A family practice physician in rural Maine obtains a blood sample, isolates the RBCs, removes the antibodies and adds antihuman globulin. He note that the erythrocytes aggregate. How would you interpret these results? A. Negative direct Coombs test B. Positive indirect Coombs test C. Colonic adenocarcinoma D. Negative indirect Coombs test E. Positive direct Coombs test
The patient in question has a hemoglobin value of 7.4 g/dL and an elevated serum unconjugated bilirubin. Which is the likely diagnosis? A. Paroxysmal nocturnal hemoglobinuria B. Traumatic hemolysis C. Hereditary elliptocytosis D. Systemic lupus erythematosus E. Erythroblastosis fetalis
Both E
Both direct and indirect tests are antigen-antibody reactions. Differences:
Direct Coombs Test
Uses patient’s RBCs, which are washed clear of plasma, and then incubated with a known antibody.
If they agglutinate, then the direct test is positive.
Test for autoimmune hemolytic anemia
Indirect Coombs also tests for a reaction, but
Uses patient’s serum (not rbcs).
Patient’s serum is added to rbcs that are known to have a certain antigenicity.
If the serum contains the suspected antibodies, then there will be a reaction, and the test is positive.
Screen pregnant women for the presence of antibodies that could cause hemolytic disease of the newborn.
It is also used in cross matching blood before transfusion.
direct—-rbc already have attached antibody..only add anti human ig indirect-to test for antibody—add rbc to the serum,n then add anti human ig
Coombs test (aka Coombs’ test, antiglobulin test or AGT) refers to two clinical blood tests used in immunohematology and immunology.
Direct Coombs test (aka s direct antiglobulin test or DAT) Indirect Coombs test (aka indirect antiglobulin test or IAT)
The direct Coombs test is used to detect red blood cells sensitized with igG alloantibody, IgG autoantibody, and complement proteins. It detects antibodies bound to the surface of red blood cells in vivo. The red blood cells (RBCs) are washed (removing the patient’s own plasma) and then incubated with antihuman globulin (also known as “Coombs reagent”). If this produces agglutination of the RBCs, the direct Coombs test is positive.
The indirect Coombs test is used in prenatal testing of pregnant women, and in testing blood prior to a blood transfusion. It detects antibodies against RBCs that are present unbound in the patient’s serum. In this case, serum is extracted from the blood, and the serum is incubated with RBCs of known antigenicity. If agglutination occurs, the indirect Coombs test is positive
I’m on cardiology right now, and yesterday the fellow taught us some basics for interpreting EKGs. The trick is the have a thorough algorithm and do it every time so you don’t miss anything.
Disclaimer: Obviously this is just a cursory intro so folks won’t look like complete fools like me- who, when asked to interpret an EKG, went into a cold sweat and said, “Well, it looks like the heart is beating.” Attendings do NOT like that.
INTRO
This is what a normal lead II EKG one beat reading should look like. TAKE NOTE LITERALLY EVERYONE STOP CALLING YOUR SQUIGGLY LINES HEARTBEATS IT IS WRONG GAAAHHHH.
Normal EKG.
What the various leads are monitoring.
1. Rhythm: Sinus or not- aka, is the SA node talking to the AV node correctly? Check in leads V1 and II- if there is a P wave before every QRS you have sinus rhythm. If this is not the case, you do not have sinus rhythm! A whole discussion on things messing up sinus rhythm will come when I have a better grip on it myself.
2. Rate: How fast is the heart beating- aka, how fast are the ventricles depolarizing? So EKGs are little tiny boxes in bigger boxes, right? There are several methods for calculating rate using the boxes, but the one that works for my brain is to count the big boxes between R’s and divide that by 300. So, 1 big box between R = 300/1 = 300 bpm. 2 big boxes between R= 300/2= 150 bpm. And so on.
