Thursday, April 30, 2020

Decrease resp acidosis during Trachesostomy

Q: Describe one technique during percutaneous tracheostomy to decrease the incidence of respiratory acidosis due to a delay in mechanical ventilation?



Answer: Bridge with pediatric ETT

In high-risk patients with little reserve or with relatively high ventilator settings, respiratory acidosis may occur during percutaneous tracheostomy. This is due to a delay between discontinuation from mechanical ventilator and insertion of a tracheostomy tube. This complication can be monitored by the use of end-tidal carbon dioxide (ET-CO2). This complication can be avoided by the ETT exchange with pediatric endotracheal tube (ETT) before initiating the procedure. Pedatric ETT can stay in trachea till the tracheostomy is finished and confirmed.


#procedures



Reference:


Ferraro F, Capasso A, Troise E, et al. Assessment of ventilation during the performance of elective endoscopic-guided percutaneous tracheostomy: clinical evaluation of a new method. Chest 2004; 126:159.

Wednesday, April 29, 2020

Diuresis in acute cardiogenic pulmonary edema

Q: A response to diuresis is one way to confirm the diagnosis of acute cardiogenic pulmonary edema?

A) True
B) False


Answer: A

Physical exam stays a primary way to diagnose acute cardiogenic pulmonary edema. It includes S3 or S4 gallop on cardiac auscultation, elevated jugular venous pressure, or leg edema. Diagnosis can be supplemented by CXR showing pulmonary venous congestion, Kerley B lines, cardiomegaly, and pleural effusions. Another way to confirm (and treat) acute cardiogenic pulmonary edema in non-renal failure patients is to give a trial of diuresis.


#cardiology
#pulmonary


Reference:


Purvey M, Allen G. Managing acute pulmonary oedema. Aust Prescr. 2017;40(2):59–63. doi:10.18773/austprescr.2017.012

Tuesday, April 28, 2020

HEART score

Q: What is the Heart score?

Answer: 

 HEART score is a clinical decision tool along with clinical judgment to identify risk of Acute Coronary Syndrome (ACS) in undifferentiated chest pain patients.

H = History

E = Electrocardiogram (EKG/ECG)
A= Age
R = Risk factors
T = Troponin


  • 0-3: low risk, potential candidate for early discharge.
  • 4-6: moderate risk, potential candidate for observation & further evaluation.
  • 7-10: high risk, candidate for urgent or emergent intervention.
Calculator can be found at various online search engines or in the article link given below in the reference section.


#cardiology


Reference:

Brady W, de Souza K. The HEART score: A guide to its application in the emergency department. Turk J Emerg Med. 2018;18(2):47–51. Published 2018 Jun 14. doi:10.1016/j.tjem.2018.04.004

 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6005932/


Monday, April 27, 2020

Prone in ARDS

Q: According to famous PROSEVA (Prone Positioning in Severe Acute Respiratory Distress Syndrome) trial, early proning is recommended. What was the cutoff time used in trial?



Answer: 33 hours

PROSEVA trial despite its various limitations is considered a landmark work in ARDS. It showed that prone positioning can be beneficial to patients with severe ARDS who are on mechanical ventilator, and already getting treated with low tidal volume protocol.  Benefit of proning is best achieved if done within 33 hours of intubation, and be done for at least 16-18 hours per day. It showed overall reduction in 28-days mortality between intervention and controlled arm (16 versus 32.8 percent).


#pulmonary



Reference:


Guérin C, Reignier J, Richard JC, et al. Prone positioning in severe acute respiratory distress syndrome. N Engl J Med 2013; 368:2159.

Sunday, April 26, 2020

Dexmedetomidine Clonidine

Q: Infusion of dexmedetomidine in ICU patients can be transitioned to which oral medicine? 



Answer: Clonidine

Although not routinely utilized but dexmedetomidine can be transitioned to oral clonidine. It is safe as well as cost-effective. This is due to the fact of their similar mechanism of action via centrally acting alpha-2-agonist effect. Dexmedetomidine can be gradually titrated down with escalation of clonidine dosage up to 0.2 to 0.5 mg every six hours.

#pharmacology
#sedation


Reference:


Gagnon DJ, Riker RR, Glisic EK, et al. Transition from dexmedetomidine to enteral clonidine for ICU sedation: an observational pilot study. Pharmacotherapy 2015; 35:251.

