The blog Brown Coat Nation (University of Illinois, Chicago) has a new series entitled “Inconceivable.” The idea is to expose medical terminology that we tend to use incorrectly. The first installment is focused on the misuse of the term “left shift,” and it’s the focus of this FOAMcastini.
The Core Content
The correct use of the term “left shift” refers to the presence of banded (immature) neutrophils in the blood. It does not refer to an elevated white blood cell count with a high percentage of neutrophils. An elevated white blood cell count with an abnormally high percentage of neutrophils should be called “neutrophillic leukocytosis.” Only the presence of immature neutrophils in the periphery (including bands) can accurately be called a “left shift.”
The term “left shift” is derived from the diagrams of the six stages of neutrophil development in the bone marrow. On the far left, you see the most basic precursor: the myeloblast. On the far right of the diagram one finds the mature segmented neutrophil (also known as the “polymorphonuclear leukocyte, or PMN). But just to the left of that is the “banded” neutrophil (the 5th stage of neutrophil development in which the large band of nuclear material has not yet “disbanded” into segments).
When an infection runs rampant, sometimes the bone marrow runs out of mature neutrophils to send to the periphery. So, the marrow panics and releases immature banded neutrophils that normally would not be considered “ready for prime time.”
Here’s some relevant spaced repetition on SIRS: Along with leukocytosis (>12,000) and leukopenia (<4,000), Bandemia >10% is one of the SIRS criteria (Systemic Inflammatory Response Syndrome). Temperature (>38C or <36C), Heart rate >90 (“sirs-ycardia”), tachypnea (RR>20) or PCO2 <32) are the other SIRS criteria. The presence of at least two these categories constitutes “positive SIRS”. In pediatrics, the temperature, heart rate, and respiratory rates should be age-adjusted.
Check out our previous episode on appendicitis for a reminder on whether leukocytosis (with or without neutrophillic predominance) is useful in risk stratification.
The St. Emlyn’s team ran a post on the REVERT trial, which added a new spin to the traditional (and traditionally ineffective) Valsalva maneuver for stable supraventricular tachycardia (SVT). In this post, Dr. Rick Body goes through the trial covering not only the results but also drops pearls on methodology.
Randomized 433 patients with SVT to one of the following:
“Modified” Valsalva maneuver: patient sitting up performs Valsalva using a syringe to maintain 40 mm Hg for 15 sec and then placed supine with passive leg raise immediately after procedure (see video)
“Standard” Valsalva maneuver: patient sitting up performs Valsalva using a syringe to maintain 40 mm Hg for 15 sec while maintaining upright position
43% of the patients in modified Valsalva group versus 17% in the standard technique achieved sinus rhythm at one minute yielding an absolute risk reduction of 26.2% (p<0.001) with a number needed to treat of about 4 (3.8).
Core Content – Supraventricular Tachycardia (SVT) and Ventricular Tachycardia (VT)
Tintinalli (7e) Chapter 22; Rosen’s Emergency Medicine (8e) Chapter 79
Broad term referring to tachycardias originating above the ventricles, including the regular rhythms of sinus tachycardia, AV nodal reentrant tachycardia, AV reentrant tachycardia, and the irregular rhythms of multifocal atrial tachycardia, atrial fibrillation, and some forms of atrial flutter.
Unstable patients – electrical cardioversion at 0.5-1 J/kg (100J for an adult) + ABCs!
Valsalva maneuver – we like this method of having a patient blow on a syringe. Unfortunately, prior to the REVERT trial, the valsalva maneuver success rate has been documented ~19% .
Adenosine (0.1mg/kg or 6 mg in adult; 2nd dose 0.2 mg/kg or 12 mg in adult, with occasional dose adjustments) – administration can be tricky because of the drug’s short half life, necessitating proximal administration, elevation of the arm, and a quick saline flush afterwards. You can combine the adenosine IN the flush as detailed in this post, meaning no stopcock.
Calcium channel blockers or beta-blockers (verapamil, diltiazem or even metoprolol, esmolol) – Recently the calcium channel blockers have increased in popularity in the FOAM world and these are Rosenalli approved [4,5].
Diagnosis: Typically wide QRS complex (95% with QRS >120 ms) and fast (150-200 beats per minute).
SVT with abberency can have a wide complex but this should be treated as VT [4,5] (see this video)
Monomorphic – complexes have same morphology
Polymorphic – complexes of various morphologies, associated with poor prognosis [4,5]
Unstable patients – electrical cardioversion at 0.5-1 J/kg (100J for an adult) + ABCs!
