**10. General principles in the treatment of shock**

In order to provide a patient with the benefit of rational and effective treatment, it is critical to identify the specific cause of shock in each case. Although treatment should be aimed at the underlying etiology of shock, the most critical aspect of treatment is the prompt restoration of normal hemodynamics.

From a hemodynamic perspective, there are three main categories in the management of shock:


In hypovolemic shock, the primary derangement is low central venous pressure (CVP) so therefore IV fluids are the cornerstone of therapy. If the patient is profoundly hypotensive, vasopressors are sometimes used temporarily but only while definitive access is obtained, and fluids are pushed as quickly as possible. If a patient in hypovolemic shock is requiring vasopressors to maintain enough perfusion pressure to stay conscious, they are in critical need for more fluid. Since these patients are already extremely hyper dynamic, there are no benefits of inotropes which will only risk worsening tachycardia to the point that diastolic filling time is too short for the left ventricle to fill.

In distributive shock, the primary derangement is low SVR. Vasopressors are therefore almost always necessary. Since most of these patients are also hypovolemic, or at the very least, have fluid maldistributed to the extravascular space rather than central circulation, IV fluids are also used in every case. Because of sepsis induced cardiomyopathy, some patients with sepsis may also benefit from inotropes but identifying those patients can be a challenge.

In cardiogenic shock, the primary problem is low cardiac output, thus inotropes are the mainstay therapy. Both fluids and vasopressors are not only unnecessary but contraindicated. In fact, reduction in preload by using diuretics, and reducing the afterload helps in augmenting the cardiac output in patients with cardiogenic shock.

Finally, in obstructive shock, it is impossible to generalize about the appropriateness of fluids, vasopressors and inotropes and if there is a response to any of those, it is likely only temporary. Definitive relief of the obstruction is still critical. For pneumothorax (PTX), this is either chest tube or needle thoracostomy which consists of a needle placed into the pleural space via the second intercostal space in the midclavicular line. For cardiac tamponade, pericardiocentesis can be performed, a procedure in which a needle is placed in the pericardial space most commonly via a subxiphoid approach. In case of massive pulmonary embolism, depending on the circumstances, this may require systemic thrombolysis or embolectomy.


General treatment principles are summarized in **Table 6**.

**Table 6.**

*General approach to therapy with regards to type of shock.*
