Notes

Pathophys

Tension Pneumo
Disruption involves the visceral pleura, parietal pleura, or the tracheobronchial tree. Injured tissue forms a one-way valve, allowing air inflow with inhalation into the pleural space and prohibiting air outflow. This will cause the lung to collapse on the ipsilateral side. As the pressure increases, it will cause the mediastinum to shift towards the contralateral side, contributing further to hypoxemia.

Open pneumo
As opposed to a tension pneumo, where injured tissue is a one-way valve and the pleural cavity pressure is greater than the atmosphereic pressure, an open pneumo has a two-way valve of air travelling in and out, resulting in pleural cavity pressure equalling atmospheric pressure.

Flail chest & Pulm contusion
*Free-floating segment of chest wall due to >2 rib fractures, each at two sites . Underlying lung contusion is cause of morbidity and mortality.

Massive hemothorax
*>1,500 cc blood loss in chest cavity.

Cardiac Tamponade
*Pericardial fluid accumulation impairing ventricular fuction.

Traumatic aort dissection
*90% tear at subclavian near ligamentum arteriosum. Most die



Complication
Tension pneumo

*In severe cases, the increased pressure can also compress the heart, the contralateral lung, and the vasculature leading to hemodynamic instability. This is due to impaired cardiac filling and reduced venous return. Hypoxemia also triggers pulmonary vasoconstriction and increases pulmonary vascular resistance. As a result, hypoxemia, acidosis, and decreased cardiac output can lead to cardiac arrest and, ultimately, death if the tension pneumothorax is not managed in a timely fashion.