Tuesday, November 30, 2010

Q: Hypotension secondary to Milrinone therapy can be managed more efficiently with which pressor?

A) Norepinehrine
B) Dopamine
C) Vasopressin
D) Phenylephrine
E) Epinephrine



Answer: Vasopressin


Certainly any pressor can be use for hypotension but literature point towards vasopressin as better choice of pressor in milrinone induced hypotension. Low-dose vasopressin decreased the PVR/SVR ratio that was increased by milrinone. Considering the importance of maintaining systemic perfusion pressure as well as reducing right heart afterload, milrinone–vasopressin may provide better hemodynamics than milrinone–norephinephrine during the management of right heart failure.


Comparative hemodynamic effects of vasopressin and norepinephrine after milrinone-induced hypotension in off-pump coronary artery bypass surgical patients - Eur J Cardiothorac Surg 2006;29:952-956

Monday, November 29, 2010

How TIPSS is performed (Basics)



Sunday, November 28, 2010

Case: Why glove is more important than soap and water in prevention of spread of C. difficile-associated diarrhea (CDAD)?


Answer: Early experimental data suggest that, even using soap and water, the removal of C. diffile spores is more challenging than the removal or inactivation of other common pathogens. So preventing contamination of the hands via glove use remains the cornerstone for preventing Clostridium difficile transmission via the hands of healthcare workers.

Saturday, November 27, 2010

Case: 38 year old female presented to ER with severe pain going from "loin to groin". Patient has established diagnosis of Sarcoidosis?


Answer: Nephrolithiasis in sarcoidosis may be caused by hypercalcemia and hypercalciuria secondary to increase in 1,25-dihydroxyvitamin D and calcitriol production by activated macrophages. Hypercalcemia is generally treated with intravenous hydration. If EKG changes noted than systemic steroids are indicated. Ketoconazole is said to decrease 1,25-dihydroxyvitamin D and is helpful in minimizing hypercalcemia and hypercalciuria.

Friday, November 26, 2010

Case: 48 year old male presented to ER with Shortness of Breath. CXR showed massive left sided pleural effusion. ER physician inserted chest tube but to surprise white milky fluid get drained from chest. You made diagnosis of "Nontraumatic" Chylothorax. What are the 5 major causes of "Nontraumatic" Chylothorax?


Answer:

1.Lymphoma
2.cirrhosis,
3.tuberculosis,
4.sarcoidosis,
5.amyloidosis

Lymphoma is the most common cause of "Nontraumatic" Chylothorax, representing about 60% of all cases, with non-Hodgkin lymphoma more likely than Hodgkin lymphoma to cause a chylothorax. Trauma is the second leading cause of chylothorax (25%) including iatrogenic injury to the thoracic duct with thoracic procedures.

Pseudochylothorax: Chylothorax must be distinguished from pseudochylothorax, or cholesterol pleurisy, which results from accumulation of cholesterol crystals in a chronic existing effusion. The most common cause of pseudochylothorax is chronic rheumatoid pleurisy, followed by tuberculosis and poorly treated empyema.

Thursday, November 25, 2010

Wednesday, November 24, 2010

Q; The Model for End-Stage Liver Disease, or MELD, is a scoring system now used by the United Network for Organ sharing (UNOS) for prioritizing allocation of liver transplants. It takes in account all of the following EXCEPT?

A) Serum Bilirubin
B) Serum creatinine
C) INR
D) Stage of (hepatic) encephelopathy





Answer: D

MELD =
3.8 x log (e) (bilirubin mg/dL) + 11.2 x log (e) (INR) + 9.6 log (e) (creatinine mg/dL)

UNOS has made the following modifications to the score:

A) If the patient has been dialyzed twice within the last 7 days, then the value for serum creatinine used should be 4.0
B) Any value less than one is given a value of 1.


