- Journal of Acupuncture and Meridian Studies

J Acupunct Meridian Stud 2015;8(1):30e39
Available online at www.sciencedirect.com
Journal of Acupuncture and Meridian Studies
journal homepage: www.jams-kpi.com
- RESEARCH
ARTICLE
-
Successful Practice of Electroacupuncture
Analgesia in Equine Surgery
Eldessouky Sheta 1,*, Safwat Ragab 2, Haithem Farghali 1,
Asmaa EL-Sherif 3
1
Department of Surgery, Anesthesiology and Radiology, Faculty of Veterinary Medicine,
Cairo University, Cairo, Egypt
2
Department of Anatomy and Embryology, Faculty of Veterinary Medicine, Cairo University,
Cairo, Egypt
3
Equine Division, Veterinary Military Hospital, Cairo, Egypt
Available online 24 July 2014
Received: May 27, 2014
Revised: Jul 12, 2014
Accepted: Jul 15, 2014
KEYWORDS
acupoints;
acupuncture;
analgesia;
electroacupuncture;
equine surgery
Abstract
Electroacupuncture analgesia was used for surgery in horses and donkeys. A KWD-808
electrical stimulator was used to incrementally induce a dense, dispersed wave output
at frequencies from 20 to 55 Hz, which was maintained at a frequency of 55 Hz, and to
change the amplitude of the wave to the best grading number for the suggested operation
in each animal. Induction of analgesia lasted for 20e30 minutes, and the effect of analgesia was maintained for 20e45 minutes depending on the type of surgery performed.
The exhibited clinical signs, physical examination data, and the responses of all animals
were used for evaluating the periods of analgesia. Although the majority of the cases
(95%) had no response to strong surgical pain, they experienced significant increases in
heart rates and respiratory rates during induction. The lack of pain, relaxed surgical procedures, reduced intraoperative bleeding, and improved healing without complications
were all definite benefits of using electroacupuncture analgesia in surgery. Thus, this
study has provided surgical evidence supporting the effectiveness of electroacupuncture
analgesia, as well as confirming its reliability, in the field of equine anesthesia and
surgery.
* Corresponding author. Department of Surgery, Anesthesiology and Radiology, Faculty of Veterinary Medicine, Cairo University, Cairo,
Giza 12211, Egypt.
E-mail: [email protected] (E.Sheta).
pISSN 2005-2901 eISSN 2093-8152
http://dx.doi.org/10.1016/j.jams.2014.07.002
Copyright ª 2015, International Pharmacopuncture Institute.
Electroacupuncture analgesia in equine surgery
1. Introduction
Veterinary acupuncture was initially practiced in China and
later spread to other Asian countries, such as Japan and
Korea, about 1500 years ago. In the last 25e30 years, there
has been a tremendous growth in animal acupuncture in
Europe and the United States [1]. Many types of stimulations, including acupuncture, various peripheral electrical
stimulations, vibrations, and electrical stimulations of
specific areas in the brain, are able to produce analgesic
effects [2]. They activate pathways from the brain to the
spinal cord and inhibit incoming pain information in various
layers of the dorsal horn of the spinal cord. These pathways
involve many neurotransmitters, including serotonin,
endogenous opiates, and norepinephrine [3]. Electroacupuncture has stronger effects than other types of
acupuncture [4], and acupuncture analgesia has been produced using different types of stimulations at both acupoints and nonacupuncture points [5]. Acupuncture has
been proven to be effective for treating pain, geriatric
diseases, and exercise-related diseases in horses [6], and
results of neuroscience studies have provided a physiological basis for explaining how acupuncture works and how it
stimulates the release of painkillers known as endorphins
[7]. The acupoints are located throughout the body on
meridians and are connected to each other. These points
can be stimulated by various means in order to produce
physiological functions to treat different diseases [8].
The current work was designed to prove the relevance of
electroacupuncture analgesia in the field of equine surgery.
The aim was to replace expensive anesthetic drugs with a
simple analgesia technique that could maintain the animal’s normal physiology during surgery without pain and
danger.