Stable patients with monomorphic VT–
Procainamide – Level B recommendation for first line treatment of monomorphic VT.
Amiodarone – common in the US but per the AHA guidelines “reasonable in patients with sustained monomorphic VT that is hemodynamically unstable, refractory to conversion with countershock, or recurrent despite procainamide or other agents. (Level of Evidence: C)” .
Note: Dangerous if prolonged QT 
Lidocaine – “may be reasonable” 
Stable patients with polymorphic VT –
Beta-blockers (particularly if ischemic)
Cardiac catheterization if potentially ischemic cause 
Torsades de Pointes – withdraw offending agent, magnesium sulfate IV if “a few episodes” per the AHA
Question 1.A 26-year-old woman presents with dizziness and palpitations. She reports episodes of these symptoms beginning about 1 week ago, which initially only lasted a few minutes. However, for the past two days, she has had about 4 episodes a day which last about 20 minutes each. Her social history is significant for heavy caffeine intake. Her pulse is 166 bpm and her blood pressure is 140/70. Her rhythm strip is seen below.
Question 2. A 33-year-old woman with chronic persistent asthma presents with palpitations. Her vital signs are HR 210, BP 118/73, and pulse oxygenation of 97% on room air. An ECG is shown below.
The paper: The authors took blood samples from 760 healthy pregnant patients at one point during their pregnancy. They propose a continuous increase for a normal d-dimer cut off throughout gestation.
1-12 weeks: n=33, 81% with normal d-dimer
19-21 weeks: n=53, 32% with normal d-dimer
28-36 weeks: n=8, 6% with normal d-dimer
39-40 weeks: 0, 0% normal d-dimer
Postpartum day 2: n=12, 8% with normal d-dimer
Dr. Radecki’s “Take Home:“
Dr. Kline has advocated for the following d-dimer cut offs in pregnancy: 1st trimester 750 ng/mL, 2nd trimester 1000 ng/mL, and 3rd trimester 1250 ng/mL(based on a standard cut-off of 500 ng/mL) and this may be reasonable but is not rooted in robust evidence.
Interestingly, this post was followed by another post covering an article by Hutchinson et al from Am J Roentgenol showing that of 174 CTPAs initially read as positive, 45 were read as negative by chest radiologist upon blinded retrospective review. That means 25.9% of this cohort diagnosed with PE apparently had negative CT scans.
Core Content – Hemoptysis
Tintinalli (7e) Chapter 66; Rosen’s Emergency Medicine (8e) Chapter 24
Etiology: Most common causes are bronchitis (often blood tinged sputum), infection (abscess, pneumonia, tuberculosis), neoplasm (lung cancer). Other causes include iatrogenic causes (bronchoscopy, biopsy, aspirated foreign body), anticoagulation, and autoimmune diseases such as granulomatous polyangiitis (Wegener’s), lupus, and Goodpasture’s.
Question 1. A 50-year-old man, nonsmoker, presents to the ED with a 2-day history of cough now associated with frank hemoptysis. He denies any constitutional symptoms. Vital signs are BP 125/70, HR 80, RR 16, and pulse oximetry is 98% on room air. On exam, his lung fields are clear; the remainder of the exam is unremarkable. A chest radiograph is performed, which is normal.
Question 2. A 55-year-old man, smoker, presents to the ED with hemoptysis and dyspnea for 4 weeks. His VS are T 37°C, BP 146/76 mm Hg, HR 85 bpm, RR 20 per minute, and oxygen saturation 96% on RA. His lung exam reveals distant breath sounds on the left side. His chest X-ray is shown below.
1.C. The patient is hemodynamically stable with a normal chest radiograph, so he does not require ICU admission (A). Patients with massive hemoptysis require ICU admission. The decision to perform a bronchoscopy (B) in this patient will be left up to the pulmonologist. Given the overall clinical picture, urgent bronchoscopy is not required in this case. With massive hemoptysis, an emergent bronchoscopy is indicated. Bronchitis (D) typically presents with the abrupt onset of cough with blood-streaked purulent sputum. The patient in the clinical scenario has persistent frank hemoptysis, which mandates further investigation. In a patient who does not smoke, is under the age of 40, and has a normal chest radiograph and scant hemoptysis, treatment for bronchitis can be initiated with outpatient follow-up.
