UMEM Educational Pearls

How to set the correct PEEP remains one of the most controversial topics in critical care.  In fact, just on UMEM Pearls there are 55 hits when one searches for PEEP, including this relatively recent pearl on PEEP Titration.  

A recent Systematic Review and Network Meta-Analysis looked at existing trials on this issue.  They found that:

1) Higher PEEP strategies were associated with a mortality benefit compared to lower PEEP strategies

2) Lung Recruitment Maneuvers were associated with worse mortality in a dose (length of time of the maneuver) dependent fashion.

This fits with recent literature and trends in critical care and bolsters the feeling many intensivists are increasingly having that we may be under-utilizing PEEP in the average patient.  

Bottom Line: As an extremely broad generalization, we would probably benefit the average patient by favoring higher PEEP strategies, and avoiding lung recruitment maneuvers.  Do keep in mind that it is probably best to continue lower PEEP strategies in patient populations at high risk of negative effects of PEEP (e.g. COPD/asthma, right heart failure, volume depleted with hemodynamic instability, bronchopleural fistula) until these groups are specifically studied.

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The knee is one of the most commonly affected joints from osteoarthritis (OA).

Patients will complain of knee pain, swelling and stiffness.

This leads to disability as it interferes with walking, using stairs at home and getting in and out of chairs and the bath without assistance.

Increasing incidence due to aging of the general population and rising rates of obesity.

Patients frequently present to the ED for knee pain and imaging is often obtained.

Diagnosis of knee OA can be made with an appropriate history and imaging that shows osteophytes and joint space narrowing.

The best views for knee OA include 1) PA weight-bearing & 2) 45 degree of knee flexion

https://d3i71xaburhd42.cloudfront.net/6f8ce215fb4bcd153a478187c9a6a2ae652a5fc4/250px/1-FigureI-1.png

Note: Weight-bearing radiographs will demonstrate greater joint space narrowing than non-weight-bearing radiographs

Of the 3 compartments of the knee, the medial tibiofemoral compartment is most commonly affected > patellofemoral compartment > lateral tibiofemoral compartment.

Examples of knee OA

https://roberthowells.com.au/wp-content/uploads/2016/04/A00212F02.jpg

https://orthoinfo.aaos.org/link/e7e6933819db4020bc2f3822c45c538f.aspx

Hyperglycemic Hyperosmolar State (HHS)

• Though less common, HHS has a mortality rate that is 10x greater than DKA.
• The hallmark features of HHS include severe hyperglycemia (> 600 mg/dL), hyperosmolality (> 320 mOsm/kg), minimal to no ketosis, and severe dehydration.
• Though the management of HHS is similar to DKA and includes fluid resuscitation, correction of hyperglycemia, and correction of electrolyte abnormalities, it is important to also monitor serum osmolality.
• Too rapid correction of serum osmolality can cause cerebral edema and worsen patient outcomes.
• Current recommendations are to monitor serum osmolality every 1-2 hours with a correction of no more than 3 mOsm/kg/hr.

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Question

23 y/o otherwise healthy Male presents for approx. 3 month history of Right  leg mass. It is painful with activity (deep and sharp) but not enlarging. Patient remembers a fall from a bicycle 6 months ago, with negative imaging for fracture.

What is the diagnosis?

https://plinthsandplatforms.files.wordpress.com/2016/06/screen-shot-2016-06-20-at-10-58-18-am.png

https://radsource.us/wp-content/uploads/2019/02/1E.jpg

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The debate is still going on: Whether we should give balanced fluids or normal saline.  

Settings: PLUS study involving 53 ICUs in Australia and New Zealand. This was a double-blinded Randomized Control trial.

• Patients: A total of 5037 adults who were admitted to any ICU.
• Intervention: Balanced multielectrolyte solutions (BMES). Once patient is outside the ICU, the type of fluid was decided by the treating physicians.
• Comparison: Normal saline
• Outcome: 90-day all cause mortality.