Saturday, April 25, 2020

cuff leak test in COVID-19

Q: Routine cuff leak should be performed in all COVID-19 patients on extubation?

A) True
B) False


Answer: B

Cuff leak test may have a potential of aerosolization. It should be avoided routinely in COVID-19 patients unless clinically indicated. It can be done judiciously in patients with suspicion of upper airway edema, prolonged intubation of more than a week, age more than 80 years, large endotracheal tube (ETT), and known trauma during intubation. In an ideal situation, if a clinician feels an extreme necessity of doing a cuff leak test prior to extubation, it should be performed in an airborne isolation room. A successful cuff leak test consists of volumes of greater than 110 mL or greater than 24 percent of the delivered tidal volume (TV).


See open-access article in the reference section.


#pulmonary

#COVID-19


Reference:




T. M. Cook, K. El‐Boghdadly, B. McGuire, A. F. McNarry, A. Patel, A. Higgs. Consensus guidelines for managing the airway in patients with COVID‐19. Guidelines from the Difficult Airway Society, the Association of Anaesthetists the Intensive Care Society, the Faculty of Intensive Care Medicine and the Royal College of Anaesthetists. First published:27 March 2020 

https://doi.org/10.1111/anae.15054. Weblink: https://onlinelibrary.wiley.com/doi/10.1111/anae.15054

Friday, April 24, 2020

COVID-19 and C-section

Q: 28-year-old female at 36 weeks of pregnancy is admitted to ICU with respiratory failure due to COVID-19. Obstetric service decided to perform a cesarean delivery. What is the risk of vertical transmission to baby?

A) High
B) Low


Answer; B

The objective of the above question is to highlight three cardinal points from the recent National Institute of Health (NIH) guidelines (links are given in the reference section) for pregnant patients diagnosed with COVID.


1.  Mere a diagnosis of COVID-19 is not an indication for early delivery. Individualized delivery planning is recommended for each patient depending on fetal and uterine contraction monitoring and obstetric indication. 


2. It is reasonable to attempt to postpone delivery (if no other medical indications arise) until a negative test result is obtained or quarantine restrictions are lifted in an attempt to avoid virus transmission to the neonate. 

 3. Till to date, there appears to be no risk of vertical transmission of SARS-CoV-2 via the transplacental route.


#Ob-Gyn
#COVID-19


References:


1. COVID-19 Treatment Guidelines. Special Considerations in Pregnancy and Post-Delivery. NIH. 2020. Weblink: https://covid19treatmentguidelines.nih.gov/overview/pregnancy-and-post-delivery/ Last accessed April 22, 2020 


2. The American College of Obstetricians and Gynecologists. COVID-19 frequently asked questions for obstetricians-gynecologists, obstetrics. 2020. Available at: https://www.acog.org/clinical-information/physician-faqs/covid-19-faqs-for-ob-gyns-obstetrics. Accessed April 22, 2020.

Thursday, April 23, 2020

Melatonin for procedure

Q: What is the role of Melatonin in reducing procedural anxiety?


Answer: 

Benzodiazepines are the first line of pre-medications for the treatment of procedural anxiety. If a patient is not a candidate for benzodiazepines, 3-5 mg of sublingual melatonin can be given with a good comparable effect. The dose can be repeated in 30 to 60 minutes if needed. 

Sublingual melatonin has an anxiolytic and sedative effect. Its use is limited by less psychomotor impairment and quicker recovery time than midazolam, the most widely used pre-procedural drug.


#surgical-critical-care

#pharmacology


References:


1. Naguib M, Samarkandi AH. The comparative dose-response effects of melatonin and midazolam for premedication of adult patients: a double-blinded, placebo-controlled study. Anesth Analg 2000; 91:473. 


 2. Acil M, Basgul E, Celiker V, et al. Perioperative effects of melatonin and midazolam premedication on sedation, orientation, anxiety scores and psychomotor performance. Eur J Anaesthesiol 2004; 21:553. 


3. Ionescu D, BĂŁdescu C, Ilie A, et al. Melatonin as premedication for laparoscopic cholecystectomy: a double-blind, placebo-controlled study. South Afr J Anaesth Analg 2008; 14:8.

Wednesday, April 22, 2020

ivermectin

Q: 32-year-old male who recently traveled from Africa after his global health fellowship is admitted to ICU with pulmonary symptoms. Patient gets diagnosed with Strongloidosis and was prescribed ivermectin by ID service. Patient was unable to tolerate ivermectin by central route due to high nasogastric output. What other route is preferred?


