Tuesday, December 8, 2009
Graves' Disease
Here is a NEJM review on Graves.
We also discussed anti-NMDA receptor encephalitis - there is a case presentation here. A discussion of paraneoplastic syndromes involving the CNS is posted here.
Thursday, December 3, 2009
Back in Business
Friday, September 11, 2009
Hyponatremia - no it's Hyperhydroemia
1. In patients on diuretics, the fractional excretion of urea can be used to help determine if patient is hypovolemic. FeUrea= (Uurea/Purea)/(UCr/Pcr)
FeUrea <35% suggests prerenal state.
2. Before accusing someone of having SIADH, you must check TSH and adrenal function (ACTH stim).
3. Acute recognition of a chronic problem (chronic hyponatremia) does not require acute treatment.
4. To prevent overly rapid correction of hyponatremia, consider the role for DDAVP (often given as 1-2mcg SC/IV). If you do correct too quickly (want to correct 0.5 mmol/h at the absolute most) also consider giving D5W in addition to DDAVP - see the article below.
5. If volume repletion is required, give fluid that is isotonic to the patient by using a combination of NS and D5W.
6. Attach the foley catheter to the IV (figuratively) - be sure to monitor urine osm and output - and consider calculating a tonicity balance
Extras:
When seeing hyponatremia in the ER:
First rule out acute hyponatremia that needs acute correction.
Recheck the lytes as they were often done a while ago and the patient has possibly received intravenous fluids that may have significantly altered the sodium concentration - especially if the stimulus (often ECF volume depletion) for ADH secretion has been removed. Following the urine output may help to identify this (although recording can be an issue outside of the ICU) as a brisk, dilute diuresis can be bad sign.
An article on DDAVP to prevent rapid correction is posted here.
Wednesday, September 2, 2009
Doctor, There's a Hole in my Heart!?
A prior blog on the causes of platypnea and orthodeoxia can be found here.
Review of PFO formation:
- The endocardial cushions fuse, separating the heart into R and L sides.
- Early in utero the septum primum grows and fuses with the endocardial cushion, closing the formaen primum, however perorations have developed in the septum primum to fuse, forming the foramen secundum (still allowing right to left shunting)
- A second membrane, the septum secundum, grows on the right atrial side of the septum primum. The septum secundum overlaps the foramen secundum, forming an incomplete septal partition that becomes the foramen ovale. The remaining septum primum forms a flap-like valve over the foramen ovale.
- After birth, normal circulation is established (left sided pressures>right sided) and the flap fuses in 75% of people by age 2. The remainder have a PFO.
- The PFO is completed covered, but not sealed and shunting can occur if there is a reversal in intracardiac pressures (i.e. right to left shunt).
- If an open communication exits (no flap) this is an ASD.
A debate on PFO closure (with respect to cryptogenic stroke) can be found in these two Circulation articles: Close v. Don't Close (or at least do an RCT).
SIGNOVER SAFETY
The mneumonic "SIGNOUT?" was developed as part of a signover curriculum discussed in this article.
S - Is the patient sick? Stable? Code Status?
I- ID
G - General Hospital Course
N - New events of the day
O - Overall clinical condition
U - Upcoming possibilities (those that can reasonably anticipated) with plan/rationale
T - Tasks to complete overnight (explicit instructions) and rationale
? - Any questions?
Wednesday, August 19, 2009
Platypnea
After discussing an approach to dyspnea on exertion, the symptom of platypnea was discussed.
Platypnea is an increase in dyspnea in the upright position that improves on lying down.
Orthodeoxia is a decrease in oxygen saturation that occurs upon rising from supine.
These often occur together. They happen when there is right to left shunting that only occurs or is more pronounced, in the upright position. Shunts can be intracardiac (ASD, PFO) or intrapulmnary (AVM, hepatopulmonary syndrome).
This often occurs in HHT, when larger pulmonary AVMs are in bases of the bases of the lungs and therefore recevie a greater proportion of blood when the patient is upright. It can also occur for anatomic reasons in patients with intracardiac shunts.
