ARB and uricosuric effect

Q: Which of the following angiotensin II receptor blocker (ARB) has a direct uricosuric effect? (select one)

A) Losartan 

B) Candesartan 

C) Valsartan 

D) Irbesartan 

E) Olmesartan 

Answer: A

Angiotensin-converting enzyme (ACE) inhibitors and angiotensin II receptor blockers (ARBs) decrease the serum uric acid level. The mechanism of action is by revering the stimulatory effect of angiotensin II on proximal sodium and urate reabsorption. Moreover, out of all, losartan is found to have a direct uricosuric effect.

It may be of interest to clinicians that a combination of losartan or any ACE inhibitor with a thiazide diuretic has shown a better blood control effect and minimizes the side effects such as hypokalemia and/or hyperlipidemia.

#pharmacology

References:

1. Weinberger MH. Influence of an angiotensin converting-enzyme inhibitor on diuretic-induced metabolic effects in hypertension. Hypertension 1983; 5:III132.

2. Soffer BA, Wright JT Jr, Pratt JH, et al. Effects of losartan on a background of hydrochlorothiazide in patients with hypertension. Hypertension 1995; 26:112.

3. Manolis AJ, Grossman E, Jelakovic B, et al. Effects of losartan and candesartan monotherapy and losartan/hydrochlorothiazide combination therapy in patients with mild to moderate hypertension. Losartan Trial Investigators. Clin Ther 2000; 22:1186.

4. Shahinfar S, Simpson RL, Carides AD, et al. Safety of losartan in hypertensive patients with thiazide-induced hyperuricemia. Kidney Int 1999; 56:1879.

Mg in COPD

Q: Intravenous Magnesium (IV Mg) can be given in severe exacerbation of COPD? (select one)

A) as a bolus

B) over 20 minutes

C) over an hour

D) as continuous infusion

Answer: B

Magnesium sulfate has a Grade C recommendation for use as an adjuvant treatment in severe COPD exacerbation, particularly when response to short-acting inhaled bronchodilators is not robust. A single dose of 2 grams IV Mg can be given over 20 minutes. IV Mg has bronchodilator activity. It inhibits calcium influx into the airway smooth muscle cells. It shows some evidence of decreased hospitalizations in COPD exacerbations.

#pulmonary

References:

1. Gourgoulianis KI, Chatziparasidis G, Chatziefthimiou A, Molyvdas PA. Magnesium as a relaxing factor of airway smooth muscles. J Aerosol Med 2001; 14:301.

2. Ni H, Aye SZ, Naing C. Magnesium sulfate for acute exacerbations of chronic obstructive pulmonary disease. Cochrane Database Syst Rev 2022; 5:CD013506.

3. Kew KM, Kirtchuk L, Michell CI. Intravenous magnesium sulfate for treating adults with acute asthma in the emergency department. Cochrane Database Syst Rev 2014; :CD010909.

Nails in hyperthyroidism

Q: In hyperthyroidism, nails tend to get? (select one)

A) hard

B) soft

Answer: B

Physical exam plays an integral part in hyperthyroidism. Skin tends to be warm and possibly erythematous due to increased blood flow. Also, it becomes smoother due to thinning keratin layer. Onycholysis is a common finding in hyperthyroidism. Hyperpigmentation is usually evident due to accelerated cortisol metabolism, leading to increased corticotropin (ACTH) secretion.

Vitiligo, alopecia areata, and thinning of the hair may also occur.

#endocrinology

#physical exam

References:

1. Heymann WR. Cutaneous manifestations of thyroid disease. J Am Acad Dermatol 1992; 26:885.

2. KIRKEBY K, HANGAARD G, LINGJAERDE P. THE PIGMENTATION OF THYROTOXIC PATIENTS. Acta Med Scand 1963; 174:257.

3. Collet E, Petit JM, Lacroix M, et al. [Chronic urticaria and autoimmune thyroid diseases]. Ann Dermatol Venereol 1995; 122:413.

Metronidazole vs Clindamycin CSF penetration

Q: Which of the following drug can cross blood-brain barrier more effectively? (pick one)

A) Metronidazole

B) Clindamycin

Answer: A

Although metronidazole and clindamycin both cover anaerobes, metronidazole penetrates the blood-brain barrier better. The penetration is about 45-50 percent. This makes metronidazole a preferred choice in brain abscesses. Moreover, metronidazole also distributes well into muscle tissues and is a good choice in patients with sepsis or undergoing surgery.

#pharmacology

References:

Warner JF, Perkins RL, Cordero L. Metronidazole therapy of anaerobic bacteremia, meningitis, and brain abscess. Arch Intern Med 1979; 139:167.

