As such, shock is a runaway condition of homeostatic failure, where the usual corrective mechanisms relating to oxygenation of the body no longer function in a stable way. When it occurs, immediate treatment is critical in order to return an individuals metabolism into a stable, self-correcting trajectory. Otherwise the condition can become increasingly difficult to correct, surprisingly fast, and then progress to a fatal outcome. In the particular case of anaphylactic shock, progression to death might take just a few minutes. Initial
During the Initial stage (Stage 1), the state of hypoperfusion causes hypoxia. Due to the lack of oxygen, the cells perform lactic acid fermentation. Since oxygen, the terminal electron acceptor in the electron transport chain, is not abundant, this slows down entry of pyruvate into the Krebs cycle, resulting in its accumulation. The accumulating pyruvate is converted to lactate (lactic acid) by lactate dehydrogenase. The accumulating lactate causes lactic acidosis. Compensatory
The Compensatory stage (Stage 2) is characterised by the body employing physiological mechanisms, including neural, hormonal, and bio-chemical mechanisms, in an attempt to reverse the condition. As a result of the acidosis, the person will begin to hyperventilate in order to rid the body of carbon dioxide (CO2). CO2 indirectly acts to acidify the blood, so the body attempts to return to acid–base homeostasis by removing that acidifying agent. The baroreceptors in the arteries detect the hypotension resulting from large amounts of blood being redirected to distant tissues, and cause the release of epinephrine and norepinephrine.
Baastrups sign is an orthopedic and radiographic disorder that often occurs in elderly humans. It is characterized by enlargement of the posterior spinous processes of the lumbar spine, with normal intervertebral disc height and neuroforamina. The reason it is referred to as kissing spine is because the posterior spinous processes kiss and touch one another as the individual goes into lumbar extension, for example when flat on their stomach. The condition has been seen in humans,  canines, particularly with boxer breeds, and certain breeds of horses. This disorder is named after Christian Ingerslev Baastrup. Diagnosis
The salient feature of the disorder is the exuberant osteophytosis that occurs at posterior lumbar spinous processes. Osteophytes are coarse calcifications at the edges of bone that form due to repetitive stress and trauma. There is also atrophy and fatty replacement of paraspinal musculature, which can be detected by CT or MRI. Treatment
The malpositioning seen on radiography may not cause any symptoms at all. If there are related symptoms, however, therapeutic options include chiropractic care, physical therapy and nerve block injections. As a last resort, decompressive laminectomy may be attempted to relieve pain symptoms and remove the abnormally enlarged portions of bone. References


== External links ==