hypoxia

Question 1

whats co and co2 binded to hB?

Answer 1

carboxy hemaglobin - co

carbaminohb- co2

Question 2

What can cause hypoxaemia

Answer 2

Less oxygen in the air

hypoventilation (taking less 02 in and increase in co2)

disturbances in the diffusion of oxygen across the alveoli e.g pulmnondary edema or if the alveolar capillary membrane has been destroyed

capillary membrane less perfusion to the alveoli v/q mismatch

a decrease in HB due to anemia can cause hypoxemia

Question 3

is cyanois always related to hypoxemia

Answer 3

NO. it is possible to be hypoxemic with no cyanois present because you have to reach a certain threshold of a lack of 02 binding to Hb to be called cyanotic

for example in hypochromic anemia , the perosn will ntot be cyanotic and also in cynanide poision because remember the bindin sites of Hb are still occupied just with co

Question 4

Give an example of a right-to-left shunt

Answer 4

in the the case of a decrease in the ventilation perfusion ratio so therefore a decrease in ventilation which results in blood from the right side of the heart going to the left side of the heart deoxygenated

Question 5

RESPIRATORY DISTRESS SYNDROME OF THE NEWBORN

Answer 5

hyaline membrane disease, can be attributed to an immature pulmonary system and decreased surfactant. It is a condition of pulmonary hypoxia and injury result- ing from widespread primary atelectasis

With alveolar collapse, ventilation is decreased. Hypoxia develops this causes damage to the lung and hence inflammation wbc comes to the recuse, they release their cytokines causing more damge leading to edema further worsening the problem

Inflammation also results in the pro- duction of hyaline membranes, which are white fibrin accumulations lining the alveoli. Fibrin deposits further decrease gas exchange and reduce lung com- pliance. With a decrease in lung compliance, the work of breathing is increased.

pulmonary arteriolar vasoconstriction. Pulmonary vasoconstriction can lead to an increase in right-heart volume and pressure, resulting in a shunting of blood from the right atrium through the still-patent foramen ovale of the newborn, and directly to the left atrium. Likewise, high pulmonary resistance can result in deoxygenated blood bypassing the lungs and being delivered directly to the left side of the body via the ductus arteriosus.

At first the infant demonstrates rapid, shallow breathing in an attempt to meet this high oxygen demand, causing initial blood gases to indicate respira- tory alkalosis as carbon dioxide is blown off. However, the infant soon tires

from the extraordinarily difficult alveolar and lung expansion and is unable to keep up the respiratory effort. When this occurs, respiratory effort slows and blood gases reflect respiratory acidosis (buildup of carbon dioxide) and the onset of respiratory failure.

Question 6

isk Factors for Respiratory Distress Syndrome

Answer 6

The primary risk factor for the development of RDS of the newborn is pre- maturity. because the surfact cells do nor delevop till a certain time period so therfore there is a HIGH SURFACE TENSIOS

also what makes it worse is babys aleveoli are small so it takes even higher amount to overcome the surface tension

chest wall muscles arent devloped so effort to expland the chest

also seems to be a link between insulin dependant mothers and rds

Question 7

how can we divide hypoxic hypoxia

Answer 7

exogenous - TO GET INSIDE THE BODY

endogenous - TO GET IN TO THE BLOOD