Episode 37 – Lacerations

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The Free Open Access Medical Education (FOAM)

We cover a trick of the trade from Dr. Brian Lin, posted on the Academic Life in Emergency Medicine (ALiEM site) on hemostasis in finger tip avulsions. Dr. Lin also has his own excellent FOAM site on all things laceration – LacerationRepair.com.

We also cover FOAM on dogma of wound care from Dr. Ken Milne’s The Skeptic’s Guide to Emergency Medicine, Episode #63

Core Content – Wounds and Laceration Care

Tintinalli (7e) Chapter 44, “Wound Preparation.” Rosen’s  (8e) Chapter 59, “Wound Management Principles.”

Laceration Care:

  • Use gloves, they don’t have to be sterile [1].
  • Anesthetize (lidocaine with epinephrine is just fine).
  • Irrigate copiously. It’s estimated that one needs ~60 mL/centimeter of wound or at least 200 mL.
    • You can irrigate with water or saline. Potable tap water is fine [2,3]
  • For a cornucopia of laceration techniques visit LacerationRepair.com
  • No clear “golden period” for laceration repair [4-6]. Rosen’s and Tintinalli recommend using clinical judgment as a guide.

Risks for Infection:

  • Diabetes
  • Length of laceration (>5 cm)
  • Location of the wound
  • Degree of contamination [6]

Age of wound when approximated (i.e. “golden period”) has not been found to be an independent risk factor). Rosen’s sites use of epinephrine as a risk but only cites a paper by Barker et al from 1982 in which tetracaine/epinephrine/cocaine was applied to wounds inflicted by researchers that were inoculated by s. aureus.

Prophylactic antibiotics:

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Generously Donated Rosh Review Questions 

Question 1.  An 18-year-old woman presents with a laceration to her face from a dog bite that occurred 24 hours ago. The patient owns the dog. Examination reveals a 4 cm laceration to the left cheek with no signs of infection. [polldaddy poll=9180209]

Question 2A 30-year-old man presents with a 2 cm linear laceration through his right eyebrow that he sustained after hitting his head on the kitchen cabinet. You determine that the wound will require repair with sutures. [polldaddy poll=9180210]

Answers

  1. Mammal bites to any part of the body should be copiously irrigated and explored followed by an assessment for primary closure. In this patient, primary closure is recommended as the laceration is on the face. Canine bites often involve laceration as well as crush injury to tissue depending on the size of dog. The presence of a crush injury may make primary wound repair difficult. Additionally, devascularization of the tissue may make primary closure contraindicated as the risk of infection increases. Classically, it was taught that lacerations sustained from dog bites should be irrigated, given antibiotics and not primarily repaired because of these risks. However, more recent literature has shown that the risk of infection was no different for primary closure versus healing by secondary intention. Additionally, if the laceration is to a cosmetic area like the face, primary repair should be attempted. As with any laceration, tetanus status should be updated. Copious irrigation and wound exploration is central to good wound care. Exploration should pay particular attention to the presence of foreign bodies especially teeth, which may break off during the bite. Antibiotics (A & C) are not routinely needed for dog bites despite classic teaching. Antibiotics should be reserved for patients with signs of infection, multiple comorbidities or large wounds with gross contamination. If antibiotics are given, they should primarily cover Staphylococcus and Streptococcus species, as these are the predominant organisms in the canine oral cavity. Eikenella and Pasturella are less commonly responsible for infections. Irrigation and antibiotics alone (A) would be indicated for dog bites that are grossly infected or have large defects that cannot be primarily closed. Wound closure and antibiotics without irrigation (D) is also contraindicated as copious irrigation is central to proper wound management.
  2. A pair of clean, non-sterile gloves can be worn by the physician (and any assistants) during laceration repair. The use of sterile gloves has not been proven to be associated with lower infection rates and is not required. Wounds must be prepped prior to closure. This generally involves cleaning and draping the wound, providing local or regional anesthesia, copious irrigation and exploring the wound to evaluate the integrity underlying structures and identify any foreign bodies. The skin surrounding a wound should be cleansed with either 10% povidone-iodine (C) or chlorhexidine gluconate solution. In general, these commercially available antiseptics should not be used for wound irrigation, as they can be toxic to the tissues. Irrigation should then follow with copious amounts of tap water or saline (at least 250 mL). This is best achieved with a large volume syringe attached to an 18-gauge needle or another commercially available irrigation device that achieves adequate pressure for irrigation. Alternatively, patients can irrigate at the sink if the laceration is in area that allows for this. Shaving of hair been shown to increase the risk of infection and should generally be avoided. It is best to apply a small amount of petroleum- or water-based lubricant to the hair to keep it out of the wound. Alternatively, hair can be clipped with scissors when necessary. Eyebrows (B) in particular should not be shaved as they provide anatomic landmarks that aid in wound approximation and removal results in poor short- and long-term cosmetic effect. In general, non-complex facial wounds are closed with nonabsorbable suture material, such as nylon or polypropylene. Most commonly this will be done with 6-0 suture, as it provides the best cosmetic effect. The use of 3-0 (D) and 4-0 suture is reserved for repair of fascia or wounds that are under high stress, such as those that overly major joints or involve the scalp.

