Written by a Medical Acupuncture for Veterinarians Course Graduate. Author’s name available upon request. Signed release obtained from client/author/4926.
In excessive climatic conditions, the inability of the equine sweat glands to function properly is often diminished. Sweat glands become desensitized to ß-adrenergic receptors over time. To restore optimal function of the nervous system acupuncture was performed in efforts to encourage neurovascular communication with the glands. Harmony’s treatment for anhidrosis included an array of acupuncture points to promote sweating, increase blood flow to the periphery, and create a more homeostatic environment within the body. Following acupuncture treatments combined with supplements and environmental alterations, she began to sweat more consistently. Acupuncture can be an effective form of treatment for anhidrosis when used in conjunction with other traditional remedies.
Harmony, a 17.5-year-old, Halflinger paint mare, presented with a chief complaint of anhidrosis for the past three summers. Other concurrent diagnoses include obesity and metabolic disease. She has a history of Degenerative Joint Disease (DJD) bilaterally in her hocks, secondary to metabolic disease. No joint injections were administered. Prior to presentation, she was on the following supplements: ½ scoop electrolytes two times per day, 2 scoops of One AC two times per day, ½ Guinness beer daily, equiwinner patches, 15 minutes of cool hosing and fans. Harmony is currently being ridden as a ground therapy and trail riding horse.
Physical Examination and Clinical Assessments
Upon physical examination, Harmony was bright and alert. All vital parameters were within normal limits. No abnormal findings noted on neurologic evaluation. No gait abnormalities appreciated on the lameness examination. She was consistently responsive on myofascial palpation at BL-11 bilaterally and BL-54 primarily on the left side.
Medical Decision Making
Anhidrosis is defined by the inability to sweat, caused by a failure in the secretory process of the glands. The main stimuli of the body to produce sweat are via an increase in environmental temperature and exercise. Although to date, sweat glands are not considered innervated, it is important to note the close proximity of sympathetic innervation to the rich blood supply surrounding the equine sweat gland. Axons reside close to capillaries and other vasculature and are able to sense a change in temperature. The initial vasodilatory reflex response to an elevated body temperature leads to withdrawal of vasoconstrictor tone. This response is followed by a powerful compensatory decrease in vascular tone involving the release of neurotransmitters from the sympathetic nerves, such as adrenaline acting on ß2 adrenoreceptors. In climatic stress specifically, the ß2 adrenergic receptors have become desensitized or downregulated to increased circulating adrenaline, which in turn leads to a refractory condition within the sweat gland.
One way in which acupuncture can be effective in restoring a homeostatic environment to the autonomic nervous system, includes its effect on adrenergic receptors in the periphery. The axon reflex that is initiated following stimulation of the nervous system calls for a peripheral signal to travel the length of the neuronal cell body and allow for antidromic activity affecting surrounding connective tissue. There is still discrepancy on which catecholamines are released locally and have their effect on decreasing vascular tone. Secondary to their vasodilatory action, coupled with withdrawal of noradrenaline, a potentiated release of bradykinin and other neurotransmitters, such as Nitrous Oxide are released. These neurotransmitters play a major role in further local cutaneous vasodilation. The ability of the patient to sweat correlates with the cutaneous blood supply, which is upregulated by modulating the parasympathetic and sympathetic nervous systems via acupuncture; this in turn leads to a more homeostatic environment. Both the local and peripheral effects of acupuncture are essential to anhidrosis. During exercise, about 70% of heat dissipation occurs via sweating, while the remaining heat is alleviated by respiratory tract evaporation. Therefore, many of the points used during this specific treatment course for anhidrosis were also targeted to benefit optimal pulmonary function to aid in more efficient cooling of the equine patient.
Harmony’s treatment course was initiated by stimulating the cervicothoracic spinal nerve at GV-14 to alter immunologic dysfunction, as well as influence appropriate respiratory mechanisms to aid in cooling. BL-11 was used to influence the cervicothoracic spinal nerve and decrease tension along this channel to ensure optimal function of the respiratory system. The caudal thoracic spinal nerve at BL 20 was also needled for the same reasons. She was consistently responsive to palpation of BL-23, governed by the thoracolumbar spinal n., indicating a degree of lumbar and pelvic pain. Electrical stimulation was performed bilaterally from BL-11 through BL-23. The mid-to-caudal lumbar spinal n. was influenced at Bai Hui for endorphin release and secondary pelvic limb pain, from previously diagnosed DJD bilaterally in hocks. In close proximity to the lumbar spinal nerves, Shen-shu, Shen-jiao, and Shen-peng were stimulated by electrical stimulation to aid in local lumbosacral and hindquarter pain relief. Severe sensitivity and discomfort was appreciated at BL-54 upon musculoskeletal palpation. The master point of the hindlimb is innervated by the cranial gluteal n. and dorsal rami of sacral spinal n., which were stimulated for relief of hip and gluteal pain. BL-40 and SP-6 innervated by the tibial n. were targeted for pelvic limb dysfunction and pain. LI-11 (radial n.) and ST-36 (fibular n.) were needled for immunomodulation and anti-inflammatory actions. To directly promote sweating the radial n. was stimulated at LI-4 and the tibial n. at KI-7 for the regulation of water retention and anhidrosis. LR-3 was treated via acupuncture and acupressure by the owner for stagnation of blood flow. Harmony received a total of three treatments starting at two week intervals and progressing to four.
Outcomes and Discussions
Following the first treatment this summer, the owner reported that Harmony began to sweat a minor amount more than she had prior to acupuncture. With the second and third round of acupuncture treatment she became more consistent in her sweating and was no longer tachypneic. The latter treatment was toward the end of the summer, when the environmental temperature had decreased. In addition to acupuncture treatment, she was also on a Herbsmith Summer Heat formula, electrolytes, One AC, and Guinness beer daily. Environmental management was altered with fans and cooling protocols daily. No adverse side effects were noted from the acupuncture treatments. This case study has reinforced the importance of integrating all forms of medicine to treat the patient. There are still many unanswered questions on the pathophysiology of this disease. Though much research has been done on this condition, further investigation is warranted to produce an effective evidence-based treatment for anhidrosis.
Jenkinson, David McEwan, Hugh Y Elder, and Douglas L. Bovell. “Equine Sweating and Anhidrosis Part 1: Equine Sweating.” Veterinary Dermatology 17.6 (2006): 361-92. Web.
Jenkinson, David McEwan, Hugh Y Elder, and Douglas L. Bovell. “Equine Sweating and Anhidrosis Part 2: Anhidrosis.” Veterinary Dermatology 18.1 (2007): 2-11. Web.
Robinson, Narda. “One Health SIM.” Medical Acupuncture for Veterinarians. Proc. Of Large Animal Equine Acupuncture, Colorado Denver. (2016). Print.