Boring Question: How useful are plain abdominal films for bowel obstruction?

Clinical Scenario

An otherwise healthy 65 year old comes into the emergency department with an 8 hour history of abdominal pain. Her last bowel movement was 3 days ago and she’s not sure if she has passed gas.  She endorses nausea but has not vomited. She has not taken her temperature but does not believe she has been febrile. She’s tried Tylenol for analgesia with little relief. She last ate 12 hours ago and has recently only prepared home cooked meals with no new foods. Her urination has been normal. She has had a number of surgeries including a hysterectomy (1990) and cholecystectomy (1995). There is no family history of colon cancer and she had a normal screening colonoscopy two years ago after an episode of rectal bleeding.

On physical examination, her vital signs were:

Temp: 37.6, HR of 90, RR:18, BP:128/80, O2: 99% on room air.

On exam, she looks uncomfortable moving around on the stretcher. Her abdomen looks slightly distended, you didn’t auscultate her bowel sounds (see why here) and she has diffuse tenderness of the abdomen but no peritoneal signs. She does not have flank percussion tenderness. The rest of her exam is unremarkable. You wonder:


Boring Question:  How useful are plain abdominal films for a patient with abdominal pain and suspected small bowel obstruction?


Radiographs are also ordered in the emergency department for patients with acute abdominal pain. Flat and upright abdominal films, upright chest films and lateral decubitus views can be used to screen for bowel obstruction, constipation or free air (1). Plain abdominal films may demonstrate air fluid levels which may suggest mechanical obstruction. While these levels may suggest an obstruction, they are not pathognomic for such a condition (2). Plain abdominal x-rays also expose patients to about 35 times the radiation as a dose of a chest x-ray (3).

Search Strategy

Using PubMed, three separate searches were performed. These were:

1. “abdominal radiographs” AND “small bowel obstruction”

2. “plain radiographs AND “abdominal pain”

3. “abdominal x rays” AND “acute abdominal pain” AND “emergency department”

The resulting article titles and abstracts were screened with relevant articles reviewed. In addition, the textbook ‘Tintinalli’s Emergency Medicine’ was used. For investigations highlighted in review literature, the primary studies were assessed.

The Evidence

Taylor et al published a scientific article in 2013 that identified five studies, attempting to assess the usefulness of plain radiographs in diagnosing small bowel obstruction (4). Three of these investigations were prospective case studies with two retrospective case studies. All these investigations used the criteria of SBO on x-ray to be two or more air fluid levels in dilated loops of bowel (more than 2.5 cm) (4). The positive likelihood ratio was published to be 1.64 as the collective for these investigations.

A study by Van Randen et al in 2011 discussed a multi-center trial for patients with abdominal pain lasting between 2 hours and 5 days (2). Each patient was clinically assessed with physical examination and laboratory blood work, with subsequent supine abdominal and upright chest x-rays (2). This investigation found a positive predictive value of 54% for patients with a bowel obstruction with the clinical assessment and 61% after radiographs (2).

In the late 1990s, Suri et al conducted a small prospective study, comparing abdominal x-rays with ultrasound and CT to diagnose small bowel obstructions (3, 5). The calculated positive likelihood ratio from their findings is 1.54. Maglinte et al in 1996 also attempted to assess the value of CT and abdominal radiographs in patients with suspected small bowel obstruction (3, 6). For abdominal films, the positive likelihood ratio can be calculated to be 1.60 from their findings.

Bottom Line

From the literature assessed, plain abdominal films and chest radiographs have limited added diagnostic value for patients with abdominal pain and suspected small bowel obstruction.



Review by an Attending

Patients suspected of bowel obstruction are a heterogeneous group and include patients that may have ileus, gastroparesis or gastroenteritis. The gas pattern also varies due to severity, level and duration of the obstruction. It should be no surprise, therefore, that the radiographs can be normal in 1/3 of cases [especially in the setting of partial obstructions]. That said, many of these patients could be treated conservatively with 40-75% resolution.

Radiologists look at more than just the presence [and number] of air-fluid levels and dilated loops of bowel –for example “mean differential air-fluid levels”. Most studies use rad-reads in patients known to have bowel obstruction. So the published test characteristics reflect the best possible scenario. So I believe that an emergency-read plain film will probably perform even less favorably than you have described.

However, plain films may still have a role depending on factors such as resource availability. I would be reluctant to advocate for CT-everybody approach given the risk of radiation and the current global trend of spiraling health costs and ED overcrowding. It appears that ultrasound may now also emerging as a potential alternative to CT. I would advocate for a sit-down between EM, surgery and radiology to derive an algorithmic approach to which modality would best serve patient needs in your center.

- Nadim Lalani  MD FRCPC



1. Tintinalli’s Emergency Medicine-A Comprehensive Study Guide (2011). New York. McGraw Hill Companies Inc

2. Van Randen A, Lameris W, Luitse JSK, Gorzeman M, Hesselink EJ et al. (2011). The role of plain radiographs in patients with acute abdominal pain at the ED. The American Journal of Emergency Medicine. 29 (6). 582-589.

3. Smith JE, Hall EJ. (2009) The use of plain abdominal x rays in the emergency department. Emergency Medicine Journal. 26(3).160-3.

