Injections and anasthesia

Question 1

Where does the spinal cord terminate in the adult?

Answer 1

L1/L2 vertebrae

Question 2

Where does the spinal cord terminate in children?

Answer 2

L2/L3 vertebrae

Question 3

Where does the subarachnoid space (filled with CSF) terminate?

Answer 3

S2 vertebrae

Question 4

What does the supracristal plane mark?

Answer 4

The higest point of the iliac crest

L4 spinous process

Question 5

Describe how a lumbar spinal puncture is performed

Answer 5

Lumbar punctures are performed to obtain a sample of CSF.

The patient is positioned leaning forward or lying onthe side with back flexed. This spreads teh laminae and spinous processes apart.

The needs is inserted into the subarachnoid space at the midline between the spinous process of L3/L4 vertebrae in an anterosuperior direction (15 degree angle)

Question 6

What region of the spine is anaesthesia administered to the CSF?

Answer 6

Between L3/L4 to L5/S1

Needle is passed into the subarachnoid space where teh anesthetic is administered

Question 7

Where would you administer caudal anasethesia?

Answer 7

Sacral hiatus

Blocks S2-S5

Question 8

What is the effect of epidural anaesthesia?

Answer 8

An anesthetic agent can be injected into the epidural space by inserting a sterile needly into the spine between the spinous processes of L3/L4.

The anesthetic has a direct effect on the spinal nerve roots of the cauda equina after they exit from the dural sac. The patient loses sensation inferior to the level of the block.

The angle at which the needle is inserted depends on the region of the spine injected. e.g. in thoracic region angle of needle increases towards the head.

Question 9

Describe the two methods used to deliver IM injections in the gluteal region

Answer 9

1. Vertical line from the highest point of the iliac crest. Horizontal line midway between the ighest point of the iliac crest and the ischial tuberosity. Inject in the upper lateral quadrant
2. Vertical line from the highest point of the iliac crest. Horizontal line from the PSIS to the greater trochanter. Inject in the upper lateral quadrant

Question 10

Phlebotomy

Answer 10

Sampling of blood from superficial veins

Normally perfoemd at cubital fossa of upper limb. Can access cephalic (safest), basilic or median cubital vein

Question 11

Use of a cannula in taking blood

Answer 11

Put in place where repeat blood samples are required

Used for short term venous access

IV fluid infusion (fluid, blood drugs)

Repeated drug administration

Measuring central venous pressure

Question 12

Borders of the cunital fossa

Answer 12

Epicondylar line,

pronator teres

brachoradialis

Question 13

Stae 4 complicatins of superficial venous cannulation

Answer 13

Venous inflammation

Thrombosis

Thrombophlebitis (clot and inflammation)

Sepsis

Tissue infusion

Question 14

What are the common locations for superficial vein cannulation?

Answer 14

Cubital fossa

Dorsum of the hand

Anatomical snuffbox

Medial ankle (with a cutdown)

Question 15

What are theborders of tha anatomical snuffbox?

Answer 15

Superior: Extensor pollicis longus

Inferior: Extensor pollicis brevis and
Abductor pollicis longus

Question 16

Describe the course of the great saphenous and small saphenous vein

Answer 16

Great saphenous vein: Passes from the dosrum of the foot anterior to the medial malleolus up the medial aspect of the lower limb. Runs along the medial tibial border with the saphenous cutaneous nerve, posterior to the patella and up the medial thigh to the saphenous opening at the pubic tubercle where it drains into the femoral vein.

Small saphenous vein: Passes from the lateral part of the foot, posterior to the lateral malleolus into the posterior leg. It ascends in the midline along the sural cutaneous nerve then enters teh popliteal fossa to drain into the popliteal vein.

Question 17

Where would you cannulate a child?

Answer 17

Cubital fossa

Dorsum of the hand

External jugular vain

Scalp

Interosseous of anterior tibia

Venous cutdown (saphenous vein)

Question 18

Describe the ligation method of cannulating the saphenous vein

Answer 18

Blunt dissection of saphenous vein from saphenous nerve for 2cm.

Ligate teh distal mobilised vein

Pass a tie around the proximal part of the vein

Make a small incision in the vein

Introduce a cannula and tie with the proximal suture

Attach IV line to cannula

Question 19

When would arterial cannulation be required?

Answer 19

To asess acid-base status

Measuremen of arterial blood gases

Assessment of respiratory/cardiac/renal failure

Drug overdose

DKA

Lactic acidosis

Cardiac catheterisation

Question 20

State 4 complications of arterial cannulation

Answer 20

Haematoma

Arterial spasm leading to ischemia

Retrograde embolism

Traumatic aneurysn

Infection/sepsis

Question 21

Name three arteries commonly accessed for cannulation

Answer 21

Brachail artery

Radial artery

Femoral artery

Question 22

What are the borders of the femoral triangle?

Answer 22

Inguinal ligament

Sartorius

Adductor longus

Question 23

Describe the standard method for cannulating the saphenous vein

Answer 23

Blunt dissection of the saphenous nerve from the saphenous vein

Puncture the vein with an IV catheter

Introduce the cannula and withdraw the needle

Confirm free flow of blood

Attach IV line to cannula

Question 24

How do you access the saphenous vein for cannulation?

Answer 24

Identify the medial malleolus

Palpate the great saphenous vein (2cm anterior)

Measure 1cm anterior and superior to medial malleolus

Make an inscision 2.5cm from the anterior point to the posterior border of the tibia