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Файл:Ординатура / Хирургия / Библиотека им академика М.И. Перельмана / Книга_605_Библиотеки_им_академика_М_И_Перельмана.pdf
CHAPTER 4
Preconditions of Successful
(Gastrointestinal) Surgery
The development of modern academic surgery was almost breath-taking
and highly appreciated by the public. Quite a number of books of popular
literature glorified the advances in surgery, e.g., “The century of the surgeon” by J. Thorwald (London 1957). However, it would not have been
conceivable without some significant achievements which modified the
frame conditions. At least three of them have to be addressed in detail:
• antisepsis,
• anesthesia,
• specialized surgical environment.
Each of these issues deserves special mention.
4.1 ASEPSIS
4.1.1 The Detection of Antisepsis
It is elementary school knowledge today that bacteria cause inflammation
and infectious diseases. Each of us knows that disinfectants have to be
applied in case of a skin lesion to prevent infection and impaired wound
healing.
In the past, surgeons were well aware of the fact that some wounds
healed on the spot without any tissue irritation (“primary healing”)
(
Fig. 4.1A), but the majority healed—if at all—after a long tedious pro-
cess of inflammation, pus formation, and granulation formation (“secondary healing”) (
happy few were saved from secondary wound healing. Because of the
high risk of (frequently lethal) inflammation, surgery was avoided whenever possible.
A first breakthrough in a better understanding of primary and secondary wound healing was achieved in the second third of the 19th century.
Independently of each other, Ignaz Semmelweis in Vienna (
and Oliver Wendell Holmes in the United States were concerned about
Fig. 4.1B). However, it was completely unclear why a
Fig. 4.2A)
Biomedical Engineering in Gastrointestinal Surgery. © 2017 Elsevier Inc.
All rights reserved.
61
62
Biomedical Engineering in Gastrointestinal Surgery
Figure 4.1 (A) Primary wound healing: normal aspect of the sutured incision;
(B) secondary wound healing: swelling, reddish color, elevated temperature, and
pain. The edges of the wound did not unite. When the stitches were removed, a
large amount of pus emptied (arrow). All from MITI.
Figure 4.2 (A) Ignaz Semmelweis (181865) copperplate engraving by Jeno Doby
(r Deutsches Medizinhistorisches Museum Ingolstadt, Stephanie Papelitzky);
(B) Semmelweis in Vienna: The detection of contamination. In the famous painting of
Robert Thom, the key message is made clear: hands have to be cleaned and disinfected before the next patient is examined. (B) From the collection of Michigan
Medicine, University of Michigam Gift of Pfizer, UMHS.
the high mortality rate of puerperal fever of women hospitalized for
childbirth.
Close clinical observation made it clear that direct contamination with
the hands transmitted the infection and not—as hypothesized—spread by
air, food, or other transmitters. Regular washing of hands, changing of
clothing, and, in particular, remaining away from other patients after
attending one with clinically manifest infection drastically reduced morbidity and mortality (
Fig. 4.2B). However, the true nature of the vehicle
Preconditions of Successful (Gastrointestinal) Surgery
Figure 4.3 (A) Lister’s carbolic acid sprayer (r Deutsches Medizinhistorisches Museum
Ingolstadt, Michael Kowalski); (B) carbolic acid (phenol) is a poisonous substance.
Highly diluted it was used as a powerful antimicrobial agent. From MITI.
63
remained unknown until two additional advances could be achieved:
Pasteur detected a special type of microorganism—bacteria—and Lister
recognized their implications in secondary wound healing. The challenge
now was to find suitable ways to eliminate or destroy these agents.
Lister propagated carbolic acid sprays and soaking of suture material,
including the consequent washing of hands (
Fig. 4.3).
Lister’s ideas were most effectively promoted in Germany due to the
pioneer activities of Ernst von Bergmann. The success was striking, but
the distribution of carbolic acid sprays was not very practical and harmful
for the OR team. The better idea was to deliver all items after primary
sterilization to the OR table. A few years later, a reliable and nondestructive method was identified. The technique of steam sterilization was
developed in 1886 and strict aseptic rituals were established (
Fig. 4.4).
In the following decades, antisepsis w as continuously refined. The patients
werecoveredwithsterilesheetswhichleftopenonlythesurgicalsite.
Next, surgeons learned to protect the patient from contamination by
the OR team. Face masks and OR caps were introduced. The body was
covered by sterile coats. The famous American surgeon Dr. William
Halsted stimulated Goodyear Rubber company in 1889 to produce thin
rubber gloves
[1]. Though originally intended to protect the hands against
toxic disinfective agents, the importance of gloves to prevent infections of
the surgical incision was soon realized.
In the beginning, almost everything had to be reusable, since repro-
cessing (washing, sterilization) was by far cheaper than the procurement
64
Biomedical Engineering in Gastrointestinal Surgery
Figure 4.4 (A) Historical instrument container for sterilization (r Deutsches
Medizinhistorisches Museum Ingolstadt, Michael Kowalski); (B) a sterile container with
surgical pliers to handle the instruments. From MITI.
