Exsanguinate

Exsanguinate (pronounced eks-sang-gwuh-neyt)

(1) To kill by means of blood loss.

(2) To die by means of blood loss.

(3) To drain a body (living or dead) of blood.

1610–1620: From the Late Latin exsanguinātus (bloodless, deprived of blood), past participle of exsanguināre, the construct being ex- (out) + sanguinem, from sanguis (blood).  The construct in English was ex- + sanguine, + -ate.  The ex- prefix was from the Middle English, from words borrowed from the Middle French, from the Latin ex (out of, from), from the primitive Indo-European eǵ- & eǵs- (out).  It was cognate with the Ancient Greek ἐξ (ex) (out of, from), the Transalpine Gaulish ex- (out), the Old Irish ess- (out), the Old Church Slavonic изъ (izŭ) (out) & the Russian из (iz) (from, out of).  The “x” in “ex-“, sometimes is elided before certain constants, reduced to e- (eg ejaculate).  Sanguine was from the Middle English sanguine, from the Old French sanguin, from the Latin sanguineus (of blood), from sanguis.  The Latin sanquis, perhaps surprisingly, is of uncertain origin but may be from the primitive Indo-European hsh-én- from hésh₂r̥ (blood).  The suffix -ate was a word-forming element used in forming nouns from Latin words ending in -ātus, -āta, & -ātum (such as estate, primate & senate).  Those that came to English via French often began with -at, but an -e was added in the fifteenth century or later to indicate the long vowel.  It can also mark adjectives formed from Latin perfect passive participle suffixes of first conjugation verbs -ātus, -āta, & -ātum (such as desolate, moderate & separate).  Again, often they were adopted in Middle English with an –at suffix, the -e appended after circa 1400; a doublet of –ee.  Exsanguinate & exsanguinating are verbs, exsanguinated is a verb & adjective, exsanguination is a noun; the noun plural is exsanguinations.

As an adjective, exsanguine (bloodless) is attested from the mid-seventeenth century in both literal and figurative use and is now probably a technical word used only by embalmers, in clinical pathology, in the veterinary sciences or in slaughterhouses.  The word being a bit cumbersome, use never extended to kitchens, despite much exsanguination historically being part of the workings of production kitchens (before modern supply chains); where required, chefs prefer the punchier “drain”.  In use the verb is intransitive in the sense of “to die by means of blood loss” and transitive in the sense of “to kill by means of blood loss” or “to drain a body (living or dead) of blood”.

Gory: Lindsay Lohan was photographed in 2011 & 2013 by Tyler Shields (b 1982) in sessions which involved knives and the depiction of blood.  The shoot attracted some attention and while the technical achievement was noted, it being quite challenging to work with blood (fake or real) and realize something realistic but it was also criticized as adding little to the discussion about the pornography of violence against women.  There was a time when such photographs would has shocked but that moment has long passed and the most thoughtful comments on the photographs were that while it's a necessary discussion, it's one that should be conducted with words and such staged images do nothing but add to cultural desensitization.

Technical notes on the process of stunning & exsanguination in a slaughterhouse.  Department of Animal Biosciences, University of Guelph, Ontario, Canada.

(1) Stunning process

Criteria for a good slaughter method:

(1) Animals must not be treated cruelly or unnecessarily stressed.

(2) Exsanguination must be as rapid and as complete as possible.

(3) Damage to the carcass must be minimal, and the method of slaughter must be hygienic, economical and safe for abattoir workers.

To avoid the risk of cruelty, animals must be stunned or rendered unconscious before exsanguination.  When religious reasons do not allow stunning, extra care is needed to ensure exsanguination causes the minimum of distress to the animal.  In the Kosher method of killing, conscious cattle are suspended with the head stretched back, and then the throat and its major blood vessels are severed. Drugs cannot be used in the meat industry to induce unconsciousness in animals for slaughter because unacceptable residues would remain in the meat.

Animals can be effectively stunned by concussion which may be induced by a bullet or a bolt that penetrates the cranium or by the impact of a fast-moving knocker on the surface of the cranium.  In modern abattoirs, the primitive pole-axe has been replaced by devices which use expanding gas, either from an air-compressor or a blank ammunition cartridge. First, the animal is restrained in a narrow pen or knocking box in order to minimize its head movements, then the concussion instrument is then accurately located at a point on the midline of the skull, above the level of the brow ridges of the eye sockets.  Concussion stunning should not be applied on the neck or posterior part of the skull.

The knocker is a heavy instrument held with both hands.  There is a safety catch on the handle, but the actual trigger protrudes from the head of the knocker and is activated as the knocker is tapped against the animal's head.  The captive bolt pistol resembles a heavy hand gun but a blank cartridge rather than a bullet is used to propel a cylindrical bolt into the skull.  After penetration, the bolt is withdrawn into the barrel of the pistol and the pistol is reloaded.  Steers, heifers and cows are normally stunned with a knocker or a heavy captive bolt pistol, but bulls and boars which have massive skulls are sometimes shot with a rifle bullet. Pigs and lambs may be stunned with a light-weight captive bolt pistol.

