Introduction
Anesthesiology is one of the few major medical specialties where discoveries are
clearly documented, by the introduction of general anesthesia, and local anesthesia
(1,2). The last century has witnessed many developments in the practice of regional
anesthesia. What began as a simple method of numbing body parts of the body during
surgery has expanded to creating a neural blockade during the perioperative period,
either as the sole anesthetic or in combination with general anesthesia. Local anesthetic
agents are also increasingly being used in the treatment of chronic pain syndromes.
Techniques have evolved from topical application and local infiltration to selective
blockade of nerves and plexuses, neuraxial blocks, and the use of ultrasonography
to identify neural structures. The purpose of this review is to offer a comprehensive
curriculum in HORA (history of regional anesthesia) that could be implemented in
training programs.
During a brief online survey conducted regarding the teaching of regional anesthesia
in acute pain programs across the country we realized that much needed to be done in
that matter.
Some of the barriers identified were lack of trained faculty in the topic, time
constrains and most of all the absence of a curriculum to teach HORA. Even the latest
guidelines for fellowship training in regional anesthesiology and acute pain medicine
published by ASRA in 2015 did not include a curriculum to teach HORA.
Discussion and Proposed HORA Curriculum
This review of the history of regional anesthesia puts forward the following topics
as recommendations to be included in the core curriculum for the teaching of HORA: the
emergence of ASRA; local anesthetic agents; spinal and epidural anesthesia; brachial
plexus block; ultrasonography and the recognition that regional anesthesia reduces
morbidity and shorter recovery room stays when compared with general anesthesia in
ambulatory surgery.
The origin of American Society of Regional Anesthesia and Pain Medicine (ASRA)
The original ASRA was founded in 1923. It was created to
honor Gaston Labat, who has been called the "father" of regional
anesthesia and pain medicine in the United States. Labat was a
French surgeon and came to America with Mayo Clinic founder
Charles Mayo. Labat worked in several hospitals in the U.S.
and created a course in regional anesthesia through New York
University at Bellevue Hospital. The original ASRA grew out
of this work with a focus on the development of local,
regional, and spinal anesthesia.
In 1930, Philip Woodbridge presented at an ASRA meeting on
the use of therapeutic blocks for chronic pain, which signified a
shift in focus to also include pain management in the Society's
purview. The association was no longer focused solely on surgical
anesthesia, with pain management becoming increasingly
emphasized in papers and meetings [3].
Despite numerous advances in regional anesthesia and pain
medicine throughout the 1930s, ASRA as an organization began
to lose steam by the end of the decade. Meetings were held less
frequently, and fewer members were paying their dues. In 1940,
the group was dissolved, and members were invited to join the
American Society of Anesthesiology, which had been established
early in the 20th century.
In 1973 Alon Winnie had a vision of an organization that
would be devoted to teaching regional anesthesia. He shared his
vision with Harold Carron, Jordan Katz, Donald Bridenbaugh,
and P. Prithvi Raj, who reestablished the society in 1975 [4].
Interestingly, the reinvented ASRA originally focused on regional
anesthesia but later added pain medicine in the 1990s.
At the time of the society's first meeting on March 18, 1978,
the society had more than 300 members. Today it has more
than 6500 physician and scientist members and the journal
Regional Anesthesia and Pain Medicine, is read by over 9000
subscribers internationally.
Today, ASRA is one of the largest subspecialty medical
societies in anesthesiology. Change is constant in the field of
regional anesthesia and pain medicine as new discoveries are
made, changes occur in healthcare administration and insurance,
and demographic shifts occur in the patient population. Although
many organizations and companies provide offerings to address
the needs of individuals working with these challenges, ASRA
remains committed to a focus on the highest quality of evidencebased
education and research for physicians. This history of
ASRA is relevant to today's anesthesiologist so we don't forget
the heritage of the past to make certain that regional anesthesia
is always available to the patients for whom we care.
