Annalise is in her first trimester of pregnancy, and she has been experiencing severe morning sickness that resulted in hypoproteinaemia and systemic oedema. By reflecting on the BIOL122 learning material and your understanding of the forces responsible for the distribution of water between the intravascular and interstitial compartments, briefly describe how hypoproteinaemia causes systemic oedema. (3 marks)

Hypoproteinaemia refers to abnormally low levels of protein in the blood. This condition can lead to systemic oedema, or swelling, due to an imbalance in the forces that regulate the distribution of water between the intravascular (within blood vessels) and interstitial (between cells) compartments.

1. The distribution of water between these compartments is primarily regulated by two forces: hydrostatic pressure and oncotic pressure. Hydrostatic pressure, generated by the heart's pumping action, pushes water out of the blood vessels. Oncotic pressure, on the other hand, is a form of osmotic pressure exerted by proteins, particularly albumin, in the blood plasma that pulls water into the blood vessels.

2. In a state of hypoproteinaemia, the level of proteins in the blood is reduced. This leads to a decrease in the oncotic pressure. As a result, less water is pulled into the blood vessels from the interstitial space.

3. With the hydrostatic pressure now greater than the oncotic pressure, more water is pushed out of the blood vessels and into the interstitial space, causing swelling or oedema. This is how hypoproteinaemia can lead to systemic oedema.

In Annalise's case, severe morning sickness may have led to nutritional deficiencies, including a lack of protein, causing hypoproteinaemia and subsequently, systemic oedema.

Hypoproteinaemia refers to abnormally low levels of protein in the blood. This condition can lead to systemic oedema, or swelling, due to an imbalance in the forces that regulate the distribution of water between the intravascular (within blood vessels) and interstitial (between cells) compartments.

1. The distribution of water between these compartments is primarily regulated by two forces: hydrostatic pressure and oncotic pressure. Hydrostatic pressure, generated by the heart's pumping action, pushes water out of the blood vessels and into the interstitial space. Oncotic pressure, on the other hand, is a form of osmotic pressure exerted by proteins (mainly albumin) in the blood plasma that tends to pull water back into the blood vessels from the interstitial space.

2. In a state of hypoproteinaemia, the plasma protein level is reduced. This leads to a decrease in the oncotic pressure within the blood vessels.

3. With a lower oncotic pressure, the balance between hydrostatic and oncotic pressure is disrupted. This means that more water is pushed out into the interstitial space than is pulled back in, leading to an accumulation of fluid in the interstitial space, which manifests as systemic oedema.

So, in Annalise's case, her severe morning sickness may have led to nutritional deficiencies, causing hypoproteinaemia and subsequently, systemic oedema.