In interpreting the MELD Score in hospitalized patients, the 3 month mortality is:

40 or more — 71.3% mortality
30–39 — 52.6% mortality
20–29 — 19.6% mortality
10–19 — 6.0% mortality
less than 9 — 1.9% mortality

Tuesday, November 23, 2010

Q; Succinylcholine is contraindicated (relatively) for intubation in which poisoining?


Answer: Organophosphate poisoining.

Organophosphate may potentiate effects of succinylcholine. Succinylcholine is relatively contraindicated in Organophosphate poisoining.

Monday, November 22, 2010

Sengstaken Blakemore tube Insertion Video
(Language is spanish but procedure is well described)



Sunday, November 21, 2010

Q: 54 year old male patient with cirrhosis is stabalized and now ready to get transfer out of ICU. What is the preffered ratio of spironolactone and furosemide in the treatment of ascites to maintain eukalemia?



Answer: 100:40

First-line diuretic therapy for cirrhotic ascites is the combined use of spironolactone and furosemide. Both drugs can be titrated up as needed. To maintain normal electrolyte balance, the use of the 100 : 40 mg ratio of spironolactone to furosemide is generally recommended. Maximum accepted dosages are 400 and 160 mg/day of spironolactone and furosemide, respectively.



Management of Cirrhotic Ascites: Treatment of Cirrhotic Ascites - Medscape General Medicine. 2002;4(4)

Saturday, November 20, 2010

Q: While performing bubble echocardiography to diagnose hepatopulmonary syndrome - bubbles usually appear in left atrium within how many heart beats?



Answer: 7 heart beats

Intravenous microbubbles (from agitated normal saline) are normally obstructed by pulmonary capillaries. In hepatopulmonary syndrome they rapidly transit the dilated pulmonary vessels and appear in the left atrium usually within 7 heart beats.

The hepatopulmonary syndrome results from the formation of microscopic intrapulmonary arteriovenous dilatations in patients liver failure. The vascular dilatations cause overperfusion relative to ventilation, leading to ventilation-perfusion mismatch and hypoxemia.



Value of contrast echocardiography for the diagnosis of hepatopulmonary syndrome - European Journal of Echocardiography, Volume 8, Issue 5, Pp. 408-410.

Friday, November 19, 2010

A drop of hydrogen peroxide can differentiate exudative pleural effusion from transudate--development of a bedside screening test


BACKGROUND: There is no bedside test to classify pleural fluid as exudate or transudate. The aim of the present study is to develop such a test.

METHODS: We analyzed the Light's criteria parameters from bloodless pleural fluid and classified the biofluid as exudate or transudate and also estimated some parameters of oxidative stress in the biofluid by established spectrophotometric procedure. Two hundred microliters of sample was taken and added with 10 microl of 30% hydrogen peroxide followed by inspection of the sample for appearance of bubbles.

RESULT:

  • All exudative fluids (n=52) have shown appearance of profuse bubbles within 1 min of addition of hydrogen peroxide along with significantly more catalase activity compared to transudate.
  • All transudative fluids (n=32) have not shown bubble formation within 1 min after addition of hydrogen peroxide.
  • The exudate does not show bubble formation if supplemented with catalase inhibitors.
    Blood mixed transudate have shown profuse bubble formation after addition of hydrogen peroxide.

CONCLUSION: In the case of blood uncontaminated pleural fluid, this newly developed protocol's sensitivity and specificity will be equivalent to Light's criteria probably with more advantage as by this procedure transport of the sample to the clinical laboratory is not required due to its inherent simplicity.



A drop of hydrogen peroxide can differentiate exudative pleural effusion from transudate-development of a bedside screening test - Clin Chim Acta. 2009 Jul;405(1-2):83-6

Thursday, November 18, 2010

Bedside trick - getting peripheral venous access

In fast pace ICU enviroment central venous access has become a norm and basic skill of inserting peripheral IVs is lost somewhere in action. Before jumping to insert central line it is important to give good try in obtaining peripheral IVs for various reasons including avoidance of catheter related infections. Also short peripheral IV access with large bore is better than long central line for fluid resuscitation. Remember, the flow through a cannula is governed by the radius to the power 4 (r4) and the length of the cannula (Poiseuille's Law).