2. Materials and methods
The present investigation was carried out on 18 healthy
experimental animals (10 stallions and 8 mares); their ages
varied from 8 to 15 years, and their body weights ranged
from 350 to 450 kg. These horses were cared for and
managed during the 1-year study period in accordance with
the guidelines of the Animal Ethics Committee of Veterinary Medicine, Cairo University (Cairo, Giza, Egypt). Electroacupuncture stimulation was used for seven clinical
cases (2 foals, 1 gelding, 2 stallions and 2 donkeys) treated
at our surgery clinic. Surgeries on the head and neck, the
chest wall, the thigh, and the abdomen, as well as castration were performed on experimental animals. Each animal, whether clinical or experimental, had an independent
acupoints plan. The selected acupoints were exposed to
electroacupuncture stimulation throughout the duration of
the surgery.
An acupuncture electrostimulator set (9 V; KWD-808 I
Multi-Purpose Health Device) with a current frequency
range of 1.2e55 Hz made in China. Acupuncture needles of
different sizes (0.50 40 mm, 0.70 70 mm), and electric
wires with terminal clips were used in this study. The
electrostimulator was checked to ensure that the power
was switched off. Needles were inserted at the selected
acupoints at the appropriate angles and depths of insertion.
31
The electroacupuncture stimulator, which produced a bipolar waveform (þ), and () electrodes were connected to
the needles by electric wires with terminal clips. The power
switch was turned on to establish a frequency of 20 Hz at
the beginning, which took 10 minutes; the frequency was
then changed gradually for the next 10e20 minutes to
achieve a frequency of 55 Hz. Thereafter, for the maintenance of analgesia, the output with the 55-Hz frequency
was sustained, and the amplitude of waves was changed to
the required grade (from 1 to 10) of the outputs; the
analgesic effect was maintained until the end of the surgery. The duration of analgesia varied (from 20 to 45 minutes) depending on the type of surgery performed.
The exhibited clinical signs, particularly after electroacupuncture induction and maintenance, were shivering,
tremors, quidding, blinking of the eyelids, nystagmus,
abnormal tongue movement, sweating, engorgement of
facial blood vessels, muscle contraction, urination, and
defecation. The body temperature ( C), mucous membrane
color, respiratory rate (breaths/minute), heart rate (beats/
minute), and capillary refill time were evaluated before
electroacupuncture stimulation (control) and during induction and maintenance of analgesia.
Head and neck operations included cheek wound suturing (Fig. 1), neck wound suturing (Fig. 2), trephining
(Fig. 3), and excision of the medial canthus sarcoid (Fig. 4).
The acupoints used were bilateral and can be described as
Kuang-Xia-Kong (infraorbital foramen), Mian-Shen-Jing
(facial nerve), Ting-Gong (auditory palace), Yan-Chi (rock
pond), He-Xi (jaw stream) and Xia-Yi-Feng (lower wind
shield).
For lateral thoracic wound suturing, the acupoints
Qiang-Feng (robbing wind) SI-9 and Qi-Jia (withers) between GV-13 and GV-14 were used and are demonstrated in
Fig. 5. For the laparocolotomy, the acupoints Qi-Jia, BaiHui (hundred meetings), Wei-Gan (tail base) GV-2, and DaKua (greater trochanter) were used as shown in Fig. 6. For
thigh wound suturing, the acupoints Bai-Hui, Wei-Gan, DaKua, and Han-Gou (sweat groove) BL-37 were used. The
procedures are displayed in Fig. 7.
For the treatment of a lateral abdominal hernia in a foal,
the acupoints Bai-Hui, Wei-Gan, Da-Kua, Qiang-Feng, and
Tian-Men (heavenly gate) GV-16 were used and are shown in
Fig. 8. For the treatment of granulomatous swelling in the
right side of the abdominal wall in a foal, the acupoints QiJia, Bai-Hui, and Wei-Gan were used, with two needles
inserted parallel to both sides of the operation site. These
acupoints are shown in Fig. 9.
For the treatment of a long-standing fibroma at the right
thoracic wall in a donkey, the acupoints Tian-Men, Qi-Jia,
Bai-Hui, and Wei-Gan were used with two needles inserted
at both ends of the operation site. In addition, the auricular
acupoints Shen-Men (gate of mind), Fei-I, and Xiong (thorax
point) were used. These procedures are illustrated in
Fig. 10.
For the treatment of an obstructive urolith in the perineal urethra and rupture of the urinary bladder in a donkey,
the acupoints Hou-Hai (caudal sea) GV-1, Han-Gou, Da-Kua,
Wei-Gan, Bai-Hui, Qiang-Feng, and Tian-Men, with two thin
needles inserted at the incision extremities of the urethrostomy site, were used. These procedures are shown in
Fig. 11. For castration surgery, the acupoints Bai-Hui, Wei-
32
E. Sheta et al.
Figure 1 Cheek wound suturing: (A) deep cheek wound, (B) suturing procedures, (C) wound sutures, and (D) recovery of the
horse from analgesia.
