Bedside Pearls: Pulmonary Hypertension

I recently took care of a critically ill patient with history of pulmonary hypertension who presented to the ED by EMS complaining of dyspnea and cough. There are many unique features and critical steps when caring for patients with pulmonary hypertension that I wanted to highlight here.

• First, we have to acknowledge that diagnosing pulmonary hypertension is often missed until late in the disease progression. Emergency physicians have to consider the possibility that the patient who presents with dyspnea has pulmonary hypertension in their differential diagnoses.
• In the setting of pulmonary hypertension, the right ventricle (RV) is impaired both mechanically and by ischemia. Increased RV pressure leads to bowing of the septum into the left ventricle (LV), which leads to decreased LV filling and decreased cardiac output. Increased RV pressure also leads to increased stretching of the RV wall causing tricuspid regurgitation, which in turn results in decreased cardiac output. Any decrease in cardiac output will result in impaired perfusion of the RV and worsening ischemia. This is the spiral of death.
• First step in management is to fix the underlying hypoxia and hypercapnia as they both result in increased pulmonary vasoconstriction. If at all possible, avoid intubating these patients as this can precipitate hemodynamic collapse and even cardiac arrest. Start with basic airway maneuvers or noninvasive positive pressure ventilation.
• Hypotension will result in worsening RV ischemia and, therefore, should be avoided. However, clinical assessment of volume status is very difficult in the setting of RV failure. We were all taught that the RV is preload dependent, but most RV failure in the setting of pulmonary hypertension will be associated with volume overload. A large fluid bolus may actually worsen hemodynamics by increasing RV stretch, septal bowing and decreased LV output. Start with low volume boluses (250-500 mL of crystalloid solution) and frequently reassess clinical response. 
• Start a vasopressor early. Norepinephrine is a good first choice. Consider adding Vasopressin if hypotension persists. Vasopressin may actually decrease pulmonary vascular resistance (PVR). Avoid Phenylephrine because it increases PVR.
• Look for and manage other precipitants of pulmonary hypertension, such as COPD, LV failure and pulmonary embolism.
• The EKG is your friend. Below are common EKG findings associated with pulmonary hypertension:
  • Right-axis deviation
  • Right bundle branch block
  • rSR’ in V1
  • qR V1
  • Large inferior P waves
  • ST depression or T-wave inversion inferiorly and in the V1
  • RV hypertrophy
  • Lastly, call for help. Both the underlying pathophysiology and the management of pulmonary hypertension and RV failure are incredibly complex. Most of these patients have a pulmonary specialist who manages their condition. Seek their advice as soon as possible.

Mohamed Hagahmed, MD
Assistant Clinical Professor
Department of Emergency Medicine
UT Health San Antonio
Email: [email protected]
Twitter: HagahmedMD

References

Wilcox SR, Kabrhel C, Channick RN. Pulmonary Hypertension and Right Ventricular Failure in Emergency Medicine. Annals of emergency medicine. 2015; 66(6):619-28. PMID: 26342901

Hoeper MM, Granton J. Intensive care unit management of patients with severe pulmonary hypertension and right heart failure. American journal of respiratory and critical care medicine. 2011; 184(10):1114-24. PMID: 21700906