Good morning and welcome to your Wednesday dose of Your Daily Meds.
Bonus Review: What are the functions of the CSF?
Answer: Couple of roles -
Protective role - water bath effect
The CSF is contained in the meninges - acts as a cushion to protect brain from injury
The water bath effect gives a 1400g brain an effective mass of 50g
Buffers rises in ICP
CSF translocation to the extra cranial subarachnoid space
An acute space occupying lesion won’t cause a large rise in ICP until this buffer is exhausted
Remember, CSF is incompressible but mobile
Return of interstitial protein to the circulation
Brain has no lymph vessels
Interstitial protein is absorbed with CSF across the arachnoid villi
Other functions
Probably returns some waste from brain ECF to the circulation
May have a nutritive role (although is low glucose)
Some suggestion that neuropeptides may be transported between brain regions via CSF
Quick Question:
Which of the following is a contraindication to induction of labour?
Prolonged pregnancy
Preeclampsia
Prelabour rupture of the membranes
Gestational diabetes mellitus
Placenta praevia
Have a think.
Scroll for the chat.
Case:
An 80-year-old male comes to the Emergency Department.
The problem: shortness of breath.
He has a history of atrial fibrillation and has a permanent pacemaker in situ.
On examination, he is afebrile and hypertensive to a systolic blood pressure of 200. He has a raised JVP and mild ankle swelling.
A postero-anterior chest x-ray is taken and is shown below:
Which of the following is least likely to be included in the emergency management of this man?
Supplemental oxygen
Intravenous frusemide
Intravenous nitrates
Continuous positive airway pressure (CPAP)
Oral high-dose metoprolol
Have a think.
More scroll for more chat.
No Go:
Induction of labour takes place in approximately 25% of pregnancies. The indications for induction of labour are any circumstances or conditions in which there is a likely benefit from delivery prior to spontaneous labour. These may include:
Prolonged pregnancy
Hypertensive disorders (such as preeclampsia)
Diabetes mellitus
Other systemic medical conditions
Likely or suspected placental insufficiency
Prelabour rupture of the membranes
Multiple pregnancy
Antepartum haemorrhage
Psychological or mental health conditions
Social circumstances
So placenta praevia is a contraindication to the induction of labour as it is a contraindication to vaginal birth. Placenta praevia describes an abnormal placentation near or covering the internal cervical os. It classically presents as painless, vaginal bleeding in the third trimester.
A Wee Bit Wet:
Key to answering this question is recognising the radiological signs of acute interstitial oedema in the setting of heart failure. The chest x-ray shows an enlarged heart with marked prominence of the interstitial markings. The prominent interstitial markings are called Kerley lines and represent expansion of the interstitial space by fluid.
Beta-blocker initiation, such as metoprolol, is not recommended in the acute, decompensated phase of heart failure.
It is used in the management of heart failure with reduced ejection fraction and is initiated slowly.
If this man had already been taking a beta-blocker when he had presented with shortness of breath, there would likely be no benefit in ceasing it. The risk comes from initiating beta-blocker therapy while decompensated. The other options in this question all form the mainstay of acute decompensated heart failure management. Nitrates are especially useful when there is high systolic blood pressure.
Bonus: How is CSF different from Plasma?
Answer in tomorrow’s dose.
Closing:
Thank you for taking your Meds and we will see you tomorrow for your MANE dose. As always, please contact us with any questions, concerns, tips or suggestions. Have a great day!
Luke.
Remember, you are free to rip these questions and answers and use them for your own flashcards, study and question banks.
Just credit us where credit is due.
Your Daily Meds - 1 December, 2021