2. B. Although bronchitis (A) is the most common cause of hemoptysis (responsible for 15%-30% of cases), patients present with cough as the dominant symptom and have abnormal lung exams and normal chest x-rays. The cough may be productive of sputum. The diagnosis of pneumonia (C) requires focal findings on physical exam or infiltrates on radiographic imaging and is typically accompanied by a fever. Patients with lung cancer are at increased risk for pulmonary embolism (D). This patient’s Wells score is 2 (one point each for hemoptysis and malignancy), which makes the likelihood of PE 16% in an ED population. Given the lung mass seen on chest x-ray, lung cancer is more likely than PE.
530 patients with CT confirmed acute, uncomplicated appendicitis were randomized to operative intervention (n=273 receiving open laparotomies) or non-operative intervention (n=257 receiving antibiotics).
27.3% (n=70, CI 22-33.2%) of patients who received medical management (ertapenem x 3 days then 5 days of levofloxacin) had an appendectomy by the 1 year mark
7 patients (2.7%) in medical management group had complicated appendicitis at one year, 0 had abscesses
45 patients (20.5%) in the operative group had surgical complications
This is a non-inferiority study where the intent is to demonstrate that an experimental treatment (antibiotics alone) is not substantially worse than a control treatment (immediate surgery). The authors set the non-inferiority margin at 24%, which means that a failure rate (appendectomy by 1 year) >24% would render medical management inferior.
Authors Conclusion: “Among patients with CT-proven, uncomplicated appendicitis, antibiotic treatment did not meet the prespecified criterion for noninferiority compared with appendectomy.”
Spiegel’s Conclusion: “there is a great deal to be determined before this non-invasive strategy can be considered mainstream practice…in what was once considered an exclusively surgical disease, the majority of patients can effectively be managed conservatively. Despite not meeting their own high standards for non-inferiority, the authors demonstrated that for most patients with acute appendicitis, when treated conservatively with antibiotics we can avoid surgical intervention without complications of delays to definitive care.”
More FOAM on non-operative treatment of appendicitis: The SGEM
Use of contrast enhanced CT scans controversial. Rosenalli and the American College of radiology concur that oral contrast is probably not needed but does increase the emergency department length of stay [3-5].
Broad spectrum beta-lactams: ampicillin-sulbactam 3g IV (75 mg/kg IV in peds) piperacillin-tazobactam 4.5g IV, cefoxitin 2g IV (40 mg/kg IV in peds) OR metronidazole 500 mg IV + ciprofloxacin 400 mg IV
Other things to consider in special populations in right lower quadrant:
1. A 22-year-old man presents with abdominal pain followed by vomiting for 1 day. His examination is significant for right lower quadrant tenderness to palpation. He has a negative Rovsing sign.
2. A 22-year-old woman presents with lower abdominal pain and vaginal discharge. She is sexually active with men with inconsistent barrier protection. Her vitals are normal other than temperature of 101°F. On examination, there is yellow cervical discharge, no cervical motion tenderness, but uterine and left adnexal tenderness. An ultrasound does not show any evidence of tubo-ovarian abscess.
1. B. Sensitivity or the true positive rate measures the proportion of actual positives that are correctly identified as such. It is determined by dividing the number of true positives of the test by the number of true positives + false negatives. Tests with a high sensitivity are good for ruling out disease as the test has very few false negatives. A test with high sensitivity is advantageous as a screening tool as it misses very few people with the disease. The onset of pain before vomiting has been found to be as high as 100% sensitive in diagnosing acute appendicitis.Rovsing’s sign (D) (indirect tenderness) describes pain felt in the right lower quadrant upon palpation of the left lower quadrant. This sign signifies the presence of peritoneal irritation and has a sensitivity of 58%. Right lower quadrant pain (C) has a sensitivity of 81% and fever (A) has a sensitivity of 67%.
