Inhaled toxins frequently cause asphyxiation and can be classified further as chemical asphyxiants, simple asphyxiants, and pulmonary irritants.  

Chemical Asphyxiants include Hydrogen Sulfide and cyanide. Hydrogen sulfide typically presents with a sulfur-like smell, while cyanide is typically presented in the burning of plastics. 

Simple Asphyxiants are anything which replaces oxygen in the atmosphere, including carbon monoxide or dioxide, methane, helium, or nitrogen. These may be present in a mine or other industrial setting, and may classically present as an unconscious worker who was attempting to rescue another unconscious worker. 

Irritant gases cause pulmonary irritation from coughing to diffuse lung injury. Irritants are categorized by their solubility; highly soluble irritants typically have strong scents because they are easily mixed into the upper airway, while less soluble irritants are typically less rapid in onset and will result in lower airway complaints. 

• High Solubility: Rapid onset of symptoms and upper airway symptoms due to increased solubility. Will have strong scent. These include ammonia, formaldehyde, sulfuric acid, and chloramines.
• Intermediate Solubility: Chlorines & hydrogen sulfides. Slight delay in presentation
• Poorly Soluble: Perfluororisobutylene (PFIB) from burning plastics, phosgene. Delayed presentation and severe lower airway irritation. 

Utilization of blood cultures can assist the treatment of many patients, however not every patient requires blood cultures. Whenever drawn, you should obtain two sets of cultures (or 3 for endocarditis). A recent article found a number needed to treat was 250 for a change in treatment, however other studies have found blood cultures more useful.

Major Criteria:

• temperature > 39.5°C (103.0°F)
  
• indwelling vascular catheter
  
• clinical suspicion of endocarditis
  

Minor criteria

• temperature 38.3–39.4°C (101– 102.9°F)
  
• age > 65 years
  
• chills
  
• vomiting
  
• hypotension (systolic blood pressure < 90 mm Hg)
  
• neutrophil% > 80
  
• white blood cell count > 18 k
  
• bands > 5%
  
• platelets < 150 k
  
• creatinine > 2.0.
  

​www.sciencedirect.com/science/article/pii/S0736467908004447?via%3DihubA blood culture is indicated by the rule if at least one major criterion or two minor criteria are present.

Patients with CURB 65 scores 0-1 can potentially be discharged, however consider the patient's physical exam, oxygen saturation, and immunosupressed status, as the CURB 65 score does not take these into account. Those with a CURB 65 score greater than 3 should be considered for an ICU admission. 

The PSI/PORT score can also be used but is more thorough, including nursing home status, liver and heart disease status, as well as ABG data. While the CURB 65 has better specificity for identifying severe disease, the PSI/PORT score is more sensitive at identifying low-risk patients for discharge.

For CAP, guidelines recommend Azithromycin or Doxycycline as azythromycin has increasing rates of resistance. In outpatients with co-morbidities or risk for resistance, you should consider levofloxacin or moxifloxacin. Patients admitted for CAP should be treated with single agent fluoroquinolone or dual agent treatment with ceftriaxone and azithromycin. ICU admitted CAP patients require an anti-pneumococcal betalactam (Ceftriaxone) and either azithromycin or fluoroquinolone. Treatment duration is typically 5 days. 

In patients with severe hypoxia and shortness of breath, consider NIPPV early, even before CT diagnosis. As the patient has increased Right sided failure and RV dilation, the patient will continue to have worsening RV ischemia and decreased RV contractility. As RV afterload increases you begin having worsening right sided failure and worsening cardiac output. In patients who require inotropes, consider norepi and dobutamine. 

• Early NIPPV and correction of hypoxia to prevent pulmonary vasoconstriction
• Decreased IV Crystaloid to prevent increased afterload and worsening RV function
• Norepi for patients requiring inotropic support. 

The use of systemic thrombolytics are supported by most protocols. Many RTCs have evaluated the use of thrombolytics, including half-dose and catheter-directed TPA. While mortality improves with thromolytic use in massive PEs, RTCs evaluating lytics in submassive PEs have been mixed. Catheter-directed intervention is a safe and effective treatment for both submassive and massive PEs.