The nurse cares for a client recently diagnosed with infectious mononucleosis. Which explanation best describes the microorganism that causes this disease?

Choice A reason: Decrease in sympathetic nervous system outflow is the best explanation because it is a condition that affects the regulation of blood pressure, heart rate, and skin temperature. The sympathetic nervous system is a part of the autonomic nervous system, which is the part of the nervous system that controls the involuntary functions of the body, such as breathing, digestion, and circulation. The sympathetic nervous system is responsible for the fight-or-flight response, which prepares the body for action or danger, by increasing the blood pressure, heart rate, and skin temperature. The sympathetic nervous system is composed of nerve fibers that originate from the thoracic and lumbar regions of the spinal cord, which are the middle and lower parts of the spinal cord. A complete spinal cord injury at the C3 to C4 level is a condition where the spinal cord is severed or damaged at the neck, which interrupts the communication between the brain and the rest of the body. A complete spinal cord injury at the C3 to C4 level can cause the loss of sympathetic nervous system outflow, which means that the nerve impulses that normally stimulate the blood vessels, the heart, and the sweat glands are reduced or absent. This can result in hypotension, which is a low blood pressure, bradycardia, which is a slow heart rate, and warm and dry skin, which are the observations noted in the client.

Choice B reason: Decreased fluid volume in the intravascular space is not the best explanation because it is a condition that affects the amount of fluid in the blood vessels, which can be caused by various factors, such as dehydration, bleeding, or vomiting. Decreased fluid volume in the intravascular space can cause hypotension, which is a low blood pressure, but it can also cause tachycardia, which is a fast heart rate, and cool and clammy skin, which are not the observations noted in the client.

Choice C reason: The effects of opiate medication administration is not the best explanation because it is a condition that affects the pain perception and the central nervous system, which can be caused by various types of medications, such as morphine, codeine, or oxycodone. The effects of opiate medication administration can cause hypotension, which is a low blood pressure, and bradycardia, which is a slow heart rate, but it can also cause respiratory depression, which is a slow and shallow breathing, and miosis, which is a constriction of the pupils, which are not the observations noted in the client.

Choice D reason: Onset of acute systemic bacterial infection is not the best explanation because it is a condition that affects the immune system and the whole body, which can be caused by various types of bacteria, such as staphylococcus, streptococcus, or salmonella. Onset of acute systemic bacterial infection can cause hypotension, which is a low blood pressure, but it can also cause fever, which is a high body temperature, and chills, which are sensations of coldness and shivering, which are not the observations noted in the client.

Choice A reason: The client has hypoglycemia during the night and hyperglycemia in the morning is the best explanation because it is the definition of the Somogyi effect, which is a rebound phenomenon that occurs in some people with type 1 diabetes mellitus. Type 1 diabetes mellitus is a condition where the pancreas does not produce enough insulin, which is a hormone that helps the cells use glucose, which is a sugar that provides energy for the body. The Somogyi effect happens when the blood glucose level drops too low during the night, usually due to taking too much insulin or not eating enough carbohydrates before bedtime. This triggers the release of hormones, such as glucagon, epinephrine, and cortisol, that raise the blood glucose level by stimulating the liver to produce more glucose and by preventing the cells from using glucose. This results in a high blood glucose level in the morning, which is called hyperglycemia.

Choice B reason: The client has not taken the prescribed insulin dose prior to the evening meal is not the best explanation because it is a factor that can cause the opposite of the Somogyi effect, which is the dawn phenomenon. The dawn phenomenon is a condition where the blood glucose level rises in the early morning, usually due to the natural increase of hormones, such as growth hormone and cortisol, that occur during the night. These hormones reduce the effectiveness of insulin and increase the blood glucose level. The dawn phenomenon can be worsened by not taking enough insulin or by eating too many carbohydrates in the evening.

Choice C reason: The client will have an abnormal glycosylated hemoglobin (HbA1c) for the next two months is not the best explanation because it is a consequence, not a cause, of the Somogyi effect. Glycosylated hemoglobin (HbA1c) is a test that measures the average blood glucose level over the past two to three months, by showing how much glucose is attached to the hemoglobin, which is the protein that carries oxygen in the red blood cells. The Somogyi effect can cause the HbA1c level to be higher than expected, because it reflects the high blood glucose level in the morning, not the low blood glucose level during the night.

Choice D reason: The client will experience complications earlier than other clients with type 1 diabetes mellitus do is not the best explanation because it is a general statement, not a specific explanation, of the Somogyi effect. The Somogyi effect can increase the risk of complications, such as eye, kidney, nerve, and heart problems, because it causes fluctuations in the blood glucose level, which can damage the blood vessels and the organs. However, the Somogyi effect is not the only factor that can affect the development and progression of complications. Other factors, such as genetics, lifestyle, and comorbidities, can also play a role.