Typical
examples are glycine, sorbitol and mannitol. In
such media, the current density is maintained, the
electrosurgical effect is unaltered; therefore, desiccation, cutting, vaporization and fulguration are
all available.
The passive electrode (return plate) is equally
important during surgery with monopolar instruments. The large surface area of its dispersion
pad results in low current density at the attach-
ment site, thus minimizing the risk of skin burns.
The dispersive pad is attached as close as possible to the surgical eld. The pad should be applied
over a large muscle and away from metallic body
implants; this prevents the occurrence of burns.
The modern electrosurgical generators have sensors that measure pad-to-skin contact and current
density and block its function in case of any contact failure.
Monopolar surgery is very attractive because
it is relatively more available; it is also cheaper to
procure. It has many diverse tissue applications
like cutting and fulguration as has been described
above.
Its drawbacks are related to the potential for
injuries remote from the operation site and also
its inability to seal vessels larger than 2mm in
diameter [10].
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5.2 Bipolar Circuits
Unlike the monopolar units, the simplest bipolar
system is designed with both electrodes (passive
and active) positioned on the same instrument
[11, 12]. Thus, instead of current passing through
the whole patient to the dispersive electrode, only
the tissue within the connes of the electrodes on
the instrument is affected by the current. See
Fig.2. Since the return electrode is included in
the circuit at the site of surgery, the dispersive
patient return electrode pad is unnecessary, and
the rest of the patient’s body does not form part of
the electrosurgical circuit. Current is symmetrically distributed through the tissue between the
two electrodes. Thermal damage is limited to a
discrete volume of tissue, and power requirements are reduced leading to higher electrosurgical efciency. The depth of thermal spread is less
than 1mm unlike in monopolar surgery where it
is 3–5mm.
Due to the relative constancy of energy delivered, it is more difcult to execute electrosurgical
vaporization and almost impossible to cut efciently. Coagulation is the major mode employed
but it takes a longer period of instrument application to coagulate due to the lower power settings,
which leads to charring and tissue adherence with
incidental tearing of adjacent blood vessels [13].
5.3 Advanced Bipolar Systems
(Aka Tripolar Systems)
This is the introduction of cutting components in
bipolar units to overcome the challenge of cutting
which is lacking in bipolar instruments. An
example is the Versapoint system which can
coagulate and cut with its dedicated electrosurgical generator. These devices come with a retractable blade and offer very good haemostasis with
a less lateral spread of heat. Vessels of up to 7mm
in diameter can be sealed.
There are also the ultrasonic systems like harmonic which can give a bipolar cut and coagulation using mechanical vibrations. These tripolar
devices can perform four functions in one—grasping, dissecting, coagulation and cutting. See Fig.4.
J. I. Ikechebelu and C. O. Ezeama
Fig. 4 Harmonic generator and hand piece
6 Complications ofElectrosurgery
6.1 Direct Application
Injury by direct application of the electrosurgical probe can arise either from mistaken target
or unintended activation. The speed of the procedure will result in either less or more coagulation and thermal spread. The proximity between
the electrode and the tissue can determine contact (desiccation) or non-contact tissue effect
(fulguration).
6.2 Stray Current
A stray current arising from defective insulation
can injure the bowel or blood vessels. A careful
preoperative inspection of equipment and after
use is the best means of identifying defective
insulation. The two major causes of insulation
failure include the use of high-voltage currents
and the frequent re-sterilization of instruments,
which can weaken and break the insulation. The
risk of an insulation break increases when using a
5-mm insulated instrument through a 10-mm
sleeve, or by repeated use of the disposable
instrument.
6.3 Direct Coupling
Direct coupling occurs when the active electrode
is accidentally activated when it is in contact
with or in close proximity to another metal
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instrument within the pelvic cavity, e.g. laparoscope or metal irrigation apparatus. Direct coupling can be prevented with visualization of the
electrode and avoiding contact with any other
conductive instrument prior to activation of the
electrode.
6.4 Capacitive Coupling
Capacitive coupling occurs when the electric current is transferred from one conductor (the active
electrode), through intact insulation, into adjacent conductive materials (e.g. metal cannula)
without direct contact. A longer length of instruments, thinner insulation, higher voltages and
narrow trocars increase the risk of this type of
injury. Capacitor coupling can be minimized by
activating the active electrode only when it is in
contact with target tissues and limiting the time
length of high-voltage peaks.
