Author Archives: David Lewis

Periorbital Inflammation – Red Eye – Red Flags

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Medical Student Clinical Pearl

Alysha Roberts

MD Candidate, Class of 2021

Dalhousie University

@aeroberts_21

Reviewed & Edited by Dr David Lewis (@e_med_doc)

All case histories are illustrative and not based on any individual.

Case

A 40 year old male presents to the emergency department with a red, swollen eye. Without a known trigger, he had a one day history of progressive pain, erythema, and edema surrounding his left eye. He denied any fever or chills or visual changes, or headache. A thorough review of systems was negative, except for a complaint of worsening pain with extraocular movement.

On exam, he was afebrile and his vital signs were within normal limits. His visual acuity was normal, and pupils were equal and reactive to light. Extraocular movements were intact but associated with worsening pain. The periorbital tissue was erythematous, edematous, and hot to touch. Examination is limited by the severity of the patient’s swelling. Figure 1 illustrates an example of a patient with severe, unilateral eyelid swelling and erythema.

You suspect periorbital cellulitis.

Figure 1. Unilateral eyelid edema. Retrieved from https://www.merckmanuals.com/professional/eye-disorders/orbital-diseases/preseptal-and-orbital-cellulitis

 

Periorbital Versus Orbital Cellulitis

Periorbital cellulitis, commonly referred to as pre-septal cellulitis, is an infection of the skin and soft tissue surrounding the orbit. Most commonly, it is the result of an infection spreading from the sinuses or from local trauma.1,2 It presents as a unilateral swelling of the eye-lid. Both periorbital and orbital cellulitis are most commonly caused by Staphylococcus Aureus and Streptococcus Pneumoniae. It is important to distinguish periorbital from orbital cellulitis, which is an infection of the orbit itself extending beyond the orbital septum. Orbital cellulitis is a sight-threatening emergency, and urgent imaging should be acquired in addition to consultation with ophthalmology or otolaryngology.3 Other complications of orbital cellulitis include orbital or subperiosteal abscess, and cavernous sinus thrombosis. Figure 2 illustrates the difference between periorbital (preseptal) and orbital cellulitis, as well as its complications.

Figure 2. Orbital anatomy and potential complications from orbital cellulitis. Retrieved from https://www.merckmanuals.com/professional/eye-disorders/orbital-diseases/preseptal-and-orbital-cellulitis

Any patient with unilateral eyelid edema should be evaluated for red flags of orbital cellulitis, given its potential seriousness. Red flag signs and symptoms include:3,4

  • Painful or restricted extraocular movements
  • Reduced visual acuity
  • Relevant afferent pupillary defect
  • Diplopia
  • Proptosis
  • Chemosis
  • Severe headache

 

Differential Diagnosis

Other considerations for the differential diagnosis in a unilateral, swollen red eye include:5

  • Periorbital ecchymosis due to blunt trauma
  • Contact dermatitis secondary to local irritant
  • Atopic dermatitis due to allergic sensitivity
  • Orbital tumors

 

Risk Factors

Risk factors for periorbital and orbital cellulitis include:6

  • Sinusitis
  • Dental infection
  • Insect bite
  • Trauma

 

Periorbital cellulitis is most commonly caused by an insect bite in children, and trauma in adults. Comparatively, orbital cellulitis is most often the result of trauma in children, and sinusitis in adults.

 

Diagnostic Investigations

Patients who are febrile or appear unwell should have early initiation of IV antibiotics following blood cultures. Though periorbital cellulitis is a clinical diagnosis, if there is suspicion for orbital cellulitis a CT scan of the orbits and sinuses is the gold standard. Positive findings include inflammation of extraocular muscles, anterior globe displacement, and fat stranding. Inflammation of the sinuses should not be used to differentiate periorbital from orbital cellulitis, as up to 41% of cases of periorbital cellulitis may have CT evidence of sinusitis. Figure 3 displays a labelled CT image with common findings in orbital cellulitis.7

 

Figure 3. Orbital CT image with labels. Retrieved from https://ctscanmachines.blogspot.com/2018/07/ct-scan-of-periorbital-cellulitis.html

In addition to CT imaging, there may be a role for point of care ultrasound (PoCUS) in the diagnosis and management of periorbital and orbital cellulitis. However, research is currently lacking on whether its use may avoid the need for further diagnostic imaging.8 Findings from pediatric emergency medicine suggest that orbital ultrasound may be preferred in evaluating young patients who are unable to cooperate with a thorough physical examination.9 One important application of orbital PoCUS is in the assessment of orbital abscesses. Subperiosteal abscesses may complicate more than 50% of cases of orbital cellulitis, and are not reliably detected by CT.10 Additionally, orbital ultrasound may be an appropriate alternative in settings where advanced imaging is not available, in order to guide early initiation of antibiotics.