In general, any heart rate above 100 is tachycardia, and any heart rate below 60 is bradycardia. These values may vary (ex: SIRS criteria counts heart rate above 90 as tachy). Normal heart rate is around 75 (exceptions include athletes- look up athletic heart syndrome)
3. QRS Complex: Wide or narrow- aka, is the Bundle of His bossing the ventricles around? Basically, a nice narrow QRS complex generally indicates the bundle of His is intact and operating how it is supposed to. A wide QRS complex indicates something is awry with the Bundle of His- could be an organic pathology, could be a medication side effect (ex: antiarrythmics, TCAs, quinidine, to name a few), could be an electrolyte imbalance (ex: hyperkalemia), could be other things.
4. Axis: Is the heart depolarizing the way it should- aka right shoulder to left nipple. I, personally, am still sorting out the axis system, and it’s hard to do in this format. The first, most basic place to start is checking if lead I and aVF are POSITIVE, meaning their QRS complexes go ABOVE the isoelectric line. If that is the case, you are probably ok axis-wise.
Essentially, lead I’s vector goes from left to right, and aVF’s vector goes from head to toe. So the average of those vectors is the general path of depolarization of the heart. You want the axis to be between -30 and +90. So, if aVF is positive, but lead I is negative (the QRS is below the isoelectric line) that means it is going from left to right instead and would be classified as a right shift. Likewise, if lead I is positive, but aVF is negative, that means it is going down to up and would be classified as a left shift. There is soooo much more to axis interpretation, this is just a starting point.
5. Intervals: Again with the conduction system, it’s, like, totally important that it obeys all the rules every time. PR= <.2 seconds, or one big box QRS= <.12 seconds, or 3 small boxes QT= < ½ the RR interval
6. ST segment changes: checking for CAD- aka, is the myocardium getting enough blood/oxygen? Since the folks in the South seem to consider butter a food group and know that if it can’t be fried it’s not worth eating, CAD is a huuuuuuuuge issue here. When blood supply to the myocardium is compromised, there will usually be characteristic EKG changes. Note- not every episode of angina/MI will have EKG changes though! - Inferior leads —> right coronary artery. - lateral leads —> circumflex artery - anteroseptal leads —> left anterior descending. Disclaimer: does not apply to everyone all the time, some folks have variant coronary anatomy.
So the EKG changes to look for must be seen in two contiguous leads, aka, two inferior leads or two lateral leads. - Ischemia (low oxygen) = ST depression or T wave inversion (EXCEPT T wave inversions are ok in leads V1 and aVR)
- Injury = ST elevation
- Old infarct/dead myocardium = pathologic Q waves. Basically that first negative vector (aka, the Q of the QRS complex) should never be bigger than one tiny box.
And, that, friends, is a basic algorithm for reading EKGs! There is a lot more, but if you follow these steps every time, you will look like a rock star on wards. Good luck!
Usually, I lie. At a party, someone asks the question. It’s someone who hasn’t smelled the rancid decay of week-dead flesh or heard the rattle of fluid flooding lungs. I shake the ice in my glass, smile, and lie. When they say, “I bet you always get that question,” I roll my eyes and agree.
There are plenty of in-between stories to delve into; icky, miraculous ones and reams of the hilarious and stupid. I did, after all, become a paramedic knowing it would stack my inner shelves with a library of human tragicomedy. I am a writer, and we are nothing if not tourists gawking at our own and other people’s misery. No?
The dead don’t bother me. Even the near-dead, I’ve made my peace with. When we meet, there’s a very simple arrangement: Either they’re provably past their expiration date and I go about my business, RIP, or they’re not and I stay. A convenient set of criteria delineates the provable part: if they have begun to decay; if rigor mortis has set in; if the sedentary blood has begun to pool at their lowest point, discoloring the skin like a slowly gathering bruise. The vaguest criterion is called obvious death, and we use it in those bizarre special occasions that people are often sniffing for when they ask questions at parties: decapitations, dismemberments, incinera- tions, brains splattered across the sidewalk. Obvious death.