Shunting can be seen with contrast ECHO where agitated saline bubbles are injected into peripheral veins. They appera in the right heart, and if a right to left shunt exists then they will appear in the left side of the heart. If they appear in 1-2 beats, the shunt is intracaridac, in 3-8 beats then it is likely intrapulmonmary.
Shunt fraction can be calculated by testing SaO2 and PaO2 before and after breating 100% oxygen fro 15 minutes. Normal is less than 5%.
International guidelines for the diagnosis and management of HHT (published by Toronto clinicians) can be found here.
A NEJM review of HHT can be found here.
A NEJM review of hepatopulmonary syndrome can be found here.
Friday, August 14, 2009
Parkinsonism
Here is a link to the JAMA Rational clinical exam article for Parkinson's Disease
Here is a link to a CMAJ review article on Parkinson's disease
When examining someone with potential Parkinsonism (in real life, but also consider if relevant on an exam), be sure to consider the "Parkinson plus" syndromes.
JEOPARDY
Here is a website with some interesting/rare medical conditions - not completely accurate descriptions and genetic causes for many are being discovered. Interesting nevertheless.
Here is the wikipedia page on Ken Jennings, the winningest player in Jeopardy history. He was defeated by Nancy Zerg in his 75th appearance.
Thursday, August 13, 2009
"My, that is a cute joint"
A great advanced discussion today that focused on monoarthritis.
The first step in assessing an "acute joint" is to determine if the process is articular, periarticular or referred.
If it is indeed an acute articular process the differential includes:
- a very good general rule, although as we learned today in classic presentations of other diseases, joint tap may be deferred
Crystal Arthropathy: Gout, Pseudogout (CPPD), Hydroxyapatite
Inflammatory
Seropositive arthritis (early RA or SLE)
Seronegative arthritis (psoriatic, Ankylosing spondilitis, IBD, reactive)
Degenerative: Osteoarthritis
A JAMA rational clinical exam article on septic arthritis is linked here and a CMAJ article on approach to acute monoarthritis is here. Gout is unusual in premenopausal women. An article on acute calcific periarthritis is linked here.
IMAGING
Not always necessary - may be helpful for
1)Trauma
2)Evidence of crystal disease
3)Baseline study (i.e. to follow for development of pathology in future if septic joint, etc.)/to assess for obvious coexisting osteomyelitis.
Antihyperuricemic Treatment
Indications:
Recurrent kidney stones
Gout and renal failure
Tophi
Associate chronic joint changes
Frequent/severe attacks of gout
Options:
Uricosuric agents: - best in uric acid undexcretors (normal urine uric acid with high serum levels). Avoid if renal stones/uric acid nephropathy. Less effective in renal failure.
Xanthine oxidase inhibitor - decrease uric acid synthesis. Good for almost everyone, but need to consider drug interacations and adjusft for comorbidities (renal failure)
- Use minimum dose to achieve effect (follow serum urate levels)
- Azathioprine (Imuran) is mteabolized by xanthine oxidase (decrease Imuran dose by >50% and follow for toxicity)
- Not clear what its role will be vs allopurinol, and ongoing safety monitoring will be important to follow (as with any new med)
CONSIDER prophylaxis with colchicine (0.6 mg up to BID if normal CrCl) when initiating/titrating antihyperuricemic drugs - stop once normouricemic for 6 months.
Tuesday, August 11, 2009
"When I grow up...."
The most important thing is to work hard and do good work - that is how you will build a good reputation.
SEPTOID? What's that?
SEPSIS
Definitions:
SIRS: Two or more of the following: T>38.5°C or <35.0°c;>90 beats/min; RR >20 breaths/min or PaCO2 of <32>12,000 cells/mL, <4000>10 percent immature (band) forms.