4. Taylor MR, Lalani N. (2013). Adult Small Bowel Obstruction. Academic Emergency Medicine. 20(6). 528-544.

5. Suri S, Gupta S, Sudhakar PJ et al. (1999) Comparative evaluation of plain films, ultrasound and CT in the diagnosis of intestinal obstruction. Acta Radiol 40(4). 422-8.

6. Maglinte DD, Reyes BL, Harmon BH et al (1996). Reliability and role of plain film radiography and CT in the diagnosis of small-bowel obstruction. AJR Am J Roentgenol 167(6). 1451-5.


Author information

Eve Purdy
Medical Student Editor at BoringEM
Fourth year medical student at Queen's University-happily consuming, sharing, creating and researching #FOAMed

The post Boring Question: How useful are plain abdominal films for bowel obstruction? appeared first on BoringEM and was written by Eve Purdy.

Ondansetron vs Placebo vs Metoclopramide: Normal saline as an antiemetic?

This week we review an article comparing ondasetron, metoclopramide and placebo (normal saline).

Title: Antiemetic use for nausea and vomiting in adult emergency department patients: randomized controlled trial comparing ondansetron, metoclopramide, and placebo. PMID: 24818542


Why is this paper important?

Nausea and/or vomiting are common emergency department (ED) presentations. While investigating underlying cause and establishing a diagnosis are important, so too is the goal of relieving the patient’s symptoms. This paper evaluates two commonly prescribed anti-emetic medications and placebo in a head-to-head comparison for the treatment of ED patients with nausea and/or vomiting.

Catching Up

The success of pharmacologic anti-emetic strategies in oncology and post-operative patients (1, 2) was extrapolated to support use in patients with un-differentiated nausea and vomiting in the ED. Four studies (3, 4, 5, 6) have shown success of metoclopramide and/or ondansetron in reducing the severity of nausea in the ED, but the only two placebo controlled studies showed no benefit of these medications over placebo (3, 4). Severity of nausea and vomiting is frequently measured using a visual analogue scale (VAS) and a minimally significant change has previously been defined as 15mm (7). This topic was previously covered by Ryan Radecki in a post “Nausea? We’ve got placebo for that” on EM Literature of Note.

The Study: Ondansetron vs Placebo vs Metoclopramide

Bottom Line

IV ondansetron and metoclopramide are no better than placebo at improving patient perceptions of nausea and vomiting along a visual analogue scale but all three provide a clinically significant improvement in symptoms.

The PICO Question

Population: Adult patients with nausea and vomiting during ED care for which the physician prescribed IV anti emetics.

  • Exclusions: hemodynamic instability, critical intervention needed, pregnancy or lactation, Parkinson’s disease, restless leg syndrome, use of antemtic in last 8 hours, previous IV fluids during ED stay, N/V related to vertigo/chemo/radiotherapy, previous allergy to a study medication


  • Metoclopramide 20mg IV (10mg/2ml x 2-2ml syringes)
  • Ondansetron 4mg IV (4mg/2ml x 1-2ml syringe + 0.9% saline x 1-2ml syringe )


  • 0.9% Saline 4ml (0.9% saline x 2-2ml syringes)


  • Primary: mean change in severity rating on the VAS 30 minutes after administration of study drug
  • Secondary: 
    • Median change in severity on the numeric rating scale
    • Adjectival description of change
    • Change in number of vomiting episodes
    • Need for rescue medication
    • Patient satisfaction
    • Adverse Events

Of 744 patients screened, 385 were eligible for enrollment (see exclusion criteria above) and 270 underwent randomization. Data on 258 patients (96%) was available for analysis. The results after 30 minutes were:

  • Less need for rescue medication in the metoclopramide group (18%) compared to ondansetron (35%) and placebo (36%). No statistically significant differences in the other secondary outcomes.
  • Nine adverse events were reported (3.5%) with six were in the metoclopramide group. Of those, two had akathisia, two had restlessness, one had muscle twitching, and one was diaphoretic. There were also two minor adverse events with ondansetron and one with placebo.


Internal Validity

This study met most of the criteria for high internal validity:

  • Randomisation was centralized and computer generated.
  • Treatment groups were similar at baseline on important factors such as gender, age, clinical cause, number of vomiting episodes and initial VAS score.
  • Patients, care-givers and data collectors were blinded to the intervention through rather elaborate measures to conceal delivered medications. In this case, blinding was particularly important because all other factors of treatment were not perfectly controlled. Physicians were free to implement treatments other than antiemetics at their discretion. We have no data on whether opioids/steroids/other medications were given differently to each group. Since there is no guarantee in the protocol that groups remained similar throughout ED stay, we are left to hope that proper blinding prevented against any systematic confounding bias towards or against a specific treatment.
  • Follow-up was near complete (96%). The 4% lost to follow-up were excluded but the remaining were included analyzed using the intention-to-treat principle. Ideally it would have been nice to see a “best and worse” case scenario analysis with the missing results, but it is still unlikely that this small missing cohort would change the conclusion.
  • The study endpoint was symptoms at 30 minutes, however, nausea often comes in waves rather than being a persistent phenomenon. As such, it would have been helpful to see comparison at a number of different evaluation time points (ie. 60 minutes, 120 minutes) to account for more realistic symptomatology and provide information that may be relevant when considering patient discharge.
External Validity

After confirming that a study internally valid it is important to think about whether or not the results are generalizable. This study is generalizable with a few considerations to keep in mind when applying to your patients.

