Grand Rounds Recap 07.08.20
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EFFECTIVE EFFICIENCY WITH DRS. HUGHES & THOMPSON
Definition & Importance
Efficiency is doing things right, simply a rate of output over a rate of input such as how many cars can be produced in a timeframe. Effectiveness is doing right things, such as making a care that will actually sell. Both efficiency (operations) and effectiveness (strategy) are needed to thrive.
The first year of EM training leads to the most significant changes in efficiency. Learning good habits early in training will impact your career.
Common Pitfalls
Multitasking is not a thing; our roles require task switching. with >10 interruptions/hour on average, learning how to complete tasks before switching and minimize interruptions leads to increased efficiency.
Shotgun orders before evaluating a patient often leads to unnecessary labs and imaging, increasing overall length of stay. Consider more than just the patient’s chief complaint, including risk factors and time course, before initiating order sets. Example: Chest pain often warrants an EKG and CXR but not all patients deserve a troponin.
Efficiency is not useful for efficiency sake; keep the goal in mind. Bottlenecks are ever changing in the ED and disposition is the most valuable commodity. This does not mean moving too fast and missing things or that our job is glorified triage, but rather that we need to have a disposition-focused mindset.
Time Management
Time management is a proactive, not reactive, process with time allocation signifying priorities, termed value-based scheduling.
Awareness is knowing how much time it will take to complete a task, often the hardest part. Allocation is designing your goals, tasks, and schedule to effectively use time, such as knowing peak performance time and using time blocking. Adaptation is monitoring your use of time, including managing interruptions and changing priorities.
R4 CAPSTONE BY DR. MAKINEN
Beware of the outside hospital transfer and associated anchoring bias.
If it’s not a horse, it’s a zebra. Be vigilant for patterns that don’t fit the norm. There is time for stewardship and a time for the kitchen sink.
Despite classic teaching, fulminant viral meningoencephalitis may have a neutrophil predominant pleocytosis and early bacterial meningitis may have a lymphocyte predominant pleocytosis.
Zoonotic spillover is an ongoing threat, including HIV/AIDS, COVID19, Powassan virus, and Nipah virus.
Powassan virus is a rare, emerging cause of tick-borne encephalitis in the midwest and northeast with an incidence that has increased by 670% over the past 20 years with 10% mortality rate and 50% of survivors having permanent neurologic deficits.
Nipah virus is a rare, emerging cause of epidemic encephalitis in Indian and Bangladesh capable of sustained human-to-human transmission via droplet and contact spread with a 75% mortality rate.
FOAMED IN PRACTICE WITH DR. LAFOLLETTE
Be active.
FOAMed cannot replace a longitudinal curriculum for learning, as it over-represents certain topics while under-representing others; it is better used as an adjunct and/or actively managed.
Critique always.
Everyone has a bias; know what that bias is before taking what is said as fact. Individual gestalt is unreliable for the evaluation of quality for EM blogs but combined gestalt is more consistent. The reputation of the source, such as dictated by Social Media Index, is often used to assess the individual source but consistent evaluation of citations, primary literature and consistency with other sources is the most reliable way to assess individual articles.
Create.
You can contribute content. While it is not yet consistent whether or not this counts as academic credit, the more rigorous it becomes, the more likely it will be valued. Add to your CV under name such as “non-peer reviewed online publications”. In the future, FOAMed is likely to be more a collaborative process and count for promotion. There will likely be a role for artificial intelligence to monitor case load and deliver content based on deficiencies.
TAMING THE SRU WITH DR. IRANKUNDA - Symptomatic Bradycardia in Adults
Pharmacology
Atropine: Works on the vagus nerve and AV node, thus not useful in cardiac transplant patients and those with advanced heart blocks.
Epinephrine: Provides preload, afterload and contractility which can ultimately be curative depending on the etiology.
