It's that time of year again. Time for the in-training exam. Here are my review notes for this year, updated as I compile them. Originally posted to Google Docs but there is a 500 KB limit on files. Re-posted to my drop. If you would like to contribute, comment.
There is nothing quite like watching surgery, as viewers of Gray's Anatomy will agree.
However, when the surgery is on yourself, and you happen to be having open heart surgery and you happen to be awake the whole time, I am not sure I would agree. This study, from Italy, examines the outcome of patients who undergo open-heart surgery while on cardiac bypass, while awake. Awake bypass surgery has actually been around for several years, first performed in the UK in 2003, first performed in the world in 1998, and in the USA in 2000. To watch an operation, check it out here. It's not quite like this dramatization, in which a talk show participant takes out his own heart.
So, the eternal kvetching point for patients exposed to ultrasound in the Emergency Department is, oooooh, "that ultrasound gel is cold".
I wondered why it feels so cold when it is kept at room temperature? For that matter, why can you touch a blanket when it is at room temperature, and it does not feel cold, whereas a stethoscope, or a metal counter may feel cold.
What is it about the sensation of cold that makes some things which may be 78 degrees seem freezing when your body is at 98 degrees, yet when the temperature of the air is 78 degrees you do not feel cold?
And as another question, does this have any diagnostic significance? Does a patient's response to cold indicate anything clinically? There are conditions with weird temperature findings, so-called hot cold reversal or dysesthesia. For example, ciguatera is a condition in which involved seafood can contain ciguatoxin, which can cause strange neurologic findings, including hot cold reversal.
I went back into the advanced thermodynamics and sensory physiology of my youth and looked all this up...hmmm. Didn't find much.Probably something to do with the specific heat of a substance.
Apparently there is something which scientists are calling the menthol receptor. There is even a knockout mouse!
However, you can actually purchase ultrasound gel warmers. Now that is a posh ER that has those!
Most days I take the D, N or Q train across the Manhattan bridge from Brooklyn to Manhattan. This is an excellent time to check your email, send a text message, or just take in the view.
The pic above is of a boat named for PO Scarangella, taken by "Tom Hoboken", from flickr.
One morning, I happened to have actually had a cup of coffee prior to getting on the train, and was looking at the wonderful view of lower Manhattan across to the Brooklyn bridge when I saw the harbor police boat... The police officer appeared to be throwing something overboard, perhaps an anchor... The boat appears to be there every morning, and it seems like it would be a wonderful job- to be paid to sit on a boat in the morning and watch the sunrise and just hang out with the waves rocking against your boat...then I thought about it some more, since my secret ambition apart from working an emergency department would be to save lives on the water... What does the harbor patrol officer do?
Is this part of the counter-terrorism effort? Does this boat come to the assistance of people who fall off ferries? Shouldn't the Coast Guard be doing this instead of interdicting drug traffickers? Then the terrible thought crossed my mind.. do they look for jumpers ? Are they paramedics, all set up to intubate the jumper with signs of life? Do they do chest tubes for the inevitable pneumos and have a thoracotomy set up?
I did a little research, and found the story of a woman who apparently jumped from the bridge and was rescued, a Boston paramedic assigned to harbor patrol who hilariously tells the story of a Chinese sailor talking back to Coast Guard dispatch, "never mind color of boat! halfway down!,you come now!", a feral cat rescued from a liveaboard boat by a California harbor patrol, a story about a man who jumped off a gay pride party yacht and was then shot and killed after scuffling with harbor police after his rescue, a story about a beaver rescued from the East River while Harbor Police were on patrol during the Pope's visit to NYC, and a piece about kayakers who got too close to the waterfalls and had to be pulled out of the East River, and the interdiction of drug smugglers by police divers who have been known to sleep in the rudder compartment of cargo ships.
So that's what they do!
While looking around, I found an impressive collection of photos of water traffic in this blog about New York Harbor...
So it is exceedingly cold now in New York, and most likely for this reason, a mouse appeared in my house. Now, the ecology of urban living is most interesting. I have noticed in the past few days a peculiar smell in the local bodega, it smells like cat piss. Now, this is the whole reason I started going to this Bodega, because it did not smell like either cat piss or gas from the gas refrigerators. So I asked the staff in the bodega and they said they had a cat, but that they have not seen the cat in a while... so perhaps the street cats are pissing in the bodega because it is so cold outside... I will be most happy when the street cats learn to use a litter box.