Study Results:

• Patient characteristics:
  • 2515 patients in BMES group vs. 2522 in Saline group.  Characteristics were similar in both groups.
  • Median fluid amount = 3.9L (BMES group) vs. 3.7L (Saline group).
• Primary outcome:
  • Mortality = 21.8% (BMES group) vs. 22.0 (Saline), (OR 0.99, 95% CI 0.86-1.14)
• Secondary outcomes:
  • Requiring Dialysis: OR 0.98 (95% CI 0.83-1.16)
  • Requiring vasopressor: OR 0.92 (95% CI 0.78-1.09)
  • Maximum creatinine level: similar between groups (155.5 umol/L for BMES vs. 154.5 umol/L for Saline group)

Discussion:

• Treatment with saline increased serum chloride, and lower pH than BMES, but kidney function was not affected.

• An updated meta-analysis including this trial was also published in January 2022. This updated meta-analysis showed that the risk ratio for 90-day mortality for BMES was 0.96 (95% CI 0.91-1.01).  This data suggested that using BMES could reduce risk of death (up to 9%) or increase risk of death (up to 1%).
• Appropriate volume resuscitation is still more important than the type of fluid.

Conclusion:

• BME treatment was not associated with improved mortality.

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Background:

Multisystem inflammatory syndrome in children (MIS-C) as defined by CDC Health Advisory in May 2020 is:

1) An individual aged <21 years presenting with fever*, laboratory evidence of inflammation**, and evidence of clinically severe illness requiring hospitalization, with multisystem (>2) organ involvement (cardiac, renal, respiratory, hematologic, gastrointestinal, dermatologic or neurological); AND

2) No alternative plausible diagnoses; AND

3) Positive for current or recent SARS-CoV-2 infection by RT-PCR, serology, or antigen test; or exposure to a suspected or confirmed COVID-19 case within the 4 weeks prior to the onset of symptoms.

*Fever >38.0°C for ≥24 hours, or report of subjective fever lasting ≥24 hours

**Including, but not limited to, one or more of the following: an elevated C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), fibrinogen, procalcitonin, d-dimer, ferritin, lactic acid dehydrogenase (LDH), or interleukin 6 (IL-6), elevated neutrophils, reduced lymphocytes and low albumin

As of January 31^st, 2022 the CDC reports the following statistics related to MIS-C in the United States:

·         Total MIS-C patients meeting case definition= 6,851

·         Total MIS-C deaths meeting case definition = 59

·         The median age of patients with MIS-C was 9 years. Half of children with MIS-C were between the ages of 5 and 13 years.

·         59% of the reported patients with race/ethnicity information available occurred in children who are Hispanic/Latino (1,746 patients) or Black, Non-Hispanic (2,050 patients).

·         98% of patients had a positive test result for SARS CoV-2, the virus that causes COVID-19. The remaining 2% of patients had contact with someone with COVID-19.

·         60% of reported patients were male.

Management:

First-Line Treatment:

·         IVIG 2 g/kg dosed based on ideal body weight with a maximum of 100 grams (1000 mL)  

o   For patients with significant myocardial dysfunction and concern for fluid overload, the infusion can be given in divided doses over 2 days (1g/kg q12 x 2 doses)

PLUS

·         Methylprednisolone 1 mg/kg (max of 30 mg/dose) IV twice daily and switch to PO and taper when clinically appropriate

Upon Consultation with Pediatric Hematology/Cardiology will consider adding the following therapies to IVIG and steroids:

·         Enoxaparin treatment versus prophylactic dosing depending on D-dimer elevation and whether or not being admitted to PICU

·         Aspirin 3-5 mg/kg (max 81 mg/dose) daily unless platelet count < 80 K/mcl

Second-Line Treatment (refractory to IVIG defined by symptoms and fever persisting >36 hours)*:

·         Methylprednisolone pulse dosing- 30 mg/kg (max of 1000 mg/dose) x 3-5 days