Sepsis: SIRS secondary to an infection
MANAGEMENT:
Early goal directed therapy for sepsis is now the standard of care. A trial showing improved mortality using an early goal directed approach to sepsis can be found here, this trial is frequently referred to in the ICU as the Rivers' protocol.
Aimed at maintaining tissue perfusion:
1) Ensure adequate airway/breathing - intubate if necessary. Provide supplemental oxygen
2) Evaluate for signs of poor perfusion - frequent BP monitoring (consider art line - NEJM video on insertion here), LOC, Urine output, lactic acidosis, shock liver, etc.
3) Improve perfusion - FLUIDS!!!!!. Crystalloids (NS or Ringer's) are currently used as the first line resuscitation fluid. Patients often need >6L in the early stages of sepsis - be sure to monitor for signs of fluid overload, especially in those with renal or heart failure. Consider placing a central venous catheter - this provides secure venous access, can allow infusion of inotropes/pressors and can be used to monitor central venous oxygen saturatino and CVP.
4) Monitoring/"Advanced measures" - Involve the ICU/CCRT team. Activated Protein C (Xigris) and/or steroids should be considered in the right clinical context. Steroids are generally used now when shock persists despite adequate fluids and inotrope administration, or in patients on chronic steroids.
5) TREAT THE SOURCE - Identify and treat the cause of infection. In a large retrospective study, antimicrobial administration within the first hour of hypotension was associated with increased survival to hospital discharge in patients with septic shock. Culture potential sources and use appropriate broad spectrum antibiotics based on the suspected source and patient characteristics. Surgical evaluation and debridement should be rapdily arranged if necessary.
Thursday, August 6, 2009
Hypercalcemia - "Milk does a body good?"
Corrected Calcium:
The physiologically important calcium (Ca2+) is ionized calcium. This can be measured in the lab, however, total calcium is the value most commonly reported.
Calcium is bound to serum proteins, most importantly albumin. Therefore, in patients with low serum albumin concentration, the fraction of total serum Ca2+ that exists as ionized Ca2+ will be higher.
It is important to know the serum albumin when interpreting total serum calcium levels. A correction for total serum calcium can be made using the following formula (alternatively ionized Ca2+ could be measured):
Ca = SerumCa + 0.02 * (NormalAlbumin - PatientAlbumin) (SI UNITS)
Pseudohypercalcemia can occur when patients are hyperalbuminemic or have a multiple myeloma with a paraprotein that binds calcium (rare) - in these cases total CA2+ will be high, but ionized CA2+ will be normal.
TREATMENT
FLUIDS!!!!!!!!
Infusion rate depends on volume status, heart function, etc, but should target 100-1500 cc urine output/hr - do not need to hydrate beyond euvolemia
If severe/symptomatic consider: Bisphosphonates (IV) - will not take effect for 48-72 hrs, but will help maintain normal calcium when achieved.
Calcitonin by nasal spray or subQ is also very effective.
If hyperCa2+ is from sarcoid or lymphoma consider steroids (20-40 mg/day) - this works by decreasing calcitriol production from activated mononuclear cells in the lung and lymph nodes.
AVOID LASIX since most patients are profoundly volume depleted initially and once replete can cause hypokalemia, hypomagnesemia, and lead to recurrence of volume depletion. A recent Annals of Internal Medicine article reviews the use/concerns regarding Lasix in hypercalcemia.
Dialysis should be consider if the above fail/can't be done because of renal failure or heart failure.
Wegener's Granulomatosis
When patients with chronic disease (such as Wegener's) present with an acute problem, one should consider if this is a process related or unrelated to their underlying disease. Attempts to evaluate the "activity" of the chronic disease should also be made.
When patients are admitted to hospital, careful thought should be given to what tests are ordered at time of admission. Although we should all try to attempt to minimize unnecessary investigations, if a patient is going to be in hospital for more than a few days it may be helpful to get "baseline" CXR, ECG and "routine bloodwork". This will may serve as a useful comparison should they develop further complications associated with their admission diagnosis or adverse events from hospitalization or treatment.
