Treatment Options For Hyperkalaemia

If hyperkalaemia is indeed real and not caused by haemolysis or a bad sample, treatment can be appropriate. It’s urgent if there are ECG changes.

  • Calcium gluconate
    • Stops membrane depolarisation
    • Does not reduce the serum potassium level
  • Sodium bicarbonate IV
    • To treat metabolic acidosis, which can be a potential underlying cause
      • Potassium moves out of cells because it exchanges with hydrogen ions
  • Insulin and glucose IV
    • Use short-acting insulin
    • To promote uptake of potassium into cells
    • Effective in kidney failure
  • Polystyrene resin orally
    • Removes potassium from bowel lumen by exchanging it for sodium or calcium
    • Comes in sodium or calcium varieties, called Resonium
      • Sodium type adds to sodium load in body
      • Calcium type avoids this but is unsuitable in hypercalcaemia
  • Dialysis
    • Last resort if extreme hyperkalaemia and nothing else works

Of course, the underlying cause should be treated; if it’s hypoaldosteronism, such as from adrenal insufficiency, corticosteroids should be given. If it’s volume depletion, that should be corrected. If the hyperkalaemia is caused by a medication, that medication should be ceased.

References

  1. Electrolyte abnormalities. In: eTG complete [Internet]. Melbourne: Therapeutic Guidelines Limited (eTG November 2017 edition); 2017 Nov.
  2. acutecaretesting.org. (2013). On the relationship between potassium and acid-base balance. [online] Available at: https://acutecaretesting.org/en/journal-scans/on-the-relationship-between-potassium-and-acid-base-balance [Accessed 17 Feb. 2018].
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Podcast 014: Junior Doctor With Dr James Ooi

Going from medical student to doctor means a life full of money and responsible employment. However, is it the start of a new life as a societal contributor or the death of freedom and time?

As a child, your biggest aspiration might have been to become an astronaut. As a medical student, your biggest aspiration might be to become a doctor. As a doctor, your biggest aspiration might be to take early retirement and never work again. That’s how one horror story might go.

But what is it really like being a medical intern or resident? Is being a junior doctor akin to administrative slavery or is it a chance to be more involved in patient management and help the world?

In this episode, Dr James talks about junior doctor life, coffee, spontaneous patient bleeding and what keeps him sane.

Podcast

About the guest speaker

Dr James JY Ooi is a PGY2 resident doctor at The Alfred Hospital, Melbourne. After graduating with honours from Monash University in 2016, Dr Ooi tinkered as a novice researcher, authoring publications in the obviously related fields of Rheumatology and Urology. It is a driving passion for improved quality-of-life and functional outcomes that colours Dr Ooi’s work. To that effect, he optimistically jogs towards a career in Sports and Exercise Medicine.

Outside of medicine, James enjoys being suitably average at any sports and pretending to be intellectual, sipping coffee whilst consuming Sir David Attenborough’s latest. Should anyone have the misfortune of meeting this boy man, he recommends forwarding all complaints to his beloved fiancée Michelle, who has carried him through more tough times than can be counted.

Music credits

Opening and closing themes by Phil Poronnik.

Contraindications To Lumbar Puncture

A lumbar puncture is a procedure that involving drawing out cerebrospinal fluid, fondly known as CSF. For example, it can be used to check CSF for immune cells and glucose levels in suspected meningitis.

Lumbar puncture is considered an invasive procedure. But even with that aside, it’s not appropriate for everyone. That is, it does not suit all patients.

Contraindications to lumbar puncture are:

  • Skin infection at the lumbar puncture site
  • Uncorrected coagulopathy
  • Increased intracranial pressure
  • Trauma to the spinal cord

References

  1. Queen’s University School of Medicine. (n.d.). Contraindications. [online] Available at: https://meds.queensu.ca/central/assets/modules/lumbar_puncture/contraindications.html [Accessed 2 Feb. 2018].

Schober Test

Purpose

The Schober test checks the lumbar flexion range of motion.

Suppose the spine is straight. If it bends forward, like in lumbar flexion, the posterior surface of the back should stretch out to accommodate the movement.

For example, if you have a circle drawn with a thick line, the circumference of the outer side of the line is greater than the circumference of the inner side of the line.

If the posterior back doesn’t stretch out all that much, it means the range of lumbar flexion is limited.

