Wednesday July 11, 2007
Iodide in Thyroid Storm
Q; How long should you wait to administer iodide after giving antithyroid medication in the management of thyroid storm ?
A; Atleast one hour.Oral or rectal iodide compounds block release of thyroid hormones after starting antithyroid drug therapy. But if given early in management (before antithyroid medication become effective) it can get utilize in the synthesis of new thyroid hormone.
Read nicely written review on Thyroid Storm (and Myxedema coma) by Nikolaos Stathatos, MD, and Leonard Wartofsky, MD from Washington Hospital Center in Washington, D.C. - ref.: emedmag.com, 02/15/2003 issue.
Wednesday, July 11, 2007
Tuesday, July 10, 2007
Tuesday July 10, 2007
Gadolinium based contrast agent (GBCA) and renal insufficiency
During MRI and MRA scans, a Gadolinium based contrast agent (GBCA) is used for more refined films. New evidences suggest that Gadolinium based contrast agents are associated with Nephrogenic Systemic Fibrosis (NSF) or Nephrogenic Fibrosing Dermopathy (NFD). Interestingly, the effect may be delayed upto 18 months after exposure !!
NSF may result in fatal or debilitating systemic fibrosis affecting the skin, muscle, and internal organs. Patients with renal dysfunction are at very high risk for NSF. In dialysis dependent patients, it is recommended to consider prompt hemodialysis following GBCA administration and upto 3 frequent sessions of dialysis. (Does it work ?). NSF is well documented following exposure to a GBCA in patients with
- acute or chronic severe renal insufficiency (GFR less than 30) *
- patients with acute renal insufficiency of any severity due to the hepato-renal syndrome or
- in the peri-operative liver transplantation period
*To date, there has not been a report of NSF in a patient with normal renal function or mild to moderate renal insufficiency following GBCA exposure
Among the factors that may increase the risk for NSF are repeated or higher than recommended doses of a GBCA. The dose of gadolinium-based contrast agent given to patients undergoing an MRA is often higher and have higher risk of developing the condition.
The signs and symptoms of NSF includes itching, reddened or darkened patches on skin; and/or skin swelling, hardening and/or tightening. Yellow raised spots on the whites of the eyes. Joint stiffness and/or muscle weakness. In addition, patients may develop widespread fibrosis of other organs. A skin biopsy is necessary to confirm the diagnosis.
There is no treatment for NSF.
FDA has recently advised detailed box warning which can be read here.
Monday, July 9, 2007
Monday July 09, 2007
Male vs Female blood product transfusion (Plasma and apheresis platelets) !
Interesting study published in July 2007 issue of Critical Care Medicine 1 comparing transfusion from male-only versus female donors.
In this retrospective case-control study, 112 patients who received high plasma volume components (more than 2 units of fresh frozen plasma or apheresis platelets) from male-only donors were identified and compared them with from female donors. - patients matched by severity of illness, postoperative state, and number of transfusions. Baseline characteristics, ALI risk factors, and development of ALI were similar between the two groups.
Results:
Study concluded that in critically ill recipients of high plasma volume components, gas exchange worsened significantly after transfusion of female but not male donor components.
Reference: Click to get article/abstract
Transfusion from male-only versus female donors in critically ill recipients of high plasma volume components - Critical Care Medicine. 35(7):1645-1648, July 2007.
Few Previous Related Pearls:
FFP and platelet transfusion may be associated more with ALI/ARDS than pRBC transfusion
Why we call it cryoprecipitate?
How much FFP?
Male vs Female blood product transfusion (Plasma and apheresis platelets) !
Interesting study published in July 2007 issue of Critical Care Medicine 1 comparing transfusion from male-only versus female donors.
In this retrospective case-control study, 112 patients who received high plasma volume components (more than 2 units of fresh frozen plasma or apheresis platelets) from male-only donors were identified and compared them with from female donors. - patients matched by severity of illness, postoperative state, and number of transfusions. Baseline characteristics, ALI risk factors, and development of ALI were similar between the two groups.
