Environmental Emergencies (March 2018)
AIR: Environmental
Articles:
- How has reading the article changed your practice?
- What information had you believed in previously that were debunked by reading this article?
- What new information did you learn from reading this article?
- What are current areas of uncertainty on this topic that can be potential areas for research?
For an Original Research Article
- What are some strengths of the study?
- What are the limitations?
- What are the main outcomes of the study?
Does reading this article change your practice? If so, how?
17 comments
Kwong et al.
Strengths: many subgroup analyses, large database from which to pull data, having access to data that allows patients to act as their own controls through risk and control intervals
Limitations: not accounting for how long between symptom onset and positive test for the flu, unclear if greater incidence of MI is flu-specific or related to other infections, no data about the severity or clinical significance of the MI
Main outcomes: hospitalization for acute MI
I think this flu season has humbled me enough that I am now more likely to admit flu + patients who are older with multiple co-morbidities to the hospital. It is unclear how long these patients should be admitted for- the risk of MI seems higher in the first few days after a positive test, but an increased risk exists even a week out. This effect may not be flu-specific, so should we admit any older adult with a URI? As with everything, it depends on how they look, how reliable they are, and risk tolerance.
Zahed
Strengths: practical application in the ED, follow up after ED discharge, baseline characteristics similar between 2 groups
Main outcome: proportion of patients with anterior packing vs TXA whose bleeding stopped in 10 minutes
Secondary outcomes: re-bleed in 24 hours and 1 week, ED LOS, and patient satisfaction
Limitations: severity was defined as continued bleeding after 20 minutes of pressure as an inclusion criteria but this type of compression varies widely and is often done incorrectly, unblended to patients and practicing physician, small study
I will try to use TXA more often and see if it is successful.
1. AMI after Flu Infection
– This study had a fairly large sample size and had a unique internal control group by using the timing of an AMI relative to flu diagnosis as an outcome. They also provided fairly strong data from prior studies to show that using AMI as a primary discharge diagnosis is fairly specific for a true AMI (93% specific), although it does make me wonder how 7% of those discharges for AMI do not represent an actual AMI.
– Retrospective study of association between flu and AMI does not mean causality. Seasonal variation could be a cofounder, although using only a 7day window after diagnosis of flu limits this.
– Incidence ratio of 6x rate of MI within first week of flu diagnosis. Unchanged by vaccination status (although this just means if a patient gets flu despite being vaccinated, then they suffer the same consequence of the flu) – does not in any way address AMI’s avoided by vaccinated patients who were protected from flu exposure.
– Because of the fairly strong incidence ratio, and our previous knowledge that pro-inflammatory states of any kind strongly predispose patients to AMI, the study is pretty convincing that patients with risk factors for AMI who test + for flu are at much high risk for subsequent AMI. In appropriately risk stratified patients who are flu+, I would say this increases the argument for admission or very close follow up, and low threshold to initiate cardiac workup at the first sign of ischemia. Additionally, although this study cannot show the effects of vaccination, this study is further proof of the mortality of the flu and strongly supports the continued effort of better hygeine/cohorting/vaccination of patients to try to prevent flu
2. TXA in epistaxis in patients taking antiplatelet drugs
– Decently large study of 384, RCT with reasonable inclusion criteria that is generalizable to many patients. Smart that they included only patients still bleeding after 20min of pressure as this is a much more conservative approach that is likely sufficient for many.
– Only patients on antiplatelet drugs, study reports excluding posterior epistaxis patients but in practice it may be difficult to determine who has a posterior vs anterior bleed.
– TXA showed benefits in stopping bleeding at 10min, as well as rebleeding in 24hrs and 1 wk. Discharge was also significantly quicker in TXA group. Complications (“nausea/vomiting or treatment intolerance”) rate trended towards TXA being worse but without statistical significance
– Good evidence for use of TXA in patients for quicker resolution of bleed and discharge, as well as added benefit of less future rebleeding. However, study was not large enough to capture complication rates of TXA, or complications outside of the 1 week window. Not surprisingly, patients much preferred plegets in their nose to anterior packing x3d. I would look forward to a similar study in non-antiplatelet patients.
a.) Strengths. Good data collection, given the access to what seems to be the complete care of these pts in the region. They identified and stratified by cardiac risk factors (although I would have liked to see more unconventional factors such as housing status).