Transvenous pacing
Pseudo-capture occurs when the monitor shows an appropriate heart rate but the myocardium isn’t capturing. This can be prevented through verification via
Pulse check using doppler away from the torso
Pulse oximeter
Echo (preferably)
ULTRASOUND “LIT BLITZ” WITH DR. BAEZ
Cardiac/Resuscitation
Presence of cardiac activity on initial US had higher ROSC and survival; small number of patients had a pericardial effusion identified that was able to be acted upon and improved survival. (Gaspari et al, Resuscitation 2016)
POCUS increases duration of pulse checks during CPR. (Huis In’t Veld et al, Resuscitation 2017)
US does not affect survival in undifferentiated shock, as it is your interpretation of the test that can help. (Atkinson et al, Annals of Emerg Med 2018) In fact, early US helps shorten list of potential diagnoses in undifferentiated shock. (Jones et al, Crit Care Med 2004)
Renal
When comparing US and CT for suspected nephrolithiasis, US decreases radiation with no difference in adverse events, admission, or readmissions. While the study excluded older patients and those with uncertain diagnoses, it did include patients with no previous kidney stone history. (Smith-Bindman et al, NEJM 2014)
Gallbladder
CBD measurement on POCUS in the ED is likely unnecessary if there are no other ultrasound findings for cholecystitis and no lab abnormalities based on strict definitions, such as WBC < 11K. (Lahham et al, AJEM 2018)
FAST
Even when excluding patients that went straight to the OR, the FAST exam decreases time to operative intervention for patients with torso trauma. It also decreases complications, length of stay, and total charges to the patient. (Melniker et al, Annals 2006)
When FAST is compared to CT in pediatric trauma, there is poor sensitivity (52%) but good specificity (96%). (Fox et al, Acad Emerg Med 2011)
Soft Tissue
US is more sensitive but CT is more specific when assessing accuracy of abscess identification. US is better at characterizing the contents of the abscess but CT is better able to characterize the extent of the infection. (Gaspari et al, Critical US Journal 2012)
US improves sensitivity and specificity as compared to exam alone for identification of skin and soft tissue infections. (Subramaniam et al, Acad Emerg Med 2016)
Early Pregnancy
High frequency linear transducer decreases the need for transvaginal US imaging for detection of an IUP in up to 33% of patients. (Tabut et al, Am J Emerg Med 2016)
HCG discriminatory zone is not reliable for excluding a normal IUP. (Tabbut et al, Am J Emerg Med 2016)
Aorta
ED physicians can accurately detect AAA on US with 100% sensitivity and 98% specificity. (Tayal et al, Acad Emerg Med 2003)
INTEREST GROUP SERIES: CRITICAL CARE WITH DRS. SHAW, MODI, MAKINEN, & GOTTULA
Cardiogenic Shock Simulation
Not all shock is sepsis. Don’t forget to touch your patients’ skin and think about primary or secondary cardiogenic shock
Cardiogenic shock is defined as decreased cardiac output, which is primarily measured via Swan-Ganz but can be seen through secondary signs. Echo is extremely helpful but be careful with mimics such as stress-induced cardiomyopathy.
Norepinephrine is the first line treatment with dobutamine to follow but is typically most helpful after revascularization.
Cardiac US - Stroke Volume Estimation with VTI
Cardiac output (CO) is defined as stroke volume (SV) multiplied by heart rate (HR).
On ultrasound, the measurement of SV can be obtained by multiplying the cross sectional area of the left ventricular outflow tract (LVOT) by the velocity time integral (VTI), which is an estimate of dynamic flow over the aortic valve over one heartbeat.
To obtain SV, you first measure the LVOT diameter on a parasternal long axis view of the heart combined with a pulse wave doppler VTI measurement at the LVOT in an apical 5 chamber view. A good waveform on VTI will show a property called “spectral clearing” where the inside of the wave is darker; this is representative of laminar flow. If you get opacification of the inner portion of your waveform, that may be representative of improper pulse wave gate positioning or turbulent flow. You can then plug the data into the US or into an online calculator.
Although the accuracy of the measurements of SV is questionable, the measurements can be used to guide resuscitation by performing a fluid challenge with 500cc of fluid or with straight leg raise. If the SV measured by ultrasound increases by 15% after a volume challenge/straight leg raise, the patient is defined as “fluid responsive” and can be given volume to assist with condition. If there is no response, the patient might require inotrope/vasopressor support to treat ongoing shock.
Cardiac US - Diastology
A normal ejection fraction on an echocardiogram does not exclude heart failure. You must be judicious with fluid administration in diastolic heart failure patients, similar to those with systolic heart failure.
Diastolic function is dependent on two factors: relaxation and compliance. Relaxation is the ability of the myocardium to relax during diastole and compliance is the ability for the myocardium to stretch during diastole.
Estimation of diastolic function can be performed on ultrasound using mitral valve inflow velocities and tissue doppler.
To obtain mitral inflow velocities, place a pulse wave doppler gate 90 degrees to the direction of flow in an apical four chamber view. The waveform you obtain will demonstrate an E wave that is representative of passive filling of the left ventricle during diastole and an A wave representative of the atrial kick for the last portion of filling of the LV. Normal patients have an E wave that is greater than A wave with a ratio >1. As patient’s relaxation/compliance diminishes, the A wave initially becomes greater due to increased reliance on the atrial kick for filling. With further diastolic heart failure, the left atrium dilates leading to weaker atrial kicks and reversal of the waveform, with the E wave greater than the A wave.
Tissue doppler measures the relaxation velocity of the left ventricular myocardium during diastole. This is obtained by placing a pulse wave doppler over the lateral or medial aspect of the mitral valve annulus and plotting out waves referred to as E’ and A’. If E/E’ velocity ratio is >15, that is indicative of the LVEDP being greater than 15 and volume overload. If the E/E’ ratio is <8, that is indicative of the LVEDP being less than 8 indicative of normo- or hypovolemia.
