Saturday February 27, 2010

Case: 57 year old female, newly hemodialysis patient, transferred from floor to ICU after she developed seizure at the end of her dialysis session. No significant risk factor could be find otherwise. Nurse reports patient appear irritable and restless before episode and complain of headache, nausea and blurred vision. While resident was called to evaluate as patient also noticed to have muscular twitching and confusion, symptoms progressed and seizure was witnessed.

Answer: Dialysis disequilibrium syndrome.

Dialysis disequilibrium syndrome is common during hemodialysis particularly patient’s first few dialysis sessions. It is characterized by neurologic symptoms of varying severity and actually may lead to herniation and death. The rapid reduction in BUN lowers the plasma osmolality, creating a transient osmotic gradient that promotes water movement into the cells, causing cerebral edema and consequently acute neurologic dysfunction. With better understanding of the process and newer dialysis techniques, severe form of syndrome is now not commonly seen. This not only explains that why our nephrology colleagues start with gentle but frequent sessions but also explains one of the several benefits of mannitol during dialysis.

Read interesting article from University of Calgary, Alberta, Canada : Dialysis Disequilibrium Syndrome: Brain death following hemodialysis for metabolic acidosis and acute renal failure - A case report followed with discussion and different management modalities (Ref.: BMC Nephrol. 2004; 5: 9.)

Friday February 26, 2010
CHADS2 Score

Several risk factor assessment algorithms have been developed to aid the clinician in decision-making regarding anticoagulation in atrial fibrillation. The CHADS2 index (Cardiac failure, Diabetes, Stroke [or S2 = TIA]) is the most widely used of these algorithms. The CHADS2 index uses a point system to determine yearly thromboembolic risk. Two points are assigned for a history of stroke or TIA, and one point is given for age over 75 or a history of hypertension, diabetes, or heart failure. High scores were associated with an increased rate of stroke.


CHF Hx = +1

HTN Hx = +1

Age 75 or above = +1

Diabetes Mellitus Hx = +1

Stroke previously or TIA Hx = +2


Warfarin is recommended for score 2 and above

Thursday February 25, 2010


Q: What is the maximum joules you can use to cardiovert refractory atrial fibrillation?


Answer: 720 Joules

Energy requirements for atrial fibrillation are 100-200 J initially and 360 J for subsequent shocks. But for refractory atrial fibrillation a study has shown good response to higher energy shocks of 720 J.




Saliba W, Juratli N, Chung MK, Niebauer MJ, Erdogan O, Trohman R. Higher energy synchronized external direct current cardioversion for refractory atrial fibrillation. J Am Coll Cardiol. Dec 1999;34(7):2031-4

Wednesday February 24, 2010


Q: What is takotsubo cardiomyopathy?


Answer: Takotsubo cardiomyopathy, also known as broken-heart-syndrome, or simply stress cardiomyopathy, is a type of non-ischemic cardiomyopathy.

The hallmark of the disease is bulging out of the apex of the heart with preserved function of the base that earned the syndrome its name "tako tsubo", or octopus trap in Japan, where it was first described.The cause appears to involve high circulating levels of catecholamines. If individual survives their initial presentation, patient usually improves within 2 months. For unknown reason - Takotsubo cardiomyopathy is more commonly seen in post-menopausal women.

Tuesday February 23, 2010

Picture Quiz

Answer: Dextrocardia
(with situs inversus, single atrium, VSD and pulmonary hypertension)

Monday February 22, 2010

Interesting picture: Bilateral Renal Vein Thrombosis
(see filling defects)

Saturday February 20, 2010

Editors' note: This is not a pearl but may help people looking for generic templates

Sample Central Venous Catheter Placement Procedure Note

Date ________ Time ______

□ New central venous catheter □ Guide wire exchange

Indications: □ Hemodynamic monitor/instability

Diagnosis: ____________________

□ Medications require central venous access
□ Inability to get peripheral access ___________________
□ Acute short term hemodialysis/apheresis
□ Infusion of > 3 incompatible continuous infusions or 2 continuous infusions plus blood product



Consent:

□ Informed consent was obtained from _____________
□ This procedure was done emergently


Insertion Site: □ Right □ Left

□ Subclavian
□ Jugular
□ Femoral (indication required) _________
□ Other sites where placement attempted _________

Type of catheter:

□ Non-tunneled □1 □2 □3 □4 lumens
□ Introducer
□ Pulmonary artery

□ Antiseptic impregnated
□ Dialysis catheter

□ Other__________


Skin Prep:

□ Chlorhexidine (preferred)

□ Povidone iodine


Ultrasound guided: □ Yes □ No

Conditions:

□ Sterile barriers: Sterile gloves, sterile gown, cap, mask, large sterile drape
□ Anesthetized site with lidocaine
□ Patient in Trendelenberg position
□ Modified Seldinger technique
□ New sterile gloves used to insert catheter during guidewire exchange
□ Sterile field maintained throughout procedure
□ Emergent line placement (consider replacement in 24 hours)


Following Procedure:

□ Blood was aspirated from all lumens, ports were flushed, and a sterile dressing was placed
□ Chest x-ray was ordered for SC and IJ attempt(s)
□ Patient tolerated without immediate complications
□ Patient experienced complications:
□ Bleeding □ EBL _________
□ Hematoma
□ Pneumothorax
□ Arterial puncture
□ Air embolism
□ Neurologic changes
□ Other __________________________


Additional comments: ____________________________________________

Time spent performing the procedure _____________


Performed by (check one)

□ Attending □ Resident/Fellow

Signature ____________________
Print name_________


Attending physician present during critical portion(s) of procedure

Attending Signature _________________
Attending name_________________________

Friday February 19, 2010

Fiberoptic intubation

Thursday February 18, 2010


Q; What is 'Buffalo chest’?


Answer: An interpleural communication results in a single pleural space within a chest (or communicating pneumothoraces on both sides of chest) is called "Buffalo chest'.

Background: Each lung is enveloped in a pleural sac. The pleural sac consists of two serous membranes: the parietal pleura, which lines the thoracic wall, mediastinum and diaphragm; and the visceral pleura, which invests the lung. A potential space called the pleural cavity exists between the parietal and visceral pleura. A pneumothorax occurs when air fills this cavity. The two pleural sacs are separate structures therefore, a pneumothorax is unilateral, unless a communication exists between each pleural cavity.

A communication between each hemithorax can be congenital, iatrogenic or traumatic. It has been reported after procedures involving median sternotomy, laparoscopic surgery and heart and lung transplants. In surgical cases, the communication results from the disruption of the anterior pleural reflections.

An interpleural communication results in a single pleural space. This is termed ‘Buffalo chest’ because North American buffalo, or bison, lack an anatomical separation between the two hemithoraces. This facilitated death by bilateral tension pneumothoraces from a hunter's single arrow to the chest.

There should be a complete resolution of the ipsilateral and contralateral pneumothoraces via the single chest drain.

Wednesday February 17, 2010


Q; What is Upshaw-Schülman syndrome (USS)?

Answer: A hereditary form of TTP (thrombotic thrombocytopenic purpura) is called the Upshaw-Schülman syndrome. Patients with this condition develop TTP in clinical situations with increased von Willebrand factor levels, e.g. infection. About 5-10% of all TTP cases are due to Upshaw-Schülman syndrome.

Patients with Upshaw-Schulman syndrome (USS) have repeated episodes of thrombocytopenia and microangiopathic hemolytic anemia that respond to infusions of fresh frozen plasma. Inheritance of USS has been thought to be autosomal recessive, because 2 siblings in the same family are often affected but their parents are asymptomatic.

Tuesday February 16, 2010

Q; The average life span of a platelet in the blood is 10 days but what is the average life span of transfused Platelets?


Answer: The average life span of a platelet in the blood is 10 days but transfused platelets have a short life-span, 3-4 days.

Monday February 15, 2010
Rule of thumb for adjusting Amiodarone with Coumadin


Amiodarone 400 mg/day: Reduce Warfarin dose 40%
Amiodarone 300 mg/day: Reduce Warfarin dose 35%
Amiodarone 200 mg/day: Reduce Warfarin dose 30%
Amiodarone 100 mg/day: Reduce Warfarin dose 25%

Sunday February 14, 2010
Female preponderance in ibutilide-induced torsade de pointes

Objective: Ibutilide, a class III antiarrhythmic agent used for pharmacological cardioversion of atrial arrhythmias, has a potential to cause QT-interval prolongation and torsade de pointes. Purpose of this study was to determine whether women are more prone to develop ibutilide-induced torsade de pointes.

Methods: All clinical trials, cases, case series, and related articles in English-language in addition to 51 patients from our institution on the subject were examined.

Results: In a database derived from 23 reports in literature and from our institution, 1720 patients received ibutilide for cardioversion of atrial arrhythmias. Only in 87% (n=1492) patients, data were reported whether or not ibutilide caused torsade de pointes.

The overall incidence of torsade de pointes was 3.9% (n=58) patients.