6.5 Return Electrode or
Alternative Site Burns
The grounding (dispersive) pad used in the
monopolar circuit offers the path of least resistance from the patient back to the generator and
ensures an area of low current density. If the
return electrode is not completely in contact with
the patient’s skin or is not able to disperse the
current safely, then the exiting current can have a
high enough density to produce an unintended
burn. It is important to have good contact
between the patient and a dispersive pad (application of a gel on the pad before application will
improve on the contact with the skin). A burn at
an alternative site can occur if the dispersive
(ground) pad is not well attached to the patient’s
skin. When the dispersive pad is compromised in
the quantity or quality of the pad or patient interface, the electrical circuit can be completed by
some small, grounded contact points such as
electrocardiogram leads, towel clip, intravenous
stand, etc. and produce high current densities,
causing a burn.
6.6 Infection Spread
There is the potential for transmission of disease
from patient to physician or ancillary personnel.
The discharge of an electrosurgical current over a
droplet of uid causes spattering over a distance
of at least 5cm [14]. This is because electrosurgery causes an expansion of tissue uids resulting in the explosion of cells, and an aerosol of
blood and uid droplets is created that can potentially transmit infectious agents. It is important,
regardless of the surgical procedure being performed, that all personnel observe universal
precautions.
6.7 Carcinogenic Smoke
Smoke generated by electrosurgical procedures
is mutagenic, 16 giving additional impetus to the
recommendation that surgical masks be worn.
Also, smoke siphoning instruments have been
developed to minimize this risk. The surgical
smoke can also provoke allergic reactions or
responses like in asthmatic health workers
involved in the operating room.
7 Advances inElectrosurgery
7.1 Advanced Bipolar Vessel
Sealers
This improvement utilizes bipolar coagulation
using a high current and low voltage with pressure on the tissue. The subsequent denaturation
of the tissue results in a coagulum which is an
excellent vascular seal. A system that calculates
the energy needed to achieve this seal is built into
the generator which reduces collateral damage by
thermal spread [11].
7.2 Ultrasonic Devices
This device is not strictly an electrosurgical
device. Instead of electricity generated in the tissue, it uses ultrasound technology to achieve its
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J. I. Ikechebelu and C. O. Ezeama
tissue effect. Mechanical vibrations (55.5 kHz)
above the audible range generate heat, which in
conjunction with compression and duration of
use causes the vascular seal to occur. Cutting
blades allow excision using the same instrument.
There is less collateral damage than with either
monopolar or bipolar usage, less smoke and less
char formation. Currently, vessels of up to 5mm
can be sealed by these devices [14–16].
7.3 (Hybrid Technology)
Thunderbeat Technology
It is a combination of advanced bipolar energy
and harmonic energy. This new technology allows
integrated cutting and sealing with much more
efciency. It enables a surgeon to simultaneously
seal and cut vessels up to and including 7mm in
size with minimal thermal spread [17–19].
8 Conclusion
Advances in electrosurgical techniques have certainly had a signicant impact on the practice of
endoscopic surgery. To achieve desired outcomes
and protect patient safety, the operator must be
aware of the technology and its appropriate use.
Learning Points
• The electrosurgical unit generates alternating
high-frequency current to produce desired
thermal effects on tissue.
• Instruments used may be monopolar if the
second electrode is passive or bipolar if the
second electrode is active.
• Monopolar instruments need a dispersive pad
to allow the exit of current from the patient,
while bipolar instruments do not.
• Manipulating the delivery of current at the ESU
(duty cycle) allows different thermal effects,
e.g. cutting, coagulation and fulguration.
• More efcient instruments are being devel-
oped to optimize haemostasis and transection
of tissues at surgery.
References
1. Nayab M. History of Amal-i-Kaiyy (cauterization) and its indications according to the shapes of
instruments: a review. Int J Med Sci Public Health.
2017;3(3):60–1.
2. Alsanad SM, Asim AA, Gazzaf IMA, Quresh
NA.History of cautery: the impact of ancient cultures.
