Nitroglycerin easily migrates into polyvinyl chloride (PVC), a plastic commonly used in intravenous tubing due to its flexibility and low cost. A slow rate of flow and long tubing length increase the loss of nitroglycerin. While using less absorptive tubing (i.e. polyethylene or polypropylene) when administering nitroglycerin is recommended, most published clinical studies looking at nitroglycerin have used PVC tubing.
A 1989 study compared nitroglycerin delivery through PVC tubing and low sorbing tubing at various concentrations and flow rates.1 Samples were obtained from the nitroglycerin bottle and the distal end of the tubing at several time points.
A 2018 study enrolled 8 volunteers to receive nitroglycerin infusions through PVC tubing and low sorbing polyolefin tubing.2
Bottom Line: Most studies evaluating nitroglycerin use in various clinical scenarios have used PVC tubing. Doses based on use with PVC tubing may be too high when using less absorptive tubing. Employing more conservative dosing strategies when using low sorbing tubing can help mitigate the risk of adverse effects (i.e. hypotension, headache).
Prophylactic antibiotic use in cirrhotic patients with an upper GI bleed has been demonstrated to have a mortality benefit in multiple randomized clinical trials. Some trials as well demonstrated a decreased risk of rebleeding as well as a shorter hospital length of stay (1,2).
The exact means of protection is not entirely clear and its benefit is seen in both variceal and nonvariceal hemorrhages as well as in cirrhotic patient both with and without ascites.
There does appears to be a close interplay between cirrhosis bleeding risk and infection, with infection being a common precipitating factor for upper GI bleed.
The antibiotic of choice is ceftriaxone 1 gram IV daily for seven days. Although in case of allergy/intolerance, fluoroquinolones or aminoglycosides may be used as alternatives (3).
Bottom line:
All forms of upper GI hemorrhage in cirrhotic patients warrant prophylactic antibiotic use (regardless of the presence of ascites) as well as a diligent search and exclusion of possible infectious sources.
Pt presents to the emergency department with knee pain.
You decide to ultrasound the proximal knee. You place your ultrasound probe in the midline of the knee with your probe marker towards the patient's head.
What is the diagnosis?
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The answer is a quadriceps tendon rupture with femur fracture.
Bottom Line: Lack of pericardial fluid or cardiac motion on FAST exam leads to no intact survivors for ED RT for trauma.
Zone 1 REBOA may be as good or better than ED RT for those requiring aortic occlusion after trauma.
Intact neurologic survival after emergency department resuscitative thoracotomy (ED RT) for trauma is low. Best outcomes have been shown for stab wounds to the chest with loss of vital signs in the ED or just prior to ED arrival. Worst outcomes are for blunt trauma with loss of vital signs in the field.
Two studies help us further evaluate the use of emergency department resuscitative thoracotomy. Inaba et al. illustrate in patients undergoing a FAST exam prior to or concomitant with ED RT “The likelihood of survival if pericardial fluid and cardiac motion were both absent was zero.” Cralley et al. compared survival after ED RT to Resuscitative Endovascular Balloon Occlusion of the Artery (REBOA) zone 1 (above celiac axis) and found REBOA was as good or better when used in centers with experience with both procedures. They advocate for a randomized trial to compare the two procedures further.
The authors of this study retrospectively compared the 10-day mortality rates of patients who were triaged to levels 3-5 on the Scandinavian Rapid Emergency Triage and Treatment System (RETTS) during times of ED crowding (as measured by length of stay and percentage bed occupancy) with those who came to the ED at other times.
Patients were divided into four quartiles, corresponding with 2-hour length of stay blocks with quartile one having a length of stay of 2 or fewer hours and quartile four having a length of greater than 8 hours
Results: 705,076 patients were seen in one of two EDs from 2009 to 2016. The 10-day mortality rate was 0.09% (n = 623). The authors found an increased 10-day mortality for patients in quartile four as compared to those in quartile one “(adjusted odds ratio 5.86; 95% confidence interval [CI] 2.15 to 15.94)” This was also true for times when the ED occupancy ratio was greater than one (more than one patient in the ED per available bed). “Adjusted odds ratios for ED occupancy ratio quartiles 2, 3, and 4 versus quartile 1 were 1.48 (95% CI 1.14 to 1.92), 1.63 (95% CI 1.24 to 2.14), and 1.53 (95% CI 1.15 to 2.03), respectively”
Older patients and those with co-morbidities were at greatest risk but lower-acuity patients in all age and morbidity classes had an increased risk of death within 10 days if they came to the ED when it was crowded.
