Click here to view next page of this article

 

Shock

Shock is a condition in which the cardiovascular system fails to support the bodyís basic metabolic needs. The basic systemic effects revolve primarily around vital signs. Shock causes in tachycardia. In the vast majority thatís true. However, as the heart sometimes fails, the response is bradycardia. That can result in hypotension and all of the other symptoms of shock. In patients, especially younger patients, who are dying from hypoxia or respiratory problems, frequently will present as a bradycardic rhythm in the late stages. When you see that in a child, it usually isnít a primary heart problem.

Hypotension is very frequently synonymous with the concept of shock. Hypotension or low blood pressure is basically the way that we look at a patient in shock. Itís because that is the best monitor we have of how well the patient is being perfused. Obviously, hypotension and perfusion are two different things. What weíd really like to know is how well organs are being perfused. But we really donít have good measurements of perfusion in the un-monitored patient and what we try to rely on is a patientís blood pressure to determine how severe the shock state is.

Another thing that frequently enters into it, vital sign-wise, is looking at the respiratory rate. Most patients who are hypotensive and tachycardic also become tachypneic. Thatís primarily a response to the metabolic acidosis that results from the shock state. In other words, poor perfusion resulting in changing of your respiratory type resulting in release of fixed acids which stimulates the respiratory tree to increase the respiratory rate. So when you see tachycardia, hypotension and tachypnea that is one of the more classic descriptions of the shock state. What we then do is add the vital signs to various other - what I refer to as - output.

The other thing that we tend to pay attention to when you are dealing with the hypotensive, tachypneic, tachycardic patient is the stimulation of compensatory responses. As a matter of fact, many of you of my age were taught to recognize shock based on these compensatory changes.

The other thing that we tend to think about also are some of the hormonal responses. Epinephrine, norepinephrine being the classic examples of some of the hormonal responses. Not only do they cause vasoconstriction but they also cause the tachycardia. When you clinically assess a patient in shock, I spend a lot of time actually looking at the periphery and looking at some of these compensatory changes. Hereís an example of myself examining a patient who is clinically in shock. This is a patient who actually at this time had a blood pressure in the 60ís who was dying.

So the general assessment should include the vital signs, the skin vitals, basic ABCís of how the patients is responding, what the level of consciousness of the individual is, and what their neurologic assessment it. These two can be somewhat different. By level of consciousness I mean their mental status. While you are thinking, also interceding in the disease process is important. I donít spend a whole lot of time worrying about why my patient is in shock. I spend a lot of time doing the basic stuff. Iím a surgeon and I tend to approach things in the primary process. And when Iím approaching a patient in shock what Iím doing is providing oxygen for the patient, making sure the patient is breathing adequately, does the patient need augmented respiration? Does the patient need to be intubated? What can I do to support the circulation? Should I cram in some IVís and start some fluid on the patient? Hopefully by that time I have woken up.

From the standpoint of the heart, cardiogenic shock is one of the major forms of shock types that you as clinicians deal with on a regular basis. Fortunately I donít deal with it as frequently as a surgeon, however I do see it from time to time. The other day I just finished fixing a guyís liver after he fractured his liver, and the patient got up to the intensive care unit and the patient was hypotensive, tachycardic and of course I had left the operating room and was heading home.

Pericardial centesis is the medical treatment of choice when somebody develops a pericardial tamponade, pressure around the heart. It is less commonly utilized in somebody who develops acute tamponade from a gunshot wound or a stab wound. But again, this process with decrease the amount of blood building up around the heart and hopefully decrease the pressure around the heart, and hence elevate the blood pressure, decrease the tachycardia and alleviate the problem. As I said, this was a temporizing process for the majority of things that I deal with, but occasionally it can be a definitive treatment for somebody with uremic effusions that are interfering with the mechanical activity of the heart.