  • First, the exclusion criteria eliminate (with good reason) a significant number of patients with nausea and vomiting. Before you think about applying the results of this study by skipping on IV anti-emetics make sure that the patient does not meet one of these exclusion criteria.
  • Second, the dosing of medications must also be considered. The recommended dose of ondansetron is 0.15mg/kg so it could be argued that patients were actually underdosed in this trial by receiving 4mg. Conversely, metoclopramide is most often dosed at 10mg (rather than 20mg) so the increased number of side effects may have been attributable to that.
  • Unfortunately this trial did not include anti-emetics delivered PO, IM or SL. We often administer medications this way to avoid an IV. We can’t extrapolate the results from this study for those alternate antiemetic strategies.


So What?

Is normal saline the new ondansetron? This study demonstrates that there was no difference between IV anti-emetics (ondansetron and metoclopromide) and an IV placebo of 0.9% saline in the reduction of undifferentiated nausea &/or vomiting in a convenience sample of ED patients. Given the possible adverse effects and costs associated with antiemetics, should we re-evaluate their role in this patient population? Or is this another study that will not be replicated?

The not so boring question

If it does turn out that ondansetron is no better than placebo,should doctors be able to prescribe a placebo medication? Is it unethical if it works? Why? Why not? What do you think the results would have been for a fourth group with no intervention? Or perhaps the 4ml of 0.9% saline is not actually a placebo. After all, we know normal saline isn’t so normal after all.

Please comment below.

This post was reviewed by Dr. Andrew Petrosoniak (@petrosoniak).


1. Carlisle J., & Stevenson C. (2006). Drugs for preventing post operative nausea and vomiting. Cochrane Anesthesia Group. Accessed online:;jsessionid=55EBBAA09E9A3009F704B0C0A22FC995.f01t04

2. Billio A., Morello E., & Clarke M. (2009). Serotonin receptor antagonists for highly emaetogenic chemotherapy in adults. Cochrane Pain, Palliative and Supportive Care Group. Accesed online:

3. Braude, D., Soliz, T., Crandall, C., Hendey, G., Andrews, J., & Weichenthal, L. (2006). Antiemetics in the ED: a randomized controlled trial comparing 3 common agents. The American journal of emergency medicine, 24(2), 177-182.

4. Barrett, T. W., DiPersio, D. M., Jenkins, C. A., Jack, M., McCoin, N. S., Storrow, A. B., … & Slovis, C. M. (2011). A randomized, placebo-controlled trial of ondansetron, metoclopramide, and promethazine in adults. The American journal of emergency medicine, 29(3), 247-255.

5. Braude, D., & Crandall, C. (2008). Ondansetron versus Promethazine to Treat Acute Undifferentiated Nausea in the Emergency Department: A Randomized, Double‐blind, Noninferiority Trial. Academic Emergency Medicine, 15(3), 209-215.

6. Chae, J., McD Taylor, D., & Frauman, A. G. (2011). Tropisetron versus metoclopramide for the treatment of nausea and vomiting in the emergency department: A randomized, double‐blinded, clinical trial. Emergency Medicine Australasia, 23(5), 554-561.

Author information

Eve Purdy
Medical Student Editor at BoringEM
Fourth year medical student at Queen's University-happily consuming, sharing, creating and researching #FOAMed

The post Ondansetron vs Placebo vs Metoclopramide: Normal saline as an antiemetic? appeared first on BoringEM and was written by Eve Purdy.

Boring Question: How does the sensitivity/specificity of lung ultrasound compare to plain films in diagnosing pneumothorax?

The Case

A 74-year-old male with a history of COPD arrived in the emergency department in respiratory distress. On physical examination, the patient was mildly tachypneic and had an oxygen saturation of 93% on a non-rebreather mask. On auscultation, the patient had wheezing and diminished air movement bilaterally. A supine chest radiograph (CXR) was obtained. A short time later, a radiologist called to confirm the presence of a “moderate sized right pneumothorax” (Figure 1).

Figure 1 - Chest X-ray initially read as a right pneumothorax.

Figure 1 – Chest X-ray initially read as a right pneumothorax.

As a chest tube tray was being prepared, a bedside ultrasound (US) was performed and showed bilateral lung sliding. (Link to Case Video or simply see below.)


The Question

Is lung US more or less sensitive and specific than CXR in diagnosing pneumothorax?

The Answer

Whereas our patient presented with a pneumothorax (PTX) presumably due to COPD, most of the evidence for the sonographic diagnosis of PTX is based in the trauma literature. Four recent meta-analyses have addressed the use of sonography for PTX, and all support ultrasound as vastly superior to supine CXR as evidenced by their sensitivities for diagnosing PTX. For all the included studies, the sensitivity of US and CXR for PTX detection ranged from 78.6-98% and 28-75%, respectively.

Name Year N # of publications included U/S sens CXR sens US spec CXR spec
Wilkerson 2010 606 4 86-98% 28-75% 97-100% 100%
Ding 2011 7569 20 89% 52% 99% 100%
Alrajhi 2012 1048 8 90.9% 50.2% 98.4% 99.4%
Alrajab 2013 1514 13 78.6% 39.8% 98.4% 99.3%


Of note, most patients included in these meta-analyses were trauma patients that underwent supine imaging; it is difficult to judge whether the characteristics of CXR might have improved accuracy if imaging were done in the upright or lateral decubitus positions [4,5]. The gold standard for diagnosis of PTX in each of these meta-analyses was demonstrated PTX on CT scan or a rush of air with chest tube insertion.