Karjagin J, Pähkla R, Karki T, Starkopf J. Distribution of metronidazole in muscle tissue of patients with septic shock and its efficacy against Bacteroides fragilis in vitro. J Antimicrob Chemother 2005; 55:341.

Karjagin J, Pähkla R, Starkopf J. Perioperative penetration of metronidazole into muscle tissue: a microdialysis study. Eur J Clin Pharmacol 2004; 59:809.

cyanosis in methemoglobinemia

Q: How does cyanosis correlate with hemoglobin in methemoglobinemia?

Answer: In methemoglobinemia, cyanosis correlates with total amount of methemoglobin. The formula is

total hemoglobin x percent methemoglobin = total methemoglobin

Once the total methemoglobin >1.5 g/dL,  cyanosis occurs

●A patient with total hemoglobin of 9 g/dL who has 10 percent of methemoglobin will have total methemoglobin of 0.9 g/dL and will not be cyanotic.

●A patient with total hemoglobin of 16 g/dL who has 10 percent methemoglobin will have total methemoglobin of 1.6 g/dL and will be cyanotic.

In other words, anemia can mask cyanosis. This is why some individuals with acquired methemoglobinemia in anemia can be quite ill despite lack of cyanosis. 

#hematology

Reference:

Josef T Prchal- Methemoglobinemia - © 2022 UpToDate ; Link: https://www.uptodate.com/contents/methemoglobinemia

Treating Dig toxicity

Case: 74 years old male has been found to have arrhythmia with runs of wide complex ventricular tachycardia. The patient so far has remained hemodynamically stable. A crash cart is called near the bed, pads are applied to the chest, and STAT labs are sent. A review of the chart showed that: 4 days ago digoxin level was 1.9, and since then patient's serum creatinine level is steadily rising from 1.6 to 2.8. "Dig. toxicity" is suspected. STAT dig. level is ordered. Indeed, Dig. level is back with 3.4, and accompanied labs showed a K+ level of 6.9. "Digi-bind" (Digoxin Immune Fab) is ordered. Interim, the medical resident, ordered the following regimen to treat hyperkalemia: IV insulin, D-50, IV bicarb., IV calcium, and albuterol neb.. Pharmacy informed, "IV calcium is not available." What other electrolytes can be used instead of calcium to stabilize the cardiac membrane in hyperkalemia?

Answer: IV Magnesium

Some literature has shown a similar membrane stabilizing effect from magnesium and may be used instead of calcium in hyperkalemia. 

Also, caution should be sought not to treat hyperkalemia aggressively, or at least the potassium level should be followed very closely, particularly when DigiFab administration is planned. 

Digoxin causes a shift of potassium from inside to outside of the cell and may cause severe serum hyperkalemia, though overall, there is a whole-body deficit of potassium. With the administration of DigiFab (Digibind), potassium shifts back into the cell, and life-threatening serum hypokalemia may ensue rapidly.

#cardiology

#pharmacology

References: 

 1. Slow-release potassium overdose: Is there a role for magnesium? Emergency Medicine 1999;11:263–71

2. Kinlay S, Buckley NA. Magnesium sulfate in the treatment of ventricular arrhythmias due to digoxin toxicity. J Toxicol Clin Toxicol. 1995;33(1):55-9. doi: 10.3109/15563659509020216. PMID: 7837314.

Thanksgiving

 

Thiazide diuretics and urinary calcium excretion

Q: Thiazide diuretics _________ urinary calcium excretion? (select one)

A) increases

B) decreases

Answer: B

Thiazide diuretics decrease urinary calcium excretion. This effect makes it a good choice for patients who develop recurrent calcium nephrolithiasis. Also, it can be used in patients with any other cause of hypercalciuria. Although unlikely, patients already on thiazide diuretics should be watched for hypercalcemia, particularly those with underlying hyperparathyroidism.

#electrolytes

#pharmacology

Reference:

Grieff M, Bushinsky DA. Diuretics and disorders of calcium homeostasis. Semin Nephrol. 2011 Nov;31(6):535-41. doi: 10.1016/j.semnephrol.2011.09.008. PMID: 22099510.

Labetalol

Q: Labetalol is an alpha-1 and ___________ beta-1 blocker? (select one)

A) selective

B) Non-selective

Answer: B

Labetalol is an alpha-1 and non-selective b1 blocker. It can be used in acute aortic dissection, acute myocardial ischemia, acute ischemic stroke/intracerebral bleed, eclampsia/preeclampsia, and hypertensive encephalopathy. It can be given as bolus doses or continuous infusion.

• For bolus doses: 20mg IV can be administrated with an incremental dose of 20-80mg every 10 minutes until the blood pressure (BP) target is achieved
• For continuous infusion: Loading dose 20mg IV is followed by 1-2 mg/min, which can be titrated up until the BP target is achieved

Max dose is 300mg over 24 hours. The onset of action is within 2-5 minutes, and the duration of action is 2-4 hours

Due to its alpha-1 blocking effect, it reduces the SVR without reducing total peripheral blood flow. It should be given with caution in patients with heart failure, sinus bradycardia, and asthma.

