Grand Rounds Recap - 3/4/2014

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IABP With Dr. Wojciechowski

Case courtesy of Dr Frank Gaillard, http://radiopaedia.org/ From the case "Intra-aortic balloon pump and ICU lines"

Case courtesy of Dr Frank Gaillard, http://radiopaedia.org/ From the case "Intra-aortic balloon pump and ICU lines"

  • What is it? It's a ~10cm long intravascular balloon that inflates with 25-50ml of helium gas during diastole to increase the coronary perfusion pressure and decrease the afterload on the heart (coronary perfusion pressure = diastolic blood pressure - left ventricular end diastolic blood pressure). The catheter itself has a pressure transducer and a catheter that shuttles the helium gas.
  • Why helium? it is low density, metabolically inactive, and dissolves in blood in case the balloon were to rupture.
  • Who gets one? In general they are reserved for hemodynamically unstable patients as salvage therapy (STEMI with cardiogenic shock, acute MI that can't be reperfused, high risk CABG, failed maximal medical therapy).
  • Since the balloon can be a nidus for thrombus formation, patients require anticoagulation if on any setting other than 1:1.
  • Where should it go? The tip should be 2cm distal of the left subclavian.
  • How does it know when to trigger? The device can trigger based on ECG timing (inflation in the middle of the T-wave; deflates when peak R wave is sensed), pressure tracing (inflating at the dichrotic notch), based on pacemaker firing or manual modes. For the most part, the console wants to be in automatic mode and it will pick the trigger that is resulting in the best capture and tracing. 

Toxidromes with Dr. Connell

Toxidrome is the constellation of signs/symptoms resulting from an exposure

General approach to all patients: ABCs, EKG, history, vital signs, glucose, physical exam (mental status, pupils, skin, GI, GU)

  • Opioid toxidrome: miosis, somnolence, decreased respiratory rate. Can be seen in afrin or visine ingestions in addition to common opiods. Keep the naloxone doses small and remember that the goal is adequate ventilation. Naloxone increases SVR which is thought to be the mechanism that induces pulmonary edema. 
  • Sympathomimetic toxidrome: tachycardia, hypertension, mydriasis, agitation/hallucinations, diaphoresis, hyperthermia due to increased release of dopamine, norepi, and epi. Can be caused by amphetamines, bath salts, cocaine, caffeine. EtOH or benzo withdrawls can be mimics. Management is supportive with the main focus on active cooling for hyperthermia (antipyretics will not help) and benzos for agitation. 
  • Anticholinergic toxidrome: mydriasis, flushed skin, dry mucous membranes, hyperthermia, delirium, urinary retention. Caused by antihistamines (especially first generation H1 blockers), jimson weed, atropine, TCAs, atypical antipsychotics. Treatment: supportive care with cooling, benzos, IVF for rhabdo. Physostigmine (0.5-2mg over 5-10min) can be used if severe symptoms or benzos don't improve delirium.
  • Cholinergic toxidrome: diarrhea, urination, miosis, bronchorrhea, emesis, lacrimation, salivation, fasiculations, weakness. Caused by organophosphates, carbamates, physostigmine, liquid nicotine, nerve gas agents. Treatment: airway protection, decontamination, atropine, pralidoxime. 

Case Follow-Ups

Dr. Devries

47yo F with h/o IVDU, recent pericarditis, presents with CP and SOB found to have a large saccular aortic mycotic aneurysm caused by MSSA endocarditis. Mycotic aneurysms can be seen in all areas of the vascular system but are rare in the setting of appropriate antibiotic use. 

Dr. Mann:

50yo M with asthma, tobacco use, schizophrenia who arrives satting 85% and admits to recently smoking crack. Crack lung is an acute pulmonary syndrome with hypoxia, cough, fever, hemotysis, pruritis, pulmonary/alveolar hemorhage. Symptoms worse in those with asthmatics resulting from bronchospasm/constriction. Imaging can show prominent vasculature and ground glass (tree and bud on CT). Treatment is with systemic steroids, bronchodilators, supportive care, usually reverses within 24 hours. 

Dr. Latimer:

50yo AA F with EMS call for respiratory distress who arrives with CPR in progress. Intubated and found to have shark-fin appearance on EtCO2 and treated aggressively for likely asthmatic respiratory arrest with:, magnesium, IVP ketamine, albuterol in addition to standard code drugs. Despite ROSC, she re-arrested and was found to have bilat pneumothoraces with tamponade which was iatrogenic due to a PEEP valve being placed post-intubation. 

Anemia with Dr. Polsinelli

10-25% of patients in the ED are anemic. In younger women it is due to mentruation, older men due to peptic ulcer disease, nursing home residents due to chronic disease. 

  • History: new vs chronic, tarry stools, menstruation, malignancy, nutrition, family history, rashes.
  • Physical exam: look for pallor, scleral icterus, lymphadenopathy, CHF
  • Labs: look at the extra markers from your CBC. MCV is the average volume of each RBC (low in nutritional deficiency or chronic disease, high in B12 deficiency, alcoholism, hypothyroidism). MCH is the amount of Hgb in each cell; if low then it is likely a hypochromic anemia like iron deficiency or thalacemia. MCHC - mean corpuscular Hgb concentration (this is more helpful than MCH). RDW - RBC distribution width which helps to point to marrow quality. 

Open Mic Bullet Points

  • Artificial urethral sphincter - balloon is in the bulbar urethra and pump is located in the scrotum. In the setting of acute urinary retention, you can pump the pump or disable it altogether to allow release of urine. Do not place a foley catheter. 
  • CT scan for dissection in the setting of the acutely elevated Cr. There are other options of IV contrast agent that may be usable despite an elevated Cr if you discuss with radiologist first. 
  • Pneumoperitoneum - if lots of air under the diaphragm it is usually caused by diverticular rupture rather than duodenal/gastric ulcer. 
  • Ketamine can be used for post-intubation sedation on AirCare
  • One minute preceptor model: get a commitment, probe for evidence, teach one rule, tell them what they did well, tell them what they can do better next time.