Date: October 20th, 2021

Reference: Talan et al. Pathway with single-dose long-acting intravenous antibiotic reduces emergency department hospitalizations of patients with skin infections. AEM October 2021

Guest Skeptic: Dr. Lauren Westafer an Assistant Professor in the Department of Emergency Medicine at the University of Massachusetts Medical School – Baystate. She is the cofounder of FOAMcast and a pulmonary embolism and implementation science researcher. Dr. Westafer serves as the Social Media Editor and research methodology editor for Annals of Emergency Medicine. Lauren also recently won the SAEM FOAMed Excellence in Education Award.

Case: A 46-year-old male with a history of diabetes controlled on metformin presents with erythema and warmth to his right lower leg measuring 27 cm by 10 cm for the past four days. The patient is neurovascularly intact and there is no evidence of deep vein thrombosis (DVT) on ultrasound. He has no fever, and his white blood cell count is 12,500.

Background: Emergency department visits for skin and soft tissue infections (SSTI) are common and increasing [1]. These types of infections include cellulitis and abscesses. The SGEM has a couple of episodes on the treatment of cellulitis with antibiotics (SGEM#131 and SGEM#209).

The treatment of abscesses has been covered a few more times on the SGEM (SGEM#13, SGEM#156, SGEM#164 and SGEM#311). The latest episode looked at the loop technique to drain uncomplicated abscesses. The result was no statistical difference in failure rates between the loop and standard packing. Our conclusion was to consider using the loop technique on your next uncomplicated abscess.

Most patients can be managed as outpatients. However, the average length of stay for inpatient care is one week and costs close to $5 billion dollars a year in the USA [2]. The mortality rate for hospitalized patients with SSTI is <0.05% [3, 4].

The only reason for in-patient management in 40% of patients was to provide parenteral antibiotics [5]. This has led to greater interest in long-acting parenteral antibiotics as a possible alternative to admission. 


Clinical Question: Does the use of a clinical pathway, including a dose of intravenous dalbavancin, in emergency department patients with skin and soft tissue infections reduce hospitalizations?


Reference: Talan et al. Pathway with single-dose long-acting intravenous antibiotic reduces emergency department hospitalizations of patients with skin infections. AEM October 2021

  • Population: Patients ≥18 years old with abscess, cellulitis, or wound infection believed or confirmed to be due to gram-positive bacteria and an area of infection of at least 75 cm2.
    • Excluded: Unstable comorbidity (e.g. severe sepsis), immunosuppression, injection drug use and fever, pregnancy, breastfeeding, bilateral lower extremity involvement, severe neurologic disorder, allergy to glycopeptide antibiotics, suspected gram negative infection or infection likely to need more intensive care or broad spectrum antibiotics, suspected osteomyelitis, septic arthritis, or endocarditis.
  • Intervention: Clinical pathway included a single dose of intravenous (IV) dalbavancin
    • 1500 mg (creatinine clearance ≥30 mL/min) or 1,125 mg for creatinine clearance <30 mL/min not on dialysis
    • Telephone follow up call 24 hours after the visit and a follow up appointment 48-72 hours after discharge
  • Comparison: Usual care pre-implementation of the new clinical pathway
  • Outcome:
    • Primary Outcome: Hospitalization rate at the time of initial care in the population that received at least one antibiotic dose
    • Secondary Outcomes: Hospitalizations through 44 days, health resource utilization (length of stay, level of care, major surgical interventions, ICU admissions), adverse events, and patient-related outcomes (satisfaction, work productivity, and quality of life surveys at 14 days)
  • Trial Design: Before-and-after observational study at eleven US academic affiliated emergency departments (EDs).

Dr. David Talan

This is an SGEMHOP episode which means we have the lead author on the show. Dr. Talan is considered an authority in acute infections that result in severe morbidity and death. He is currently on the faculty of the Department of Emergency Medicine, and Department of Medicine, Division of Infectious Diseases at UCLA Medical Center. Dr. Talan also serves on the editorial board of the Annals of Emergency Medicine.

Authors’ Conclusions: Implementation of an ED SSTI clinical pathway for patient selection and follow-up that included use of a single-dose, long-acting IV antibiotic was associated with a significant reduction in hospitalization rate for stable patients with moderately severe infections.”

Quality Checklist for Observational Study:

  1. Did the study address a clearly focused issue? Yes
  2. Did the authors use an appropriate method to answer their question? Yes
  3. Was the cohort recruited in an acceptable way? Yes
  4. Was the exposure accurately measured to minimize bias? Yes
  5. Was the outcome accurately measured to minimize bias? Yes
  6. Have the authors identified all-important confounding factors? Unsure
  7. Was the follow up of subjects complete enough? Yes
  8. How precise are the results? Fairly precise
  9. Do you believe the results? Yes
  10. Can the results be applied to the local population? Unsure
  11. Do the results of this study fit with other available evidence? Yes

Results: Over 3,000 patients were screen in the before and in the after phase of this study. Only 5% were eligible for inclusion. The median age of participants was in the late 40’s, two-thirds were male, and over 80% had cellulitis.


Key Result: Less patients were hospitalized after the implementation of the new clinical pathway that included a single-dose, long-acting IV antibiotic.