Orbital Abscess from – The PoCUS Atlas

 

 

Treatment Best Practices  

Antibiotic choice should be guided by local susceptibility guidelines. An appropriate choice would cover S. aureus, S. pyogenes, and anaerobes.11,12 In this case, we initiated intravenous ceftriaxone and metronidazole while awaiting CT results.

The following therapeutic guidelines are from Bugs and Drugs – It is recommended that that guidelines for therapy are accessed directly from their website or from other reputable sources.

Periorbital Cellulitis

 

Orbital Cellulitis

From Bug and Drugs

 

Case Conclusion

Given this patient’s complaint of increased pain with extraocular movement, a CT orbit was performed. Fortunately, there were no signs of orbital cellulitis. The patient was treated with IV ceftriaxone and metronidazole and scheduled to return to the emergency department the next day for re-evaluation and consideration of step-down to oral antibiotics.

Summary

Orbital cellulitis is a serious condition that should be carefully distinguished from periorbital cellulitis. On history, clinicians should ensure they inquire about recent sinus or dental infections, trauma to the orbit, or possible insect bites. Physical exam should carefully assess for signs of orbital cellulitis, including proptosis, chemosis, and limited extraocular movements. Any positive red flag or clinical suspicion warrants a CT scan of the orbits and sinuses to exclude orbital cellulitis.

Further Reading

Great photo article in Canadian Family Physician

Management algorithm

Patient Information Leaflet

 

 

 

References

  1. Preseptal and Orbital Cellulitis – Eye Disorders – Merck Manuals Professional Edition. (n.d.).Retrieved January 12, 2021, from https://www.merckmanuals.com/professional/eye-disorders/orbital-diseases/preseptal-and-orbital-cellulitis
  2. Lightning Learning: Orbital Cellulitis — #EM3: East Midlands Emergency Medicine Educational Media. (n.d.). Retrieved January 12, 2021, from https://em3.org.uk/foamed/7/5/2019/lightning-learning-orbital-cellulitis
  3. Periorbital cellulitis — entsho.com. (n.d.). Retrieved January 12, 2021, from https://entsho.com/periorbital-cellulitis
  4. Distinguishing Periorbital from Orbital Cellulitis. (2003). American Family Physician, 67(6), 1349.
  5. Differential Diagnosis of the Swollen Red Eyelid – American Family Physician. (n.d.). Retrieved January 12, 2021, from https://www.aafp.org/afp/2015/0715/p106.html
  6. Risk factors of preseptal and orbital cellulitis – PubMed. (n.d.). Retrieved January 12, 2021, from https://pubmed.ncbi.nlm.nih.gov/19149979/
  7. Ct Scan Of Periorbital Cellulitis – ct scan machine. (n.d.). Retrieved January 12, 2021, from https://ctscanmachines.blogspot.com/2018/07/ct-scan-of-periorbital-cellulitis.html
  8. Kang, T. L., Seif, D., Chilstrom, M., & Mailhot, T. (2014). Ocular ultrasound identifies early orbital cellulitis. Western Journal of Emergency Medicine, 15(4), 394. https://doi.org/10.5811/westjem.2014.4.22007
  9. Seguin, J., Le, C.-K., Fischer, J. W., Tessaro, M. O., & Berant, R. (2019). Ocular Point-of-Care Ultrasound in the Pediatric Emergency Department. Pediatric Emergency Care, 35(3), E53–E58. https://doi.org/10.1097/PEC.0000000000001762
  10. Derr, C., & Shah, A. (2012). Bedside ultrasound in the diagnosis of orbital cellulitis and orbital abscess. Emergency Radiology, 19(3), 265–267. https://doi.org/10.1007/s10140-011-0993-0
  11. Orbital Cellulitis – StatPearls – NCBI Bookshelf. (n.d.). Retrieved January 12, 2021, from https://www.ncbi.nlm.nih.gov/books/NBK507901/
  12. Periorbital Cellulitis – StatPearls – NCBI Bookshelf. (n.d.). Retrieved January 12, 2021, from https://www.ncbi.nlm.nih.gov/books/NBK470408/
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A Case of Ectopic Pregnancy

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Medical Student Clinical Pearl – December 2020

Marisa O’Brien

@mbob58

MD Candidate, Class of 2021

Memorial University of Newfoundland

Reviewed and Edited by Dr. David Lewis

All case histories are illustrative and not based on any individual

 

Case Report

A 36-year-old G2P1 female presented to the Emergency Department following a pre-syncopal episode at work. The patient noted a sudden onset of significant abdominal cramping, nausea, and vaginal bleeding with clots that morning followed by an episode of lightheadedness while sitting at her desk. The patient denied any loss of consciousness, no dyspnea, no chest pain, no palpitations, and no fevers/chills. She had no known allergies and no current medications. She was a non-smoker and denied any alcohol or drug usage.

