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My patient with long standing hypertension and obesity with significant weight loss while on a glucagon-like peptide-1 receptor agonist (GLP-1RA), now has a “borderline” blood pressure. Should I consider adjusting his antihypertensive medication(s)?

FA Manian MD, MPH, , , , , , , , , , , , , , , , Leave a comment

Yes, you may very well need to adjust antihypertensive regimen of patients who have experienced significant weight loss while on GLP-1RAs.1,2  

In the STEP-1 trial evaluating the impact of semaglutide on cardiometabolic risk factors in adults who were overweight or obese, 34.3% of the group receiving semaglutide had either reduction in the dose or cessation of antihypertensive medications, compared to 15.6% in the placebo group.2  In SURMOUNT-1 trial examining the impact of tirzepatide on blood pressure reduction, a significant net reduction of 6.8 mm Hg systolic and 4.2 mm Hg diastolic blood pressure compared to placebo over 72 weeks was found; weight loss accounted for ~70% of systolic or diastolic blood pressure reduction. 2

The need to lower the dose of or discontinue antihypertensive medications in the setting of significant weight loss should not come as a surprise since this phenomenon predates the widespread use of GLP-1RA in obesity. 1,3 However, in addition to their impact on blood pressure through weight loss, GLP-1RAs may  lower blood pressure through alternative  mechanisms, including natriuresis, direct vasodilation and reduction in sympathetic nervous system activity.4  It’s also important to remember that GLP-1RAs may reduce both systolic and diastolic blood pressures in patients with hypertension even before significant weight loss is observed! 5

But it’s not just about antihypertensive medications!  The use of GLP-1RAs with its attendant weight loss may also require dosage adjustment or discontinuation of several other commonly prescribed medications (eg, insulin, levothyroxine, and anticonvulsants, phenytoin, warfarin, lithium carbonate, and digoxin).2 So don’t forget to regularly review the medication list of patients who have experienced recent weight loss on GLP-1RAs!

Bonus Pearl:  Did you know that the concept of incretin effect was first proposed in the 1970s based on observations that insulin secretion was 2-3 times higher after oral glucose intake than that after intravenous glucose administration? 5

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References

  1. Manian FA. Antihypertensive medications in patients with weight loss. JAMA Intern Med 2025;185:475. Antihypertensive Medications in Patients With Weight Loss | JAMA Internal Medicine | JAMA Network
  2. Karakus KE, Shah VN, Akturk HK. Tirzepatide-induced rapid weight loss-related thyrotoxicosis. JAMA Intern Med 2024;184:1246-1247. Tirzepatide-Induced Rapid Weight Loss–Related Thyrotoxicosis | Lifestyle Behaviors | JAMA Internal Medicine | JAMA Network
  3. Shantha GPS, Kumar AA, Kahan S, et al. intentional weight loss and dose reductions of antihypertensive medications: a retrospective cohort study. Cardiorenal Med 2013;3:17-25. Intentional weight loss and dose reductions of antihypertensive medications: a retrospective cohort study – PubMed
  4. Lingway I, Mosenzon O, Brown K, et al. Systolic blood pressure reduction with tirzepatide in patients with type 2 diabetes: insights from SURPASS clinical program. Cardiovasc Diabetol 2023;22:66. Systolic blood pressure reduction with tirzepatide in patients with type 2 diabetes: insights from SURPASS clinical program – PubMed
  5. Liu QK. Mechanisms of action and therapeutic applications of GLP-1 and dual GIP/GLP-1 receptor agonists. Front Endocrinol 2024; 15:1431292. Frontiers | Mechanisms of action and therapeutic applications of GLP-1 and dual GIP/GLP-1 receptor agonists

Disclosures/Disclaimers: Reference 1 was written by this contributor. The listed questions and answers are solely the responsibility of the author and do not necessarily represent the official views of Mercy Hospital-St. Louis, Massachusetts General Hospital, Harvard Catalyst, Harvard University, their affiliate academic healthcare centers, or its contributors. Although every effort has been made to provide accurate information, the author is far from being perfect. The reader is urged to verify the content of the material with other sources as deemed appropriate and exercise clinical judgment in the interpretation and application of the information provided herein. No responsibility for an adverse outcome or guarantees for a favorable clinical result is assumed by the author. Thank you!

My patient with long standing hypertension and obesity with significant weight loss while on a glucagon-like peptide-1 receptor agonist (GLP-1RA), now has a “borderline” blood pressure. Should I consider adjusting his antihypertensive medication(s)?

How should I generally go about treating my non-ICU hospitalized patient with newly diagnosed Covid-19 and who doesn’t require more than conventional O2?

FA Manian MD, MPH, , , , , , , , , , , , , , , Leave a comment

Much of the management of Covid-19 hospitalized patients who don’t require ICU care and need no more than conventional 02 (ie, high-flow or mechanical/non-mechanical ventilatory support) depends on the severity of their disease: “mild/moderate” (eg, SpO2≥94% on room air) vs “severe” (eg, Sp02<94% on room air) disease; respiration rate ≥30/min and lung infiltrates on chest radiograph>50% may also be considered, but I personally find these parameters less reliable.  Generally, patients hospitalized with Covid-19-related symptoms (respiratory or otherwise) require specific treatment to keep them from progressing or succumbing to their disease (see Figure below). 1-5

In patients with mild/moderate Covid-19, the first step is to determine whether they are at low risk (ie, NO risk factors) or high risk (ie, ≥1 risk factors) of progression to severe disease.  Recall that there are numerous risk factors for progression, including age (eg, ≥50 y) and many comorbidities, such as diabetes, chronic kidney disease, obesity, smoking (current or former), disability (eg, wheelchair dependence), and mental health disorders (eg, depression), just to name a few.1 If your patient with mild/moderate Covid-19 has ANY Covid-related symptoms and ANY risk factors for progression, you should strongly consider IV remdesivir. If your patient’s admission has nothing to do with Covid-19 but qualify for anti-Covid treatment, an oral anti-viral regimen (eg, nirmatrelvir-ritonavir [Paxlovid]) used for ambulatory patients may also be considered (see related pearl on P4P). If your patient has NO risk factors for progression to severe disease, symptomatic treatment is all that’s needed.

If your patient has severe disease but no need for 02 supplementation, IV remdesivir and prophylactic heparin (either fractionated [eg, enoxaparin] or unfractionated) should be considered; no need for dexamethasone or systemic steroids in this situation.

