Fever is an often raised problem in neurocritical care and stroke medicine. Here are some notes from todays lecture.
- Infectious causes
- Drugs (PHE, allopurinol, heparin, minocycline, neuroleptics, serotonergic)
- other central fever forms (in particular in SAH: impending vasospasm), localizing to the hypothalamus, the third ventricle or the pons.
Management. Regardless of your threshold for fever or hyperthermia, you need to work it up systematically.
- History: course of fever, is it still rising, drugs
- Examination: is the body trying to heat or cool (is it fever or hyperthermia?)
- Examination: sources of infection
- Labs: apart from the obvious, think of troponin and procalcitonin (the latter if sepsis is assumed)
Therapy. There are some contexts in which fever or hyperthermia is not to be tolerated: stroke, MI, non-stable tachyarrhythmia. Remember that in the case of sepsis, it is probably better tolerated.
In the case of stroke, we know the following:
- temperature is bad (outcome and mortality-wise)
- it is safe to try to lower temperature (cf. PAIS study)
- it is hard to lower temperature (the Kallmünzer/Kollmar publications)
It is not really clear
- whether it really helps to lower temperature
- what threshold to use
- what methods are efficient
In our Stroke Unit, we decided to introduce a 3 layer approach:
- 37,5°C: low-dose paracetamol or metamizol (4 x 500 mg)
- 38°C: physical cooling and high dose (4 x 1000 of either)
- 38,5°C: combination therapy and forced physical cooling
- 39,5°C: desperate measures
Desperate measures, in particular for central dangerous fever (> 40°C)
- Lytic cocktail (block any neurotransmitter that might be involved in fever generation; since we don’t know which might be, block all of them) using anticholinergically acting neuroleptics + antihistamines + antiserotonergics + pethidine