The patient’s past medical history was significant for recent treatment with methotrexate for an ectopic pregnancy eight days prior. The patient had a history of amenorrhea for 7 weeks and a serum β-hCG of 302 mlU/mL at that time. A transvaginal ultrasound was performed at 8 weeks for abdominal pain and light spotting which revealed an IUD in situ with no evidence of an intrauterine pregnancy. An early ectopic pregnancy was diagnosed and the patient was consented to receive medical management with methotrexate. She was followed up with serial β-hCG’s which gradually, but slowly, trended down to 110 mIU/ml by day 6. The patient noted slight abdominal cramping and PV bleeding following the methotrexate however this had settled after 3 days with no ongoing symptoms until today.

On initial assessment, the patient appeared well, no acute distress, and all vital signs were stable.  The abdominal exam revealed bowel sounds present in all four quadrants and the abdomen was tympanic to percussion. On palpation the abdomen was soft and nondistended with LLQ and suprapubic tenderness however, no guarding or rebound tenderness was appreciated.

Initial investigations included a CBC, β-hCG, PT & PTT, type and screen, urinalysis, EKG, & POCUS.

 

Definition

An ectopic pregnancy occurs when a fertilized egg implants at a site other then the endometrium of the uterus, most commonly the fallopian tubes. They often present as vaginal bleeding and/or abdominal pain in the setting of a positive β-hCG.1

A critical complication is a ruptured ectopic pregnancy which occurs by erosion through the tissue the zygote has implanted in resulting in intraabdominal bleeding from the exposed vessel and possible hypovolemic shock.2 Rupture should be suspected in patients presenting with hemodynamic instability including syncope, hypotension, and tachycardia. However, young healthy females may appear vitally stable initially due to compensatory mechanisms. Additional physical exam findings suggestive of a ruptured ectopic pregnancy include severe abdominal pain with guarding or rebound tenderness and abdominal distention. Pain may radiate to the shoulder due to irritation of the diaphragm from blood in the peritoneal cavity.1,3

 

Risk factors for ectopic pregnancy4

  • Previous ectopic pregnancy
  • Prior fallopian tube surgery
  • Previous pelvic or abdominal surgery
  • Sexually transmitted infections
  • Pelvic inflammatory disease
  • Endometriosis
  • Cigarette smoking
  • Maternal age > 35 years
  • History of infertility
  • Assisted reproductive technology (IVF)

 

 

Differential diagnosis for vaginal bleeding in early pregnancy1:

  • Physiologic
  • Spontaneous abortion
  • Cervical, vaginal, or uterine pathology
  • Subchorionic hematoma
  • Heterotopic pregnancy
  • Gestational trophoblastic disease

 

Sonography

According to the discriminatory zones, an intrauterine pregnancy is expected to be visualized on a transvaginal ultrasound at β-hCG levels of 1500 – 2000 mlU/mL and on a transabdominal ultrasound at levels of 4000 – 6500 mlU/mL.5

Gestational Age Β-hCG range (mlU/mL)
<1 week 5 – 50
1-2 weeks 50 – 500
2-3 weeks 100 – 5000
3-4 weeks 500 – 10,000
4-5 weeks 1000 – 50,000
5-6 weeks 10,000 – 100,000
6-8 weeks 15,000 – 200,000
8-12 weeks 10,000 – 100,000

Table 1: Estimated β-hCG levels in relation to gestational age.3

In the first trimester of a normal pregnancy, the serum β-hCG should increase by ≥ 53% every 48 hrs until 41 days of gestation.1,3 Serum β-hCG will then continue to rise more slowly until approximately 10 weeks after which it will begin to decline until reaching a plateau. Serum β-hCG levels are noted to raise more slowly in an ectopic pregnancy, thus a slower rate of increase, plateau, or decline in serum β-hCG in the first 41 days suggests a possible miscarriage or ectopic pregnancy.1

Note on β-hCG Discriminatory Zones

The value of discriminatory zones in the emergency management of ectopic pregnancy is low, with many considering it unreliable and potentially dangerous. In short, a low β-hCG does not exclude an ectopic. This useful post provides a good summary on ectopic rule-out in the ED:

Rule Out Ectopic in the Emergency Department

 

An intrauterine pregnancy is confirmed by visualization of a gestational sac and a yolk sac within the uterus (juxtaposed to bladder).1 A gestational sac alone is not sufficient for diagnoses of an intrauterine pregnancy as it may be a pseudogestational sac formed by hormonal stimulation from an ectopic pregnancy.5 Additionally, if an intrauterine pregnancy is visualized, a heterotopic pregnancy should also be considered.1 The risk of heterotopic pregnancy when conceived normally is estimated to be 1 in 30,000.