Some things are easy, even reflexive, and one of those things is putting oxygen on cyanotic patients. Usually, this is a great thing. Blue = bad. Occasionally, though, blue = baseline and even in those patients who are too blue, you want to keep them closer to purple than pink.
This issue is commonly encountered in certain types of congenital heart disease and as well as through various phases of their repair. These include ductal dependent lesions, those with significant shunts, and single ventricle physiology. Oxygen functions as a pulmonary vasodilator and can increase or change the direction of shunting, directly impacting physiology by causing pulmonary overcirculation, increased strain on the right ventricle, and decreases in systemic circulation.
Helpful Hints:
1) Find out and shoot for the patient’s goal oxygen saturation range (many lesions will be 75%-85%). This may be available from parents, in the EMR, or by calling the child’s cardiac center if they are an established patient.
2) In an undiagnosed neonate with hypoxia and signs of heart failure (crackles, enlarged liver, edema to the sacrum and/or occiput) or if unresponsive to initial trial of oxygen, decrease FiO2 and titrate support (nasal cannula with blender to set FiO2, HFNC, NIPPV, or intubation if necessary) to address respiratory distress as well as evaluation and treatment for ductal dependent lesions.
3) You may still need to use additional FiO2 to obtain reasonable oxygen saturations, but titrate thoughtfully.
Calcium channel blocker (CCB) overdose can lead to severe shock/hypotension. A small study was conducted to compare the hemodynamic effects of high-dose insulin (HDI) for two classes of CCB (dihydropyridines vs. non-dihydropyridines) that work differently to manage hypertension.
Study design:
Study sample:
Result
Median number of maximum concomitant vasopressors (p=0.04)
Median difference in max concomitant vasopressors: 1 (95% CI: 0 – 2)
Median max epinephrine dosing
Use of rescue methylene blue (p=0.009)
Conclusion:
A study looking at 177 trauma patients (predominately skiing injuries) treated with oral trans mucosal fentanyl (600 and 800 mcg dosing) found a statistically and clinically significant reduction in pain. This therapy could be an adjunct to patients who require pain relief but IV access is delayed for various reasons.
Background: In general practice, platelets are typically transfused for invasive procedures when the platelet count falls below 50 x 109/L. Regarding the placement of central venous catheters (CVCs), there is minimal data to support or refute decisions to transfuse platelets in these patients, although the 2015 Clinical Practice Guideline from the AABB (formerly, the American Association of Blood Banks) recommends deferring platelet transfusion until a platelet count of 20 x 109/L for CVC placement [weak recommendation, low quality evidence].1
In a study published this month in NEJM,2 van Baarle et al. performed a multicenter randomized controlled noninferiority trial comparing platelet transfusion to no transfusion in patients with platelets 10 to 50 x 109/L prior to US-guided CVC insertion. The primary outcome was the occurrence of catheter-related bleeding Grades 2-4 (Grade 1 = oozing; managed with <20 min of manual compression, not requiring RBC transfusion, & Grades 2-4 is everything else up to death) within 24 hours post-procedure.
Bottom Line: The jury is still out on best platelet transfusion practices prior to CVC placement, but I would strongly consider prophylactic platelet transfusion in patients with platelets < 30 x 109/L, those with underlying hematologic malignancy, and patients receiving larger CVCs such as dialysis lines. How much to transfuse in those with more severe thrombocytopenia is uncertain.
Separately, I would also strongly recommend use of US-guidance for any CVC placement in this population as well, based on practical common sense and some supportive literature as well.5
We hope that you enjoy your Memorial Day!
Don't forget your Sandy Beach Sign vs Barcode Sign of Lung Ultrasound:
Normal lung will have good pleural sliding. When you image the lung with M-Mode it looks like a Sandy Beach.
A lung with a pneumothorax will have poor lung sliding. When you image the lung with M-Mode it looks like a classic barcode or "stratosphere sign."
Make sure that you are on "Lung Mode" or decrease the gain to better image the movement of the pleural line. The negative predictive value for lung sliding on ultrasound is 99%. This means that if you see lung sliding you do not have a pneumothorax in that area. However, lung sliding is affected by certain conditions such as blebs, pulmonary fibrosis, pleural adhesions and right mainstem intubation. So, like any other radiology study, clinically correlate!