Local Anesthetics:
Cocaine: Extracts from the coca plant have been consumed by
natives of the Andes region in South America for over 5000 years
[3,4]. The active ingredient was separated from the leaves
using lime, and used as a stimulant , to decrease air hunger, and
to increase endurance. The Incas were the first to observe local
anesthetic properties of saliva rich with coca extract.
Centuries later, modern chemical processes allowed the
extraction, purification, and identification of cocaine. Richard
Willstatter [1872-1942] elucidated the structure of plant
alkaloids such as atropine and cocaine as part of his doctoral
thesis, and later also explored the structure of chlorophyll.
For his many contributions to the understanding of plant
chemistry,he was awarded the Nobel Prize in Chemistry in
1915 [5,6]. Cocaine's most notable advocate at that time was
Sigmund Freud [1856-1939], the famous psychoanalyst, who
believed it could be used to cure depression, as well as addiction
to morphine or alcohol. He self-experimented with cocaine and
described many of its properties but failed to notice its local
anesthetic properties [7,8]. That distinction went to Freud's
colleague, a rising ophthalmologist Carl Koller [1857- 1944], who
observed the tongue-numbing properties of the drug and his
team continued with self-experimentation feeling no pain as they
touched their own eyes with needles. In 1884 his work debuted
at the German Ophthalmological Society Conference in
Heidelberg and the international medical community quickly
learned about the local anesthetic properties of cocaine [9].
As with the discovery of general anesthesia, controversy arose
about the individual[s] who deserved credit for the discovery
of the local anesthetic properties of cocaine. Two other
'practitioners', Vassily von Anrep [1852-1927] and Theodor
Aschenbrandt claimed to have discovered these properties
before Koller's 1884 presentation, but pressure from the
medical community in Vienna caused them to reliquish their
claims and acknowledge Koller's contribution [10,11]. Later,
other physicians used cocaine to obtain analgesia during
surgery. William Halsted [1852-1922] used cocaine for a
mandibular nerve block during dental surgery [12] and also for
a brachial plexus block [13], while August Bier [1861-1949]
used it intrathecally as an anesthetic [14]. Self-experimentation
resulted in many physicians, including Freud and Halsted,
becoming dependent on drugs such as morphine and cocaine.
Procaine, synthesized in 1905, replaced cocaine due to its
efficacy and longer lasting properties when combined with
adrenaline [15]. Even more important, procaine did not
possess the addictive property of cocaine. Rarely used these days
as a local anesthetic, mostly secluded to ENT [ear, nose, and
throat] procedures, the story of the cocaine illustrates how a
gateway drug laid the foundation for local anesthetic
techniques and a search for improved agents.
Lidocaine: In 1929 two chemists; Hans von Euler [1873-
1964] and Sir Arthur Harden [1865-1940] were awarded the
Nobel Prize for their work on fermentation. Von Euler then
focused his efforts on developing barley strains that were
resistant to loss of agricultural output to insects. He isolated
a new pesticide called gramin. Von Euler and Holger Erdtman
attempted to synthesize gramin but ended up synthesizing the
incorrect isomer isogramin. When placed on the tongue, isogramin
resulted in a temporarily loss of sensation.
In von Euler's laboratory in 1935, Holger Erdtman [1902 1-989]
and Nils LÓ§fgren [1913-1967] synthesized , different anilides with
tongue numbing properties and published their results in
1937[16]. Although none of the agents appeared to be superior to
procaine, LÓ§fgren continued to work on thesceo mpounds until
1942 when his student Bengt Lundqvist [1922- 1953] convinced
him that these drugs ought to be tested by injection rather than
producing numbness of the tongue. After conducting a series of
clinical experiments, they found that compound LL30 showed
great promise as a local anesthetic [17].
Compound LL30 was tested on mice at the Karolinska
Institute [Stockholm, Sweden]and found to have greater efficacy,
longer duration of action and a less toxic profile than procaine.
