Weekly Review #9

ScanCrit reviewed a case report of double sequential defibrillation (DSD) published in the journal of Prehospital Emergency Care. DSD is a process of hooking a patient up to two defibrillators and providing sequential shocks. In this particular case the patient had refractory V-Fib and had received 7 unsuccessful shocks with lead placement changes. The team performed DSD using the standard anterior/apex as well as anterior/posterior placements, with the deliver shock button pressed as close to simultaneously as possible. DSD converted the patient to sinus rhythm, who went on to survive to discharge. The exact mechanism of why DSD works when standard defibrillation has failed is not known, there haven't been any good quality trials performed to date; until that happens this care report is unlikely to significantly change current practice. DSD is an exciting concept: it's a novel approach, and one that can easily be deployed without expensive new equipment. This may not be a game changer in the management of refractory arrest, but it's at least one more tool.

http://www.scancrit.com/2015/07/07/one-two-punch/#more-8222




On July 8 & 9th I participated in the inaugural Eastern Association for the Surgery of Trauma (EAST) journal club discussion. It was on an study published the Journal of Trauma and Acute Care Surgery on the use of hemostatic foam in recently deceased cadavers. The study by Mesar et al., was attempting to determine what a safe dose of foam would be. Essentially the team wanted to extend their animal models to humans to determine how much intra-abdominal pressure, and internal organ contact would be made with differing volumes of injectable foam.




The study used recently deceased cadavers (146 minutes, ± 34min), added IV fluids to the abdominal cavity to mimic blood volume, and injected foam into the cavity. Intra-abdominal pressures (IAP) where monitored and the abdomen measured every minute for 15 minutes; after 15 minutes the foam was removed to evaluate the amount of contact with internal organs.

Of the 409 patients screened 21 were recruited, 18 met inclusion criteria, 3 of the patients were excluded from the final results due to errors in administering the foam. 4 cadavers received either 45, 55, or 65mls of intra-abdominal foam using one of two purpose built delivery systems. The foam quickly reached peak volume, the resulting increase in IAP fell below the maximum threshold of 65mmHg; while the cadaveers given larger doses exceeded the IAP cutoff.

After 15 minutes the Cadavers all successfully had the foam block removed, in one piece, by laprotomy. The contact with underlying organs was noted in each case, and the average contact areas was determined. Best coverage, unsurprisingly, occurred with larger doses, and the foam didn't absorb extra fluid.

The goal of this study was to determine what a "safe" dose of intra-abdominal foam would be, and it appears that doses of 65ml will generally fall below their IAP cutoff of 65mmHg. There are some limitations to this study: the sample size is quite small, and IAP results appear to vary significantly between cadavers receiving similar doses, making predictions on average IAP by dose would be difficult. The delivery system could also use improvement, of 18 attempts there were 3 (16%) errors, one of which resulted in accidental bowel perforation. From a clinical perspective I think that this technology still needs a fair bit of refining: there is no clearly articulated target population (injury mechanism). The intent is clearly hemorrhage control, but the foam is too superficial to access major vessels (which is fine, REBOA can do that), but it also has poor contact with solid organs at doses below the IAP cutoff.

From a nursing perspective I think that this technology is exciting, abdominal bleeds account for a large number of battlefield deaths, and any tools that can increase survival for these injuries is worth investigating. I'm looking forward to additional research on this technology, and would love to see if can be used in human trials.

The moderators at the EAST journal club did an excellent job. Responses to questions were generally rapid, and they were able to offer some additional information not explicitly stated in the research article. I look forward to the next journal club discussion, this and future reviews are on twitter at #EASTjc.

http://journals.lww.com/jtrauma/Fulltext/2015/07000/Human_dose_confirmation_for_self_expanding.6.aspx







Ryan Radecki from emlitofnote had a post reviewing the specificity and sensitivity of urinalysis for UTI in febrile pediatric patients. This is a 15 year 276 patient multicenter review of infants less than three months of age with fevers, bacteremia and UTI. The goal of the study was to determine how effective urinalysis as in predicting urinary tract infection. The results are surprisingly positive, as a predictive tool urinalysis is impressively accurate: 

• Trace or greater leukocyte esterase: 97.6% (94.5-99.2) sensitive and 93.9% (87.9-97.5) specific.
• Pyuria, >3 WBC/HPF: 96% (92.5-98.1) sensitive and 91.3% (84.6-95.6) specific.
• Pyuria or any LE: 99.5% (98.5-100) sensitive and 87.8% (80.4-93.2) specific.