Steps

  • Patient has back facing you
  • Find the level of the posterior superior iliac spine
    • PSIS is roughly at L5-S1 level
  • Make a mark 10cm above that and another mark 5cm below it
    • Memory aid: the higher number is higher up
    • The distance between the points is 15cm
  • Tell patient to touch toes
    • Patient bends over, which is lumbar flexion
  • If the distance between the points is <20cm, there is limited lumbar flexion
    • Alternatively, means the increase in distance from the lumbar flexion movement is <5cm

References

  1. Physiopedia. (n.d.). Schober test. [online] Available at: https://www.physio-pedia.com/Schober_test [Accessed 2 Feb. 2018].
  2. General Practice Notebook. (n.d.). Schober’s test. [online] Available at: https://www.gpnotebook.co.uk/simplepage.cfm?ID=1422917656 [Accessed 2 Feb. 2018].

Treatment With Glucose And Insulin In Diabetic Ketoacidosis

Diabetes mellitus is a disease of not enough insulin. It’s a story of pancreatic insufficiency when it comes to insulin.

In Type 1, there’s no insulin produced. This is an absolute insulin deficiency.

In Type 2, the gradually failing pancreas doesn’t produce enough insulin to meet the body’s increased requirements; in certain people, the body is a needy thing that becomes less and less sensitive to insulin over time, so more is needed of it. This is a relative insulin deficiency.

If diabetic ketoacidosis is a crisis characterised by a lack of insulin, why is it that both intravenous glucose and insulin are part of the treatment?

This is because DKA has two big issues:

  1. Acidic blood pH because of too many ketones
  2. Hyperglycaemia

Treatment with insulin corrects both of these. However, the hyperglycaemia resolves first. IV glucose gives more time to allow the insulin to keep suppressing ketones, thus addressing the acidosis as well.

References

  1. Diabetic ketoacidosis. In: eTG complete [Internet]. Melbourne: Therapeutic Guidelines Limited (eTG November 2017 edition); 2017 Nov.

Thomas Test

Purpose

The Thomas test looks for hip pathology, namely of issues with hip flexor tightness. This is called a fixed flexion deformity.

For example, there could be a problem with the iliopsoas muscle.

Steps

  • Patient is supine on bed
  • Tell patient to bring knees to chest
    • Patient flexes both knees and hips
    • But not excessively so, otherwise it could give a false positive result
  • Lower one leg straight onto the bed
    • If the thigh is on the bed, it is a normal result
    • If the thigh is off the bed, the patient has a fixed flexion deformity of that side

References

  1. Patel, M. (2011). Thomas test. [online] OrthopaedicsOne. Available at: https://www.orthopaedicsone.com/display/Main/Thomas+test [Accessed 31 Jan. 2018].
  2. Physical Therapy Haven. (2018). Thomas Test. [online] Available at: http://www.pthaven.com/page/show/157779-thomas-test [Accessed 31 Jan. 2018].
  3. General Practice Notebook. (n.d.). Thomas’ test. [online] Available at: https://www.gpnotebook.co.uk/simplepage.cfm?ID=120913935 [Accessed 31 Jan. 2018].

The Point Of Stretching

Muscles are a grand amalgamation of thin actin, thick myosin, calcium ions binding to troponin, tropomyosin and Z-lines. They require ATP to be relaxed and use ATP when they undergo contraction.

Stretching helps realign and lengthen muscles to prevent them from being tight and easily injured.

How are muscle contractions triggered in the first place?

Motor neurons use the neurotransmitter acetylcholine to send messages to muscles, prodding them into action. This causes the in-flow of sodium ions, propagating the action potential onward through the muscles. In turn, this invokes the release of calcium ions inside the cells.

The calcium binds to troponin and the obstructive bits move out of the way, allowing actin and myosin to meet for a sweet, brief moment. This is cross-bridge cycling

References

  1. Biology Stack Exchange. (2015). How is ATP involved in muscle contraction?. [online] Available at: https://biology.stackexchange.com/questions/31323/how-is-atp-involved-in-muscle-contraction [Accessed 26 Jan. 2018].
  2. Anon, (n.d.). Muscle Fiber Contraction and Relaxation. [online] Available at: http://oerpub.github.io/epubjs-demo-book/content/m46447.xhtml#fig-ch10_03_01 [Accessed 26 Jan. 2018].
  3. The MIT Tae Kwon Do Club. (2008). STRETCHING AND FLEXIBILITY – Physiology of Stretching. [online] Available at: http://web.mit.edu/tkd/stretch/stretching_2.html#SEC13 [Accessed 26 Jan. 2018].
  4. Harvard Health Publishing. (2013). The importance of stretching. [online] Available at: https://www.health.harvard.edu/staying-healthy/the-importance-of-stretching [Accessed 26 Jan. 2018].