The Test

Now that we know US is more sensitive and specific than CXR in diagnosing PTX, how do we perform the test? The authors of a recent publication found that in supine patients, most pneumothoraces were located beneath the 5-8 intercostal spaces [7], which makes that the best place to start scanning. The most commonly taught sign of PTX on lung US is the absence of lung sliding.


In lung sliding, the visceral-parietal pleural interface (VPPI) appears as a hyperechoic (white) line beneath the cross-sectional cut of the ribs and moves back and forth with respiration. In PTX, this white line will not move with respiration. Recall that the patient in our vignette had bilateral lung sliding despite a CXR that showed moderate right sided PTX’. [Video 2: Moderate Pneumothorax]


The presence of lung sliding effectively rules out a PTX, but its absence does not necessarily rule one in (Figure 2), so correlating your sonographic findings with the clinical exam is important.

Figure 2 - Causes of no lung sliding.

Figure 2 – Causes of no lung sliding.


If you don’t see lung sliding, the presence of comet tails or b-lines can be used to help rule out a PTX, since these artifacts originate from the visceral pleura [8]. [Video 3:  B-lines with no lung sliding.]


One sign thought highly specific for PTX is the lung point. This represents the limit of the PTX and is identified when both lung sliding and the absence of lung sliding are seen in one area. If this is present you will see the hyperechoic (white) pleural line sliding normally and right next to it an area that is not sliding within the same intercostal space.  [Video 4:  Lung point]


You can see a more detailed description of one here). Some physicians use m-mode in diagnosing PTX by US, but m-mode really has no role unless you need to print out a still image proving a PTX. A recent publication found that using m-mode decreases accuracy in diagnosing PTX versus using b-mode (i.e., normal US mode)[1].

The Bottom Line

When evaluating a patient with respiratory distress, ultrasound is vastly superior to supine or semi-recumbent CXR for diagnosing pneumothorax.

Back to the Case

Because of the presence of lung sliding on US, a CT scan was performed. This showed emphysematous changes, worse in the right hemithorax, without pneumothorax (Figure 2). The patient avoided an unnecessary tube thoracostomy that likely would have caused deterioration from an iatrogenic pneumothorax. The cause of the false positive CXR finding was a skin fold combined with diminished lung markings peripherally due to emphysema.  The patient was subsequently treated as a COPD exacerbation, and improved clinically.

This post was edited by Sarah Luckett-Gatopoulos @SLuckettG


1.  Adhikari S, Zeger W, Wadman M, Walker R, Lomenth C. Assessment of a human adaver model for training emergency medicine residents in the ultrasound diagnosis of pneumothorax. Biomed Res Int. 2014. (Epub ahead of print)

2.  Alrajhi K, Woo MY, Vailancourt C. Test characteristics of ultrasonography for the detection of pneumothorax: a systemic review and meta-analysis. Chest 2012;14:703-8

3.  Alrajab S, Youssef AM, Akkus NI, Caldito G. Pleural ultrasonography versus chest radiography for the diagnosis of pneumothorax: Review of the literature and meta-analysis. Crit Care 2013;17:R208

4.  Beres RA, Goodman LR. Pneumothorax: detection with upright versus decubitus radiography. Radiology. 1993;186 (1): 19-22

5.  Carr JJ, Reed JC, Choplin RH, Pope TL Jr, Case LD. Plain and computed radiography for detecting experimentally induced pneumothorax in cadavers: implications for detection in patients. Radiology. 1992;183(1):193.

6.  Ding W, Shen Y, Yang J, He X, Zhang M. Diagnosis of pneumothorax by radiography and ultrasonography: A meta-analysis. Chest 2011;140:859-66

7.  Mennicke M, Gulati K, Olivia I, Goldflam K, Skali H, Ledbetter S, Platz E. Anatomical distribution of traumatic pneumothoraces on chest computer tomography: Implications for ultrasound screening in the E.D. Am J Emerg Med 2012;3:1025-31

8.  Volpicelli G, Elbarbary M, Blaivas M, Lichtenstein DA, Mathis G, Kirkpatrick AW, Melniker L et al. International evidence-based recommendations for point-of-care lung ultrasound. Intensive Care Med. 2012;38:577-591

9.  Wilkerson RG, Stone MB. Sensitivity of bedside ultrasound and supine anteroposterior chest radiographs for the identification of pneumothorax after blunt trauma. Acad Emerg Med 2010;17:11-7

Review by an Attending
Expert Review by Dr. Paul Olszynski, University of Saskatchewan

This is a great write-up! Well written, good flow with key findings clearly explained.

As Jacob states, most of the cited studies looked at supine films. The authors of one meta-analysis [1] did make note this may underestimate the performance of non-supine chest radiographs (upright and semi-upright). Conventional medical teaching (yikes!) and the above-mentioned evidence suggest that upright posterior-anterior films are superior to supine chest radiographs. By how much? Hard to say, but I suggest it’s worth addressing.