Figure 1: Visualization of an intrauterine pregnancy on a transvaginal ultrasound.3

 

 

Structure Transvaginal Ultrasound Transabdominal Ultrasound
Gestational Sac 4.5-5 weeks 5.5-6 weeks
Yolk Sac 5-5.5 weeks 6-6.5 weeks
Fetal Pole 5.5-6 weeks 7 weeks
Cardiac Activity 6 weeks 7 weeks
Fetal Parts 8 weeks >8 weeks

Table 2: Ultrasound findings based on gestational age.5

 

Diagnosis of Ectopic Pregnancy

An ectopic pregnancy is suspected in all women with a positive pregnancy test when no intrauterine pregnancy is visualized on ultrasonography. A low β-hCG or declining β-hCG does not exclude an ectopic. Ultrasound findings of an ectopic pregnancy may include an extrauterine gestational sac or embryonic cardiac activity outside of the uterus, a complex adnexal mass, or intraperitoneal fluid.3

From emupdates.com

 

Management of Ectopic Pregnancy

Is the patient unstable?

  • If the patient is hemodynamically unstable (tachycardia or hypotension or pale or syncopal) then commence immediate resuscitation (IV Access, CBC, type & crossmatch,  iv fluids, transfusion, etc) and stat consult to ObGyn.

In stable patients

  • Consult ObGyn
  • The gold-standard of treatment for ectopic pregnancy is surgical management however, treatment options include expectant, or medical management.6 Medical management with methotrexate, a folic acid antagonist that inhibits DNA synthesis and cell production, has a higher success rate when initiated at lower β-hCG levels. Methotraxate is initiated if β-hCG is <5000 mlU/mL and is reserved for those with reliable follow up as β-hCG levels are required to be trended until they are undetectable. Individuals with renal disease, hepatic disease, active pulmonary disease, or immunodeficiencies are not candidates for methotrexate.3,7 Individuals who do not meet the criteria for medical management, are hemodynamically unstable, have failed methotrexate, or a ruptured ectopic is suspected, will receive surgical management.6

 

Case Report Continued

The patient was hemodynamically stable on presentation. Her vital signs were normal. As part of the initial assessment, PoCUS was used to further evaluate for the presence of free fluid in the abdomen or pelvis. Free fluid was identified in the RUQ in both Morrison’s pouch and surrounding the caudal tip of the liver. Intraperitoneal fluid was also seen in the LUQ in both the subphrenic and splenorenal spaces. Free fluid was also visualized in Douglas’ pouch in the pelvic view.

RUQ

LUQ

Pelvis

 

Throughout the PoCUS examination the patient remained well appearing, however she had become hypotensive with a blood pressure of 90/53 mmHg. Her initial bloodwork had come back at this time revealing a β-hCG of 32 mlU/mL and a Hgb of 67 g/L. The patient received 1g of TXA, and a 1L bolus of normal saline while PRBC’s were ordered. She was documented to be Rh+ thus, she did not require RhoGAM (anti-D immune globulin). An urgent consultation to Obstetrics and Gynecology was made following the visualization of intraabdominal fluid and the patient underwent an exploratory laparotomy shortly after.

 

Key Points

  • Ectopic pregnancy should be considered in the differential diagnosis of any female patient, of childbearing age, presenting with abdominal pain, syncope or shock
  • An Intrauterine contraceptive device does not exclude an ectopic
  • Unless a previous ultrasound has documented the presence of an intrauterine pregnancy, an empty uterus in a patient with a positive pregnancy test should be considered to be a possible ectopic until ruled out
  • An intrauterine pregnancy on ultrasound requires the following to be confirmed:
    • A gestational sac and a yolk sac, in the uterus which is juxtaposed to the bladder
    • or a gestational sac containing a normal fetal pole, in the uterus which is juxtaposed to the bladder
  • A low β-hCG or declining β-hCG does not exclude an ectopic
  • Medical management of ectopic pregnancy with methotrexate requires close follow-up. Failure can occur. Ruptured ectopic pregnancy can still occur.

 

Further Reading

Ectopic Pregnancy and Ruptured Ectopic: Pitfalls in Diagnosis

ED Rounds – Early Pregnancy

The Pregnant ED Patient – A Compendium of Pearls

 

 

References

  1. Tulandi, T. (2020, November 2). Ectopic pregnancy: Clinical manifestations and diagnosis. Retrieved from: https://www.uptodate.com/contents/ectopic-pregnancy-clinical-manifestations-and-diagnosis?search=ectopic%20pregnancy&source=search_result&selectedTitle=1~150&usage_type=default&display_rank=1#H1
  2. Toy, E.C., Simon, B.C., Takenaka, K.Y., Liu, T.H., & Rosh, A.J. (2017). Ectopic Pregnancy. Case Files Emergency Medicine. (4th, pp. 369-376). McGraw-Hill Education.
  3. Hang, B.S. (2016). Obstetrics and Gynecology. Tintinalli’s Emergency Medicine: A Comprehensive Guide. (8th, pp. 629-633). McGraw-Hill Education.
  4. The American College of Obstetricians and Gynecologists. (2018, February). Retrieved from: https://www.acog.org/womens-health/faqs/ectopic-pregnancy
  5. Leonard, N.J. (2019, January 23). The Pregnant Pelvic POCUS. EMRounds. Retrieved from: https://emrounds.org/the-pregnant-pelvic-pocus/
  6. Tulandi, T. (2020, March 31). Ectopic pregnancy: Choosing a treatment. Retrieved from: https://www.uptodate.com/contents/ectopic-pregnancy-choosing-a-treatment?search=ectopic%20pregnancy&topicRef=5407&source=see_link#H2976630177
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Skin and Soft Tissue Infections: A PoCUS Guided Approach