In case peripheral IV is hard to stick then you can try a quick trick. Get a small cannula (20-22 G) in a distal vein and then put a tourniquet higher up the arm and run in some IV fluid. This lead to the veins becoming visible in the ante-cubital fossa, and you can now get the large bore cannula in.

Wednesday, November 17, 2010

Nitroglycerin in difficult-to-wean COPD patients?

Both experimental and clinical data give convincing evidence to acute cardiac dysfunction as the origin or a cofactor of weaning failure in patients with chronic obstructive pulmonary disease. Therefore, treatment targeting the cardiovascular system might help the heart to tolerate more effectively the critical period of weaning. This study aims to assess the hemodynamic, respiratory and clinical effects of nitroglycerin infusion in difficult-to-wean patients with severe chronic obstructive pulmonary disease.

Methods Twelve difficult-to-wean (failed [greater than or equal to] 3 consecutive trials) chronic obstructive pulmonary disease patients, who presented systemic arterial hypertension (systolic blood pressure [greater than or equal to] 140mmHg) during weaning failure, and had systemic and pulmonary artery catheters in place participated in this prospective, interventional, non-randomized clinical trial. Patients were studied in two consecutive days, i.e., the first day without (Control day) and the second day with (Study day) nitroglycerin continuous intravenous infusion starting at the beginning of the spontaneous breathing trial, and titrated to maintain normal systolic blood pressure. Hemodynamic, oxygenation and respiratory measurements were performed on mechanical ventilation, and during a 2-hour T-piece spontaneous breathing trial. Primary endpoint was hemodynamic and respiratory effects of nitroglycerin infusion. Secondary endpoint was spontaneous breathing trial and extubation outcome.

Results

  • Compared to mechanical ventilation, mean systemic arterial pressure, rate-pressure product, mean pulmonary arterial pressure, and pulmonary artery occlusion pressure increased [from (mean+/-SD) 94+/-14, 13708+/-3166, 29.9+/-4.8, and 14.8+/-3.8 to 109+/-20mmHg, 19856+/-4877mmHg b/min, 41.6+/-5.8mmHg, and 23.4+/-7.4 mmHg, respectively], and mixed venous oxygen saturation decreased (from 75.7+/-3.5 to 69.3 +/- 7.5%) during failing trials on Control day, whereas they did not change on Study day.
  • Venous admixture increased throughout the trial on both Control day and Study day, but this increase was lower on Study day.
  • Whereas weaning failed in all patients on Control day, nitroglycerine administration on Study day enabled a successful spontaneous breathing trial and extubation in 92% and 88% of patients, respectively.


Conclusions In this clinical setting, nitroglycerin infusion can expedite the weaning by restoring weaning-induced cardiovascular compromise.



Nitroglycerin can facilitate weaning of difficult-to-wean COPD patients: a prospective interventional non-randomized study - Critical Care 2010, 14:R204

Tuesday, November 16, 2010

Q: 44 year old female is admitted to ICU with hypovolemia after chemotherapy session and continue to have severe nausea and bouts of vomitting. All conventional anti emetics failed to control her symptoms. Can you use propofol as anti emetic without getting patient intubate?



Answer: Yes

Propofol has a good antiemetic effect at low dose (subhypnotic dose) when other anti emetics fail in severe nausea and vomitting after surgey or chemotherapy sessions. It can be given as a continuous infusion of 1 mg /kg/hr or as single dose of 10 mg(1 cc) which provides relief for about 30 minutes. Propofol acts directly on the chemoreceptor trigger zone, vagal nuclei, and other centers implicated in nausea and vomiting.



