Case 1 | Nursing homework help
Bad Fish: A Case Study on Nervous Tissue
Introduction
Tetrodotoxin (TTX) is a potent neurotoxin that is present in the tissues of puffer fish, a species commonly consumed in Asia. Ingesting puffer fish contaminated with TTX can lead to symptoms such as numbness, vomiting, paralysis, and even death. This case study focuses on Dr. Marshall Westwood, who experienced these symptoms after eating a meal of puffer fish and rice in Indonesia. This paper will analyze the signs and symptoms of TTX poisoning, the biology of nerve cells, and the effects of TTX on the nervous system.
Signs and Symptoms of TTX Poisoning
Diaphoresis refers to excessive sweating. In the case of Dr. Westwood, it is possible that the diaphoresis was a result of the body’s physiological response to the toxin, as the body tries to remove the toxin through the skin.
Motor dysfunction refers to the inability to control muscle movements, which can range from mild tremors to complete paralysis. In Dr. Westwood’s case, he experienced paralysis that started in his legs and spread to the upper body, arms, face, and head.
Paresthesias are a type of sensory disturbance that can cause sensations such as tingling, numbness, and prickling. Dr. Westwood reported feeling numbness in his lips and tongue, which quickly spread to his face and neck.
Cyanotic refers to a bluish coloration of the skin due to a lack of oxygen. Hypoventilation refers to a reduction in the rate and depth of breathing, which can lead to a decrease in the amount of oxygen in the body. In Dr. Westwood’s case, his cyanotic skin color and hypoventilation suggest that the toxin was affecting his respiratory system, making it difficult for him to breathe.
Bradycardia refers to a heart rate that is slower than normal, in this case 78 beats per minute. This slowing of the heart rate can be a result of the toxin affecting the electrical conduction system of the heart.
Gastric lavage is a procedure in which the stomach is washed out with fluid in order to remove any ingested toxins. In Dr. Westwood’s case, gastric lavage was used in an attempt to remove the TTX from his body.
Oxygen saturation refers to the amount of oxygen in the blood, expressed as a percentage of the maximum amount that can be carried. A normal oxygen saturation is between 95-100%, with Dr. Westwood’s oxygen saturation at 97% on room air.
Biology of Nerve Cells
Voltage-gated sodium ion channels are proteins that are located in the membrane of nerve cells. These channels are responsible for allowing sodium ions to enter the cell, which creates a change in the electrical potential of the cell. This change in electrical potential is called an action potential.
The resting membrane potential (resting potential) of a nerve cell is generated due to the unequal distribution of positive and negative charges on either side of the nerve cell membrane. The inside of the cell is negatively charged, while the outside is positively charged. This charge difference creates an electrical potential across the membrane.
When a nerve cell receives a stimulus, such as a touch or chemical signal, the voltage-gated sodium ion channels open, allowing sodium ions to enter the cell. This influx of positive charge further depolarizes the cell, making it more positive. If the depolarization reaches a certain threshold, an action potential is generated.