The throw-up throw-down

The Annals of Emergency Medicine published a study by April et al., that compared inhaled isopropyl alcohol to oral ondansetron for acute nausea. Although this isn't the first time isopropyl aromatherapy for nausea has been assessed; it is the best designed study, and assessed patients over a longer period than had been previously studied. This was a single center randomized, blinded placebo controlled trial that enrolled 122 nauseated adults who didn't require IV access into one of three arms:

1. inhaled isopropyl plus 4mg oral ondanseton 
2. inhaled isopropyl plus oral placebo 
3. inhaled saline plus 4 mg oral ondansetron 

A convenience sample of 208 patients with a presenting chief complaint of nausea or vomiting were screened for inclusion with 122 meeting inclusion/exclusion criteria.

• age > 18years
• presenting complaint of nausea or vomiting with a severity of 3/10 or greater

Exclusion criteria were:

• Isopropyl or ondansetron allergy
• inability to inhale through nose
• recent ingestion of medication contraindicated with alcohol
• altered mental status
• history of prolonged QTc
• suspected or known pregnancy
• patients who had IV access established
• Provider discretion

Reported nausea scores (0-100) were collected from patients at the 0, 10, 20, and 30 minute points. Initial nausea scores were similar across all three treatment arms. The findings noted a significant reduction in need for rescue antiemetic and patient reported nausea within both isopropyl aromatherapy arms; but not in the saline plus ondansetron arm.

This was a well designed study of emergency department patients who presented with a common emergency complaint, the clinical findings are impressive and are significant when considered in association with previous research on the topic. The results of this study alone should be interpreted with caution, however given that it was a single center trial with a small sample size. Additionally there was no discussion of statistical power, the confidence intervals were large and often crossed zero (although this could be due to an under-powered sample size), and that patients were often able to deduce which treatment they had received.

Despite the lack of statistical power this is a study that has the potential to change nursing practice: it suggests that isopropyl aromatherapy may be effective for a prolonged period, that it may show superiority to ondansetron and that it seems to be safe for people with mild to moderate nausea. This is a cheap easily executed therapy, one that doesn't require a prescription, it could be used effectively as a temporizing measure, or as an adjunct to other antiemetics. 


April, M. D., Oliver, J. J., Davis, W. T., Ong, D., Simon, E. M., Ng, P. C., & Hunter, C. J. (2018). Aromatherapy Versus Oral Ondansetron for Antiemetic Therapy Among Adult Emergency Department Patients: A Randomized Controlled Trial. Annals of emergency medicine.

Adult Oral Rehydration

The New England Journal of Medicine this month discussed a hospitals experience using an adult oral rehydration protocol in a large American metropolitan emergency department. This protocol was originally implemented as a result of IV fluid shortages. The protocol saw patients receive analgesia and antiemetics, as necessary, followed by directions to drink 30ml of the fluid of their choice every 3-5 minutes, 20 minutes after treatment.

Inclusion criteria were:

1. Acute Gastroenteritis
2. Hyperemesis Gravidum
3. Viral URTI/Pharyngitis

Exclusion Criteria were:

1. Moderate or severe dehydration
2. Contraindications to oral fluids (ex: bowel obstruction)

Reported outcomes:

1. 30% reduction in volume of IV fluids administered in the ED
2. 15% reduction in the number of physician orders for IV fluids. 

Unfortunately this protocol and accompanying data weren't published as a study, so there's limited baseline demographics, outcome measures, or comparison group information. They also unfortuantely didn't release patient specific measures such as satisfaction, need for rescue medication, or clinical outcomes - which limit the generalizability of this data.  

The hospital itself Brigham and Women's Hospital (one of the largest research hospitals in the world) may also suggest limits to the generalizability of this protocol (well funded tertiary centers); however, the practice is well established in pediatric patients (with a large systematic review) and is used in resource limited settings. 

This is a timely study, it addresses a current problem (IV fluid shortage); it also raises the question if IV fluids are superior to PO for mild dehydration, and what the impact of PO over IV rehydration strategies would have on patient satisfaction, care costs, length of stay and patient specific outcomes.

Patiño, A. M., Marsh, R. H., Nilles, E. J., Baugh, C. W., Rouhani, S. A., & Kayden, S. (2018). Facing the Shortage of IV Fluids—A Hospital-Based Oral Rehydration Strategy. New England Journal of Medicine.

