What is the initial therapy of choice for the treatment of anaphylactic shock?

Choice A reason: Stroke volume x heart rate. Cardiac output is the volume of blood the heart pumps per minute, calculated by multiplying the stroke volume (the amount of blood ejected with each heartbeat) by the heart rate (the number of beats per minute).

Choice B reason: Afterload x preload. Afterload and preload are important factors influencing cardiac function but do not directly calculate cardiac output. Afterload refers to the resistance the heart must overcome to eject blood, and preload refers to the initial stretching of the heart muscle prior to contraction.

Choice C reason: Ejection fraction x blood pressure. Ejection fraction is a measure of the percentage of blood ejected from the heart with each beat, and blood pressure is the force exerted by circulating blood on the walls of blood vessels. These factors influence cardiac function but do not directly calculate cardiac output.

Choice D reason: Systolic x diastolic BP. Systolic and diastolic blood pressure are measurements of pressure during heartbeats and between beats, respectively. They are not used to calculate cardiac output.

Choice A reason:

Hyperactive bowel sounds are not typically associated with shock. Shock, particularly in its later stages, often leads to reduced perfusion to the gastrointestinal tract, which can cause decreased bowel activity. Hyperactive bowel sounds might be seen in other conditions such as gastrointestinal infections or bowel obstructions but are not characteristic of shock.

Choice B reason:

Diffuse tenderness upon palpation can be seen in various abdominal conditions, such as peritonitis or appendicitis, but it is not a hallmark sign of shock. While abdominal tenderness can occur if the patient has experienced trauma to the abdomen, it is not a primary sign used to diagnose shock.

Choice C reason:

Hypoactive bowel sounds are a common finding in patients experiencing shock. As the body prioritizes blood flow to vital organs like the brain and heart, blood flow to the gastrointestinal tract is reduced, leading to decreased bowel activity. This is consistent with the body's physiological response to shock and makes hypoactive bowel sounds the correct choice.

Choice D reason:

Cullen's sign, which is bruising around the umbilicus, is indicative of intra-abdominal bleeding, such as from pancreatitis or ruptured ectopic pregnancy. It is not a general sign of shock and would not be expected in all shock patients. Therefore, Cullen's sign is not the correct answer in this context.