Gan, Da-Kua, Qiang-Feng, and Tian-Men, in addition to
Duan-Xue (suspended pivot) GV-5, were used. These procedures are shown in Fig. 12.
After surgery, the power was switched off and the needles were removed. All data were collected and evaluated
statistically using an ordinary analysis of variance with the
GraphPad prism package program and the Student t test [9]
with the help of Office Excel package 2007.
3. Results
All the previously mentioned clinical signs were observed
during electroacupuncture induction. On physical examination before performing the electroacupuncture
Figure 2
stimulation, the experimental horses showed normal
values. During induction, a few minutes following the start
of stimulation, all horses showed signs of mild stress,
including dilated pupils and significant increases in their
heart rates [mean (M) standard error (SE):
63.166 4.301] and respiration rates (M SE:
24.333 2.123). They were still conscious and could eat or
drink; in addition, their sight and hearing were normal.
Pupillary dilation and salivation occurred in three experimental horses (approximately 17%), which indicated pain in
the internal organs and was counteracted by increasing the
frequency of the acupuncture analgesia stimulus. At the
induction phase, the operation site was tested for analgesia
using needle pricks. At first, full sensitivity to pain was
present. After 10e15 minutes, the response to the stimulus
Neck wound suturing: (A) twitching of the horse, (B) deep neck wound, and (C) suturing procedures.
Electroacupuncture analgesia in equine surgery
Figure 3
sinus.
33
Trephining steps: (A) circular skin incision, (B) exposed periosteum, (C) trephine of bone disc, and (D) exposed frontal
decreased. After 20e30 minutes, in 95% of the cases, the
horses showed no response to strong pain stimuli in and
around the operation site; at that time, the operation was
begun. During maintenance, the ears in all horses were
alert and moving. The horses voided variable amounts of
urine, particularly at the end of surgery. During each surgery, a sufficient amount of manure was defecated by the
animals as moist balls and not as dry or loose material.
Insignificant increases in heart rates (M SE:
36.823 1.906) and respiratory rates (M SE:
13.704 0.839) were recorded during maintenance, as
shown in Fig. 13.
At the time of induction, the horses showed a degree
of discomfort or pain, which was substantiated by restlessness, defensive reactions, and struggling. The amplitude of the output was then reduced to a strong, but
Figure 4 Excision of the medial canthus sarcoid: (A) sarcoid growth, (B) stimulated acupoints, (C) sarcoid excision with
cauterization of bleeders, and (D) recovery after 1 month.
34
E. Sheta et al.
Figure 5 Suturing of a lateral thoracic wound: (A) stimulated acupoints, (B) induced skin wound, (C) sutured skin wound, and (D)
wound sutures.
Figure 6 Laparocolotomy procedures: (A) stimulated acupoints, (B) incised skin in left flank, (C) completed laparotomy, (D)
exteriorized small colon and colotomy, (E) closure of colon incision, and (F) closed abdominal wound.
Figure 7
Thigh wound suturing: (A) suturing of the tensor fasciae latae and (B) closure of skin wound.
Electroacupuncture analgesia in equine surgery
35
Figure 8 Herniorrhaphy procedures in a 1-year-old foal: (A) stimulated acupoints, (B) incised skin, (C) blunt dissection, (D)
exposed jejunal loop, (E) closure of abdominal muscles and s/c, and (F) sutured skin subcutaneous tissue (s/c or sub/cutis).
acceptable, level so that it could be tolerated by the
animal without any obvious discomfort. Excessive stimulation led to a reduction in the electroacupuncture analgesic effect and struggling. Severe muscular convulsions
with rigidity, followed by conversions to a flaccid muscle,
were observed at the end of this phase and throughout
the maintenance period. During testing, skin nociceptors
were present in four (approximately 22%) horses that
underwent surgery, but their effects were eliminated
using an injection of a local infiltration anesthesia (2%
lidocaine) at the intended line of incision. The intraoperative bleeding was less than expected. The responses
of experimental horses to electroacupuncture stimulation
are summarized in Fig. 14; only one horse (approximately
6%) exhibited various degrees of discomfort manifested by
restlessness and struggling.