Hartling, L., Bellemare, S., Wiebe, N., Russell, K. F., Klassen, T. P., & Craig, W. R. (2006). Oral versus intravenous rehydration for treating dehydration due to gastroenteritis in children. The Cochrane Library.

Weekly Review #20

A systematic review in the BMJ examined how well health professionals understand diagnostic tests. Using “statistics”, “healthcare”, and “accuracy” keywords the reviewers searched EMBASE, PsycINFO, and MEDLINE databases identifying 4818 hits. 74 were reviewed as potentially relevant based on title and abstract, with 28 meeting full inclusion criteria. Due to the heterogeneity of studies the systematic review was limited to presenting its findings in narrative format. The authors categorized the findings into four themes: self-rating, accuracy of definition, Bayesian reasoning, and presentation format categories. 

Two studies examined clinicians’ self-reported familiarity of statistical measures. In one study 13/50 clinicians reported understanding sensitivity, specificity, and positive predictive value; although only one was able to provide a correct definition when asked to do so. The other study found that only 58% of clinicians actually used statistical measures in their practice (although 82% claimed to do so). 

6 studies examined clinicians’ understanding of statistical definitions; they found that on average clinicians could provide a correct definition for sensitivity 76-88% of the time, specificity 80-88% of the time, but only 17% could correctly identify the correct definition for likelihood ratios.

22 studies examined how well clinicians’ were able to use pre-test probability and test accuracy to determine post-test probability (Bayesian reasoning). The studies found that in general clinicians had a poor understanding of Bayesian reasoning and were unable to determine post-test likelihood the majority of the time (0-61% success), clinicians also tended to overestimate post-test probability by 46-73%, and in one study clinicians inverted the likelihoods incorrectly interpreting patients with negative results as having a higher post-test likelihood of having a disease.

The 5 studies that examined presentation format found that healthcare providers were more accurate in their post-test estimates if the findings were expressed as natural frequencies (50 out of 100) rather than as probabilities (50%). The use of graphical aides improved clinician post-test accuracy to 73% compared to 48% when natural frequencies alone were used to communicated test power, or 23% when probabilistic language was used to describe tests.

This systematic review suggests that not only are we as healthcare providers poor at using probabilistic reasoning; but that we’re also oblivious to our weakness in this area. As a nurse I know that the preparation I received in school to interpret and use statistics was severely lacking. This research, which focused primarily on physicians, would suggest that this is a common area of weakness. This research highlights how little we all know about the tools we use on a daily basis, it may also shed some light on why so few of our colleagues engage with research, and I would suggest that most importantly it empirically shows that we could all use some brushing up on how to use statistics. I’ve covered some great resources to help with this is a few previous weekly reviews (#4 & #6) and would suggest that anyone looking for a brief intro into using Bayesian statistics take a look at the first few chapters of this online book. 

http://www.ncbi.nlm.nih.gov/pubmed/26220870

Steve Mathieu reviewed the HEAT trial of acetaminophen for fever in critically ill patients on The Bottom Line Review. This study was a double blind RCT of 700 patients that sought to determine if the administration of paracetamol to critically ill patients had any effect on: ICU free days, mortality, length of stay (LOS), number of days on organ support, and its effect on lab values and temperature. Patients were block randomized to receive either 1g IV paracetamol, or IV D5W every 6hrs for 28 days or until: ICU discharge, fever resolution, cessation of antibiotics, death, or contraindication. The study found no statistical difference in mortality, LOS, ICU free days, or organ support, although patients who received paracetamol had a lower (0.25C) average temperature. This research is contrary to a retrospective study published earlier this year that found a mortality benefit associated with paracetamol administration, it has a much higher quality design, and is one that I've been waiting to see published. Mathieu's summary of this research is concise, easy to interpret, and very timely; the summaries on this site are consistently of very high quality, this review and the site in general are a fantastic resource.

http://www.wessexics.com/The_Bottom_Line/Review/index.php?id=7257804966227311886

A retrospective analysis of tourniquet use in the pre-hospital setting was published in the Journal of Acute Care Surgery this month. Ode et al., examined the EMS use of tourniquets in a metro North Carolina ambulance service during 2012-2013. They examined patients with uncontrolled hemorrhage to determine the frequency of “correct” tourniquet (Tk) application, the efficacy of Tk as a treatment, and the frequency of Tk related adverse outcomes. 98 patients met the inclusion criteria (uncontrolled hemorrhage), 42 were excluded because they were treated outside of the metro area. Of the remaining 56 patient: 24 received a Tk (19 Combat Application Tourniquet, 5 improvised), although 5 were deemed unnecessary (the patients weren’t in shock - SBP>80mmHg) and 4 were delayed. Of the 32 who didn’t receive tourniquets three were indicated, but did not receive treatment.