b.) Limitations. Sample age was quite old (median 77yo). Overall this is a geriatric-seeming population who is well plugged into healthcare (a third received flu shots, most have diagnosed HTN/DM/HLD, etc). I worry about the generalizability of this demographic. furthermore, although they found a strong signal for influenza, they also found a signal for other respiratory viral infections…which may suggest the link is not just flu but rather pulmonary stress in general (which probably could be expected)
c.) primary outcome: increased incidence of MI following influenza infection in pts over 65yo
d.) Not particularly going to change my practice. Old people with flu, I would probably admit them regardless. Given this article, I might watch them closely for cardiac sx if I was on the inpatient team.
Zahed
a.) Strengths. Addresses a relatively common and frustrating chief complaint, with a simple intervention that is easily implemented in most EDs.
b.) Limitations. Neither the providers nor the pts were blinded to the treatment. It was a relatively small study (62 pts per treatment arm). The history of prior epistaxis (significantly higher in the TXA arm) represents a problem with randomization. They assessed 384 pts but excluded the majority of them (despite relatively straight forward exclusion criteria)…what was going on with enrollment?
c.) Primary Outcome. When pts (on anti platelet meds) are given TXA (vs nasal packing), epistaxis bleeding stops faster, there is less chance of rebleed in the coming week, faster time to discharge, and higher pt satisfaction.
d.) May change my practice. I will have to look into it further to see if we have topical TXA at BMC. I also want to read more about TXA in general.
Kwong et al.
.
Man! as if the flu didn’t suck enough!.
.
Keep in mind though, this is a retrospective study of only patients who were HOSPITALIZED in the control and risk interval. It’s conceivable, and probably likely from experience that many more who never sought care, were never tested for flu, or tested, treated (or not), and discharged did just fine. It already selected for a high risk population. Esp when you look at beginning of the results section, this population is SICK!. Median age was 77!
.
Zahed et al.
.
What a well conducted study that showed drastic differences. THere was no one lost to follow up! Only issue is that there’s no way to blind the patients or doctors.
.
Keep in mind they only looked at patients on antiplatelet drugs like ASA and clopidogrel. Unclear if the results would be applicable to patients on anticoagulation like warfarin.
.
Nevertheless, since it’s less painful, less invasive, more comfortable for the patient, and simply easier, there’s no reason not to try TXA first before you use nasal packing.
Kwong et al:
Agree with Alex. Another reason why the flu sucks. Usually, I err on the side of admitting elderly/baseline unhealthy patients with the flu, so this just adds to my argument. Now, though, I may add on a troponin or push harder for a timely EKG for these patients with flu + chest discomfort (and not chalk it up to coughing or malaise).
Zahed et al:
Great idea for a study. From what I recall, TXA is cheap and readily available, along with the other qualities Alex mentioned, so why not give it a try in the ED? No real harm.
Downsides: inability to blind the study, N is kind of low
For the Zahed article, yes completely agree that they would benefit from broadening the scope. I imagine that this will become standard of care once more research is done. Interestingly enough just after reading this I had an elderly woman come in with epistaxis, on elliquis. Even though it wasn’t quite the study population, I ordered TXA and Sara from pharmacy was fantastic about the prep, etc. The pt stopped bleeding on arrival and I didn’t get the chance to even use it, but I printed out the article and we had 3am journal club discussion in the middle of the B side. We ended up getting into a whole discussion of this article and then Ricky Kue’s morning teaching rounds on TXA in trauma as well
Kwong, et al.
1) Some strengths of the study include large population studied, and findings are supported by multiple prior studies, and common sense (people who have significant CV risk factors and get sick enough with the flu to go to the hospital are probably more likely to have AMI).
2) There are several confounding factors – most subjects who had an AMI during the risk period also were older (76% > 65 yo), 85% had HTN, 69% not vaccinated. Also the testing method for influenza/other resp viruses were varied, with various sensitivities/specificities.
3) They found an association between influenza infection and acute MI within 7 days of positive flu test, with an incidence ratio of 6. This was more prevalent in older patients infected with influenza B.