A 1997 NEJM review of small vessel vasculitis is available here.
A review of the evidence of PCP prophylaxis in non HIV infected patients is available here.
Friday, July 31, 2009
Quality of Care
It found that in GIM M+M conferences case presentations were longer than those in surgery M+M. Less time was spent on audience discussion, fewer case presentations included adverse events or errors causing adverse events. At surgery M+M, errors were more likely (P=.17) to be attributed solely to an individual rather than a team or system.
Tuesday, July 28, 2009
"That's Tight" - How to assess for Aortic Stenosis
We also briefly discussed multiple myeloma. A review in BLOOD was published in 2008. Treatment in this field has evolved rapidly over recent years.
Finally, we discussed the physical exam diagnosis of aortic stenosis. The findings of a paper examining a clinical prediction rule for AS is summarized in the following figure from the article.
Abscence of a murmur over the right clavicle (see article Table 1 for how to auscultate for this) as performend by a staff internist or senior medical resident, effectively rules out moderate to severe AS (usually more important clinically than ruling in AS, as to rule it in a TTE will often be performed).
The JAMA rational clinical exam "Does this patient have an abnormal systolic murmur?" can be found here.
Monday, July 27, 2009
The Pneumonia formerly known as PCP
Pneumocysitis jirovecii pneumonia was previosuly named Pneumocystis carinii pneumonia. Some of the debate regarding the name change can be found here and in the associated references. Previously classified as a protozoa, but molecular studies have shown it to likely be a FUNGUS.
Generally occurs in HIV+ patients with a CD4 count below 200 cells/mm3. Can also occur in other immunosuppressed hosts.
PRESENTATION
Subacute onset of (exertional) dyspnea, dry cough +/- "low-grade" fever.
Physical Exam shows tachypnea, tachycardia and normal lung auscultation in 50% (the remainder having crackles etc.).
CXR - classically bilateral, perihilar interstitial infiltrates, but can show almost anything (or nothing). However, pleural effusions and/or lymphadenopathy is very rare.
DIAGNOSIS
In addition to the clinical presentation, microscopic examination of (induced) sputum, BAL fluid or tissue can be performed. PJP cannot be readily cultured (be sure to specify you want sputum tested for PJP if it is in your Ddx), it can be seen with methenamine silver or immunofluorescence stains.
Laboratory data is generally not very informative. LDH is elevated in 90%, but this is very non-specific.
TREATMENT
TMP-SMX - high dose (see reference) x 21 days. Alternatives included inhaled pentamidine and atovaquone. Remember to start prophylaxis after finishing treatment!
Patients with PCP may worsen after two to three days of therapy, possibly from inflammation in response to dying organisms.
Corticosteroids are of benefit in patients who are hypoxic at presentation (PaO2 on room air less than 70mmhg or oxygen saturation <90%)
The benefit of steroids in PCP was shown in a study conducted in Toronto in 1987.
A NEJM review article can be found here
Thanks to prior CMRs for some of the above.
As discussed at noon rounds: Nystatin was isolated from Streptomyces noursei by Elizabeth Lee Hazen and Rachel Fuller Brown. The soil sample where they discovered nystatin was from the garden of Hazen's friends, Walter B. Nourses, therefore the strain was called noursei. It contained a substance that they first named fungicidin, a name that had already been used for another substance. They then renamed the substance nystatin in honor of the New York State Public Health Department, where they worked.
Tuesday, July 21, 2009
What's the diff?
Gram positive anaerobic bacillus - cytotoxin producing. Disease caused when toxin(s) bind to the surface of intestinal epithelial cells, where they are internalized and catalyze the glucosylation of cytoplasmic rho proteins, leading to cell death.
Typical occurs in elderly/instiutionalized especially after receiving antibioitics. Historically Clindamycin has been associated with high risk of C diff, in the Quebec outbreak in 2003, fluoroquinolone use was also associated with the development of infection. Direct person-to person spread occurs and previously healthy/younger/non institutionalized patients have also been infected.
