Nineth Week - Respiratory

"At a rate of 70 beats per minute over an average lifetime of 75 years your heart will beat 2,759,400,000 times... you wouldn't think it would make that much difference if it missed just a few..." - Dr Pete Jones, University of Otago.

I'm back from mid-semester one break and feeling pumped, ready to go! 

Whether you believe in creationism, evolutionism or are sitting-on-the-fence-ism, you should agree that the human body is amazing. Sure, there may be a few personalities, political or sociocultural identities that grind your gears, but you must admit that at a body systems level the functioning body is extraordinary. We are all extra-ordinary! Have you ever considered the complexity and thus beauty of the working body? In a healthy body, there are multiple systems working in harmony: respiratory, cardiovascular, endocrine, musculoskeletal, immune and neural. Nearly everything, at the cellular and microscopic level is moving or being moved in a coordinated fashion. It is this movement that we recognise as life. Movement is what makes the world go around!! ... And we were all built to move, so lets move!!

Physical activity is fantastic. At moderate levels it has been shown to reduce the risk of depression, improve self-esteem, minimise the risk of cardiovascular disease, maintain functional activities of daily living, decrease the risk of some cancers, offset the effects of ageing and smoking tobacco. Smoking is an unhealthy habit, and unlike the other conditions listed above, it is a lifestyle decision people find themselves becoming dependent on. Smoking is so unhealthy, that even if you were to be physically active, you would still be at a substantially high risk for all the conditions mentioned above! As health professionals, we must pass a smoking cessation course - this was the highlight of Monday's 8am class. Helping smokers to live healthier lives is as much about lifestyle modification and smoking cessation as it is 'being physically active' alone. There is much to discuss about smoking (like, how it only takes ~6-9 seconds for nicotine to reach the brain, via the respiratory system!); but I would like to end this paragraph emphasising the benefits of a smoke-free lifestyle: reducing the risks of all cause morbidity, improved quality of life, financially better off, not harming those in your immediate surroundings with smoke and smelling better too.

Coincidently, we had our respiratory lab on Tuesday. This involved analysing O2 and CO2 under different conditions - I'll explain. We measured alveolar ventilation using a Haldane-Priestley tube. I searched Google for an image of this device, but found none that resembled what we used in our lab. Basically, it is a clear, plastic tube with a mouth piece and a valve near the mouth piece. A syringe is placed in the valve to suck out expired air. You can actually see part of it being held on the right hand side of the image. We tested the gases after both hypo- and hyperventilation... there were chocolates at stake for the highest measured CO2 in the breath-holding (hypoventilation) task and highest measured O2 in the forced hyperventilation tasks. This made quite a few of us light headed! The lab became even more amusing when we had 'breathing and gym' themed music (e.g. Take My Breath Away, performed by Berlin) playing whilst were were using the Douglas-bags. The Douglas-bag caught all of the air that I expired (breathed out). We compared the ratio of the bulk flow (of air) from rest and after exercise - this [respiratory exchange ratio] relates to the energy substrate (carbohydrate, fat or protein) that is primarily being used. But the main point of the lab was to look at the haemoglobin (Hb) dissociation curve: Hb saturation of a gas plotted against the partial pressure of a gas, namely O2 and CO2. ...All you need to know is that it was a good lab experience.

One PHTY254 lab this week included gait. For a second I thought we were back at primary school because we got to put ink on our feet and stride along a sheet of paper, leaving behind our foot prints!! ...The fun ended when we had to measure distances and angles of the foot, feet and stride patterns. On the subject of primary school... I find it ironic how many concepts use the acronym ABC. It is as if they wish to undermine the complexity of the process by stating it is as simple as learning your 'ABCs' - it's not that simplistic (if it were, we'd all be health professionals). On a positive note, it does have its merits - if you were to have a guess of an acronym that is used to explain something, a good bet would be the ABCs. First aid has its ABCs - Airway, Breathing, Circulation. Neuro has a activity-specific balance confidence scale. Cognitive behaviour therapy's ABCs are Antecedents, Beliefs, Consequences. Athletics trainers use Agility, Balance, Coordination. Smoking cessation practitioners Ask, Briefly explain benefits and offer Cessation support. ABCs for life!!

My subjects at a glance: Anatomy is now focusing on soft and hard tissues/structures associated with the vertebral column. Physiology has just finished covering the cardiovascular system (our cardio lab is in a fortnight). Rehabilitation science is focusing on clinical gait analysis. Clinical Practice was all about passing our smoking cessation 'quit card provider' course - we can now offer discounts on nicotine replacement therapy products, like gum, lozenges and patches.

The human body is amazing - so lets look after it!