If your patient has severe Covid-19 and needs supplemental 02, you should consider initiation of remdesivir, dexamethasone and, at the minimum, prophylactic anticoagulation with either a fractionated or unfractionated heparin product as soon as possible.  Use of therapeutic anticoagulation in this setting (ie, outside of ICU) is controversial with NIH guidelines recommending therapeutic heparin for those with elevated D-dimer without increased bleeding risk (CIIa, “weak” with moderate supportive evidence).2,6,7  You may also be able to forgo systemic steroids in your patient with minimal 02 requirement (ie, 1-2 L) per NIH, particularly if immunocompromised, as hypoxia in such patients may be more related to viral infection itself and not significant inflammatory reaction.

If your patient with severe Covid-19 gets progressively worse requiring high-flow oxygen or non-invasive ventilation outside of ICU, you should consider adding baricitinib as a first line immunomodulator (tocilizumab or others in NIH guidelines as an alternative)2 in patients who are not already immunocompromised or do not already have and are not at high risk of secondary infections.

The duration of remdesivir treatment in hospitalized patients is usually 5 days (or until discharge) for severe Covid-19, and 3 days for those with mild/moderate disease. The ultimate duration should be individualized in patients at risk of ongoing viral replication.  One retrospective study in immunocompromised patients hospitalized for Covid-19 found remdesivir to be effective in reducing hospitalization and mortality when initiated within 2 days of hospitalization and given for a median of 5 days, even among those not requiring 02 supplementation or requiring only low flow 02.

Couple more things to keep in mind when managing severe Covid-19. When indicated, remdesivir should be given ideally as early as possible and no later than 10 days after onset of symptoms and dexamethasone should be given for up to 10 days or until discharge.  Anticoagulation, prophylactic or therapeutic, should only be prescribed in the absence of any contraindications for bleeding (see Figure footnote) and continued until discharge for no more than 14 days total.

As with all drugs, please make sure you are thoroughly familiar with the dosing, adverse effects and contraindications to above-referenced medications before prescribing them.

Figure. Management of SARS-CoV-2 positive hospitalized patients requiring no or only conventional 02 due to Covid-19

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References

  1. CDC. Interim Clinical Considerations for COVID-19 Treatment in Outpatients | CDC. Accessed Feb 1, 2024
  2. NIH. Clinical Spectrum | COVID-19 Treatment Guidelines (nih.gov). Accessed Feb 1, 2024
  3. Uptodate. Coived-19 management in hospitalized patients. https://www.uptodate.com/contents/covid-19-management-in-hospitalized-adults. Accessed Feb 5, 2024.
  4. Bash K, Sacha G, Latifi M. Covid-19: A management update. Clev Clin J Med 2023;90:677-683. https://www.ccjm.org/content/90/11/677
  5. Mozaffari E, Chandak A, Gottlieb RL, et al. Remdesivir reduced mortality in immunocompromised patients hospitalized for Covid-19 across variant waves: Findings from routine clinical practice. Clin Infect Dis 2023; 77;1626-34. https://pubmed.ncbi.nlm.nih.gov/37556727/
  6. Merz LE, Fogerty AE. The conundrum of anticoagulation for hospitalized patient with Covid-19. NEJM Evidence 2023;2 (2).  https://evidence.nejm.org/doi/full/10.1056/EVIDe2200329
  7. ATTACC, CTIV-4a, REMAP-CAP Investigators. Therapeutic anticoagulation with heparin in noncritically patients with Covid-19. N Engl J Med 2021; 385:790-802. https://pubmed.ncbi.nlm.nih.gov/34351721/

Disclosures/Disclaimers: The listed questions and answers are solely the responsibility of the author and do not necessarily represent the official views of Mercy Hospital-St. Louis, Massachusetts General Hospital, Harvard Catalyst, Harvard University, their affiliate academic healthcare centers, or its contributors. Although every effort has been made to provide accurate information, the author is far from being perfect. The reader is urged to verify the content of the material with other sources as deemed appropriate and exercise clinical judgment in the interpretation and application of the information provided herein. No responsibility for an adverse outcome or guarantees for a favorable clinical result is assumed by the author. Thank you!

How should I generally go about treating my non-ICU hospitalized patient with newly diagnosed Covid-19 and who doesn’t require more than conventional O2?

Why Does My Young Female Patient Have Recurrent Spontaneous Pneumothoraces?

FA Manian MD, MPH, , , , , , , , , , , , Leave a comment

Causes of spontaneous pneumothorax are legion, including cigarette use, genetic predisposition, or most commonly subpleural bleb rupture. 1 However, in cases without an apparent cause, a young female patient with recurrent spontaneous pneumothorax should routinely be asked about the timing of the pneumothorax in relation to her menstrual periods.  If related, catamenial pneumothorax (CP)— also known as menses-associated pneumothorax—should also be considered.  

CP is commonly defined as 2 or more episodes of spontaneous pneumothoraces occurring within 72 hours of onset of menstruation. 2, 3 Classically, CP occurs in females between the ages of 30-40 years with a history of endometriosis and recurrent right-sided pneumothorax.

As for potential mechanisms to explain catamenial pneumothorax, several theories have been proposed, including the passage of air through the vagina and uterus during times of decreased cervical mucus production and peritoneal cavity into the pleural space via diaphragmatic fenestrations. 3 Another potential mechanism is the retrograde migration of endometrial tissue from the uterine lining via the right paracolic gutter into the pleural space through defects in the diaphragm. Endometrial necrosis following monthly cycles may then create air blebs and pneumothorax. 3,4 Although CP is the most common presentation of thoracic endometriosis, a diagnosis of endometriosis is not required for its diagnosis.3, 5

Initial evaluation of CP often includes chest X-ray, CT, or MRI which may show not only pneumothorax but also diaphragmatic nodules or fenestrations; CA-125 levels may also be elevated in CP due to endometriosis. 2,3,9  Endometriosis-related CP is diagnosed via video-assisted thoracoscopic surgery (VATS).  