PREVENTION
need responsible antibiotic use
infection-control measures (contact precautions, hand hygiene, environmental decontamination)
DIAGNOSIS
Microbiology
- C. diff toxin assay (EIA) detects toxins A and B and has ~70% sensitivity, with ~90-95% sensitivity on three tests. The specificity is> 95%.
- The most sensitive assay is the test for cytopathic effect, which is not available here
- You can also culture Clostridium difficile from the stool, but this is not routinely done, as there are nonpathogenic strains
- A positive toxin assay in a patient with minimal or no symptomsshould not prompt treatment. (i.e. only send for toxin testing if there is sufficient pre-test probability)
- Consider AXR to assess for toxic megacolon -a maximum colonic diameter greater than 6 cm is consistent with megacolon, may also see bowel wall changes
- CT scan helpful for further assessment and to R/O other causes of colonic distension etc.. May show thickening of the bowel wall, colitis, ileus
Sigmoid/Colonoscopy
Generally avoided with typical presentation and positive toxin EIA
Concern regarding endoscopy/insuflation of air causing perforation, especially if toxic megacolon present
May see pseudomembranes diagnostic of pseudomembranous colitis
Consider endoscopy if:
- Atypical presentation (ileus etc.)
- Other diagnoses suspected/need to be ruled out
- Failure of C. difficile infection to respond to therapy
See table from NEJM review here.
First Episode
***If possible stop offending antibiotics***
- Mild/Moderate Disease
- Metronidazole OR Vancomycin (PO) duration 10-14d
- Metronidazole OR Vancomycin (PO) duration 10-14d
- Severe Disease
- Defined as:
- Two of (Age above 60, Febrile, WBC above 15, Albumin below 25)
- OR hypotension/shock or Cr greater than 1.5x normal, or toxic megacolon, peritoneal signs, perforated bowel
- Two of (Age above 60, Febrile, WBC above 15, Albumin below 25)
- Infectious Disease +/- General Surgery Consultation
- ICU Consult for patients with hemodynamic comprimise
- Vancomycin (PO) unless severe illeus/toxic megacolon, then Metronidazole (IV) duration 10-14d (Vanco has more rapid symptom resolution and a lower risk of treatment failure).
- Defined as:
- First relapse --> can repeat last treatment depending on severity
- Second relapse --> vancomycin taper. ID consult.
NEJM Review article (2008) can be found here.
A paper discussing Vanco as first line treatment can be found here.
Thanks to Dr. T.C Lee for some of the above post.
Thursday, July 16, 2009
Gallstone Ileus
Occurs after gallstone lodges in bowel (generally terminal ileum - the narrowest intestinal area). The stone gets into the gut through a biliary enteric fistula.
Average age of affected patients is 70 years, more common in women.
In a large surgical series of patients undergoing cholecystectomy described here:
1.8% had a cholecystoenteric fistula
90% of patients with a cholecystoenteric fistula had Mirrizi syndrome (common hepatic duct obstruction caused by extrinsic compression from an impacted stone in the cystic duct)
5.7% of patients had Mirrizi syndrome
PRESENTATION
Classically a subacute obstruction in an elderly female that occurs episodically as the stone passes through and transiently obstructs the GI tract. (Transient) abdo pain, vomitting, abdo distension, increased bowel sounds
Bouveret's syndrome - gastric outlet obstruction secondary to an impacted gallstone in the duodenum or pylorus
Less than 15% of gallstones can be seen on plain film. Other AXR findings - parital or total SBO, pneumobilia. CT scan is likely better to visualize the stone/obstruction and MRCP may be best to define biliary anatomy
TREATMENT
Supportive until definitive treatment.
Surgical - enterolithotmy (with care to examine for >1 stone) +/- concurrent cholecystectomy or delayed laparoscopic cholecystectomy
Alternatives - extracorporeal lithotripsy, endoscopy (not first line)
Tuesday, July 14, 2009
"When you're sliding into first...."