References:

1. Subhypnotic doses of propofol possess direct antiemetic properties. Anesth Analg. 1992 Apr;74(4):539-41.

2. When Nothing Helps: Propofol as Sedative and Antiemetic in Palliative Cancer Care - Journal of Pain and Symptom Management Volume 30, Issue 6, December 2005, Pages 570-577

3. Prevention of postoperative nausea and vomiting by continuous infusion of subhypnotic propofol in female patients receiving intravenous patient‐controlled analgesia - Br. J. Anaesth. (2000) 85 (6): 898-900.

Monday, November 15, 2010

RIFLE Criteria

Acute Dialysis Quality Initiative (ADQI) Working Group has developed the RIFLE (risk, injury, failure, loss and end-stage renal failure) criteria which provides a graded classification of Renal failure. Aim is to identify the different stages of disease progression. It has become a standard and intensivists should keep themselves abreast with it.



Sunday, November 14, 2010

Serial Lactic acid level in acetaminophen toxicity


Q: 22 year old female presented to ED after 4 hours of Tylenol (acetaminophen) toxicity. Lactic acid level is 5 mmol/L. After 12 hours it is 4 mmol/L. What does it signifies?



Answer: Poor prognosis

If lactate levels are high at 4 hours (more than 3.5 mmol/L) and remain elevated at 12 hours (more than 3.0 mmol/L) - are early predictors of outcome in acetaminophen-induced acute liver failure. Lactate levels are elevated as a result of both impaired tissue perfusion and decreased clearance by the liver.

Transfer to tertiary care center for transplant should be considered.




References:

1. Macquillan GC, Seyam MS, Nightingale P, Neuberger JM, Murphy N. Blood lactate but not serum phosphate levels can predict patient outcome in fulminant hepatic failure. Liver Transpl 2005; 11: 1073–1079.

2. Bernal W, Donaldson N, Wyncoll D, Wendon J. Blood lactate as an early predictor of outcome in paracetamol-induced acute liver failure: a cohort study. Lancet 2002; 359: 558–563.

Saturday, November 13, 2010

Acute cerebral and pulmonary edema induced by hemodialysis - bench to bed research

Background: The dialysis disequilibrium syndrome is characterized by neurologic deterioration and cerebral edema which occurs after hemodialysis. The purpose of this study was to investigate the pathogenesis of acute cerebral and pulmonary edema induced by hemodialysis.

Methods: We evaluated the effects of hemodialysis on the biochemical and hemodynamic parameters of the plasma and cerebrospinal fluid, including the intracranial pressure, dry/wet ratio, and pulmonary edema index, and we also examined the pathological changes of the brain and lung tissue in dogs suffering from uremia.

Results: Seventy-two hours after bilateral ureteral ligation, 10 uremic dogs were hemodialyzed for 2 hours, yielding a 73.6% and 60.1% decrease in the plasma urea and creatinine, respectively, a decrease in the plasma osmolality from (359±18) mOsm/kgH2O to (304±6) mOsm/kgH2O , a decrease in the dry/wet ratio of the lung and brain tissue, and an increase in the hemodynamic parameters (right atrial pressure, right ventricular pressure, pulmonary artery pressure, pulmonary capillary wedge pressure, and central venous pressure), intracranial pressure, total pulmonary resistance index, and pulmonary edema index. Moreover, the pathological examination revealed lung and brain edema in the dialyzed dogs. This group was compared to 3 control groups: 6 uremic dogs which were sham dialyzed without dialysate so that no fall in the plasma urea occurred, and 12 uremic and 12 nonuremic animals that were not dialyzed. However, the parameters mentioned above were not significantly changed among these 3 control groups.


Conclusions: The acute brain and lung edema in our model appeared to be primarily due to a large osmotic gradient between the plasma and the brain and lung. This is the “urea reverse effect” which promoted the osmotically-induced lung and brain swelling.