Answer: Subcutaneous

Enteral route is preferred for ivermectin but if not feasible it can be given as subcutaneously. Although rectal route is also suggested, it may not achieve an effective serum level. 


#infectious-diseases

#pulmonary


References:


1. Barrett J, Broderick C, Soulsby H, et al. Subcutaneous ivermectin use in the treatment of severe Strongyloides stercoralis infection: two case reports and a discussion of the literature. J Antimicrob Chemother 2016; 71:220. 


2. Bogoch II, Khan K, Abrams H, et al. Failure of ivermectin per rectum to achieve clinically meaningful serum levels in two cases of Strongyloides hyperinfection. Am J Trop Med Hyg 2015; 93:94.

Tuesday, April 21, 2020

hemoptysis - physical exam

Q: In a patient with hemoptysis, auscultation of chest should be performed as it may easily determine the side of bleeding lung? 

A) True
B) False


Answer: B

 Although physical exam universally remains an integral part of any patient's management, it can not be solely relied upon in hemoptysis. Additional investigations should be performed including chest-x-ray, CT scan or bronchoscopy. Protection of the airway remains the first priority.


Determination of bleeding lung helps to protect the preserved (good) lung. Patient should be placed in the dependent position of the suspected (bleeding) lung. Putting bleeding lung at a dependent position protects the non-bleeding lung just by a gravitational pool of blood. Once the bleeding site is confirmed, one-lung ventilation should be considered. Unfortunately, just relying on physical exam and auscultation of lung does not help since an unknown amount of blood may already have been spilled into the good lung.


#physical-exam

#pulmonary


References:


1. Hirshberg B, Biran I, Glazer M, Kramer MR. Hemoptysis: etiology, evaluation, and outcome in a tertiary referral hospital. Chest 1997; 112:440. 


2. Knott-Craig CJ, Oostuizen JG, Rossouw G, et al. Management and prognosis of massive hemoptysis. Recent experience with 120 patients. J Thorac Cardiovasc Surg 1993; 105:394.

Monday, April 20, 2020

3 test rule

Q: Three-test rule is used to diagnose which disease?

Answer: Pleural effusion

Although Light's criteria is considered a standard to distinguish transudative and exudative pleural effusion. There are equally reliable and easy to apply tests available like Two-test and three test rules.  The fluid is most probably exudative if:


 Two-test rule 

  •  Pleural fluid cholesterol > 45 mg/dL 
  •  Pleural fluid LDH > 0.45 times the upper limit of the normal serum LDH 
Three-test rule 
  •  Pleural fluid protein > 2.9 g/dL 
  •  Pleural fluid cholesterol > 45 mg/dL 
  •  Pleural fluid LDH > 0.45 times the upper limit of the normal serum LDH

#pulmonary


References:

1. Paramothayan NS, Barron J. New criteria for the differentiation between transudates and exudates. J Clin Pathol. 2002;55(1):69–71. doi:10.1136/jcp.55.1.69

2. Na MJ. Diagnostic tools of pleural effusion. Tuberc Respir Dis (Seoul). 2014;76(5):199–210. doi:10.4046/trd.2014.76.5.199


3. Romero S, Candela A, Martin C, et al. Evaluation of different criteria for the separation of pleural transudates from exudates. Chest 1993;104:399–404. 


4. Burgess LJ, Maritz FJ, Taljaard JJF. Comparative analysis of the biochemical parameters used to distinguish between pleural transudates and exudates. Chest 1995;107:1604–9. 


5. Gonlugur U, Gonlugur TE. The distinction between transudates and exudates. J Biomed Sci 2005; 12:985. 


6. Kummerfeldt CE, Chiuzan CC, Huggins JT, et al. Improving the predictive accuracy of identifying exudative effusions. Chest 2014; 145:586.

Sunday, April 19, 2020

Chlorhexidine and VAP

Q: Oral decontamination with Chlorhexidine should be done on all intubated patients in as there is strong evidence that it decreases the incidence of Ventilator-Associated Pneumonia (VAP)?

A) True
B) False


Answer: B

Although oral decontamination with chlorhexidine is a common practice in ICUs to decrease the incidence of VAP, studies have failed to show strong evidence for it. In fact, the combined European and Latin American guidelines do not endorse it as there are some indications that it might even increase mortality. There is a suspicion that aspiration of chlorhexidine may lead to acute respiratory distress syndrome (ARDS).