#pharmacology

Reference:

MacCarthy EP, Bloomfield SS. Labetalol: a review of its pharmacology, pharmacokinetics, clinical uses and adverse effects. Pharmacotherapy. 1983 Jul-Aug;3(4):193-219. doi: 10.1002/j.1875-9114.1983.tb03252.x. PMID: 6310529.

Ca in dig toxicity

Q: Calcium can be administrated to hyperkalemic patients in digitalis (Dig) toxicity? 

A) Yes

B) No

Answer: A

Although common teaching at the bedside is to avoid calcium in hyperkalemia associated with dig. toxicity, the hyperkalemia should be treated with calcium for cardiac membrane stabilization in the same way as in any other patient or for similar EKG changes, i.e., loss of P waves and/or widening of the QRS complex. This is true even though hypercalcemia may potentiate the cardiotoxic effects of dig. Again, calcium is required to counter the membrane actions of hyperkalemia. 

Said that calcium should be given slowly in hyperkalemia associated with dig. toxicity. It can be given as 10-10-100 rule means 10 mL of 10 percent calcium gluconate in 100 mL of 5 percent dextrose in water (d-5 W) over 30 minutes. The formula can be extended as 10-10-100-5-30.

#electrolytes

#cardiology

#toxicity

References:

1. Mount DB. Disorders of potassium balance. In: Brenner and Rector's The Kidney, 11th ed, Yu A, Chertow G, Luyckx V, et al (Eds), W.B. Saunders & Company, Philadelphia 2020. p.537.

2. Levine M, Nikkanen H, Pallin DJ. The effects of intravenous calcium in patients with digoxin toxicity. J Emerg Med. 2011 Jan;40(1):41-6. doi: 10.1016/j.jemermed.2008.09.027. Epub 2009 Feb 6. PMID: 19201134.

Lactate in seizures

Q: What is the utility of lactate level in seizures?

Answer: To differentiate between syncope, a generalized seizure & non-epileptic events

Clinical events may appear as underlying epilepsy, such as unwitnessed transient loss of consciousness (LOC), coma, or psychogenic nonepileptic seizure. Lactic acid level remain high for about two hours after a generalized seizure. It can be a good marker for differentiation from other recent neurological events.

Other labs though non-specific, which may help to make a diagnosis are high creatine phosphokinase (CPK), cortisol, leucocytosis, LDH, and neuron-specific enolase.

#neurology

References:

1. Matz O, Heckelmann J, Zechbauer S, et al. Early postictal serum lactate concentrations are superior to serum creatine kinase concentrations in distinguishing generalized tonic-clonic seizures from syncopes. Intern Emerg Med 2018; 13:749.

2. Doğan EA, Ünal A, Ünal A, Erdoğan Ç. Clinical utility of serum lactate levels for differential diagnosis of generalized tonic-clonic seizures from psychogenic nonepileptic seizures and syncope. Epilepsy Behav 2017; 75:13.

3. Magnusson C, Herlitz J, Höglind R, et al. Prehospital lactate levels in blood as a seizure biomarker: A multi-center observational study. Epilepsia 2021; 62:408.

4. Willert C, Spitzer C, Kusserow S, Runge U. Serum neuron-specific enolase, prolactin, and creatine kinase after epileptic and psychogenic non-epileptic seizures. Acta Neurol Scand 2004; 109:318.

5. Petramfar P, Yaghoobi E, Nemati R, Asadi-Pooya AA. Serum creatine phosphokinase is helpful in distinguishing generalized tonic-clonic seizures from psychogenic nonepileptic seizures and vasovagal syncope. Epilepsy Behav 2009; 15:330.

acute colonic pseudo obstruction

Q: Give some of the side effects of using neostigmine in acute colonic pseudo-obstruction (Ogilvie's syndrome)?

Answer: Neostigmine is an acetylcholinesterase inhibitor used in acute colonic pseudo-obstruction (Ogilvie's syndrome) when conservative measures fail. Some of the side effects that need to be kept in mind are

• bradycardia
• hypotension
• asystole
• seizures
• restlessness
• tremor
• bronchoconstriction
• nausea
• vomiting
• salivation
• diarrhea
• sweating
• abdominal cramps

It should be used with caution in

• recent myocardial infarction
• acidosis
• asthma
• peptic ulcer disease
• concomitant use of beta-blockers

Side effects can be minimized by giving a lower dose or by coadministration of glycopyrrolate, an anticholinergic agent that has limited activity on the muscarinic receptors of the colon. Patient should be monitored closely, and atropine should be available at the bedside. Dose can be repeated if needed.