These results are interesting because as a screening tool UA alone is generally not effective in adult or geriatric populations. All three of these are worth a review, as the differing conclusions offer an excellent case study in Bayesian statistics and determining likelihood ratios. From a nursing perspective having a non-invasive tool with high diagnostic power is great news, taking blood from an infant is traumatic for the care team, the parents, and most importantly the patient.  

http://www.emlitofnote.com/2015/07/the-utility-of-urinalysis-in-young.html

A new study published in Critical Care by Acheampong and Vincent examined the relationship between fluid balance and mortality in ICU patients admitted with sepsis. This study was a prospective observational study of 173 patients admitted to a single Belgian ICU for sepsis in 2012. Inclusion criteria were: patients >15 years of age, admitted to ICU >48hrs for sepsis. These patients were treated using the "surviving sepsis" guidelines. Total enteral/parenteral volumes were recorded against total sensible fluid loss to determine net fluid balance; there were 225 patients enrolled, 173 met inclusion criteria. Patients with a net positive fluid balance, or in septic shock were more likely to have poor outcomes. Overall ICU mortality rate was 34%, and the results suggest that positive fluid balance was associated with an increase in mortality (HR 1.014/ml/kg: 1.008-1.027, P<0.001). Non-surviving patients however tended to be sicker (SOFA score 9.0±3.3 vs 7.7±3.3), to be in septic shock (97 vs. 68%), and to have an infection of pulmonary origin (53 vs. 30%). There were significant differences between groups; unfortunately vital sign parameters, and rates of vasopressor use were not discussed, making it impossible to determine if the relationship between fluid balance and mortality is one of cause or effect. This was a small single center study with no control arm, we know the patients who didn't survive tended to be sicker, and to be in septic shock: they likely needed more fluids to maintain BP and likely had higher rates of vascular leakage and therefore fluid retention. This study does establish that positive fluid balance is prognostic of mortality, but we knew that, from a nursing perspective this study adds little to our understanding of sepsis, or fluid resuscitation.

http://www.ccforum.com/content/19/1/251




TamingtheSRU had a discussion posted on their site by Dr. Brian Burns from Sydney HEMS. Where he was discussed the concepts of marginal gains, or aggregation of gains, and how they can be used to improve pre-hospital patient care. The talk wasn't about medical or technical skills; rather it focused on different human factor aspects of self mastery. There were several methods reviewed, but the discussion focused primarily on tools such as cognitive offloading, cognitive buildups, and cognitive rally points. Dr. Burns emphasized the usefulness of simulation, not only for difficult skills that are seldom performed, but also for common skills that need constant practice, and how to perform common skills in uncommon scenarios. This is an excellent video for all clinicians, as a nurse it's great to see some of the best clinicians around discussing simple strategies such as visualization and checklists, strategies that everyone can use to improve their everyday performance, as well as their performance in critical moments.


http://www.tamingthesru.com/blog/prehospital-medicine/when-that-1-makes-all-the-difference

Weekly Review #7

Eve Purdy posted on BoringEM about critical appraisal of research. Critical appraisal tools equip readers of research with a method of interpreting the rigor of the methods, and a way of examining if the results are meaningful: both statistically and clinically. There are some links in the post to the Center for Evidence Based Medicine (CEBM) at Oxford: which has great tools for assessing research, as well as brief explanations on some of the statistical tools used in EBM. There is also some links to access YouTube hosted videos on statistical tools, and some other web based education opportunities. I think that the ability to critically interpret research is fundamental to becoming a proficient end user of research, I've discussed different tools that are available to help use statistics in health care previously (see diagnostic test calculor in weekly review #6, and Liklihood Ratio Database in Weekly Review #4) because there's so much research being produced that it's not only difficult to ensure that all of the research is high quality, but that it's also relevant to the question at hand. I would also suggest reading some previous posts by ScanCrit, emlitofnote, and BoringEM, which all do a great job of highlighting the disconnect that can occur between statistical and clinical significance.