  • Primary Outcome: Hospitalization rate at the time of initial care
    • 38.5% usual care vs 17.6% new pathway
    • Absolute Difference 20.8% (95% CI; 10.4% to 31.2%)
  • Secondary Outcome:
    • Hospitalizations through 44 days: Absolute Difference 16.1% (95% CI; 4.9% to 27.4%)
    • Length of Stay: 3.0 days (IQR 2.0 to 5.0) vs 2.0 days (IQR 1.0 to 4.0)
    • Infection-Related Surgery: 0.6% vs. 3.3%
    • ICU Admissions: 1.9% vs 0.7%
    • Mild, Moderate and Severe AE: Were all more common in the new pathway group
    • Deaths: None
    • Patient-Related Outcomes; These were detailed in the supplemental material

We asked David five nerdy questions about his study.  Listen to the SGEM podcast to hear his responses.

1. Inclusion/Exclusion – The patient flow diagram, Figure 1, does not list reasons for exclusion, so it’s difficult to know why patients weren’t included and if they are different than those who were excluded. Do you have any data on the characteristics of the excluded patients, and could this have led to some selection bias?

2. Study Design – Your team used a before/after study design to investigate the association between a new clinical pathway and hospitalization for patients with SSTI. One drawback to this type of design is the possible contamination of treatment effect by confounders such as other system or local factors. For example, it’s not clear how much the protocol to ensure close outpatient follow up or education contributed to the lower hospitalization rates.

3. Hawthorne Effect – In this study, clinicians in the intervention period knew they were being studied. It is possible that some portion of the treatment effect was the result of the clinicians being aware that their management of skin and soft tissue infections was being evaluated and that discharge was encouraged.

4. Impact – The pathway demonstrated an absolute difference of 21% for the primary outcome of hospitalizations. As mentioned earlier, only 5% of those screened for eligibility were enrolled. That means most patients who present with SSTI the data does not directly apply to their management. Does this not limit the impact of this intervention significantly?

5. External validity – This study was conducted in 11 academic affiliated EDs in the US. The US has a much different healthcare system than other countries like Canada, UK and Australia. Do you think this data can be applied outside the US?

The academic world is also different than community EDs. The clinical pathway included telephone follow up and an outpatient follow up visit within 48-72 hours. This may not be feasible in many community practice environments or certain patient populations.

Comment on Authors’ Conclusion Compared to SGEM Conclusion: We generally agree with the authors’ conclusions.


SGEM Bottom Line: In hospital systems with access to IV dalbavancin and the ability to establish expedited telephone and in-person follow up, this clinical pathway is associated with a decrease in hospitalizations for patients with moderately severe cellulitis.


Case Resolution: You offer the man the new long-acting single-dose IV antibiotic and outpatient management. He is happy to not need to be admitted to hospital and is discharged home with follow-up instructions.

Clinical Application: It all depends. This medication costs ~$5,000 for 1,500mg. It is unclear if this would be a cost effective strategy. There could also be a concern with indication creep leading to increased antibiotic resistance.

Dr. Lauren Westafer

What Do I Tell My Patient? You have a skin infection. Traditionally, people are often admitted to hospital for about one week to get IV antibiotics. We have a new medication that only requires one dose here in the ED. It is a long-acting antibiotic. You can go home today after the treatment. We will give you a call to make sure you are doing ok. You will also get an in-person follow-up in the next couple of days. Would you like to be admitted to hospital or be treated and sent home today?

Keener Kontest: Last episode winner was Dr. Robert McAllister. He is a new grad practicing EM in Ontario. Rob knew Plasmalyte 148 gets its name from the total mEqs.

Listen to the SGEM podcast for this weeks’ question. If you know, then send an email to thesgem@gmail.com with keener in the subject line. The first correct answer will receive a cool skeptical prize.

SGEMHOP: Now it is your turn SGEMers. What do you think of this episode on long-acting antibiotics for cellulitis? Tweet your comments using #SGEMHOP.  What questions do you have for David and her team? Ask them on the SGEM blog. The best social media feedback will be published in AEM.

Don’t forget those of you who are subscribers to Academic Emergency Medicine can head over to the AEM home page to get CME credit for this podcast and article.

Even if you are not a subscriber to AEM you can still claim CME credits for this SGEM episode. The content will always be free but there is a small fee for the CME. Thanks for supporting this free open access knowledge translation project.


Remember to be skeptical of anything you learn, even if you heard it on the Skeptics’ Guide to Emergency Medicine.


References:

1. Pallin DJ, Egan DJ, Pelletier AJ, Espinola JA, Hooper DC, Camargo CA Jr. Increased US emergency department visits for skin and soft tissue infections, and changes in antibiotic choices, during the emergence of community-associated methicillin-resistant Staphylococcus aureus. Ann Emerg Med. 2008;51:291-298.

2. Suaya JA, Mera RM, Cassidy A, et al. Incidence and cost of hospitalizations associated with Staphylococcus aureus skin and soft tissue infections in the United States from 2001 through 2009. BMC InfectDis. 2014;14:296.

3. Sabbatini AK, Nallamothu BK, Kocher KE. Reducing variation in hospital admissions from the emergency department for low-mortality conditions may produce savings. Health Aff (Millwood). 2014;33:1655-1663.

4. LaPensee KT, Fan W, Economic burden of hospitalization with antibiotic treatment for bacteremia, sepsis in the US. Paper presented at: IDWeek Annual Meeting; October 17–21, 2012; San Diego, CA

5. Talan DA, Salhi BA, Moran GJ, et al. Factors associated with decision to hospitalize emergency department patients with skin and soft tissue infection. West J Emerg Med. 2015;16:89-97.