Data on sex distribution of ibutilide-induced torsade de pointes was available in 73% (n=1096) patients. Torsade de pointes developed in 17 (5.6%) of 304 women and 24 (3%) of 792 men (P=0.05). It occurred during or within 45 min after completion of the infusion of ibutilide.

Treatment instituted was with intravenous magnesium sulfate alone in 14% (n=8) patients, magnesium sulfate plus lidocaine in 5% (n=3) patients, magnesium sulfate with electrical cardioversion in 17% (n=10) patients, electrical cardioversion alone in 19% (n=11) patients, and precordial thump in 3% (n=2) patients.

In 41% (n=24) of patients who developed torsade de pointes, it resolved without treatment.

There were no reported deaths secondary to torsade de pointes associated with ibutilide infusion.

Conclusion: Incidence of ibutilide-induced torsade de pointes is higher in women than in men. Greater caution must be observed while using ibutilide in women.



Female preponderance in ibutilide-induced torsade de pointes - International Journal of Cardiology, Volume 95, Issue 2, Pages 219-222

Saturday February 13, 2010
Picture Quiz

KUB in a patient presenting with acute abdominal pain.

Tips: Thumbprinting in the region of the splenic flexure and dilatation of the proximal small-bowel.

Answer: Ischemic colitis.

Ischemic colitis occurs due to any clinical condition which cause insufficient blood supply to a segment or the entire colon. This disease results in ischemic necrosis of varying severities that can range from superficial mucosal involvement to full-thickness transmural necrosis. Patients usually present with colicky abdominal pain associated with vomiting, diarrhea, or rectal bleeding

Friday February 12, 2010
About Dabigatran

Dabigatran is an anticoagulant from the class of the direct thrombin inhibitors. It is being studied for various clinical indications and may replace warfarin as the preferred anticoagulant in many cases. Unlike warfarin it works right away and does not require INR monitoring.

Phase 3 clinical trials are ongoing in treatment and prevention of secondary venous thromboembolism (VTE) in post-operative orthopedic patients; long-term prophylaxis in acute coronary syndrome and stroke patients with atrial fibrillation and symptomatic VTE because of various causes. Dabigatran at doses of 150 mg and 220 mg once daily when compared with the standard 40 mg dose of enoxaparin once daily, confirmed that dabigatran performed as well as enoxaparin in preventing thrombosis, with a similar risk profile.

Absorption is unrelated to food but may be decreased if taken with a proton pump inhibitor. Metabolism is slowed in people taking quinidine, verapamil, or amiodarone.

Approval from FDA is expected in 2010.

Thursday February 11, 2010
Is fresh blood better ?

Results of one study span over 10 years including 12,264 patients (total median transfusion of 4 pRBC units), done at Mayo Clinic, Rochester, MN - found that

• adjusted in-hospital mortality was 5% if pRBC was stored for less than 7 days
• adjusted in-hospital mortality was 8% if pRBC was stored for 7-14 days
• adjusted in-hospital mortality was 13% if pRBC was stored for more than 14 days

This corresponds to a reduction in the risk of in-hospital mortality of 62% for patients receiving pRBC stored for less than 7 days.


Reference: ATS 2007 poster presentations: The 2007 International Conference Abstracts of the American Thoracic Society (ATS) are published in the American Journal of Respiratory and Critical Care Medicine, Volume 175, Abstracts Issue, April 2007.

Wednesday February 10, 2010
A protocol of no sedation for critically ill patients receiving mechanical ventilation: a randomised trial

Background: Standard treatment of critically ill patients undergoing mechanical ventilation is continuous sedation. Daily interruption of sedation has a beneficial effect, and in the general intesive care unit of Odense University Hospital, Denmark, standard practice is a protocol of no sedation. We aimed to establish whether duration of mechanical ventilation could be reduced with a protocol of no sedation versus daily interruption of sedation.

Methods: Of 428 patients assessed for eligibility, we enrolled 140 critically ill adult patients who were undergoing mechanical ventilation and were expected to need ventilation for more than 24 h. Patients were randomly assigned in a 1:1 ratio (unblinded) to receive:

• no sedation (n=70 patients); or
• sedation (20 mg/mL propofol for 48 h, 1 mg/mL midazolam thereafter) with daily interruption until awake (n=70, control group).

Both groups were treated with bolus doses of morphine (2·5 or 5 mg).

The primary outcome: was the number of days without mechanical ventilation in a 28-day period, and we also recorded the length of stay in the intensive care unit (from admission to 28 days) and in hospital (from admission to 90 days).

Findings: 27 patients died or were successfully extubated within 48 h, and, as per our study design, were excluded from the study and statistical analysis.