http://boringem.org/2015/03/06/boringem-research-week-skimming-the-top-off-researchclinepi-foam/




A Dutch study examined the effects of Crew Resource Management (CRM) training on ICU mortality and complication rates. CRM is a training program used in aviation to examine human factors in adverse outcomes and create system solutions to prevent them from occurring. The CRM intervention consisted of two days of training in CRM for all staff, the designation of CRM team leaders, and the identification of, and strategies for dealing with, 8 key human factors that result in adverse outcomes.




The 8 key areas were:
1. Situational awareness: and recognizing adverse situations;
2. Human errors and non-punitive responses to them;
3. Communication, briefing and debriefing techniques;
4. Providing and receiving performance feedback;
5. Stress management, workload and fatigue;
6. Creating and maintaining team  structures and environments;
7. Leadership in a flat hierarchy;
8. Risk management and decision making.


Strategies became topics of discussion at all staff meetings, and staff created new checklists for key points in patient care: Central line placement, ET intubation, patient handover at transitions in care, and team training.

The study was a single center 3 year before/during/after prospective cohort design, there was no control arm, and all the data for the study was pulled from the Dutch NICE registry. Approximately 2230 to 2500 patients were included in each of the three years, and were assessed for 18 key complications.

With the introduction of the CRM training: overall complication rates decreased, mortality decreased, cardiac arrest rates went down, CPR success increased from 19% at base line to 55 in the intervention year and 67 in the post implementation year, and staff perceived the work environment to be safer in general. There were no differences in LOS or ICU LOS.



These findings are encouraging; however. there are some limitations to this study: it's single center, has a small population, and no control so the quality of the evidence could be stronger. There is no standardized approach to CRM training in health care, so applying this model to another site could prove difficult, therefore reproducibility may be poor. The study ICU also changed location in the first month of the post-implementation year: while the authors acknowledge that the ICU used the same equipment, the change in environment could have improved work flow and contributed to improved outcomes. Finally if we examine the patients year on year we can see that there was a decrease in cardiac patients and patients with chronic cardiac conditions which certainly could have attributed to the decreased cardiac arrest rates. Overall rates of vasopressors and mechanical ventilation use decreased; while trauma admissions increased, which certainly could have a large effect on the overall mortality and complication rates. From a nursing perspective there is some encouraging news here, if due to the intervention, the reduction in  complications/cardiac arrests and increase in CPR success is substantial. Certainly the intention is good: addressing systems processes to prevent human error. However; Until there's larger studies and standardized CRM training it will be difficult to determine if CRM training is a worthy intervention.

http://onlinelibrary.wiley.com/doi/10.1111/aas.12573/pdf





There was a ton of information and MedEd sharing happening last week with the social media and critical care (smaccUS) conference happening in Chicago. Too much to cover everything in detail, but there are a few pieces that I found particularly interesting and relevant to nursing:


@HEFTEMCAST had a great post on the utility of urinalysis on detection of UTI. This links nicely to earlier discussions on understanding test probabilities and evidence based medicine. In this post they discuss the sensitivity and specificity of the different parts of the urine-dip, and the risks for false positive if pre-test probability is not used in determining the likelihood ratio. The take-home message here is that bacteriuria is relatively common in elderly patients, especially females, and doesn't always warrant antibiotics. I think a review of urine dip testing is particularly relevant for nurses, as I inwardly cringe every time I hear a colleague discussing a "dirty" urine dip on an asymptomatic patient.

http://www.heftemcast.co.uk/urine-testing-who-gets-the-antibiotics/
http://www.sign.ac.uk/pdf/sign88.pdf





