Anaes Flashcards
Causes of post-op hypoxia
tongue falling back
Benzos, opiates
Inhalationals
NMBAs
OSA
Shivering
Bronchospasm
Laryngospasm
Upper airway secretions
Causes of post-op hypotension
Inhalationals, opiods, induction agents
Epidural anaes
Bleeding
Sepsis
Pneumothorax
Cardiac tamponade
MI, HF
Causes of HTN
Pain
Distended bladder
Hypercapnia
Excessive IV fluids
Vasopressor use
Causes of PONV
?
Inhalationals
Full stomach
Young females and children
non-smokers
Obese
Hx of PONV
Laparoscopic surgery
Upper GI surg
Middle ear surgery
Causes of shivering post-op
Hypothermia
Use of volatile agents
Post-epidural anaes
Sepsis
Stages of anaesthesia
1 = Relative anaes
2 = Excitement/delirium
3 = surgical anaes
4 = medullary depression
what score for measure of physiologic recovery post-anaesthesia?
Aldrete score.
9 or above = safe discharge from PACU
When is RSI usu done?
Usu for pts with high risk of aspiration e.g. IO, GOO, GERD, esophageal patho, achalasia, acute abdo scenarios.
There will be pre-oxygenation, but no bagging using inhalationals.
ADR of opioids in intrathecal space?
Pruritus
Hypotension
N/V
What to watch out for in RA?
Resus drugs (for LAST)
IV access
Monitoring
Assistance
Drugs - which to use
Equipment
Factors that make spinal block difficult
Elderly, obesity
Complications of spinal block?
Hematoma
Bleeding
Infection
Cauda equina
Persistent block
Limitations of Pulse Oximeter?
- Less accurate at sats below 70
- Interference by ambient light
- Carboxyhemoglobinemia
- Loss of pulsatile component
- Movement artefact
Causes of inaccurate BP reading?
Cuff should be at level of heart
Patient moving/shivering
Wrong cuff size
When is NMJ monitoring used?
when NMBAs have been given.
Common one is “train of four”.
When is Bispectral index used?
Only when propofol is used for maintenance.
Risk factors for awareness intra-op?
Obese patient
Difficult intubation
Prior hx of intra-op awareness
Use of beta blockers
Use of low MAC agent
Cardiac, trauma, emergency and CSecs
Use of muscle relaxants
ASA status 4
Advantages of regional anaes?
Consciousness preserved
Minimal respi depression
Attenuate stress response
Good early post-op pain relief
Simple to administer
Disadvantages of regional anaes
Needs technical skill
Occasional inadequate blockade
Patient acceptance/cooperation
Complications of Regional anaes (wo LAST)
Failed blockade
Hypotension
Pneumothorax - brachial plexus block
Urinary retention - spinal block
Post-dural puncture headache
Motor blockade
Risk factors for post-dural puncture headache?
Young female
Pregnant
big needle
Pre-op hx taking unique to anaes?
Last meal, fluids
URTI
Smoking
Pregnancy
Family hx of anaes
OSA
Causes of HTN in op?
Light anaesthesia
Hypovolemia
Vasodilation
Hypercarbia
Hypoxia
Hyperthermia
Characteristics of bronchospasm?
Prolonged expiration phase
Wheeze
Increased peak airway pressures
Shark-fin appearance in ETCO2, common in post-morphine wheeze
Contraindications to Sux?
HyperK
Burns
Spinal cord injury
Malignant Hyperthermia
Contraindication to Etomidate?
Adrenal suppression
etomidate works fast
ADR of fentanyl?
chest wall rigidity
bradycardia
Cardiorespi depression is a given
Indications for Central Venous Line insertion?
Expecting hemodynamic instability
Access for TPN
Risk of air embolism
Conduit for pacing wires, pulmonary artery catheters, dialysis catheters
And ofc to give drugs
Pre-op in DM?
Postpone ops in poorly controlled DM.
Stop all OHA and insulin when NBM 6hr before.
Stop SGLT2 inhibitors 2 days pre-op.
Give dextrose drip if insulin given or CBG <5
Half dose basal insulin for T1DM / T2DM on insulin
Intra-op difficulty of DM?
Diabetic ANS dysfunction, cuz when intravascular vol changes, pt cant compensate with peripheral resistance as well.
Higher risk of CVS instability + delayed gastric emptying. High risk of pulmonary aspiration
Intubation might be difficult due to chronic hypergly causing glycosylation of tissue proteins. TMJ and cervical spine mobility can be limited
Intra-op mx of HTN?
Arterial BP kept within 20% of pre-op.
Do NOT allow hypotension.
Can use short-acting HTN e.g. esmolol during intubation.
Post-op mx of HTN?
Resume anti-HTN asap.
Effective pain mx
When to postpone elective surgery in Heart disease?
Recent ACS / decompensated CCF within 1/12
Bare-metal stent insertion within 1/12
Drug-eluting stent insertion within 6-12 months
First sign of MH?
Tachy
Raised ETCO2
Muscle rigidity
Why is pain mx impt in COPD pts?
severe pain can cause atelectasis and opioids can cause respi depression in pts with alr low respi reserves
Pre-op in COPD?
Pre-op chest physio
Optimize inhalers
Reduce secretions
Stop smoking min 8/52