One of my first obvious deaths was a portly Mexican man who had been bicycling along the highway that links Brooklyn to Queens. He’d been hit by three cars and a dump truck, which was the only one that stopped. The man wasn’t torn apart or flattened, but his body had twisted into a pretzel; arms wrapped around legs. Somewhere in there was a shoulder. Obvious death. His bike lay a few feet away, gnarled like its owner. Packs and packs of Mexican cigarettes scattered across the highway. It was three a.m. and a light rain sprinkled the dead man, the bicycle, the cigarette packs, and me, made us all glow in the sparkle of police flares. I was brand new; cars kept rushing past, slowing down, rushing past.
Obvious death. Which means there’s nothing we can do, which means I keep moving with my day, with my life, with whatever I’ve been pondering until this once-alive-now-inanimate object fell into my path.If I can’t check off any of the boxes—if I can’t prove the person’s dead—I get to work and the resuscitation flowchart erupts into a tree of brand-new and complex options. Start CPR, intubate, find a vein, put an IV in it. If there’s no vein and you’ve tried twice, drill an even bigger needle into the flat part of the bone just below the knee. Twist till you feel a pop, attach the IV line. If the heart is jiggling, shock it; if it’s flatlined, fill it with drugs. If the family lingers, escort them out; if they look too hopeful, ease them toward despair. If time slips past and the dead stay dead, call it. Signs of life? Scoop ’em up and go.
You see? Simple.
Except then one day you find one that has a quiet smile on her face, her arms laying softly at her sides, her body relaxed. She is ancient, a crinkled flower, and was dying for weeks, years. The fam- ily cries foul: She had wanted to go in peace. A doctor, a social worker, a nurse—at some point all opted not to bother having that difficult conversation, perhaps because the family is Dominican and the Spanish translator wasn’t easily reachable and anyway, someone else would have it, surely, but no one did. And now she’s laid herself down, made all her quiet preparations and slipped gently away. Without that single piece of paper though, none of the lamentations matter, the peaceful smile doesn’t matter. You set to work, the tree of options fans out, your blade sweeps her tongue aside and you battle in an endotracheal tube; needles find their mark. Bumps emerge on the flat line, a slow march of tiny hills that resolve into tighter scribbles. Her pulse bounds against your fingers; she is alive.
But not awake, perhaps never to be again. You have brought not life but living death, and fuck what I’ve seen, because that, my friends at the party, my random interlocutor who doesn’t know the reek of decay, that is surely one of the craziest things I have ever done.
But that’s not what I say. I lie.
Which is odd because I did, after all, become a medic to fill the library stacks, yes? An endless collection of human frailty vignettes: disasters and the expanding ripple of trauma. No, that’s not quite true. There was something else, I’m sure of it.
And anyway, here at this party, surrounded by eager listeners with drinks in hand, mouths slightly open, ready to laugh or gasp, I, the storyteller, pause. In that pause, read my discomfort.
On the job, we literally laugh in the face of death. In our crass humor and easy flow between tragedy and lunch break, outsiders see callousness: We have built walls, ceased to feel. As one who laughs, I assure you that this is not the case. When you greet death on the daily, it shows you new sides of itself, it brings you into the fold. Gradually, or maybe quickly, depending on who you are, you make friends with it. It’s a wary kind of friendship at first, with the kind of stilted conversation you might have with a man who picked you up hitch- hiking and turns out to have a pet boa constrictor around his neck. Death smiles because death always wins, so you can relax. When you know you won’t win, it lets you focus on doing everything you can to try to win anyway, and really, that’s all there is: The Effort.
The Effort cleanses. It wards off the gathering demons of doubt. When people wonder how we go home and sleep easy after bearing witness to so much pain, so much death, the answer is that we’re not bearing witness. We’re working. Not in the paycheck sense, but in the sense of The Effort. When it’s real, not one of the endless parade of chronic runny noses and vague hip discomforts, but a true, soon- to-be-dead emergency? Everything falls away. There is the patient, the family, the door. Out the door is the ambulance and then farther down the road, the hospital. That’s it. That’s all there is.