#pulmonary



References:


1. Torres A, Niederman MS, Chastre J, et al. International ERS/ESICM/ESCMID/ALAT guidelines for the management of hospital-acquired pneumonia and ventilator-associated pneumonia: Guidelines for the management of hospital-acquired pneumonia (HAP)/ventilator-associated pneumonia (VAP) of the European Respiratory Society (ERS), European Society of Intensive Care Medicine (ESICM), European Society of Clinical Microbiology and Infectious Diseases (ESCMID) and AsociaciĂłn Latinoamericana del TĂłrax (ALAT). Eur Respir J 2017; 50. 


2.  Klompas M, Li L, Kleinman K, et al. Associations Between Ventilator Bundle Components and Outcomes. JAMA Intern Med 2016; 176:1277. 


3.  Price R, MacLennan G, Glen J, SuDDICU Collaboration. Selective digestive or oropharyngeal decontamination and topical oropharyngeal chlorhexidine for prevention of death in general intensive care: systematic review and network meta-analysis. BMJ 2014; 348:g2197.

Saturday, April 18, 2020

antibiotics and myasthenia crisis

Q: Which of the following antibiotics can make myasthenia crisis worse?

A) fluoroquinolones 
B) cephalosporins


Answer: A

ICU physicians need to be vigilant about reflexly using some medications while dealing with myasthenia crisis patients. There are many surgical, medical, physiological and pharmacological etiologies to precipitate or make myasthenic crisis worse. It includes thymectomy itself which is considered a surgical cure for myasthenia gravis (MG). All such patients should be watched post-operatively in ICU. Other precipitating factors are pregnancy, childbirth, or when immunosuppressive drugs are on taper. 


 When it comes to drugs aminoglycosides, fluoroquinolones, erythromycin, azithromycin, beta-blockers, procainamide, quinidine, and magnesium have pronounced effects. Patients with a history of MG should not be on automated ICU electrolytes protocol to avoid magnesium infusion bt accident.


#neurology

#pharmacology
#OB-GYN


References:


1. Gummi RR, Kukulka NA, Deroche CB, Govindarajan R. Factors associated with acute exacerbations of myasthenia gravis. Muscle Nerve 2019; 60:693. 


2. French DM, Bridges EP, Hoskins MC, et al. Myasthenic Crisis In Pregnancy. Clin Pract Cases Emerg Med 2017; 1:291.

Friday, April 17, 2020

IVIG in GBS

Q: What is the multi-facets mechanism of action of intravenous immunoglobulin (IVIG) in Guillain-BarrĂ© syndrome(GBS)? 

 Answer: The precise mechanism of  IVIG in GBS is not entirely clear but probabilities have been described with following actions. The objective of the above question is to emphasize the multi-facet mechanism of action of IVIG instead of using umbrella term of antagonizing the hostile molecules.

1. provide anti-idiotypic antibodies

2. modulate expression and function of Fc receptors
3. interfere with the activation of complement and production of cytokines, and 
4. interfere with the activation and effector functions of T and B cells

#neurology




References: 


 1. Buchwald B, Ahangari R, Weishaupt A, Toyka KV. Intravenous immunoglobulins neutralize blocking antibodies in Guillain-BarrĂ© syndrome. Ann Neurol 2002; 51:673. 


 2. Dalakas MC. The use of intravenous immunoglobulin in the treatment of autoimmune neuromuscular diseases: evidence-based indications and safety profile. Pharmacol Ther 2004; 102:177.

Thursday, April 16, 2020

First trimester COVID

Q: How simple use of acetaminophen (Tylenol) can help in COVID-19 patients in first trimester of pregnancy?

Answer: The biggest risk during the first trimester in COVID patients is from hyperthermia/fever, one of the cardinal symptoms of COVID-19. The first trimester is crucial for organogenesis. Increase core maternal temperature may lead to increased congenital anomalies, particularly neural tube defects, congenital heart diseases, and cleft palates. It also increases the chances of miscarriage. Acetaminophen is considered safe during first trimester of pregnancy. It can be the most cost-effective measure.

#Infectious-diseases

#Ob-Gyn



References:


1. Edwards MJ. Review: Hyperthermia and fever during pregnancy. Birth Defects Res A Clin Mol Teratol 2006; 76:507.  


2. Dreier JW, Andersen AM, Berg-Beckhoff G. Systematic review and meta-analyses: fever in pregnancy and health impacts in the offspring. Pediatrics 2014; 133:e674. 