Emergency physicians regularly diagnose spontaneous pneumothoraces in their dyspneic/short of breath (SOB) patients using upright chest films (inspiratory, expiratory—you name it!). Many have come to trust these images much more than supine films, and l suspect many of our colleagues will want to know how the different types of chest radiographs measure up (not to mention how well pleural ultrasound performs in assessing the SOB differential: effusion, consolidation, edema, etc…a post for another time I suppose!).

The performance of an upright posterior-anterior chest radiograph for the detection of pneumothorax is oddly difficult to find. One study from the American Journal of Roentgenology (AJR) [2] allows us to (slightly) side-step that question by instead comparing upright CXR to ultrasound in 285 patients who had undergone lung biopsy. With the limitations of being a small study, and these pneumothoraces being iatrogenic, the authors showed ultrasound was at least as good as an upright CXR.

Where does this leave us? As Jacob points out, in the supine patient, pleural ultrasound is superior to chest radiography. As for our non-supine patients (the ones with those spontaneous pneumothoraces that usually present and remain upright during bedside assessment), the limited evidence for ultrasound looks promising. I’d suggest you place them supine, have a good look as described in the post, and prepare yourself to know a lot more about your dyspneic/SOB patients, the risks they are facing before leaving for tests, and their disposition, long before they get that upright CXR.

Paul Olszynski, MD, MEd, CCFP (EM)


1. Alrajab S, Youssef AM, Akkus NI, Caldito G. Pleural ultrasonography versus chest radiography for the diagnosis of pneumothorax: Review of the literature and meta-analysis, 2013.

2. Sartori S, Tombesi P, Trevisani L, Nielsen I, Tassinari D, Abbasciano V. Accuracy of Transthoracic Sonography in Detection of Pneumothorax after Sonographically guided Lung Biopsy: Prospective Comparison with Chest Radiography. AJR, Jan 2007.

Author information

Jacob Avila
Jacob Avila

The post Boring Question: How does the sensitivity/specificity of lung ultrasound compare to plain films in diagnosing pneumothorax? appeared first on BoringEM and was written by Jacob Avila.

10 Tips from Nurses to Rock Your EM Clerkship

There are lots of ways to prepare for clerkship, like finding mentors, reading up, and making learning goals, as outlined in this past post. While those tips will help you maximize your skills building and demonstrate your professional competencies, it’s also important to use clerkship as an opportunity to learn how to work as part of an interdisciplinary team within a complex health care system. There is growing recognition that quality care and patient safety depend on teamwork, and evidence demonstrates that increased collaboration between physicians, nurses, and allied health professionals helps improve client outcomes [1]. With that in mind, here are tips from nurses to help you work with respect and synergy as part of the team.

10 Tips from Nurses to Rock Your EM Clerkship

Tip 1 – Be courteous

Often health care providers can be so focused on their patients and the endless tasks at hand that we can forget what it means to be courteous. Emergency departments can be hectic places full of people in crisis, but we can still take a few moments to exercise common courtesy with our colleagues. Start conversations with “hello” or “how are you?” and introduce yourself (#hellomynameis isn’t just for patient interactions). This allows us to build professional relationships from a place of trust and respect.

Other daily courtesies apply to workplace settings, too. Respectful and polite language, like saying “please” and “thank you”, sharing workspaces, returning supplies and charts when you’re finished with them, remembering to log off computers – all of these things help improve workflow and can make a sometimes chaotic environment just a little more pleasant. Other tips for being courteous in the workplace are available from the business sector here.

Tip 2 – Capitalize on other people’s expertise

There’s a reason that health care has interdisciplinary teams with specialties and sub-specialties – we can’t all know everything. Make the most of the variety and depth of knowledge that surrounds you. Nurses, especially, know the patients, staff, policies, and hospital well, and appreciate being recognized as a resource. We are (typically) with our patients for 8-12 hours at a time and are very familiar with their baseline status, so please trust us when we are worried, and listen to our concerns. This interesting paper takes a “pragmatic view of intuitive knowledge in nursing practice” and highlights the importance of a nurses’ intuition [2]. We’re also happy to show you what we know, especially if you’ll teach us something, too.

Tip 3 – Strategically pick your timing

Research shows that, like physicians, nurses also face many interruptions. One study showed that nurses are interrupted once every 6 minutes [3]. While it’s great to ask questions, solicit and give feedback, and have an open dialogue with colleagues, there are better and worse times for these discussions. Refrain from interrupting procedures, and wait until we have completed our assessment to start yours. Know that all health care providers are juggling a lot of competing priorities, and although we want to support your learning and attend to your patients, we may need to prioritize something else, so please be patient. Having said that, if you have immediate concerns about patient safety, speak up.

Tip 4 – Strategically pick your location

Pick your location wisely when questioning someone’s practice or debating a plan of care. Don’t do so in front of a patient, unless there is an immediate safety concern or bedside rounds are standard at your institution. Those conversations are probably best saved for the charting station, not the hallway, where patient confidentiality is easily compromised. When picking a location to do extra reading or learning, choose somewhere where you won’t be interrupted by people maneuvering around you for supplies or charts. When picking a location to watch a procedure, be mindful of sterile fields and introduce yourself to the patient and provider(s) rather than silently hovering.