A problem for all clinicians is how to deal with patients who have presented with dubious conditions, requesting opioid analgesics. For nurses this is somewhat less of an issue, from a liability perspective, than it it for our medical counterparts. However dealing with these patients can be frustrating. There are some slides made available from a smaccUS talk discussing the myths and realities of prescription opioid use, the current state of evidence, red/yellow flags for spotting potential opioid abuse/abusers, as well as some phrases to help in communicating with these patients. From a nursing perspective I think the flags will likely recap some of the obvious clues that many nurse will already have identified, there may be a few flags you had not thought of, and even more helpful it may provide some useful terminology to describe the behaviour of patients who are gaming the system for narcotics. Most important information however is directed at clinicians themselves, an honest critique of poor clinical practice, and the myths of opioid pain control: That narcotics are non-addicting in patients experiencing pain, that we should seek pain scores of zero, and that opioids are effective for chronic pain. If you click on only one link from this post, make this the one!

http://emupdates.com/helpcard-and-opioid-misuse/
http://emupdates.com/wp-content/uploads/2015/06/Strayer-Opioid-Misuse-SMACC-Slideset.pdf




ICEBlog posted their smaccUS notes on clinical education online. There's some great information here for anyone involved in providing or receiving clinical education (everyone). There is a review of teaching/learning styles, some myth busting about clinical education, and a framework model for delivering clinical education. There is also a small teaser on social knowledge, something they unfortunately didn't expand upon.

http://icenetblog.royalcollege.ca/2015/06/26/education-theory-for-the-meded-clinician/





More reasons to use IO access: A great post on ScanCrit about the use of IO access for RSI medications. This is a review of British combat medicine review from Afghanistan, published in the Emergency Medical Journal, on prehospital intubation of injured soldiers. The successful first pass rate for RSI was 97%. The quality of evidence is relatively poor (sample size less than 40, limited generalizability outside of combat helivac operations); but it certainly adds to the growing body of first hand evidence suggesting that IO access is a viable first line choice for gaining vascular access and administering drugs.

http://www.scancrit.com/2015/06/29/io-drugs-quick-iv/

Weekly Review #3

A French research team led by Helene Goulet published a study in Critical Care examining unexpected deaths of patients admitted through emergency departments. This multi-center retrospective study examined the patient records of 4 metro Paris hospitals for death within 72 hours of ED attendance. Exclusion criteria were: admission to ICU, expected death (ex: inoperable intracranial hemmorage), and presence of DNR. Primary endpoint was determining cause of preventable death, secondary endpoints were process breakdowns that may have contribute to death. Of the 208549 admissions during the study period 70 died unexpectedly. Due to incomplete ED records only 47 met full inclusion criteria. 24 of the 47 deaths (51%) were deemed preventable. 55% of these patients died in the ED, 40% in a medical ward. Delay in recognition and treatment of sepsis accounted for 38% of deaths, while under-triage or under-recognition of critical illness contributed to death in 4 (16%) patients. Of the process breakdowns the most common were: incorrect treatment choice (47%), failure to order correct diagnostics (38%), incorrect admission ward (47%), and incorrect triage (45%). Goulet et al acknowledge that previous studies of this nature have not shown sepsis death rates quiet as high, they don't offer specific recommendations other than to stress the importance of recognizing and treating sepsis. This study has some obvious limitations: it has a small sample size and didn't capture unexpected deaths of patients discharged/transferred from hospital. The reviewers were also aware of patient outcome (death), and as such would have been more critical in their reviews; combining this with the current practice changes associated with the Surviving Sepsis campaigns and EGDT could explain the higher than previous rates of mortality associated with sepsis. There was also no discussion on whether or not the unexpected deaths would have been prevented with correct treatment. From a nursing perspective this reinforces the need to be diligent in triage, and speaking up if obvious orders or treatments have been overlooked.