Awkward text messages from exes, career uncertainties, generalized aches and pains: They all disintegrate beneath the hugeness that is someone else’s life in your hands. The guy’s heart is failing; fluid backs up in those feebly pumping chambers, erupts into his lungs, climbs higher and higher, and now all you hear is the raspy clatter every time he breathes. Is his blood pressure too high or too low? You wrap the cuff on him as your partner finds an IV. The monitor goes on. A thousand possibilities open up before you: He might start getting better, he might code right there, the ambulance might stall, the medicine might not work, the elevator could never come. You cast off the ones you can’t do anything about, see about another IV because the one your partner got already blew. You’re sweating when you step back and realize nothing you’ve done has helped, and then everything becomes even simpler, because all you can do is take him to the hospital as fast as you can move without totaling the rig.
He doesn’t make it. You sweated and struggled and calculated and he doesn’t make it, and dammit if that ain’t the way shit goes, but also, you’re hungry. And you’re alive, and you’ve wracked your body and mind for the past hour trying to make this guy live. Death won, but death always wins, the ultimate spoiler alert. You can only be that humbled so many times and then you know: Death always wins. It’s a warm Thursday evening and grayish orange streaks the horizon. There’s a pizza place around the corner; their slices are just the right amount of doughy. You check inside yourself to see if anything’s shattered and it’s not, it’s not. You are alive. You have not shattered.
You have not shattered because of The Effort. The Effort cleanses because you have become a part of the story, you are not passive, the very opposite of passive, in fact. Having been humbled, you feel amazing. Every moment is precise and the sky ripples with delight as you head off to the pizza place, having hurled headlong into the game and given every inch of yourself, if only for a moment, to a losing struggle.
It’s not adrenaline, although they’ll say that it is, again and again. It is the grim, heartbroken joy of having taken part. It is the difference between shaking your head at the nightly news and taking to the streets. It’s when you finally tell her how you really feel, the moment you craft all your useless repetitive thoughts into a prayer.
At the party, as they look on expectantly, I draft one of the lesser moments of horror as a stand-in. The evisceration, that will do. That single strand of intestine just sitting on the man’s belly like a lost worm. He was dying too, but he lived. It was a good story, a terrible night.
I was new and I didn’t know if I’d done anything right. He lived, but only by a hair. I magnified each tiny decision to see if I’d erred and came up empty. There was no way to know. Eventually I stopped taking jobs home with me. I released the ghosts of what I’d done or hadn’t done, let The Effort do what it does and cleanse me in the very moment of crisis. And then one night I met a tiny three-year old girl in overalls, all smiles and high-fives and curly hair. We were there because a neighbor had called it in as a burn, but the burns were old. Called out on his abuse, the father had fled the scene. The emergency, which had been going on for years, had ended and only just begun.
The story unraveled as we drove to the hospital; I heard it from the front seat. The mother knew all along, explained it in jittery, sobbing replies as the police filled out their forms. It wasn’t just the burns; the abuse was sexual too. There’d been other hospital visits, which means that people who should’ve seen it didn’t, or didn’t bother setting the gears in motion to stop it. I parked, gave the kid another high five, watched her walk into the ER holding a cop’s hand.
Then we had our own forms to fill out. Bureaucracy’s response to unspeakable tragedy is more paperwork. Squeeze the horror into easy-to-fathom boxes, cull the rising tide of rage inside and check and recheck the data, complete the forms, sign, date, stamp, insert into a metal box and then begin the difficult task of forgetting.
The job followed me down Gun Hill Road; it laughed when I pretended I was okay. I stopped on a corner and felt it rise in me like it was my own heart failing this time, backing fluids into my lungs, breaking my breath. I texted a friend, walked another block. A sob came out of somewhere, just one. It was summer. The breeze felt nice and nice felt shitty.
