Day 9: Emergency and Trauma Anaesthesia Flashcards
what is emergency
-Imminent threat to life or limb exists
-Surgery must be done in 1-2 hour
what is urgent
-Requires surgery within 24 hours
-Allows time for optimisation
triage: red
immediate surgery
triage: orange
surgery within 2 hours
triage: yellow
surgery within 6 hours
triage: green
surgery within 24 hours
triage: blue
elective/ surgery within 72 hours or next elective list
triage: purple
time lapsed; needs to be reclassified
contributors of risk: situational factors
-Limited time to assess and prepare patient
-Junior staff
-After hours
-Uncertain diagnoses
-Situational awareness of staff may vary
contributors of risk: clinical factors
-Full stomach
-Intravascular depletion
-Electrolyte derangements
-Anaemia and coagulation abnormalities
-Co-morbidity
-Pain
anticipating complications in CVS
-Ongoing haemorrhage
-Hypovolaemia
-Hypotension
-Coagulopathies
-Dysrhythmias
anticipating complications: trauma
C spine injuries
Airway injury
anticipating complications: metabolic
Electrolyte abnormalities
Renal dysfunction
other anticipating complications
-adverse drug reactions
-hypothermia
What is Mendelson’s Syndrome?
Mendelson’s Syndrome refers to chemical pneumonitis caused by aspiration of gastric contents during anesthesia.
What causes chemical pneumonitis in Mendelson’s Syndrome?
Chemical pneumonitis in Mendelson’s Syndrome is caused by the aspiration of vomited or regurgitated gastric contents, leading to inflammation of the lungs.
When does aspiration of gastric contents commonly occur during anesthesia?
Aspiration of gastric contents commonly occurs during anesthesia when there is a loss of laryngeal reflexes, such as during general anesthesia, sedation, or a decrease in the level of consciousness.
Under what conditions does the risk of aspiration increase during anesthesia?
The risk of aspiration increases during anesthesia when there is sedation or a decrease in the level of consciousness, as these conditions can lead to relaxation of the laryngeal muscles and loss of protective airway reflexes.
when does aspiration usually occur
Usually occur 2 – 5 hours after anaesthesia
clinical features of aspiration
-Cyanosis
-Dyspnoea
-Wheezes and crackles
-Hypoxia
-Tachyardia with a high BP
-CXR signs are delayed even further – RML and RLL involvement
what is vomiting
Vomiting is an active process
Occurs at lighter planes of anaesthesia
Induction and emergence
Vomitus stimulates spasm of the cords + apnoea
what is regurgitation
Regurgitation is a passive process
Occurs at any time
Often “silent”
Usually at deeper planes of anaesthesia
Laryngeal reflexes are reduced or paralysed
aspiration risk
-full stomach
-pregnacny
-emergency and trauma
-airway trauma
-decreased GCS
-pain and opiates
-abdominal masses
*obesity >30
*ascites
*tumors
when to assume a full stomach
*Absent or abnormal peristalsis (Ileus
*Obstructed peristalsis
*Delayed gastric emptying
Absent or abnormal peristalsis (Ileus)
-Post-op
-Metabolic (DKA, uraemia, ↓K+)
-Drug-induced (opioids, anticholinergics
Obstructed peristalsis
Bowel obstruction
Gastric carcinoma
Pyloric stenosis
Delayed gastric emptying
Shock of any cause
Diabetes
Trauma
Pregnancy and labour
Fear, pain, anxiety
how to prevent aspiration
-empty the stomach
-neutralise the stomach acid
-avoid GA if possible
-rapid sequence induction with cricoid pressure
empty the stomach
Delay
NGT & suction
Prokinetics – e.g. Metoclopramide
neutralise the stomach
Antacids e.g. Sodium Citrate
H2-blockers – e.g. Ranitidine
PPI’s – e.g. Omeprazole
immediate management of aspiration
-80-100 % O2
-Minimise risk of further aspiration…
Left lateral position (L side down)
Head down (always use a tilting table in theatre)
Oropharyngeal suction before ventilation
-ETT if ventilation or suctioning required
further management of aspiration
-Treat as foreign body
Minimise positive pressure ventilation
Consider bronchoscopy
-NGT to help empty stomach
-Monitor respiratory function
-CXR looking for collapse or consolidation
-Consider ICU admission
Do well with 12 – 24 hours IPPV
-No routine antibiotics or steroids
when NOT to do an RSI
High risk of airway loss
-Facial and airway trauma
-Patients in imminent danger of losing their airway
-Patients unable to open their mouth
-Jaw / tongue / large neck abscesses
-Fixed neck deformities
-Base of Tongue / pharynx tumours
what to do if you can’t do RSI
-Awake fibre-optic intubation
-Front of neck access / awake tracheostomy by ENT
-Senior, skilled anaesthetist refer if necessary
when do you abandon airway intubation for ventilation
the moment the patient starts desaturating below 90%
preparation for the RSI
-Routine machine and equipment check
-Skilled assistant for cricoid pressure
-Tilting bed / table / trolley
-Patient supine in sniffing position
-Suction at arms length and switched on
-Patient monitoring attached with baseline readings
-Plan for failed intubation
-Wake up patient?