3. Graham JM Jr, Edwards MJ, Edwards MJ. Teratogen update: gestational effects of maternal hyperthermia due to febrile illnesses and resultant patterns of defects in humans. Teratology 1998; 58:209. 

4.  Waller DK, Hashmi SS, Hoyt AT, et al. Maternal report of fever from cold or flu during early pregnancy and the risk for noncardiac birth defects, National Birth Defects Prevention Study, 1997-2011. Birth Defects Res 2018; 110:342. 

5.  Feldkamp ML, Meyer RE, Krikov S, Botto LD. Acetaminophen use in pregnancy and risk of birth defects: findings from the National Birth Defects Prevention Study. Obstet Gynecol 2010; 115:109.

Wednesday, April 15, 2020

Remdisivir and renal function

Q: Remdesivir has shown some promise in COVID-19. How its role is limited by renal impairment?


Answer: Remdesivir is one of the few drugs which have shown some promise in the treatment of COVId-19. Its use is limited by the liver and renal insufficiencies.

Liver toxicity is a direct effect but the renal effect is due to the vehicle in which it is delivered parenterally. Remdisivir needs to be prepared in a cyclodextrin vehicle, which may get accumulated at a toxic level in patients with compromised kidney function. It should be given with extreme caution to patients with creatinine clearance less than 50 mL/min.


#infectious-diseases

#COVID-19


Reference: 


Grein J, Ohmagari N, Shin D,et.al.   Compassionate Use of Remdesivir for Patients with Severe Covid-19. N Engl J Med. 2020 Apr 10. doi: 10.1056/NEJMoa2007016.

Tuesday, April 14, 2020

Acute exacerbation of bronchiectasis

Q: Acute exacerbation of bronchiectasis is usually accompanied by all of the following except?

A) increased, darker and viscous sputum 
B) shortness of breath
C) pleuritic chest pain
D) possible hemoptysis. 
E) high grade fever and chills 


Answer: E

Acute exacerbation of bronchiectasis is accompanied by a high burden of bacterial pathogens associated with high inflammation. This results in production of sputum, which is more viscous and darker in color. Interestingly high grade fever and chills are generally absent. Patient may have lassitude, shortness of breath, pleuritic chest pain, or possible hemoptysis.


#pulmonary



Reference:


1. Hill AT, Haworth CS, Aliberti S, et al. Pulmonary exacerbation in adults with bronchiectasis: a consensus definition for clinical research. Eur Respir J 2017; 49.

Monday, April 13, 2020

Statins and COVID

Q: How statins can have some indirect benefit in COVID-19 patients?



Answer: Statins can have a beneficial effect in COVID-19 patients via two mechanisms

First, a large proportion of COVID-19 hospitalized patients have underlying cardiac history and statins may cont to play a beneficial role.


Second, data from previous epidemics of SARS-CoV and MERS-CoV shows the dysregulation of MYD88 pathway and association with poor outcome. Statins stabilizes and inhibits MYD88 levels. Similar could be true for COVID-19. Stabalization of MYD88 pathway may help in decrease inflammation during cytokine release storm of COVID-19.


#infectious-diseases 



References:


Yuan S. Statins May Decrease the Fatality Rate of Middle East Respiratory Syndrome Infection. mBio 2015; 6:e01120.

Sunday, April 12, 2020

Neutropenic fever

Q: What is the official definition of neutropenic fever?


Answer: Per Infectious Diseases Society of America (IDSA) fever in neutropenic patients is defined as a single oral temperature of ≥38.3°C (101°F) or a temperature of ≥38.0°C (100.4°F) sustained over a one-hour period.

The objective of the above question is to enhance the learning that even in the normal individuals' range of normal body temperature can have a wide range with an upper limit of 38°C (100.8°F). The range can be anywhere from 35.6°C (96.0°F) to 38.2°C (100.8°F).


#infectious-diseases



References:


1. Freifeld AG, Bow EJ, Sepkowitz KA, et al. Clinical practice guideline for the use of antimicrobial agents in neutropenic patients with cancer: 2010 update by the infectious diseases society of America. Clin Infect Dis 2011; 52:e56.


2. Mackowiak PA, Wasserman SS, Levine MM. A critical appraisal of 98.6 degrees F, the upper limit of the normal body temperature, and other legacies of Carl Reinhold August Wunderlich. JAMA 1992; 268:1578.