Acute cerebral and pulmonary edema induced by hemodialysis - Chinese Medical Journal - 2008;121(11):1003-1009

Friday, November 12, 2010

Thursday, November 11, 2010

Q: Indomethacin makes nephrogenic Diabetes Insipidus (choose one)

A) Worse
B) Better
C) No response

- choose one



Answer: B

Indomethacin has shown to help in nephrogenic diabetes insipidus particulary in drug induced diabetes insipidus like lithium. Most of the literature and case reports in this regard are 20-25 years old but recently there is a renewed interest in this phenomenon.

1. Indomethacin in streptozocin-induced nephrogenic diabetes insipidus - American Journal of Kidney Diseases Volume 9, Issue 1 , Pages 79-83, January 1987

2. Indomethacin in the treatment of lithium-induced nephrogenic diabetes insipidus, Arch Intern Med. 1989 May;149(5):1123-6.

3. Pharmacologic Treatment of Congenital Nephrogenic Diabetes Insipidus - clinicaltrials.gov

Wednesday, November 10, 2010

A note on Factor 7 (rVIIa) and thrombocytopenia

Factor 7 (rVIIa - Novoseven) is now significantly use as off label in uncontrolled bleeding. It may not be efective in the presence of severe thrombocytopenia and should be corrected prior to its administration. Although there are case reports of the successful use of rVIIa in severe thrombocytopenia, a low platelet count is likely to predict a poor or partial response to rVIIa therapy.

Its haemostatic effects are mediated by the thrombin it generates by both tissue factor (TF) dependent and independent mechanisms. The TF independent mechanism requires platelets for the direct activation of Factor X on their surface by rVIIa.

Tuesday, November 9, 2010

Q: According to new 2010 ACLS guidelines what is the recommendation for jellyfish stings?


Answer: To iactivate venom load and prevent further envenomation, jellyfish stings should be liberally washed with vinegar (4% to 6% acetic acid solution) ASAP for at least 30 seconds. After the nematocysts are removed or deactivated, the pain from jellyfish stings should be treated with hot water immersion when possible. Literature shows that vinegar is most effective for inactivation of the nematocysts. Immersion with water, as hot as tolerated for about 20 minutes, is most effective for treating the pain.

Monday, November 8, 2010

Q: Name 3 unusual complications of Propofol beside propofol infusion syndrome?


Answer:
  • Dystonia and myoclonic movements
  • Euphoria (also sexual hallucinations)
  • Priapism

Sunday, November 7, 2010

Editors' note: Following is a very important video to watch as ultrasound based diagnosis of pneumothorax is becoming more and more a standard. It will be available in our video section.



Saturday, November 6, 2010

Q: 42 year old male with well known history of cirrhosis is admitted with shortness of breath. Clinical exam showed ascites and CXR showed hydrothorax. Paracentesis is performed in ER with some relief. Chest tube is planned by ER resident. Why it would be a bad idea to insert - particularly a large bore chest tube in a patient with hydrothorax?



Answer: Insertion of chest tube in hydrothorax is a bad idea as it usually results in uncontrollable fluid loss and has a high mortality secondary to hypovolemic shock. Therapeutic thoracocentesis with albumin replacement may provide temporary relief but may refill again. Thoracocentesis combined with pleurodesy, LeVeen or Denver shunt or surgical repair are other options. Management of underlying cause is warranted like placement of TIPS.

Friday, November 5, 2010

Q: 21 year old female is admitted with severe headache. There is no past medical history except she is recently started on Minocycline for the treatment of her acne. What is your suspicion?



Answer: Pseudotumor cerebri (PTC) or idiopathic intracranial hypertension

Tetracycline, Doxycycline and Minocycline are known to cause PTC.The mechanism by which they induce pseudotumor cerebri is not known.

Minocycline may cause persistently elevated intracranial pressure, and may require medical and surgical treatment beyond discontinuation of the medication. It is not a benign condition and and aggressive interventions are needed to prevent severe morbidity like vision loss.