Neostigmine can also be given subcutaneously. It is also suggested to use polyethylene glycol after the resolution of colonic dilation to maintain its efficacy.

#GI

References:

Alavi K, Poylin V, Davids JS, et al. The American Society of Colon and Rectal Surgeons Clinical Practice Guidelines for the Management of Colonic Volvulus and Acute Colonic Pseudo-Obstruction. Dis Colon Rectum 2021; 64:1046.

Kram B, Greenland M, Grant M, et al. Efficacy and Safety of Subcutaneous Neostigmine for Ileus, Acute Colonic Pseudo-obstruction, or Refractory Constipation. Ann Pharmacother 2018; 52:505.

Sgouros SN, Vlachogiannakos J, Vassiliadis K, et al. Effect of polyethylene glycol electrolyte balanced solution on patients with acute colonic pseudo obstruction after resolution of colonic dilation: a prospective, randomised, placebo controlled trial. Gut 2006; 55:638.

Aztreonam cross-reactivity

Q: Aztreonam may have cross-reactivity with which of the cephalosporins? (select one)

A) ceftazidime

B) cefazolin

C) cefuroxime

D) cefepime

E) ceftriaxone

Answer: A

Interestingly Aztreonam, a monobactam that can be safely used in patients allergic to penicillin, may have cross-reactivity with ceftazidime. Most patients tolerate aztreonam with ceftazidime allergy, but concern stays for patients with previous immediate reactions to ceftazidime. The chance of developing a reaction due to cross-reactivity is about five percent. An alternate antibiotic should be used, or aztreonam skin test should be performed.

#pharmacology

References:

1. Pérez Pimiento A, Gómez Martínez M, Mínguez Mena A, et al. Aztreonam and ceftazidime: evidence of in vivo cross allergenicity. Allergy 1998; 53:624.

2. Iglesias Cadarso A, Sáez Jiménez SA, Vidal Pan C, Rodriguez Mosquera M. Aztreonam-induced anaphylaxis. Lancet 1990; 336:746.

3. van der Poorten MM, Van Gasse AL, Hagendorens MM, et al. Nonirritating skin test concentrations for ceftazidime and aztreonam in patients with a documented beta-lactam allergy. J Allergy Clin Immunol Pract 2021; 9:585.

Pentoxifylline Treatment in Severe Acute Pancreatitis

Q: Pentoxifylline may have a beneficial effect in acute pancreatitis?

A) Yes

B) No

Answer: A

Pentoxifylline is a nonselective phosphodiesterase inhibitor. There is a weak evidence that Pentoxifylline may have an adjuvant beneficial effect in acute pancreatitis, though objectively there was no improvement in inflammatory markers.

It may favor towards fewer ICU admissions and hospital length of stay (LOS). 

#GI

Reference:

Vege SS, Atwal T, Bi Y, et al. Pentoxifylline Treatment in Severe Acute Pancreatitis: A Pilot, Double-Blind, Placebo-Controlled, Randomized Trial. Gastroenterology 2015; 149:318.

festination

Q: What is festination in neurological exam?

Answer: Festination is an involuntary tendency to speed up when performing repetitive movements. It can be gait, handwriting and/or speech. It was originally described by Parkinson in 1817 in his original essay as festinating gait. It usually corelates with freezing of gait (FoG) and signifies late stages of Parkinson's disease.

#neurology

References:

1. Moreau C, Ozsancak C, Blatt JL, Derambure P, Destee A, Defebvre L. Oral festination in Parkinson's disease: biomechanical analysis and correlation with festination and freezing of gait. Mov Disord. 2007 Jul 30;22(10):1503-1506. doi: 10.1002/mds.21549. PMID: 17516477.

2. Imai H. [Festination and freezing]. Rinsho Shinkeigaku. 1993 Dec;33(12):1307-9. Japanese. PMID: 8174332.

3. Morris TR, Cho C, Dilda V, Shine JM, Naismith SL, Lewis SJ, Moore ST. A comparison of clinical and objective measures of freezing of gait in Parkinson's disease. Parkinsonism Relat Disord. 2012 Jun;18(5):572-7. doi: 10.1016/j.parkreldis.2012.03.001. Epub 2012 Mar 23. PMID: 22445248.

French Gauge diameter conversion in millimeters

Q: What is the French Gauge diameter conversion in millimeters (mm)?

Answer: The French gauge system is commonly used to measure the size of a catheter. It is often abbreviated in the USA as F.

A catheter of 1 French has a diameter of ⅓ mm 

For example Size 9 French converts to a diameter of 3 mm.

An increasing French size corresponds to a larger external diameter.

