Local anaesthetic for suturing
Given via s.c. injection, using a fine bore needle.
Lidocaine / Bupivacaine
+/- adrenaline to cause vasoconstriction, to reduce bleeding.
Draw back before injecting to confirm you aren’t in a blood vessel
Where should adrenaline never be used in combination with the local anaesthetic?
NEVER use adrenaline near end arteries (i.e. on fingers, toes, ears, nose, penis) as this can cause ischaemia.
Lidocaine for suturing LA
Onset = 5 mins
Duration = 1.5 hours
Dose = 3 mg/Kg
Dose with adrenaline = 7 mg/Kg
Max dose of Lidocaine is always 200mg, regardless of the patient’s weight.
Bupivacaine for suturing LA
Onset = 30 mins
Duration = 18 hours
Dose = 2 mg/Kg
Dose with adrenaline = 3 mg/Kg
Signs of Local Anaesthetic Toxicity
EARLY:
* Tinnitus
* Difficulty with visual focus
* Dizziness or lightheadedness
* Anxiety, agitation, confusion, disorientation, drowsiness
* Perioral and/or tongue numbness
* Metallic taste
LATE:
* CNS – seizures, coma
* CVS – bradycardia, hypotension, atrial and ventricular dysrhythmias, conduction blocks, cardiovascular collapse, asystole
* Respiratory – respiratory depression, apnoea.
* Methaemoglobinaemia – blue mucous membranes progressing to CNS and cardiovascular manifestations of cellular hypoxia and then death.
Causes of local anaesthetic toxicity
Size of suture
0 = Very large; For the abdominal wall
3.0 = For skin
5.0 = For the face
6.0 = For vascular anastomoses
8.0 = For ophthalmology
10.0 = As small as a hair; For microvascular anastomoses
Suture removal timing
Face – 5 days
Scalp – 5-7 days
Upper limb/groin – 7 days
Chest – 7-10 days
Abdo – 10 days
Lower limb/back – 10-14 days
Types of Suture
Absorbable = broken down by the body over time by processes such as hydrolysis and enzymatic degradation; usually used under the skin or in a non-compliant patient.
Non-absorbable = remain in place until removed; usually best for the skin.
Braided = easier to tie, but increased risk of infection.
Non-braided = break more easily, but less bacterial colonisation.
What sutures are typically used for skin?
Non-absorbable, non-braided
=> Ethilon, Prolene
Suturing - BEFORE
Suturing - DURING
Suturing - AFTER
Surgical Knot
Prepare to do next suture at a suitable distance.
Osler’s Nodes
= Tender red nodules in the fingers due to immune complex deposition
Roth’s Spots
= Pale areas with surrounding haemorrhage on the retina.
Janeway Lesions
= Painless palmar / plantar macules
Respiratory Examination - lobectomy
Inspection
- Thoracotomy scar (or can be laparoscopic).
- Chest wall flattening on the side of surgery
Palpation
- Tracheal displacement towards the surgical site
- Reduced expansion on that side.
Percussion
- Hyper-resonant on the side of lobectomy, as the remaining lung expands to fill the cavity.
Auscultation
- Reduced air entry over the site.
Causes of clubbing
C
Cyanotic/Congenital Heart Disease
CF
L
Lung cancer / lung abscess
U
Ulcerative Colitis
B
Bronchiectasis
B
Benign Mesothelioma
I
Infective Endocarditis & Idiopathic Pulmonary Fibrosis
N
Neurogenic Tumours
G
GI disease (e.g. liver disease, Coeliac)
ECG lead position - Limb leads
aVR (R)
Right arm (wrist)
aVL (Y)
Left arm (wrist)
aVF (G)
Left Leg
Neutral (B)
Right leg
ECG lead position - chest leads
V1 4th ICS, right sternal edge.
V2 4th ICS, left sternal edge.
V3 midway between V2 and V4
V4 5th ICS, midclavicular line
V5 5th ICS, anterior axillary line
V6 5th ICS, mid-axillary line
What is the normal calibration for the ECG trace?
Amplitude (height)
=> 10mm/mV
=> 1 small square = 0.1mV
=> 1 large square = 0.5 mV
Duration (speed)
=> 25mm/s
=> 1 small square = 0.04 sec
=> 1 large square – 0.2 sec
Approach to interpreting an ECG