• Patients receiving no sedation had significantly more days without ventilation (n=55; mean 13·8 days) than did those receiving interrupted sedation (n=58; mean 9·6 days, p=0·0191).
• No sedation was also associated with a shorter stay in the intensive care unit (p=0·0316), and, for the first 30 days studied, in hospital (p=0·0039), than was interrupted sedation.
• No difference was recorded in the occurrences of accidental extubations, the need for CT or MRI brain scans, or ventilator-associated pneumonia.
• Agitated delirium was more frequent in the intervention group than in the control group(p=0·0400).
  

Interpretation: No sedation of critically ill patients receiving mechanical ventilation is associated with an increase in days without ventilation. A multicentre study is needed to establish whether this effect can be reproduced in other facilities.



A protocol of no sedation for critically ill patients receiving mechanical ventilation: a randomised trial - The Lancet, Volume 375, Issue 9713, Pages 475 - 480, 6 February 2010

Tuesday February 9, 2010
On Vimpat (lacosamide)

Lacosamide is a medication for the adjunctive treatment of partial-onset seizures and diabetic neuropathic pain.

The precise mechanism underlying the anti-epileptic effects of lacosamide is not fully clear but it is said that lacosamide selectively enhances slow inactivation of voltage-gated sodium channels, resulting in stabilization of hyperexcitable neuronal membranes. lacosamide is found to significantly reduce seizure frequency when given in addition to other antiepileptics, at doses of 400 and 600 milligrams a day. In diabetic neuropathy, lacosamide also provided significantly better pain relief when compared to placebo.

The apparent lack of sedative effects makes this agent attractive for patients who are prone to develop somnolence with other anti-epileptic drugs(AEDs). On the other hand, reports of potential electrocardiogram changes with lacosamide suggest that caution is needed before using this drug in patients with pre-existing cardiac disease and in those taking drugs known to cause PR prolongation.

Monday February 8, 2010


Q; Patient with C. Diff. Colitis is having no improvement with PO Flagyl. You ordered PO Vancomycin. Pharmacy informed you that PO Vancomycin is not available. What would be your trick of trade here?


A; Actually, IV Vancomycin can be given via oral route. It works just as well, and a lot cheaper. The ordered dose may be diluted in water and given to the patient to drink. Common flavoring syrups may be added to the solution to improve taste.

Sunday February 7, 2010
Picture Diagnosis


CT scan with a mass, round with well defined borders. Note: thick-walled cavity with low attenuation center and contrast-enhanced periphery




Answer: Amebic liver abscess

Amebic liver abscess is the most frequent extraintestinal manifestation of Entamoeba histolytica infection. This infection is caused by the protozoa E histolytica, which ascends the portal venous system. Amebic liver abscess is an important cause of space-occupying lesions of the liver, mainly in developing countries

Saturday February 6, 2010


Q: All of the following can be use as treatment of hyponatremia in Cerebral salt wasting (CSW) after Subarachnoid hemorrhage except:

A) Hypertonic saline (3%)

B) Normal Saline or Salt tablets

C) Conivaptan (Vaprisol)

D) Fluid restriction

E) fludrocortisone (Florinef)


Answer: D

Overall, the treatment for hyponatremia in CSW is aimed at restoring normovolemia with normal serum sodium levels. Often if the patient is without symptoms, aggressive treatment is unnecessary.

In general, patients with CSW will receive an order for intravenous normal saline. Depending on the sodium and fluid balance and the patient's symptoms, hypertonic 3% saline at an initial rate of 25-50 ml/hour, 325 mg salt tablets, and/or 1-2 mg daily of oral fludrocortisone (Florinef) may also be used.

In SIADH, the preferred treatment in the general population is fluid restriction. However, in patients with aneurysmal Subarachnoid hemorrhage (SAH), great care must be taken because of the risk of vasospasm in these patients. It carries risk of increased incidence of infarction in patients treated for supposed SIADH with fluid restriction. Other types of treatment include the infusion of hypertonic saline in conjunction with loop diuretics or newly available arginine vasopressin antagonist (Conivaptan).

Friday February 5, 2010
Cialis/Viagra in the treatment of cerebral vasospasm


Background The pathogenesis of cerebral vasospasm is likely to be multifactorial. Strong evidence has indicated that decreasing levels of NO after SAH seem to be important. A PDE-V inhibitor, tadalafil, theoretically increases NO levels. Our study investigated the vasodilatory efficacy of tadalafil on the cerebral arteries with measurement of basilar artery diameters on angiography.


