Exam 2023.2 Flashcards
(46 cards)
What’s ANZCA’s position on long acting opioid for acute pain?
Best avoided, unless there is a demonstrated need, close monitoring available, and a cessation plan in place
Define opioid stewardship
Coordinated interventions designed to improve, monitor, and evaluate the use of opioids.
What are the most important opioid related harm, ?
OIVI, persistent post discharge opioid use, opioid misuse and diversion
What are the three mechanisms of OIVI
Depression of central respiratory drive
Depression of consciousness
Depression supraglottic airway muscle tone
Downsides of long acting opioids?
increased risk of IVI
Higher risk of persistent post discharge opioid use
Inability to rapidly tritrate dosage
do not lead to better pain relief compared to short acting
Describe some patient selection criteria for day case hip surgery
Independently mobile
BMI < 35
Age <75
ASA 1 or 2
No signfiicant comorbidities or opioid use
General optimisation points for ERAS patients
Ensure proper nutrition and hydration
Optimise haemoglobin levels >100
Minimise fasting times
Key points on program design of ERAS pathway
Standardised anaesthesia protocols
Multidisciplinary team approach (surgeon, nurses, allied health)
Regular audit and feedback to ensure compliance and continuous improvement
Key points on ERAS pre-op stage
Patient assessment - selection criteria
Optimisation
Education - information about procedure, recovery process, set realistic exceptions on pain management
Define life-threatening haemorrhage
Blood loss of ~30-40% of total blood volume
Requires immediate resuscitation and surgical haemostasis to prevent hypovolaemia shock and end organ failure
Pelvic bleeding - why is it signfiicant?
Extensive vascular network, multiple sources of bleeding
Large potential space to accommodate large volume
Associated high-energy traumatic injuries - other sites?
Major haemorrhage -> consumptive coagulopathy
Options to control pelvic bleeding
Pelvic binder - approximate the fracture ends, reduce haemorrhage, stabilise pelvis
Surgical stabilisation - ex-fix , pelvic packing
Radiological embolisation
When could PiCCO be inaccurate?
Intracardiac shunt
Severe AS
Large PE
IABP
Severe arrhythmia
What’s the Stewart Hamilton Equation
Formula used to calculate cardiac output using indicator dilution method.
Generates graph of time vs. indicator concentration.
Area under curve then used to derive CO
In a PAC, what’s the size of the balloon?
1.5ml
In a PAC, what does the thermal filament do?
Allows continuous thermodilution
When PAC balloon is in RA, various waveforms are generated. What do these correlate to ?
a -
c -
x descend
v -
y descend
a - atrial contraction
c - triscupid valve elevation into RA
x - RV contraction, downward movement of RV
v - back pressure from blood filling the RA
y - triscupid valve opening
What are the 3 main West Zones
Zone 1 - dead space, alveolar pressure exceeds PA pressure, no blood flow
Zone 2 - Pa > PA > Pv , intermittent blood flow as alveolar pressure acts as a Starling resistor
Zone 3 - Pa > Pv > PA, continuous blood flow
What’s the effect of respiration on PCWP
Spontaneous breathing
- PCWP reduces on inspiration, increases on expiration
In IPPV
- PCWP increases on inspiration, reduces on expiration
How does thermodilutional method calculate the CO?
Cold bolus of saline / dextrose injected into RA
Users modified Stewart-Hamilton equation
Rate of blood flow (CO) is inversely related to the change in temperature over time.
Faster the blood flow, quicker the neutralisation of temperature
Use of naturetic peptide in preop evaluation
Valuable tool, cheap, readily available.
High negative predictive value, good predictor of death and non-fatal myocardial infarction at 30-180 days post surgery.
Optimal threshold for risk stratification not yet established.
What are the foundational therapies for heart failure
For NYHA II and above, use
- ACE inhibitor, ARBS
- Beta blockers
- Mineralcorticoid receptor antagonists
What are the advanced therapies for heart failure?
For patients with persistent symptoms despite foundation therapy
- Entresto (Neprilysin inhibitor-angiotensin receptor)
- SGLT-2 inhibitor
What are the non-pharmacological therapies for heart failure
Regular moderate-intensity exercise, sodium restriction, fluid restriction, daily weight, smoking cessation
Cardiac rehab.