#procedures

Reference: 

Iserson KV. J.-F.-B. Charrière: the man behind the "French" gauge. J Emerg Med. 1987 Nov-Dec;5(6):545-8. doi: 10.1016/0736-4679(87)90218-6. PMID: 3323304.

IV Fe

Q: Intravenous(IV) Iron should be given with? (select one)

A) ideal body weight

B) actual body weight

Answer: B

There are 3 forms of IV Iron available in the USA. 

• Iron dextran 
• Iron sucrose 
• Sodium ferric gluconate

Iron dextran definitely requires a "test dose" in the presence of a physician with epinephrine at the bedside. About 1 out of 200 patients develop life-threatening anaphylaxis. In the remaining 2 forms, a test dose is advisable. Watch time after the 'test dose' is about one hour. IM or SQ administration of Iron is not standard of practice.

Also, the dose should be calculated irrespective of the form of iron used. Various formulae have been described (see references), but the most widely used is

Total amount of iron in mg = { 0.3 x abw (lbs) x 100 (14.8 - present Hgb)] / 14.8

• abw = actual body weight 
• 14.8 is constant as ideal Hb

Iron can also be given in acute blood loss situations. The formula is:

Total iron dose (in mg) = Blood loss (ml) x present Hematocrit.

The total Fe can be given as a single dose in .5 L NS over 6 hours or in divided doses over a few days.

#hematology

References: 

1. Girelli D, Ugolini S, Busti F, Marchi G, Castagna A. Modern iron replacement therapy: clinical and pathophysiological insights. Int J Hematol. 2018 Jan;107(1):16-30. doi: 10.1007/s12185-017-2373-3. Epub 2017 Dec 1. PMID: 29196967.

2. Schaefer B, Meindl E, Wagner S, Tilg H, Zoller H. Intravenous iron supplementation therapy. Mol Aspects Med. 2020 Oct;75:100862. doi: 10.1016/j.mam.2020.100862. Epub 2020 May 19. PMID: 32444112.

Nimodipine in SAH

Q: What is the optimum time of administration of Nimodipine in Subarachnoid Hemorrhage (SAH)?

Answer: At least within 96 hours to 21 days 

In subarachnoid hemorrhage (SAH), nimodipine's is used primarily in the prevention of cerebral vasospasm. It should be started as early as possible, at least within 4 days of a subarachnoid hemorrhage (SAH) and should be continued for 21 days. 

Nimodipine is a calcium channel blocker and has selectivity for cerebral vasculature.

Readers are recommended to browse reference # 2 below.

#neurology

#neurosurgery

References:

1. Sokolowski JD, Chen CJ, Soldozy S, Mastorakos P, Burke RM, Nguyen JM, Myers KM, Kalani MYS, Park MS. Nimodipine after aneurysmal subarachnoid hemorrhage: Fourteen-day course for patients that meet criteria for early hospital discharge. Clin Neurol Neurosurg. 2021 Jan;200:106299. doi: 10.1016/j.clineuro.2020.106299. Epub 2020 Oct 8. PMID: 33092929. 

2.  Samseethong T, Suansanae T, Veerasarn K, Liengudom A, Suthisisang C. Impact of Early Versus Late Intravenous Followed by Oral Nimodipine Treatment on the Occurrence of Delayed Cerebral Ischemia Among Patients With Aneurysm Subarachnoid Hemorrhage. Ann Pharmacother. 2018 Nov;52(11):1061-1069. doi: 10.1177/1060028018778751. Epub 2018 May 22. PMID: 29783859. https://pubmed.ncbi.nlm.nih.gov/29783859/

Hypertension in acute amphetamine intoxication

Q: The drug of choice to treat hypertension in acute amphetamine intoxication is? (select one)

A) benzodiazepine

B) Esmolol

C) Lopressor

D) Propranolol

Answer: A

Like cocaine intoxication, beta-blockers (BB) should be avoided in acute amphetamine intoxication (choices B, C, and D). The first line of treatment is benzodiazepines. If further help is needed, non-BB should be used, such as nitroglycerin or nitroprusside. 

If no choice is left and BB is absolutely needed, it would be prudent to add an alpha antagonist.

#hemodynamic

#toxicology

#pharmacology

Reference: 

1. White SR. Amphetamine toxicity. Semin Respir Crit Care Med. 2002 Feb;23(1):27-36. doi: 10.1055/s-2002-20586. PMID: 16088595.

2. Ferdinand KC. Substance Abuse and Hypertension. J Clin Hypertens (Greenwich). 2000 Jan;2(1):37-40. PMID: 11416624.

LR

Q: Why "bicarb drip" should not be prepared in Lactated Ringer's (LR) solution?

Answer: LR contains calcium and will bind bicarb to produce calcium carbonate (chalk).