Results:
- Arterial oxygenation (Pao2/Fio2) worsened after the female (p = .008) but not after male-only donor product transfusion (p = .325).
- Male-only component recipients had more ventilator-free days (median 28 vs. 27, p = .006) and
- a trend toward lower hospital mortality rates (14% vs. 24%, p = .054).
- no significant difference in development of ALI after transfusion.
Study concluded that in critically ill recipients of high plasma volume components, gas exchange worsened significantly after transfusion of female but not male donor components.
Reference: Click to get article/abstract
Transfusion from male-only versus female donors in critically ill recipients of high plasma volume components - Critical Care Medicine. 35(7):1645-1648, July 2007.
Few Previous Related Pearls:
FFP and platelet transfusion may be associated more with ALI/ARDS than pRBC transfusion
Why we call it cryoprecipitate?
How much FFP?
Sunday, July 8, 2007
Sunday July 08, 2007
iPods may interfere with pacemakers
Orginally reported at Reuters Health by By Megan Rauscher
Apple iPod MP3 music players may interfere with the functioning of implanted pacemakers, according to research reported at the Heart Rhythm Society's 28th annual scientific sessions in Denver, Colorado few weeks ago.
...............In their study, Dr. Krit Jongnarangsin of the University of Michigan, Ann Arbor and colleagues looked at the effect of four different iPod models (third generation, photo, video and Nano iPods) on implantable pacemaker function in 100 patients. A technician monitored intracardiac electrograms and a surface ECG while each iPod was held near the chest for 5 to 10 seconds in the on and off position.
The iPods, when held two inches from the patients' chest and as far as 18 inches, "interfered with pacemaker function in about one third of patients," Dr. Jongnarangsin noted in a telephone interview with Reuters Health. Pacemaker oversensing -- defined as spurious atrial/ventricular sensed events on the marker channel associated with atrial/ventricular inhibition, mode switching or high atrial/ventricular rates on rate histograms - was seen in 19% of patients.
Telemetry interference -- defined as any other interference that did not affect pacing function and was not detected by pacemaker interrogation -- occurred in 32%, and pacemaker inhibition in 1%. Oversensing and telemetry interference occurred more often with third generation iPods and the photo iPod than with the video and Nano iPod.
The observed iPod interference did not cause any clinical symptoms. "However, in one patient the iPod transiently inhibited pacemaker function," Dr. Jongnarangsin pointed out.
There is a concern, he added, that iPod interference might lead to an incorrect diagnosis of abnormal heart rhythm. "If we don't take into account that the patient has an iPod close to the pacemaker, we may assume that the patient has an abnormal heart rate rhythm," Dr. Jongnarangsin said.
"We need more information and more studies on iPod interference in pacemaker function," he concluded.
iPods may interfere with pacemakers
Orginally reported at Reuters Health by By Megan Rauscher
Apple iPod MP3 music players may interfere with the functioning of implanted pacemakers, according to research reported at the Heart Rhythm Society's 28th annual scientific sessions in Denver, Colorado few weeks ago.
...............In their study, Dr. Krit Jongnarangsin of the University of Michigan, Ann Arbor and colleagues looked at the effect of four different iPod models (third generation, photo, video and Nano iPods) on implantable pacemaker function in 100 patients. A technician monitored intracardiac electrograms and a surface ECG while each iPod was held near the chest for 5 to 10 seconds in the on and off position.
The iPods, when held two inches from the patients' chest and as far as 18 inches, "interfered with pacemaker function in about one third of patients," Dr. Jongnarangsin noted in a telephone interview with Reuters Health. Pacemaker oversensing -- defined as spurious atrial/ventricular sensed events on the marker channel associated with atrial/ventricular inhibition, mode switching or high atrial/ventricular rates on rate histograms - was seen in 19% of patients.
Telemetry interference -- defined as any other interference that did not affect pacing function and was not detected by pacemaker interrogation -- occurred in 32%, and pacemaker inhibition in 1%. Oversensing and telemetry interference occurred more often with third generation iPods and the photo iPod than with the video and Nano iPod.