References:

  1. Perelman VS, Francis GJ, Rutledge T, et al. Sterile versus nonsterile gloves for repair of uncomplicated lacerations in the emergency department: a randomized controlled trial. Annals of emergency medicine. 43(3):362-70. 2004
  2. Fernandez R, Griffiths R. Water for wound cleansing. The Cochrane database of systematic reviews. 2:CD003861. 2012.
  3. Weiss EA, Oldham G, Lin M, Foster T, Quinn JV. Water is a safe and effective alternative to sterile normal saline for wound irrigation prior to suturing: a prospective, double-blind, randomised, controlled clinical trial. BMJ open. 3(1):. 2013.
  4. American College of Emergency Physicians: Clinical policy for the initial approach to patients presenting with penetrating extremity trauma. Annals of emergency medicine. 33(5):612-36. 1999. [pubmed] **A past policy, no current clinical policy
  5. Zehtabchi S, Tan A, Yadav K, Badawy A, Lucchesi M. The impact of wound age on the infection rate of simple lacerations repaired in the emergency department. Injury. 43(11):1793-8. 2012.
  6. Quinn JV, Polevoi SK, Kohn MA. Traumatic lacerations: what are the risks for infection and has the ‘golden period’ of laceration care disappeared? Emergency medicine journal : EMJ. 31(2):96-100. 2014.
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Episode 36 – Rib and Sternal Fractures

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The Free Open Access Medical Education (FOAM)

This week we cover a joint piece between the Ultrasound Podcast and SonoIn5 on diagnosis of rib and sternal fractures with ultrasound.

Technique:  Linear probe, in line with the long axis of the bone (vertical for sternum, horizontal-ish for ribs).

Diagnosis: Cortical disruption (step off). Excellent sensitivity for sternal fractures [1-3]

Sternal Fracture
Sternal Fracture
  • Caution with sternal fractures as the sternomanubrial joint can mimic fracture, but looks more “bumpy” (see below)

Core Content – Rib and Sternal Fractures

Tintinalli (7e) Chapters 258, 259; Rosen (8e) Chapter 45 

Rib Fractures

Diagnosis:

  • Chest x-ray initial test of choice – may miss 50% of fractures, unclear if this is clinically significant [6]
  • Ultrasound has found to have excellent sensitivity [7]
  • Rib films are NOT recommended [4-6].

Complications: Traumatic rib fractures may be associated with other traumatic injuries such as pneumothorax, hemothorax, or in the case of lower rib fractures, intra-abdominal injury. However, rib fractures themselves have been associated with mortality, most often as sequelae of pulmonary embarrassment including pneumonia, intubation, and death. Mortality in elderly patients with rib fractures is significantly higher than the younger counterparts at 22% and 10% respectively [8,9].

  • Mortality is between 3-13%
  • Risk stratification (see this post): Battle and colleagues developed a prognostic scoring system, not externally validated and unclear if it would change practice, that highlights common sense predictors of poorer outcomes:
    • Age (>65)
    • Higher number of rib fractures
    • Chronic lung disease
    • Hypoxia (<90%)
    • Pre-injury anticoagulant use [11]

Treatment

  • Analgesia:
    • Often includes NSAIDS (ibuprofen), acetaminophen, and narcotics +/- gabapentin (ibuprofen and gabapentin depending on renal function)
    • Epidural analgesia – highly recommended in the EAST guidelines [14].
    • Paracostal analgesia (ex: ON-Q pump) – not sufficient evidence for EAST recommendation (2005) [14]
  • Pulmonary Hygiene (formerly pulmonary toilet):  involved incentive spirometry, coughing, mobilization (up, out of bed), and possibly chest physical therapy
  • ORIF, “rib fixation” or “rib plating,” is increasingly common in the US and studies have found improvements in ICU LOS and ventilator days [15]