2.This patient presents with signs and symptoms consistent with pelvic inflammatory disease (PID) and should be treated with ceftriaxone 250 mg IM and 2 weeks of doxycycline. PID is an ascending infection beginning in the cervix and vagina and ascending to the upper genital tract. Neisseria gonorrhoeae and Chlamydia trachomatis are most commonly implicated. It can present with a myriad of symptoms although lower abdominal pain is the most common. Other symptoms include fever, cervical or vaginal discharge and dyspareunia. Pelvic examination reveals cervical motion tenderness (CMT), adnexal tenderness and vaginal or cervical discharge. Inadequately treated PID can lead to tubo-ovarian abscess, chronic dyspareunia and infertility. Due to the variable presentation and serious sequelae, the CDC recommends empiric treatment of all sexually active women who present with pelvic or abdominal pain and have any one of the following: 1) CMT, 2) adnexal tenderness or 3) uterine tenderness. Treatment should cover the most common organisms and typically consists of a third generation cephalosporin (ceftriaxone) and a prolonged course of doxycycline. Patients with systemic manifestations or difficulty tolerating PO should be admitted for management.Ceftriaxone and azithromycin (A) are used in the treatment of cervicitis or urethritis. Clindamycin (C) and metronidazole (D) are used in the treatment of bacterial vaginosis. References:
1.Salminen P, Paajanen H, Rautio T, et al. Antibiotic Therapy vs Appendectomy for Treatment of Uncomplicated Acute Appendicitis: The APPAC Randomized Clinical Trial. JAMA. 2015;313(23):2340
This week we cover posts from the Wessex ICS site, The Bottom Line, which is an excellent source for breakdown of recent and important trials. This site is great for reviews of high impact trials in critical care. We cover their post on a systematic review of peripheral pressor complications and then we delve into a recent prospective trial by Cardenas-Garcia and colleagues that came up at SMACC.
Systematic review of the literature 1946-Jan 2014 (does not include most recent trial)
Outcome – local tissue injury or extravasation: 325 separate events, 318/325 peripheral pressors
Signal that distal lines are not ideal for running pressors: 204 events (local tissue injury) were distal to the antecubital fossa/popliteal fossa (90% of events)
Signal that duration of pressors running peripherally may impact likelihood of adverse event. Increasing number of events were reported at the 6-12 hour mark (n=9) then 12-24 hour (n=18) and then almost all >24 hour
ICU fellows and attendings determined if peripheral pressors were warranted and then initiated the following protocol:
Vein diameter >4 mm measured with ultrasonography and PIV confirmed with US before pressors started
Upper extremity only, contralateral to the blood pressure cuff
IV size 20 gauge or 18 gauge
No hand, wrist, or antecubital fossa PIV access position
Blood return from the PIV access prior to VM administration
Assessment of PIV access function q 2h as per nursing protocol
Immediate alert by nursing staff to the medical team if line extravasation, with prompt initiation of local treatment
72 hours maximum duration of PIV access use
19/783 peripheral vasopressor administrations with infiltration of site (2%) with no events of local tissue injury
The take home: If a patient needs vasopressors, you can start them through a good, proximal peripheral IV. Sometimes patient or situation factors delay central lines, this doesn’t mean it needs to delay patient’s therapy. Know what to do in the event of infiltration (see this EMCrit post).
Tintinalli (7e) Chapter 24
Panchal et al – Phenylephrine bolus dosing in peri-intubation period
Answer. C. Norepinephrine is considered the vasopressor of choice for treatment of septic shock. Norepinephrine acts primarily as an α-adrenergic agonist, causing vasoconstriction that results in an increase in blood pressure. It also has β-adrenergic properties, which causes an increase in cardiac output and heart rate. The combination of α-adrenergic and β-adrenergic properties benefits patients who have septic shock. Norepinephrine also has a short duration of action, which allows for rapid adjustment of dosing in response to changes in a patient’s hemodynamic status. Dopamine (A) was once widely used in the treatment of septic shock, but studies have shown that it has no advantage over norepinephrine and its use is associated with a higher death rate. Epinephrine (B) has both α-adrenergic and β-adrenergic properties and has a greater affinity for alpha- and beta-receptors than norepinephrine. Its use is associated with a higher rate of cardiac dysrhythmias and a decrease in splanchnic blood flow. Phenylephrine (D) is a pure α-adrenergic agent that causes vasoconstriction and impairment of tissue blood flow throughout the body, most notably in the splanchnic circulation.
In a prior FOAMcastini, we covered the updated ACEP tPA clinical policy. As residents, we sought perspectives from experts, the FOAMcast brain trust (Drs. Anand Swaminathan, Ken Milne, Ryan Radecki, and David Newman). We (Jeremy) also interviewed Dr. Jerry Hoffman, faculty at UCLA.
In this interview, Dr. Jerry Hoffman, a public skeptic and author of peer reviewed critiques of tPA provides interesting perspective on more than thrombolysis but on the future of guidelines (referencing this paper) and science in Emergency Medicine.