Tuesday, June 26, 2007

summer safety tip #1

it's sweltering today.

i mean, hot and humid. the reason i can never live in the south.

i tried to run early this morning to avoid the humidity, but it was already almost unbearable. the only place with a breeze was by the river. seems like people might be tempted to go swimming today. in fact, i'm sure that a lot of folks will. i only hope they adhere to this very important summer safety tip:


i am on PICU night float this month. already, we have had two cases of hemolytic uremic syndrome, or HUS, one of which was likely caused by a child swimming in a water source contaminated by Escherichia coli 0157:H7.
HUS is a syndrome that is typically characterized by a prodrome of diarrhea (90%) or an upper respiratory tract infection (the other 10%). the classic triad of HUS is hemolytic anemia, thrombocytopenia and acute renal failure. it usually occurs in kids <4 style="font-style: italic;">Yersinia, Salmonella, and Campylobacter species, Streptococcus pneumoniae and Clostridium difficile. 70% of HUS cases in children result from E. coli 0157:H7 or Shigella dysenteriae, both of which produce a toxin (shiga- or vero-toxin) that damages the lining of the blood vessels, or endothelium, throughout the body.

the effect of this toxin-mediated damage is profound. fibrin and platelets adhere to the damage on the vessel walls, resulting in low platelets (thrombocytopenia) and tiny little clots called microthrombi. red blood cells are either damaged by the toxin or chewed up as they try to flow past these thrombi (a process called microangiopathic hemolytic anemia).
(normal red blood cells above, damaged red cells below, called schistocytes.)

in HUS, these microthrombi occur primarily in the kidney, resulting in kidney failure. but, really, any organ can be involved. the picture below is of a portion of a kidney called the glomerulus, which is really just a tuft of small blood vessels. the light pink smudgy stuff at the end of the arrow is a microthrombus.

in a similar disease process seen more commonly in adults, thrombocytopenic thrombotic purpura (TTP), microthrombi occur in the brain, spleen, liver, pancreas, heart and kidney. TTP has a much poorer prognosis.

both kids in question had had several days of bloody diarrhea. we're not talking a few streaks here and there that you could explain with a fissure or hemorrhoid. we're talking lots of blood. both were dehydrated, anemic and thrombocytopenic. both had stool cultures that were positive for E. coli 0157:H7. both were in renal failure and are now at TBFCHITW (that's for you, flea, if you are reading this) on dialysis.

one of the most important questions from a public health standpoint is how did they get it? E. coli live among us. most are not harmful and are considered normal flora in our intestines. you might hear them referred to as coliform bacteria. we actually need these commensal organisms to digest our food. They actually make vitamin B12, amongst others, that we need to live. the 0157:H7 serotype is not so friendly or helpful.

0157:H7 is in contaminated meat, such as hamburger. if this doesn't make you want to be a vegetarian, nothing will. you are actually more likely to get 0157:H7 from hamburger than from a steak, as the bacteria are on the surface of the steak (and, hence, are killed in the cooking process) but get mixed up when the beef is ground up to make hamburger. raw or undercooked hamburger is often the culprit with outbreaks of 0157:H7.

another potential source is inadequately washed or unwashed produce. remember the spinach that was the source of the outbreak last fall? it's called fecal-oral contamination. enough said.

0157:H7 also lives in and on cows and other farm animals. some outbreaks have been tied to petting zoos.

contaminated water supplies are another concern, particularly in rural areas where there are a lot of cattle. pay attention to the coliform counts! this tells you how much poop has been in the water. the fish and wildlife service checks water supplies for coliform counts regularly and will close a pond or lake if the level is high enough.

the moral of this cautionary tale is to:
1) avoid contaminated water supplies (aka, the feculent pool)
2) take your child to the doctor when they have bloody diarrhea (please do this if nothing else!)
3) avoid raw/undercooked beef, unwashed vegetables/fruits, and unpasteurized milk or fruit juices

when it comes to E. coli 0157:H7, an ounce of prevention is worth everything.

Saturday, June 23, 2007

ondine's curse

he lay quietly, the rhythmic breaths from the vent lulling him deeper into sleep. his mother, weary from lack of sleep, sat in a chair at the bedside, unwilling to leave him. if he woke, he would want her.
before this night, i did not know the extent of their journey together, this young boy and his mother. as it became clear that he would sleep soundly, the tension drained from her face. i asked her how it all began. as she eagerly began to recount their story, i was struck by how young she looked, after having been through so much.
there were multiple, frustrating trips to emergency rooms, doctors who told her that there was nothing wrong. once it became clear to all who knew him that there was, indeed, something wrong, an excruciatingly long stay in the PICU. yet, still, no diagnosis.
finally, after much searching and many tests, the diagnosis was clear. ondine's curse. congenital central hypoventilation sydrome (CCHS), a rare disorder that causes sleep apnea and usually requires tracheostomy and life-long mechanical ventilation, but only at night.