Treatment includes surgical and medical options but, ultimately, the goal is to prevent recurrence which is more likely in CP compared to other pneumothoraces. 3, 6 Surgical approaches such as VATS, pleurodesis, and diaphragmatic plication or repair with mesh, may be considered but recurrence rates (8-40%) are common. 3,7 Treatment options also include hormone-suppression therapy resulting in atrophy of ectopic endometrial glands (eg, estrogen-progesterone oral contraceptives and gonadotropin-releasing-hormone [GNRH] agonists such as leuprolide). 2, 7

Bonus Pearl: Did you know that a condition called catamenial epilepsy also clusters around menstruation due to the diminished protective effect of progesterone against seizures?  10

Contributed by Mariam Krikorian, Medical Student (Lincoln Memorial University) Mercy Hospital-St. Louis

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References

  1. Sahn, Steven A., Heffer, John E. Spontaneous Pneumothorax. N Engl J Med. 2000;342:858-874. https://www-nejm-org.lmunet.idm.oclc.org/doi/10.1056/NEJM200003233421207?url_ver=Z39.88-2003&rfr_id=ori:rid:crossref.org&rfr_dat=cr_pub%20%200pubmed.
  2. Haga, T., Kumasaka, T., Kurihara, M, etal. Immunohistochemical Analysis of Thoracic Endometriosis. Path Intl, 2013;63(9);429-434. https://onlinelibrary.wiley.com/doi/10.1111/pin.12089.
  3. Visouli, A. N., Zarogoulidis, K., Kougioumtzi, I., etal. Catamenial Pneumothorax. J Thora Dis. 2014;6(4). https://jtd.amegroups.com/article/view/3205/html.
  4. Rousset-Jablonski, C., Alifano, M., Plu-Bureau, G., etal. A. Catamenial Pneumothorax and Endometriosis-Related Pneumothorax: Clinical Features and Risk Factors. Mol Hum Reprod. 2011;26(99);2322-2329. https://academic.oup.com/humrep/article/26/9/2322/720483.
  5. Korom, S., Canyurt, H., Missbach, A., etal. Catamenial Pneumothorax Revisited: Clinical Approach and Systematic Review of the Literature. J Thorac Cardiovasc Surgery. 2004;128(4);502-508. https://www.jtcvs.org/article/S0022-5223(04)00772-X/fulltext.
  6. Haga, T., Kurihara, M., Kataoka, H., etal. Clinical-Pathological Findings of Catamenial Pneumothorax: Comparison Between Recurrent Cases and Non-Recurrent Cases. Ann Thorac. 2014;202(6);202-206. https://www.jstage.jst.go.jp/article/atcs/20/3/20_oa.12.02227/_article.
  7. Leong, A. C., Coonar, A. S., Lang-Lazdunski, L. L. Catamenial Pneumothorax: Surgical Repair of the Diaphragm and Hormone Treatment. Ann R Coll Surg Engl. 2006;88(6). https://publishing.rcseng.ac.uk/doi/10.1308/003588406X130732.
  8. Marjański, T., Sowa, K., Czapla, A., etal. Catamenial Pneumothorax – A Review of the Literature. Polish Journal of Thoracic and Cardiovascular Surgery. 2016;13(2);117-121. https://www.termedia.pl/Catamenial-pneumothorax-a-review-of-the-literature,40,27920,0,1.html.
  9. Bagan, P., Le Pimpec Barthes, F., Assouad, J, etal. Catamenial Pneumothorax: Retrospective Study of Surgical Treatment. Ann Thorac. 2022;75(22);378-381. https://www.annalsthoracicsurgery.org/article/S0003-4975(02)04320-5/fulltext.
  10. Herzog, Andrew. Catamenial Epilepsy: Definition, Prevalence, Pathophysiology and Treatment. Elsevier Sci. 2008;17;151-159. https://pubmed-ncbi-nlm-nih-gov.lmunet.idm.oclc.org/18164632/.

 

Disclosures: The listed questions and answers are solely the responsibility of the author and do not necessarily represent the official views of Mercy Hospital-St. Louis, Massachusetts General Hospital, Harvard Catalyst, Harvard University, their affiliate academic healthcare centers, or its contributors. Although every effort has been made to provide accurate information, the author is far from being perfect. The reader is urged to verify the content of the material with other sources as deemed appropriate and exercise clinical judgment in the interpretation and application of the information provided herein. No responsibility for an adverse outcome or guarantees for a favorable clinical result is assumed by the author. Thank you!

Why Does My Young Female Patient Have Recurrent Spontaneous Pneumothoraces?

“Should I consider cardiac CT angiography in my 76-year-old male patient with chest pain of unclear origin?”  

FA Manian MD, MPH, , , , , , , , , , , , , , Leave a comment

Probably not!1-4 Although the 2021 AHA/ACC Chest Pain Guidelines have generally widened the scope of indications for cardiac CT angiography (CCTA) to patients at low to intermediate risk of coronary artery disease (CAD) presenting with acute coronary syndrome (ACS)1 (with or without known CAD), several caveats should be considered before ordering this test. In general preference is given to patients with the following characteristics: 

  • Age sixty-five years of age or younger.  Elderly are not ideal candidates for CCTA as the calcium burden may be too high, rendering the test non-diagnostic due to the interference with proper coronary artery lumen assessment. Women tend not to accumulate as much calcium and their age threshold may be increased to 70 years. Some studies like the ROMICAT II Trial extended the age up to 74 years.4 
  • BMI <40.2
  • Sinus rhythm. Atrial fibrillation can be circumvented with expanded padding techniques, albeit at higher radiation exposure.2
  • Without coronary stents, unless their stents are > 3.0 mm in diameter (eg, in left main, very proximal left anterior descending, circumflex or right coronary stents).2
  • Without high coronary calcium burden, or without multiple risk factors for CAD (eg, type 2 diabetes, hypertension, hyperlipidemia) in the setting of typical anginal chest pain.1
  • Other technical requirements: must be able to hold breath during procedure, not have contraindications to beta blockers (ideal heart rate <60 bpm), not have an iodinated contrast allergy, and have stable kidney function.2

Despite these caveats, many patients may still be able to undergo CCTA to help exclude coronary causes of their chest pain.  For example, a 49-year-old patient at low to intermediate risk of CAD presenting with atypical chest pain can potentially undergo CCTA and, if negative, be discharged the same day!4  

In our patient, however, given his older age, CCTA is likely to be non-diagnostic and proceeding to an alternative test, such as stress test or invasive coronary angiography (depending on circumstances and pre-test probability), may be a better option.  

Bonus Pearl: Did you know that, as a “bonus”,  CCTA provides a “free” look at the lungs, calcium score (used largely in asymptomatic patients to help weigh pros and cons of starting a statin)3, and other cardiopulmonary structures that may hint at alternative diagnoses for the cause of chest discomfort and/or dyspnea?