Disposition

  • Many rib fracture patients will need to be admitted to the hospital for pain control, observation, and pulmonary hygiene.
    • Some rib fracture patients may benefit from care at trauma centers.  Lee et al  wrote that 3+ rib fractures exists as an indication for transfer to a level 1 trauma center and many places ascribe to this, it depends on the hospital and physicians.
    • While patients in the ED may look good, patients may benefit from high intensity floors (ie stepdown units) and many patients get observed in ICUs, again, depending on local practice patterns. Some protocols risk stratify patients (i.e. to the ICU vs floor) by incentive spirometry.
  • Patients with adequate pain control who are low risk (younger, <3 rib fractures, good effort on incentive spirometry) may be discharged from the ED with analgesia and education on importance of pulmonary hygiene

Sternal Fractures – more common with ubiquity of airbags and seatbelts.

Diagnosis:  Classically the “gold standard” has been lateral x-ray. However, CT technology has improved since those studies. Ample literature suggests that ultrasound has excellent sensitivity [1-3].

Complications: Historically, sternal fractures were associated with injuries of the great vessels, high mortality, and blunt cardiac injury (BCI) [16-18].  The most recent iteration of the EAST guidelines states, “the presence of a sternal fracture alone does not predict the presence of BCI and thus should not prompt monitoring in the setting of normal ECG result and troponin I level” (Level 2) [18].

Treatment: Analgesia. Most patients with isolated sternal fractures (no pneumothorax, hemothorax, BCI, or hemodynamic instability) that have adequate pain control can be discharged from the ED [1-2].

Blunt Cardiac Injury

A broad category including a range of injuries from clinically silent dysrhythmias to cardiac wall rupture or vasospasm. BCI often results from high impact injury and should be considered in patients with significant thoracic trauma including rib fractures, sternal fracture, pneumothorax, hemothorax, and pulmonary contusion.

Diagnosis: There is no gold standard test.  One can rule out BCI with a normal ECG and a single normal troponin I [18].

Management: If an ECG or troponin is abnormal, admit to telemetry for monitoring and echo.

Generously Donated Rosh Review Questions 

Question 1.  A 23-year-old man presents with chest pain after a motor vehicle collision. The patient’s chest struck the steering wheel. He has no other complaints or injuries. Chest X-ray is unremarkable. ECG shows sinus tachycardia with anterior ST depressions. A troponin is sent and is positive at 3.50 mg/dl. [polldaddy poll=9134639]

Question 2A 20-year-old man presents with left rib pain after falling while playing soccer and striking his chest. Vital signs are normal. On physical examination, the patient has tenderness to palpation over the 4th rib in the midaxillary line. [polldaddy poll=9134640]

Question 3.  A 32-year-old woman was the restrained driver involved in a head-on motor vehicle collision (MVC) 2 days prior to presentation. She is complaining of chest pain and bruising to her chest. Her blood pressure is 118/78 mm Hg, pulse is 88 beats/minute, respirations are 18 breaths/minute and oxygen saturation is 96% on room air. You note bony tenderness and ecchymosis to her sternum. You order a chest X-ray and diagnose a non-displaced sternal fracture. [polldaddy poll=9134643]