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Medical Student Clinical Pearl – November 2020

 

Robert Hanlon

@roberthanlon12

Year: 4
DMNB Class of 2021
 

Reviewed and Edited by Dr. David Lewis

All case histories are illustrative and not based on any individual

 

Case Report

A 25yr old male presents with a 3 day history of a red swollen foot following an insect bite. He has no past medical history. On examination there is some erythema and swelling on the dorsum of the left foot. Palpation is very tender.

You are aware of recommended guidelines that advise I&D for purulent infections and decide to proceed with the procedure. Despite trying to freeze the area with lidocaine, the procedure is still painful and no pus is drained. You point to the minimal serosanguinous exudate and sheepishly suggest to the patient that the I&D was successful and that a course of antibiotics will resolve this issue.

Skin and Soft Tissue Infections: A POCUS Guided Approach

Skin and soft tissue infections (SSTIs) have a variety of potential causes, ranging in severity from mild infections like cellulitis to abscess all the way to life-threatening causes like necrotizing fasciitis.1 SSTIs are commonly encountered in the emergency department, with cellulitis and abscesses being the two most common.2 It is important to be able to recognize SSTIs and provide appropriate treatment. Abscesses require invasive management, whereas cellulitis is treated with systemic therapies; therefore, it is important to be able distinguish the different between the two types. Doing so can be difficult because of the hidden nature of abscesses. However, ultrasound can be a useful tool in establishing the presence of an abscess. This article is a review of the clinical approach and treatment for SSTIs, focusing on cellulitis and abscesses, as well as the use of ultrasound in helping to establish the diagnosis.

Approach

Clinical suspicion is the initial step in the diagnosis of SSTIs. These infections have multiple causes; therefore, obtaining a detailed history is crucial. Information about immunocompromised state, place of residence, travel, any recent trauma or surgery, previous antimicrobial use, lifestyle, hobbies, and animal bites is essential to developing an adequate differential diagnosis.3

A good understanding of the normal skin flora and common infectious organisms is key to assessing SSTIs. The most commons organisms implicated in SSTIs are Staphylococcus aureus and Streptococcus species.4-6 Methicillin resistant S. aureus (MRSA) being an important strain that has increased in prevalence in the past 20 years. Risk factors such as presence of abscess, intravenous drug use, previous MRSA status, antibiotics within 8 weeks, diabetes mellitus, and previous hospital admission within the last year increase the likelihood of the infection being cause by MRSA.4-6

Physical examination findings are crucial for establishing the presence of an SSTI; the typical criteria are a superficial lesion with the classic inflammatory findings of redness (rubor), swelling (tumor), warmth (calor), and pain (dolor).1,2,7 An abscess is defined as a fluctuant mass of puss localized and buried within a tissue, organ, or potential space; however, clinically it can be hard to determine to presence of this mass.2,7 Other associated signs and symptoms, such as crepitus, bullae, and hemorrhage, may be present upon diagnosis or may develop later during the course.2,7 Due to overlapping clinical presentations of the different SSTIs, it can be difficult to differentiate between them.

Cellulitis – No Abscess
Cellulitis – Possible Abscess
Abscess
Early Abscess

Assessment with POCUS:

Due to the similarities between different SSTI cutaneous findings and their different treatments, it is important to establish if there is an abscess present. It was common, before the introduction of ultrasound, to perform a blind needle aspiration of the infected area in order to determine the presence/absence of an abscess.8,9 However, this subjects that patient to the risks of an invasive procedure as well as pain. On the other hand, treating infection with empiric antibiotics in the presence of an unknown abscess delays drainage and allows for potential worsening of the infection.8,9

A study by Tayal et al. demonstrated that the use of ultrasound was beneficial in patients who had both low and high pretest probability for needing incision and drainage. In patients suspected of having simple cellulitis (low pretest), ultrasound was used to change management in over half of participants; establishing the need for drainage due to imaging of a fluid collection. The opposite was true in the patients suspected of having an abscess (high pretest); the study found that ultrasound was able to determine that more than half of this group did not need drainage, because of the absence of a fluid collection on imaging.10 Other studies have had similar findings, but the percent change in management was slightly lower.11