Contributed by Eldin Duderija MD, Cardiologist, Mercy Clinic, St. Louis, Missouri

 

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References:

  1. Gulati M, Levy P, et al. 2021 AHA/ACC/ASE/CHEST/SAEM/SCCT/SCMR Guideline for the Evaluation and Diagnosis of Chest Pain. J Am Coll Cardiol. 2021;78:e187–e285. https://pubmed.ncbi.nlm.nih.gov/34709879/
  2. Raff GL, Chinnaiyan KM, Cury RC, Garcia MT, Hecht HS, Hollander JE, O’Neil B, Taylor AJ, Hoffmann U; Society of Cardiovascular Computed Tomography Guidelines Committee. SCCT guidelines on the use of coronary computed tomographic angiography for patients presenting with acute chest pain to the emergency department: a report of the Society of Cardiovascular Computed Tomography Guidelines Committee. J Cardiovasc Comput Tomogr 2014;8:254-71. doi: 10.1016/j.jcct.2014.06.002. Epub 2014 Jun 12. PMID: 25151918. https://pubmed.ncbi.nlm.nih.gov/25151918/
  3. Hecht H, Blaha MJ, Berman DS, Nasir K, Budoff M, Leipsic J, Blankstein R, Narula J, Rumberger J, Shaw LJ. Clinical indications for coronary artery calcium scoring in asymptomatic patients: Expert consensus statement from the Society of Cardiovascular Computed Tomography. J Cardiovasc Comput Tomogr 2017;11:157-168. doi: 10.1016/j.jcct.2017.02.010. Epub 2017 Feb 24. PMID: 28283309. https://pubmed.ncbi.nlm.nih.gov/28283309/
  4. Hoffmann, Udo, et al. “Coronary CT angiography versus standard evaluation in acute chest pain.” N Engl J Med 2012;367:299-308. https://www.nejm.org/doi/full/10.1056/nejmoa1201161

Disclosures: The listed questions and answers are solely the responsibility of the author and do not necessarily represent the official views of Mercy Hospital-St. Louis, Massachusetts General Hospital, Harvard Catalyst, Harvard University, their affiliate academic healthcare centers, or its contributors. Although every effort has been made to provide accurate information, the author is far from being perfect. The reader is urged to verify the content of the material with other sources as deemed appropriate and exercise clinical judgment in the interpretation and application of the information provided herein. No responsibility for an adverse outcome or guarantees for a favorable clinical result is assumed by the author. Thank you!

 

“Should I consider cardiac CT angiography in my 76-year-old male patient with chest pain of unclear origin?”  

How do I assess the left ventricular (LV) systolic function by bedside point-of-care ultrasound (POCUS)?

FA Manian MD, MPH, , , , , , , , , , , , Leave a comment

You can assess the LV systolic function by POCUS by just zeroing in on the following cardiac parameters: 1. Anterior mitral valve leaflet motion in early diastole; 2. Change in LV chamber diameter; and 3. LV wall thickness during systole.1

First assess the anterior mitral valve leaflet motion towards the interventricular septum in early diastole in the parasternal long axis view (Figure). Estimated or measured distance between anterior mitral valve leaflet and the interventricular septum is called E-point septal separation (EPSS). When LV systolic function is normal, anterior mitral valve leaflet opens fully in early diastole, resulting in a small or minimal separation between it and the interventricular septum. Due to the fixed length of the chordae and the enlarged LV chamber size, anterior mitral valve leaflets are unable to fully open as systolic function worsens. This results in increased separation between the anterior mitral valve leaflet and the interventricular septum. An estimated EPSS greater than 10 mm is considered abnormal and suggests LV dysfunction.1,2

You can also estimate the LV ejection fraction (LVEF) quantitatively  by utilizing the following formula:3

LVEF (%)=75.5 – 2.5xEPSS (mm)

Keep in mind that aortic insufficiency and mitral stenosis can affect the accuracy of this formula.1

As for assessing the LV chamber diameter and wall thickness, recall that these parameters are also dynamic throughout the cardiac cycle. In systole, LV diameter should decrease by 30-40% while LV wall thickness should increase by approximately 40%. Using this as a guide, you can perform qualitative assessment by “eyeballing” the LV systolic function in parasternal long axis, parasternal short axis, apical 4-chamber and subcostal 4-chamber views. Beware that in parasternal long axis, apical 4-chamber and subcostal 4-chamber views, off axis of images can foreshorten the chamber size, resulting in overestimation of systolic function. Also be sure to use the midventricular papillary muscle view when assessing systolic function in the parasternal short axis.1   

Once you have obtained all the necessary images, feel free to categorize the systolic function as either “hyperdynamic”, “normal”, “reduced” or “severely reduced” (watch video below).1

Bonus pearl:  Did you know that qualitative assessment of the LV systolic function  following brief training sessions have been shown to significantly correlate with that obtained by formal echocardiography (k = 0.77, p <0.001).1,4,5 

Contributed by Woo Moon, D.O, Director POCUS Training Program, Mercy-St. Louis Hospital, St. Louis, Missouri

Figure: EPSS in normal vs reduced EF 

Note: EPSS (yellow arrows) is narrow in normal but wide in reduced EF

Video: Four categories of systolic function

 

References

  1. Soni MD MS NJ, Arntfield MD FRCPC R, Kory MD MPA P. Point of Care Ultrasound. 2nd ed. St. Louis, MO: Elsevier; 2019. . https://www.elsevier.com/books/point-of-care-ultrasound/soni/978-0-323-54470-2
  2. Kimura BJ, Yogo N, O’Connell CW, Phan JN, Showalter BK, Wolfson T. Cardiopulmonary limited ultrasound examination for “quick-look” bedside application. Am J Cardiol 2011;108(4):586–90. https://linkinghub.elsevier.com/retrieve/pii/S0002-9149(11)01424-X
  3. Silverstein JR, Laffely NH, Rifkin RD. Quantitative estimation of left ventricular ejection fraction from mitral valve E-point to septal separation and comparison to magnetic resonance imaging. Am J Cardiol 2006;97(1):137–40. https://www.ajconline.org/article/S0002-9149(05)01683-8/fulltext
  4. Melamed R, Sprenkle MD, Ulstad VK, Herzog CA, Leatherman JW. Assessment of left ventricular function by intensivists using hand-held echocardiography. Chest 2009;135(6):1416–20. https://journal.chestnet.org/article/S0012-3692(09)60341-X/fulltext 
  5. Johnson BK, Tierney DM, Rosborough TK, Harris KM, Newell MC. Internal medicine point-of-care ultrasound assessment of left ventricular function correlates with formal echocardiography. J Clin Ultrasound 2016;44(2):92–9. https://onlinelibrary.wiley.com/doi/10.1002/jcu.22272

 

 

 

 

 

 

 

How do I assess the left ventricular (LV) systolic function by bedside point-of-care ultrasound (POCUS)?