My phone buzzed. Do you want to talk about it?
I did. I wanted to talk about it and more than that I wanted to never have seen it and even more than that I wanted to have done something about it and most of all, I wanted it never to have hap- pened, never to happen again. The body remembers. We carry each trauma and ecstasy with us and they mark our stride and posture, contort our rhythm until we release them into the summer night over Gun Hill Road. I knew it wasn’t time to release just yet; you can’t force these things. I tapped the word no into my phone and got on the train.
I don’t tell that one either. Stories with trigger warnings don’t go over well at parties. But when the question is asked, the little girl’s smile and her small, bruised arms appear in my mind.
The worst tragedies don’t usually get 911 calls, because they are patient, unravel over centuries. While we obsess over the hyperviolent mayhem, they seep into our subconscious, poison our sense of self, upend communities, and gnaw away at family trees with intergenerational trauma.I didn’t pick up my pen just to bear witness. None of us did. And I didn’t become a medic to get a front-row seat to other people’s tragedies. I did it because I knew the world was bleeding and so was I, and somewhere inside I knew the only way to stop my own bleeding was to learn how to stop someone else’s. Another call crackles over the radio, we pick up the mic and push the button and drive off. Death always wins, but there is power in our tiniest moments, humanity in shedding petty concerns to make room for compassion. We witness, take part, heal. The work of healing in turn heals us and we begin again, laughing mournfully, and put pen to paper.
Daniel José Older
Woah
“I did it because I knew the world was bleeding and so was I, and somewhere inside I knew the only way to stop my own bleeding was to learn how to stop someone else’s”
When I posted this a while ago, I said that you can send me your email if you wanted this chart. Since I’m pretty busy these days, I won’t be able to answer right away. This is why I’m reblogging it with the link to the dirve where you can download it from.
Click HEREand look for the Word Document “Cranial Nerves”
Chest X-rays (aka CXR) are one of the most basic imaging studies done in medicine. Almost every hospitalized patient has one and you will see hundreds of them by the time you finish med school.
But it was be super easy to get distracted by the huge glaring pathology (like a giant mass) that you miss other pathology (like a broken clavicle). So, like with reading EKGs, it’s best to have an algorithm you run through for every CXR so you don’t miss anything.
Disclaimer: Again, this is just a general introduction with some basics to help you start out on wards. There is a lot more to interpreting chest x-rays that what I mention, that is why radiologists are awesome.
First: What is the view- is it AP (front to back) or PA (back to front)? Lateral CXRs are obvious.
PA
AP
If the patient is able to stand, a PA view is generally preferred. AP is generally when patients are confined to the bed- also you usually cannot diagnose cardiomegaly from an AP view because the heart is almost always bigger in this view. How do you tell the difference between them? Look at the scapula- in a PA view the scapula are usually clear of the lungs, whereas in an AP view the two generally overlap. Sometimes the clavicle positioning can be a good clue too- see the differences between the two?
Lateral
Second- what is the quality, because that can have a major effect on your interpretation. A good mnemonic is RIP.
- Rotation - Measure the distance of each clavicle from the spinous processes at that level, if they are equidistant then the patient is not rotated.
- Inspiration - If you can count nine posterior ribs within the lung fields before you reach the diaphragm, then there was enough inspiratory effort. Poor inspiratory effort will look like the patient has an airspace disease. Note: Posterior ribs = more apparent, look more horizontal. Anterior ribs = less visible, 45ish degree angle towards feet
- Penetration - With flawless penetration, you should be able to see the thoracic spine through the heart.
Underpenetration= Left hemidiaphragm and left lung base will not be visible, and pulmonary markings will appear more prominent than they actually are. Ahhhh!!!!
