Sunday, January 31, 2010
Q: What is Osler-Weber-Rendu syndrome?
Answer: Osler-Weber-Rendu syndrome is an inherited condition. People with this condition develop abnormal blood vessels called arteriovenous malformations (AVMs) in several areas of the body. If they are on the skin, they are called telangiectasias. The AVMs can also develop in other areas of the body, such as the brain, lungs, liver, or intestines.
Saturday, January 30, 2010
Weekend vs Weekday Stroke
Objective: To determine whether there is a difference in the quality or aggressiveness of care for patients experiencing acute ischemic stroke (AIS) on weekends vs weekdays.
Patients : Its a retrospective study of patients with AIS
Main Outcome Measures: Treatment with tissue plasminogen activator and in-hospital mortality.
- Patients with AIS admitted on weekends are more likely to receive tissue plasminogen activator than those admitted on weekdays
- No statistically significant difference was noted in patient mortality based on day of admission
- We detected no difference in the likelihood to seek hospital care on weekends between patients with AIS vs patients with hemorrhagic stroke.
Conclusions: Patients experiencing AIS are more likely to receive tissue plasminogen activator on weekends than on weekdays. Patients experiencing AIS who are admitted on weekends are no more likely to die than those who are admitted on weekdays. Further research is necessary to understand differences in weekend vs weekday care.
Hospital Care for Patients Experiencing Weekend vs Weekday Stroke - Arch Neurol. 2010;67(1):39-44.
Friday, January 29, 2010
Magnesium Sulfate Decreases Cerebral Perfusion Pressure in Preeclampsia
Objective: To determine the cerebral hemodynamic effect of magnesium sulfate (MgSO4) in preeclampsia.
Design: Prospective observational study in Preeclamptic patients.
Methods: Transcranial Doppler (TCD) of the middle cerebral arteries (MCA) of 15 preeclamptics, before and after IV MgSO4. No vasoactive drugs other than MgSO4 were given.
- 11 patients with mild range BP (140/90 - 160/110 mmHg) had measurements at baseline, 30 and 120 minutes after MgSO4, and
- 7 patients with elevated CPP had baseline and 30 minute measurements.
Main Outcome Measures: Mean arterial pressure (MAP), heart rate (HR), cerebral perfusion pressure (CPP), resistance index (RI), resistance area product (RAP), and cerebral flow index (CFI).
Results: Eight women had normal baseline CPP, and 11 had normal CFI.
- 11 had mild preeclampsia range blood pressure and MgSO4 had no significant effect on CPP, CFI, HR, MCA velocities, or RAP but did decrease the MAP in the first 30 minutes mainly due to a drop in diastolic pressure
- 7 patients with elevated baseline CPP had a significant reduction in CPP, but no change in CFI, after MgSO4
Magnesium Sulfate Decreases Cerebral Perfusion Pressure in Preeclampsia - Hypertension in Pregnancy, Volume 27, Issue 4, November 2008 , pages 315 - 327
Thursday, January 28, 2010
Q: 52 year old male developed intracranial hemorrhage after receiving thrombolytic therapy for CVA. What is the treatment?
Answer: Transfusion of cryoprecipitate.
Prepare for administration of 6 to 8 units of cryoprecipitate containing factor VIII. It is not a bad idea to also adminster 6 to 8 units of platelets.
Wednesday, January 27, 2010
On J Point
The J point represents the end of depolarization and the beginning of repolarization as determined by the surface ECG. The term J deflection has been used to designate the formation of the wave produced when there is a large, prominent deviation of the J point from the baseline. The J deflection has been called many names, including camel-hump sign, late delta wave, J-point wave, and Osborn wave.
Beside hypothermia some other causes of J deflection are
- brain injury,
- subarachnoid hemorrhage,
- damage to sympathetic nerves in the neck, and
- cardiopulmonary arrest from oversedation
All J-wave deflections do not look alike. Some are merely elevations of ST segments in leads V1 and V2, whereas others are of the spike-and-dome variety. This leads to the conclusion that different mechanisms may be responsible for the size and shape of J-wave deflections.
*The prominent J deflection attributed to hypothermia was first reported in 1938 by Tomaszewski but the unusual wave increasingly has been called an Osborn wave after Osborn's article written in 1953
Tuesday, January 26, 2010
Ice test in Myasthenia Gravis
Most of the Myasthenia patients along with other symptoms of weakness usually exhibits ptosis. While at bedside place an ice cube over eye lids for 2 minutes. Cooling improves neuromuscular transmission. Resolution of ptosis with cooling is a positive test for Myasthenia Gravis and reported upto 80% reliable to diagnose ocular myasthenia.