On July 15, 1943 LÓ§fgren and Lundqvist applied for and
obtained a patent to protect their intellectual property rights. They licensed
the product for a two-week trial and were disappointed when the
medical and pharmaceutical community showed little interest
in their drug. After considering several offers, they
transferred ownership of the patent to Astra Pharmaceuticals
[Sweden] on November 22, 1943 for 15,000 Swedish Crowns
and 4% of all sales for 17 years. Rebranded and tested, Astra
marketed the drug in early 1948 as Xylocaine.
LÓ§fgren finished his doctorate in 1948 and published his
thesis, "Studies on local anesthetics: Xylocaine: a new synthetic
drug" [18]. He stayed on as a professor of organic chemistry at
the University of Stockholm where he was precluded from
winning research grants as a result of his financial success with
compound LL30. Lundqvist sustained a skull fracture after a fall
down a flight of stairs. He died from cerebral hemorrhage at the
age of 30.
Chloroprocaine: When chloroprocaine was introduced to
the market in 1952, lidocaine had already been used for epidural
anesthesia as the first amino-amide anesthetic. Lidocaine was
less likely to produce allergic reactions than the amino esteranesthetics
[19]. In comparison to chloroprocaine, lidocaine
provided a longer duration of action and was cleared less quickly
from the body. Chemically similar to procaine, 2-Chloroprocaine
became popular because of its rapid onset of action and
metabolism by plasma esterases. It had virtually no effect on
maternal-fetal physiology and was used extensively for pain relief
during labor and delivery [20].
Numerous reports in the 1980s describing long term and
even permanent neurological deficits due to local anesthetic
agents sent a shockwave through the practice of regional
analgesia [21]. Half a dozen cases reported prolonged
transient neurological sequelae [TNS] and suggested that the
cause might be accidental intrathecal infiltration during epidural
catheter placement [22]. Reports of more cases involving
accidental intrathecal injection with resulting
permanent neurological sequelae, in some cases causing
sexual dysfunction [23], forced the manufacturer to find ways to
deal with these issues by altering the composition of the
preservatives used in the manufacturing process. In 1987,
Astra removed preservatives and marketed a UV light
protected vial. Nonetheless, fear of causing potentially
permanent neurologic complications lead the Food and Drug
Administration [FDA] to prohibit the use of preservative
containing chloroprocaine for lumbar and caudal epidural
blocks.
Several hypotheses were put forward to explain these
adverse effects. The high dose and volume of the local anesthetic
were blamed initially. However, hundreds of deliberate spinal
injections with the same doses had not produced adverse
results [24]. Several of the early reports involved medications
without preservatives, nonetheless, other studies suggested that
preservatives such as methylparaben, ethylene diamine
tetra acetate [EDTA], and sodium bisulfite were to blame [25].
It was known that these additives significantly prolonged the
shelf life of the drug and inhibited bacterial growth. Studies
on animal models and in-vitro neuronal stem cells showed
proliferative and architectural changes when exposed to 2-
chloroprocaine with and without sodium bisulfite [26].
A study in animals by Taniguchi showed that intrathecal
injection of sodium bisulfite caused less neurological
dysfunction compared to chloroprocaine alone, bringing into
play more confusion about the identity of thecausative agent;
was it the local anesthetic or the preservative? [27]. Despite
this study, FDA regulations restrict Astra, the current
manufacturer of chloroprocaine [Nesacaine-MPF] to market
the drug without bisulfite. In Europe, epidural administration of
chloroprocaine with preservatives is permitted and
surveillance studies have not revealed evidence of neurological
deficit. Thirty years later, there is a lack of clear evidence
pointing to any single mechanism responsible for neurotoxicity
associated with the use of epidural chloroprocaine.