Methods We used 42 male Wistar-Albino rats to test our hypothesis. They were assigned randomly into the following seven groups:

group 1: control (only saline),
group 2: SAH only (killed on day 2),
group 3: SAH + tadalafil (killed on day 2),
group 4: SAH only (killed on day 4),
group 5: SAH + tadalafil (killed on day 4),
group 6: saline + tadalafil (killed on day 2) and
group 7: saline + tadalafil (killed on day 4).

The three different parts of basilar artery diameters were measured angiographically.

Results

• There were statistically significant differences between the SAH and SAH groups treated with tadalafil at days 2 and 4.
• Comparison between control and tadalafil groups showed no significant differences. This result indicated that tadalafil has a vasodilatory effect on vasoconstricted arteries, but no effect on normal basilar arteries.
  
  Conclusion Our study results showed that tadalafil has a vasodilatory effect on both acute and chronic periods of cerebral vasospasm. We also concluded that cerebral angiography can be used safely for investigation of cerebral vasospasm in animal studies.
  
  
  A new approach to the treatment of cerebral vasospasm: the angiographic effects of tadalafil on experimental vasospasm - Acta Neurochirurgica, - Published online: 20 October 2009

Thursday February 4, 2010


Q: It is well known that Keppra (levetiracetam) is eliminated via renal route. Approximately how much of levetiracetam is removed during a standard 4-hour hemodialysis procedure?


Answer: Approximately 50% of the pool of levetiracetam in the body is removed during a standard 4-hour hemodialysis procedure. Supplemental doses should be given to patients after dialysis.

Clearance of levetiracetam is correlated with creatinine clearance. Total body clearance of levetiracetam is reduced in patients with impaired renal function by 40% in the mild group (CLcr = 50-80 mL/min), 50% in the moderate group (CLcr = 30-50 mL/min) and 60% in the severe renal impairment group (CLcr less than 30 mL/min). In anuric (end stage renal disease) patients, the total body clearance decreased 70% compared to normal subjects.

Wednesday February 3, 2010
Ethics in Medicine - The Rule of Double Effect (RDE)


RDE stipulates that 4 conditions must be met before an act with both good and bad consequences may be morally justified.

1. The nature of the act. The act itself must not be intrinsically wrong and not be in a category that is absolutely prohibited.
2. The agent's intention. The agent must intend only the good and not the bad effect, although the bad effect, such as respiratory depression following administration of opiates, may be foreseen but not intended.
3. The distinction between means and effects. The bad effect, such as death, must not be the means used to bring about the good effect, such as the relief of suffering.
4. Proportionality between the good effect and the bad effect. An action is undertaken for a proportionally grave reason for permitting the foreseen bad effect.
   

Tuesday February 2, 2010
Silver Coated ETT?

Objective To determine whether a silver-coated endotracheal tube would reduce the incidence of microbiologically confirmed VAP.

Design Prospective, randomized, single-blind, controlled study conducted in 54 centers in North America. A total of 9417 adult patients were screened between 2002 and 2006. A total of 2003 patients expected to require mechanical ventilation for 24 hours or longer were randomized.

Main Outcome Measures Primary outcome was VAP incidence based on quantitative bronchoalveolar lavage fluid culture with 104 colony-forming units/mL or greater in patients intubated for 24 hours or longer. Other outcomes were VAP incidence in all intubated patients, time to VAP onset, length of intubation and duration of intensive care unit and hospital stay, mortality, and adverse events.


Results :

• Among patients intubated for 24 hours or longer, rates of microbiologically confirmed VAP were 4.8% (37/766 patients) in the group receiving the silver-coated tube and 7.5% (56/743) (P = .03) in the group receiving the uncoated tube with a relative risk reduction of 35.9%
• The silver-coated endotracheal tube was associated with delayed occurrence of VAP (P = .005)
• No statistically significant between-group differences were observed in durations of intubation, intensive care unit stay, and hospital stay; mortality; and frequency and severity of adverse events
  

Conclusion: Patients receiving a silver-coated endotracheal tube had a statistically significant reduction in the incidence of VAP and delayed time to VAP occurrence compared with those receiving a similar, uncoated tube.


Silver-Coated Endotracheal Tubes and Incidence of Ventilator-Associated Pneumonia JAMA. 2008;300(7):805-813.

Monday February 1, 2010


Q: In treatment of increase Intracranial pressure (ICP), what is the equivalency of 23.4% of NaCl and Mannitol in terms of similar effect?

Answer: To be precise, 0.686 ml of 23.4% of NaCl is equiosmolar to 1 gram of mannitol in effect. Usual dose is 30-50 ml of 23.4% of NaCl q3-q6 hours as needed.