Monday, January 25, 2010
Q: In Salicylate toxicity what is the target of Urine PH?
Renal elimination of salicylate can be achieved by alkaline diuresis to increase urine pH, ideally to more than/= 8. Alkaline diuresis is indicated for patients with any symptoms of poisoning and should not be delayed until salicylate levels are determined. This intervention is safe and exponentially increases salicylate excretion. Because hypokalemia may interfere with alkaline diuresis, patients are given a solution consisting of 1 L of 5% D/W, with 3 (50-mEq) ampules of NaHCO3, and 40 mEq of KCl. Serum K should be monitored closely.
Sunday, January 24, 2010
Fluid Management in Acute Lung Injury Secondary to Septic Shock - A tricky business
Background: Recent studies have suggested that early goal-directed resuscitation of patients with septic shock and conservative fluid management of patients with acute lung injury (ALI) can improve outcomes. Because these may be seen as potentially conflicting practices, we set out to determine the influence of fluid management on the outcomes of patients with septic shock complicated by ALI.
Methods: A retrospective analysis was performed at Barnes-Jewish Hospital (St. Louis, MO) and in the medical ICU of Mayo Medical Center (Rochester, MN). Patients hospitalized with septic shock were enrolled into the study if they met the American-European Consensus definition of ALI within 72 h of septic shock onset.
- Adequate initial fluid resuscitation (AIFR) was defined as the administration of an initial fluid bolus of more than/= 20 mL/kg prior to and achievement of a central venous pressure of more than/= 8 mm Hg within 6 h after the onset of therapy with vasopressors.
- Conservative late fluid management (CLFM) was defined as even-to-negative fluid balance measured on at least 2 consecutive days during the first 7 days after septic shock onset.
Results: The study cohort was made up of 212 patients with ALI complicating septic shock.
- Hospital mortality was statistically lowest for those achieving both AIFR and CLFM and higher for those achieving only CLFM, those achieving only AIFR, and those achieving neither.
The Importance of Fluid Management in Acute Lung Injury Secondary to Septic Shock - CHEST July 2009 vol. 136 no. 1 102-109
Saturday, January 23, 2010
Q: Can you use diuretics in DI (Diabetes Insipidus)?
Answer: yes - you can use Hydrochlorothiazide.
Thiazide diuretic decreases urinary volume in absence of ADH. It may induce mild volume depletion and cause proximal salt and water retention, thereby reducing flow to the ADH-sensitive distal nephron. Effects are additive to other agents.
Friday, January 22, 2010
If CT scan shows a mass which has air containing bronchi (arrows) within it. Differential diagnosis includes
- sarcoidosis (highly suspicious)
- bronchioloalveolar carcinoma,
- lymphoma, and
Thursday, January 21, 2010
Q: 34 year old male patient had LP (lumbar punture) 4 days ago but continue to complaint of severe headache. Analgesics are not working. What would be other simple recommendation?
Answer: Caffeine - 300-500 mg q4-6h
In severe cases Caffeine sodium benzoate (500 mg) in 1 liter of fluid (D5LR) can be given intravenously over one and a half hour. The patients usually have complete resolution of symptoms and no recurrence of headache.
Caffeine sodium benzoate is a simple treatment of post-lumbar-puncture headaches. It should be considered as a safe alternative to an epidural blood patch for the treatment of post-lumbar-puncture headaches.
A simple treatment of post-lumbar-puncture headache. - J Emerg Med. 1989 Jan-Feb;7(1):29-31.
Wednesday, January 20, 2010
Answer: CNS toxoplasmosis.
A CT scan shows a ring-enhancing lesion with an eccentric nodule, which also enhances. The corticomedullary location and marked surrounding edema are characteristic of toxoplasmosis.
Tuesday, January 19, 2010
Q: 28 year old male is recently started on Isoniazide (INH) after he was tested postive for PPD during routine employment exam. He is now admitted with seizure. What is the treatment?
Answer: IV Pyridoxine (Vitamin B6)
Five grams of IV pyridoxine given over 5-10 minutes is sufficient to abolish the neurologic effects of isoniazid in most cases. Repeat dosing may be required for persistent seizure activity. Patients usually do not respond to most of the antiepileptics.
Monday, January 18, 2010
Q: The Claviprex (clevidipine butyrate) is a newly approved IV medication for acute hypertension control as a continuous infusion. It is relatively contraindicated in patients with?
A) Allergies to soybeans, soy products, eggs, or egg products;
B) Defective lipid metabolism such as pathologic hyperlipemia, lipoid nephrosis,
C) Acute pancreatitis if it is accompanied by hyperlipidemia;
D) Severe aortic stenosis.