The observed iPod interference did not cause any clinical symptoms. "However, in one patient the iPod transiently inhibited pacemaker function," Dr. Jongnarangsin pointed out.
There is a concern, he added, that iPod interference might lead to an incorrect diagnosis of abnormal heart rhythm. "If we don't take into account that the patient has an iPod close to the pacemaker, we may assume that the patient has an abnormal heart rate rhythm," Dr. Jongnarangsin said.
"We need more information and more studies on iPod interference in pacemaker function," he concluded.
Friday, July 6, 2007
Friday July 06, 2007
Treating cocaine induced hypertension
Cocaine induced hypertension is due to alpha-mediated vasoconstriction. Beta-blockers are advised to be avoided in the setting of cocaine toxicity because they may result in unopposed alpha effects of cocaine and may further increase the blood pressure. There are also some reports of seizures with B-blocker is such situation.
Calcium channel blockers dilate splanchnic vessels and thereby increasing absorption of ingested cocaine from the gastrointestinal tract, which may become disastrous in body packers. Nifedipine is also reported to potentiate the incidence of seizures and death after cocaine administration and should be avoided in the treatment of cocaine-induced hypertension.
Benzodiazepines is the first line of treatment in cocaine-induced hypertension. And if benzodiazepines fail to control hypertension, vasodilators, as nitroprusside and nitroglycerin should be use. And if vasodilators doesn't works, alpha-blockers, such as phentolamine is the next choice.
Treating cocaine induced hypertension
Cocaine induced hypertension is due to alpha-mediated vasoconstriction. Beta-blockers are advised to be avoided in the setting of cocaine toxicity because they may result in unopposed alpha effects of cocaine and may further increase the blood pressure. There are also some reports of seizures with B-blocker is such situation.
Calcium channel blockers dilate splanchnic vessels and thereby increasing absorption of ingested cocaine from the gastrointestinal tract, which may become disastrous in body packers. Nifedipine is also reported to potentiate the incidence of seizures and death after cocaine administration and should be avoided in the treatment of cocaine-induced hypertension.
Benzodiazepines is the first line of treatment in cocaine-induced hypertension. And if benzodiazepines fail to control hypertension, vasodilators, as nitroprusside and nitroglycerin should be use. And if vasodilators doesn't works, alpha-blockers, such as phentolamine is the next choice.
Thursday, July 5, 2007
Thursday July 05, 2007
Increased risk of severe protamine reactions in NPH dependent diabetics and with fish allergy
Protamine is a commonly used reversal for systemic heparinization after cardiac procedures. Protamine is well known for its relatively rare but severe anaphylaxis.
Patients using NPH are more prone to such reactions and caution should be exercise in such patients. Because NPH as stands for Neutral Protamine Hagedorn contains protamine, it is suspected that NPH insulin-dependent diabetic patients would develop sensitivity to protamine 1.
Similarly, people allergic to fish are also prone to protamine reaction as afterall protamine comes from sperm of salmon fish ! 2
Beside standard preacution (giving diluted and slowly) and treatment of anaphylaxis, methylene blue has been proposed as the treatment of protamine reaction 3.
References: click to get abstracts/articles
1. Increased risk of severe protamine reactions in NPH insulin-dependent diabetics undergoing cardiac catheterization, Circulation, Vol 70, 788-792
2. PHYSICAL AND CHEMICAL PROPERTIES OF PROTAMINE FROM THE SPERM OF SALMON (ONCORHYNCHUS TSCHAWYTSCHA) - Paper originally published in 1957, source - Journal of Biological Chemistry
3. Catastrophic Cardiovascular Adverse Reactions to Protamine Are Nitric Oxide/Cyclic Guanosine Monophosphate Dependent and Endothelium Mediated Should Methylene Blue Be the Treatment of Choice? - Chest. 2002;122:1061-1066.
Increased risk of severe protamine reactions in NPH dependent diabetics and with fish allergy
Protamine is a commonly used reversal for systemic heparinization after cardiac procedures. Protamine is well known for its relatively rare but severe anaphylaxis.