Answers

  1. This patient presents with a myocardial contusion and should have an echocardiogram performed to look for any cardiac damage. Myocardial contusion describes a nebulous condition. It can occur through several mechanisms including a direct blow to the chest and compressive force over a prolonged period of time. Histologically, the disorder has similar findings to those seen after acute myocardial infarction. The majority of contusions heal spontaneously but small pericardial effusions may develop. Delayed rupture after resorption of hematoma is feared but rare complication. Patients with myocardial contusion will present after trauma with external signs of trauma and typically have other concomitant thoracic lesions (pulmonary contusion, pneumothorax, hemothorax). Patients will typically have tachycardia (up to 70%). ECG may show dysrrhythmia or ST changes but may also be normal. Although it is not effective to admit all patients for workup for myocardial contusion and the disease has a very low rate of cardiac complications, in the presence of ECG changes and elevated biomarkers, observation and echocardiography are a reasonable approach. Echocardiogram can be used to diagnose pericardial effusion, thrombi formation and valvular disruption.Cardiac catheterization (A) is not necessary after a myocardial contusion as coronary artery obstruction is not part of the pathophsyiology. The patient should not be discharged home (B)without an echocardiogram. Pericardiocentesis (D) is only necessary in the presence of a large pericardial effusion or one causing cardiac tamponade.
  2. This patient presents with signs and symptoms consistent with a rib facture. A chest X-ray should be performed to rule out any other pathology including pneumothorax and pulmonary contusion. Rib fractures are a common injury after thoracic trauma and the incidence increases with increasing age. They may be associated with a number of potential complications including pulmonary contusions, hemothorax, penumothorax and post-traumatic pneumonia. Fractures are most common at the posterior angle, which represents the weakest area. The ribs most commonly fractured are the 4th – 9th ribs. The 9th – 11th ribs are mobile, which reduces the risk of fracture. However, fractures of these ribs are more likely to be associated with intraabdominal injuries. Rib fractures should be suspected based on history and clinical evaluation. Patients will present with chest pain and tenderness over the area. Imaging should be obtained to rule out the more serious associated complications of pneumothorax, hemothorax and pulmonary contusion. Chest X-ray is the appropriate modality for this but often will not demonstrate the presence of a single rib fracture when it is in fact present. This is particularly true of non-displaced fractures. Rib belts (B) are discouraged as they may decrease the depth of respiration and lead to atelectasis and pneumonia. CT scan of the chest (D) is not routinely required for management of a simple rib fracture. Analgesia and discharge home (A) is likley to occur once more serious pathology is ruled out with a chest X-ray. Patients with rib fractures should also receive an incentive spirometer to help reduce the complication of pneumonia.
  3. Isolated, non-displaced sternal fractures are associated with low overall mortality rates. Fractures and dislocations of the sternum are caused primarily by anterior blunt chest wall trauma during a head-on MVC. Isolated fractures of the sternum most commonly occur when the chest wall is thrust against a diagonal seatbelt strap during rapid deceleration in a frontal impact MVC. They are more common in older individuals and women. Most fractures are transverse and non-displaced and can be diagnosed on a lateral chest radiograph. Although a fracture of the sternum can be seen following major thoracic trauma, its presence alone does not indicate severe underlying thoracic injury. However, if other significant underlying thoracic injuries are suspected, a CT-scan of the thorax should be performed

References:

  1. You JS, Chung YE, Kim D, Park S, Chung SP. Role of sonography in the emergency room to diagnose sternal fractures. Journal of clinical ultrasound : JCU. 38(3):135-7. 2010. [pubmed]
  2. Engin G, Yekeler E, Güloğlu R, Acunaş B, Acunaş G. US versus conventional radiography in the diagnosis of sternal fractures. Acta radiologica (Stockholm, Sweden : 1987). 41(3):296-9. 2000. [pubmed]
  3. Jin W, Yang DM, Kim HC, Ryu KN. Diagnostic values of sonography for assessment of sternal fractures compared with conventional radiography and bone scans. J Ultrasound Med. 2006 Oct. 25(10):1263-8; quiz 1269-70.
  4. ”Pulmonary Trauma” Tintinalli’s Emergency Medicine: A Comprehensive Study Guide.  7th ed. Ch 258.
  5.  “Thoracic Trauma” Rosen’s Emergency Medicine. 8th ed. Chapter 45.
  6. Henry TS, Kirsch J. ACR Appropriateness Criteria® rib fractures. Journal of thoracic imaging. 29(6):364-6. 2014. [pubmed]
  7. Chan SS. Emergency bedside ultrasound for the diagnosis of rib fractures. The American journal of emergency medicine. 27(5):617-20. 2009. [pubmed]
  8.  Ziegler DW, Agarwal NN. The morbidity and mortality of rib fractures. J. Trauma. 1994;37(6):975–9.
  9. Bulger EM, Arneson M a, Mock CN, Jurkovich GJ. Rib fractures in the elderly. J. Trauma. 2000;48(6):1040–6
  10. Flagel BT, Luchette F a, Reed RL, et al. Half-a-dozen ribs: the breakpoint for mortality. Surgery. 2005;138(4):717–23; discussion 723–5.
  11. Battle CE, Hutchings H, Evans P. Risk factors that predict mortality in patients with blunt chest wall trauma: a systematic review and meta-analysis. Injury. 2012;43(1):8–17.
  12. Livingston DH, Shogan B, John P, Lavery RF. CT diagnosis of Rib fractures and the prediction of acute respiratory failure. The Journal of trauma. 64(4):905-11. 2008. [pubmed]
  13. Battle CE, Hutchings H, Lovett S.  Predicting outcomes after blunt chest wall trauma: development and external validation of a new prognostic model Critical Care 2014, 18:R98
  14. Pain Management in Blunt Thoracic Trauma (BTT)J Trauma. 59(5):1256-1267, November 2005.
  15. Doben AR, Eriksson EA, Denlinger CE. Surgical rib fixation for flail chest deformity improves liberation from mechanical ventilation. Journal of critical care. 29(1):139-43. 2014. [pubmed]
  16. Screening for Blunt Cardiac Injury. J Trauma. 73(5):S301-S306, November 2012
  17. Karangelis D, Koufakis T, Spiliopoulos K, Tsilimingas N, Bouliaris K, Desimonas N. Management of isolated sternal fractures using a practical algorithm. J Emerg Trauma Shock. 7(3):170-. 2014. [article]
  18. Dua A, McMaster J, Desai PJ et al. The Association between Blunt Cardiac Injury and Isolated Sternal Fracture. Cardiology Research and Practice. 2014:1-3. 2014. [article]