Tip 5 – Practice Stewardship: Leave your patients, colleagues and the department how you found them or better

Nothing feels more disrespectful than someone leaving their mess for me to clean up. It’s definitely best practice to remove bedding, clothing, dressings and diapers to examine your patients, but please put them all back when you’re done. If there’s a complex wound, feel free to ask when the next dressing change is so that you can assess it then, or at least let the nurse know that you’ll have to remove a dressing so we can plan our care accordingly. Return or throw-out supplies when you’re finished a procedure, and dispose of all your sharps properly. If you don’t know where something goes, ask instead of putting it away in the wrong place. Ask your colleagues how you can help and what you can do to help make their job easier. Ask patients if there is anything they need before you leave the room.

Tip 6 – Take responsibility for patient safety

Little things make all the difference, even when you are a medical student. Leaving patients in better shape than you found them is also about patient safety. This means assuring that bed-rails are put back up and the call-bell is within reach. A significant number of patients experience adverse events in the hospital, especially falls [4]. Keep this in mind when mobilizing patients, and communicate fall risk with the rest of the healthcare team.


Hand hygiene is an important part of patient safety – so important that it warranted its own section. We all know that practicing hand hygiene is the number one way to reduce the spread of infection. But it’s incredible how few healthcare providers do it properly or as often as they should. Brush up on best practices and follow them.

Tip 8 – Do not touch things if you don’t know what they are

If you’re going to change or remove any tubes, pumps, IVs, or ventilator settings, please let us know. Unless you are totally familiar with how to use them, please do not touch them without asking first, as the nurse probably spent a significant amount of time setting them up, untangling them, and completing safety checks. If you’re curious about what a patient is hooked up to, just ask! Also, it’s best to keep your hands to yourself when observing a sterile procedure.

Tip 9 – Take care of yourself

Adjusting to long shifts can be physically and mentally exhausting. It’s harder to care for others if we’re not caring for ourselves. It’s your own responsibility to assure that you’re fed and watered and ready to learn. We are all doing what we can to take care of ourselves and our patients, so please don’t rely on others to take care of you, too. Remember, many of your nursing colleagues have had years of experience with working shifts. If you’re having trouble, reach out to them, as they will likely have some tried and true tips to share.

stolen foodTip 10 – Do not steal anyone’s snacks

Just trust me.

Acknowledgements: Thanks to my colleagues for their input on this post, including the nurses at BC Children’s Hospital and those who contribute to the online forums at reddit/r/nursing. Check out the great Reddit feed started by Claire for even more advice. 

This post was edited by Teresa Chan and Eve Purdy.


  1. Martin, J. S., Ummenhofer, W., Manser, T., & Spirig, R. (2010). Interprofessional collaboration among nurses and physicians: making a difference in patient outcome. Swiss Med Wkly, 140, w13062.
  2. Billay, D., Myrick, F., Luhanga, F., & Yonge, O. (2007) A pragmatic view of intuitive knowledge in nursing practice. Nurs Forum ; 42(3): 147-55. (
  3. Kalisch, B. J., & Aebersold, M. (2010). Interruptions and multitasking in nursing care. Joint Commission Journal on Quality and Patient Safety36(3), 126-132. (
  4. Hitcho, E. et al. (2004). Characterstics and circumstances of falls in a hospital setting. J Gen Int Med; 19(7): 732.789. (

Author information

Eve Purdy
Medical Student Editor at BoringEM
Fourth year medical student at Queen's University-happily consuming, sharing, creating and researching #FOAMed

The post 10 Tips from Nurses to Rock Your EM Clerkship appeared first on BoringEM and was written by Eve Purdy.

Tiny Tip: HELLP Syndrome

If you train in a tertiary care center with obstetrical triage, you may not assess many pregnant women beyond the first trimester of pregnancy. However, in community emergency departments without a primary obstetrics triage department, you will often encounter pregnancy-induced hypertension (PIH; systolic pressure 140 mmHg, or diastolic pressure 90 mmHg), a common complication occurring in 7-9% of pregnancies. HELLP syndrome is an important subset of PIH that comes with its own built-in mnemonic to help remember its features[1].

The Mnemonic: HELLP Syndrome

HELPP syndrome is comprised four component parts [2]:



Liver enzymes



Applying the Mnemonic

If you encounter a pregnant woman with hypertension in the emergency department, be on the look out for signs of haemolysis (the peripheral blood smear and elevated LDH are your clues), elevated AST and ALT, and thrombocytopaenia. Clinical symptoms of acute hypertensive disease, including epigastric or right upper quadrant pain, headache, paraesthesias, and blurred vision may contribute to the clinical picture. Prolonged prothrombin time and low fibrinogen level are indicators of severity, and uric acid is used as an adjunct used for diagnosis in some centers.

The only cure for HELLP syndrome is delivery, but patients may be temporized with fluids, antihypertensive agents, and platelet transfusion, depending on the clinical picture. Consult obstetrics early.



Review by an Attending

Thank you very much for your piece. I enjoyed this review, and thought it represented the topic well. One thing I would suggest is that it is critical to consider the key differences between HELLP and other PIH-related entities.

