Respiratory Medicine

Of Mice And Men Inoculating Mice With Viruses

In an experiment involving the ever-unfortunate mice, the following steps occurred:

  • Mice inoculated with influenza virus
  • Th17 cells activated and migrate to respiratory and gastrointestinal systems
    • Both respiratory and gastrointestinal tracts have mucosa, so they are similar in a way
  • Th17 cells produce cytokines IL-17A and IFN-γ
    • These cytokines mess with intestinal bacteria
    • Results in less Lacto-, more Entero-
  • Intestinal injury

References

  1. Racaniello, V. (2014). How influenza virus infection might lead to gastrointestinal symptoms. [online] virology blog. Available at: http://www.virology.ws/2014/12/10/how-influenza-virus-infection-might-lead-to-gastrointestinal-symptoms/ [Accessed 5 Feb. 2020].
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Management Of COPD

It’s always the greatest when mnemonics match the thing they’re relating to.

Even if it does involve a couple of extra Ps.

COPPPPD

Inhaled Corticosteroids if FEV1>50% with 2+ exacerbations/year and a short course of systemic corticosteroids for severe exacerbations

Home Oxygen and oxygen during exacerbations to maintain SpO2 at 88-92%

Prevention with smoking cessation and immunisations against influenza and pneumococcus

Physical activity

Pulmonary rehabilitation

Penicillin, meaning amoxycillin or the non-penicillin doxycycline for severe exacerbations

Inhaled bronchoDilators

References

  1. Chronic obstructive pulmonary disease. In: eTG complete [Internet]. Melbourne: Therapeutic Guidelines Limited (eTG July 2018 edition); 2015 Mar.

Light’s Criteria For Pleural Effusions

If any of the following conditions are met, it is an exudate, full of protein and turbid, unclear fluid. Think malignancy or certain infections.

Light’s Criteria

  1. Pleural fluid protein / serum protein > 0.5
  2. Pleural fluid LDH / serum LDH > 0.6
  3. Pleural fluid LDH > 2/3 x upper limit of normal serum LDH

Memory Aid

  • Pleural
    • Criterion 1 = protein
    • Criterion 2 = LDH
    • Criterion 3 = LDH again
  • Increasing numbers
    • 0.5
    • 0.6
    • 0.666666 to infinity

References

  1. MDCalc. (2018). Light’s Criteria for Exudative Effusions. [online] Available at: https://www.mdcalc.com/lights-criteria-exudative-effusions [Accessed 14 Sep. 2018].
  2. Exeter Clinical Laboratory International. (2018). Transudate or Exudate / Blood Sciences Test. [online] Available at: https://www.exeterlaboratory.com/test/transudate-or-exudate/ [Accessed 14 Sep. 2018].

Caffeine In Asthma

Caffeine is similar to theophylline, which can be used to treat asthma through bronchodilation from smooth muscle relaxation and a reduction in airway responsiveness.

A Cochrane review found that caffeine improves lung function in people with asthma, up to 4 hours.

References

  1. Welsh EJ, Bara A, Barley E, Cates CJ. Caffeine for asthma. Cochrane Database of Systematic Reviews 2010, Issue 1. Art. No.: CD001112. DOI: 10.1002/14651858.CD001112.pub2
  2. DrugBank. (2005). Theophylline. [online] Available at: https://www.drugbank.ca/drugs/DB00277 [Accessed 5 Apr. 2018].

Podcast 018: Respiratory Medicine With Dr Lucy Morgan

We all crave love, but first we require oxygen. Lungs are such needy things!

In this episode, Dr Lucy talks about respiratory medicine, pub rock and marriage.

Podcast

About the guest speaker

Dr Lucy Morgan is a staff specialist physician in respiratory medicine. She maintains links to The University Of Sydney and Concord Repatriation General Hospital, where she works as an Associate Professor.

Music credits

Opening and closing themes by Lily Chen.