OR

·         High dose anakinra

OR

·         Infliximab 5-10 mg/kg IV x1  

*All second-line treatment options require peds infectious diseases and PICU attending approval

UMMS COVID/MIS-C Pathway: https://intra.umms.org/-/media/intranets/umms/pdfs/dept/pharmacy-and-therapeutics/guidelines/umms-pediatric-covid-pathway.pdf?upd=20220125144550

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Acute facial palsy is common in children and while bell’s palsy is significant proportion, there are other more concerning etiologies that make up a number of cases. A retrospective cohort study of pediatric patients with an ED diagnosis of Bell’s palsy was done using the Pediatric Health Information System and showed an incidence of 0.3% (0.03% in control) for new diagnosis of malignancy within the 60 days following the visit at which bell’s palsy was diagnosed. Younger age increased the risk. There was also a subset of patient’s excluded for diagnosis of bell’s palsy as well as malignancy at the index visit.

These numbers are small but may be clinically significant. They likely do not warrant laboratory or imaging workup as a rule but do make a case for detailed history taking and thorough exam. Consider avoiding steroids which are used commonly but lack high quality data and may undermine later efforts at tissue diagnosis of malignancy or even worsen prognosis.

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A prospective, randomized, open-label, parallel assignment, single-center clinical trial performed by an anesthesiology-based Airway Team under emergent circumstances at UT Southwestern.

801 critically ill patients requiring emergency intubation were randomly assigned 1:1 at the time of intubation using standard RSI  doses of etomidate and ketamine.

Primary endpoint: 7-day survival, was statistically and clinically significantly lower in the etomidate group compared with ketamine 77.3% (90/396) vs 85.1% (59/395); NNH = 13.

Secondary endpoints: 28-day survival rate was not statistically or clinically different for etomidate vs ketamine groups was no longer statistically different: 64.1% (142/396) vs 66.8% (131/395). Duration of mechanical ventilation, ICU LOS, use and duration of vasopressor, daily SOFA for 96 hours, adrenal insufficiency not significant.

Other considerations:

1. Similar to a 2009 study, ketamine group had lower blood pressure after RSI, but was not statistically significant. 2

2. Etomidate inhibits 11-beta hydroxylase in the adrenals. Associated with positive ACTH test and high SOFA scores, but not increased mortality.2

3. Ketamine raises ICP… just kidding.

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Quadriceps contusion

Mechanism:  Blunt trauma from ball, helmet, stick

Usually to the central region

Damage to highly vascular area of the muscle and to local blood vessels can cause hematoma formation

Typical trauma history and pain worse with muscle activation (knee flexion)

Physical exam:  Bruising, tenderness, palpable mass/hematoma

Goals of care: Minimize intramuscular bleeding

Treatment:  NSAIDS, crutches, unique type of immobilization 

Attempt to increase resting length of the quadriceps muscle to facilitate early healing and return to function

• Immediately immobilize the affected leg in 120°of flexion with an elastic wrap x 24 hr
• https://img.medscapestatic.com/pi/meds/ckb/18/43218.jpg
• Frequent icing
• Followed by early stretching/ROM (Consider referral for formal PT)
• Continue restricted weight bearing on crutches as needed

Note:  Left untreated, large contusions may result in myositis ossificans

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Clinical pearls for hypothermic cardiac arrest

• VA-ECMO is rewarming strategy of choice – consider transport/contacting nearest ECMO center whenever possible
  • HOPE score predicts survival probability after ECLS rewarming and may guide ECLS decision making. Predictors include age, sex, mechanism of hypothermia, CPR duration, potassium, and core temperature at admission
• If access to ECMO center is not available, use external and internal rewarming strategies: removing wet clothes, forced-air heating blankets, warmed IV fluids (38-42C), thoracic and/or peritoneal lavage
• High-quality continuous CPR is key. Use mechanical CPR when available
• Lack of consensus with regards to ACLS guidelines. European Resuscitation Council recommends up to 3 attempts at defibrillation and withholding epinephrine while core temp is < 30C. AHA states reasonable to follow standard ACLS algorithms. It has been suggested that administering up to 3 shocks and 3 doses of epinephrine while core temp is <30 C is a reasonable approach, with additional doses guided by clinical response
• Resuscitate until core temp is at least 32C (warm and dead). Once rewarmed, consider termination of resuscitation with persistent asystole or K >12