My patient presents for evaluation of a mole on her arm. What features of the mole should I look for to help me distinguish a benign mole from melanoma?

FA Manian MD, MPHLeave a comment

Great question! Identifying a melanoma is a lot easier than you might think. A good starting point is the ABCDE criteria, which stands for Asymmetry, Border irregularity, Color variation, Diameter > 6 mm/Dark, and Evolution over time (see Fig 1 below). 1 Higher number of these characteristics in a particular lesion increases the probability of it being melanoma. For example, in the presence of just one characteristic, the positive likelihood ratio (LR) is 1.5 with the probability of melanoma of 7.4%. However, if all five characteristics are present, the positive LR rises to 107, while the probability of melanoma increases to 85%. 2,3,4

Another useful trick is looking for the “ugly duckling sign” (UDS), which refers to any pigmented lesion that appears obviously different than others on a patient’s body.5 For example, let’s say you’re seeing a patient with multiple small, circular, equally-sized moles on his forearm. A few inches away, he has a significantly larger mole with an irregular border. This would qualify as a positive UDS.  While the sensitivities of melanoma recognition are similar for the UDS and the ABCDE criteria (100% and 99%, respectively), the UDS has been shown to significantly improve specificity (88.3%) and accuracy (90.9%) when compared to the ABCDE criteria alone (57.4% and 66.7 %, respectively).6 So incorporating both sets of criteria into your approach to melanoma recognition may be prudent.

Once you suspect a melanoma, your should refer your patient to a dermatologist for an excisional biopsy, the gold standard for melanoma diagnosis.  This procedure consists of excising the entire lesion with 1-3 mm margins.7 The resulting sample can then be used to histologically confirm the diagnosis, prognosticate, and guide management.

Primary care providers play a crucial role in the early detection and treatment of melanoma, so keep your eyes open for any “unusual” looking moles, even if you’re seeing a patient for something unrelated!

Bonus Pearl

Did you know that cardiac involvement with melanoma is not uncommon, affecting an estimated 28% to 56% of patients with metastatic melanoma? 8

 

Figure 1: ABCDE criteria to help differentiate benign skin lesions from melanoma

i

 From Pawan Sonawane, Sahel Shardhul, Raju Mendhe, “Cloud based mobile solution for early detection of Skin Cancer using Artificial Intelligence”, International Journal of Scientific Research in Computer Science, Engineering and Information Technology (IJSRCSEIT), ISSN : 2456-3307, Volume 7 Issue 3, pp. 312-324, May-June 2021. Available at doi : https://doi.org/10.32628/CSEIT217327 Journal URL : https://ijsrcseit.com/CSEIT217327 (https://www.researchgate.net/publication/352394140_Cloud_based_mobile_solution_for_early_detection_of_Skin_Cancer_using_Artificial_Intelligence)

Contributed by Aditya Nellore, 4th year Medical Student, St. Louis University Medical School, St. Louis, Missouri

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References:

  1. Goldsmith SM. Why Is Darkness an Essential Feature for Melanoma Recognition? Skinmed. 2021 Oct 1;19(5):334-336. PMID: 34861912. (https://pubmed.ncbi.nlm.nih.gov/34861912/)
  2. Duarte AF, Sousa-Pinto B, Azevedo LF, Barros AM, Puig S, Malvehy J, Haneke E, Correia O. Clinical ABCDE rule for early melanoma detection. Eur J Dermatol. 2021 Dec 1;31(6):771-778. doi: 10.1684/ejd.2021.4171. PMID: 35107069. (https://pubmed.ncbi.nlm.nih.gov/35107069/)
  3. Thomas L, Tranchand P, Berard F, Secchi T, Colin C, Moulin G. Semiological value of ABCDE criteria in the diagnosis of cutaneous pigmented tumors. Dermatology. 1998;197(1):11-7. doi: 10.1159/000017969. PMID: 9693179. (https://pubmed.ncbi.nlm.nih.gov/9693179/)
  4. Ebell M. Clinical diagnosis of melanoma. Am Fam Physician. 2008 Nov 15;78(10):1205, 1208. PMID: 19035070. (https://pubmed.ncbi.nlm.nih.gov/19035070/)
  5. Gaudy-Marqueste C, Wazaefi Y, Bruneu Y, Triller R, Thomas L, Pellacani G, Malvehy J, Avril MF, Monestier S, Richard MA, Fertil B, Grob JJ. Ugly Duckling Sign as a Major Factor of Efficiency in Melanoma Detection. JAMA Dermatol. 2017 Apr 1;153(4):279-284. doi: 10.1001/jamadermatol.2016.5500. PMID: 28196213. (https://pubmed.ncbi.nlm.nih.gov/28196213/)
  6. Ilyas M, Costello CM, Zhang N, Sharma A. The role of the ugly duckling sign in patient education. J Am Acad Dermatol. 2017 Dec;77(6):1088-1095. doi: 10.1016/j.jaad.2017.06.152. Epub 2017 Sep 28. PMID: 28964538. (https://pubmed.ncbi.nlm.nih.gov/28964538/)
  7. Swetter SM, Tsao H, Bichakjian CK, Curiel-Lewandrowski C, Elder DE, Gershenwald JE, Guild V, Grant-Kels JM, Halpern AC, Johnson TM, Sober AJ, Thompson JA, Wisco OJ, Wyatt S, Hu S, Lamina T. Guidelines of care for the management of primary cutaneous melanoma. J Am Acad Dermatol. 2019 Jan;80(1):208-250. doi: 10.1016/j.jaad.2018.08.055. Epub 2018 Nov 1. PMID: 30392755. (https://pubmed.ncbi.nlm.nih.gov/30392755/)
  8. Goldberg AD, Blankstein R, Padera RF. Tumors metastatic to the heart. Circulation. 2013 Oct 15;128(16):1790-4. doi: 10.1161/CIRCULATIONAHA.112.000790. PMID: 24126323. (https://pubmed.ncbi.nlm.nih.gov/24126323/)

Disclosures: The listed questions and answers are solely the responsibility of the author and do not necessarily represent the official views of Mercy Hospital-St. Louis, Massachusetts General Hospital, Harvard Catalyst, Harvard University, their affiliate academic healthcare centers, or its contributors. Although every effort has been made to provide accurate information, the author is far from being perfect. The reader is urged to verify the content of the material with other sources as deemed appropriate and exercise clinical judgment in the interpretation and application of the information provided herein. No responsibility for an adverse outcome or guarantees for a favorable clinical result is assumed by the author. Thank you!