JAMMR. 2018;25(9):1–17.
3. Zimmerman LM, Veith I. Great ideas in the history
of surgery. USA: The William & Wilkins Company;
1961.
4. Jeffery BS, O’Connor L, David MD, Bloom
A. William T Bovie and electrosurgery. Surgery.
1996;119(4):390–6.
5. Jones CM, Pierre KB, Nicoud IB, Stain SC, Melvin WV
3rd. Electrosurgery. Curr Surg. 2006;63(6):458–63.
6. Lacourse JR, Miller WT 3rd, Vogt M, Selikowitz
SM. Effect of high-frequency current on nerve
and muscle tissue. IEEE Trans Biomed Eng.
1985;32:82–6.
7. Taheri A, Mansoori P, Sandoval LF, Feldman
SR, Pearce D, Williford PM. Electrosurgery: part
I. basics and principles. J Am Acad Dermatol.
2014;70(4):591.
8. Massarweh NN, Cosgriff N, Slakey
DP. Electrosurgery: history, principles, and current
and future uses. J Am Coll Surg. 2006;202(3):520–30.
9. Ferreira H, Ferreira C. Principle and use of
Electrosurgery in laparoscopy. In: Agarwal M, Mettler
L, Alkatout I, editors. A manual of minimally invasive Gynaecology. 1st ed. Jaypee Brothers Medical
Publishers [p] ltd.; 2015. p.69–77.
10. Lyons SD, Law KS.Laparoscopic vessel sealing technologies. J Minim Invasive Gynecol. 2013;20:301–7.
11. Phipps JH.Understanding electrosurgery: safety and
efciency. In: Lower A, Sutton C, Grudzinskas G,
editors. Introduction to Gynecological Endoscopy.
Oxford, UK: Iris Medical Media; 1996. p.39–56.
12. Kennedy JS, Stranahan PL, Taylor KD, Chandler
JG. High-burst-strength, feedback-controlled bipolar
vessel sealing. Surg Endosc. 1998;12(6):876–8.
13. Tucker RD, Voyles CR. Laparoscopic electrosurgical complications and their prevention. AORN J.
1995;62:51–3.
14. Colver GB, Peutherer JF. Herpes simplex virus dispersal by Hyfrecator electrodes. Br J Dermatol.
1987;117:627.
15. Fencl JL.Guideline implementation: surgical smoke
safety. AORN J. 2017;105(5):488–97.
16. Broughton D, Welling AL, Monroe EH, Pirozzi K,
Schulte JB, Clymer JW.Tissue effects in vessel sealing and transection from an ultrasonic device with
more intelligent control of energy delivery. Med
Devices (Auckl). 2013;6:151–4.
17. Newcomb WL, Hope WW, Schmelzer TM, et al.
Comparison of blood vessel sealing among new
electrosurgical and ultrasonic devices. Surg
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Endosc. 2009;23(1):90–6. https://doi.org/10.1007/
s00464- 008- 9932- x.
18. Milsom J, Trencheva K, Monette S, etal. Evaluation
of the safety, efcacy, and versatility of a new surgical energy device (THUNDERBEAT) in comparison
with harmonic ACE, Ligasure V, and EnSeal devices
in a porcine model. J Laparoendosc Adv Surg Tech A.
2012;22:378–86.
19. Fagotti A, Vizzielli G, Fanfani F, etal. A randomized
study comparing the use of Thunderbeat technology
vs. standard electrosurgery during laparoscopic radical hysterectomy and pelvic lymphadenectomy for
gynecological cancer. J Minim Invasive Gynecol.
2014;21:447–53.