the name of the disorder, ondine's curse, comes from the myth of ondine. in the current rendition of the story, ondine was a water nymph, stunningly beautiful, who fell in love with a human. when she married him and bore his child, she lost her immortality. as she aged, her husband lost interest in her and was unfaithful to her. she discovered him in the arms of another woman and cursed him, telling him that as long as he remained awake, he would live, but as soon as he slept, his breath would desert him.

in the original tale, "Undine" by Friedrich de la Motte, undine's father, a prince of the mediterranean sea, wishes for her to possess a soul, as undines' do not have souls. (undines are spirits of the elements, earth, water, wind, fire.) he sends her to live with a fisherman and his wife who have lost their own daughter, bertalda, after she wandered away (lured by undine's uncle, kuhleborn).

when undine is 18, a knight, huldbrand von ringstetten, comes to the fisherman's cottage and falls in love with her. only once they are married does she tell him of her heritage. she tells him that if he is to reject her, to do it then and she will return to the crystal palaces of her father, "a soul-endowed woman". huldbrand does not reject her, but vows his never-ending love for her and takes her to live with him in his castle near the danube.

bertalda, who finally discovers her true identity, lives with undine and huldbrand. undine's water-spirit uncle, kuhleborn, will not let them live in peace. he haunts them by emerging from the fountain of the castle and taking human form. to prevent him from doing so, undine places an enchanted stone over the fountain to keep kuhleborn away. they live peacefully for a time.

however, when the three of them attempt to travel to vienna, bertalda drops her necklace, given to her by huldbrand, into the water. undine summons a beautiful red coral necklace out of the watery depths. huldbrand is enraged by this, realizing that his beloved wife is still connected to her water-spirit family. despite undine's warning that should he ever be angry with her that her family will recall her to her watery home, huldbrand expresses his anger and undine is taken back beneath the water where she lives in sorrow. as long as huldbrand is faithful to her, he can continue to draw breath. if he is not, he will die.

at first, huldbrand is grief-stricken and weeps and weeps for his beautiful undine. however, his grief for his wife fades and he eventually plans to wed bertalda, even though his love for undine remains true. bertalda agrees to marry him even though she knows he is still in love with undine. the night before their wedding, bertalda foolishly removes the stone from the fountain, allowing undine to rise from the water to fulfill her curse:
There was a gentle tap at his door. Undine used to tap thus when she wanted playfully to tease him "It is all fancy," said he to himself; "I must seek my
nuptial bed."

"So you must, but it must be a cold one!" he heard a tearful voice say from without, and then he saw in the mirror his door opening slowly--slowly--and the white figure entered, carefully closing it behind her. "They have opened the spring," said she softly, "and now I am here, and you must die."

He felt in his paralyzed heart that it could not be otherwise, but covering his eyes with his hands he said: "Do not make me mad with terror in my hour of death. If you wear a hideous face behind that veil, do not raise it, but take my life, and let me see you not."

"Alas!" replied the figure, "will you then not look upon me once more? I am as fair as when you wooed me on the promontory."

"Oh, if it were so!" sighed Huldbrand, "and if I might die in your fond embrace!"

"Most gladly, my loved one," said she; and throwing her veil back, her lovely face smiled forth divinely beautiful. Trembling with love and with the approach of death, she kissed him with a holy kiss; but not relaxing her hold she pressed him fervently to her, and as if she would weep away her soul. Tears rushed into the knight's eyes, and seemed to surge through his heaving breast, till at length his breathing ceased, and he fell softly back from the beautiful arms of Undine, upon the pillows of his couch--a corpse.
the story has been immortalized in many different forms, ballet, theater, animation (disney's "the little mermaid" is a veiled re-telling of the myth), painting and sculpture (the above painting, "Ondine", is by Paul Gaughin). time has changed the essence of the story, which, it turns out, is quite beautiful and tragic.

the boy slept soundly all night. after telling me their story, his mother slept soundly, as well. the reason they are in the PICU? he had phrenic nerve pacemakers placed. once they are turned on next month, controlled by a remote control box, the pacemakers will stimulate his phrenic nerves, which stimulate his diaphragm to move and, thus, to breathe. eventually, we will be able to remove his trach and he will be able to talk and laugh and breathe, even as he sleeps. amazing.

Sunday, June 17, 2007

terrapin station

i was driving home tonight after a surprise farewell dinner party organized by a 5yo CF patient for her beloved pulmonologist (and my incredibly wonderful mentor). it was a fun evening, full of stories, laughter, and the entertaining antics of the 5yo and her little brother, almost 2yo.
as i walked to my car, feeling a little bittersweet, i looked up and saw a thin sliver of a crescent moon and venus, nestled in the moon's curve. it reminded me of an old, favorite grateful dead song.