Patients using NPH are more prone to such reactions and caution should be exercise in such patients. Because NPH as stands for Neutral Protamine Hagedorn contains protamine, it is suspected that NPH insulin-dependent diabetic patients would develop sensitivity to protamine 1.
Similarly, people allergic to fish are also prone to protamine reaction as afterall protamine comes from sperm of salmon fish ! 2
Beside standard preacution (giving diluted and slowly) and treatment of anaphylaxis, methylene blue has been proposed as the treatment of protamine reaction 3.
References: click to get abstracts/articles
1. Increased risk of severe protamine reactions in NPH insulin-dependent diabetics undergoing cardiac catheterization, Circulation, Vol 70, 788-792
2. PHYSICAL AND CHEMICAL PROPERTIES OF PROTAMINE FROM THE SPERM OF SALMON (ONCORHYNCHUS TSCHAWYTSCHA) - Paper originally published in 1957, source - Journal of Biological Chemistry
3. Catastrophic Cardiovascular Adverse Reactions to Protamine Are Nitric Oxide/Cyclic Guanosine Monophosphate Dependent and Endothelium Mediated Should Methylene Blue Be the Treatment of Choice? - Chest. 2002;122:1061-1066.
Wednesday, July 4, 2007
"Health care in the United States"
Wednesday July 04, 2007
Happy Birthday America
Today we selected following read on "Health care in the United States"
"The debate about U.S. health care concerns questions of access, efficiency, and quality purchased by the high sums spent. The overall performance of the United States health care system was ranked 37th by the World Health Organization (WHO) in 2000, but the same report assessed Americans' overall health at 72nd among 191 member nations included in the study.However, most Americans rate their own health as "excellent" or "very good". The National Health Interview Survey, released annually by the Centers for Disease Control's National Center for Health Statisticsreported that approximately 66% of survey respondents said they were in "excellent" or "very good" health in 2006. This percentage has been declining since 1998"
"Most Americans, 59.5%, receive their health insurance coverage through an employer, and about 9% purchase it directly from the market.Government sources cover 27.3% of the population (80.2 million).In 2005, there were 46.6 million people in the U.S. (15.9% of the population) who were without health insurance for at least part of that year. Among the uninsured, nearly 37 million were employment-age adults (ages 18 to 64), and more than 26 million worked at least part time. Approximately a quarter of the uninsured live in households with an income over $50,000.It is has been estimated that nearly one fifth of the uninsured population is able to afford insurance, almost one quarter is eligible for public coverage, and that the remaining 56% need financial assistance (8.9% of all Americans)".
you can have the full read here (source: wikipedia.org)
Tuesday, July 3, 2007
Subarachnoid Hemorrhage - CT scan representation
Tuesday July 03, 2007
Subarachnoid Hemorrhage - CT scan representation
Subarachnoid hemorrhage occurs when a blood vessel just outside the brain ruptures. The area of the skull surrounding the brain, call the subarachnoid space rapidly fills with blood. Sometimes this is described as the worst headache of one's life.
Nice Review article on Subarachnoid Hemorrhage from emedicine.com
Subarachnoid Hemorrhage - CT scan representation
Subarachnoid hemorrhage occurs when a blood vessel just outside the brain ruptures. The area of the skull surrounding the brain, call the subarachnoid space rapidly fills with blood. Sometimes this is described as the worst headache of one's life.
Nice Review article on Subarachnoid Hemorrhage from emedicine.com
Monday, July 2, 2007
Monday July 02, 2007
PFO
Scenario: 88 year old female admitted to hospital after Non-Q wave MI. Patient required intubation during cardiac catheterization due to oversedation but pre procedure ABG was normal. Patient continue to have refractory hypoxemia. Workup for PE is negative with essentially normal chest CT. No infiltrates noted either. CXR is essentially normal too. Cardiac index is 2.7. Hpoxemia gets worse as PEEP was increased to counter hypoxemia. There is no auto-PEEP detected. Lactic acid and other workup is normal. Cardiac enzymes are actually improving. Regular Transthoracic Echo is normal. In short, you have a patient with stable labs and hemodynamics but with only refractory hypoxemia getting worse with increasing ventilator pressure.
