Blood supply to the head and neck

Question 1

Outline

Answer 1

the blood vessels involved tend to run alongside the nerves of the area, as neuromuscular bundles. they may also enter + leave the bony cavities of the skull through the same foramina + fissures as do the nerves

Question 2

The major arteries

Answer 2

carrying oxygenated blood to head + neck region are the common carotid arteries, which direct branches from the arch of the aorta as it leaves the left ventricle.

Question 3

These travel

Answer 3

up the left + right sides of the neck + are palpable against either side of the larynx as the carotid pulse, often taken by professional resuscitation personnel during medical emergencies.
around this position of palpitation, the common carotids divide into follow major arteries:

Question 4

External carotid artery

Answer 4

supplying all the head outside the cranium, including face + oral cavity

Question 5

Internal carotid artery

Answer 5

supplying all the inner cranial structures, including the brain + the eyes.

Question 6

Once the usual gaseous exchange has occurred

Answer 6

in the capillary beds of the head + neck region, deoxygenated blood tends to flow from the small venules into gradually widening veins, until they reach the main venous vessels of the area

Question 7

External jugular vein

Answer 7

drawing a small area of extracranial tissues only

Question 8

Internal jugular vein

Answer 8

draining the brain + majority of the head + neck tissues

Question 9

These veins

Answer 9

run on + eventually join the superior vena cava + enter the right side of the heart, where deoxygenated blood is pumped to lungs for reoxygenation.

Question 10

The flow of deoxygenated blood

Answer 10

from head + neck region is not always in one direction,, as occurs in other areas of the body. This is because the veins of this area usually do not contain the one-way value system, so blood can flow forwards + backwards depending on changes affecting the local pressure

Question 11

This means

Answer 11

it is easier for localised infections to spread in head + neck regions than elsewhere in body. the blood travels through the most important organ of the body, the brain, + that pathogens may enter the area in a variety of ways:

Question 12

These include

Answer 12

inhaled through nose or mouth
ingested through oral cavity
carried by the circulatory or lymph systems
traumatically deposited through the soft tissues, such as during dental trt, local anaesthetic injection or following head + neck injury