Thirsty work.  A vampire exsanguinates.

(2) Exsanguination process

Cattle and pigs are usually exsanguinated by a puncture wound which opens the major blood vessels at the base of the neck, not far from the heart (the trade name for this process is sticking).  In sheep, lambs and small calves, the major blood vessels may be severed by a transverse cut across the throat, near to the head.  Poultry can be exsanguinated with a diagonal cut from the corner of the jaw towards the ear on the other side, or by a knife thrust through the roof of the mouth to severe the brain and its major blood vessels. For poultry, the cut may be made on the side of the head if the head is later to be removed automatically by machine.

If the sticking wound is inaccurately placed, exsanguination may be too slow, and it may be almost halted by the formation of large blood clots.  The formation of blood clots is accelerated when large areas of tissue are damaged by repeated inaccurate punctures.  If the trachea is severed by the sticking wound, blood may be drawn into the lungs as the animal breathes. Later in the slaughter procedure, this may necessitate the trimming of blood clots from the pleural membranes after they have been inspected.  If the oesophagus is severed, the vascular system may be contaminated by the entry of food particles into the venous system. If the connective tissues of the shoulder are opened, blood may seep into the shoulder region to form blood clots between the muscles.

Incomplete exsanguination increases the amount of residual blood in the carcass.  The lean meat may then appear unduly dark and the fat may become streaked with blood. On the surface of incompletely exsanguinated poultry, the skin may appear dark and bloody over the breast, neck, shoulders and wings. The microscopic tissue damage that may later be caused by the freezing and thawing of poultry enables residual blood to leak from skin capillaries.  Thus, the results of incomplete exsanguination are often more noticeable to the consumer than to the producer.

The exsanguination or sticking of meat animals in an abattoir is usually performed by severing the carotid arteries and the jugular vein at the base of the neck.  In poultry, these vessels may be cut only on one side of the neck. The sticking knife must be kept clean otherwise bacteria might be introduced into the venous system and spread through the otherwise relatively sterile muscles of the carcass.  Once exsanguination has started, the pulse and mean blood pressure decline rapidly because of the reduced stroke volume of the heart. Blood pressure changes are monitored physiologically by baroreceptors in the carotid sinuses. During exsanguination, respiratory movements of the thorax may be stimulated, and neurogenic and hormonal mechanisms attempt to restore the blood pressure by increasing the peripheral resistance by vasoconstriction.  The heart keeps beating for some time after the major blood vessels are emptied, but stops rapidly if exposed and cooled.  Electrical stunning of pigs may terminate cardiac activity so that, at the start of exsanguination, the blood escapes by gravity rather than being pumped out.  In pigs, cardiac arrest does not affect the rate and extent of exsanguination.  After exsanguination has started, the heart usually re-starts and attempts to pump, until it runs out of energy. Thus, in many cases, there is no reason why animals such as pigs and sheep cannot be killed by electrocution rather than being merely electrically stunned.  In cattle stunned by concussion, more or less complete exsanguination may be obtained without ventricular pumping. Similarly, normal exsanguination is obtained in poultry that have been killed by electrocution rather than by being electrically stunned. In meat animals, "head to back" stunning may be used to stop the heart.

Blood loss as a percentage of body weight differs between species: cows, 4.2 to 5.7%; calves, 4.4 to 6.7%; sheep, 4.4 to 7.6%; and pigs, 1.5 to 5.8%.  Blood content as a percentage of live weight may decrease in heavier animals since the growth of blood volume does not keep pace with growth of live weight. Approximately 60% of blood is lost at sticking, 20-25% remains in the viscera, while a maximum of 10% may remain in carcass muscles. Different stunning methods may modify the physiological conditions at the start of exsanguination and, also, the neural responses to exsanguination.  Electrically stunned sheep lose more blood than those stunned with a captive bolt, but they also have more blood splashes in their carcasses.

Reduction of blood flow to the kidneys causes the release of a proteolytic enzyme, renin, which acts on a plasma protein to produce a polypeptide, angiotensin I.  This polypeptide is converted enzymatically to angiotensin II which then causes widespread vasoconstriction. Vasoconstriction is important because it decreases the retention of blood in meat. Angiotensin II vasoconstriction is operative in both conscious and anaesthetized animals.  Catecholamines and antidiuretic hormone (ADH) may also enhance vasoconstriction during exsanguination.  Speed of exsanguination may modify the balance between neural and hormonal vasoconstrictive mechanisms, with hormonal vasoconstriction predominating in rapid exsanguination.  However, asphyxia prior to exsanguination may result in vasoconstriction due to the activity of the sympathetic nervous system.

Traditionally it has been maintained that poor bleeding leads to dark meat with poor keeping qualities due to microbial spoilage and rancidity but there is little scientific evidence in support of this view and it may be false, even in animals which retain massive amounts of blood in their carcasses.  Delayed exsanguination of cattle may lead to a slight reduction in the amount of blood removed so that the carcass and spleen are slightly heavier but the effects on meat quality are negligible. It is not suggested poor exsanguination is a good thing, but should it occur, it is not the disaster some meat inspectors suppose.