 

My patient presents for evaluation of a mole on her arm. What features of the mole should I look for to help me distinguish a benign mole from melanoma?

My elderly hospitalized patient with pneumonia has developed hypoglycemia within days of initiating piperacillin/tazobactam (Zosyn). Is there a connection between piperacillin/tazobactam and hypoglycemia?

FA Manian MD, MPH, , , , , , , , , , , , , , Leave a comment

Hypoglycemia is a rare (<1%) reported side effect of piperacillin/tazobactam (P/T) [1].  While the exact mechanism is unclear, hypoglycemia in this setting may be related to the adverse impact of P/T on renal function or possibly competitive inhibition of renal organic anion transporter 3 (OAT3).

The association of P/T with acute kidney injury (AKI) is well known. In a retrospective cohort analysis of 11,650 patients, P/T was associated with AKI in 7.8% of patients [2]. Of interest, compared to other antibiotics, P/T has also been shown to delay renal recovery in critically ill patients [3].  Decline in renal function may in turn reduce clearance of insulin and lead to hypoglycemia, particularly in patients who already have risk factors for hypoglycemia, such as malnutrition [4]. This is not surprising because renal clearance accounts for 25% of insulin clearance (rest is hepatic).  

Another plausible mechanism is the impact of P/T on glucose metabolism through competitive inhibition of OAT3 [5]. OAT3 is important in reabsorption of gluconeogenic precursors as well as excretion of uremic metabolites [6], which may further dysregulate hepatic gluconeogenesis and precipitate hypoglycemia. Fascinating!

Bonus pearl: Did you know that elderly patients may be at risk of reactive (post-prandial) hypoglycemia particularly in the setting of pre-diabetes or diabetes due to loss of coordination between glucose load and insulin secretion [7]? 

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Contributed by Michael Nance, MD, PhD, Department of Medicine, Mercy Hospital-St. Louis, St. Louis, Missouri

References:

  1. Wyeth Pharmaceutical Inc. Zosyn (piperacillin/tazobactam) [package insert]. U.S. Food and Drug Administration website. https://www.accessdata.fda.gov/drugsatfda_docs/label/2017/050684s88s89s90_050750s37s38s39lbl.pdf. Revised May 2017. Accessed January 16, 2021.
  2. Rutter WC, Burgess DR, Talbert JC, Burgess DS. Acute kidney injury in patients treated with vancomycin and piperacillin-tazobactam: A retrospective cohort analysis. J Hosp Med. 2017 Feb;12(2):77-82. doi: 10.12788/jhm.2684. PMID: 28182801; PMCID: PMC5573255. https://pubmed.ncbi.nlm.nih.gov/28182801/
  3. Jensen JS, Hein L, Lundgren B, et al. Kidney failure related to broad-spectrum antibiotics in critically ill patients: secondary end point results from a 1200 patient randomised trial. BMJ Open 2012;2:doi: 10.1136/bmjopen-2011-000635  https://bmjopen.bmj.com/content/2/2/e000635
  4. Leibovitz E, Adler H, Giryes S, Ditch M, Burg NF, Boaz M. Malnutrition risk is associated with hypoglycemia among general population admitted to internal medicine units. Results from the MENU study. Eur J Clin Nutr. 2018 Jun;72(6):888-893. doi: 10.1038/s41430-018-0143-9. Epub 2018 Mar 27. PMID: 29588529. https://pubmed.ncbi.nlm.nih.gov/29588529/
  5. Wen S, Wang C, Duan Y, Huo X, Meng Q, Liu Z, Yang S, Zhu Y, Sun H, Ma X, Yang S, Liu K. OAT1 and OAT3 also mediate the drug-drug interaction between piperacillin and tazobactam. Int J Pharm. 2018 Feb 15;537(1-2):172-182. doi: 10.1016/j.ijpharm.2017.12.037. Epub 2017 Dec 23. PMID: 29277663. https://pubmed.ncbi.nlm.nih.gov/29277663/
  6. Wu, W., Bush, K.T. & Nigam, S.K. Key Role for the Organic Anion Transporters, OAT1 and OAT3, in the in vivoHandling of Uremic Toxins and Solutes. Sci Rep 7, 4939 (2017). https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5504054/
  7. Tamura Y, Araki A, Chiba Y, Horiuchi T, Mori S, Hosoi T. Postprandial reactive hypoglycemia in an oldest-old patient effectively treated with low-dose acarbose. Endocr J. 2006 Dec;53(6):767-71. doi: 10.1507/endocrj.k05-140. Epub 2006 Sep 12. PMID: 16966825. https://pubmed.ncbi.nlm.nih.gov/16966825/ 

Disclosures: The listed questions and answers are solely the responsibility of the author and do not necessarily represent the official views of Mercy Hospital-St. Louis, Massachusetts General Hospital, Harvard Catalyst, Harvard University, their affiliate academic healthcare centers, or its contributors. Although every effort has been made to provide accurate information, the author is far from being perfect. The reader is urged to verify the content of the material with other sources as deemed appropriate and exercise clinical judgment in the interpretation and application of the information provided herein. No responsibility for an adverse outcome or guarantees for a favorable clinical result is assumed by the author. Thank you!

My elderly hospitalized patient with pneumonia has developed hypoglycemia within days of initiating piperacillin/tazobactam (Zosyn). Is there a connection between piperacillin/tazobactam and hypoglycemia?

Is there a connection between eosinophils and sickle cell anemia?

FA Manian MD, MPH, , , , , , , , Leave a comment

Patients with sickle cell anemia (SCA) frequently (~55%) demonstrate absolute eosinophil count (AEC) (>450 cells/uL) during non-crisis steady state without significant change during sickle cell crisis [1-4]. Although the exact mechanism for this finding is not clear, it may be related to elevated plasma levels of circulating factors such as eotaxin, IL-5, and GM-CSF in SCA [2,3].

Cumulative data from 3 independent cross-sectional studies involving 131 SCA patients reported a mean AEC of ~498 cells/u (range 490-504 cells/uL) when not in crisis [2,3,6]. Surprisingly, two additional studies evaluating 200 patients did not observe a significant difference in AEC between steady- and crisis-states [1,4].