FOAMcastini – Core Content Journal Club

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This is an exciting week of primary literature, particularly as many large critical care trials were published in major journals despite being “negative studies.”  We are excited by this as, too often, we see “negative studies” discarded.  Further, these studies examined things some practices we seem to believe in: balanced crystalloids, apneic oxygenation (see Dr. Scott Weingart’s podcast on the FELLOW study), treating fever. We love that the Free Open Access Medical Education (FOAM) community and study authors are examining beloved practice and open to questioning the very things we believe in. Well done.

We cover two core content papers out by Dr. Paul Young (@dogICUma) in JAMA and NEJM this week. His trials are as clever as his Twitter handle.

SPLIT – The FOAM world has sung the praises of balanced fluids given they have more physiologic composition. The thought, as detailed in this post, is that 0.9% NaCl contains an ABnormally large amount of chloride which may cause a hyperchloremic metabolic acidosis. Prior literature suggests an increased incidence of kidney injury with saline compared with balanced solutions. Thus, Dr. Paul Young and colleagues sought to study this with the best trial, to date, on this topic.

  • Multicenter, blinded,  cluster-randomized, double-crossover trial of adult ICU patients receiving crystalloids randomizing patients to 0.9%NaCl or Plasma-lyte (balanced solution).
    • Sites used one fluid for seven weeks and then crossed over to the other fluid (labeled Fluids A and B).
  • Primary outcome: AKI according to the RIFLE criteria  within 90 days – no difference between groups.
    • 9.6% in Plasma-lyte group vs 9.2% in the saline group (absolute difference 0.4% [95% CI, −2.1%-2.9%]; RR, 1.04 [95% CI, 0.80-1.36]; P = .77)
  • Secondary outcomes: No difference in renal replacement therapy, ICU days, mechanical ventilation, or mortality
  • A few things to keep in mind:
    • 70% of patients were admitted to the ICU from the OR (mostly cardiac surgery) and only ~15% from the ED
    • Patients got a median of 2L (1L -3.5L) of the study fluid, that’s it. These were not large volume resuscitations.
    • 90% of patients received fluids prior to enrollment, 60% got balanced crystalloid and only 30% 0.9% NaCl.

HEAT – We can’t help treating fever. We like the numbers euboxic, elevated temp? It must be bad! Doctors, parents, nurses treat fever reflexively.  Yet, there’s a thought that fever may be evolutionary and could potentially be protective. Treating pain or discomfort? That’s one thing, but here the authors sought to determine if there was a clinically important benefit to treating the number in ICU patients.