A study by Barbic et al. demonstrated that POCUS provided a rapid, non-invasive, painless, and easily repeatable test, that distinguished between abscess and cellulitis in the vast majority of cases. Their analysis concluded that POCUS had a sensitivity of 96.2% and a specificity of 82.9% in diagnosing the presence of an abscess.12 They concluded that POCUS can accurately diagnose abscess in paediatric and adult populations and is likely superior to clinical examination.12

Cobblestones

Classic finding for cellulitis (but not specific to cellulitis). There will be hyperechoic lobules of subcutaneous fat surrounded by relatively hypoechoic inflammatory fluid.13

Cobblestone – Cellulitis

Purulent Fluid Collection

Classic finding for an abscess; have a rounded shape of anechoic or hypoechoic fluid collection, and there will be surrounding areas of cobblestones from the overlying cellulitis.13 As well, there should be no color flow if doppler is applied to the area (helping to distinguish from lymph node or vessel).14

Abscess – Anechoic Collection
Possible Abscess or Lymph Node? – This is a lymph node – see below
Colour flow differentiates lymph node from abscess

Necrotizing Fasciitis

Because you do not want to miss it! Findings via ‘STAFF’; subcutaneous thickening, air, and fascial fluid.14 Note, that ultrasound does not to exclude the diagnosis. Also need clinical correlation to increase suspicion of such a serious infection.15

Necrotizing Fasciitis – STAFF

Treatment:

According to The Infectious Diseases Society of America (2014) guidelines, management of SSTIs is differentiated based on the presence/absence of purulence (i.e. abscess/fluid collection). They recommend that all purulent infections be treated with incision and drainage, with more severe infections (signs of systemic involvement) being cultured with sensitivities in order to add antibiotics to the treatment.16 Otherwise, non-purulent infections are to be treated with systemic antibiotics; the severity of the infection determining the route and choice of agent.16

Antibiotic therapy, in addition to incision and drainage of a skin abscess, is suggested for patients with any of the following:17

  • Single abscess ≥2 cm or multiple abscesses
  • Large are of surrounding cellulitis
  • Patients with immunosuppression or other comorbidities
  • Signs of systemic involvement (fever > 38°C, hypotension, or tachycardia)
  • Poor clinical response to incision and drainage alone
  • Presence of an indwelling medical device
  • High risk for adverse outcomes with endocarditis (these include a history of infective endocarditis, presence of prosthetic valve or prosthetic perivalvular material, unrepaired congenital heart defect, or valvular dysfunction in a transplanted heart)
  • High risk for transmission of aureus to others (such as in athletes or military personnel)

 

Horizon Health’s local trends recommend the following (see guideline or Spectrum app for full details)

Severity of Infection

 

 

Antibiotic

Mild

Moderate

Severe

Cephalexin 500 – 1000mg PO q6h x 5 days

ceFAZolin 2 g IV q8h x 5 days

ceFAZolin 2 g IV q8h +/- Clindamycin 900 mg IV q8h

If true beta-lactam allergy

Cefuroxime 500 mg PO BID or TID x 5 days

Clindamycin 600-900 mg IV q8h x5 days

 

If MRSA suspected

Septra 800/160 mg or 1600/320 mg PO q12h x 5 days

Vancomycin 25-30 mg/kg IV once then 15mg/kg IV q8 to q12h x 5 days

ADD Vancomycin 25-30 mg/kg IV once then 15mg/kg IV q8 to q12h

 

Some research is suggesting that POCUS can take the assessment of abscesses one step-further and impact management based on the depth and size of the fluid collection seen in imaging. Russell et al. found that abscesses less than 0.4cm below the skin surface could be effectively treated without incision and drainage.18 Another study found that patients, with skin abscesses less than or equal to 5cm in diameter, treatment with oral antibiotics in combination with incision and drainage had improved short-term outcomes compared to those patients treated with the procedure alone.18 While as mentioned above, UpToDate, suggests that antibiotics be used in single abscess greater than 2 cm in size. As well, research has found that ultrasound guided incision and drainage provides lower failure rates (less recurrent infections or multiple incisions) compared to blind incision and drainage. Likely due to better visualization of the abscess and more adequate initial drainage.19

Limitations

There are some limitations to POCUS for SSTIs: ultrasound imaging and interpretation rely on the user’s ability to obtain high-quality images in order to assess whether an abscess is present. It is important for the user to be familiar with different findings on ultrasound to guide appropriate treatment. An abscess may appear hypoechoic, hyperechoic, or anechoic (depending on tissue contents), and usually has posterior acoustic enhancement.19 Determining if it is drainable can be difficult due to this variability in imaging, and it is also quite common for early abscesses to present like cellulitis with erythema, no fluctuance, and an ultrasound that is negative for a fluid collection.20 In cases of a suspected evolving abscess, sometimes referred to as a non-ripe abscess, supportive care, including warm compresses, pain control, and close follow-up, is recommended.20 The practitioner may treat this like cellulitis; however, the patient may return with perceived failure of therapy if discharge advice does not include the possibility of of an abscess forming over time.