Figure 4.5 (A) Patient completely covered by surgical drapes; (B) surgeon with
clothes, OR cap, surgical mask, and gloves. All from MITI.
of sterile disposables. Today, the overwhelming majority of clothes, drape,
masks, gloves, sponges, etc. are provided as sterile disposable items, being
a huge market of its own right in the health care business (
Fig. 4.5).
Another important aspect of surgical asepsis is to reduce the germ
load of the patient’s skin (and of the surgeon’s hands, since gloves alone
are not 100% safe to avoid contamination).
A large variety of highly effective and skin-friendly antiseptics was
developed and these are now commonly available (
Table. 4.1).
Table 4.1 Commonly used surgical skin disinfectants
Group Agent Additional use
65Preconditions of Successful (Gastrointestinal) Surgery
Alcohols Ethyl alcohol 70%; isopropyl
alcohol 70%
Quaternary
ammonium
compounds
Chlorhexidine
and other
diguanides
Quinolone
derivatives
Antibacterial
dyes
Peroxides and
permanganates
Halogenated
phenol
derivatives
Benzalkonium chloride; cetrimide;
methylbenzethonium chloride;
benzethonium chloride;
cetalkonium chloride;
cetylpyridinium chloride;
dofanium chloride; domiphen
bromide
Chlorhexidine gluconate;
chlorhexidine acetate
Hydroxyquinoline sulfate;
potassium hydroxyquinoline
sulfate; chlorquinaldol;
dequalinium chloride;
diiodohydroxyquinoline
Proflavine hemisulfate;
triphenylmethane; brilliant green;
crystal violet; gentian violet
Hydrogen peroxide solution;
potassium permanganate solution;
benzoyl peroxide
Chlorocresol; chloroxylenol;
chlorophene; hexachlorophane/
hexachlorophene; triclosan
Preservative
Irrigations; eye
drops;
preservative;
soaps
Suitable for
mucosa
Treat wounds;
throat lozenges
Treatment of skin
lesions
Wound cleanser;
irrigations
Medicated soaps
and solutions
Application has to be performed according to the recommendations
of the provider. At any rate, the skin has to be cleansed before disinfection. Very hairy regions of the body are mostly shaved immediately prior
to disinfection.
Additional measures are established to prevent contamination of the
patient. After each individual surgery, the OR has to be cleansed thoroughly
according to well defined standards. All surfaces have to be easy-to-clean.
Any devices or equipment not in use have to be removed.
In the past, even so-called laminar air flow systems were established.
Specially treated air (filtering, temperature control, etc.) enters the
surgical site unilat erally (mostly from the air distributor mounted to
the ceiling) in a laminar flow with minimal turbulence to minimize
66
Biomedical Engineering in Gastrointestinal Surgery
the risk o f infection. However, its effectiveness is still unclear [2]
(see Section 4.3: Dedicated Workplace: The Operating Room).
At any rate, antisepsis remains a key pillar of moder n surgery
[3],even
more so with the rising importance of hospital-acquired infections and
multidrug resistance in bacteria (e.g., methicillin-resistant Staphylococcus
aureus which is not only resistant to methicillin but also resistant to most
other types of antibiotics).
4.1.2 Reprocessing of Surgical Instruments
Surgical instruments are high quality products with a more or less
complex function which cannot be thrown away after a single use.
Reprocessing is required after their use in a surgery, which includes
thorough cleaning, check of function, and sterilization.
Immediately after use, the instruments should be rinsed under warm
water to remove all blood, body fluids, and tissue. The next step is
cleaning, either manually or by an automatic washer or ultrasonic device.
The aim is to remove completely all organic deposits since even minimal
staining makes sterilization ineffective.
Manual cleaning is time-consuming and tedious, but often inevitable in
case of micro- and delicate instruments (
of instruments can be treated in an ultrasonic cleaner (
The ultrasonic cleaner removes debris by cavitation. The effect is
enhanced by a special cleaning solution with detergents and enzymes. It is
a comparatively fast (1015 minutes) process and the instruments are
treated rather gently. However, they should not touch each other and a
mixture of instruments of different metallic material should be avoided.
Fig. 4.6A). However, the majority
Fig. 4.6B).
Figure 4.6 (A) Manual instrument cleaning; (B) ultrasound cleaning. All from MITI.
Preconditions of Successful (Gastrointestinal) Surgery
Figure 4.7 Modern instrument processing unit: (A) instrument washing machine in the
OR; (B) washing machines in a central reprocessing and sterilization unit. All from MITI.
67
After washing, the instruments have to be rinsed again with deionized
or distilled water and dried, which is done fully automatically by modern
washing machines (
Fig. 4.7).
The first step of reprocessing is finished by inspecting each instrument
for proper function and condition. It has to be made sure that all of them
are visibly clean and free from stains and tissue.