References:

  • A. M. Chiu, W. L. Chuenkongkaew, W. T. Cornblath, et al., “Minocycline treatment and pseudotumor cerebri syndrome,” American Journal of Ophthalmology, vol. 126, no. 1, pp. 116–121, 1998.
  • K. Mochizuki, T. Takahashi, M. Kano, K. Terajima, and N. Hori, “Pseudotumor cerebri induced by minocycline therapy for acne vulgaris,” Japanese Journal of Ophthalmology, vol. 46, no. 6, pp. 668–672, 2002.
  • D. I. Friedman, L. K. Gordon, R. A. Egan, et al., “Doxycycline and intracranial hypertension,” Neurology, vol. 62, no. 12, pp. 2297–2299, 2004.
  • A. Kesler, Y. Goldhammer, A. Hadayer, and P. Pianka, “The outcome of pseudotumor cerebri induced by tetracycline therapy,” Acta Neurologica Scandinavica, vol. 110, no. 6, pp. 408–411, 2004.

Thursday, November 4, 2010

Q: 21 year old male is admitted from ER with acute respiratory failure. Patient is intubated. CXR shows bilateral ARDS. You started antibiotics. There is no significant past medical history.Brother told you patient just started smoking. You decide to perform bronchoscopy. What is your suspicion?



Answer: Acute eosinophillic pneumonia

Increasing body of evidence suggest close association between new onset or even change in smoking habit and acute eosinophillic pneumonia. Suspicion should be high in yound patients presenting with acute respiratory distress. Early diagnosis is crucial as patients with AEP respond rapidly to high doses of systemic corticosteroids.



Uchiyama H, Suda T, Nakamura Y, et al. Alterations in smoking habits are associated with acute eosinophilic pneumonia. Chest. May 2008;133(5):1174-80

Wednesday, November 3, 2010

Q: What does it mean by Cryptic Shock?



Answer:The term "cryptic shock" is used for patients with deceptively normal hemodynamic parameters, yet have high morbidity and mortality because of global ischemia with increased lactate blood level. It is also called "normotensive shock". Even "hypertensive shock" is described as in cardiogenic shock but with marked sympathetic system activation or during a hypertensive crisis due to pheochromocytoma with evidence of tissue hypoxia (high lactate blood level).

Tuesday, November 2, 2010

Q: Pre-oxygenation (or denitrogenation) is an important step during intubation. What length of time is good to perform pre-oxygenation to avoid rapid hypoxemia during intubation?



Answer: About 3 minutes


Nitrogen constitutes about 79% of air. Goal of pre-oxygenation is to replace nitrogen at the alveolar level causing nitrogen washout and creating an oxygen reservoir in the functional residual capacity of the lungs. Most of denitrogenation occurs in 2 minutes. Good preoxygenation of about 3 minutes may provide up to 8 minutes of apnea time in otherwise healthy adults but the desaturation rate is more rapid in sicker patients because of their higher metabolic rate and underlying pulmonary disease such as ARDS.

Various methods to provide good preoxygenation includes high-flow oxygen via a nonrebreather face mask (spontaneously breathing patient) or by using Ambu bag. 8 deep breaths over 60 seconds by using full vital capacity should provide good pre-oxygenation. Also BiPap mask is a good way of performing good denitrogenation. Patients on non-invasive mask ventilation should be left on it till intubation procedure is set to perform.

Monday, November 1, 2010

Q: Why Daptomycin is a bad choice for use in Pneumonia?


Answer: Daptomycin is a bad choice in the treatment of respiratory tract infections because surfactant in lungs binds daptomycin, leaving free drug concentrations in pulmonary secretions to very minimal. This is the only known organ-specific inhibition of an antibiotic.


Inhibition of daptomycin by pulmonary surfactant: in vitro modeling and clinical impact. - J Infect Dis. 2005 Jun 15;191(12):2149-52.