Nephrolithiasis - When Should I Admit?

I recently had a patient who came in complaining of severe flank pain radiating to his groin with nausea and vomiting… it was determined that he had nephrolithiasis (kidney stones). My attending asked me whether or not we should admit the patient… Good question, I thought. I was able to rattle off the text book treatments, but I wasn’t clear on the guidelines for admission vs. out-patient treatment. Below is an overview of treatment including some clear indications for admission.

General Treatment (for all types of stones):

1-PAIN CONTROL!

a-PO analgesic or IV morphine, situation dependent

b-Parenteral NSAID (Ketorolac)

2-Hydration (vigorous)

3-Antibx, if UTI present

Additional treatment measures based on pain severity:

MILD-MOD pain = high fluid intake, oral analgesics, wait for stones to pass (Give pt a urine strainer because you want to know what “kind” of stone the patient has.)

SEVERE pain = IV fluids and pain control, KUB, IVP to find site of obstruction, consult urology (surgery) if stones do not pass in 3 days

ONGOING pain w/o relief from narcotics = Surgery

Types of Surgery (10,000 foot view):

Shock wave lithotripsy: most common, it breaks apart the larger stones so they can be passed spontaneously, typically used for stone >5mm and < 2cm

Percutaneous nephrolithotomy: used if the above fails, if stones are > 2cm, for struvite stones

Admission is indicated if:

1-Oral analgesics are insufficient to manage the pain.

2-Ureteral obstruction from a stone occurs in a solitary or transplanted kidney.

3-Ureteral obstruction from a stone occurs in the presence of a urinary tract infection (UTI), fever, sepsis, or pyonephrosis.

4-Large stones (>1cm)

*The above indications were found in a couple of sources, but more say that the ultimate decision is made on a clinical basis, not solely on guidelines.

Parting suggestion: brush up on the different kinds of kidney stones

Sources:

Medscape: Nephrolithiasis and Treatment, http://emedicine.medscape.com/article/437096-treatment

Step Up to Medicine 2^nd Ed. by Agabegi and Agabegi

Picture: http://knol.google.com/k/kidney-stones#

Treating Hyponatremia in the ED

After reading this blog entry from EM CRIT BLOG I felt better regarding the treatment of hyponatremia so I thought I would share. This blog has some great information and most blogs have a podcast option.

"In this podcast, I discuss the management of hyponatremia in the ED. After reading countless articles from the nephrology literature…I can still attest that I have not a friggin’ clue about renal physiology. But I think I have found a simpler path to the work-up and treatment of low sodium in the ED."

Click here for rest of entry...

Levothyroxine vs Brand-Name

I vaguely remembered a comment from our endocrine teacher about not putting our patients on generic levothyroxine for hypothyroidism and that we should always opt for a brand name if the patient could afford it -- but the exact reason why had escaped me. I was recently presented with a situation in which I needed to make the call - generic vs brand - so I did some research and spoke to an endocrinologist. These are the main points that I came up with...

1. For tight control of TSH, use a brand name (which brand isn't important)
2. Tight control is particularly important in pregnant women, those looking to get pregnant, and those with h/o goiter or thyroid cancer
3. Once you pick a brand, try to stick to the same brand-name each month
4. The problem with generic levothyroxine is that the manufacturers producing the drug are variable and there are many companies moving in and out of the market so it is difficult to get the SAME generic pill each month from the pharmacy
5. If your pt can only afford generic, encourage them to take a photo of the pills that they get from the pharmacy - if they ever pick up their Rx and the pills look different then they should contact you to schedule thyroid blood work check in 5-6 weeks since the new generic could vary as much as 12.5%. If they are receiving the same generic pill each month, you should schedule normal follow ups. The bottom line is that each time they get a new generic pill from a new manufacturer, they should be re-tested.

This becomes important because many primary care providers Rx the generic because they believe that it isn't any different from brand names - and in most cases they are completely right. Ibuprofen vs Advil - no real noticeable clinical difference. The thyroid, however, is extremely sensitive and even the slightest variation from generic #1 to generic #2 can make someone's TSH impossible to tightly control and may even make them thyroid toxic.

When I presented this to several PCPs, it was received with a lot of skepticism. The first question they all asked was "Who did the study, the drug companies?" A great question to ask. The answer is... in addition to drug company studies... there have been independent studies and results have been examined by the FDA, Endocrinologist Societies (world-wide), and the Thyroid Association - all are in agreement about the results. There is a ppt available describing the results of these studies. They show the bioequivalence of generic vs brand, but also demonstrate the vast variability between generic manufacturers.

If you are looking for a quick 1 page break down of this subject - check out the following: Hennessey JV. Levothyroxine dosage and the limitations of current bioequivalence standards

Thyroid Resource

Quick post to share a great website resource I just found on the thyroid. It has up to date information and reviews of studies as well as ppts to explain relevant treatments for thyroid disease.

Thyroid Today

Click on pic to enlarge

OB/GYN Study Sources

I have had a few people ask me which books I used to prepare for my OB/GYN rotation so I thought it would be a good idea to share with everyone. The 4 main sources that I used to study before/during my rotation are:

1. Blueprints: OB/GYN ($35-40)
2. Case Files: OB/GYN ($25-30)
3. Obstetrics, Gynecology, and Infertility (Great pocket guide) ($15)
4. UpToDate.com (which I can only use at the hospital because I do not have a personal subscription)

I wanted to share a little about the Case File series because although I had heard of them before, I hadn't used them -- but now that I have - I love the set up. Each chapter starts with a brief case vignette and a couple questions such as: What is the likely diagnosis? or What would you do next? Then you are given the answers along with a brief teaching section on the topic. Lastly, they give you 5 or so multiple choice questions covering the chapter material (answers included). By the end of each chapter I really felt like I knew the material. This set up may not be for everyone so I took some page-shots so you can check it out before you make the purchase. I borrowed mine from the school library for the duration of my rotation.