The patients treated with a Tk, compared to those not, had significantly higher rates of: shock (50 vs 12.5%), vascular injury (69.6 vs 25.8%), blood transfusion (37.5 vs 9.4%), rates of admission (77.3 vs 38.7%), and mortality (8.3 vs 3.1%). None of these findings are surprising given that the protocol for application of a Tk was quiet conservative, requiring patients to be in shock, and therefore significantly sicker. Secondary analyses showed that patients who were indicated to receive a Tk but didn’t had higher incidence of shock compared to those who did (85.7 vs 60%), and that those who weren’t indicated (not in shock) but did receive a treatment by tourniquet had no adverse outcome as a result.

Due to the overly conservative treatment protocols, the small sample size, and the lack of an equivalent control arm the primary results of this study have little to contribute to the overall body of evidence for Tk use in civilian trauma. The secondary analysis does show worse outcomes for patients with missed Tk’s, and no complications associated with liberal Tk (non-indicated) use; although the numbers (n=22) are too small to reach statistical significance. From a clinical perspective this research would seem, in a small way, to support that liberal Tk use isn’t associated with worse outcomes, and that even extremely conservative (only once shock becomes apparent) Tk use imparts benefit. From a practical perspective this research provides weak evidence to support Tk use in civilian trauma, it also suggests that the current military research may be generalizable to the civilian population, and indirectly it would seem to suggest the need for a liberalization of Tk protocols among EMS services. 

http://www.ncbi.nlm.nih.gov/pubmed/26402532

Using the current VW emission scandal as a comparison piece Richard Smith offered a critique of scientific misconduct on his BMJ blog, and suggests that scientists should face criminal charges if found guilty. Criminal charges have been used to punish scientific misconduct before, as was the case with June Dong-Pyou Hon’s faking of HIV immunization results; and Smith offers three additional reasons why misconduct should be investigated criminally: Because inappropriate use of research funding is financial fraud, because universities are poorly equipped to conduct investigations, and because investigations by the university would be a conflict of interest. I would also suggest that there is a basis for criminal charge based on harm to the patient, for example the intentional non-disclosure of the increased risk for suicide when paroxetine is used to treat pediatric depression, and Andrew Wakefield's fabrication of evidence that immunizations result in autism. A thoughtful and timely piece by Smith, maybe one that will find increased traction.

http://blogs.bmj.com/bmj/2015/09/28/richard-smith-if-volkswagen-staff-can-be-criminally-charged-so-should-fraudulent-scientists/?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+bmj%2Fblogs+%28Latest+BMJ+blogs%29&g=w_blogs_bmj-com

On the Trauma Professionals Blog Micheal McGonigal discusses the reflexive way that many clinicians treat low oxygen saturation readings. He discusses factors that can result in artificially low reading, patient groups where a low reading is normal, the absence of a good definition of "normal values", and suggests that if the patient is not distressed on examination they likely don't need supplemental oxygen. This is a quick reminder to treat the patient and not the number.

Mark Culver discussed the differences between intermittent and continuous PPI therapy for UGIB on Emergency Medicine PharmD. There has been a fair bit of research into this topic lately, and UpToDate had suggested changing practice from continuous to intermittent PPI therapy last year; however the practice remains widespread. This post offers a great review of the research behind the change in recommendations. The cost savings, and reduction in nurse time this practice change could result in make this post well worth the read.

There was a podcast review of fluid resuscitation in hemorrhagic shock on HEFTEMCAST. This podcast reviews the key evidence and discusses the concepts of: damage control resuscitation: permissive hypotension, hemostatic resuscitation, and damage control surgery. The review includes seminal work from the military as well as evidence from civilian trauma, it nicely summarizes the key literature, and provides links to the source research. This 16 minute review is well worth a review for anyone working in an emergency settings.