One liter of Lactated Ringer's Solution contains:

• 130 mEq/L of Na+ (but total cations of 137 mEq/L , so is still isotonic).
• 109 mEq/L of Cl−
• 28 mEq/L of lactate
• 4 mEq/L of potassium
• 3 mEq/L of calcium

#electrolytes

Reference:

Singh S, Kerndt CC, Davis D. Ringer's Lactate. 2022 Aug 22. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2022 Jan–. PMID: 29763209.

A simple mnemonic to diagnose Iron-deficiency anemia

A simple mnemonic to diagnose Iron-deficiency anemia

There are six lab tests to confirm Fe-deficiency anemia.

Mnemonic is

- Decrease FHM

- Increase TTR

F = Ferritin
H = Hemoglobin
M= MCV (Mean Copuscular Volume)

T = TIBC (Total Iron Binding Capacity)

T = Transferrin

R = RDW (red cell distribution width)

#hematology

Reference:

Kumar A, Sharma E, Marley A, Samaan MA, Brookes MJ. Iron deficiency anaemia: pathophysiology, assessment, practical management. BMJ Open Gastroenterol. 2022 Jan;9(1):e000759. doi: 10.1136/bmjgast-2021-000759. PMID: 34996762; PMCID: PMC8744124.

pseudo-pulmonary embolus syndrome

Q: What is pseudo-pulmonary embolus syndrome?

Answer: Shortly after an intravenous heparin bolus, the clinical scenario of collapse is called 'pseudo pulmonary embolus.' This is not due to a major pulmonary embolus but is thought to be due to an endothelial injury, with the sudden augmented release of IL-6, von Willebrand factor, and other adhesion molecules, resulting in an acute adult-type respiratory distress syndrome as result of a sudden vascular leak with hypoxia and hypotension.

It is observed in patients with underlying heparin-induced thrombocytopenia (HIT).

#pulmonary

#vascular

#hemodynamic

References:

1. Hartman V, Malbrain M, Daelemans R, Meersman P, Zachée P. Pseudo-pulmonary embolism as a sign of acute heparin-induced thrombocytopenia in hemodialysis patients: safety of resuming heparin after disappearance of HIT antibodies. Nephron Clin Pract. 2006;104(4):c143-8. doi: 10.1159/000094959. Epub 2006 Aug 10. PMID: 16902310.

2. Salomon O, Leshem Y, Gluck I, Grossman E, Apter S, Konen E. Pseudo pulmonary embolism in cancer patients: a new clinical syndrome. Blood Coagul Fibrinolysis. 2014 Dec;25(8):871-5. doi: 10.1097/MBC.0000000000000174. PMID: 25022841.

3. Popov D, Zarrabi MH, Foda H, Graber M. Pseudopulmonary embolism: acute respiratory distress in the syndrome of heparin-induced thrombocytopenia. Am J Kidney Dis. 1997 Mar;29(3):449-52. doi: 10.1016/s0272-6386(97)90208-0. PMID: 9041223.

End of life care - upper airway secretions

Q: 48 years old male in comfort/palliative care in ICU start having a lot of upper respiratory noises from secretions. The family is extremely distressed and asked for some symptomatic relief?

Answer: Noises caused by upper airway secretions are heard in half of dying patients as they cannot swallow or clear them. The presence of respiratory secretions is a strong predictor of death within 48 hours. This could be very discomforting to the family and the patient. Different options to consider includes;

1. Glycopyrrolate: 0.2 mg as a single dose SC. In case of good response, it may be continued with the dose of 0.2 mg q4h prn SC. It can be given as IV also with caution.

(Glycopyrrolate is an excellent choice also in other ICU patients who continue to display high respiratory secretions, particularly vented patients)

2. Atropine: 0.6-0.8 mg SC. If effective, continue using q4h prn.

3. Hyoscine butylbromide: 20 mg as a single dose SC. If effective, continue using 20 mg q4h SC.

Further readings:

Bennett M, Lucas V, Brennan M, Hughes A, O’Donnell V, Wee B. Association for Palliative Medicine’s Science Committee. Using antimuscarinic drugs in the management of death rattle: evidence-based guidelines for palliative care. Palliat Med 2002;16(5):369-74. 

Downing GM, Wainwright W, editors. Medical care of the dying. 4th ed. Victoria (BC): Victoria Hospice Society; 2006. p. 363-393.

Ogilvy and Carter grading

Q: Ogilvy and Carter grading system is used for which disease?

Answer: Subarachnoid Hemorrhage (SAH)

Ogilvy and Carter's grading for SAH is to predict outcomes for surgical management of SAH due to ruptured aneurysm. It is graded from 0 to 5 points, with one point each for following component:

• age>50
• Hunt and Hess grade 4-5 
• Fisher grade score 3-4
• aneurysm size>10 mm
• additional point for a giant posterior circulation aneurysm (≥25 mm)

Study is validated, showing following outcomes.

