Author: Sam Killian, MD
- Being exposed to E-cigarette vapor may increase risk of pneumonia.
- Recent study has shown e-cigarette vapor increases quantities of Platelet-activating-receptor factor in epithelial cells, which may aid pneumococcal bacteria in entering pneumocytes.
Miyashita L, et al. (2018). E-cigarette vapour enhances pneumococcal adherence to airway epithelial cells. The European Respiratory Journal. 7;51(2).
Author: Don Stader, M.D.
- Pulmonary embolism is one of the leading causes of maternal mortality.
- There is disagreement among different medical societies about the value of D-dimer as a screening modality. If you use it, consider the rational D-dimer approach whereby you add 250 to your cut-off for every trimester.
- A useful screening modality is an ultrasound of bilateral lower extremities looking for DVT.
- Keep in mind, both a V/Q scan and CT scan have a significant amount of radiation. CTA is probably the right diagnostic test (less radiation than CT w&w/o).
- Always use the shared decision-making model and clinical acumen to choose your tests.
Leung AN, et. al. (2011). An official American Thoracic Society/Society of Thoracic Radiology clinical practice guideline: evaluation of suspected pulmonary embolism in pregnancy. American Journal of Respiratory and Critical Care Medicine. 184(10):1200-8
Polak JF, Wilkinson DL. (1991). Ultrasonographic diagnosis of symptomatic deep venous thrombosis in pregnancy. American Journal of Obstetrics and Gynecology. 165(3):625-9.
Sachs BP, et. al. (1987). Maternal mortality in Massachusetts. Trends and prevention. New England Journal of Medicine. 316(11):667-72.
Check out this episode!
Author: Sam Killian, M.D.
- Difficulty with bag valve mask (BVM) ventilation can be addressed using the MOANS mnemonic.
- Mask seal, Obesity/obstruction, Age, No teeth, Sleep apnea.
- Often BVM difficulty can be addressed by an extra set of hands.
Author: Dave Rosenberg, M.D.
- Poiseuille’s Law addresses the flow of a fluid through a tube.
- Many common ED presentations involve alterations in flow: asthma, MI, ischemic stroke, etc.
- According to the law, flow increases with the 4th power of the radius. That is to say, doubling the radius of the tube will increase the flow by 16x.
- Therefore, in situations that require re-opening of an anatomic tube (artery, airway), small changes in the size of the opening will result in dramatic effects.
Author: Julian Orenstein, M.D.
- Colorado has a high population of unvaccinated children, and is at increased risk for pertussis outbreaks.
- The causative organism is Bordetella pertussis. It causes causes respiratory epithelial necrosis leading to congestion of the bronchioles, leading to cough.
- The cough is unique – it is usually a series of expiratory coughs followed by one deep inspiration
- The clinical presentation is divided into 3 phases:
- Catarrhal: cough and congestion with low-grade fever and coryza.
- Whooping: characteristic cough.
- Resolution: recovery with persistent cough.
- Infants may not get this presentation, but may get apnea and nonspecific cough.
- Tongue depressor can be used to elicit cough for diagnosis.
References: Tozzi AE, Pastore Celentano L, Ciofi degli Atti ML, Salmaso S. Diagnosis and management of pertussis. CMAJ?: Canadian Medical Association Journal. 2005;172(4):509-515. doi:10.1503/cmaj.1040766.
Author: David Rosenberg, M.D.
- Preoxygenation is done before rapid sequence intubation, and should be done even if SaO2 is at 100%.
- Preoxygenation is done to fill the lungs with oxygen rather than ambient air, which is only 20% O2. While the patient is paralyzed, the O2-filled lungs will continue to oxygenate venous blood, buying you more time for intubation.
- BiPAP is an effective tool for pre-oxygenation.
Author: Michael Hunt, M.D.
- In the recent YEARS study, investigators checked every patient with suspicion for PE with a D-dimer, using a modified Wells score for risk stratification. The goal of the study was to show that CT scan usage could safely reduced using this screening method.
- The Wells Criteria measures they used to stratify risk were: PE mostly likely dx, hemoptysis, and evidence of DVT. If the d-dimer was 1, but the patient had none of the Wells criteria, the patient did not get a CT. If the patient had any of the criteria, but the d-dimer was only 0.5, the patient did not get a CT scan.
- The investigators reduced CT usage by 14% using the new criteria, with no significant increase in morbidity and mortality.
References: van der Hulle et al. Simplified diagnostic management of suspected pulmonary embolism (the YEARS study): a prospective, multicentre, cohort study. The Lancet. 2017
Author: Jared Scott, M.D.
- The foramen ovale (FO) connects the left and right atria to allow oxygenated blood to bypass the developing lungs, it usually closes at birth but for some it remains patent (PFO).
- A PFO allows clots to cross from the venous to arterial circulation, increasing the likelihood of stroke.
- PFO is present in 25% of general population, present in 50% of those with stroke of unknown cause, and very common those with stroke under 50 years old.
- Treat with anticoagulation or surgical correction.
Author: Gretchen Hinson, M.D.
- High-Altitude Pulmonary Edema (HAPE) is caused when hypoxemia due to low ambient pO2 leads to breakdown and constriction of the pulmonary vasculature leading to edema.
- HAPE is very rare under 8000 ft, but common over 10000 ft (6%). Over 18,000 ft the incidence is very high (12-15%).
- Symptoms include dyspnea, cough, weakness and chest tightness.
- Signs include hypoxemia, crackles, wheezing, central cyanosis, tachypnea and tachycardia.
- Drugs that reduce pulmonary resistance have been shown to help, but increased oxygenation and descent are the best treatments.
Author: Michael Hunt, M.D.
- Wells Criteria was initially designed to screen patients for further workup for PE.
- Aspects of the Wells Criteria include: signs and symptoms of DVT (3 points), PE most likely dia (3 points), HR > 100 (1.5 points), immobility for > 3 days or surgery in last 4 weeks (1.5 points), documented history of PE (1.5), hemoptysis (1), treatment for cancer in last 6 mo (1).
- ACEP uses a score of less than or equal to 4 to define “low risk.” Greater than 4 is “high risk”.
- Use Wells to guide clinical decisions about PE workup.