Bupivacaine and its toxicity: Numerous new amino amide
local anesthetics were synthesized between 1898 and 1972
including nirvaquine, procaine, chloroprocaine, cinchocaine,
lidocaine, mepivacaine, prilocaine, efocaine, articaine, etidocaine,
and bupivacaine [28]. Attempts were made to decrease toxicity,
control onset and duration of action, and decrease the likelihood
of drug dependence.
It had already been established that the central nervous
system was more susceptible to local anesthetics when compared
to the cardiovascular system [29]. One pivotal case by Prentiss
illustrated the danger of etidocaine during caudal anesthesia;
causing convulsions and cardiac arrest in a health young male
[30]. More examples of the toxic effects of local anesthetics
emerged as Albright added five other case reports linked to
lipid-soluble anesthetics and the dangerous effects on the
cardiovascular system and the central nervous system [31]. As
is the case with most established practices, resistance erupted
against such causative claims.
Bupivacaine, synthesized in 1957, is of special interest
because of its long duration of action and history of
clinical application. Several case reports highlighted the
potential toxicity of 0.75% bupivacaine. This resulted in much
investigative work to understand mechanisms of its toxicity.
In theory, the toxicity was thought to be related to the cardiac
sodium channels [32]. The anesthetic was further
characterized as "fast-in, slow-out" due to its prolonged
blockade and a potent depressant of the maximum
upstroke velocity of cardiac muscle action potential.
Awareness of this unique behavior of bupivacaine led to the
design of enantiomers, such as levo-bupivacaine and
ropivacaine, each having their own physiological properties.
These drugs, even in their present state, were still incredibly
valuable to multimodal pain techniques and their use was
"rescued" by an astute observation on a patient with carnitinedeficiency.
It was Weinberg who showed that the accumulation
of fatty acids within the mitochondria enhanced the toxicity of
bupivacaine [33]. Therefore, infusion of a lipid would emulsify the
anesthetic and reduce its activity when toxicity was encountered.
This was proven by his series of experiments on dogs and rats
which showed the rescue effect of lipid emulsion therapy on the
cardiotoxic effects of bupivacaine.
Several years later, Rosenblatt showed its utility
during cardiac arrest where electrical defibrillation was
successful only after lipid infusion [34]. The mechanism is
believed to be lipophyllic binding which isolates the drug in a
"lipid sink".
Understanding the history behind the creation of these
drugs allow a better appreciation in our daily practice.
The Brachial Plexus: Halstead applied the theory of local
anesthesia to peripheral nerves for surgery of the upper extremity,
defending its use in the scientific community and encouraging
others to discover its possibilities. A pupil of Halstead, Harvey
Cushing, published a report concerning its efficacy with regard to
avoiding complications of shock, comparing two surgeries on
the shoulder, one without cocainization and the other with
cocaine applied proximal to the division of nerve trunks [36].
The first percutaneous supraclavicular block was performed
in 1911 by German surgeon Diedrich Kulenkampff [1880-
1967] [37]. Later, Georg Hirschel [1875-1963] described a
percutaneous approach to the brachial plexus from the axilla
[38]. Livingston compiled a review of the achievements of the
time in 1927, stating, 'On the basis of strict comparison, it
cannot be said that the untoward effects from brachial plexus
block are of more severity than those of inhalation narcosis.
Furthermore, even in the experimental era, complications
and disagreeable by-effects occurred with only a small
percentage of patients, while the average patient receives the
brachial plexus anesthesia without unfavorable symptoms' [39].
Thus he opened the door for regional anesthesia as a less
harmful technique when compared with general anesthesia.
In 1928, Kulenkampff and Persky published a report about
a thousand blocks without apparent major complications.
The technique applied to the patient was described in that
they would be in the sitting position or in the supine position
with a pillow behind the shoulders. The needle was inserted
above the midpoint of the clavicle where the pulse of the
subclavian artery could be felt and it was directed medially
toward the second or third thoracic spinous process [40]. By
the late 1940s, clinical experience with brachial plexus block
in both peacetime and wartime surgery was extensive, and
new approaches to this technique began to emerge [41].
