Obstructive shock is a fall in blood flow caused by a physical obstruction in the heart or neighboring blood vessels. As the distribution of blood to the body declines, the patient’s tissues can begin to die because they don’t receive essential oxygen and nutrients. This can be rapidly fatal if the patient doesn’t receive treatment to resolve the obstruction, which might include inserting a needle to stabilize pressure inside the chest in the case of a tension pneumothorax. Some medical providers refer to this as cardiogenic shock because the origins of the problem often lie with the heart.
This can be a concern for patients with severe injuries to the chest, a history of clotting, or cardiovascular disease. One potential cause of obstructive shock is a pulmonary embolism, where a large blood clot blocks the pulmonary artery. Patients can also develop cardiac tamponade, where fluid fills the sac that surrounds the heart, or obstructive shock caused by a large tumor that puts pressure on the heart and blood vessels. Immediate treatment involves clearing the obstruction so the patient starts getting blood again, while long-term care requires addressing the underlying cause.
In patients with this condition, the ventricles of the heart may struggle to fill or empty, disrupting the heart beat. Without a regular beat, the heart cannot supply blood to the rest of the body and the blood pressure drops. Medical providers may note symptoms like abnormal chest sounds, extreme pallor, clamminess, and cold extremities. This condition can be fatal within minutes because the supply of blood is critical for the function of major organs like the brain, which can survive for only a limited amount of time without oxygen.
Some people are at higher risk of obstructive shock. This includes patients on bed rest or those with significant mobility impairments that make it hard to move around, along with patients who have clotting disorders, a history of arterial plaque, and cancer. In cases where people have injuries to the chest as a result of accidents, this may be considered as a risk factor and first responders should carefully check for breath sounds and a steady heart beat while performing an evaluation. Signs of obstructive shock are treated rapidly in the hopes of stabilizing the patient long enough to get to a hospital for advanced medical care.
It is also possible to develop obstructive shock unexpectedly, with no prior warning. Seemingly healthy patients may experience a fluke of circumstances that interferes with heart function or blocks one of the major vessels around the heart and lungs. This is sometimes the result of an undiagnosed prior condition that was initially asymptomatic until it was exacerbated by a factor like engaging in heavy physical activity.