Podcast 017: Medical Research With Julia Chapman

Fake medicine is based on hogwash and wizardry, while real medicine is based on evidence and clinical trials.

Without the guidance of data, patient management is in confusion! No one really knows what to do! That makes medical research integral to accurate diagnosis and treatment.

In this episode, Julia talks about life as a medical researcher, how research applies to medical doctors and the challenges that research involves.

Podcast

About the guest speaker

Julia Chapman has worked at the Woolcock Institute since 2008 across a range of industry sponsored and investigator driven sleep and respiratory clinical trials. She recently completed her PhD which focussed on the treatment of daytime sleepiness in OSA with wakefulness promoters modafinil and armodafinil, including the longest randomised controlled trial of either of these drugs in OSA.

Julia left school thinking that she would one day be a professor of languages, but after studying pharmacology at the University of Sydney, she found that science was her passion. For her initial PhD work on the use of modafinil in mild-moderate OSA patients not using other treatments, she was awarded the Australasian Sleep Association’s New Investigator Award in 2013. She was awarded a postdoctoral research fellowship from NeuroSleep under the supervision of A/Prof Nat Marshall and Prof Ron Grunstein, who together are part of a team planning to establish a Sleep Clinical Research Network in Sydney and surrounding areas. She is now working on establishing research into the combined effects of shift work and OSA, as well as research in insomnia and chronic fatigue syndrome.

Music credits

Opening and closing themes by Lily Chen.

Croup

Croup is formally titled acute laryngotracheobronchitis, but that’s a less catchy name.

It’s a viral upper respiratory tract infection that affects the larynx and trachea. It primarily occurs in children under 5 years old.

Symptoms

Croup attacks kids, so the acronym for symptoms must be in the appropriate theme.

CHILD

  • Coryzal prodrome
  • Hoarse voice
  • Inspiratory stridor
  • Like a barking seal cough
  • Difficulty breathing

Management

  • Single-dose corticosteroids of any of the following:
    • Dexamethasone orally
    • Prednis(ol)one orally
    • Nebulised budesonide

PLUS

  • Single-dose nebulised adrenaline if severe
    • Repeat after 30 minutes if no improvement
    • Observe for 4 hours after administration
    • ICU review if ineffective

References

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

Dornase Alfa

Dornase alfa is a mucolytic medication used in the treatment of cystic fibrosis. By cutting apart extracellular DNA, it makes mucus thinner.

References

  1. Genentech. (2018). How Pulmozyme works. [online] Available at: http://www.pulmozyme.com/how-pulmozyme-CF-treatment-works [Accessed 20 Jan. 2018].
  2. Yang, C., Chilvers, M., Montgomery, M., & Nolan, S. J. (2016). Dornase alfa for cystic fibrosis. The Cochrane Database of Systematic Reviews, 4, CD001127.

Transudate Versus Exudate

Both are fluids that can occur in the body during inflammation or changes in liquid-solid (oncotic-hydrostatic) pressures.

Memory aids

Transudate is transparent, because it is clear and has a low protein content. It comes from a deranged balance of oncotic-hydrostatic pressures. As a generalisation, think systemic disease.

Exudate involves extruded proteins. It has a comparatively high protein content. As a generalisation, think local inflammation or malignancy.

Pleural effusions

A pleural effusion can involve transudate or exudate. Light’s Criteria is used to determine which is the case.

References

  1. Exeter Clinical Laboratory. Blood Sciences Test / Transudate or Exudate. Retrieved 19 March 2017, from http://www.exeterlaboratory.com/test/transudate-or-exudate/
  2. Life in the Fast Lane Medical Blog. Pleural Fluid Analysis. Retrieved 19 March 2017, from https://lifeinthefastlane.com/investigations/pleural-fluid-analysis/
  3. American Family Physician. (2006). Diagnostic Approach to Pleural Effusion in Adults. Retrieved 19 March 2017, from http://www.aafp.org/afp/2006/0401/p1211.html