RSI induction: pre oxygenation
-80 % (100 %) O2 for 3 min
-Tight fitting mask on anaesthetic breathing circuit.
-O2 flow rate > 4 L/min
-Get a good trace on the capnograph
RSI induction: before injection
-Ensure IV line is working!
-Opioid often given before induction
Fentanyl 1-2µg/kg
Alfentanil (Rapifen) useful for dampening intubation response
-Final check that all equipment is ready
-Assistant happy?
RSI induction: induction agent
-Predetermined dose must be given up front
-Any IV induction agent is suitable depending on clinical scenario
-Etomidate or ketamine for hypotensive / shocked patients (will not tolerate large dose of propofol)
RSI induction: relaxant
Standard relaxant Suxamethonium 1–2 mg/kg
Suxamethonium contraindicated? Rocuronium 0.9-1 mg/kg
RSI technique of intubation
- The assistant must apply cricoid pressure before LOC
2.NOW WE WAIT. This is the key difference between an RSI and a standard sequence induction — we do not bag.
3.ETT insertion after fasciculations (45-60 sec after sux)
4.Inflate ETT cuff
5.IPPV and tests to confirm ETT position (CO2)
6.Assistant releases cricoid pressure only after confirmation of ETT in correct position
What is Sellick’s maneuver, also known as cricoid pressure?
Sellick’s maneuver, or cricoid pressure, is a technique used in anesthesia where pressure is applied to the cricoid cartilage to compress the esophagus against the vertebral column, preventing regurgitation of gastric contents.
How does cricoid pressure aim to prevent regurgitation during anesthesia?
Cricoid pressure aims to prevent regurgitation during anesthesia by physically obstructing the esophagus, thereby reducing the risk of gastric contents entering the airway.
When should cricoid pressure be applied during the anesthesia induction process?
Cricoid pressure must be applied before the patient loses consciousness, typically before anesthesia induction begins. It is important to identify the cricoid cartilage before induction and warn the patient about potential discomfort. If the patient vomits actively, cricoid pressure should be relieved to prevent esophageal injury.
confirmation of ETT placement: definitive signs
1.Visualising ETT go through cords
2.Conitnuous capnography trace
3.Oesophageal detector device (rarely used)
confirmation signs of ETT placement
1.Misting of the ETT
2.Bilateral chest rise
3.Auscultation
in emergency which induction should you use
Use cardiac stable drugs
Etomidate, Ketamine
Careful with Propofol
during emergency which volatiles should you use
-Iso, Sevo, Des
-Opiate-based anaesthetic for the critically ill
who needs ICU
-prolonged shock of any cause
-massive sepsis
-ischemic heart disease
-extreme obesity
=overt gastric acid aspiration
-pulmonary disease
-requiring inotropes
-hypothermia (temp<34)
-intra abdominal packs
-respiratory failure
-renal failures