The significance of elevated AEC in patients with SCA is unclear. Of interest, several studies of eosinophils isolated from patients with SCA have demonstrated increased eosinophil adhesion to blood vessels, degranulation, and reactive oxygen species production compared to healthy controls [5,6]. In another study, hydroxyurea was shown to reduce eosinophil adhesion and degranulation [2].

While it is unknown whether eosinophils directly contribute to the development of vaso-occlusive crisis, these studies suggest eosinophils may be an important therapeutic target in SCA. 

Bonus pearl: Did you know that low eosinophil count may help predict infection in SCA patients? A retrospective study of SCA patients with and without infection showed that relative eosinopenia (0.025 compared to 0.2 x 109 cells/L) was highly sensitive (100%) and specific (93.3%) for infection [7].

Contributed by Michael Nance MD, PhD, Department of Medicine, Mercy Hospital-St. Louis, St. Louis, Missouri

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References:

  1. Ekeke GI. Sickle cell disease: some haematological changes in steady state and crisis. Biomed Biochem Acta 1987; 46:S197-S201. https://pubmed.ncbi.nlm.nih.gov/3593298/
  2. Pallis FR, Nicola Conran, Kleber Yotsumoto Fertrin, Sara T. Olalla-Saad, Fernando Ferreira Costa, Carla Fernanda Franco-Penteado; Altered Functional Properties of Eosinophils In Sickle Cell Anemia and Effects of Hydroxyurea Therapy. Blood 2010; 116 (21): 2656. https://doi.org/10.1182/blood.V116.21.2656.2656
  3. Conran N, Saad ST, Costa FF, Ikuta T. Leukocyte numbers correlate with plasma levels of granulocyte-macrophage colony-stimulating factor in sickle cell disease. Ann Hematol. 2007; 86(4):255-261. https://pubmed.ncbi.nlm.nih.gov/17205286/
  4. Klouda T, Raybagkar D, Bernstein B, Apollonsky N, “Changes in Blood Profile from Steady State in Patients with Sickle Cell Anemia Admitted for Vaso-occlusive Crisis and Acute Chest Syndrome”, Advances in Hematology, vol. 2020, Article ID 3656717, 5 pages, 2020. https://doi.org/10.1155/2020/3656717
  5. Canalli AA, Conran N, Fattori A, Saad ST, Costa FF. Increased adhesive properties of eosinophils in sickle cell disease. Exp Hematol. 2004; 32(8):728-734. https://pubmed.ncbi.nlm.nih.gov/15308324/
  6. Pallis FR, Conran N, Fertrin KY, Olalla Saad ST, Costa FF, Franco-Penteado CF. Hydroxycarbamide reduces eosinophil adhesion and degranulation in sickle cell anaemia patients. Br J Haematol. 2014; 164(2):286-295. https://pubmed.ncbi.nlm.nih.gov/24383847/
  7. Ahmed, SG and Uraka, A. Eosinopenia as a marker of infection in patients with sickle cell anemia: A preliminary report. Int. J. Biomed. Health Sci. 2010. 6(1):57-61. http://www.ojs.klobexjournals.com/index.php/ijbhs/article/viewFile/671/741

 

Disclosures: The listed questions and answers are solely the responsibility of the author and do not necessarily represent the official views of Mercy Hospital-St. Louis, Massachusetts General Hospital, Harvard Catalyst, Harvard University, their affiliate academic healthcare centers, or its contributors. Although every effort has been made to provide accurate information, the author is far from being perfect. The reader is urged to verify the content of the material with other sources as deemed appropriate and exercise clinical judgment in the interpretation and application of the information provided herein. No responsibility for an adverse outcome or guarantees for a favorable clinical result is assumed by the author. Thank you!

Is there a connection between eosinophils and sickle cell anemia?

Can I have some tips on how to improve my PowerPoint presentation?

FA Manian MD, MPH, , , , Leave a comment

Effective or “high value” PowerPoint presentations take some planning and work. Here are some tips (by no means comprehensive) on how you can improve your PowerPoint presentation,1-4 divided into 4 stages:

Stage I: Planning for your talk

    • “Know your stuff”
    • Prioritize the main objectives of your talk given time  constraints ie, “What would you like your audience to really take away from your talk?”
    • Accept the fact that you will not be able to cover all that you know about the topic during the allotted time
    • Think about how you might keep your audience engaged throughout your talk as you introduce topics and concepts!

Stage II: Preparing your slides

  1. General rules
    • Keep them simple (“Less is more”)
      • Minimize number of slides eg, average no more than 1 slide/min
      • Minimize number of concepts/slide eg,1/slide
      • Minimize clutter 
    • Avoid “apologetic” slides ie, if not easily readable or visible or “too busy”, don’t use them!
    • Practice, practice, practice and edit as needed
  2.  Text
    • Minimize number of words/slide eg, 6×6 rule, maximum 6 words/line, 6 lines/slide
    • Use easily readable font types and sizes
      1. Minimum 24 for small rooms
      2. Minimum 36 for larger rooms
      3. If not readable 10 feet away from monitor, don’t include
    • Check spelling!
    • Choose high contrast colors between background and text eg, black text on white, yellow on dark blue background, not red on green
  3. Tables
    • Avoid reproduction of large tables with tons of data that cannot be read or can easily overwhelm the audience
    • If you use large tables, zero in on a particular section and display a magnified version of that section so that the audience can follow along with you

Stage III: Presenting your talk

  • Remember, you are the presenter, not PowerPoint
  • Engage the audience from the beginning to the end
    • Beginning: Use a “hook” ie, why should the audience be interested in your talk?
    • During
      • Maintain eye contact with the audience
      • Be dynamic/animate
      • Use speech intonations as if you are having a conversation with the audience
      • Do not read slides word-by-word
    • End: Highlight your take-home points eg, “if you don’t remember anything else…”

Stage IV: Post-Presentation

  • Ask for feedback from colleagues, audience, coordinators, etc… 
  • Self-reflect ie, what went well, what didn’t go so well?
  • Apply lessons learned to your next PowerPoint presentation!