  • Randomised controlled, double blinded study of n=690 ICU patients with T>38F + suspected infection randomized to receive either 1 g paracetamol (acetaminophen/APAP) or placebo every 6 hours.
  • Primary outcome: median ICU-free days to day 28 – no difference 23 (IQR 13-25) in paracetamol group vs 22 in placebo group (IQR 12-25); P=0.07
  • No difference in secondary outcomes of mortality at 28 and 90 days
  • Limitations: ~30% of patients in both arms received open label APAP after the course of the study drug

Bottom Line Pearls:

  • It appears we may be SPLITting hairs over fluid choices. Giving a couple of liters? Fluid choice may not matter. SPLIT does not provide literature for larger volume resuscitations.
  • Treating fever in ICU patients with suspected infection doesn’t have an effect on ICU free days. Treat discomfort and pain with APAP but don’t expect to save lives or ICU beds by doing so.
  • “Negative studies” are important. So is examining our practice.
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FOAMcastini – The “Left Shift”

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The Free Open Access Medical Education (FOAM)

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.

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Episode 34 – Tachyarrhythmias

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The Free Open Access Medical Education (FOAM)

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

SVT 

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.

Diagnosis: JACC algorithm

Treatment:

  • Unstable patients – electrical cardioversion at 0.5-1 J/kg (100J for an adult) + ABCs!
  • Stable patients-
    • 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% [3].
    • 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].

VT

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]

Treatment:

  • Unstable patients – electrical cardioversion at 0.5-1 J/kg (100J for an adult) + ABCs!
  • Stable patients with monomorphic VT
    • Electrical cardioversion
    • Procainamide – Level B recommendation for first line treatment of monomorphic VT[6].
    • 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)” [6].
      • Note: Dangerous if prolonged QT [6]
    • Lidocaine – “may be reasonable” [6]
  • Stable patients with polymorphic VT
    • Electrical cardioversion
    • Beta-blockers (particularly if ischemic)
    • Amiodarone
    • Cardiac catheterization if potentially ischemic cause [6]
  • Torsades de Pointes – withdraw offending agent, magnesium sulfate IV if “a few episodes” per the AHA

Generously Donated Rosh Review Questions 

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. [polldaddy poll=9061960]

Screen Shot 2015-09-05 at 9.52.22 AM

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. [polldaddy poll=9061966]

Screen Shot 2015-09-05 at 9.53.15 AM

References:

  1. Whinnett ZI, Sohaib SM, Davies DW. Diagnosis and management of supraventricular tachycardia. BMJ (Clinical research ed.). 345:e7769. 2012
  2. Link MS. Clinical practice. Evaluation and initial treatment of supraventricular tachycardia. The New England journal of medicine. 367(15):1438-48. 2012.
  3. Smith et al. Effectiveness of the Valsalva Manoeuvre for reversion of supraventricular tachycardia. Cochrane Database Syst Rev. 2013 Mar 28;3:CD009502. doi: 10.1002/14651858.CD009502.pub2
  4. ”Cardiac Rhythm Disturbances.” Tintinalli’s Emergency Medicine: A Comprehensive Study Guide.  7th ed. pp 136-146.
  5. “Tachyarrhythmias.” Rosen’s Emergency Medicine. 8th ed. Chapter 79.
  6. Zipes DP, Camm AJ, Borggrefe M et al. ACC/AHA/ESC 2006 Guidelines for Management of Patients With Ventricular Arrhythmias and the Prevention of Sudden Cardiac Death. Journal of the American College of Cardiology. 48(5):e247-e346. 2006
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Episode 33 – Hemoptysis

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The Free Open Access Medical Education (FOAM)

Dr. Ryan Radecki of Emergency Medicine Literature of Note reviews Gestational Age D-Dimers covering an article by Murphy and colleagues in BJOG.  

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.

Workup:

Hemoptysis Workup

Generously Donated Rosh Review Questions 

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. [polldaddy poll=9039260]

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. [polldaddy poll=9039262]

Rosh Review
Rosh Review

Answers

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.

References:

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Episode 31 – Vasopressors

(ITUNES OR Listen Here)

The Free Open Access Medical Education (FOAM)

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.

The Bottom Line on the Loubani paper

  • 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

The Cardenas-Garcia Paper

  • Single arm consecutive study of ICU patients
  • 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
  • N=734 patients
  • 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).

Core Content
Tintinalli (7e) Chapter 24

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Panchal et al – Phenylephrine bolus dosing in peri-intubation period

Central line technique from Dr. Reuben Strayer – Wire through catheter vs wire through needle

Generously Donated Rosh Review Questions 

1.[polldaddy poll=8996471]

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.