E) All of the above
It is a lipid based drug. It is almost look alike Propofol at bedside (care should be taken in titrating due to accidental confusion). It contains phospholipids and can support microbial growth. Once the stopper is punctured, it should be use and discarded within 4 hours.
It has an extremely short half life of 90 seconds and desirable for close titration of hypertension.
Sunday, January 17, 2010
Volume of Pleural Fluid Required To Diagnose Malignancy
Background: The optimal volume of pleural fluid to diagnose a malignant effusion is unknown. Our study was designed to demonstrate if a minimum pleural fluid volume (10 mL) is equivalent to a large volume thoracentesis to make a cytopathologic diagnosis of malignancy.
Methods: A total of 121 thoracentesis samples were obtained from 102 patients with suspected or known malignant effusions. Pleural fluid was collected in three aliquots for cytologic examination
- 10 mL,
- 60 mL,
- More than/= 150 mL
The pathologist was blinded to patient identifiers and aliquot volume. Sensitivity, specificity, negative predictive value (NPV), and positive predictive value (PPV) were calculated for each volume for the diagnosis of malignancy.
Results: Pleural malignancy was diagnosed in 90 patient encounters (74.4%).
- For direct smear/cytospin, there was increased sensitivity and NPV for 60 mL and for 150 mL compared with 10 mL.
- For combined direct smear/cytospin and cell block preparations, statistical significance for sensitivity and NPV existed only between the 10 mL and 150 mL specimens.
- No statistical difference existed for specificity or PPV for any aliquot volume.
Prospective Study To Determine the Volume of Pleural Fluid Required To Diagnose Malignancy - CHEST January 2010 vol. 137 no. 1 68-73
Saturday, January 16, 2010
Q: What is the ratio of alpha and beta blockade in Labetalol?
A: As an anti-hypertensive, Labetalol has both alpha-blockade and beta-blockade activity. The ratio of alpha to beta blockade activity is
- 1:3 when used orally
- 1:7 when used intravenously
Friday, January 15, 2010
Q: Roth spots (see picture below) - Do they interfere with vision?
These "white-centered" hemorrhages are not specific for bacterial endocarditis. They probably reflect microinfarcts and occur in essential hypertension, HIV, connective tissue disease, severe anemia, Behçet's disease, viremia, and hypercoagulable states.
They do not interfere with vision.
Thursday, January 14, 2010
ICP (Intracranial pressure) wave forms
ICP monitoring waveform has a flow of 3 upstrokes in one wave.
- P1 = (percussion wave) represents arterial pulsation
- P2 = (Tidal wave) represents intracranial compliance
- P3 = (Dicrotic wave) represents aortic valve closure
In normal ICP waveform P1 should have highest upstroke, P2 in between and P3 should show lowest upstroke.
On eyeballing the monitor, if P2 is higher than P1 - it indicates intracranial hypertension.
Extra reading: click to abstract
Monitoring and interpretation of intracranial pressure - Journal of Neurology Neurosurgery and Psychiatry 2004;75:813-821
Wednesday, January 13, 2010
Q: Which of the following drugs has strong anti-emetic property?
D) Haldol (Haloperidol)
E) Zantac (Ranitidine)
The peripheral antidopaminergic effects of haloperidol account for its strong antiemetic activity. There, it acts at the chemoreceptor trigger zone (CTZ). Haloperidol is useful to treat severe forms of nausea/emesis such as those resulting from chemotherapy. The peripheral effects lead also to a relaxation of the gastric sphincter muscle.
None of the other drugs has anti-emetic property.
Tuesday, January 12, 2010
Q: Adenosine can cause
B) Atrial fibrillation
C) Ventricular fibrillation
D) All of the above
Certain SVTs can be successfully terminated with adenosine. This includes any re-entrant arrhythmias - AV reentrant tachycardia(AVRT), AV nodal reentrant tachycardia (AVNRT) - by causing transient heart block in the AV Node. This is mediated via the A1 receptor, inhibiting adenylyl cyclase, reducing cAMP and so causing cell hyperpolarization by increasing outward K+ flux.
Adenosine has an indirect effect on atrial tissue causing a shortening of the refractory period and may initiate atrial fibrillation. In individuals with accessory pathways, the onset of atrial fibrillation can lead to a life-threatening ventricular fibrillation.
