Opioids Dosing, Methadone and Cross Tolerance

Give the current environment of increased regulation on outpatient non - cancerous drug pain management and OUD, I am listing some very helpful; sites and books and a recent NEJM article on Opioid in Critical Illness.
If you want to become a true opioid expert , learn to dose methadone in the inpatient setting safely and also adjust opioid for cross tolerance when rotating drugs to avoid opioid hyperalgesia this is the book that has it all:


Demystifying Opioid Conversion Calculations- A Guide for Effective dosing by Mary Lynn McPherson . I still have the first edition from 2009 , but the 2nd edition published in 2018 is vastly improved , with multiple patient examples and clinical pearls.


A good website with also an Apple/Android app is https://www.crediblemeds.org/ as it ranks drugs form low to high risk when patient are on methadone and I think we see a lot of them admitted on methadone to the ICU.

Finally, the NEJM article on Opiods in Critical Illness is very helpful, particularly the online appendix with patient examples . I can definitely relate to this and the first example was the multi modal therapy they used on me including nerve blocks  ( it would have been better if the darn epidurals would have stayed  stay in place !!) , and certainly was very grateful for this after my MVA.

Please add comments or pearls of wisdom ....

Suicide Left Ventricle (SLV)

 Dr Fisher saw one of these on her nightshift. Its a well known complication of BAV and TAVR. When a patient develops hours later cardiogenic shock post procedure , this is one of the complications to think off. The link to this case report actually gives a good explanation how the outflow tract obstruction occurs. I have wondered if a preprocedure Brockenbrough sign could predict this complication during initial diagnostic catheterization.

Thanks to Dr Beth Fisher for bringing this case to my attention.

ARDS Phenotyping

ARDS Phenotyping       ( click on link for Lecture)

There isa clinical need to identify biomarkers that are associatedwith treatment response, independent of group membership. Therefore, consensus on biological sampling time points, biological dimension measured, and a standard minimum set of consensus biomarkers is required. The biological sampling should aim to refect the insults to the alveolar capillary membrane (ACM) (exudative phase), deposition of provisional matrix with proliferation of airway progenitor cells (proliferative phase), or interstitial and intra-alveolar fbrosis (fbrotic phase) of ARDS. Tis minimum set of markers could then be used to delineate discriminant markers of ARDS sub-phenotypes that provide prognostic enrichment with either a greater probability of therapeutically valid similarities or a greater likelihood of treatment response.

Cardiovascular clusters in septic shock combining clinical and echocardiographic parameters: a post hoc analysis

The clustering approach combining echocardiographicparameters (LVEF, LVFAC, aortic VTI, RV/LV EDA, ∆SVC, mitral E wave velocity, and E′ wave velocity) and clinical parameters (heart rate, blood pressure, type and dose of catecholamine) allowed us to characterize fve distinct cardiovascular phenotypes, the hemodynamic profles of which correspond to “well-resuscitated” patients (16.9%, cluster 1), patients with LV systolic dysfunction (17.7%, cluster 2), hyperkinetic profle (23.3%, cluster 3), RV failure (22.5%, cluster 4), and sustained hypovolemia (19.4%, cluster 5). Tis approach in clustering without any a priori criteria was able to distinguish diferent phenotypes between all the expected alterations of the macrocirculation.