Thinking about placing a chest tube or have a patient with multiple rib fractures? Take a look at how to perform a Serratus Anteror Plane Block here: https://www.thepocusatlas.com/thoracoabdominal-blocks#Serratus
This study looked at 20 years of death by firearm and stratified the location of death from urban to rural. The authors concluded:
“Descriptively, in all county types and both decades of the study, per capita gun suicides were more common than per capita gun homicides, and the most rural counties had higher rates of firearm death compared with the most urban counties. Firearm death rates were meaningfully higher in 2011-2020 compared with 2001-2010, primarily because of an increase in gun suicides.”
Intersection syndrome
Intersection syndrome is an overuse injury of the forearm.
Pain is located approximately 2 finger breaths (4cm) proximal to the wrist joint.
https://www.sportsmedreview.com/wp-content/uploads/2020/11/intersectionsyndrome.png
Mechanism: friction is caused by repetitive wrist extension activities
Commonly: Rowing, skiing, tennis, canoeing and weightlifting
Friction may cause crepitus with finger/wrist extension.
Tenderness, mild swelling may be present
Clinician Well-Being and the Patient Experience
Did you know that most patient experience responses are overwhelmingly positive? Rather than focusing all our attention on the bad, let’s focus on the good to promote clinician well-being. See below for a few key points from a recent study on this:
Consider emphasizing positive patient experiences when providing feedback to emergency physicians. It will promote clinician well-being and help improve performance in your practice.
Ability to move the head and neck freely can be clutch in endotracheal intubation, so in patients such as certain trauma patients who may have c-spine instability and need to be immobilized, it's all the more important to choose the optimal intubation approach to maximize success and minimize head movement.
Choi et al recently published a study in Anesthesia looking at:
-Video laryngoscopy with a standard geometry Mac blade
vs
-Fiberoptic intubation
as the initial method for intubating patients in c-collars about to undergo spinal surgery. This is an interesting contrast between two extremes, as standard geometry is the most "traditional" approach, whereas fiberoptic is kind of the opposite end of the spectrum, jumping to a more advanced method which might be more flexible (no pun intended) but also introduces new complexities.
All outcomes actually favored standard geometry VL over fiberoptic, including first pass success (98% vs 91%), time to intubation (50s vs 81s) and need for additional airway maneuvers (18% vs 56%). There was no difference in complication rates, although a bigger study might be needed to find rare complications (this study had 330 patients).
In my opinion, it's unfortunate they didn't include hyperangulated VL, as it would be interesting to see how this approach compares. Personally I think of hyperangulated VL in these patients as a nice blend of the two methods, bringing the familiarity and speed of typical VL intubation, but often requiring less neck movement like fiberoptic.
Bottom Line: This study does not support a fiberoptic first approach to intubating patients with cervical spine instability. In fact, it may cause harm.
It is time to abandon the ABC's that ATLS teaches and move to hemorhage control (circulation) as well as resucitation before we deal with airway in the majority of trauma patients. Tounriquets save lives. Pelvic binders save lives. Blood transfusion (whole blood) saves lives. Poisitive presssure ventilation, sedativies, and decreasing sympathetic drive in hypoternsive patients makes their hypotension worse.
Please consider changing to a CAB approach to the hyhpotensive trauma patient.
Does IV contrast help to make the diagnosis in ED abdominal pain patients undergoing CT scan? The authors of this study tried to answer that question. This study was a retrospective diagnostic accuracy study looking at contrast enhanced vs. non-enhanced images in 201 consecutive ED patients. The study demographics were:
“There were 201 included patients (female, 108; male, 93) with a mean age of 50.1 (SD, 20.9) years and mean BMI of 25.5 (SD, 5.4).”
The study found: “Unenhanced CT was approximately 30% less accurate than contrast-enhanced CT for evaluating abdominal pain in the ED.”
This study is limited by the small size, the overwhelming female to male inclusion, the reliance on radiology reading as the gold standard of pathology, and the retrospective nature. It does, however, show that there is a need for further study and at this time giving IV contrast has limited down side and potentially improves diagnostic accuracy of abdominal CT scans.
Bicarbonate Use for Lactic Acidosis?