Grade 0-2 = 78% good outcomes

Grade 3 = 67% good outcomes

Grade 4 = 25%  good outcomes

Grade 5 = not a surgical candidate

#neurology

#neurosurgery

Reference:

Ogilvy CS, Carter BS. A proposed comprehensive grading system to predict outcome for surgical management of intracranial aneurysms. Neurosurgery 1998; 42:959.

Hemodialysis-associated ascites

Q: Hemodialysis-associated ascites usually has a high protein content.

A) True

B) False

Answer: A

 Hemodialysis-associated ascites is also known as nephrogenic ascites. One unique feature of hemodialysis-associated ascites is a high protein content, i.e.,3-6 g/dL, but simultaneously low serum ascites albumin gradient (SAAG). Despite its high protein content, it is usually clear in appearance. 

Hemodialysis-associated ascites is distinct from other causes of ascites and is a diagnosis of exclusion. Pathophysiology is not properly known and is also called idiopathic dialysis ascites. It is assumed that cause is chronic hepatic congestion, changes in the peritoneal membrane permeability, and impaired lymphatic peritoneal resorption. As expected, it is more common in patients who are on chronic peritoneal dialysis.

#hepatology

#nephrology

#GI

References:

1. Hammond TC, Takiyyuddin MA. Nephrogenic ascites: a poorly understood syndrome. J Am Soc Nephrol 1994; 5:1173.

2. Holm A, Rutsky EA, Aldrete JS. Short- and long-term effectiveness, morbidity, and mortality of peritoneovenous shunt inserted to treat massive refractory ascites of nephrogenic origin analysis of 14 cases. Am Surg 1989; 55:645.

3. Feingold LN, Gutman RA, Walsh FX, Gunnells JC. Control of cachexia and ascites in hemodialysis patients by binephrectomy. Arch Intern Med 1974; 134:989.

4. Melero M, Rodriguez M, Araque A, et al. Idiopathic dialysis ascites in the nineties: resolution after renal transplantation. Am J Kidney Dis 1995; 26:668.

Fecal loading in the cecum

Q: KUB film showed Fecal loading in the cecum. What is your diagnosis?

Answer: Acute Appendicitis

The image of fecal loading in the cecum presented a sensitivity of 97% for acute appendicitis. This sign is higher than other signs included in the clinical, laboratory, and even imaging workups for patients with acute appendicitis.

Reference:

Radiographic image of fecal loading in the cecum as a diagnostic sign of acute appendicitis - Radiol Bras vol.40 no.4 São Paulo July/Aug. 2007 

Link: https://www.scielo.br/j/rb/a/mhthXJPmsTCsjsJL9JHN5Vv/?lang=en

Mannitol induced AKI

Q: Mannitol-induced acute kidney injury tends to be?

A) reversible

B) irreversible

Answer: A

Care should be taken when writing repeated doses of mannitol. In a normal healthy patients AKI does not develop up to 200-300 grams of mannitol per day. This ballpark dose depends largely on underlying comorbidities and baseline kidney function, including diabetes, CHF, high APACHE or NIHSS score, other diuretic use and total cumulative dose of mannitol. 

Clinically, 6-11 percent of patients treated with mannitol are said to develop AKI. Although the mannitol induced AKI is slow to recover, the early institution of hemodialysis (HD) reverses the course quickly by removing cumulated mannitol within one or two sessions.

#pharmacology

#toxicology

References:

1. Gadallah MF, Lynn M, Work J. Case report: mannitol nephrotoxicity syndrome: role of hemodialysis and postulate of mechanisms. Am J Med Sci 1995; 309:219.

2. Pérez-Pérez AJ, Pazos B, Sobrado J, et al. Acute renal failure following massive mannitol infusion. Am J Nephrol 2002; 22:573.

Better OS, Rubinstein I, Winaver JM, Knochel JP. Mannitol therapy revisited (1940-1997). Kidney Int 1997; 52:886.

3. Lin SY, Tang SC, Tsai LK, et al. Incidence and Risk Factors for Acute Kidney Injury Following Mannitol Infusion in Patients With Acute Stroke: A Retrospective Cohort Study. Medicine (Baltimore) 2015; 94:e2032.

4. Kim MY, Park JH, Kang NR, et al. Increased risk of acute kidney injury associated with higher infusion rate of mannitol in patients with intracranial hemorrhage. J Neurosurg 2014; 120:1340.

treatment of D-Lactic acidosis

Q: What is the treatment of D-Lactic acidosis?

Answer: D-lactate is a byproduct of bacterial metabolism and may accumulate in patients with short-gut syndrome. It is a common finding in patients with history of gastric bypass or small-bowel resection. Bacteria metabolize glucose and carbohydrate to D-lactic acid, which is then systemically absorbed. D-lactate is slowly metabolized by human subjects, and accumulate in patients with short guts. It is clinically a benign condition.

