Adventures in cross-cover: Atrial Fibrillation

Its 3 am and you are paged about a patient with atrial fibrillation and a rapid ventricular response. As you head to the patient’s room, it may become easier to make a clinical decision with an algorithm already in mind. The ACC/AHA/HRS 2014 guidelines and the CHEST guidelines on the management of atrial fibrillation suggest a few branch points in the decision tree:

A fib acute mgmt

Definition and Implications of Atrial Fibrillation

For two days in a row, we have had excellent case-based discussions regarding patients with atrial fibrillation. This raised several important questions about the diagnosis, management, and complications of this common atrial arrhythmia. Before we get into the details, lets start with some definitions:

Simplified definition of Atrial Fibrillation (AF):

Afib definition

Beyond the definition, it is important to understand the clinical implications of atrial fibrillation:

Clinical implications of AF

Zoster Ophthalmicus

  • Herpes zoster (or shingles) is due to reactivation of endogenous latent VZV within the sensory ganglia.
  • Rash typically starts as erythematous papules that evolve into grouped vesicles and can become more pustular and hemorrhagic by day 4 in a single or multiple dermatome pattern.
  • Lesions tend to crust by days 7-10 and are considered no longer infectious.
  • Herpes zoster ophthalmicus is a potentially serious sight-threatening condition linked to VZV reactivation of trigeminal ganglion.
  • Typically involves the ophthalmic branch of cranial nerve V.
  • 50-72% of patients with ophthalmicus will have direct ocular involvement: conjunctivitis, episcleritis, iritis, keratitis, lid droop.
  • Vesicular lesions on nose are associated with high risk of zoster ophthalmicus – Hutchinson’s Sign.
  • Typically it is a clinical diagnosis but can perform Tzanck smear of vesicle, viral culture, or VZV PCR.
  • Ophthalmology involvement is highly recommended.
  • Antiviral therapy: oral famciclovir or valacyclovir for 7-10 days; if retinitis involvement use acyclvoir 10mg/kg IV q8h (Johns Hopkins Antibiotic Guide)
  • Adjunctive therapies: cool compresses, topical steroids (ex. Loteprednol), systemic steroids used when there’s significant edema and concern for pressure on optic nerve in periorbital region.

Radiation Pneumonitis

Risk:

  • Thoracic or neck irradiation for the treatment of malignancy (eg, breast, laryngeal, lung, hematologic)
  • Method of irradiation
  • The volume of irradiated lung
  • Total dosage and frequency of irradiation
  • Associated chemotherapy

 

Symptoms:

  • General: dyspnea, cough, chest pain, fever, and malaise
  • Subacute: usually develop approximately four to twelve weeks following irradiation
  • Late or fibrotic: radiation pneumonitis develops after six to twelve months

Physical examination:

  • Pulmonary: crackles, a pleural rub, dullness to percussion, or may be normal.
  • Skin erythema may outline the radiation port but is not predictive of the occurrence or the severity of radiation pneumonitis

Diagnosis:

  • Careful exclusion of other possible diagnoses, such as infection, thromboembolic disease, drug-induced pneumonitis, pericarditis, esophagitis, tumor progression, or tracheoesophageal fistula, is key.
  • Imaging:
    • Subacute: chest radiograph may show perivascular haziness. CT chest may show patchy alveolar ground glass or consolidative
    • Chronic: volume loss with coarse reticular or dense opacities. A straight line effect, which does not conform to anatomical units but rather to the confines of the radiation port, is virtually diagnostic of radiation-induced lung injury.

Treatment:

  • Symptomatic: typical treatment is prednisone (at least 60 mg/day) for two weeks, followed by a gradual taper
  • Asymptomatic: do not initiate treatment unless symptoms become bothersome or pulmonary function declines by more than 10 percent.
  • Patients who have established fibrosis due to prior irradiation are unlikely to benefit from glucocorticoid therapy

Ask the Expert: Dr. Bedimo on HCAP

You are on call and get a call from the ER for possible pneumonia in a patient that resides in a nursing home. How do you approach the choice of antibiotic therapy? Should this be treated as community-acquired pneumonia, or health-care associated pneumonia?

Dr. Bedimo, Chief of the Infectious Disease Division at the North Texas VA Medical Center, notes the following: “The ATS/IDSA guidelines indeed include nursing homes in the definition of Health Care Associated Pneumonia (Am J Respir Crit Care Med. 2005;171(4):388).