A good discussion on the differential diagnosis of bloody and none bloody diarrhea of acute onset occurred today.
As always, a good history (as always) goes a long way in helping to focus the picture. In addition to a travel/sick contacts/dietary/medication history, sexual history is also important.
It is recommended that all patients with acute bloody diarrhea (including on history and FOB +) undergo stool culture.
DIFFERENTIAL DIAGNOSIS
Infection:
cytoxic - E. coli (EHEC) O157:H7 (often present with no fever), C. Difficile
invasive - E. coli (EIEC), Salmonella, Shigella, Yersinia, Campylobacter
Inflammatory: Inflammatory Bowel disease, radiation proctitis/colitis
Ischemic Colitis
Non diarrheal causes of Lower GI bleed should also be considered (diverticular disease, etc.)
Other considerations are rarer and depend on immunosuppression (CMV colitis) and exposure (GI anthrax, Intestinal TB, intestinal amebiasis, HSV procitis etc.)
A study of infectious etiologies (determined by stool culture) of acute bloody diarrhea in patients presenting to the ER in the US is posted here. If found enteropathogens in 12.5% of cases that were cultured despite the physician's presumptive diagnosis of a noninfectious cause.
A second study of the clinical and epi factors of diarrhea in the U.S. is posted here.
For an excellent blog on Infectious Disease issues see: http://www.idologist.com/Blog/
Friday, July 10, 2009
NASH
CAUSES:
Metabolic Syndrome - obesity, diabetes, hyperlipidemia
Metabolic - hypothyroidism, TPN, rapid weight loss
GI surgery - gastroplasty, jejunal bypass, small bowel resection
Drugs - Tamoxifen, amiodarone, prednisone, estrogens
TREATMENT: Modify risk factors. Weight loss should be gradual as rapid weight loss can worsen the liver injury. Identify and treat underlying causes (hypothyroid, meds, etc.). Preliminary studies have shown that metformin or pioglitazone may one day have a role in treatment, but their exact longterm benefit is not clear.
Click here for a 2002 NEJM Review article.
Cholesterol Emboli
ACUTE RENAL FAILURE:
A standard approach
Prerenal: Volume depletion, hemorrhage, decreased effective circulating volume (CHF, cirrhosis), renal artery stenosis
Renal: Glomerular - Glomerulonephritis (and its associated long list of causes), Acute interstitial nephritis, Acute tubular necrosis (either ischemic or nephrotoxic), Vascular
Postrenal: Obstruction of collecting system or extrarenal drainage
PERIPHERAL EOSINOPHILA
While discussing laboratory findings of AIN, the differential diagnosis of a peripheral eosinophilia was reviewed:
Allergic - rhinitis, asthma, meds.
Infectious - parasitic (helminths), fungal, other
Hematologic - Hypereosinophilia Syndrome, leukemia, lymphoma
Specific Organ Involvement - blood eosinophilia can occur when tissue eosinophilic infiltration is present in pulmonary, GI, derm, cardiac, rheumatologic or renal disease
CHOLESTEROL EMBOLI SYNDROME
Occurs in people with atherosclerotic disease
Spontaneous or as a result of intravascular procedure
Result of cholesterol crystal embolism causing occlusion of multiple small arteries leading to further inflammation and intimal proliferation
Pathology - "ghosts" of cholesterol crystals as they are dissolved during fixation
Symptoms:
Non specific H/A, myalgia, fever
Derm -livedo reticularis (lacy rash), ulceration, gangrene, "blue toe syndrome"
Acute Renal Failure -
GI - intestinal ischemia
Eyes - Hollenhorst plaques (cholesterol crystals in retinal arteries)
Labwork - nonspecific: elevated WBC/ESR, hypocomplementemia, Cr and urine eosinophils (if renal involvement), eosinophila
In the abscence of other symptoms consistent with cholesterol emboli, post angiogram renal failure will often be diagnosed as contrast nephropathy. Ways to try to distinguish the two:
- Presence of other signs of cholesterol emboli (obviously)
- Transient eosinophilia/hypocomplementemia
- Persistent renal failure (much less common in contrast nephropathy)
See a picture of Hollenhorst plaque (from UMich) below:
Wednesday, July 8, 2009
"Poncho Sign" and Heliotrope Rash
Dermatomyositis and polymyositis = inflammatory myopathies that are often discussed together because they often present as symmetric proximal muscle weakness.