Of note, within this recent update of the Society of Obstetricians and Gynecologists of Canada (SOGC) guidelines they state that:

“Definitions of severe preeclampsia vary, but most include multi-organ involvement. We modified our definition of severe preeclampsia to preeclampsia associated with one or more severe complications. Severe preeclampsia now warrants delivery regardless of gestational age. Our definition excludes heavy proteinuria and HELLP syndrome, which are not absolute indications for delivery, and includes stroke and pulmonary edema, which are leading causes of maternal death in preeclampsia.” – Pg 422, SOGC guidelines [2]

For Canadian learners, it is best to understand that there is controversy about definitions of severe preeclampsia internationally. The SOGC, however, is the main body that sets the national standards in Canada. Hence, it is worthwhile being familiar with what our Canadian experts have defined as Severe Preeclampsia – and with the 2014 guideline, it is noted that they excluded heavy proteinuria and HELLP syndrome from the definition for preeclampsia because these two diagnoses are not absolute indications for delivery.

That said, on page 421 they state that:

“HELLP syndrome is represented by its component parts (hemolysis, elevated liver enzymes, and low platelets), to which we react to by initiating delivery.”

This statement implies that usually a patient presenting with HELLP may very well require emergent delivery. As such, it is imperative, as you have stated, to alert obstetrics early and involve them in the decision making for this case.

One more note, the 125th recommendation urges practitioners to bear in mind the delay between ordering and receiving platelets (Level III-B) – and hence, if you are a first line practitioner with a patient whose platelets are low, it will be important to alert the obstetrical team and perhaps even begin ordering (+/- transfusing) platelets if the patient has HELLP syndrome (and particularly if the platelet count is < 20 x 109 /L as detailed in recommendation 126 (Level III-B). [2, p. 432]).

Addendum (Aug 14, 2014 12:03pm): Of note, the pregnancy-induced hypertension pathologies can occur in women in the postpartum period.  At the 6 week postpartum check up it is important to consider this critical diagnosis. (Thanks to Taylor Zhou for requesting this amendment as a post-publication peer review.)



1. Nabhan, A., & Elsedawy, M. (2011). Tight control of mild-moderate pre-existing or non-proteinuric gestational hypertension. The Cochrane Collaboration. Retrieved from

2. Rey, E., Pels, A., von Dadelszen, P., Helewa, M., & Magee, L. (2014, May). Diagnosis, evaluation, and management of the hypertensive disorders of pregnancy: Executive summary. Retrieved from PMID: 21735406

Author information

Sarah Luckett-Gatopoulos
Sarah Luckett-Gatopoulos
Junior Resident Editor at BoringEM
Sarah is a resident at McMaster University. She has an interest in creative writing and health literacy.

The post Tiny Tip: HELLP Syndrome appeared first on BoringEM and was written by Sarah Luckett-Gatopoulos.

Boring Question: Dizzy, need a few HINTS?

The dizzy patient. If you haven’t seen a patient with this chief complaint, you either don’t work in an emergency department or you work in an imaginary emergency medicine utopia! Admit it, when you pick up the chart that reads “chief complaint…dizzy”, you look around inconspicuously, slowly replace that chart in the rack… and run quickly become preoccupied with some fascinating task from… oh… somewhere over there! But why? It is not because we do not like dizzy patients… It is because when the patient complains of ‘dizziness,’ it can mean so many things that it makes it hard for us to diagnose and solve the problem.

“Dizzy” is a vague problem that can be caused by a long list of diagnoses including critical or life-threatening diagnoses (e.g. posterior circulation infarction) that mimic benign causes of dizziness. Wouldn’t it be great if there was a blood test to rule-out serious pathology among dizzy patients? Unfortunately, we’re more likely to put humans on Mars than come up with such a test, so instead we are left to work up dizzy patients using our clinical skills and some focused diagnostic tests. 

This post will present the case of a dizzy patient and outline how the HINTS examination can be integrated into our evaluation.


A 72 year old woman presents after acute onset “dizziness” that has been continuous for 36 hours. She describes feeling nauseated (without vomiting) and unsteady while ambulating. She has a history of hypertension but no other relevant medical history. Her vital signs are normal and exam demonstrates slight difficulty walking and horizontal nystagmus on right lateral gaze. The remainder of neurologic exam is normal. You wonder if this could be a posterior circulation infarct or is it simply a benign case of vertigo? You can’t get an MRI easily for several days so the decision needs to be made now. While you are considering your super keen medical students asks if the HINTS exam can play a role in sorting out the diagnosis for this patient.

Boring Question: What is the role of the HINTS examination in the evaluation of the dizzy patient?

The Head Impulse Nystagmus Test of Skew (HINTS) exam is a promising bedside test designed to differentiate between peripheral and central causes of acute vestibular syndrome (AVS). AVS is characterized by acute onset vertigo with associated nausea/vomiting, nystagmus, unsteady gait and head motion that persist >24hrs [1]. In most instances, HINTS is used to differentiate between vestibular neuritis and a posterior circulation infarct. However it may also identify other important central causes of AVS including mass lesions or demyelinating syndromes [2].

The HINTS Test comprises 3 parts [2]

  1. Head impulse test (HIT) – the examiner performs rapid, passive head rotation of the patient while the patient fixates on the nose of the examiner; a peripheral etiology will cause a corrective saccade that is considered “abnormal” while a central cause of vertigo will lack any saccade thus considered “normal”. Bottom line is that “abnormal” is a good thing for the HIT and “normal” suggests a central etiology
  1. Nystagmus type – identification of nystagmus type by smooth pursuit of extra ocular movements:
    1. Central etiology = bilateral, direction-changing, horizontal nystagmus or primarily vertical nystagmus
    2. Peripheral etiology = nystagmus is unilateral, horizontal nystagmus
  1. Test of skew (alternate cover test) – in central causes of vertigo, covering of one eye results in subtle movement of the uncovered eye

This may be a bit overwhelming so I recommend watching this great video describing the HINTS exam [3,4]


 HINTS exam in peripheral vertigo

Unilateral “abnormal” head impulse test PLUS unilateral horizontal nystagmus without any skew deviation.