Anatomy oftheFemale Pelvis
https://t.me/med1917
EugeneM.Ikeanyi, LateefAkinola,
andDennisO.Allagoa
1 Introduction
Knowledge of female pelvic anatomy is crucial
for the diagnosis and surgical management of
female pelvic pathologies including endometriosis and urogenital dysfunctions and in gynaecological oncology staging and treatment of pelvic
tumours [1]. It is undoubtedly crucial for the
understanding of the fundamental mechanisms of
urogenital dysfunction and treatments. Detailed
pelvic anatomy is equally very essential to understand the relationship of the pelvic anatomic
E. M. Ikeanyi (*)
Department of Obstetrics and Gynaecology, Niger
Delta University, Amassoma, Bayelsa State, Nigeria
L. Akinola
Medison Specialist Women’s Hospital, Fertility
Assyst, Lagos, Nigeria
D. O. Allagoa
Department of Obstetrics and Gynaecology, Niger
Delta University, Amassoma, Bayelsa State, Nigeria
Federal Medical Centre,
Yenagoa, Bayelsa State, Nigeria
structures and organs for interpretations and
diagnosis in hysterosalpingogram (HSG), pelvic
scans, computerized tomography (CT), magnetic
resonance imaging (MRI), and dynamic MRI [1].
Furthermore, pelvic surgery requires a comprehensive knowledge of the pelvic anatomy to
safely access, optimize exposure, ensure haemostasis and avoid injuries to other pelvic viscera,
blood vessels and nerves.
It is important to note that the pelvis is anatomically subdivided into anterior, middle and
posterior compartments with the middle compartment only in the female pelvis [1]. The contents of the posterior compartment are the
rectum and anus. The anterior compartment
consists of the bladder and urethra, while the
middle compartment (the focus of this discussion) consists of the ovary, fallopian tubes,
uterus, vagina and associated neurovascular
bundles (Fig.1).
Anatomic features that are clinically applicable to female pelvic surgery are highlighted
throughout the text, together with the symbol *.
© The Editor(s) (if applicable) and The Author(s), under exclusive license to Springer Nature
Switzerland AG 2022
J. E. Okohue et al. (eds.), Gynaecological Endoscopic Surgery,
https://doi.org/10.1007/978-3-030-86768-3_5
47
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E. M. Ikeanyi et al.
Fig. 1 Sagittal view of female pelvic organs
2 Synopsis ofPelvic Anatomy
The pelvic region is the area between the trunk or
main body and the lower extremities, or legs. The
female pelvis is anatomically and morphologically different from that of the male. Most of the
differences are not apparent until puberty. The
female pelvic bones are larger and broader as
they have evolved to create a larger space for
childbirth. The most noticeable differences are
the width of the pubic outlet, the circular hole in
the middle of the pelvic bones and the width of
the pubic arch, or the space under the base of the
pelvis.
The bones of the pelvis are the hip bones,
sacrum and coccyx. Each hip bone contains three
bones, the ilium, ischium and pubis. These bones
fuse as we grow older. The sacrum is made up of
ve fused vertebral bones, joining the pelvis at
the crests of the ilium. Below the sacrum is the
coccyx, or tailbone, a section of fused bone that is
the end of the vertebral column. The pelvis
provides the base of the spine as well as acetabular sockets of the hip joint.
The contents of the female pelvis including
the small and large intestines are supported by a
series of muscles known as the pelvic oor. These
muscles assist in vaginal delivery and help push
the baby through the pelvic outlet and vaginal
opening during childbirth.
*Note: During the embryological period, failure of some developmental processes of the
female genital tract results in some congenital
anomalies of endoscopic surgical importance
mostly from Mullerian ducts, Mullerian tubercle
and urogenital sinus development.
Anatomy oftheFemale Pelvis
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49
Mullerian developmental failures can result in
congenital utero-cervical and vaginal anomalies,
for example, uterus didelphys, bicornuate or unicornuate, or fully septate or partially septate
uterus, with varying degrees of severity. From the
Mullerian tubercle and sino-vaginal bulb complex, various degrees of transverse and/or longitudinal septa can result in failed canalization of
the cervix and vagina.
At birth, the bones that make up the pelvis are
the ilium, ischium, pubis, sacrum and coccyx. The
ilium, ischium and pubis fuse by age 16–18years
to form a single bone, referred to as the pelvic
bone. Thus, in an adult, the bones of the pelvis
consist of the right and left pelvic bones (hip
bones), the sacrum and the coccyx. The bony pelvis is the rigid foundation to which all of the pelvic ligaments and muscles are anchored.
