BT_PO 1.77 Outline the significance of oncotic pressure, colloid osmotic pressure and reflection coefficients

This is not a particularly exciting topic in my books (no-one else has been inspired by it either given than it is still in the list of unposted LOs).

Our bodies would be a bit of a disaster if no oncotic pressure could be generated.

I actually was asked about this topic in my primary exam back in 1999!!

The detail here is all at a level you should know. I have used Hemmings and Egan Pharmacology and Physiology for Anaesthesia 2e Ch 24 (it’s lovely and new) as the resource here

BT_PO 1.77 Outline the significance of oncotic pressure, colloid osmotic pressure and reflection coefficients

Oncotic pressure is presented by 𝛱 in the Starling equation T/F

Oncotic pressure in the capillaries is higher at the venous end compared with the arterial end T/F

Interstitial oncotic pressure encourages fluid to move out of vessels T/F

Albumin is the major determinant of plasma oncotic pressureT/F

The glycocaylx is now thought to be a major contributor to vascular permeability T/F

The glycocaylx is strongly positively charged, which binds and holds in negatively charged albumin T/F

BT_PO 1.89 Outline the role of prostaglandins and other autocoids

T/F  an autocoid is a biological substance which acts like a local hormone, has a brief duration, and acts near the site of synthesis

T/F  examples of autocoids include: prostaglandins, histamine, serotonin, nitric oxide, and endothelins

T/F  all prostaglandins are derived from arachidonic acid (a fatty acid present in the phospholipids of cell membranes), and contain 20 carbon atoms, including a 5 carbon ring

T/F  cyclo-oxygenase 1 (COX 1) is expressed constitutively in most cells, and is responsible for the production of prostaglandins involved with homeostatic functions

T/F  prostacyclin (PGI2) is a vasodilator, and inhibits platelets

T/F  PGE2 plays a role in preventing gastric ulcertation, by increasing gastric mucus production and inhibiting gastric acid secretion

T/F  many drugs work by either inhibiting the synthesis of various prostaglandins, or mimicking their action

Fun Trivia
Why are prostaglandins called “prostaglandins”? What’s the significance behind the name?

BT_PO 1.82a Outline basic cellular physiology in particular The structure of the cell membrane and trans- membrane transport mechanisms The composition and regulation of intracellular fluid The generation of the trans-membrane potential Energy production by metabolic processes in cells

AKA read most of Ganong Chapters 1 and 2

The intracellular compartment contains about 5% of body water     T/F

Colligative properties are dependent upon the types of particles in a solution    T/F

The sodium/potassium pump prevents cellular oedema AND contributes to the membrane potential     T/F

Oxidative phosphorylation occurs in red blood cells     T/F

In some cells glucose crosses the cell membrane by secondary active transport     T/F

Bonus question (the answer can be worked out from material in chapter one) – the pH electrode has a semi-permeable membrane with the selective diffusion of hydrogen ions creating an electrical gradient which is measured. What equation is used to calculate the concentration of hydrogen ions from the electrical gradient?

And remember it’s the webinar today!

BT_RT 1.4 Discuss oxygen delivery and outline indicators of tissue oxygenation in resuscitation

Amazing sunrise this morning!

I though that this topic fit comfortably with yesterday’s post on the consequences of anaemia.

Oxygen delivery is an important issue for us. Knowing what happens as tissue oxygenation becomes impaired, will help you to understand the basis of the indicators we use.

Nunn’s Respiratory Physiology has a comprehensive chapter on Oxygen, Oh’s Manual of Intensive Care chapter on Oxygen Therapy (Ch 28) contains good information on measures of tissue oxygenation at the start of the chapter and here is an article from BJA Education (I think the CPT section is beyond the scope of the primary exam )

BT_RT 1.4 Describe oxygen delivery and outline the use of indicators of tissue oxygenation (base deficit, lactate, mixed venous oxygen saturation) in resuscitation

All the statements below are fairly core

In health, at rest, less than 30% of oxygen delivered to the tissues is used T/F

All organs have the capacity to increase their oxygen extraction ratio if oxygen supply is decreased T/F

Mixed venous blood can be sampled from a central line T/F

Lactate is only produced under anaerobic conditions  T/F

Base excess is positive with lactic acidosis T/F



BT_GS 1.2 Explain receptor activity with regard to: Ionic fluxes, Second messengers and G proteins, Nucleic acid synthesis, Evidence for the presence of receptors, Regulation of receptor number and activity

Signal transduction refers to the process by which receptors act to mediate their physiologic action  T/F

Important second messengers include cAMP, cGMP , Ca2+ and ITP        T/F

GPCRs have seven membrane-spanning alpha helices       T/F

Some receptors are intracellular             T/F

Receptors can be down-regulated by endocytosis and degradation by lysosymes     T/F