Abscess examples from the SJ archives

  • Drainable abscess – Note the anechoic collection with some dependent debris
  • Beard abscess – note the anechoic collection and hyperechoic hair
  • Deep abscess – swirling echoic debris = “pustulasis”
  • Small abscess – another example of “pustulasis”
  • Cellulitis – starting to coalesce but not drainable yet
  • Large abscess in groin – what are those deeper structures?
  • Femoral vessels just deep to groin abscess
  • Large abscess – thick hyperechoic pus
  • Hip incision abscess – thick hyperechoic pus
  • Ischiorectal abscess
  • Lymph node
  • Pilonidal abscess – note the hyperechoic hair
  • Cellulitis – coalesced abscess – drainable

References

  1. Moffarah AS, Al Mohajer M, Hurwitz BL, Armstrong DG. Skin and Soft Tissue Infections. Microbiol Spectr. 2016 Aug;4(4). doi: 10.1128/microbiolspec.DMIH2-0014-2015.

 

  1. Martinez, N. “Skin and Soft-Tissue Infections: Itʼs More Than Just Skin Deep.” Advanced Emergency Nursing Journal, vol. 42, no. 3, 2020, pp. 196–203.

 

  1. Cieri, B., Conway, E., Sellick, J., & Mergenhagen, K. (2019). Identification of risk factors for failure in patients with skin and soft tissue infections. The American Journal of Emergency Medicine, 37(1), 48-52.

 

  1. Borgundvaag, B., Ng, W., Rowe, B., Katz, K., Farrell, Brian, Guimont, Chantal, . . . Gregson, Dan. (2013). Prevalence of methicillin-resistant Staphylococcus aureus in skin and soft tissue infections in patients presenting to Canadian emergency departments. CJEM, 15(3), 141-160.

 

  1. Esposito, S., De Simone, G., Pan, A., Brambilla, P., Gattuso, G., Mastroianni, C., . . . Savalli, F. (2019). Epidemiology and Microbiology of Skin and Soft Tissue Infections: Preliminary Results of a National Registry. Journal of Chemotherapy (Florence), 31(1), 9-14.

 

  1. Stenstrom, R., Grafstein, E., Romney, M., Fahimi, J., Harris, D., Hunte, G., . . . Christenson, J. (2009). Prevalence of and risk factors for methicillin-resistant Staphylococcus aureus skin and soft tissue infection in a Canadian emergency department. CJEM, 11(5), 430-8.

 

  1. Spelman, D., Baddour, LM. (2020). Cellulitis and skin abscess: Epidemiology, microbiology, clinical manifestations, and diagnosis In: UpToDate, Post TW (Ed), UpToDate, Waltham, MA. Retrieved November 11, 2020. From: https://www.uptodate.com/contents/cellulitis-and-skin-abscess-epidemiology-microbiology-clinical-manifestations-and-diagnosis?search=abscess%20treatment&topicRef=110530&source=see_link#H2443336514

 

  1. Comer, Amanda B. “Point-of-Care Ultrasound for Skin and Soft Tissue Infections.” Advanced Emergency Nursing Journal, vol. 40, no. 4, 2018, pp. 296–303.

 

  1. Gaspari, R., Sanseverino, A., & Gleeson, T. (2019). Abscess Incision and Drainage With or Without Ultrasonography: A Randomized Controlled Trial. Annals of Emergency Medicine, 73(1), 1-7.

 

  1. Tayal, V., Hasan, N., Norton, H., & Tomaszewski, C. (2006). The Effect of Soft‐tissue Ultrasound on the Management of Cellulitis in the Emergency Department. Academic Emergency Medicine, 13(4), 384-388.

 

  1. Alsaawi, A., Alrajhi, K., Alshehri, A., Ababtain, A., & Alsolamy, S. (2017). Ultrasonography for the diagnosis of patients with clinically suspected skin and soft tissue infections: A systematic review of the literature. European Journal of Emergency Medicine, 24(3), 162-169.

 

  1. Barbic, D., Chenkin, J., Cho, D., Jelic, T., & Scheuermeyer, F. (2017). In patients presenting to the emergency department with skin and soft tissue infections what is the diagnostic accuracy of point-of-care ultrasonography for the diagnosis of abscess compared to the current standard of care? A systematic review and meta-analysis. BMJ Open, 7(1), E013688.

 

  1. Atkinson DP, Bowra J, Harris T, Jarman B, Lewis D, editors. Point of Care Ultrasound for Emergency Medicine and Resuscitation. Oxford University Press; 2019. pp. 140, 199-200.

 

  1. Gottlieb, M., Schmitz, G., Grock, A., & Mason, J. (2018). What to Do After You Cut: Recommendations for Abscess Management in the Emergency Setting. Annals of Emergency Medicine, 71(1), 31-33.