Each hip bone contains three bones—the
ilium, ischium and pubis—which fuse as we grow
older. The sacrum, consisting of ve fused vertebral bones, joins the pelvis at the crests of the
ilium. Below the sacrum is the coccyx, or tailbone,
a section of fused bone that is the end of the vertebral column. The pelvis forms the base of the
spine as well as the socket of the hip joint (Fig.2).
The most superior component of the pelvic
bone is the ilium. The upper part of the ilium
expands to form a at fan-shaped ‘wing’, which
provides support for the lower abdomen and is
also called the false pelvis. The medial surface of
the ilium has two concavities forming the lateral
borders of the pelvic outlet (the inferior opening
of the pelvis). The superior and larger of these
two concavities is the greater sciatic notch
(boundaries are the sacrum, ilium and ischial
spine) (Fig.2).
The surgical landmarks of the bony pelvis are
the ischial spine, pubic arch, pectineal line, obturator foramen and coccyx.
The female upper genital tract consists of the
cervix, uterine corpus, fallopian tubes and ovaries. A sagittal view of the female pelvis is shown
in Fig.1. The lower genital tract consists of the
vulva and vagina.
Key Areas of Note
1. Uterus: uterine corpus, uterine cervix, uterine
support structures (uterosacral and cardinal
ligament complex, round ligaments, broad
ligaments and the endopelvic fascia).
2. Adnexa: ovaries, fallopian tubes (Fig.3).
3. Vasculature (common and external iliac
vessels, inferior and supercial epigastric
vessels, anterior division of the internal
iliac artery forming the main blood supply
to the uterus).
Sacral promontory
Ala sacrum
Anterior Superior
Iliac spine
Ischial spine
Fig. 2 Bones of the female pelvis
Lumbar ver
Sacro-iliac joint
Iliac bone
SACRUM
Femoral head
in aetabular
fossa
COCCYX
Pubic ramus
Pubic symphysis
tebrae
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Fig. 3 The genital tract
and other pelvic viscera
E. M. Ikeanyi et al.
4. Lymphatics (obturator lymph nodes, internal
iliac lymph nodes, external iliac lymph nodes,
supercial inguinal lymph nodes, para-aortic
lymph nodes, lymphatic drainage of the pelvic viscera, uterus and proximal vagina, ovary,
distal vagina and vulva).
5. Nerves (aortic plexus, superior and inferior
hypogastric plexuses, lumbosacral plexus and
the nerves of the anterior abdominal wall).
6. Lower urinary tract: ureter, urinary bladder
(Fig.3) and urethra.
7. Sigmoid colon (Fig.3), rectum and anus.
3 The Lower Anterolateral
Abdominal Wall
The anterolateral abdominal wall layers comprise
the skin, subcutaneous fat and anterior layer of fascia; medially, the rectus abdominis muscles; and
laterally, the three layers of the external oblique,
internal oblique and transversus abdominis muscles. Underneath the skin is the left and right rectus abdominis muscles in the midline, and laterally
to the rectus abdominis are the oblique abdominis
muscles—external and internal obliques—and the
innermost transversus abdominis which is underlayered by the abdominal peritoneum.
The rectus abdominis is separated by the linea
alba, a midline tendinous raphe. These muscles
connect the pubic bone (pubic crest and symphysis) to the xiphoid process and the medial ends of
the fth and seventh costal cartilages. The rectus
abdominis has tendinous intersections at the level
of the umbilicus and between the umbilicus and
the pubic bone below and the umbilicus and the
xiphisternum above. It tilts the pelvic bone and
ventrally exes the trunk.
The external oblique muscle is attached
between the external surfaces of the fth to the
12th rib to the midline linea alba, iliac crest and
pubic tubercle, while the internal oblique lying
underneath it has its attachment from the thoracolumbar fascia, the lateral two-thirds of the iliac
crest and inguinal ligament to the linea alba, borders of the tenth to 12th ribs and through the conjoint tendon to the pubic bone. The transversus
abdominis is attached to the seventh to the 12th
rib cartilages, the iliopsoas fascia and the middle
linea alba, pubic crest and pectineal line as part of
the conjoint tendon. These muscles rotate and
ex the trunk and provide support for the abdominal viscera. They are innervated by the thoracicabdominal nerves T7–T11, subcostal nerves and
L1 lumbar nerve.
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