A concise listing of things to know about shock, hopefully to be updated frequently.
Shock is defined as inadequate perfusion to meet the needs of tissue metabolism.
Shock can be compensated or decompensated.
Decompensated shock is defined as shock plus systolic hypotension, or
IF BP is unmeasurable, defined as absent distal pulses, prolonged capillary refill, cool extremities, tachycardia, altered mental status (decreased level of consciousness/responsiveness)
Maximum allowable heart rates.
newborn-to 3 months- 85-205.
3 months to 2 yrs- 100-190.
2 yrs to 10 yrs 60-140.
>10 yrs 60-100
MINIMUM acceptable blood pressures
below 12 hours of life and less than 1 kg of weight. 39 systolic.
12 hours of life, 3 kg neonate- 50 systolic
neonate- 96 hours of life- 60 systolic.
Infant- 1 month to 1 year- 70 systolic.
child from age 1-10 =[70 + (2x age in years)]
child age 10 plus= 90 systolic
Criteria for dehydration in children.
minimal (<5%)dry MM, plus or minus tachycardia plus or minus decreased UO.
there will be NO depressed fontanelle, sunken eyeballs, abnormal turgor, cap refill prolonged, weak pulses, hypotension, hyperpnea, altered mental status, or acidosis.
moderate (5-10)positive for dry mm, tachy, depressed fontanelle, sunken eyeballs, decreased uo, PLUS or MINUS turgor, altered, acidosis.
severe (>10) requires weak peripheral pulses, hypotensions, hyperpnea, altered mental status, acidosis, high urine sp grav.
class 1,2,3,4 hemorrhage
class 1-
up to 750 mL blood loss, pulse less than 100, normal BP, normal or increased pulse pressure, rr 14-20, UO >30 mL/hr (0.5 ml/kg), slightly anxious mental status, replace with 3:1 crystalloid:blood.
class 2-
up to 1500 mL blood loss, pulse >100, normal BP, decreased PP, RR 20-30,UO 20-30,mildly anxious. replace with 3:1 cystalloid:blood.
class 3-
up to 2000 mL blood, pulse >120, decreased BP, decreased PP, RR 30-40, UO 5-15, anxious/confused, replace with crystalloid and blood.
class 4
>2000 mL blood, pulse >140, decreased BP and PP, RR >35, negligible UO, confused/lethargic, replace crystalloid and blood.
Metabolism generates ATP which keeps biological membranes intact and functioning (brain and cardiac).
ATP can be generated through anaerobic and aerobic metabolism.
Although seemingly logical, ATP cannot be injected directly into a tissue to improve performance, for a variety of reasons. British Journal of Anaesthesia 94 (5): 556–62 (2005)
http://bja.oxfordjournals.org/cgi/reprint/94/5/556
Anaerobic glycolysis does not require oxygen or mitochondria, it occurs in the cytoplasm. It generates lactate and acid as a byproduct, leading to lactic acidemia.
Aerobic metabolism requires oxygen and the electron transport chain of the mitochondria, it takes longer than anaerobic glycolysis.
For perfusion to occur, cardiac output must be maintained, which requires heart rate and stroke volume. CO=HRxSV
trauma activation
ejection from auto
death in compartment
pedestrian thrown or run over
speed > 40 mph
deformity >20 inches
intrusion > 12 inches
extrication >20 min
fall >20 ft
rollover
auto vs pedestrian >5 mph impact
motorcycle > 20 mph or separation of rider and bike.
flail chest
two or more prox long bone fx
amputation proximal to wrist/ankle
pen trauma to head, neck, torso, extrem prox to elbow and knee
open and depressed skull fx
limb paralysis
pelvic fx
combo trauma plus burn
major burn
My hiatus from blogging of late has been more to do with commuting to Elmhurst than with an absence of things to say... The empty stretchers are how I like to leave the ER every morning, the sunflowers welcome me home, and the waterfalls mark the ebb and flow of each day. Poetic, hmmm? 
