Cyanosis Blue Skin on patient during a physical examination.

Blue-red Skin or Cyanosis During Patient Physical Examination

This is most plain on the parts that normally are bright red, hence more than elsewhere on the mucous membranes, on the lips, cheeks, etc. ; also on the knees, the phalanges of the fingers, and under the finger-nails (nail beds).  A moderate degree of cyanosis, therefore, would only be discovered at these parts.  A marked degree, on the other hand, exhibits a blue color spread over the whole body, while those parts, especially the mucous membrane, become black-blue.

The cyanosis of the newborn, with heart-failure, is so striking to the experienced observer, that it is regarded by him as pathognomonic.  One only sees anything like it in the death agony, and, exceptionally, in severe spasms with marked interference with breathing.  The combination of cyanosis with great paleness is designated as " livid skin."

Cyanosis arises from the blue-red color of the capillaries, and this, as is well known, is caused by an accumulation of carbonic acid and deficiency of oxygen and that is to say, by the venous or hypervenous character of the capillary contents.

Carbonic acid in the blood (serum and red corpuscles) arises from :

1. Interference with the exchange of gases in the lungs. 

2.  From the slowing of the capillary circulation and the consequently dimin ished gas-exchange in the tissues, that is to say, the diminished giving up of CO2 by the tissues to the blood.

Cyanosis arises, therefore : 1.  In disturbed respiration and circulation through the lungs ;

2.  In disturbance of the "greater circulation," which may be general or circumscribed according as the stoppage maj be general or local.  The two causes may be combined. 

Here belong to 1 :

(a) All conditions which cause a narrowing of the larger air passages or of a large number of small bronchi : inflammation of the neighborhood of the pharynx or entrance to the larynx ; retro pharyngeal abscess, angina Ludovici; very exceptionally a diphtheria of the throat.  (In all of these cases the interference with respiration is either direct or dependent on oedema of the glottis.) The following are enumerated : spasm of the glottis, paralysis of the dilator of the glottis (crico-arytenoideus post.), all acute and chronic inflammations of the larynx, but especially croup ; tumors of the larynx ; cicatricial narrowing of the larynx ; foreign bodies in the larynx (something swallowed or vomited) ; also foreign bodies, croup and scars in the trachea or one or both primary bronchi, compression of these from without by enlarged glands, aneurism of the aorta, etc. ; mediastinal tumors, etc. ; bronchial spasm ; and severe difi"use bronchitis, espe cially the acute croupous form.

{h) All diseases of the lungs and diseases in the neighborhood of the lungs which hinder their expansion or ivholly compress them: emphysema of the lungs ; all forms of consolidation ; pleuritic and great pericardial exudation, pneumothorax ; tumors in the chest cavity ; abdominal diseases with marked upward pressure of the diaphragm.

(c) Paralysis of the respiratory muscles : bulbar paralysis, peripheral neuritis ; paralysis of diaphragm from peritonitis ; spasm of the

A very distressing case of suffocation from the lodgement of a large piece of meat in the pharynx, and the consequent closure of the entrance of the larynx, presented itself at the Leipzig medical clinic.

Muscles of respiration, epilepsy, tetanus, but, on the other hand, very rarely hystero-epilepsy ; special muscular diseases : myopathic forms of progressive muscular atrophy, trichinosis, myositis ossificans.

Disturbances of the circulation through the lungs occur in a number of the diseases which interfere with respiration.  In emphysema a large number of capillary channels are closed, also in tuberculosis and other chronic lung affections ; a large pleural exudation not only compresses the lungs, but also the capillaries.  This acts in the same way as a hindrance to respiration.

(d) Diseases of the heart which result in obstruction of the pul monary circulation.  It is to be noticed that in the conditions named under (6) a disturbance of the respiration interferes with pulmonary cir culation.  Moreover, we must emphasize the fact that in several of these conditions (especially diseases of the pleura, of the peritoneum, in trichinosis of the diaphragm and intercostal muscles) the insufficient breathing, as well as the cyanosis, will be increased by the pain caused by the act of breathing.  If the physician correctly recognizes the chain of events he will be able to bring relief by the use of narcotics.

In persons very much wasted, especially from tuberculosis, cyanosis may be absent even in spite of the loss of a large part of the breathing surface of the lungs, since the remaining normal portion suffices for supplying the required quantity of oxygen to the diminished quantity of blood.

Under heading 2 :

Slowing of the blood-current in the capillaries of the greater circula tion is dependent upon stopping of the venous outlet.  This can be general and caused by all the conditions of the first category, general cyanosis, or it can be occasioned by a venous stopping of an extremity or of the head, and so produce a local cyanosis.

General venous damming occurs in diminished pumping power of the right ventricle (valvular deficiency, congenital stenosis of the pulmonary artery, diseases of the heart-muscle, large pericardial exu dation with hindenng of the heart's action, considerable emphysema of the lungs with excessive damming of the smaller circulation), and in the rare case of compression of a large venous trunk just before it enters the right auricle (tumors of the mediastinum).

Local venous stasis is caused by closure or marked narrowing of a more or less large venous trunk.  This closure may be produced by compression or by thrombosis of the vein (compression of tbe cava or the extremity of a venous trunk by tumors) ; compression of the cava inferior in connection with the common iliac artery by very large effusion in the peritoneum, or by tumors ; atrophic thrombosis of a vein of the extremity, especially the femoral.  Not infrequently the collateral veins of the skin take up the conveyance of the blood of the venous stasis ; they then become enlarged and sometimes tortuous (see examination of the veins).

For the cyanosis produced by certain poisons, see Examination of the blood.

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