Monday, January 11, 2010
A note on Terlipressin
Terlipressin is an analogue of vasopressin with longer half life. Over the past few years there has been much interest in the use of terlipressin both in adults and children. Vasopressin mediates vasoconstriction via V1 receptors and increases intracellular calcium concentration. Terlipressin (triglycyl lysine vasopressin) is a long-acting vasopressin analog. In part, it is a prodrug that is slowly cleaved in vivo to lysine vasopressin by endo- and exopeptidases in the liver and kidney over 4-6 hrs, thereby allowing prolonged effects by intermittent intravenous injections rather than continuous intravenous infusion.
Terlipressin is administered as a single bolus of 1 mg (the dosage used in gastroenterological indications) in patients with septic shock refractory to catecholamine/hydrocortisone/methylene blue. A significant improvement in blood pressure can be seen during the first 5 hours. Partial or total weaning from catecholamines is possible.
Terlipressin (1 or 2 mg intravenously) is able to reverse the intractable hypotension, with a concomitant decrease in heart rate and CI. With Terlipressin renal function and gastric mucosal perfusion are improved.
One serious concern is raised by the high incidence of ischaemia during terlipressin administration (skin and/or limb ischaemia).
In conclusion, use of terlipressin may be considered in patients with (truly) refractory septic shock despite adequate fluid resuscitation and high-dose conventional vasopressors.
Sunday, January 10, 2010
Googling Ourselves — What Physicians Can Learn from Online Rating Sites
"......My patients often Google a medication I've recommended or a disease I've diagnosed, despite the fact that I give them medication data sheets and patient education pamphlets. I figure it is not inconceivable that they would Google me too, and I'm curious to see what they will find.....
I anxiously scan the first 10 results, which offer a variety of promises to provide the reader with priceless information about Shaili Jain, M.D.: "free doctor profile report," "check her ratings and credentials," "detailed background report," "comparisons with physicians in similar specialties." Then my anxiety turns to fear as I find what I was looking for: patients' ratings of me on the many online physician-rating sites.
These sites, such as RateMDs, Vimo, and RevolutionHealth, offer patients an opportunity to rate physicians on their helpfulness, knowledge base, interpersonal skills, and punctuality..... Critics find the sites defamatory and fundamentally flawed. How can one be sure the person posting a review is really a patient and not someone with a grudge against the physician? If a physician disagrees with a particular comment, there is no opportunity for rebuttal: physicians are bound by privacy laws and a duty to preserve the confidentiality of patient information. Also, most rated physicians average a handful of ratings, which can hardly reflect the full range of impressions of a physician who sees hundreds of patients each year....
I find one score for me on Vitals.com — a pathetic 2.5 out of 5 — but I don't see any comments and can't figure out whether this is an aggregate score. It looks as if I have to pay for further information, so I scan the results for my colleagues. Most are not rated, some got 1 out of 5, and one got 4 out of 5. I exit the site, deciding its offerings are not meaningful. A few more minutes of surfing reveals that my Internet reputation is intact. I am relieved.
As I log off and prepare for a day of doctoring, I realize that despite the anxiety it has provoked since medical school, I should adapt to having my scores available for public inspection — it will clearly continue to be a fact of my professional life. Whether publicly available performance evaluations will actually result in better care and service for patients or just more bureaucracy and wasted energy remains to be seen."
Read full article from Shaili Jain, M.D. at The New England Journal of Medicine (january 7, 2010) here
Saturday, January 9, 2010
Central Venous Access on Same Side of Hemothorax
A 25-yr-old man is admitted to the emergency room after motor vehicle accident on new year night. CXR showed a right-sided hemothorax. You inserted right chest tube draining 2 litres of blood. Thinking as chest tube is already placed you inserted subclavian vein central line on same side (right) with good return on all 3 ports. You started volume resuscitation. Repeat CXR shows full resolution of the hemothorax and central line in lower SVC. Despite continuous volume replacement with multiple pRBCs and 4 liters of LR and colloid blood pressure continues to deteriorate and increased drainage of blood from the chest tube noted. For faster resuscitation you placed large bore (cordis) line in left femoral vein. More volume is given through the new femoral line and patient seems to stabilize. Repeat CXR showed reaccumulation of hemothorax. Patient taken to OR but found to have a diagnosis of laceration of major vessel due to central line placement instead of original trauma. New left IJ line placed and patient stabalized.
Friday, January 8, 2010
Electronic ICU - does it work?
Objective: To determine the impact of a telemedicine system, the electronic intensive care unit (eICU), on ICU, and non-ICU mortality, total mortality, total and ICU-specific length of stay, and total hospital cost at two community hospitals.
Design: Observational study with one baseline period and two comparison periods (eICU wave one and eICU wave two). Each time period was 4 months in duration.