Saturday, April 11, 2020

Phenotypes in COVID


Phenotypes in COVID-19 determines the ventilator management



#pulmonary

Friday, April 10, 2020

Liquid plasma

Q: What is Liquid Plasma? 

Answer: Liquid Plasma is plasma that has never been frozen. 

Liquid Plasma is separated and infused no later than five days after the expiration date of the whole blood from which it is prepared. It is stored at 1 to 6°C. 


Clinical use: It can be useful in early trauma management. There is weak evidence that "endotheliopathy" associated with severe trauma responds better to plasma that has never been frozen.


#trauma

#hematology


Reference:


1. Matijevic N, Wang YW, Cotton BA, Hartwell E, Barbeau JM, Wade CE, Holcomb JB. Better hemostatic profiles of never-frozen liquid plasma compared with thawed fresh frozen plasma. J Trauma Acute Care Surg. 2013 Jan;74(1):84-90; discussion 90-1

Thursday, April 9, 2020

NEWS

Q: What are the six components of National Early Warning Score (NEWS)? 

Answer: 

NEWS is the European version of quick Sequential (Sepsis-related) Organ Failure Assessment score (qSOFA). It takes into account six basic parameters. It was initially released in 2012 and was updated (NEWS2) in 2017.    

  • respiration rate 
  • oxygen saturation 
  • systolic blood pressure 
  • pulse rate 
  • level of consciousness or new confusion 
  • temperature
There is no copyright for its use and is publicly available at 


#sepsis
#scores
#infectious-diseases


Reference:

Wednesday, April 8, 2020

Ultrasound in CIM/CIP

Q: Muscle ultrasound in Critical Illness Myopathy (CIM) and Critical Illness Polyneuropathy (CIP) will show? (select one) 

 A) increased echogenicity 
 B) decreased echogenicity 


 Answer:

Muscle ultrasound has a good prognostic value in CIM/CIP.  Increased echogenicity of major muscles like biceps, forearm, or mid-thigh muscles is found to be associated with a lower chance of discharge to home. It can be a useful tool to predict CIM/CIP in ICU patients with a sensitivity of 82 percent and specificity of 57 percent.



#neurology



Reference:


Kelmenson DA, Quan D, Moss M. What is the diagnostic accuracy of single nerve conduction studies and muscle ultrasound to identify critical illness polyneuromyopathy: a prospective cohort study. Crit Care 2018; 22:342.

Tuesday, April 7, 2020

Optic neuritis outcome

Q: 23-year-old female with past medical history of Multiple Sclerosis (MS) is admitted to ICU with severe optic neuritis. Which one test may predict between favorable or unfavorable outcome?



Answer:  aquaporin-4-specific serum antibodies

In general, African-Americans and patients with MS have less favorable prognosis in optic neuritis. In patients with MS prognosis can be predicted by measuring aquaporin-4-specific serum antibodies. Patients with aquaporin-4-specific serum antibodies may have poorer visual outcomes.


#neurology



References:


1. Martinez-Hernandez E, Sepulveda M, Rostásy K, et al. Antibodies to aquaporin 4, myelin-oligodendrocyte glycoprotein, and the glycine receptor α1 subunit in patients with isolated optic neuritis. JAMA Neurol 2015; 72:187.

2. Kimbrough DJ, Sotirchos ES, Wilson JA, et al. Retinal damage and vision loss in African American multiple sclerosis patients. Ann Neurol 2015; 77:228. 


3. Moss HE, Gao W, Balcer LJ, Joslin CE. Association of race/ethnicity with visual outcomes following acute optic neuritis: an analysis of the Optic Neuritis Treatment Trial. JAMA Ophthalmol 2014; 132:421.

Sunday, April 5, 2020

Opioid metabolites

Q: Most opioids are metabolized to their active metabolites via? (select one) 

 A) Liver 
B) Kidney


Answer: A

The objective of this question is to distinguish between two concepts. Most opioids are metabolized by the liver to thier active metabolites. These metabolites are excreted primarily by kidneys. Insufficiency of liver lead to accumulation of parent compound, and insufficiency of kidney can lead to accumulation of active metabolites. Both can result in toxicity but may present with two different manifestations..