http://ccforum.com/content/19/1/154/abstract




There was a post by Josh Farkas on PulmCrit about sleep protective patient monitoring. The post is essentially suggesting that not all patients need nocturnal blood pressure or temperature monitoring- monitoring which wakes patients up and puts them at increased risk for delirium. As an alternative he suggests using urine output as a corollary measure of cardiac output, as good urine production is a reliable indicator of end organ perfusion. This approach is obviously only possible in patients with indwelling catheters, and should not be used with patients in shock, with cardiac problems, or on diuretics. From a nursing perspective we can all appreciate the frustration at having to wake a hemodynamically well patient from sleep to assess their BP, and this may provide an alternative. While it certainly can't override unit policy, it may provide a step from which to discuss the implications of "routine vital signs" order, and an alternative course of action.

http://www.pulmcrit.org/2015/04/sleep-protective-monitoring-to-reduce.html

There was a post by Ian Miller of The Nurse Path reviewing male Foley catheter and urinary drainage bag stabilization. It appears that there is differing opinion on catheter stabilization techniques: Either to the stomach; or to the thigh.  That it should be in a soft "S" shape is the common point in both methods. He discussed the potential for necrosis due to tension or bending of the penis. Unfortunately he didn't discuss the negative implication of not securing the catheter at all, as happens all too often, and is associated with increased rates of Catheter associated UTI 's, and penile trauma. This post is directly applicable to nursing practice, it questions routine practice, it describes good practices, and the survey could help inform determine where nurses are in their practice. It's worth looking at, and please remember to fill out the survey.

http://thenursepath.com/2014/10/31/are-you-securing-male-catheters-in-the-right-place/?utm_content=buffer6f208&utm_medium=social&utm_source=twitter.com&utm_campaign=buffer

http://thenursepath.com/2014/10/06/tips-on-catheter-and-leg-bag-management/?utm_content=buffer63604&utm_medium=social&utm_source=twitter.com&utm_campaign=buffer

http://www.nursingtimes.net/5003963.article




I came across a post by Barrier & Chow of Critical Caring about oxygen therapy. They have a very readable discussion on the pitfalls and negative effects of unnecessary oxygen use. Specifically they discuss how supplemental oxygen was harmful in neonates with patent ductus arteiosum (PDA). Oxygen in these patients can cause the PDA to prematurely close and result in worse outcomes. They also discuss how supplemental oxygen results in worse outcomes for patients with: STEMI, COPD, Stroke, ARDS, and mechanically ventilated patients in general. Barrier & Chow discuss the four types of hypoxia (there a great explanation on ER/Trauma 101), and how supplemental oxygen should be targeting hypoxemic hypoxia. This post is directly applicable  to nursing practice, we've all received a patient who is inexplicably on oxygen, oxygen is something many nurses give little thought to, and challenging complacency in these "routine" practices can yield great results. The bottom Line? Maybe the your patient can be weaned off of oxygen... or perhaps they don't need it all.

http://www.critical-caring.pro/2014/11/oxygen-savior-or-devil-in-green-dress.html

http://er-trauma101.blogspot.ca/2011/04/four-hypoxias.html



Suzuki et al., published a study on the effects of paracetamol on mortality in ICU patients. This was a retrospective observational study of 4 Australian ICU's, the largest of it's type. It examined approximately 15000 patients greater than 2 years of age who received > 1g paracetamol during their ICU stay. Patients were studied globally, and with additional analyses performed according to route of administration (IV/PO), service (medical/surgical/ICU), temperature (<35, >38, >38.3, >38.5, >39), patients with liver cirrhosis, patients with infections, and by illness severity. The average patient in both groups were male 64 years of age with similar illness scores. The average daily dose of paracetamol in the control arm was 1.9g with an average total dose of 3g. Overall 14% of patients died, patients who received paracetamol were less likely to die (adjusted OR 0.60, 95%CI 0.53-0.68), this relationship persisted throughout further analysis. There was little discussion as to causal factors, although the authors suggest that paracetamol administration may result in diversion away from opioids or NSAID's for analgesia. although this may be true; there were significant differences between arms that could could have contributed to the overall effect. Significantly more of the patients in the intervention arm were admitted after surgery (70 vs. 51%) many of which were elective (55 vs. 37%). Furthermore illness severity scores appear to have determined post-operatively. Surgical patients, especially those presenting for elective surgeries, are likely to be healthier overall than similar patients admitted for medical reasons, unfortunately there is no discussion or adjustment for this, which severely limits the findings of this research. From a nursing perspective this research seems to add little to the breadth of knowledge available for the safety of paracetamol. Fortunately there are some recent systematic reviews of the literature that suggest there is no difference in mortality in patients given paracetamol; and a RCT is underway.  