4) Not significantly. Any patient older than 65 with HTN, DM, HLD, coming in with symptomatic flu is likely to be admitted, and if they recover well after 1-2 days of observation, I wouldn’t see a reason to keep them in the hospital for 7 days just to make sure they don’t have an MI. It might be worthwhile to include MI symptoms in their discharge instructions as a return precaution. While this study didn’t look at the efficacy of the flu vaccine, I’d be much more likely to encourage my family members or patients who are older than 65 with CV risk factors to get their flu vaccine.
Zahed, et al.
1) Strengths: Well-designed study among a clinically relevant patient population.
2) Limitations: No blinding to the study participants, however they did blind the data analysts. Also, no way to definitively state severity of epistaxis, so its possible the nasal packing group had a disproportionately larger amount of more severe epistaxis pts (though unlikely given randomization).
3) Main outcomes: Topical TXA decreased time of epistaxis, ED LOS, and rebleeding occurrences at 1 day and 1 week after epistaxis in Pts taking antiplatelet agents. And not surprisingly, pt satisfaction was higher in the TXA group.
4) Yes please! Would love to try this prior to nasal packing since it seems to be more effective and more comfortable for the patient.
Kwong et al.
I agree with Alex, these are older sicker folks who had the unfortunate luck of developing an influenza infection. Many of them likely had bad hearts to begin with. I wonder how much we are simply measuring “demand” here (what we would call it in many other settings) leading to eventual MI? Also, the point that many, likely healthier people were probably discharged home or never came to the ED to begin with suggests that the “six times more likely to have an MI” may not be accurate.
Zahed et al.
This article won’t change my practice. I think TXA is great and don’t really understand why we don’t use it so often in the management of epistaxis at BMC. We used to soak rhino-rockets in the stuff before inserting them in Ireland. Works well. This study and others before it have confirmed this fact.
I don’t see how it wouldn’t be beneficial for posterior bleeds as well as long as you can deliver the medication to the source of the bleeding. The management of epistaxis has always seemed to bring out the Macgyver in all of us so why not use all the tools in the toolshed?
Kuong et al:
Strengths: The self-control period was long (1 year before and 1 year after the hospitalization for MI).
Limitations: A third seasonal variable could not be ruled out. Patients were excluded when timing of influenza couldn’t be established, and dates used were based on testing (influenza) and admission (AMI) rather than by symptom onset.
Outcomes: This study looked at the incidence of AMI within a 7 day period following laboratory diagnosis of influenza and other respiratory illnesses compared to incidence of AMI in all patients admitted with AMI within a 2 year period.
Practice changing: There is an infectious disease doctor, Mark Crislip, who does a bunch of ID podcasts, and I’ve heard him say many times over the years how infections (and inflammation in general) are pro-inflammatory states. This study supports that statement along with the previous research in this area. If anything, this article reminds me that influenza can be very dangerous for elderly patients and those with co-morbidities.
Zahed et al:
Strengths: ED-based study, 2 centers.
Limitations: Only looked at patients taking certain antiplatelet agents and for anterior nose bleeds. It was a relatively small study.
Outcomes: The primary outcome was bleeding cessation within 10 minutes and the secondary outcomes were rebleeding at 24 hours and 1 week, ED length of stay, and patient satisfaction.
Practice Changing: I agree with the previous commenters above that this article encourages me to use topical TXA more often. I haven’t seen a lot of epistaxis in the ED, but I would imagine that these results are generalizable beyond those on antiplatelet agent(s). The one time that I ordered topical TXA in the ICU for a nosebleed it hadn’t arrived within 1.5 hours and the bleeding had eventually stopped with direct pressure, so I cancelled the order without ever having given it.
Kwong
Retrospective chart review, 364 subjects
Median age 77, majority with CV risk factors
Outcome: incidence of admissions for acute myocardial infarction was six times as high during the 7 days of flu testing compared to control interval
Good to keep in mind for elderly pts with flu, PNA, lower threshold to EKG, Troy
Zahed
TXA vs anterior packing in epistaxis, will certainly incorporate this into my practice. I have done it at Lahey but not at BMC. Similar to the study used the IV formulation topically. Study used 500 mg in 5 mL. Study left the cotton ball in for only 10 min. I have done 20-30min. Improved pt satisfaction, decreased rates of rebleed, decreased LOS. Seems to be safe, no adverse reports noted. Likely little systemic absorption of TXA.