All surgical and clinical cases exhibited excellent degrees of response to the induced electroacupuncture
analgesia. Healing of surgical wounds in both experimental
and clinical cases was adequate and without complications.
The sutures were removed 10 days after the surgery.
4. Discussion
Various anesthetic regimens have been used for major and
minor equine surgeries, but none has proven to support the
physiological vitality of the animal or to have no side effects. Therefore, we directed our attention toward the use
of electroacupuncture stimulation to produce surgical
analgesia. The device for electrical stimulation, which is
used for humans, in general, and used in the present study
for the production of electroacupuncture analgesia, proved
to be safe and adequate and prevented serious electrolytic
lesions during surgery.
Electrical stimuli were induced through the acupuncture
analgesia points in the peripheral sensory nerves to the
spinal cord. The stimuli reached the midbrain through the
Figure 9 Excisions of granulomas in the right flank of a 2-year-old foal: (A) multiple granulomas, (B) incised skin, and (C)
completed surgical excision.
36
E. Sheta et al.
Figure 10 Excision of right-thoracic-wall fibromatous swelling in a 9-year-old donkey: (A) fibromatous swelling, (B) stimulated
acupoints, (C) blunt dissection, (D) excised fibromatous mass, and (E) sutured skin wound.
ascending spinothalamic tracts. In the midbrain, the
ascending signals caused release of endorphins, serotonin,
and other neurotransmitters, which activated a descending
inhibition mechanism and prevented the pain signals from
the surgical area from reaching the cerebral cortex. The
electroacupuncture analgesia enabled the surgeon to
perform the surgery without any complications and
discomfort for the animals. Before performing the surgery,
the animals were properly restrained and acupuncture
needles were inserted to the correct depths; output leads
were not connected across the thorax to reduce the risk of
cardiac arrest. The surgery was then performed in equines
and other animals under electroacupuncture analgesia,
which was the sole analgesic agent [10].
Electroacupuncture stimulation at 55 Hz had a longlasting effect and produced analgesic effect for the
aforementioned operations. In addition, the degree of
analgesia diminished if the frequency was not changed
every 20 minutes; this coincided with the results presented
by Luna [11]. However, on pain testing, approximately 22%
of the horses had suffered a stroke of the tissue forceps
during skin suturing, which might have been due to the
nociceptors that remained during acupuncture analgesia;
injection of 2% lidocaine at the incised wound’s lips suppressed the effect of these nociceptors and facilitated suturing. When more acupoints were involved during
acupuncture stimulation, there was a stronger analgesic
effect [12].
Electroacupuncture causes release of b-endorphin and
adrenocorticotropic hormone (ACTH) from the pituitary
gland. ACTH induced the release of cortisol from the adrenal glands. The blood cortisol levels of the horses were
significantly increased after 30 minutes of electroacupuncture treatment [13]. The release of endogenous
opioids was consistent with acupuncture analgesia [12] and
was potentiated by D-phenylalanine, which inhibited
enkephalinase-mediated degradation of enkephalins and
endorphins [14]. However, the opioid antagonist naloxone
was able to reverse the effect of acupuncture analgesia in
animals [15].
Activation of nociceptors increased the rate of glucose
consumption in the superficial part of the dorsal horn of the
spinal cord. Low-frequency electrical stimulation produced
a relative decrease in the rate of glucose consumption.
Electroacupuncture analgesia in equine surgery
37
Figure 11 Urethrostomy and abdominal catheterization in a 6-year-old donkey: (A) uroperitoneum on an ultrasonographic image,
(B) stimulated acupoints, (C) surgery sites, and (D) the exteriorized urolith.
However, morphine diminished this increase in glucose
consumption and potentiated the analgesic effect [16].
Acupuncture analgesia induced its effect through
neuronal mechanisms associated with the central nervous
system [17,18], as well as through the mechanism of
endogenous opiates and their receptors, such as endorphin,
enkephalin, endomorphin, and dynophin, which were reported to be frequency-dependent factors [19,20]. The DeQi or De-Chi was distinguished by the cortex during
acupuncture needling; thus, cortical involvement followed
acupuncture stimulation [21,22].
Inflammation induced a state of hyperalgesia and, in
turn, decreased the pain threshold. Acupuncture regulated
this state of hyperalgesia and reduced the degree of pain.
Acupuncture therapy was used not only to relieve pain but
also to treat various medical conditions [23,24]. Injured
neurons expressed more peptides (substance P, somatostatin, and calcitonin geneerelated peptide) to induce
neuronal plasticity, but with persistent inflammation,
hyperalgesia was evolved [25]. Acupuncture had an antihyperalgesic effect in inflammatory animal models [26].