"Counting stars by candlelight, all are dim but one is bright;
The spiral light of Venus, rising first and shining best,
All along the northwest corner, of a brand new crescent moon,
While crickets and cicadas sing, a rare and different tune,
Terrapin station."

i can't quite explain why, but it was one of those moments when you just have to pause and wonder at the beauty of everything.

Saturday, June 16, 2007

a rhetorical question

why is it that men are never more interested than when a woman seems disinterested or, at the most, ambivalent?
i got called down the the ED last night for some emergent ear pain at 3:30am. turned out to be a ruptured ear drum, quite painful but also not quite an emergency. while i was down seeing this child, i ran into another resident with whom i used to hang out. we may have had a few dates last fall. he seemed interested at first, but then not so much, so we just drifted. i hadn't seen him in quite some time until last night. suffice to say, he seemed interested again. what is it about guys? why can't they make up their minds?

Sunday, June 10, 2007

a running interlude

i went for my long run today. yup. i'm training again for the half-marathon in august to raise money for our hospital.
i went on a new route today, courtesy of one of the picu nurses who lives in my neighborhood and runs it all the time. it's was great. it takes you out on back roads in vermont that ever so gently roll. there are a few hard hills, but they fortuitously hit just as the nirvana section of my running mix kicked in. plus, the view at the top is stunning. there's not too much traffic, only when it loops back around to cross over the bridge into new hampshire. but that section is pretty short and there's a sidewalk.
i was post-post-call today, which is actually the worst day in terms of fatigue after being up all night. but i pushed through the haze and protest from my quads and persevered.
this year, my goal is to raise more money ($1006 last year) and finish faster. last year was all about proving to myself that i could actually do it. this year is about doing it with style and much, much more grace. given that i actually have time to train, it just might happen.

Saturday, June 09, 2007


so i've got a lot of cross-cover in the picu this month.

cross-cover is when you are on-call at night for a service that you are not rotating on that month. in the picu, this can be a bit dicey, as the kids can be quite sick (obviously) and you don't really know them. we have a 10-bed picu. compared to some hospitals, that's pretty small. so, you think, how bad could it really be, right? well, it can be bad. especially as our attendings are not in-house and you are basically on your own. Thank god for picu nurses.

i blogged about my first cross-cover this month in a recent post.

last night wasn't as bad, but it still freaked me out and i didn't leave the unit.

i managed 9 kids, 4 of whom are on vents, 1 of whom was the first kid i'd ever managed with DKA, or diabetic ketoacidosis.

DKA is how many children present when they are first diagnosed with type I diabetes, which is the type associated with autoimmune destruction of the pancreas and, thus, endogenous insulin production.
Normally, when you eat food, your body breaks it down into smaller parts, including glucose from carbohydrates. When glucose levels in your blood rise, this triggers your pancreatic cells (see diagram below) that make insulin (the islets of Langerhans) to secrete insulin. your liver, fat and muscle cells need insulin in order to use glucose for energy.

In type I diabetes, the islets of Langerhans have been destroyed by autoantibodies. So you can't release insulin in response to elevated blood glucose levels.
when glucose builds up in your bloodstream, that's bad. in order to keep your brain going, your body starts to use fat to make energy, resulting in the formation of ketone bodies (the keto- in ketoacidosis). these use up your buffers, resulting in acidosis. the elevated blood glucose results in an osmotic diuresis. a typical patient with DKA is about 7-10% dehydrated as a result. dehydrated and essentially starving. this kid had lost 15lbs in 3 weeks.

in a purely abstract way, it's sort of fun to manage these patients. i'm an orderly person. i like things that are predictable, things that make sense. when you are reversing the acidosis of a kid with DKA, it's orderly, predictable. the glucose falls, the pH corrects, the sodium rises, the potassium falls. usually the phosphate falls, too. you can anticipate all these things, plan for them. hourly labs. data sheets to track your progress.

in a not so abstract way, it's not so fun to manage these kids. they're scared. sometimes they are super sick. they are getting poked hourly for blood. their life is changing and they feel completely out of control. from a doctor's perspective, you are scared to death that they will get one of the dreaded complications of DKA, cerebral edema, so you're constantly checking their mental status to make sure they are not deteriorating. i kept asking this kid's nurse to wake her up and see if she had to pee. she didn't. and i think i just ended up annoying my nurse. good thing he likes me and just thinks i'm funny when i get all paranoid.

this kid did really well. no cerebral edema. by 4am, her glucose was normal again, her serum ketones were almost cleared. she didn't have horrible sodium or potassium derangements. her acidosis had corrected.

all was well in terms of her physiologic state.

she has a long road ahead of her, but she strikes me as one of those mature-for-her-age kids who will do just fine.