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Background: Conventional medical wisdom long held that patients with pneumothorax (PTX) who require positive pressure ventilation (PPV) should undergo tube thoracostomy to prevent enlarging or tension pneumothorax, even if otherwise they would be managed expectantly.¹

• Small retrospective and observational studies have demonstrated safety to an observational approach for both occult (only detectable on CT) and larger PTXs even in patients requiring noninvasive or invasive mechanical ventilation, whether traumatic/iatrogenic or spontaneous.^2-6
• The Western Trauma Association recently released a guideline for the management of traumatic PTX, which includes observation with 6-hour follow up CXR for patients with small (<20% aka <2cm from chest wall on CXR or <35 mm on CT scan) hemodynamically stable pneumothoraces, even if mechanical ventilation is required.⁷
  • They note a 10% subsequent failure rate (i.e. chest tube requirement) with no difference between patients who do or do not undergo PPV. 
• The OPTICC trial, found however, that while the rate of respiratory distress development was not different between those randomized to observation vs initial chest tube management, there was an increase from a 25% chest tube requirement in the obs group to a 40% failure rate in patients requiring >4 days of mechanical ventilation.⁸ 

Bottom Line: The cardiopulmonar-ily stable patient with small PTX doesn’t need empiric tube thoracostomy simply because they’re receiving positive pressure ventilation. If you are unlucky enough to still have them in your ED at day 5 in these COVID times, provide closer monitoring as the observation failure rate may increase dramatically around this time.

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Flumazenil is a reversal agent for benzodiazepine overdose.  Adverse events including seizure, agitation and cardiac arrhythmias have been reported but the frequency of adverse events is unknown.

AE and serious AEs were defined as:

AE: 

• Aggressive behavior, agitation, screaming, restlessness
• Nausea/vomiting, abdominal cramps
• Sweating, shivering, chills, hot flashes
• Headache, dizziness
• Anxiety, distress, depressed mood, abnormal crying
• Tremors 

Serious AE (SAE):

• Seizures
• Supraventricular arrhythmia
• Multiple ventricular beats
• Tachycardia
• Sudden fall in systolic BP

A systematic review/meta-analyses of 13 randomized controlled trials showed

• AEs more common in flumazenil group vs. placebo (risk ratio: 2.85; 95% CI: 2.11-3.84)
• SAEs more common in flumazenil group vs. placebo (risk ratio: 3.81; 95% CI: 1.28-11.39) 

Most common AEs

• Aggressive behavior, agitation, screaming: 26.2% (n=33/126)
• Nausea/vomiting, abdominal cramps: 20.6% (n=26/126)
• Anxiety, distress, depressed mood: 15.7% (n=19/126)

Most common SAEs

• Supraventricular arrhythmia: 30% (n=4/12)
• Seizure: 25% (n=3/12)
• Tachycardia: 25% (n=3/12)

Conclusion

• Administration of flumazenil to patients with known or suspected benzodiazepine overdose is associated with increased risk of AEs

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Hamstring Injury

Prevalence varies by sport ranging from 8 to 25 percent with a high recurrence rate frequently during the ensuing sport season, usually in next 2 months but may extend up to one year!

Highest in sports that involve rapid acceleration and deceleration

            3 highest risk sports - football and men’s and women’s soccer

Average time lost 17-21 days

Injury much less common in younger athletes

The hamstring is composed of three muscles: the biceps femoris, semitendinosus, and semimembranosus.