 HINTS exam in central vertigo

Any of, or combination of the following:

1)     bilateral “normal” HIT with any spontaneous or gaze-evoked nystagmus

2)     bilateral, direction-changing, horizontal gaze-evoked nystagmus

3)     skew deviation

Try using the mnemonic INFARCT to recall the findings in central vertigo. INFARCT = (Impulse Normal or Fast-phase Alternating or Refixation on Cover-Test) [7]


  • Very strong – several studies report HINTS to be highly sensitive (96-100%) and highly specific (85-98%) for identifying stroke among patients with AVS [2, 5]
  • Impressively, HINTS exam was also more accurate than MRI to diagnose stroke in patients with AVS within the first 48hrs of symptoms [2]
  • Most studies used HINTS to differentiate posterior stroke from peripheral causes of AVS but it can be broadly to differentiate between any central vs peripheral pathology [6]
  • A recent review highlights the impressive accuracy of HINTS in vertigo [6]


  1. It should ONLY be used for persistent and continuous vertigo. A patient without vertigo during the exam will have a “normal” head impulse test which is the same finding that will occur in a patient with central vertigo
  1. The few studies that exist have enrolled patients with vertigo >1hr since most patients present soon after the onset. So while AVS is technically defined as >24hrs, you can use the HINTS exam if it’s <24hrs as long as the symptoms are continuous
  1. Most of the studies required that patients had at least one risk factor for stroke. As a result the populations studied may have a higher risk of a central etiology. At this time it is unclear the accuracy of HINTS among lower risk populations (e.g. 40 year old male without any other risk factors)
  1. In one study patients were included if they had “vertigo” or “dizziness” plus the other components of AVS . So don’t necessarily exclude your patient because they don’t use the term “vertigo” [2]. However, do your best to establish that they’re experiencing the sensation of movement (either self- or external referenced)
  1. Finally, the majority of studies evaluating the utility of HINTS had highly trained clinicians performing the neurologic evaluations [2,5,8]. The data has not been externally validated among a general population of emergency physicians. So proceed with caution! We shouldn’t expect the same high sensitivity and specificity when used by non-expert clinicians.


Symptomatic relief using anti-nausea medications results in some symptomatic improvement of the patient but the symptoms do not entirely resolve. You perform the HINTS exam on the patient. She has a “normal” head impulse test without any saccade. She has unilateral, gaze-evoked nystagmus without any vertical or bidirectional nystagmus. And there is no skew deviation. Based on these findings you’re concerned there is a central cause for her vertigo. She is referred and admitted to the neurology team. An MRI the following day confirms a cerebellar infarct.


  • The HINTS exam has an important role in the evaluation of AVS based on existing data
  • It is highly accurate in identifying central causes of AVS, perhaps superior to MRI in early stages
  • These impressive results we however comes from one centre where highly trained experts performed the exam so if there is any uncertainty do not rely exclusively on HINTS for diagnosis

This post was edited by Teresa Chan (@TChanMD)


1. Hotson, J. R., & Baloh, R. W. (1998). Acute vestibular syndrome. New England Journal of Medicine339(10), 680-685. DOI: 10.1056/NEJM199809033391007

2. Newman‐Toker, D. E., Kerber, K. A., Hsieh, Y. H., Pula, J. H., Omron, R., Saber Tehrani, A. S., … & Kattah, J. C. (2013). HINTS outperforms ABCD2 to screen for stroke in acute continuous vertigo and dizziness. Academic Emergency Medicine20(10), 986-996. Link

3. EMCrit and the original source of the videos is

4. Newman-Toker D. 3-Component H.I.N.T.S. battery. (2009). Retrieved at:

5. Chen, L., Lee, W., Chambers, B. R., & Dewey, H. M. (2011). Diagnostic accuracy of acute vestibular syndrome at the bedside in a stroke unit. Journal of neurology258(5), 855-861. DOI: 10.1007/s00415-010-5853-4

6. Cohn, B. (2014). Can Bedside Oculomotor (HINTS) Testing Differentiate Central From Peripheral Causes of Vertigo?. Annals of emergency medicine. In Press. DOI: 10.1016/j.annemergmed.2014.01.010

7. Newman-Toker D. Acute Vestibulary Syndrome (n.d.) Retrieved at:

8. Kattah, J. C., Talkad, A. V., Wang, D. Z., Hsieh, Y. H., & Newman-Toker, D. E. (2009). HINTS to diagnose stroke in the acute vestibular syndrome three-step bedside oculomotor examination more sensitive than early MRI diffusion-weighted imaging. Stroke40(11), 3504-3510. DOI: 10.1161/​STROKEAHA.109.551234

Author information

Andrew Petrosoniak
Andrew Petrosoniak

The post Boring Question: Dizzy, need a few HINTS? appeared first on BoringEM and was written by Andrew Petrosoniak.