Potpourri

Just a quick-hit collection of articles I’ve wanted to highlight/catalogue for future reference, but couldn’t find the time for deep dives into each:

Shared Decision Making in Patients With Suspected Uncomplicated Ureterolithiasis: A Decision Aid Development Study.
For this common clinical scenario in the Emergency Department, the authors have developed a patient-facing packet to facilitate shared decision-making. However, more important than the product, is the process these authors have described for its creation. A similar roadmap could be followed to address similar opportunities in your department.

Reduction of Inappropriate Antibiotic Use and Improved Outcomes by Implementation of an Algorithm-Based Clinical Guideline for Nonpurulent Skin and Soft Tissue Infections.
Amazing – using the correct antibiotics reduces treatment failures and, likewise, treatment failures necessitating admission to the hospital. This is an effort-intensive intervention featuring provider education and individual prescribing feedback, but, given the limitations, can be considered a change management success. Whether this can be replicated at your institution will depend on many cultural factors.

Utility of INR For Prediction of Delayed Intracranial Hemorrhage Among Warfarin Users with Head Injury.
Here’s a topic with a ton of practice variation – do you admit patients with closed head injury on anticoagulation for observation? This retrospective review of those patients just on warfarin tries to make the case patients with INR <2 are safe for discharge, whereas those with higher scores are not. Again, however, the yield of observation is somewhere south of 1% in their entire therapeutic cohort, making it truly challenging to find the inflection point of value. Another opportunity for shared decision-making?

Performance of Novel High-Sensitivity Cardiac Troponin I Assays for 0/1-Hour and 0/2- to 3-Hour Evaluations for Acute Myocardial Infarction: Results From the HIGH-US Study.
A detailed look at high-sensitivity Troponin I rule-in/rule-out algorithms suggests a 0/1-hour strategy is similar to a 0/3-hour strategy. Overall, while the disposition of patients is likely to be more rapid from the 0/1 hour strategy, a greater proportion of patients ultimately fall into the “intermediate” zone requiring further observation and diagnostics. Certainly, combinations of hsTnI and other risk-stratification instruments ought to mean the majority of patients with straightforward chest pain presentations may be discharged from the Emergency Department.

Randomized Clinical Trial of IV Acetaminophen as an Adjunct to IV Hydromorphone for Acute Severe Pain in Emergency Department Patients.
In this trial, patients receiving hydromorphone were randomized to receive adjunctive treatment with IV acetaminophen or placebo. With 159 patients, they found advantages to the multi-modal approach favoring the addition of acetaminophen – but the confidence interval for their primary outcome crossed unity by 0.01. The authors conclude this is a negative trial, but it rather seems to me there’s certainly no harm in adding acetaminophen (it need not be IV) – adding it likely has a favorable effect, even if the effect size may not be large.

Effect of No Prehydration vs Sodium Bicarbonate Prehydration Prior to Contrast-Enhanced Computed Tomography in the Prevention of Postcontrast Acute Kidney Injury in Adults With Chronic Kidney Disease: The Kompas Randomized Clinical Trial.
In news surprising no one, another trial fails to show benefit of prehydration in staving off post-contrast exposure acute kidney injury. As seen on Twitter, rather than “contrast-induced nephropathy”, the clinical paradigm is effectively “contrast-adjacent nephropathy.” The impairment in renal function is associated with the underlying medical illness and not the exposure to IV contrast. Thus, no intervention – such as prehydration – can prevent such.

Coronary CT Angiography in Patients With Non-ST-Segment Elevation Acute Coronary Syndrome.
This interesting observational study evaluated patients with a diagnosis of non-ST elevation acute coronary syndrome using coronary CT angiography prior to invasive coronary angiography. The good news: CT angiography was probably useful at excluding obstructive coronary disease. The bad news: nearly 70% of patients had a coronary stenosis identified on invasive angiography, so patient selection prior to CT angiography will be important to improve the value of using it as a screen to prevent invasive angiography.

Industry Payment to Vascular Neurologists: A 6-Year Analysis of the Open Payments Program From 2013 Through 2018.
As we watch our healthcare delivery system struggle and groan under the various strains and burdens, one of the culprits has always been the influence of pharmaceutical/device manufacturers targeting investments to improve uptake of their products. In this observational analysis of the OpenPayments database, these authors identified the recipients of financial support from the manufacturers of endovascular devices. About 16% of vascular neurologists received funding from industry, but over 75% could be identified as “influencers” – chiefs of staff, department chairs, or similar. Pharma et al should always be remembered they are serving the interests of owners and shareholders, and not patients and our healthcare system.

Stayin’ Alive Below 65

Just a quick note looking at this lovely trial hypotension trial, evaluating potential use of lower mean arterial pressure targets in elderly patients receiving vasopressors.

Quick summary: Less is more. With a primary outcome of 90-day mortality, outcomes were no worse in patients randomized to a MAP target of 60-65 mmHg rather than “usual care” (≥65 mmHg) – 41.0% vs. 43.8% (-2.85%, 95%CI -6.75 to 1.05). Stated in formal terms, however, the trial failed to demonstrate a statistically significant difference between the treatment arms, and the confidence interval crosses unity. That said, I certainly agree with the accompanying editorial – it should be considered likely there is a potential advantage to “permitting” hypotension, rather than being hedging against intermittent dips. This trial wouldn’t go so far as to say the 65 mmHg is not the MAP target – patients in the “permissive” cohort still had a mean MAP on vasopressors of 66.7 mmHg, while those in the usual care arm trended higher at 72.6 mmHg – but, additional work looking at lower targets is reasonable.

There are, of course, minor oddities to be observed when considering how (or if) to generalize these data. While 78% of patients received norepinephrine, the second-most popular vasopressor was metaraminol, a predominately alpha agonist, used in almost a third of those randomized. Interestingly, fewer than half the patients enrolled were in “septic shock” by Sepsis-3 definitions, while only another quarter were noted to have “sepsis (not in shock)”. Finally, while the findings are generally consistent across all age cohorts, the mean age is ~75, and nearly 75% of those screened were excluded for one of many reasons.

This study is a lovely demonstration of a rather straightforward underlying principle – MAP is not a measure of tissue perfusion, and is used rather as a surrogate for the ultimately-important microvascular circulation. Making big tubes run at a higher pressure at the expense of clamping down little tubes may be harmful – hence the rationale for this trial, and future ones.

As another random aside, I might make a note here for aspiring researchers – the guidelines will frequently tell you where knowledge gaps exist. The 2012 Surviving Sepsis guidelines gave the MAP >65 target a “1C” recommendation, with “1” meaning consensus for the recommendation was strong, but “C” meaning the evidence was weak. Looking at guideline recommendations and their accompanying level of evidence provides: 1) clues as to which clinical questions are important enough to be addressed by guidelines, and 2) the gaps in the evidence. Guideline authors will even, frequently, explicitly call out certain clinical questions for further study. I wouldn’t go so far as to call it a roadmap to clarifying the important questions in your specialty, but it certainly could be fertile.

“Effect of Reduced Exposure to Vasopressors on 90-Day Mortality in Older Critically Ill Patients With Vasodilatory Hypotension”
https://jamanetwork.com/journals/jama/fullarticle/2761427