Primarily involved in knee flexion and hip extension

Biceps femoris is most commonly injured

https://www.ncbi.nlm.nih.gov/books/NBK539862/figure/article-28873.image.f1

Simple grading system using 3 grades

Grade 1 – mild strain

Grade 2 – Partial tear

Grade 3 – Complete tear

Proximal injuries are more common than distal injuries, occurring at the musculotendinous junction

Avulsion fractures of the ischium occur rarely occur in adults but may occur in skeletally immature athletes

https://radiopaedia.org/cases/ischial-tuberosity-avulsion

When watching a sporting event you will see the athlete grab the buttock or upper thigh. They usually cannot return to play. Most grade 2 or 3 injuries will require crutches. If seeing them the following day significant bruising may be seen.

Numerous modifiable and non-modifiable risk factors have been identified including:

*Weakness of ipsilateral quadriceps or contralateral hamstring, hamstring, hip & quadriceps tightness/poor flexibility, poor warm-up, sudden increased training volume and muscle fatigue.

*Older age (risk increase may begin as early as age 23)

Prior hamstring injury (up to 6x increased risk)

            **Premature return to sport increases the risk of reinjury

Differential Diagnosis:  Lumbar radiculopathy, sciatic nerve irritation or compression, stress fracture of femur.

Refer to sports medicine/orthopedics for avulsion injuries, complete proximal complete tears and partial or complete distal tears

Many types of foreign bodies may be found in a child's ear. Some examples include: beads, cotton swabs, food, insects, and button batteries. 

Patients can be asymptomatic. However, they often have otalgia, pruritus, fullness, tinnitus, hearing loss, otorrhea, or bleeding. Obtain a history of the type of foreign body, when/how it entered the ear, and if there was a prior attempt at removal. Also ask if there are foreign bodies elsewhere, such as in the nose. Perform Rinne and Weber tests before and after removing the foreign body if the child is old enough to participate. 

Delayed presentation can result in edema and otitis externa. When the foreign body is sharp, there may be damage to the tympanic membrane (TM) and ossicles. 

Consult ENT when there is suspicion of damage to TM, when hearing loss is present, or when removal is especially challenging. Spherical foreign bodies are more difficult to remove. 

Remove foreign body if it can be visualized. Wax curettes, right-angled hooks, alligator forceps, and Frazier tip suctions can facilitate removal. Avoid additional trauma due to concern for edema, bleeding, TM perforation, or distal displacement of the object. Anxiety in the child will lead to increased difficulty with removal. 

A button battery in the ear is an emergency that can result in severe damage, including TM perforation, scarring or stenosis of the ear canal, and deeper injury. Seeds such as beans or peas and other absorptive material in the ear can expand, so do not irrigate when such foreign bodies are present. Living insects should be killed with alcohol, lidocaine, or mineral oil prior to performing foreign body removal. 

After removal, reassess ear canal and TM. Some foreign bodies require removal in the operating room. If the object has been successfully removed, evaluate for otitis externa or iatrogenic injury to the ear canal, and prescribe antibiotic otic drops when needed. When TM has perforated, refer for formal audiogram. ENT follow up is recommended for all patients.  

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   There are several well known medications that we tend to give by default during cardiac arrests.  It seems like for each of them, every few years someone does an RCT to see if they really help anybody, and we're all disappointed by what they find.  Well... prepare to be disappointed again, I'm afraid.

   These Danish authors randomized 391 patients in cardiac arrest to either calcium or saline (given IV or IO).  They gave 2 doses of either calcium chloride or saline, with the first dose being along with the first epi dose.  Primary outcome was ROSC.  They also looked at modified Rankin at 30 and 90 days.

  The trial was stopped early for harm.  Now, we all know the dangers of interpreting studies that were stopped early, but this doesn't look great for calcium.  19% of the calcium group had ROSC compared to 27% of the saline group (p = 0.09).  Percentage of patients alive, and with favorable mRS at 30 days also both favored the saline group (although also not statistically significantly).  By the way, of the patients who had calcium levels sent, 74% in the calcium group, vs 2% in the saline group, were hypercalcemic.  Whether that had anything to do with the outcome, we may never know.