Dermatomyositis, however, is associated with skin findings and is much more likely to be associated with an underlying malignancy.
SKIN FINDINGS - Heliotrope rash (see picture),Gottron's papules, periungual changes, "mechanic's hands", and the shawl sign - which some MDs felt appeared more like a poncho sign in certain patients.
Lung Involvement - ILD, respiratory muscle weakness
GI Involvement - Dysphagia, regurgitation, aspiration
Cardiac Involvement - Myocarditis, pericarditis, arrhythmias
SEROLOGY - ANA+ in 80%. Ongoing research into myositis specific antibodies (currently felt to be present in 30%) to help determine likely clinical progression and treatment response
MALIGNANCY - Incidence of cancer is 5-7x higher than general pop'n. Peak incidence of diagnosis is within 2 years before or after the DM diagnosis. Search guided by complete history and physical. Bloodwork, imaging and tumor markers (CA125, CA 19-9, PSA) and age appropriate cancer screening.
Ongoing cancer surveillance suggested for 3-4 years after diagnosis or recurrence, with the exception of ovarian CA which can occur >5 years after diagnosis (therefore screen for longer).
Publications on malignancy frequency in DM/PM can be found here (don't forget they have a higher baseline incidence of nasopharyngeal CA in China - it isn't the most common DM associated cancer here) and here.
THERAPY- Treat the cancer!! (If you can find it without going overboard looking!)
Involves steroids at relatively high doese for prolonged periods of time. Steroid sparing agents such as azathipone and methotrexate are also used. Guided by clinical exam/weakness rather than CK/other markers.
As steroid course will be prolonged, be sure to consider the associated side effects and posible infections including TB.
Patients with polymyositis/dermatomyositis who have interstitial pulmonary fibrosis may be at increased risk for PCP with glucocorticoids alone compared to other populations.
A review of treatment can be found here.
Monday, July 6, 2009
Atrial Fibrillation
First question - STABLE vs UNSTABLE?
(Instability rare if HR<150)>
Unstable if - hypotension, chest pain, altered mental status, other signs of shock
If Unstable - requires immediate synchronized cardioversion (with appropriate sedation, monitoring, etc).
If stable - consider rate control (oral or IV) with agents such as beta blockers, calcium channel blockers (Non-dihydropyridines) and amiodarone - depending on the clinical situation/contraindications.
The ACLS Tachycardia algorithim can be found here.
ANTICOUAGULATION in chronic/paroxysmal AFIB:
Initiated to prevent embolic stroke.
Risk similar in chronic vs paroxysmal AFib
CHADS2 score - used to risk stratify patients
C-Congestive Heart Failure (1point)
H-Hypertension (1point)
A-Age>75 (1point)
D-DM (1 point)
Stroke/TIA - (2 points)
CHADS2 score of 0 associated with 0.5%/year chance of stroke without coumadin
CHADS2 score >=3 associated with >5.3%/year chance of stroke without coumadin]
Patients with higher stroke risk will have greater benefit with anticoagualtion.
See the original article here.
Informed discussions should take place with patients to determine the risk/benefit of starting on anticoagulation with coumadin (target INR 2-3).
MDs are often concerned about starting anticoagulation in patients who fall. A decision analysis conducted in part by a Toronto based researcher suggested that patients with an average risk of stroke from AFib would have to fall 300 times in one year for the risk of anitcoagulation to outweigh its benefit - see article here.