Scissor blades must glide smoothly all the way (they must not be loose
when in the open position). Forceps should have properly aligned tips.
Hemostats and needle holders should not show light between the jaws
and should lock and unlock easily. The jaw faces of needle holders have
to be checked for wear. Cutting instruments and knives should have
sharp, undamaged blades.
4.1.3 Sterilization
After the sterilization pr ocedur e, no living organism should have survived on
the instrument. All instruments which have a “metal-to-metal” action such as
scissors, hemostats, and needle holders have to be lubricated with dedicated
surgical lubricants before they are put into the sterilization container .
Before the sterilization begins, instrument sets have to be stored in
containers which are locked and not opened again until they finally come
into use at the OR table (
The most important method is steam sterilization: autoclaving.
Sterilization is achieved by the high temperature that steam under pressure
can reach (134˚C). Other possibilities are Ethylene oxide sterilization
Fig. 4.8).
68 Biomedical Engineering in Gastrointestinal Surgery
Figure 4.8 (A) Repacking of the instrument containers according to pack lists;
(B) to avoid any mistakes during this procedure, images of the standard instrument
content are provided. All from MITI.
Table 4.2 Sterilization methods
Method Duration Comment
Steam: Including prions
(autoclaving) 134˚C 30 PSI 60 min
Gas/plasma: Materials which are moisture-
and heat-sensitiveETO; 1618 h
Formaldehyde; 1618 h
Hydrogen peroxide plasma; 1 h
Ozone 4.5 h
Chemical: Endoscopes
Peracetic acid;
Glutaraldehyde; 50 min
Formaldehyde
Ionizing radiation: Only for industrial use
Beta particles;
Gamma rays
Microwave 30 s Surfaces only
Dry heat 170˚C/30 min Anhydrous oils;
Variable
160˚C/60 min Petroleum,
150˚C/150 min bulk Powders
(ETO gas), chemical sterilization, and radiation sterilization. Gas plasma is
especially appropriate for very delicate instruments and materials (
Tab le 4 . 2).
Modern reprocessing and sterilization units in hospitals provide most
of the methods as mentioned above with the exception of radiation
which is almost exclusively used for industrial purposes.
Preconditions of Successful (Gastrointestinal) Surgery
Figure 4.9 (A) Delivering the containers into the sterilization machine; (B) surveillance of the sterilization procedure by computerized control. All from MITI.
69
Figure 4.10 Central store of sterilized items ready for delivery to the OR units. From
MITI.
The reprocessing and sterilization process today is a highly industrialized segment within the overall a ctivities of a surgical hospital
(
Fig. 4.9). It goes without saying that it is prone to str ict quality control.
For example, regular biological tests are mandatory, such as spore
testing. Spores belong to the most resistant biological systems. It has to
be proven that they are completely destroyed during the sterilization
process.
An adequate amount of sterilized instrument sets has always to be
available at the central store (
Fig. 4.10).
70 Biomedical Engineering in Gastrointestinal Surgery
The aspect of further resterilization has always to be considered if a
new instrument or device is created. Effective processing of used instr uments always requires the complete removal of any organic material,
which becomes increasingly difficult the more complex the mechanical
construction is. Despite modern sophisticated cleansing methods (e.g.,
ultrasound), it soon becomes impossible to clean reliably tiny gears, working channels, and Bowden wires.
An instructive example is the instruments of modern master-slave systems. These very complex devices are too expensive to be thrown away.
They have to be resterilizable. However, reprocessing is not reliable
enough to guarantee 100% effectiveness. As a compromise, their use is
stopped automatically after the ninth or tenth case of application by an
in-built deactivation mechanism.
The alternative is to use disposable instruments which are becoming
increasingly more popular.
4.2 ANESTHESIA
Pain is an uncomfortable sense but of high biological importance since
it indicates any damage in the body. It activates mechanisms of
avoidance and protection and insofar it also promoted the development
of medicine since one of the mos t impor tant aspects of medical care is
to eliminate pain.
For many thousands of years, only a few and low-effective agents
were available to fight pain: morphine derivates, alcohol, nicotine enemas, etc. did not help much but were accompanied by severe side effects
and were very difficult to control.
Evidently major, long-lasting surgical operations were inconceivable,
since human beings were simply unable to tolerate the stress and pain
induced by, e.g., an abdominal operation.
Amputation of the extremities was the utmost limit.
It can only be acknowledged retrospectively, how revolutionary an
event it was that took place in Boston in 1846 (
On October 16, 1846, a Boston dentist by the name of William T.G.
Morton demonstrated the use of ether during surgery. Using an ethersoaked sponge, Morton anesthetized a Boston printer named Gilbert
Abbott. Once Mr. Abbott was unconscious, surgeon John Collins Warren
removed a tumor from under his jaw. When the patient came to and
reported he had felt no pain, Dr. Warren turned to the audience in
Fig. 4.11).