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FOAMcastini – ACEP tPA Clinical Policy

(iTunes or Listen Here)

In a prior FOAMcastini, we covered a draft of an ACEP clinical policy on tPA for acute ischemic stroke.  This came in the wake of years of controversy over the aggressive position taken in the 2012 clinical policy.  In June ACEP released the final version of this policy.

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Per the policy within 3 hours:

  • NNT of 8 for excellent functional outcomes; 95% [CI] 4-31
    • Paucity of patients presenting with mild stroke (NIHSS score 0 to 4)
  • NNH of 17 for symptomatic intracerebral hemorrhage; 95% CI 12-34

While FOAMcast is not an interview style podcast, we felt compelled to get some perspective on Emergency Physicians a little more experienced than ourselves.  Here we interview:

Dr. Ryan Radecki (@emlitofnote), Assistant Professor, University of Texas – Houston

  • See his response to the policy on his blog here

Dr. David Newman (#draftnewman), Associate Professor of Emergency Medicine, Mount Sinai Hospital

Dr. Anand Swaminathan (@EMSwami), Assistant Professor of Emergency Medicine, NYU

Dr. Ken Milne (@thesgem), Chief of Staff at South Huron Hospital

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FOAMcastini – SMACC Day 3

(ITUNES OR Listen Here)

We are bringing you pearls from conferences we attend including SMACC (#smaccUS).  This conference was amazing and we enjoyed meeting everyone.  We look forward to seeing y’all at SMACC in Dublin June 13-16, 2016 and hope you check out the Free Open Access Medical education (FOAM) lectures from SMACC, in podcast form, until then.

Things in medicine aren’t always engineered to help us succeed. Engineering the environment smarter may make care safer. – Kevin Fong

  • Medication vials often look quite similar and in a busy, heated moment this may lead to medication errors.  Check out the EZdrugID project.
EZdrugID
Photo: Dr. Nicholas Chrimes

Analgesia, there’s more to it than medicine – Jeremy Faust

  • Distraction is a good thing.  Doing a painful procedure such as injecting local anesthetic? Distract the patient in tactile fashion by lightly scratching the patient proximal to the procedure. Alternative, music and videos can distract children and adults.
  • Calm music may reduce perception of pain.
  • Take advantage of child life, if you have them [AHRQ]!

The Glasgow Coma Scale is a problem – Mark Wilson (see this blog post)

  • The score doesn’t have intrinsic meaning. A GCS score can be associated with mortality ranging from 20-57%, depending on the individual components [Healey]
  • We’re really bad at assigning correct GCS scores to patients, even when we have cheat sheets [Feldman]
  • The interrater reliability of the GCS is abysmal [Bledsoe, Gill]
  • Describe the patient’s exam!

Shift work is disruptive – Haney Mallemat

  • Microsleep is dangerous, yet fairly common in the over tired provider
  • Replacing traditional night shifts with “casino shifts” may help.  These are often comprised of 2 short shifts from 10p-4a and 4a-10a with the notion that each provider would get sleep during the “anchor period” of the Circadian cycle, 2am-6am.  Small studies have shown this feasible, preferred by many, and perhaps perceived [Croskerry, Dukelow]
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Episode 30 – Thyroid

(ITUNES OR Listen Here)

The Free Open Access Medical Education (FOAM)

This week we cover Dr. Scott Weingart’s EMCrit episode on Thyroid Storm

Diagnosis: Hyperthyroid, Fever, Altered Mental Status, Sympathetic Surge, Precipitating Event

Treatment (PPID – PTU, propranolol, iodine, dexamethasone or MIEH – methimazole, iodine, esmolol, hydrocortisone):

  • Supportive care – IV fluids, identify trigger (infection, DKA, trauma, etc)
  • Block production of thyroid hormone: Methimazole or Propothiouracil (PTU)
  • Block thyroid hormone release: Iodine (wait 60 min after giving methimazole or PTU)
  • Calm the sympathetic surge: beta-blockade (propranolol – also inhibits conversion of T4 to the more active T3, metoprolol or esmolol)
  • Block conversion of T4 to T3 and prevent adrenal insufficiency: steroids (dexamethasone, hydrocortisone)
From Rosh Review

Core Content
Rosen’s Emergency Medicine (8e) Chapter 128, Tintinalli (7e) Chapter 223

Thyroid disorders exist on a spectrum from myxedema coma to thyroid storm, with a large area in between.