Healthcare-associated pneumonia (HCAP) is defined as pneumonia that occurs in a non-hospitalized patient with extensive healthcare contact, as defined by one or more of the following:

  • Intravenous therapy, wound care, or intravenous chemotherapy within the prior 30 days
  • Residence in a nursing home or other long-term care facility
  • Hospitalization in an acute care hospital for two or more days within the prior 90 days
  • Attendance at a hospital or hemodialysis clinic within the prior 30 days

However, the issue is whether these settings indeed increase the likelihood of multi-drug resistant pathogens such as MRSA and MDR Pseudomonas.  The above guidelines are dated, and there’s recent controversy over the topic.  So, newer guidelines (due anytime now) might change to likely exclude nursing home residents without recent hospital contact…”

 

 

Sepsis: More Complicated Than We Think

Yesterday at noon conference, Dr. Cutrell (Infectious Disease Division), referred to several articles that have reexamined sepsis including its mechanisms and management. Check out the articles below that Dr. Cutrell referred to:

Article written by Dr. Suffredini and Dr. Munford (former UTSW resident and faculty) in JAMA from 2011 reviewing past therapies for sepsis and potential future projects:

http://www.ncbi.nlm.nih.gov/pubmed/21750297

Article written in Proceedings of the National Academy of Sciences in the United States of America in 2013 that reevaluates the utility of murine models in understanding human diseases. Followed by a link from The New York Times that addresses this same topic:

http://www.ncbi.nlm.nih.gov/pubmed/23401516

http://www.nytimes.com/2013/02/12/science/testing-of-some-deadly-diseases-on-mice-mislead-report-says.html?pagewanted=all

Big thanks to Dr. Cutrell for the links!

Learning Lessons from Africa: Peer Health Educators

Interesting segment today on NPR: Morning Edition regarding a program in New York City looking to address chronic diseases (ie HIV, diabetes, heart disease) in a low-income community called “City Health Works”. Adopted from a model started in South Africa, this program hires people from the community as “peer health educators” who follow up with patients after they’re seen at clinic and make sure they are taking their medications or answer any other questions. These peer health educators aren’t medical professionals (ie nurses, physicians, PA’s, NP’s) but members of the community who want to help. They are considered “health coaches” and are able to visit these patients with chronic diseases and listen to them that may not be possible in a 15 minute office visit. With closer follow up of these patients, the program is hoping to see an effect on inpatient admissions/readmissions and improved compliance.

Check out the link below to read the article or listen to the segment:

http://www.npr.org/blogs/health/2014/11/24/365234329/an-african-village-inspires-a-health-care-experiment-in-new-york?utm_medium=RSS&utm_campaign=us

Q&A with Dr. Mansi

Dr. Ishak Mansi is professor in the department of medicine and clinical sciences and in the division of outcomes and health services research at UT Southwestern. He recently gave Grand Rounds and talked about studies looking at adverse events related to statins. Below is a short Q&A with Dr. Mansi as he talks about why he became interested in outcomes research and what constitutes a good study.

Q: What made you get interested in outcomes research?

I am a clinician, who practiced medicine since my graduation 33 years ago; therefore, as I interact with my patients, listen, and note their perspectives and concerns, I wonder about many of our practices and their actual impact on meaningful patients’ clinical outcomes.

We have to admit that we do “weird stuff” in the site of lay people: think about giving patients a strange looking pill that may cause symptoms and costs money, while they have no specific complaint (e.g. statins in primary prevention).


Q: Why are you interested in statin therapies and their outcomes?

I was exposed in my career to two extremes of statins utilization. The first was in Louisiana State University Health Science Center in Shreveport (LSUHSC), where patients rarely filled statin prescriptions. In LSUHSC, the institute did not have an outpatient pharmacy and our patients were too poor to afford paying for statins.

The second was in the Brooke Army Medical Center, where statins were available for free for all their population. Frequently, patients LDL-cholesterol levels were collected through electronic medical records, and were considered as quality of care measures for primary care providers. Therefore, physicians liberally prescribed statins to avoid being penalized as “poor-performers”. Living these two extremes challenged my thoughts and elicited my interest about the actual benefit/harms from these medications.  


Q: What are the characteristics/features of a well designed study that looks at outcomes? (Ex. Large cohort, prospective versus retrospective)

Clinical trials are the gold standard in establishing medication efficacy (does this drug work?); but it should be followed by other studies that establish medication effectiveness (how well this medication actually works in clinical practice for a target population). Additionally, observational studies should guide the design of future clinical trials to ensure appropriate design. In general, prospective cohort studies are better than retrospective studies, but they are also much more expensive, time consuming, and require many years before obtaining results.

A well-designed study is the one that considers all known information about a problem and sincerely attempt to answer the question at-hand, rather than attempting to prove a “premeditated outcome”  that serves a private interest.