Five take-home points for this pearl

  • Less is more, keep your presentation clear and simple
  • Time is limited; prioritize your message
  • Keep your audience engaged throughout the talk
  • Conclude with take-home points
  • Practice, practice, practice

Bonus Pearl: Did you know that people generally remember 20% of what they hear, 30% of what they see, and 50% of what they see and hear? 2

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References

  1. Collins J, et al. Evaluation of speakers at a national radiology continuing medical education course. Med Educ Online 2002;7:17 https://pubmed.ncbi.nlm.nih.gov/28253766/ 
  2. Collins J. Education techniques for lifelong learning. RadioGraphics 2004;24:1177-83. https://pubmed.ncbi.nlm.nih.gov/15256637/ 
  3. Harolds JA. Tips for giving a memorable presentation, Part IV. Using and composing PowerPoint slides. Current Nuclear Medicine 2012;37:977-80. https://pubmed.ncbi.nlm.nih.gov/22899205/ 
  4. Grech V. WASP (write a scientific paper):Optimization of PowerPoint presentations and skills. Early Human Development 2018;125:53-56.https://pubmed.ncbi.nlm.nih.gov/29929910/ 

Disclosures: The listed questions and answers are solely the responsibility of the author and do not necessarily represent the official views of Mercy Hospital-St. Louis, Massachusetts General Hospital, Harvard Catalyst, Harvard University, their affiliate academic healthcare centers, or its contributors. Although every effort has been made to provide accurate information, the author is far from being perfect. The reader is urged to verify the content of the material with other sources as deemed appropriate and exercise clinical judgment in the interpretation and application of the information provided herein. No responsibility for an adverse outcome or guarantees for a favorable clinical result is assumed by the author. Thank you!

Can I have some tips on how to improve my PowerPoint presentation?

Why doesn’t my patient with lactic acidosis have hyperkalemia?

FA Manian MD, MPH, , , , , , , , , , , , , , , , , Leave a comment

Although hyperkalemia may be observed in a variety of conditions associated with metabolic acidosis, it is less likely to be seen in conditions associated with excess organic acids (eg, in lactic acidosis or diabetic ketoacidosis). A likely explanation for this finding revolves around the amazing organic anion transporter (OAT) and its attendant role in counteracting hyperkalemia by bringing potassium (K+) back into the cells.1-5 See details of impact of extracellular and intracellular pH on K+ homeostasis in Figure.1 

Recall that in metabolic acidosis the increased concentration of hydrogen ion (H+) outside the cell reduces sodium (Na+) influx into cells through the Na+-H+ exchange channel resulting in a drop in the intracellular Na+.  Since the Na+K+ATPase ion channel depends on the intracellular Na+ for bringing K+ into the cells, the end-result is higher K+ concentrations in the extracellular space, potentially resulting in hyperkalemia.  This is what is often seen in conditions of mineral (non-organic) acid excess (eg, in respiratory acidosis or poor renal function).

In the case of organic acidosis, however, the OAT also plays an important factor in K+ homeostasis (Figure)1.  As the name suggests, this transporter allows  organic acids such as lactic acid or ketones to enter the cell. As the H+ concentration increases intracellularly, there is more Na+-H+ exchange and more influx of Na+ into the cell.  More available Na+ intracellularly means more Na+ is pumped out by Na+K+ATPase, and more K+ is brought into the cell,1-5 mitigating the impact of metabolic acidosis on K+ efflux into the  extracellular space and potentially even causing hypokalemia! 

Concurrent hyperkalemia and lactic acidosis or diabetic ketoacidosis may of course still occur.  However, in such cases, hyperkalemia is often due to an epiphenomenon related to complicating factors.  In the case of lactic acidosis, this may be related to concurrent renal dysfunction,3 while in diabetic ketoacidosis it may be related to hyperosmolarity or insulin deficiency.1

So next time you see a patient who has hyperkalemia and lactic acidosis, ask yourself  “What else am I missing that can explain the hyperkalemia?“.

Bonus Pearl

Did you know that lactic acid in human blood was first discovered by the German physician–chemist, Johann Joseph Sherer, who sampled post-mortem blood from 2 women who died of puerperal fever in 1843? 6

Contributed by Nabi Chaudhri-Martinez MD, Mercy Hospital-St. Louis, St. Louis, Missouri

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References:

  1. Aronson PS, Giebisch G. Effects of pH on potassium: new explanations for old observations. J Am Soc Nephrol. 2011 Nov;22(11):1981-9. doi: 10.1681/ASN.2011040414. Epub 2011 Oct 6. PMID: 21980112; PMCID: PMC3231780. https://jasn.asnjournals.org/content/22/11/1981.long
  2. Orringer CE, Eustace JC, Wunsch CD, Gardner LB. Natural history of lactic acidosis after grand-mal seizures. A model for the study of an anion-gap acidosis not associated with hyperkalemia. N Engl J Med. 1977 Oct 13;297(15):796-9. doi: 10.1056/NEJM197710132971502. PMID: 19702. https://www.nejm.org/doi/10.1056/NEJM197710132971502?url_ver=Z39.88-2003&rfr_id=ori:rid:crossref.org&rfr_dat=cr_pub%20%200pubmed
  3. Fulop M. Serum potassium in lactic acidosis and ketoacidosis. N Engl J Med. 1979 May 10;300(19):1087-9. doi: 10.1056/NEJM197905103001905. PMID: 34793. https://www.nejm.org/doi/10.1056/NEJM197905103001905?url_ver=Z39.88-2003&rfr_id=ori:rid:crossref.org&rfr_dat=cr_pub 0pubmed
  4. Adrogué HJ, Madias NE. Changes in plasma potassium concentration during acute acid-base disturbances. Am J Med. 1981 Sep;71(3):456-67. doi: 10.1016/0002-9343(81)90182-0. PMID: 7025622. https://www.amjmed.com/article/0002-9343(81)90182-0/pdf
  5. Nigam SK, Bush KT, Martovetsky G, et al. The organic anion transporter (OAT) family: A systems biology perspective. Physiol Rev 2015;95:83:123. The Organic Anion Transporter (OAT) Family: A Systems Biology Perspective (physiology.org)
  6. Kompanje EJ, Jansen TC, van der Hoven B, Bakker J. The first demonstration of lactic acid in human blood in shock by Johann Joseph Scherer (1814-1869) in January 1843. Intensive Care Med. 2007;33(11):1967-1971. doi:10.1007/s00134-007-0788-7 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2040486/

Disclosures: The listed questions and answers are solely the responsibility of the author and do not necessarily represent the official views of Mercy Hospital-St. Louis, Massachusetts General Hospital, Harvard Catalyst, Harvard University, their affiliate academic healthcare centers, or its contributors. Although every effort has been made to provide accurate information, the author is far from being perfect. The reader is urged to verify the content of the material with other sources as deemed appropriate and exercise clinical judgment in the interpretation and application of the information provided herein. No responsibility for an adverse outcome or guarantees for a favorable clinical result is assumed by the author. Thank you!

Why doesn’t my patient with lactic acidosis have hyperkalemia?