Erotic asphyxiation (variously called asphyxiophilia, hypoxyphilia or breath control play) is the intentional restriction of oxygen to the brain for the purposes of sexual arousal. The term autoerotic asphyxiation is used when the act is done by a person to themselves. Colloquially, a person engaging in the activity is sometimes called a gasper. Erotic asphyxiation can lead to accidental death due to asphyxia. The erotic interest in asphyxiation is classified as a paraphilia in the Diagnostic and Statistical Manual of the American Psychiatric Association. Physiology
Concerning hallucinogenic states brought about by chronic hypoxia, Dr. E. L. Lloyd notes that they may be similar to the hallucinations experienced by climbers at altitude. He further notes that no such state occurs in hypoxia brought about by sudden aircraft decompression at altitude. These findings suggest to him that they do not arrive purely from a lack of oxygen. Upon examining the studies on hypoxia he found that "abnormalities in the cerebral neurochemistry involving one or more of the interconnected neurotransmitters, dopamine, serotonin, and beta-endorphin had been reported in all the conditions associated with hallucinations." History
Historically, the practice of autoerotic asphyxiation has been documented since the early 17th century. It was first used as a treatment for erectile dysfunction. The idea for this most likely came from subjects who were executed by hanging. Observers at public hangings noted that male victims developed an erection, sometimes remaining after death (a death erection), and occasionally ejaculated when being hanged.
Anasarca is a severe and generalized form of edema, with subcutaneous tissue swelling throughout the body. Unlike typical edema, which almost everyone will experience at some time and can be relatively benign, anasarca is a pathological process reflecting a severe disease state and can involve the cavities of the body in addition to the tissues. Signs and symptoms
Physical appearance
Can include:

Periorbital edema "eye puffiness"
Perioral edema
Upper extremity edema
Ascites
Lower extremity edema
Pre-tibial edema
Pedal edema

Physical manifestations
Can include:

Impaired vision, difficulty opening eyes
Shortness of breath (SOB), dyspnea on exertion (DOE), orthopnea
Chest pain
Extreme discomfort
Debilitation

Cause
Anasarca is often caused by a decreased oncotic pressure. Organ failure
Liver failure
Kidney failure
Right-sided heart failure

Malignancy
Diet
Severe protein deficiency

Systemic manifestations of
Nephrotic syndrome
Protein-losing enteropathies
Capillary leak syndrome

In utero
In Hb Barts, the high oxygen affinity results in poor oxygen delivery to peripheral tissues, resulting in anasarca. Iatrogenic
It can also be caused by the administration of exogenous intravenous fluid. Diagnosis
Anasarca is a diagnosis made clinically and differentiated from edema by extent of body involvement and severity. Whereas edema is usually graded on a mild/moderate/severe scale and usually affects one or two regions of the body, anasarca affects the entire body and is the most severe form of edema, with subcutaneous tissue swelling from head to feet. Testing
Although there is no definitive test to prove anasarca, many tests can be useful to aid in the diagnosis. Anasarca is most often seen in conjunction with a low level of albumin
Recent studies have demonstrated a linkage between low-voltage electrocardiogram (ECG) (LVE) (QRS complexes of <5 mm in the limb and <10 mm in the precordial leads) and Anasarca.