Week 2 - Muscular System Flashcards
What are some relevant nursing actions?
- Standard and aseptic hand washing
- Intramuscular injection
- Active and passive limb exercises.
- Nursing immobile patient, risk / falls assessment, pressure injury development.
- Assessment and recording: Blood glucose levels, heart rate, respiratory rate, temperature, BP.
List the function(s) of skeletal muscle.
- Pull on bones for movement, bone density
- Body posture, stabilise joints
- Generate heat
- Glycemic control
- Venous and lymph flow
- Protects organs
- Some sphincters (voluntary)
Name the two regulatory proteins that block the myosin heads from binding to the actin filaments within the sarcomere (Figure 7.4).
- Troponin
- Tropomyosin
Cardiac muscle also utilises actin, myosin, troponin and tropomyosin for muscle contraction. Linda’s father suffers from an apparent heart attack and is rushed off to the emergency room of the local hospital. The doctor tells her that he has ordered some blood work and he will be able to determine whether her father has had a heart attack.
1. Why would knowing the blood level of cardiac troponin help to determine this?
- Cardiac troponin is only found in the heart
- It is evidence of myocardial damage
Define neuromuscular junction.
Site of communication between neuron and a muscle cell (synapse)
Describe the function of a neurotransmitter.
- Released from axon terminal of neuron
- Diffuses across synaptic cleft
- Binds to receptor
- Stimulates adjacent cell (neuron or muscle)
When acetylcholine (ACh) binds to its receptor on the sarcolemma an electrolyte rushes into the sarcoplasm of the muscle cell which initiates the formation of a new action potential. Name this dominant electrolyte.
Sodium (Na+)
The enzyme acetylcholinesterase breaks down the ACh in the receptor to terminate the stimulation of the muscle so that it can relax. However, many insecticides contain toxins that interfere with the action of this enzyme.
George is using an insecticide and is very careless. Because he is not wearing gloves or a mask, he absorbs some of the chemical through his skin and inhales a large amount as well. List some signs would you expect to observe in George because of this poisoning
- ACH not removed
- Muscle continues to be stimulated, which causes persistent contractions (spastic paralysis)
Name two anatomical features of skeletal muscle that make it an effective delivery site.
- Big, large dose
- Vascular - Fast absorption and less sensitive to irritating and viscous medications
State why the nurse pulls back the syringe plunger (aspirates) before injecting the medication.
Ensure needle not in vein (intravenous injection)
Explain the reason for the nurse to wear gloves when administering an intramuscular injection.
Contamination with body fluid such as blood
Discuss the rationale for active and passive limb exercises in a patient.
- Maintain muscle mass
- Leverage on bones, maintains bone density
- Facilitate venous and lymph flow
- Warm patient up
Muscle cell cytoplasm
Sarcoplasm
Muscle cell
Muscle fiber
Bundle of muscle cells
Fascicle
Plasma membrane of muscle cell
Sarcolemma
Cord of connective tissue (collagen fibers) attaching bone to bone
Ligament
Cord of connective tissue (collagen fibers) attaching muscle to a bone
Tendon
Patients who are restricted in their movement due to illness and or treatment will experience a loss of skeletal muscle mass. This condition is described as ______.
Sarcopenia
Contractile unit of a muscle cell
Sarcomere
To maintain a healthy population of mitochondria as part of a healthy lifestyle, it is recommended to walk (move) at least ______ minutes per week. The level of benefit will vary based on the intensity of the exercise. However, any skeletal muscular contraction (movement) is better for your health outcomes than none, so avoid sitting at your desk for long periods.
150
Regulatory protein(s) involved in the interaction of actin and myosin
Troponin and tropomysin
Long striated organelle within sarcoplasm of muscle cell
Myofibril
This loss of skeletal muscle mass will reduce a patients’ capacity to ______.
- Control their blood glucose level
- Maintain a body temperature of 36.5 to 37.5
- Promote venous blood and lymph flow
Mitochondrial dysfunction is linked to conditions such as diabetes mellitus, obesity, cancer and mental illness. A healthy population of mitochondria ensures that an abundant supply of ATP is maintained via ______.
Aerobic respiration
List five features of smooth muscle.
- Smooth in appearance due to absence of sarcomeres
- Capable of mitosis (hyperplasia)
- Contracts in response to stretch
- Fatigue resistant
- Myosin pulls on actin; actin pulls on dense bodies
List five bodily functions that require the contraction of smooth muscle.
- Vasoconstriction
- Peristalsis, churning and segmentation
- Closing on involuntary sphincters
- Expulsion of urine from bladder
- Uterine labour associated with birth