Answer: Patent foramen ovale causing right to left shunt and worsening due to high right sided pressure from high PEEP. Patent foramen ovale is present in about 15% of the population. It get worse with age, usually from a mean of 3.4 mm in the first decade to 5.8 mm in the 10th decade of life. Any increase pressure on right side of heart may make it worse. Diagnosis can be made by bubble study during echocardiogram.
Bubble (contrast) study: After obtaining visualization of the atrial septum on echocardiography (transthoracic or transesophageal), a bolus of agitated saline is injected intravenously. Microbubbles will appear first in the right atrium. If the bubbles appear in the left atrium within 3 cardiac cycles of their appearance in the right atrium, the test is subjected to be call positive.
Treatment is closure of PFO surgically or by device. Or decreasing right sided pressure by IV nitro, diuresis and decreasing ventilator pressure till permanent solution can be intervened.
PFO
Scenario: 88 year old female admitted to hospital after Non-Q wave MI. Patient required intubation during cardiac catheterization due to oversedation but pre procedure ABG was normal. Patient continue to have refractory hypoxemia. Workup for PE is negative with essentially normal chest CT. No infiltrates noted either. CXR is essentially normal too. Cardiac index is 2.7. Hpoxemia gets worse as PEEP was increased to counter hypoxemia. There is no auto-PEEP detected. Lactic acid and other workup is normal. Cardiac enzymes are actually improving. Regular Transthoracic Echo is normal. In short, you have a patient with stable labs and hemodynamics but with only refractory hypoxemia getting worse with increasing ventilator pressure.
Answer: Patent foramen ovale causing right to left shunt and worsening due to high right sided pressure from high PEEP. Patent foramen ovale is present in about 15% of the population. It get worse with age, usually from a mean of 3.4 mm in the first decade to 5.8 mm in the 10th decade of life. Any increase pressure on right side of heart may make it worse. Diagnosis can be made by bubble study during echocardiogram.
Bubble (contrast) study: After obtaining visualization of the atrial septum on echocardiography (transthoracic or transesophageal), a bolus of agitated saline is injected intravenously. Microbubbles will appear first in the right atrium. If the bubbles appear in the left atrium within 3 cardiac cycles of their appearance in the right atrium, the test is subjected to be call positive.
Treatment is closure of PFO surgically or by device. Or decreasing right sided pressure by IV nitro, diuresis and decreasing ventilator pressure till permanent solution can be intervened.
Sunday, July 1, 2007
Sunday July 01, 2007
OR-Live
On Sundays, we try to go little offbeat and try to provide other resources available on internet. Today our recommended site is
As name implies, it has live webcast and videos from previous webcasts of various surgeries including cardiac surgeries like Mitral valve repair, cardiac catherization procedure with angioplasty and stent placement etc.
The next live webcast will be on July 12, 2007 of closure of PFO (Patent Foramen Ovale) without open heart, using a closure device.
On July 24, 2007, there will be a live webcast on totally thoracoscopic epicardial RF ablation for Atrial Fibrillation.One interesting previous webcast was "Beating Heart Totally Endoscopic Coronary Artery Bypass" using da Vinci robotic assistance. Click here
OR-Live
On Sundays, we try to go little offbeat and try to provide other resources available on internet. Today our recommended site is
As name implies, it has live webcast and videos from previous webcasts of various surgeries including cardiac surgeries like Mitral valve repair, cardiac catherization procedure with angioplasty and stent placement etc.
The next live webcast will be on July 12, 2007 of closure of PFO (Patent Foramen Ovale) without open heart, using a closure device.
On July 24, 2007, there will be a live webcast on totally thoracoscopic epicardial RF ablation for Atrial Fibrillation.One interesting previous webcast was "Beating Heart Totally Endoscopic Coronary Artery Bypass" using da Vinci robotic assistance. Click here
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