MSK; A&P and Drugs

Question 1

Presentation of Nitrous Oxide (Entonox)

Answer 1

1ml per 1ml medical gas in medical cylinders with a blue body and white shoulders

Question 2

Indications for Entonox

Answer 2

• Moderate to severe pain
• Labour pain

Question 3

Contra-Indications for Entonox

Answer 3

• Chest injury and/or clinically suspected pneumothorax
• Severe head injuries with impaired consciousness due to possible intracranial air
• Decompression sickness (can cause N2 bubbles in the blood to expand)
• Violently disturbed psychosis patients
• Abdo pain where intestinal obstruction is suspected
• Pt had an intraocular injection of gas in the last 8 weeks

Question 4

Actions of Entonox

Answer 4

Inhaled analgesic agent. Effects are quick but half life is also short

Question 5

Route and Dose of Entonox

Answer 5

• Self administrating via mouthpiece via inhaling
• Patient self administers when pain is present until pt gets unwanted side effects

Question 6

Presentation of IVP

Answer 6

1g in 100ml bottle

500mg in 50ml bottle (for paeds less than 33kg)

Question 7

Indications of IVP

Answer 7

Relief of mild to moderate pain or high temperature with discomfort

Question 8

Contra-Indications to IVP

Answer 8

• Known paracetamol allergy
• Pt already had paracetamol in the last 4 hours or if maximum cumulative dose has been reached

Question 9

Actions of IVP

Answer 9

An analgesic and antipyretic drug

Question 10

Dose for IVP

Answer 10

Adult:

INITIAL DOSE: 1g in 100ml

REPEAT DOSE: 1g in 100ml after 4-6 hours

MAX DOSE: 4g in a 24 hour period

Paed - use page for age

Question 11

Presentation of Morphine

Answer 11

10mg in 1ml ampoules

(Needs to be diluted with sodium chloride to create a 10mg in 10ml concentration)

Question 12

Indications of Morphine

Answer 12

• Pain assc w/ suspected MI
• Severe pain as part of pain ladder
• Oral morphine can be used as a component of managing moderate pain
• End of life indications

Question 13

Contra-Indications of Morphine

Answer 13

• Child under 1
• Respiratory depression
• Hypotension under 90
• Head injury with GCS less than 9
• Known hypersensitivity

Question 14

Actions of Morhpine

Answer 14

• Strong opioid analgesic
• Provides sedation, euphoria; may depress respiration and induce hypotensio
• Histamine release can contribute to vasodilation
• IV morphine takes a minimum of 2-3 mins to take effect with peak effect between 10-20 mins

Question 15

Route of Morphine

Answer 15

IM

IV/IO - slow admin of 2mg per minute

Question 16

Dose (IV) for Morphine

Answer 16

Adult (over 50kg):
INITAL DOSE: 10mg
REPEAT DOSE: 10mg after 5 mins
MAX DOSE: 20mg

Question 17

Function of Bones

Answer 17

• Framework for the body
• Allow movement
• Protection of organs
• Haemopoiesis - production of blood cells in red bone marrow
• Mineral storage - especially calcium

Question 18

Types of Bones

Answer 18

Long Bones - has a shaft and extremities eg femur, tibia, fibula

Short, irregular, flat and sesamoid bones - no shaft or extremities, diverse in shape and size

Question 19

Anatomy and Layers of Bone

Answer 19

Epiphysis - Wider section of bone at the ends
Diaphysis - long shaft of a bone
Blood supply (nutrients artery)
Periosteum - the outermost layer
Endosteum - the compact layer of bone just inside of the periosteum
Cancellous Bone - spongy part, has vascular suppy and metabolically active
Yellow bone marrow - innermost part of the bone amongst the cavity

Question 20

Classifications of Fractures

Answer 20

Closed- the bone ends don’t break the skin

Open - the bone breaks the skin (whether its gone back in or not)

Pathological - fracture caused by a disease/little trauma

Greenstick - fractures that occur in paeds where the bone isn’t fully developed

Question 21

Process of Bone Healing

Answer 21

1. A haematoma forms between the break
2. Inflammatory response brings macrophages that break down the haematoma and any bone fragments
3. Fibroblasts migrate to the site, granulation tissue and new capillaries develop
4. Osteoblasts secrete spongy bone and an outer layer of callus
5. The callus layer hardens over time becoming the new bone (often stronger than previous)

Question 22

Synovial Joints

Answer 22

• Bones are not in direct contact but divided by a ‘synovial space’
• Lined w/ synovial membrane which secrete synovial fluid, nourishing and lubricating articulating surfaces to reduce friction
• eg shoulder, knee, elbow

Question 23

Fibrous Joints

Answer 23

Bones are connected by dense fibrous connective tissue allowing only very small movement eg sutures of the skull

Question 24

Cartilaginous Joints

Answer 24

Bones connected by Cartlidge, usually provides little or no movement eg between vertebrae’s

Question 25

What are the 3 Groups of Muscle?

Answer 25

• Cardiac muscle
• Skeletal (voluntary)
• Smooth (involuntary)

Question 26

What Components Make up Muscle?

Answer 26

• Muscle tissue
• Connective tissue
• Nerve tissue
• Vascular tissue
• Myocytes - protein called actin and myosin that allow the body to contract and relax

Question 27

Contraction of Muscle

Answer 27

• The skeletal muscle cell contracts in response from a nerve fibre which supplies all the muscle
• The point which meets the muscle is called a neuromuscular junction
• The impulse will cause an influx of calcium triggering the binding of the muscles filaments (actin and myosin) to slide and shorten (contraction)
• If enough fibres are stimulated the entire muscle contracts

Question 28

Sprains vs Strains

Answer 28

Strain - overstretching/tearing of muscle or tendon
Sprain - ligaments are stretches or torn

Question 29

Ligaments

Answer 29

Ligaments connect bone to bone. Main function is to provide stability to articulating bones/reinforce joint

Question 30

Tendons

Answer 30

Tendons attach muscle to bone. They allow for movement as they are slightly elasticated but can be stretched too far causing a strain.