 

  1. Castleberg, E., Jenson, N., & Dinh, V. (2014). Diagnosis of necrotizing faciitis with bedside ultrasound: The STAFF Exam. The Western Journal of Emergency Medicine, 15(1), 111-113.

 

  1. Stevens, D., Bisno, A., Chambers, H., Dellinger, E., Goldstein, E., Gorbach, S., . . . Wade, J. (2014). Practice guidelines for the diagnosis and management of skin and soft tissue infections: 2014 update by the infectious diseases society of America. Clinical Infectious Diseases : An Official Publication of the Infectious Diseases Society of America, 59(2), 147-159.

 

  1. Spelman, D., Baddour, LM. (2020). Cellulitis and skin abscess in adults: treatment. In: UpToDate, Post TW (Ed), UpToDate, Waltham, MA. Retrieved November 11, 2020. From: https://www.uptodate.com/contents/cellulitis-and-skin-abscess-in-adults-treatment?search=abscess%20treatment&topicRef=110529&source=see_link

 

  1. Russell, F., Rutz, M., Rood, L., Mcgee, J., & Sarmiento, E. (2020). Abscess Size and Depth on Ultrasound and Association with Treatment Failure without Drainage. The Western Journal of Emergency Medicine, 21(2), 336-342.

 

  1. Gaspari, R., Sanseverino, A., & Gleeson, T. (2019). Abscess Incision and Drainage With or Without Ultrasonography: A Randomized Controlled Trial. Annals of Emergency Medicine, 73(1), 1-7.

 

  1. Thornton J, Hellmich T. Evaluation and Management of Abscesses in the Emergency Department. Emergency Medicine Reports. 2017 May 1;38(10).
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EM Reflections October 2020 – Spinal Cord Injury

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Big thanks to Dr. Joanna Middleton for leading the discussions in October

All cases are imaginary, but highlight learning points that have been identified as potential issues during rounds.

Edited by Dr. Mandy Peach

Spinal Cord Injury

  • Recognition of various patterns of spinal cord injury
  • Reviewing EMS record can be helpful for progression of symptoms and baseline exam
  • A normal CT does not rule out spinal cord injury in a patient with neurological deficits
  • Importance of detailed neurological exam and clear communication with consultant
  • Importance of clear documentation of exam – consider using ASIA

Case

A 72 yo female presents complaining of bilateral arm weakness ongoing for 1 day. She has no other symptoms concerning for stroke. She denies any direct trauma to head or neck, but did say she was pushed from behind by a large dog and her neck ‘snapped back’ the day prior. Incidentally she says she also hasn’t urinated in over 8 hours. Her vital signs are within normal limits.

 

You are concerned about a spinal cord injury – what are the various cord syndromes? What in the history predisposes to a particular spinal cord syndrome?

4 Classification of spinal cord syndromes

This woman is elderly, likely with underlying cervical spondylosis, and has a hyperextension injury – predisposing her to a central cord syndrome. This is the most common type of incomplete spinal cord injury. Often these patients are asymptomatic from their spondylosis before the event and the mechanism of injury is usually not severe5.

Central cord syndrome involves both motor and sensory pathways and has a variable presentation. Typically one sees motor weakness in the hands and forearms with sensory preservation. Bladder dysfunction and sexual dysfunction can be seen in severe cases5. A helpful mnemonic is MUD-E6.

 

MUD-E

  • Motor loss > sensory loss
  • UE > LE
  • Distal > proximal
  • Extension type injury

 

You complete a detailed neurological exam and find she does have upper limb weakness distally. A bladder scan confirms urinary retention with 850 cc of urine in her bladder.

You decide to order a CT C -spine to assess for bony injuries. The CT scan is unremarkable.

Does this rule out a spinal cord injury in this patient?

No – normal CT does not rule out SCI in a patient with ongoing neurological deficits. In fact, in elderly patients there is often no bony injury, but the narrowed spinal canal can predispose to buckling of the ligament flava, leading to injury of the spinal cord.

You review EMS notes and nursing documentation – there are subtle differences throughout in how the exam is performed and recorded.

What is one tool that can improve your documentation in terms of accuracy and clarity?

ASIA (American Spinal Injury Association) Classification

You document your findings on ASIA, which allows for clearer communication and documentation with the attending neurosurgeon.

 

References for further reading:

4 Perron & Huff (2010). Chapter 104 Spinal Cord Disorders. Rosen’s Emergency Medicine: Concepts and Clinical Practice. pp 1389-1397. Philadephia, PA

5  Douglas, Nowak et al. (2009). Review article: Central Cord Syndrome. Journal of the American Academy of Orthopedic Surgeons. 17: 756-765

6 A boring guide to spinal cord syndromes. CanadiamEM. https://canadiem.org/a-boring-guide-to-spinal-cord-syndromes/

 

Authored and Edited by Dr. Mandy Peach

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