#toxicology



References:


1. Smith HS. Opioid metabolism. Mayo Clin Proc. 2009;84(7):613–624. doi:10.1016/S0025-6196(11)60750-7 


 2. Glare PA, Walsh TD. Clinical pharmacokinetics of morphine. Ther Drug Monit 1991; 13:1.

Saturday, April 4, 2020

Bivalirudin and hemodialysis

Q; Bivalirudin (Angiomax) is removed by hemodialysis?

A) True
B) False


Answer: A

Bivalirudin is a parenteral direct thrombin inhibitor. It is a hirudin analog which is a mainstay of treatment in Heparin-Induced Thrombocytopenia (HIT). Bivalirudin may get removed by continuous renal replacement therapy (CRRT) and hemodialysis (HD), a very common scenario in ICU patients. 


This is an important clinical consideration as close monitoring of PTT is required to keep anticoagulation within the therapeutic range. In such renal patients, dose can range widely anywhere from 0.01 to 0.07 mg/kg per hour.


#pharmacology

#nephrology
#hematology


References:


1. Wisler JW, Washam JB, Becker RC. Evaluation of dose requirements for prolonged bivalirudin administration in patients with renal insufficiency and suspected heparin-induced thrombocytopenia. J Thromb Thrombolysis 2012; 33:287. 


2.  Tsu LV, Dager WE. Bivalirudin dosing adjustments for reduced renal function with or without hemodialysis in the management of heparin-induced thrombocytopenia. Ann Pharmacother 2011; 45:1185.

Friday, April 3, 2020

Propofol and bronchodilation

Q: Propofol has a bronchodilation property?

A) True
B) False


Answer: A 

 Propofol is highly lipophilic phenol derivative, and it can pass through blood-brain barrier. It has amnesic, anxiolytic, anticonvulsant, muscle relaxant and bronchodilation properties. Propofol’s bronchodilating effect is mediated via anticholinergic effects. It produces tracheal relaxation and inhibits contractions induced by histamine and prostaglandin F2-alpha.


#pulmonary

#pharmacology


References:


1. Hirota K, Sato T, Hashimoto Y et al: Relaxant effect of propofol on the airway in dogs. Anesthesiology 1997; 87: A1116. 


2. Pedersen CM, Thirstrup S, Nielsen-Kudak JE: Smooth muscle relaxant effects of propofol and ketamine in isolated guinea-pig trachea. Eur J Pharmacol 1993; 238: 75-80.

Thursday, April 2, 2020

ORT

Q: Palliative care service recommended to administer Opioid Risk Tool (ORT) to a patient getting transferred to long term care from ICU after trauma. What is ORT and its components?



Answer: Clinical instruments have been developed to identify patients for potential risk from misuse of prescribed opioids. ORT is a very simple questionnaire on five categories 
  1.  family history of substance use disorder 
  2. personal history of substance use disorder 
  3. age 
  4. history of preadolescent sexual abuse, and 
  5.  psychologic disease  
- Low risk: 0 to 3
- Moderate risk: 4 to 7
- High risk: ≥8

  #pharmacology



Reference:

Webster LR, Webster RM. Predicting aberrant behaviors in opioid-treated patients: preliminary validation of the Opioid Risk Tool. Pain Med 2005; 6:432.

Wednesday, April 1, 2020

Amiodarone and Liver

Q: What is the cut-off limit to consider discontinuation of Amiodarone in patients with liver insufficiency?


Answer: Two folds

There could be various reasons for elevated liver enzymes in an ICU patient. Amiodarone is one of the most commonly used drugs for atrial fibrillation in ICU. As per practice Guidelines of the North American Society of Pacing and Electrophysiology, it would be appropriate not to use or discontinue Amiodarone if serum transaminases are increased two folds from the normal.


Hyperbilirubinemia usually does not occur with Amiodarone. Unfortunately, if it occurs it stays elevated or continues to rise even if Amiodarone is discontinued due to its long half-life.


#hepatology

#pharmacology
#cardiology


References:


1. Goldschlager N, Epstein AE, Naccarelli G, et al. Practical guidelines for clinicians who treat patients with amiodarone. Practice Guidelines Subcommittee, North American Society of Pacing and Electrophysiology. Arch Intern Med 2000; 160:1741.

2. Chang CC, Petrelli M, Tomashefski JF Jr, McCullough AJ. Severe intrahepatic cholestasis caused by amiodarone toxicity after withdrawal of the drug: a case report and review of the literature. Arch Pathol Lab Med 1999; 123:251.