In 1946, F. Paul Ansbro was the first to describe a continuous
brachial plexus block technique. This was done by a needle being
secured in the supraclavicular fossa with tubing connected to
a syringe through which incremental doses of local anesthetic
could be injected [42]. The subclavian perivascular block was
first described by Winnie and Collins in 1964 [43]. This approach
became popular due to its lower risk of pneumothorax compared
to the traditional Kulenkampff approach.
The infraclavicular approach was first developed by Raj
in 1973 [44]. In 1977, Selander described a technique for
continuous brachial plexus block using an intravenous catheter
secured in the axilla [45]. The development of a more practical
and portable nerve stimulator [NS] in 1962, led to increased
use among practitioners. Reports questioning the safety of
the paresthesia technique such as those by Selander in 1979
encouraged clinicians to explore other approaches during the
last decade of the 20th century. In 1989, another modality was
introduced into clinical practice. Ting and Sivagnanatnam
utilized ultrasound to confirm needle placement and observe
local anesthetic spread during axillary nerve blocks [46].
'Today, upper extremity plexus blocks have an obvious
place as a sole anesthetic technique or as a powerful
complement to general anesthesia,
reducing the need for analgesics and hypnotics
intraoperatively, and providing effective postoperative pain
relief'.
Bier block [Intravenous Regional Anesthesia]: In August
1908 Karl August Bier, Professor of Surgery in Berlin, revealed
a new method of producing analgesia of a limb which he named
'vein anesthesia' [47].
Bier first presented this new method of intravenous regional
anesthesia [IVRA] at the 37th Congress of the German Surgical
Society on 22 April 1908, only 10 years after other significant
communication on spinal anesthesia [48]. The method consisted
of occluding the circulation in a segment of the arm with two
tourniquets and injecting a dilute local anesthetic through a
venous cut-down in the isolated segment. Bier used procaine, the
first safe injectable local anesthetic that had been synthesized by
Einhorn in 1900 [15].
After initial enthusiasm, the technique fell into obscurity
for >50 years. In 1963, Holmes reintroduced Bier block with the
novel use of lidocaine [49].
Today, intravenous regional anesthesia of the upper limb
remains popular because it is reliable, cost effective, safe, and
simple to administer.
Spinal and epidural anesthesia: The advent of spinal
anesthesia cannot be fully accredited to the arrival of cocaine
into the medical field. It served many purposes including
ophthalmology, treatment of depression by Sigmund Freud [50],
and even being added to Coca-Cola in 1886 [51]. The credit
should go to the clinicians who first attempted to apply this
drug to the spinal column. Procedures approximating the spinal
column were regarded by the scientific and medical community
as high risks with permanent paralysis being the result. However,
these pioneers went ahead and tested their hypotheses, changing
the field of anesthesiology and obstetrics.
Karl Gustav Bier [52], is credited with the first use of operative
spinal anesthesia on the lower limbs although James Leonard
Corning was the first to use cocaine in the spinal column in 1885
[53], several years earlier than Bier [48]. A native of Stamford,
CT, his family fled to Germany when he was a young boy. The
influence of German and French physicians influenced Corning's
curiosity. Upon returning to the United States, he began his
practice of Neurology in New York City, attending the
Roosevelt Hospital. Corning had been in the surgical
auditorium in 1884 when William Halstead and Richard Hall
successfully demonstrated one of their peripheral nerve blocks
[54]. A year later he first demonstrated spinal anesthesia by
injecting 2 ml of 3% cocaine into the T11/T12 interspinous
space in a gentleman suffering with "spinal weakness" and
"seminal incontinence". Minutes later the patient experienced
impaired sensitivity in the legs, genitalia and lumbar region as
well as post-dural puncture headache. The theory
published by him stated that the mechanism of anesthesia
was through the infusion of cocaine into the tissues
surrounding the spinal column and by diffusion into the venae spinosae. Because his procedure did not describe fully
penetrating the dura, he was not credited with being
responsible for the first spinal block. Bier's block did this in
1899, entering the spinal column fully and injecting less of the
cocaine solution to provide the anesthetic effects. He never
applied his findings in the operating room, but
he may have used this technique to relieve forms of paresthesia
in his own patients.