Wednesday, June 06, 2007

knocked up

for those who need a good laugh, go see the new jeff apatow movie, knocked up. it's fairly clear that the script was written by a man, but it's worth seeing anyway. i laughed. and i desperately needed a good laugh.

Tuesday, June 05, 2007

the myth of sisyphus

post call today after a long, sleepless night in the PICU. i have this vague recollection of leaving the bedside at one point to brush my teeth, but otherwise, not at all.

i am left with a sense of defeat, as if i have been foolishly trying to hold water in a sieve. no matter how much water i put in, it all just flows out again, mocking my efforts and highlighting my naive, all-too-tentative confidence that i know what i am doing.

as the sun began to appear on the horizon, the nurses and i took a moment to breathe and enjoy the beauty. she was momentarily improving, but my intuition was that this, too, would pass.

these are the patients that leave you wondering why it is that we do what we do, when it just seems futile? as if god, if you believe in such an entity, just has a different plan? you struggle to eek out some small iota of change. but in the end, the DIC, ARDS, and sepsis win, just as sisyphus' rock inevitably rolls back down the hill. yet, he rolls it back up again.

i have blogged in the past about other chronically ill children who have passed away, some with more peaceful deaths than others. as a general rule, i support a family's desire to do everything possible. so what do you do in cases where respecting the family's wishes feels unethical? when it feels like every intervention is painful and only serves to prolong the patient's suffering?

when i came home this morning, the sun was shining. spring is in full force here and it is breathtaking. i fell asleep and did not dream. i awoke this afternoon to lightning, thunder and the sound of sheets of rain falling on my metal roof. as i sit here typing, the rain has passed, the storm clouds are receding to the east, the sun is peeking through the clouds again over the greens. mother nature as metaphor.

Sunday, June 03, 2007

what are the chances?

i drove home from smallish state to even smaller state last night through the most amazing lightning storm. it got me thinking. what is it about a car that makes it a safe place to be? what are the chances that you'll get struck by lightning? are you more likely to get struck by lightning or to get swept away by an avalanche? well, i suppose the latter would depend on whether you lived in a place where avalanches occur.
at any rate, i googled lightning strikes this morning and found all the answers to my questions and then some.
-you have a 1:5000 chance of getting struck by lightning during your lifetime
-9 out of 10 people survive a lightning strike
-a lightning bolt strikes the earth a hundred times a second, heating the air around it 5 times hotter than the surface of the sun
-lightning strikes kill more people each year than tornadoes or hurricanes (about 2000 people worldwide each year versus 150 people killed by avalanches each year)
-cars are safe not because they aren't struck but because the tires conduct the charge to the ground
-lightning bolts start as negatively charged particles that extend towards the earth and are met by positively charged particles called streamers extending up from the earth; when the two oppositely charged particles meet, an electric current is formed that makes the flash (for a really neat demo, check out this national geographic interactive site (yes, i am aware that i am a geek).

some safety tips from national geographic (what can i say, i'm a pediatrician ;):
  • If outside, seek refuge in a car or grounded building when lightning or thunder begins.
  • If inside, avoid taking baths, or showers, and washing dishes. Also avoid using landline phones, televisions, and other appliances that conduct electricity.
  • Stay inside for 30 minutes after you last see lightning or hear thunder. People have been struck by lightning from storms centered as far as 10 miles (16 kilometers) away.
  • If caught outside away from a building or car, stay clear of water bodies and tall objects like trees. Find a low spot or depression and crouch down as low as possible—but don’t lie down on the ground. Lightning can move in and along the ground surface, and many victims are struck not by bolts but by this current.

google is a miracle (edited post reflecting flea debacle)

how did we manage before google existed? how did we ever find images to put in our power point presentations? how much more tedious was it to find scientific articles when we had only pub med? how else do you find out if the guy you met in that random NYC bar who said he was an "architect" is, in fact, an architect and not an ax murderer?
i challenge any and all readers to honestly say that google has not changed their lives in some meaningful way. how you define meaningful is, of course, up to you.

i published this post this morning, before i realized the maelstrom of scandal going around the blogosphere regarding my friend flea. (hey, i've been on vacation in a place with no internet. yes, places like that do still exist. you just have to drive really far to get there.)

if you have no idea what i'm talking about, check out this post by Adventures of an Awesome (Sometimes) Mother. it has links to both the globe article and the blogosphere response, from both the medical and legal side.

i'm also intrigued by kevin MD's post on your google reputation.

there are many opinions floating around out there about what happened. i'll refrain from giving mine, as i'm not sure more needs to be said. all i will say is that medical blogs are forever changed, for better or worse. flea has left his indelible mark, as he always did and hopefully will do again.