Josh Farkas offered a well balanced review of the SPLIT trial on PulmCrit. The SPLIT trial examined the differences between PlasmaLyte and Saline in patients admitted to the ICU, and found that there was no significant difference between the two fluids. Farkas acknowledges that the findings are valid among the patients reviewed, but critiques the external validity of the study; he points out that the small volumes of fluid received, the admission reason (elective post-operative), and the low illness severity observed among the patients in this cohort are not generalizable to the typical ICU population.

Activated Charcoal

Activated charcoal is the most commonly used treatment in patients with poisoning (Lai et al., 2006). It may be used for a variety of poisonings, except with corrosives, iron, lithium, arsenic, and alcohols, for which AC is unable to bind (Olson 2010).

Activated charcoal (AC) is a porous carbon product, with a large surface area for binding with drugs, chemicals, and organic compounds. This binding or "adsorption" is useful in the clinical context because when ingested it bind with toxins preventing gastric absorption. The AC bound chemicals are then excreted in feces.

There is debate about the efficacy of AC in toxicities. To date there hasn't been any high quality evidence linking morbidity or mortality improvements with the use of AC (Chyka et al., 2004). The evidence that is available comes from: small non-blinded trials, case reports, animal studies and trials performed on volunteers (some of which are RCT's) that examined serum toxicity levels as corrolary for clinical measures (Olson, 2010). Regardless of the lack of clear clinical benefit AC is widely used  as a first line treatment of toxic ingestion because it is relatively safe, has a has been shown to lower serum drug levels, and is widely endorsed as by professional groups and organizations.

Most current recommendations are that AC may reduce toxin absorption if administered within 1 hour of poison ingestion (although it can be administered later), that AC should not be used in patients who cannot maintain their own airway, because of the risk for AC aspiration and resultant pneumonitis (Chyka et al., 2004), and that AC should also not be given to patients with, or at risk for, GI perforation as it will obscure endoscopic investigation of the stomach (Chyka et al., 2004). Indeed in many patients it may be safer, and more effective to use specific antidotes ex: mucomyst (Olson 2010). Regional practice may also be guided by specific institutional policies which may vary from these guidelines.



Activated charcoal dosing is usually 0.5-1g/kg in pediatric populations. For adults there is typically an initial dose of 50-100g, which may be followed with 50g every 4 hours (which may be divided) (Chyka et al., 2004). If activated charcoal is administered by nasogastric (NG) tube it is essential to ensure correct tube placement, for the same reason that AC should not be given to patients unable to maintain their own airways, because it can cause severe chemical pneumonitis (Bond 2002). Because NG insertion can also be traumatic, painful, and poorly tolerated, most patients will be given AC orally. Most patients will tolerate AC orally; however palatability can be a major barrier, especially in the pediatric populations.

A number of studies have sought ways to improve and measure the palatability of AC, the majority have used readily accessible mixes such as juice, milk or cola. Most of these studies have examined pediatric populations and the effects of mixes have on flavor and ease swallowing the AC mixture: Cola  has consistently been selected as the preferred mix for AC in pediatric populations in terms of flavor, ease of swallowing, and overall preference (Dagnone et al, 2002., Skokan et al, 2001). Unfortunately there hasn't been much in the way of similar research among adult patients.

Anecdotally I have seen a huge difference in compliance of AC administration when mixed with cola in both the pediatric and adult populations. For children there is an improvement in flavor, the fizz is fun, and the color of the cola doesn't change with the addition of AC, for adults there is less of a chance that allergies or aversions to dairy will present a barrier of using it as a mixture. From a pragmatism perspective cola is a clear winner as it's shelf stable, and readily available wherever there is a vending machine.




Bond, G. R. (2002). The role of activated charcoal and gastric emptying in gastrointestinal decontamination: a state-of-the-art review. Annals of emergency medicine, 39(3), 273-286.

Chyka, P. A., Seger, D., Krenzelok, E. P., & Vale, J. A. (2004). Position paper: Single-dose activated charcoal. Clinical toxicology (Philadelphia, Pa.), 43(2), 61-87.

Dagnone, D., Matsui, D., & Rieder, M. J. (2002). Assessment of the palatability of vehicles for activated charcoal in pediatric volunteers. Pediatric emergency care, 18(1), 19-21.