Despite the utility of spinal anesthesia, the preference of
spinal anesthesia for nerve blockade and lower extremity surgery
was secondary to general anesthesia because of the feared
neurologic sequelae.
One case report detailed paraplegia with two previously
healthy middle aged males [55,56].
In 1956, a study from the Hospital of the University of
Pennsylvania by Dripps and Vandam showed that a long term
follow up of over 10,000 patients who received spinal anesthesia
resulted in no long term neurologic sequelae [57].These findings
improved the public image of spinal blocks and their use in the
operating room and in pain clinics [58,59].
Caudal blocks and epidurals came into use in children much
later. In the early years these blocks were performed by surgeons,
but as other doctors began to give anesthetics the specialty
of anesthesia evolved, and these practitioners gradually took
over this role. On August 16, 1898, August Bier tried to induce
spinal anesthesia with cocaine. All of his six patients, including
two children - the first to have spinals - had postoperative
vomiting and headache, and Bier felt that the technique had little
advantage over general anesthesia. In 1909-1910,H. Tyrell Gray,
superintendent at the Hospital for Sick Children at Great
Ormond Street, London, published three detailed papers each
based on more than 100 cases of spinal anesthesia in children.
They occupied 14 1/2 pages in the Lancet [60].Gray's patients
were not anesthetized but were comforted by a nurse who knew
them. Some were even allowed to have cake! Six retched and 21
vomited during the anesthetic. The incidence of vomiting
postoperatively was very low, only 2%. In three patients, spinal
anesthesia failed, and general anesthesia was instituted. Gray
concluded that the benefits to the patient were as follows:
absolute anesthesia, no surgical shock, the analgesia was
localized to the area of the block, and postoperative vomiting
was minimal. The advantages for the surgeon were as
follows: good operating conditions, easy access to the
abdomen, the bowel was constricted, surgery could be
completed quickly, and the anesthetic could be administered
by the surgeon. Postoperatively, there was less pain, and
feeding could be started sooner. These papers illustrate how
much was known about spinal anesthesia in children, more
than 100 years ago.
Caudal blocks now play a major role in pediatric anesthesia,
but they were first reported for cystoscopies in children by
Meredith Campbell when she presented a paper to the American
Society of Regional Anesthesia in 1933 [61]. By 1950, Harry
Curwen in Durban, South Africa, was using caudal blocks in
neonates, he recognized the potential advantages, especially
for the occasional pediatric anesthetists or doctors working in
the rural areas [61]. Schulte Steinberg, who had trained
with Philip Bromage in Montreal, working in the county hospital
in Starnberg [Germany] used caudal anesthesia and
undertook studies on the dermatomal levels reached in
children, with different volumes of local anesthetic with
added X-ray contrast. Schulte Steinberg went on a sabbatical in
Durban, where caudal anesthesia was used commonly. He
studied caudal catheters in piglets and human cadavers and
found it was possible to thread them easily to the thorax in small
children [62]. Bosenberg then applied the method clinically in newborns with biliary atresia and subsequently found that
by using continuous infusions via caudal catheter, the need for
postoperative ventilation in babies with oesophageal atresia
and other surgical conditions was reduced. His work
demonstrated that epidural analgesia can be provided for
neonates undergoing major surgery with a low risk of
complication [63]. Further advantages include the reduced
need for muscle relaxants, opioids and postoperative
ventilatory support.
Spinal and other local anesthetic techniques in children had
ups and downs in popularity likely related to improvements in
general anesthesia.