Hyperthyroidism – too much thyroid hormones only from the thyroid gland

Thyrotoxicosis –  too much thyroid hormone from any cause (i.e. taking too much thyroid supplement)

Thyroid Storm – see above. Thyrotoxicosis with  increased adrenergic hyperactivity or abnormal response to the thyroid hormones by the peripheral tissues

Myxedema coma – These patients are the opposite of thyroid storm, all the systems are depressed (they are essentially hypo-everything).  The diagnosis is clinical but these patients will have significantly elevated TSH with low T3/T4.

  • Altered mental status
  • Hypothermic, <35.5°C (95.9°F)
  • Hypotensive
  • Bradycardic
  • Hyponatremic
  • Hypoglycemic

Treatment

  • Intravenous levothyroxine (T4) although endocrine may recommend that some patients get intravenous T3
  • Supportive care – passive rewarming, dextrose, intravenous fluids
  • Steroids
  • Identify underlying cause

Generously Donated Rosh Review Questions 

1. A 28-year-old woman with no past medical history presents to the emergency department with acute dyspnea. Physical exam reveals tachycardia, warm extremities, wide-pulse pressure, bounding pulses, a systolic flow murmur, exophthalmos and a neck mass. [polldaddy poll=8935230]

2. [polldaddy poll=8936552]

Answers

1. This patient most likely has high-output heart failure secondary to thyrotoxicosis. High output heart failure occurs when cardiac output is elevated in patients with reduced systemic vascular resistance. Examples include thyrotoxicosis, anemia, pregnancy, beriberi and Paget’s disease. Patients with high output heart failure usually have normal pump function, but it is not adequate to meet the high metabolic demands. In high output heart failure the heart rate is typically elevated, the pulse is usually bounding and the pulse pressure wide. Pistol-shot sounds may be auscultated over the femoral arteries, which is referred to as Traube’s sign. Subungual capillary pulsations, often referred to as Quincke’s pulse, may be also be present. Although these findings may be seen in other cardiac conditions, such as aortic regurgitation or patent ductus arteriosus, in the absence of those conditions, these signs are highly suggestive of elevated left ventricular stroke volume due to a hyperdynamic state. Patients with chronic high output also may develop signs and symptoms classically associated with the more common low-output heart failure; specifically, they may develop pulmonary or systemic venous congestion or both, while maintaining the above normal cardiac output.

Low output heart failure (C) is often secondary to ischemic heart disease, hypertension, dilated cardiomyopathy, valvular and pericardial disease or arrhythmia. It can cause dyspnea but is not associated with symptoms of a hyperdyanmic state. Aortic regurgitation (A) is classically associated with bounding pulses, a wide pulse pressure and subungual capillary pulsations; however, aortic regurgitation is less likely in a young woman with no past cardiac history. Additionally, this woman has exophthalmos and a goiter on exam, which support the diagnosis of thyrotoxicosis. Methamphetamine intoxication (D) usually presents with agitation, tachycardia, and psychosis; however, it is not associated with a hyperdynamic state, exophthalmos or a goiter.

2.  Hyperthyroidism is a condition in which there is overproduction and increased circulation of thyroid hormone. Hyperthyroidism has a variety of causes and variable presentation. Increased circulating thyroid hormone causes a hypermetabolic state and increases beta-adrenergic activity. Initially, patients may have vague constitutional symptoms. As the disease progresses, clinical manifestations may become more organ-specific. Thyrotoxicosis or thyroid storm represents the most severe manifestation of the disease. Thyroid storm is life threatening and characterized by hyperadrenergic activity. Patients present with vital sign abnormalities including tachypnea, tachycardia, hyperthermia and hypertension. ECG may show atrial dysrhythmias like atrial flutter and fibrillation or simple sinus tachycardia. High-output cardiac failure is common as well. Physical features include goiter, opthalmopathy and tremors. Patients will also have increased reflexes and altered mental status. Thyroid storm treatment involves suppression of thyroid hormone synthesis and secretion, prevention of peripheral conversion from T4 to T3 and blocking the peripheral adrenergic stimulation. Blocking the peripheral effects of thyroid hormone is best accomplished with a beta-blocker and propranolol is preferred as it also decreases conversion of T4 to T3.

Lithium (A) is a cause of hypothyroidism. In hyperthyroidism, TSH is depressed (C). Weight gain (D) is common in hypothyroidism.

Theme Music:  Flippen performed by The Punch Brothers, used with permission

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