Bottom Line:  Is this saying that calcium hurts patients in cardiac arrest?  Maybe... but I don't think this is high quality enough data to draw that conclusion.  At the very least, however, just giving everyone in arrest calcium is probably not terribly helpful.  If you have a reason to give it (known severe hypocalcemia, recent parathyroid surgery, suspected hyperkalemia, etc) then go for it, otherwise you can probably focus your resus on more important things.

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• Pediatric acute gastroenteritis has always been a major cause of ED visits and hospitalizations.
• Pediatric complaints of vomiting and diarrhea have been on the rise, whether it be secondary to the new Omicron-variant of COVID-19, or norovirus and rotavirus which traditionally account for nearly 60% of all cases.
• Zofran (Ondansteron) 4mg for children 4-11yo weighing greater than 40kg, and up to 8mg for those older.
• Zofran prescription at discharge was associated with reduced rate of return at 72-hours and was not associated with masking alternative diagnosis like appendicitis and intussusception.
• Oral rehydration therapy (ORT) consisting of a low osmolarity solution containing sugar and salts along with zinc has also been shown to optimize treatment and diminish return visits. ORT is available in commercial packets, pre-mixed solutions, or can be made at home with table salt and sugar.
• Bottom Line: Consider providing a prescription of Zofran along with recommendations for oral rehydration therapy consisting of a low osmolarity solution containing sugar and salts to prevent outpatient treatment failure and return visits.

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The BOUGIE Trial

• More than 1 million patients undergo endotracheal intubation each year in the US.
• Up to 20% of intubations fail on the first attempt, thereby increasing the risk of adverse outcome.
• Over the past several years, many have become comfortable using the bougie as a rescue device when the first attempt at intubation fails with an endotracheal tube with stylet.
• In contrast to its use as a rescue device, should the bougie be used during the first attempt rather than an endotracheal tube with a malleable stylet?
• The BOUGIE Trial compared the effect of using the bougie to an endotracheal tube with stylet on first attempt success in critically ill patients.
• The trial enrolled 1106 patients in 7 EDs and 8 ICUs at 11 hospitals.
• The primary outcome of first pass success was not statistically different between those randomized to bougie and those randomized to endotracheal tube with stylet for the first attempt at intubation.. 
• Though the trial did not find a statistical difference in first pass success rates, the bougie remains an important device in our management of the critically ill airway.

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Caffeine is probably the most wildly used and studied drug/supplement in the world.

It has been shown to enhance exercise capacity and performance.

Mechanism of action is likely multifactorial and involves adenosine receptor antagonism via direct CNS action improving mental alertness, reaction time and reducing the perceived exertion rate (pain).

To no surprise, amateur and elite athletes use caffeine to improve performance.

The well-accepted dosage of caffeine to improve performance is between 3 and 6 mg/kg, approximately 60 min before exercise. This dosage promotes (between 1 and 8%) performance gains in aerobic exercises and exercises with high glycolytic demand from cyclists to tennis players to weightlifters.

Consider the lower end of this range if interested in trying this on your own.

In an evaluation of 20,686 urine samples of elite athletes, almost 75% of the samples contained caffeine in concentrations higher than 0.1 μg/mL

Caffeine also increases maximal oxygen uptake (VO2 max)

23 elite athletes were tested twice with and twice without caffeine.

Randomized, double-blinded, placebo-controlled study.

Caffeine 4.5 mg/kg taken 45 minutes before exercise

Measures: Time to exhaustion and VO2 max.

Caffeine increased time to exhaustion and VO2 max, thereby increasing overall performance.

If you are going to incorporate using caffeine before your next workout, I suggest espresso shots for extra caffeine without the volume of a large cup of coffee. Beware of known side effects such as jitters, anxiousness and difficulties with sleep if taken later in the day. Also consider stomach upset digestive issues, and increased heart rate.

Happy Holidays!!!!

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