Electric stimulation of the peripheral nerve elicited an
analgesic effect [27]. Intermittent electric stimulation was
a valid way to prevent the occurrence of tolerance to
acupuncture analgesia [28].
Serotonin (5-hydroxytryptamine) was an analgesic
transmitter. The effect of serotonin was diminished after pchlorophenylalanine (serotonin synthesis inhibitor) injection. Thus, serotonin levels increased in the spinal cord and
enhanced electroacupuncture analgesia at 2 Hz [29]. The
binding of serotonin to its receptor activated the inhibitory
interneurons in the spinal cord, which contained enkephalin. Enkephalin and opioid receptors were thought to play
important roles in inhibiting pain-sensation signals [18].
High-frequency electroacupuncture decreased the concentration of serotonin within the cortex, and therefore
acted as a sedative [30]. The arcuate nucleus of the hypothalamus activated the periaqueductal gray mediated by
Figure 12 Procedures for castration in 5- and 6-year-old stallions: (A) stimulated acupoints, (B) exposed testicles, and (C)
completion of bilateral ablation of testicles.
38
Figure 13 Physical characteristics of the experimental
horses before induction, during induction, and during maintenance of electroacupuncture analgesia.
b-endorphin. The activities of periaqueductal gray were
fired by the actions of b-endorphin and enkephalin, but not
by dynorphin in low-frequency electroacupuncture analgesia [31].
Analgesic effect was produced using various forms of
stimuli, which activated pathways from the brain to the
spinal cord and inhibited incoming pain information in
various layers of the dorsal horn of the spinal cord [3]. The
produced surgical analgesia was maximized in the first 1e2
hours subsequent to electroacupuncture stimulation and
was indicative of neurohumoral mechanisms during the
period of analgesia, as reported by Han [32].
The technical points necessary to achieve an acceptable
analgesic effect in equine surgery were the manner of
securing the horse; blindfold application; reduction of
noise, movement, and excitement; and prevention of kicks
using the Wei-Gan acupoints. The positive electrode was
connected to collateral (auxiliary) acupoints, and the
negative electrode was connected to the principle acupoints to adjust the electrical circuit at the operation site.
However, in some operations when pain stimuli exceeded
the analgesia, a pain response was manifested by the animals during incision and suturing of the skin or peritoneum.
To solve this problem, the frequency or output voltage was
E. Sheta et al.
changed to an acceptable level, which was normally sufficient to counteract the pain; however, sometimes a small
amount of local anesthetic solution was sprayed on or
injected into the surgery areas. The use of local infiltration
at the intended line of incision was needed in less responsive horses (22% of the cases) to complete the surgery.
The choice of acupoints for acupuncture analgesia
depended on the operation site and the experience of the
veterinarian. Different acupoint combinations were effective, and no one combination was determined to be satisfactory by all the authors. Different combinations of
acupoints have been used in various horse operations. Examples of acupoint combinations used in this work were
Bai-Hui, Wei-Gan, Duan-Xue, and Tian-Men; these points
were located on the midline from the first cervical to the
last sacral vertebra. Points for abdominal and hind limb
operations were the acupoints mentioned earlier along with
Da-Kua. Points for chest operations were Qian-Feng, Qi-Jia,
and Tian-Men, and other points on or near the spinal nerves
supplying the operation site were added. In addition, two
paraincisional points were used in all horses operated under
electroacupuncture stimulation. The long needles never
impeded access to the operation site as they were placed
apart from each end of the incision. Electroacupuncture
stimulation at a frequency of 20e40 Hz was preferred at
the start of operation, and the frequency was increased
afterward. Auricular electroacupuncture was not helpful in
producing the analgesic effect, as it did not result in
increased endorphin levels in the animal’s plasma as reported by Pert et al [33].
This work has provided surgical proof for the relevance
of electroacupuncture in the production of equine analgesia. Furthermore, it confirmed electroacupuncture as a
suitable method to produce surgical analgesia in the field of
equine anesthesia and surgery.
Disclosure statement
The authors declare that they have no conflicts of interest
and no financial interests related to the material of this
manuscript.
Acknowledgments
The facilities and finances for this research provided by
Cairo University Grants for veterinary research are gratefully acknowledged (Ethical committee number: Cu F Vet/
F/SUR/2014/26).
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