http://ccforum.com/content/19/1/162/abstract

Cremasteric Reflex

The cremasteric reflex is a superficial reflex that can be exceptionally useful in assessing testicular emergencies. The cremasteric reflex is a contraction of the cremaster muscle, in response to the stroking of the thigh, which results in retraction of the testicle. Absence of the reflex is an ominous sign when assessing an acute scrotum.

When assessing an acute scrotum, the most important condition to rule out is testicular torsion (Ringdahl & Teague 2006). Testicular torsion occurs when the testicle rotates within the scrotum, the twisting out the epididymis results in impaired blood flow, ischemia can ensue rapidly, and can eventually result in loss of the testicle (Ringdahl & Teague 2006).

Testicular torsion usually occurs in the absence of trauma, and without precipitating factors; although an abnormal attachment of the testicle to the scrotum "bell clapper" deformity, present in approximately 10% of males, puts an individual at increased risk. The overall incidence of testicular torsion is estimated at 1 per 4000 in males under age 25, with the highest incidence occurring during the first few days of life, and from age 12-18yrs. (EBMedicine, Ringdahl & Teague 2006). Testicular torsion requires emergency urology referral, as ischemia begins within 4 hours (Ringdahl & Teague 2006). It is precisely for this reason that knowing how to assess for a cremasteric reflex is essential.




When assessing an acute scrotum for testicular torsion one testicle may appear to be shortened due to the twisting of the epididymis, cremasteric reflex may be absent on this side, but the test should be performed bilaterally. To assess cremasteric reflex the thigh should be stroked with a finger, the handle of a reflex hammer, or most commonly with the blade of a tongue depressor. A normal finding is a retraction of at least 0.5 cm; an abnormal, or absent reflex needs immediate referral.





The cremasteric reflex, in the presence of scrotal pain has been estimated at 96-99% sensitive (Ringdahl & Teague 2006, Schmitz & Safranek, 2009); which is to say that the probability of having a false negative is approaching zero percent. Absent reflex is 66-88% specific for torsion, yielding a negative predictive value of 96% (EBMedicine). The caveat to these probabilities is that an absent cremasteric reflex can be considered normal in approximately 50% of infants under the age of 30 months (Ringdahl & Teague 2006). The importance of the high sensitivity from the nursing perspective is that we can be relatively certain that the odds of a false negative are low, and that there will likely be need for urgent referral of these patients.


Correction, or de-torsion of a testicle, can be performed manually with local or procedural sedation; however it is generally addressed through emergent surgical exploration and intervention. Salvage rates are time dependent: surgery within six hours is 90% successful in salvaging the testicle, successful salvage drops to 50% by hour 12, and less than 10% after 24 hours (Ringdahl & Teague 2006). For this reason there is a low threshold for referral and diagnostic studies.

As a nurse knowing how to assess cremasteric reflexes can be exceptionally useful because, in the presence of scrotal pain, an absent creamasteric reflex approaches 100% sensitivity for testicular torsion. Given the short window for surgical intervention, the risks of over-triage, or over treatment due to a false positives are far outweighed by the potential benefit that patients with testicular torsion will experience from rapid referral and intervention.

The cremasteric reflex is a low barrier, easily performed physical assessment. It is a highly sensitive screening tool for patients who need immediate physician attention and surgical referral.




Ringdahl, E., & Teague, L. (2006). Testicular Torsion. American Family Physician, 74(10).

Schmitz, D., & Safranek, S. (2009). How useful is a physical exam in diagnosing testicular torsion?. Clinical Inquiries, 2009 (MU).

EB Medicine Topics (EB Medicine Topics)., 
http://www.ebmedicine.net/topics.php?paction=showTopicSeg&topic_id=113&seg_id=2275