Setting: Four ICU from two community hospitals in the metropolitan Chicago area. Hospital one is a 610-bed teaching hospital with three adult ICU (ten-bed medical ICU, ten-bed cardiac ICU, and 14-bed surgical ICU). Hospital two is a 185-bed nonteaching hospital with a ten-bed mixed medical/surgical ICU.
Patients: All patients 18 yrs or older with an ICU stay of at least 4 hrs during the specified time period were included.
Interventions: The eICU was implemented at both hospitals in April 2003.
Measurements and Main Results: Mortality, length of stay, and total cost were measured. Age, gender, race/ethnicity, trauma status, Acute Physiology and Chronic Health Evaluation III score, and physician utilization of the eICU were included as covariates. Included in the analysis were 4088 patients (1371 at baseline, 1287 in eICU wave one, and 1430 in eICU wave two).
- The eICU did not have a significant effect on ICU/non-ICU/total mortality or hospital length of stay.
- ICU length of stay increased over time and was associated with higher physician utilization of the eICU.
- Although total hospital costs increased over time, the rate of increase was steeper for those patients whose physicians permitted only a low level of eICU involvement.
Clinical and economic outcomes of the electronic intensive care unit: Results from two community hospitals - Critical Care Medicine: January 2010 - Volume 38 - Issue 1 - pp 2-8
Thursday, January 7, 2010
A note on hyperkalemic response after succinylcholine administration
Not all patients have an exaggerated hyperkalemic response after succinylcholine administration. However, patients with conditions involving central and peripheral motor neurons, such as encephalitis, stroke, intracranial tumors, cerebral aneurysms, head trauma, spinal cord injuries, Guillain-Barré syndrome, and myopathies, may develop severe hyperkalemia after succinylcholine administration. Hyperkalemia has also been observed during the prolonged immobility of patients with burns or intraabdominal infections and in patients receiving other nondepolarizing neuromuscular blocking agents. Also, preexisting hyperkalemia may be exacerbated in patients with chronic renal insufficiency.
Wednesday, January 6, 2010
Omentum in the management of complex cardiothoracic surgical problems
Vascularized, pedicled tissue flaps are often used for cardiothoracic surgical problems complicated by factors that adversely affect healing, such as previous irradiation, established infection, or steroid use. Use of omentum was prophylactic to aid in the healing of closures or anastomoses considered to be at high risk for failure. Overall, omental transposition is successful in its prophylactic or therapeutic purpose. Complications of omental mobilization are rare. Omentum's unique properties render it an excellent choice of vascularized pedicle in the management of the most complex cardiothoracic surgical problems.
Omentum is highly effective in the management of complex cardiothoracic surgical problems. J Thorac Cardiovasc Surg. 2003 Mar;125(3):526-32.
Tuesday, January 5, 2010
Emerging literature in Critical Care nutrition shows that Glutamine supplement improves survival from Multi Organ Failure. Low plasma glutamine has been shown to be an independent predictive factor for a poor outcome.
Glutamine is linked to improved immune function and fewer infections.Glutamine is a dietary non-essential amino acid, however during situations of extreme stress a deficiency develops. Ideally, it needs 20-40 gram glutamine per day to restore plasma glutamine levels to normal.
A major demand for glutamine via glutamate is for the production of the major cellular anti-oxidant glutathione. Low intramuscular glutathione levels are correlated with low glutamine and glutamate levels in the critically ill patients. Glutamine has been shown protective to intestinal cells. Patients with severe burns, who were nevertheless fed enterally, showed a significant reduction in septicemia.
Delivery of 30 g/day of glutamine jejunally in multiple-trauma patients led to a significant reduction in pneumonia, bacteraemia, and severe sepsis.
Practically, Glutamine (GlutaSolve) can be given via enteral route 1 packet (15 gram) twice a day after mixing in 100 cc of water.
Contraindications are acute renal failure without dialysis and moderate to severe hepatic failure.
Reference: Click to get article
Glutamine in the critically ill , Richard D Griffiths, Professor of Medicine (Intensive Care), University of Liverpool, UK. , lecture in Paris, June 9-10, 2005 - pdf file
Monday, January 4, 2010
Trivia on Urokinase
Urokinase is a physiologic thrombolytic agent that is produced in renal parenchymal cells. Unlike streptokinase, urokinase directly cleaves plasminogen to produce plasmin. When purified from human urine, approximately 1500 L of urine are needed to yield enough urokinase to treat a single patient.
In plasma, urokinase has a half-life of approximately 15 minutes. Allergic reactions are rare, and the agent can be administered repeatedly without antigenic problems.
Urokinase is also commercially available in a form produced by tissue culture, and recombinant DNA techniques have been developed for urokinase production in E coli cultures.