Chronic Post Surgical Pain Prediction

A summary of risk factors :- genetic, age (young), female, pain sensitivity (like fibromyalgia), psychosocial (e.g. anxiety, depression, late return to work), pre-op pain, acute post-op pain, surgery/nerve injury.

The hypothesis is if we can identify and manage and treat promptly, we may prevent transition to chronic pain. A frequent problem is determining if these are just markers for chronic pain development or risk factors causally related to future pain. Nonetheless multimodal analgesia is the least we can do.

Pain

Hypotension, MI and Death

Intra or post op hypotension increases myocardial infarction and death. Various definitions – often cited as 40% drop in MAP or MAP below 55, and duration figures as a factor. I prefer minimum MAP 65-70 and systolic 90-100.

A big array of studies trying to define the magic figure. The important message is to treat it promptly.

Here defined as systolic < 90  Anesthesiology article

 

Prehabilitation

Yes it’s a word. Although the evidence is still just coming in, enhanced recovery after surgery may begin preoperatively for major surgery. It’s a “combination of aerobic training, resistance training and inspiratory muscle training to promote positive adaptations in cardiorespiratory fitness, muscular strength and endurance and respiratory muscle function, respectively”.

Anaesthesia guidelines

Cricothyrotomy (FONA)

The wire guided Seldinger technique (that was easy enough for an anesthesiologist to understand!) is no longer recommended. If the membrane is palpable, one full thickness transverse incision into the trachea; if not palpable an initial vertical incision so you don’t end up above the larynx.

A FONA (front of neck airway) Difficult Airway Society video that we all hope never to re-enact!

Front of Neck Airway

 

Top medical news this week

 

BRCA mutation doesn’t affect young onset breast cancer survival link

Consider evidence before prescribing gabapentinoids outside approved indications link

Genetic obesity predisposition has as much or more to gain from healthy diet link

Curb opioids like Codeine in cough medications. Only for over 18 year old link

Infants must sleep on back, not in your bed, no soft bedding or objects. Not everyone knows this still link

Peripheral Nerve Injury in Anesthesia

Attention to detail in positioning and knowing the risk factors like diabetes, thyroid disease, alcohol, “Established peripheral neuropathy, pre-existing (but subclinical) peripheral neuropathy, profound hypothermia, hypovolaemia, hypotension, hypoxaemia, electrolyte disorders, malnutrition, small or large body mass index (BMI), tobacco use and anatomical variants (such as the presence of cervical ribs) may increase the susceptibility of peripheral nerves to peri-operative injury”.

The complexity of predisposing conditions, surgical injury and tourniquet use are explored in the ASRA practice advisory  ASRA advisory

Anesthesiology (Here) publishes guidelines Jan 2018 for the prevention of peripheral nerve injury. Avoid pressure on nerves with padding if needed, avoid excessive flexion or extension of any joint, and none of those pesky  shoulder brace thingies. And I’ve saved you a lot of reading!

Anaesthesia article (free)