Treatment consists of

• restriction of simple sugars,
• hydration,
• bicarbonate administration if severe acidosis

Use of metronidazole or rifaximin has been described but it is controversial as antibiotics can make the syndrome worse by permitting overgrowth of lactobacilli.

References:

1. Uribarri J, Oh MS, Carroll HJ: D-Lactic acidosis. Medicine 77:73 -82, 1998

2. Coronado BE, Opal SM, Yoburn DC: Antibiotic-induced D-lactic acidosis. Ann Intern Med 122:839 -842, 1995

Wandering spleen

Q: You have been called to ER to evaluate a 38 years old female  with fever, abdominal pain, vomiting, dehydration and hypotension. Physical exam shows pain in left lower quadrant with palpable mass. Patient feels relief of pain as you move mass towards left upper quadrant! What you should wonder?

Answer: Wandering spleen

In wandering spleen, the spleen can be found in any part of the abdomen or pelvis because of the length of its pedicle. In acquired form it is due to laxity of ligaments particularly due to multiple pregnancies in child bearing age women.

The abnormally fixed spleen can twist on its vascular pedicle, creating ischemia that may progress to infarction and may presents as an acute abdomen.

It may presents as a triad of

• a firm ovoid mass with a notched edge
• painful movement of the mass except when the mass is moved toward the left upper quadrant 
• resonance to percussion in the left upper quadrant

Treatment is operative.

#GI

#surgical-critical-care

References:

1. Reisner DC, Burgan CM. Wandering Spleen: An Overview. Curr Probl Diagn Radiol. 2018 Jan-Feb;47(1):68-70. doi: 10.1067/j.cpradiol.2017.02.007. Epub 2017 Feb 16. PMID: 28385371.

2. Soleimani M, Mehrabi A, Kashfi A, Fonouni H, Büchler MW, Kraus TW. Surgical treatment of patients with wandering spleen: report of six cases with a review of the literature. Surg Today. 2007;37(3):261-9. doi: 10.1007/s00595-006-3389-0. Epub 2007 Mar 9. PMID: 17342372.

3 "Pseudos" of Thrombocytosis

Q: Name (at least) 3 "Pseudos" of Thrombocytosis (high platelet counts)?

Answer: Browsing platelet count is a good habit before interpreting other labs. High platelet count, i.e., thrombocytosis may cause

• Pseudo-hyperkalemia 
• Pseudo-hyperphosphatemia 
• Pseudo-hyper-acid phosphatase 
• Pseudo-hypoxemia (even on ABG) 

#hematology

#lab-medicine

References: 

1. Pseudo-hyperkalemia and thrombocytosis - Ann Biol Clin (Paris). 2003 Nov-Dec;61(6):696-8

2. The effect of thrombocytosis on serum potassium and phosphorus concentrations - The American journal of the medical sciences 1994, vol. 307, n 4, pp. 255-258 (19 ref.) - http://cat.inist.fr/?aModele=afficheN&cpsidt=4062835

3. Platelet-derived acid phosphatase isoenzyme in the serum in thrombocythemia - Am J Clin Pathol.1977 Feb;67(2):177-9

4. Platelet larceny: spurious hypoxaemia due to extreme thrombocytosis - Eur Respir J 2008; 31:469-472

Behavioral Variant Frontotemporal Dementia

Q: 67 years old male is admitted to ICU for a suicidal watch. Patient is lately noted to have increased compulsive behavior of hanging out on his balcony. He claims he read in a book that such acts is needed to enhance spirituality. The family also reported disinhibition with public urination, loss of empathy, and hyperorality. These behaviors are inclined to represent which dementia?

Answer: Behavioral variant of frontotemporal dementia (bvFTD)

Behavioral variant FTD (bvFTD) is the most common type of FTD. Patients are frequently referred to or misdiagnosed as psychiatric patients. The four major hallmarks of such dementia are

• public disinhibition 
• apathy and loss of empathy with loss of motivation and interest in social relationships
• hyperorality with a tendency to attempt to consume inedible objects
• compulsive behaviors like our patient in this question

#neurology

#psychiatry

References:

1. Peet BT, Castro-Suarez S, Miller BL. The Neuropsychiatric Features of Behavioral Variant Frontotemporal Dementia. Adv Exp Med Biol. 2021;1281:17-31. doi: 10.1007/978-3-030-51140-1_2. PMID: 33433866.

2. Boeve BF. Behavioral Variant Frontotemporal Dementia. Continuum (Minneap Minn). 2022 Jun 1;28(3):702-725. doi: 10.1212/CON.0000000000001105. PMID: 35678399; PMCID: PMC9578563.