R4 Case Follow Up with Dr. Boyer
Middle aged female presents with an occipital headache, abrupt in onset, nausea but no vomiting.
Vital Sings: BP 130/105; P 84; 100%; RR 18; Afebrile
On head CT found to have a perimesencephalic bleed (non-aneurysmal SAH)
- Perimesencephalic bleeds compose 10% of SAH
Diagnosis of SAH more generally:
- 1st degree relative with history of aneurysmal bleed
- Heightened activity at onset of headache
- Altered Mental Status
- Persistent Vomiting
Within 6 hours of onset of suspected SAH, is non-contrast head CT sufficient?:
- Perry et al. Sensitivity of computed tomography performed within six hours of onset of headache for diagnosis of subarachnoid hemorrhage: prospective cohort study. BMJ 2011;343:d4277.
- Suggests that there is sufficient sensitivity of 3rd generation CT scanners in ruling out SAH within 6 hours of HA onset
If outside that window and proceeding to LP, what is the criteria for SAH?
- Perry et al. Differentiation between traumatic tap and aneurysmal subarachnoid hemorrhage: prospective cohort study. BMJ 2015;350:h568.
- Tube 4: <2,000 RBC and NO xanthochromia = 100% sensitivity for SAH
Can a traumatic tap go home?
- Gorchynski et al. Interpretation of Traumatic lumbar punctures in the setting of possible subarachnoid hemmorhage: Who can be safely discharged?
- 30% clearance between tubes 1 and 4
- Consider SAH ruled out of RBC in tube 4 <500
What is the sensitivity of CT angio for aneurysm <3mm?
An EBM Sepsis Discussion with Dr. Baez and Dr. Summers
- 1 million patients/year suffer from sepsis
- 5.2% of all healthcare dollars are related to sepsis care
Sepsis 3 definitions:
- Sepsis: life threatening organ dysfunction caused by dysregulated host response to infection
- Severe sepsis is no longer a thing!
- Septic shock: a subset of sepsis in which profound circulatory, cellular and metabolic abnormalities are associated with a greater risk of mortality than with sepsis alone
- Byproduct of pyruvate being shunted to LDH in anaerobic metabolism (probably)
- Nguyen et al., in Crit Care Med 2004, found a 10% lactate clearance at 6 hours in sepsis decreased mortality by 11%.
- Jones et al., in JAMA 2010 found that lactate clearance was non-inferior to ScvO2 monitoring for mortality in sepsis
- Marik & Bellomo in Anesthesiology, Perioperative and Crit Care Med question the etiology of lactate in sepsis, however, arguing that a catecholamine surge is responsible for lactate production. If this is the case, lactate clearance merely signifies an attenuation of the stress response, and should not be a marker of resuscitation
- Numerous studies do show, however, that an elevated lactate is associated with increased mortality broadly
- Seymour et al in their Sepsis 3 definitions discuss qSOFA as a validated scoring system of septic patients in the ICU identifying those with increased mortality risk
- Boyd et al in Crit Care Med 2011 suggest that more than 3L of fluid resuscitation at the 12 hour mark may result in increased mortality
Predicting Fluid Responsiveness
- The current state of the literature appears to suggest that Echocardiography in trained hands is likely the most robust static assessment of fluid responsiveness available in the ED.
- Multiple dynamic indices of fluid responsiveness exist, including:
- Pulse pressure variation
- >12% yields good Sn and Sp for fluid responsiveness
- Caval index - change in IVC diameter throughout the respiratory cycle
- >18% generally indicates fluid responsiveness
- Passive leg raise - used on conjunction with the NICOM device
- Well validated against the gold standard of transpulmonary thermodilution
- Can measure increase in CO with a simulated ~500cc bolus of fluid from the legs
- All ED indices generally rely on patient being in NSR; mechanical ventilation with no spontaneous effort; a TV greater than 8cc/kg; and normal chest wall compliance
- Pulse pressure variation
Iatrogenic Toxicology with Dr. Gauger
Neuroleptic Malignant Syndrome
- Idiosyncratic reaction, we can not predict when or where it will occur
- It is, however, typically during initial phase of treatment
- Usually young to middle aged males
- Any antipsychotics can cause this (higher incidence with 1st generation)
- 0.2-1.4% prevalence amongst patients on antipsychotics, and carries a 4-12% mortality
- Clinically patients are:
- Rigid (lead pipe) - generalized and symmetric
- Hyperthermic - not responsive to antipyretics
- Autonomic dysfunction - tachy, labile hypertension
- High CK, leukocytosis, and normal CSF studies are common
- Tx: discontinue all neuroleptics, consider intubation with non-depolarizing agents, CCB for hypertension, actively cool
- Dantrolene - causes muscle relaxation by inhibiting calcium release
- Bromocriptine - dopamine receptor agonist
Acute Dopamine Depletion Syndrome
- Clinically identical to NMS, but occurs in Parkinson's Disease patients who do not receive their medications
- Tx is the same as NMS, in addition to repleting their Parkinsons medications
- Neuromuscular hyperactivity - specifically clonus (spontaneous or induced)
- Altered mental status
- Sympathetic activation
- Supportive - fluids, antipyretics, respriatory support
- Cyproheptadine - antiserotonergic and antihistaminergic properties
- Often caused from decreased GFR, volume depletion, abnormal thyroid fx (both hyper and hypo)
- Patients present with AMS, renal failure, and electrolyte derangements
- Lithium toxicity is a clinical diagnosis, and Li levels do not correlate to severity (the whole body LI load is clinically more important than a single serum measurement acutely), higher levels are more concerning in acute overdose as it takes hours/days to equilibrate with the CNS
- Management includes:
- Whole bowel irrigation if acute
- IV hydration
- Electrolyte repletion
- Phenytoin is 90% albumin bound, so changes in serum albumin can change free levels even in a stable dose, causing toxicity
- At higher levels of toxicity, elimination becomes 0 order, and half life can approach 60 hrs
- Patients present with cerebellar signs (nystagmus, ataxia, dysarthria), behavioral changes, confusion, hallucinations, hyperreflexia
- Chronic phenytoin elevations can cause gingival hyperplasia, frontal bossing, agranulocytosis, hepatotoxicity
- Workup includes total phenytoin level and albumin (free levels will not return in real time)
- Tx is supportive, but activated charcoal can be considered in acute overdoses, and hemodialysis can be beneficial, but is generally not necessary.