Ultrasound Guidance: A technology originally used to detect
submarines during warfare, ultrasound found initial medical use
in fetal monitoring and identification of gallstones, but it would
take several decades before it was adopted to identify nerves.
In 1978 La Grange developed a unique approach of
delivering local anesthesia to the brachial plexus using Doppler
ultrasonography [58].
This type of ultrasonography only provided
unidimensional images and they reported no neurological
sequelae or pneumothorax. It did not become popular due
to the prohibitive cost of this technology. In 1989 Ting
described ultrasonographic visualization of local anesthetic
spread during brachial plexus block. Instead of Doppler, they
use a B-mode ultrasound device that provided twodimensional
visualization. Their conclusions emphasized
improved visualization of the brachial plexus but did not
comment on improved efficacy and safety.
In 1994, Kapral [64], reported a significant decrease in the
amount of anesthetic needed to produce clinical analgesia using
ultrasound guidance during brachial plexus block. Moreover,
the technique was associated with fewer complications, while
patients reported less discomfort. The stage was set for a
revolution in techniques used to identify neural structures that
could be blocked with local anesthetic agents. Improvements in
anesthetic techniques can bring about major changes in surgical
approaches. Ultrasound guided regional anesthetics have enabled
patients to emerge from minimally invasive day-surgery with
almost no pain or side effects.
Regional vs General Anesthesia: any improvement
in outcomes?: As in all fields of medicine, there has been an
explosive growth in clinical research related to regional
anesthesia. In 1987, Yeager [59] and colleagues showed a
dramatically reduced mortality in high-risk patients who
received regional anesthesia. In 2000, Rodgers and colleagues
published an extensive meta-analysis showing a reduction
in postoperative mortality and morbidity with neuraxial
anesthesia with the subsequent recommendation of more
widespread use of this technique [60].
Spinal anesthesia is the preferred anesthetic method for subumbilical
surgery, particularly in elderly patients and parturients.
Parker and colleagues [61], investigated in a Cochrane metaanalysis
22 clinical trials involving 2567 patients where
neuraxial [mainly spinal] anesthesia was compared with
general anesthesia for hip fracture surgery. The authors found
a reduced risk for postoperative deep venous thrombosis
[30% compared with 47%] and acute postoperative confusion
[9.4% compared with 19.2%] in patients treated with neuraxial [mainly spinal]
anesthesia compared with general anesthesia. There was no
evidence for reduced perioperative mortality. Peripheral nerve
blocks and local anesthesia have very few cardiovascular
or pulmonary side-effects. Complications do occur, and
peripheral nerve block must be performed with adequate
safety precautions by anesthetists with appropriate
experience. In experienced hands, it seems likely that
peripheral nerve block would be safer than general
anesthesia due primarily to the avoidance of airway
management. However, evidence to prove this assumption will
never be available due to the low numbers of severe anesthesiarelated
complications. At the same time opioid consumption can
be decreased or even avoided, in consequence, opioid-related
side-effects can be reduced when perineural block is performed.
Whether regional anesthesia influences outcome after surgery
is a controversial topic, in skilled hands, various regional
anesthetic techniques are powerful tools providing almost
perfect perioperative pain therapy. Using an optimal
balance between appropriate techniques, application of
advanced equipment, and optimal doses of drugs, regional
anesthesia plays an important role in perioperative medicine.
Conclusions
Regional anesthesia has a fascinating history, with events
following the introduction of general anesthesia by a halfcentury.
As with general anesthesia, techniques and drugs
have evolved over time, and currently many patients receive
concurrent care under both techniques. During the late
19th and early 20th century regional anesthesia was the
preferred technique because of complications associated
with general anesthesia, and a shortage of anesthesia
providers. Ensuing decades showed the use of regional
anesthetics decreasing as general anesthesia became safer.
However, recent advances in techniques, drugs and
applications have led to a resurgence in the use of regional
anesthesia. We believe historical aspects of regional
anesthesia can and should be taught as part of the
educational curriculum.
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