The nurse provides care for a client diagnosed with complete spinal cord injury at the third and fourth cervical (C3 to C4) level that occurred six hours ago. The client's BP is 82/42 mm Hg, apical heart rate is 96 beats/min, and the skin is warm and dry. Which explanation is best for these observations?

Choice A reason: Inflammation of white matter in the brain and spinal cord is not the best explanation because it is a condition that affects the transmission of nerve impulses, not the perception of sensory stimuli. White matter is the part of the nervous system that consists of myelinated axons, which are the extensions of nerve cells that carry electrical signals from one cell to another. Inflammation of white matter can be caused by various factors, such as infections, autoimmune diseases, or trauma, and can result in symptoms such as weakness, numbness, or paralysis.

Choice B reason: Increased levels of gamma-aminobutyric acid (GABA) in the brain stem is not the best explanation because it is a condition that affects the regulation of muscle tone, not the perception of sensory stimuli. GABA is a neurotransmitter, which is a chemical messenger that transmits signals between nerve cells. GABA is an inhibitory neurotransmitter, which means that it reduces the activity of the nerve cells that it binds to. GABA is mainly found in the brain stem, which is the part of the brain that connects the spinal cord to the cerebrum and cerebellum, and controls vital functions such as breathing, heart rate, and blood pressure. Increased levels of GABA in the brain stem can cause symptoms such as spasticity, rigidity, or tremors.

Choice C reason: Decreased levels of endorphins in the pons and medulla is not the best explanation because it is a condition that affects the modulation of pain, not the perception of sensory stimuli. Endorphins are neurotransmitters that act as natural painkillers, by binding to the opioid receptors in the brain and spinal cord, and blocking the transmission of pain signals. Endorphins are produced by the pituitary gland and the hypothalamus, which are parts of the brain that regulate the hormonal and nervous systems. The pons and the medulla are parts of the brain stem that are involved in the control of voluntary and involuntary movements, such as chewing, swallowing, coughing, sneezing, and blinking. Decreased levels of endorphins in the pons and the medulla can cause symptoms such as increased sensitivity to pain, anxiety, or depression.

Choice D reason: Hypoxia and necrosis of the parietal lobe neurons is the best explanation because it is a condition that affects the processing of sensory stimuli, such as touch, pain, temperature, and position. The parietal lobe is the part of the cerebrum that is responsible for integrating and interpreting sensory information from different parts of the body. The parietal lobe is divided into two hemispheres, each corresponding to the opposite side of the body. A left-sided intracerebral hemorrhage is a condition where a blood vessel in the left parietal lobe ruptures, causing bleeding and swelling in the brain tissue. This can damage the neurons, which are the nerve cells that communicate with each other and form the basis of the nervous system. Hypoxia and necrosis of the parietal lobe neurons can cause symptoms such as loss of sensation, neglect, or agnosia on the right side of the body.

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.