Lai, M. W., Klein-Schwartz, W., Rodgers, G. C., Abrams, J. Y., Haber, D. A., Bronstein, A. C., & Wruk, K. M. (2006). annual report of the American Association of Poison Control Centers toxic exposure surveillance system.Clinical Toxicology, 44(6-7), 803-932.

Olson, K. R. (2010). Activated charcoal for acute poisoning: One toxicologist’s journey. Journal of medical toxicology, 6(2), 190-198.

Skokan, E. G., Junkins, E. P., Corneli, H. M., & Schunk, J. E. (2001). Taste test: children rate flavoring agents used with activated charcoal. Archives of pediatrics & adolescent medicine, 155(6), 683-686.

Weekly Review #5

A group of Chinese researchers compared silver sulfadiazine (Flamazine) to Mepilex Ag for treatment of deep partial thickness burns. This was a multi-center, open, parallel, randomized comparative study of patients with thermal burns to 2.5-25% TBSA (<10% TBSA third degree). Exclusion criteria were burns >36hrs from enrollment, infection, skin disorders, certain medical and immunological conditions, and immunomodulating medications. Primary outcome measure was time to healing; secondary measures were: percentage burn healed per visit, number of dressing changes, and number of burns requiring grafting. Nurse investigators performed debridement on day zero and as required, assessed wounds, performed dressing changes, while noting ease of dressing change and wound-dressing adherence. Patients in the Mepilex Ag had dressing change every 5-7 days depending on need, patients with SSD dressing had daily dressing changes. Patients were asked to report on anxiety of dressing change, pain of dressing change, and comfort of dressing during daily living.  153 patient met inclusion criteria 46% were assigned to Mepilex Ag. Average patient age was 36.2 yrs, 27% were female, all were Asian, all other baseline characteristics between the groups were similar. Between the two groups: healing times 16.2 (Mepilaex Ag) vs 17.0 days (SSD), and rates of successful healing (79%) were similar, additionally there was no difference in graft rates or total burn area healed by the ends of weeks 3-4. Mepilex Ag had higher patient satisfaction for comfort, anxiety, and pain of dressing change with pain and anxiety scores tending to be about half of the SSD group scores. There were fewer dressing changes required in the Mepilex Ag arm, and higher ratings by nurses for ease of application. There were more patients in the Mepilex Ag arm healed by week 2 (day 7), more patients in the SSD group who developed new infection of the burn (9 vs 6%), and more patients in the Mepilex Ag arm who required subsequent wound debridement: although this is likely due to lower rates of wound-dressing adhesion . These findings support previous studies of similar design, and suggest that there may be an opportunity for cost savings due to decreased material and labour costs. From a nursing perspective this research suggests that following standard practice of Flamazine and non-stick dressing, may not be to the benefit of the patient, provider or health care system.
http://journals.lww.com/jtrauma/Abstract/2015/05000/An_open,_parallel,_randomized,_comparative,.16.asp

Ian Miller from the Nurse Path posted a link on his twitter feed this week to NPS MedicineWise Education modules. These are free continuing education modules designed for physicians, pharmacists, and nurses. There is a broad selection of modules: case studies, medication reviews, laboratory test reviews, even modules on how to improve charting. These modules will count toward continuing education credits among Australian professional bodies, and offer free access to education materials for clinicians from other countries, worth a look. 
http://www.nps.org.au/health-professionals/cpd/nurses