Overpenetration= what is even happening here
OK, now you’re ready to see what is going on with the patient. I suggest the systematic approach, which has the handy mnemonic ABCDE= airway, bones, cardiac, diaphragm, everything else (lungs). I’m not going to go into all the pathology associated with everything, because that would take forever.
- Airway: Is the trachea patent and midline? Can you see the mainstem bronchi and the carina? If there is an endotracheal tube in place, make sure that it is 3-4 cm above the carina. Also check to make sure the mediastinum is not deviated or abnormally wide.
- Bones: Is anything broken or dislocated? Any lytic lesions?
- Cardiac: How clear is the cardiac silhouette? Is the heart enlarged? What about all the vessels- the aorta, SVC, IVC, etc.
- Diaphragm: Is the right side higher than the left but not like wayyyy too much? Are the costophrenic angles clear (if not, could be an effusion!)?
- Everything else: NOW you can look at the lungs. Is there an infiltrate or a mass? What about pneumothorax? Also check for you friendly neighborhood gastric air bubble, it’s supposed to be below the diaphragm.
Fear in a mouse brain looks much the same as fear in a human brain.
When a frightening stimulus is encountered, the thalamus shoots a message to the amygdala — the primitive part of the brain — even before it informs the parts responsible for higher cognition. The amygdala then goes into its hard-wired fight-or-flight response, triggering a host of predictable symptoms, including racing heart, heavy breathing, startle response, and sweating.
The similarities of fear response in the brains of mice and men have allowed scientists to understand the neural circuitry and molecular processes of fear and fear behaviors perhaps better than any other response. That understanding has spurred breakthroughs in treatments for psychiatric disorders that are underpinned by fear.
Anxiety disorders are one of the most common mental illnesses in the country, with nearly one-third of Americans experiencing symptoms at least once during their lives. There are generalized anxiety disorders and fear-related disorders, which include panic disorders, phobias, and post-traumatic stress disorder (PTSD).
Emory psychiatrist and researcher Kerry Ressler is on the front lines of fear-disorder research. In his lab at Yerkes National Primate Research Center, he studies the molecular and cellular mechanisms of fear learning and extinction in mouse models. At Grady Memorial Hospital, he investigates the psychology, genetics, and biology of PTSD. And through the Grady Trauma Project, he works to draw attention to the problem of inner city intergenerational violence.
“If you look at Kerry’s work, it can seem like it’s all over the place — he’s got so many studies going on, and he collaborates with so many other scientists,” says Barbara Rothbaum, associate vice chair of clinical research in psychiatry and director of the Trauma and Anxiety Recovery Program at Emory. “But they are all pieces to the same puzzle. All his work, from molecular to clinical to policy, fits together and starts telling a story.” A Howard Hughes Medical Institute investigator, Ressler was recently elected to the Institute of Medicine — one of the highest honors in the fields of health and medicine. He was named a member of a new national PTSD consortium led by Draper Laboratory. And he recently appeared on the Charlie Rose show’s brain series.
Panic attacks seem to tie the fear-related disorders together, he explained on Charlie Rose. Everyone experiences fear, which evolved as a survival mechanism, but it only rises to a clinical level when people are unable to function normally in the face of it. For instance, PTSD includes not only intrusive thoughts, memories, nightmares, and startle responses, but also the concept of avoidance, which may extend to other areas of the individual’s life.
“There’s a patient I’ve seen who was attacked in a dark alley,” Ressler shared on the show. “Initially it just felt dangerous to go out at night, but after a while she grew afraid of men and couldn’t go to that part of town. Then she couldn’t leave her house, and finally, her bedroom. The world got more and more dangerous.”
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[Download: AB1, AB2, AB3]
[Antibiotic Cheat Sheet]
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“ANTIBIOTICS: COMPLETE CHART
[Download: AB1, AB2, AB3]
[Antibiotic Cheat Sheet]
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“ANTIBIOTICS: COMPLETE CHART
[Download: AB1, AB2, AB3]
[Antibiotic Cheat Sheet]
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