Trauma Pearls with Dr. Axelson
VBG Correlation with ABG
- Emerg Med J 2007; 24:569-571 and Respirology 2014; 19:168-175
- Demonstrate that PO2 on a peripheral VBG has no correlation to O2 on a VBG
- pH on a VBG will be within 0.03 and 0.04 of ABG pH
- Bicarb on a VBG will be within about 5 of arterial bicarb
- VBG pCO2 of 45 and below has been shown to have 100% for ruling out hypercarbia
Indications for the FAST exam on a trauma patient
- FAST was designed to replace the DPL, and it's use is indicated as a triage tool for the hemodynamically unstable blunt trauma patient
- Speficity of FAST for blood in the peritoneum/visceral organ injury is ~99%
- Sensitivity of FAST in this setting is only 40%
- FAST rules things IN, it rules nothing OUT
Pulses, their correlation to BP with a touch of dogma
- Historical teaching indicates that the presence of a carotid, radial, and femoral pulse corresponds to a SBP >80 mmHg in a trauma patient, with loss of femoral pulse corresponding to a BP >70, loss of femoral and radial corresponding to SBP >60 mmHG
- According to an article in BMJ 2000; 321(7262):673-674, this pulse estimation of SBP was innacurate in 24/28 trauma patients, almost always underestimating.
Pediatric Emergency Medicine Sim
7yo F o/w healthy presents to the community with cough/fever/difficulty breathing. Seen at urgent care 3 days ago for fever and cough. CXR at the time revealed ?R sided pneumonia, so given amoxicillin and sent home. She presents today for worsening symptoms.
- Vitals: T 38.9; P 160; R 55/83% RA; BP 88/49
- Exam: Awake, alert, nasal congestion and decreased breath sounds in RLL noted with diffuse wheezing, 2/6 systolic ejection murmur heard. No rashes. Normal abdominal exam. Looks pale but not cyanotic.
- Influenza, pneumonia, endocarditis, reactive airway disease, cardiogenic shock from myocarditis
- CXR: RLL pneumonia with likely associated effusion
- Labs: 7.27/48/16/-6; lactate 3.6; Hgb of 9 and platelets of 68; Cr 0.86; glucose 230
- Tx: 10cc/kg bolus, early antibiotics to include Ceftriaxone for GN coverage, and Vancomycin for MRSA coverage in this ill patient, tylenol for fever, and this patient needs intubation
- Influenza rapid swab returns +Influenza B
- She requires 60cc/kg of fluid before BP stabilization
- After 2nd 20cc/kg bolus, at least consider Epi as a first line pressor
- Intubated with Ketamine and succ
- worsening oxygenation and ventilation in PICU
- VV ECMO, converted to VA ECMO, remains on ECMO in CICU
- Beware of flu and superimposed pneumonia!
3yo M presents to the community with fever and congestion. He was born at 34wks, NICU stay, and has been doing well since discharge. No travel, no vomiting or diarrhea.
- Vitals T 39.1; P 176; R 42 94%/RA; BP 110/66
- Exam: Awake, ill appearing, making tears and rhinorrhea noted, tachy with no murmur, cap refill 4seconds and mottling noted, decreased air exchange on R lung base, belly breathing noted
- Ddx: Influenza, pneumonia, reactive airway disease (not bronchiolitis over 2), myocarditis
- VBG 7.34/42/22/-1; WBC 16, 76% segs
- CXR with RLL lobar pneumonia
- Po high dose amox or IV ampicillin is 1st line for immunized CAP (to age 18)
- Unimmunized or chronic health concerns, go to ceftriaxone for broader coverage
- With bolus, IV dose ampicillin, HR normalized and patient perked up, f/u with PMD
- Strep pneumo most common source of CAP
3 mo former 30 wker presents with cough, cyanosis with feeds, difficulty breathing.
- Vitals: HR 150s; BP 60/30s; RR 66 89% with supplemental bagging; T 37.6
- Labs 7.18/68/10/-14 Lactate 2.1, Sodium 133; Potassium 6.2, Glucose 49, Cr 0.3
- V/Q mismatch is most common cause of persistently low sats
- Shunt is another consideration
- Hypoventilation is another consideration
- High Flow nasal cannula: warmed, humidified O2 delivered via nasal cannula at higher flow than standard nasal cannula O2. It remains questionable whether HFNC actually transmits some degree of PEEP to the alveoli.
- Works via washout of nasopharyngeal deadspace resulting in increased O2 fraction in the alveoli
- Reduces inspiratory resistance and work of breathing by providing adequate flow
- Thus far there has been no mortality benefit demonstrated with HFNC
- HFNC may reduce intubation rates in young children, and is overall well tolerated