I was doing some research on triage and came across a 2012 article published in the Journal of Internal and Emergency Medicine that looked interesting. It was a before/after single center intervention to determine if a physician in triage would increase ED patient throughput. Secondary measures were length of stay, time to attending physician assessment, time to disposition, number of patient who left without being seen, and time on ambulance diversion. ED patient encounters during the 3 months preceding the intervention were retrieved from an electronic record database, and used as the control arm. During the study period one additional physician was added to triage, and one RN and ED technician were reassigned from other areas within the ED to the physician triage team daily from the hours of 1300-2100 for three months. This triage team would then order labs and diagnostics, administer medication, fluids and other treatments, after which the patient would move to another area of the department to be assessed by the attending physician. The physician in triage (PIT) would also supervise the physician assistant (PA) in the fast-track area, answer calls from referring physicians, and engage in administrative roles when not engaged in triage activities; the authors didn't specify what the RN or ED technician did during these periods. During the study period 17,631 patients met the inclusion criteria, 9,218 in the intervention group. The PIT evaluated an average of 37.8 patients per 8-hour period (15.1 seen and discharged with the PA, 4.9 seen and discharged as sole provider in fast-track, and 17.8 triaged to be seen by another attending physician). During the intervention period time to assessment by attending was reduced by 36 minutes (1:41-1:05); Length of stay (LOS) was reduced by 12 minutes (3:51-3:39). LOS and time to assessment were also decreased during the study period during the times the PIT was not present. The percentage of patients who left without being seen saw an insignificant decrease (1.47-1.33%), and the time spent on diversion decreased significantly during the intervention period (3.1-1.2%). While a PIT model is exciting there are a few shortcomings in this research: the intervention was the addition of a staff physician for 8 hrs a day (two full time physicians per year). Because there was an addition of extra staff there's little surprise that time measures were decreased, what wasn't assessed however was if there was any change in clinical outcomes. Unfortunately this study design doesn't provide any insight into what part of the intervention resulted in increased throughput: was it more staffing, faster initiation of diagnostics, or an integrated model of Physician/RN/ED Technician that resulted in faster access to care. From a nursing perspective this is exciting research, but it fails to reveal what the true cause of increased ED throughput was, and if it was clinically significant.
http://link.springer.com/article/10.1007%2Fs11739-012-0839-0

Charlotte Davis from Paediatric Emergency Medicine put together a nice blog post on functional pediatric abdominal pain. Functional abdominal pain (pain with no identifiable medical cause), she suggests, could be responsible for as much as 25% of pediatric abdominal pain Davies has a a brief write up on some possible causes for this type of pain: duodenal ulcer, irritable bowel syndrome, and abdominal migraines. She also offers some suggestions for clinical work-ups,  and red-flag findings. From a nursing perspective there is some insight to be gained from causes of pediatric abdominal pain, the red-flag findings may also be helpful for stratifying risk with pediatric populations during care or triage. 
http://paediatricem.blogspot.ca/2015/06/functional-abdominal-pain.html

BioMed Research International (a free open access journal) published some research on the effects of IV fluid volumes on mortality. The study by Hussmann et al., was a retrospective examination of the relationship between pre-hospital IV fluid replacement and mortality of patients from a German trauma registry. 7461 patients met inclusion criteria (admitted patients, age ≥16, ISS ≥16), and were cohorted into 5 groups according to total pre-hospital IV fluid received: (0-500mL, 501-1000mL. 1001-1500mL, 1501-2000mL, >2000mL). Multivariate mortality analyses were performed by: volume replacement, age, trauma score, type of trauma, pre-hospital interventions (chest tube/ETT insertion, pressor usage), and lab parameters (HgB, BE, PTT). They determined that there was a correlation between volume of fluid administered and overall mortality. However there are some aspects of the design and statistical findings that may limit it's usefulness to practice. All of the patients in this study were physician attended pre-hospital, which does not generalize to all EMS systems. As volume of fluids administered increased so too did injury severity, number of interventions performed and injury severity. It it likely that IV fluid administration not the causal factor in this correlation; rather, as severity of injury increased so too did the number of interventions performed, the time required to perform these interventions would increase, and therefore the period of time in which to administer fluid would increase, hence an increase in overall volume. Likely injury severity is causal factor in the outcome/ volume administered relationship. Unfortunately there are no The findings are hard to interpret as there was no specifics on average total volume administered per volume quintile, so it's possible that the majority of patients where clustered around cut-off points. Finally the statistical findings are not terribly convincing, as the majority of the confidence intervals for mortality odds ratios cross one in the general population. It is only the post hoc analysis for non-head injured patients that there is any statistical significance of increased risk associated with volume; however this may still not be clinically significant as it is more likely a result of increase in injury severity and patient acuity than an independent risk factor. From a nursing perspective this research has little to add, although the results are of questionable use it is a reminder that IV fluids should not be considered benign. 
https://www.readbyqxmd.com/read/25949995/prehospital-volume-therapy-as-an-independent-risk-factor-after-trauma#.VV4fMVQNHz0.mailto