Tag Archives: opioids

Assessing and Interpreting the Critically Ill Patient’s Data and Neurological Assessment

Posted on by
Reply

I am now going to move on, in the Introduction to Critical Care course, to a systems based assessment of the patient where you are expected to compile measurements and observations from the clinical information system, radiologic system and monitors to construct an overview of the patient’s status. This is the crux of intensive care medicine and it is not easy. I am going to visit each system sequentially, and some systems will have multiple tutorials. By the end of this process, you will have compiled all of the data, assessed and processed it, and be ready for the big presentation.

The first tutorial in this part is an overview of patient assessment. It is relatively short but essential.

The Second tutorial in this sequence is on at neurological assessment in the ICU. It contains a discussion about the Glasgow Coma Scale, The Richmond Agitation Sedation Scale and CAM-ICU. I also cover the assessment of suffering (PAID) in critical care.

You will need to assess the patients neurologic status, whether or not they appear to be suffering and what interventions, both environmental and pharmacological, that you are administering to help them.

Ions & The pKa – Local Anesthetics, Opioids and Midazolam

Posted on by
Reply

You may think that this whole ionization and pKa stuff is of little relevance to you as a clinician working in ED, Anesthesiology or ICU, but you are mistaken. The pH of blood (whether or not the [H+] exceeds the [OH-] has major impact on the pharmacokinetics of certain drugs. Moreover, some drugs rely on a differential between extracellular and intracellular pH to be effective.

This tutorial looks at the pharmacology of three types of drugs impacted by pH. These drugs are local anesthetics, opioids and the benzodiazepine – midazolam. All of these agents are weak bases whose degree of ionization varies with pH.

  1. Speed of onset is related to the pKa – the lower the pKa of weak bases the more rapid the onset of action
  2. Duration of action is related to protein binding – particularly albumin (there are other proteins). Albumin depletion is common in critical illness, leading to higher bioavailability and shorter duration of action.
  3. Potency is related to lipid solubility. Fentanyl is highly potent because of this.

This tutorial is supplementary to the acid base course. The material is ESSENTIAL for trainees and practitioners in Anesthesiology and Dentistry. @ccmtutorials http://www.ccmtutorials.org