CRITICAL INCIDENCE Flashcards
(100 cards)
1
Q
List patient factors that predispose a patient to harm from intra-arterial injection.
A
- Unconsciousness and unable to report pain
- Hypotension/hypoxia and unable to recognize cannula as arterial
- Anatomical variation – artery cannulated in abnormal location
2
Q
List two organizational factors that may predispose to intra-arterial injection.
A
- Poor training resulting in failure to differentiate between artery and vein prior to cannulation
- Failure to label line as arterial/attach to appropriate equipment
3
Q
Name two drug features that increase the likelihood of severe injury from intra-arterial injection.
A
- Vasoactive drugs (e.g., noradrenaline)
- Cytotoxic drugs (e.g., chemotherapy)
- Hyperosmolar drugs (e.g., mannitol, TPN)
- Alkaline drugs (e.g., thiopentone)
4
Q
Describe three mechanisms of injury following intra-arterial injection.
A
- Arterial spasm leading to distal ischaemia
- Chemical arteritis causing direct tissue damage
- Drug precipitation and crystal formation causing thrombosis and ischaemia
- release of chemical mediators e.g. thromboxane – thrombosis etc
5
Q
List three acute clinical features of intra-arterial injection.
A
- Failure of drug to have intended effect
- Pain at and distal to injection site
- Pallor, cyanosis, and coolness of the limb or red and warm
- Paraesthesia
- Loss of distal pulse
6
Q
Outline seven steps in the management of intra-arterial injection.
A
- Stop injection
- ABC assessment - – may need to still urgently give drug by intravenous route
- Keep cannula in for intra-arterial treatment
- IA iloprost
- IA local anaesthetic
- Elevation
- Anticoagulation
- Pain control (e.g., stellate ganglion block)
- Involve vascular surgeons/radiologists/plastics
- Duty of candor – inform patient and family
- Incidence reporting
7
Q
What is extravasation?
A
The accidental leakage of IV fluid or medication from a vein into surrounding tissue.
8
Q
List causes of extravasation.
A
- Cannula dislodgement or vein rupture
- Fragile veins (e.g., neonates, elderly)
- High-pressure infusions
- Irritant drugs (e.g., chemotherapy)
9
Q
What are the effects of extravasation?
A
- Local pain
- Swelling
- Redness
- Blistering
- Necrosis
- Compartment syndrome
10
Q
What are the management steps for extravasation?
A
- Stop infusion
- Aspirate from cannula
- Assessment of high-risk factors
- Elevate limb
- Apply appropriate compress (cold/hot)
- Consider antidotes (e.g., hyaluronidase)
- Plastics referral if severe
11
Q
List high-risk patient factors for harm post-extravasation.
A
- Extremes of age
- Peripheral vascular disease
- Neuropathy (e.g., diabetes)
- Immunosuppression
12
Q
Name anaesthetic drugs that are bad to extravasate.
A
- Noradrenaline
- Thiopentone
- Gentamicin
- High concentration potassium
13
Q
What is the incidence of accidental awareness during general anaesthesia (AAGA) according to NAP 5?
A
- 1 in 19000
14
Q
What is the incidence of AAGA if neuromuscular blocking agents (NMBA) are used?
A
1 in 8000
(if none used - 1 in 136000
15
Q
incidence of awareness in obstetrics and cardiothoracics?
A
- Incidence in obstetrics = 1 in 670
- Incidence in cardiothoracics = 1 in 8600
16
Q
List two drugs associated with increased risk of AAGA.
A
- Thiopentone
- Neuromuscular blocking agents (e.g., rocuronium)
- TIVA
17
Q
Why is TIVA associated with increased awareness?
A
- Tissue cannulas/detached cannula/not visible
- Pump failure/syringe change
- Wrong programme/details inserted
- Lack of training
- No end-tidal monitoring/no direct measurement of anaesthetic agent
- Individual variability in pharmacokinetics
18
Q
Why are NMBA associated with awareness?
A
Incorrectly administered or inadequate reversal.
19
Q
Why is thiopentone implicated in AAGA
A
- Unfamiliarity with its use
- Used in obstetrics – quick induction to knife
- Misplaced for other drugs e.g. Abx
20
Q
Why is RSI associated with increased awareness
A
- Emergency surgery – short time between induction and operating
- Fixed drug doses , no time for titration
- Intubation shortly after drug given
21
Q
What are the patient factors associated with increased risk of AAGA?
A
- Female
- Young
- Anxious
- Difficult airway
- Obesity - drug dosing and difficult airway
- Previous awareness
- Sick patients - lower doses of drug given
22
Q
List surgical factors associated with AAGA.
A
- Obstetrics (especially emergency C-section)
- Cardiac surgery
- Thoracics
- Neurosurgery
23
Q
what aspects of cardiac and thoracic surgery may be linked to increased risk of awareness?
A
thoracics = o NMBA used, switching ET tubes (single and double lumen) and lack of volatile in this period , rigid bronchoscopy – very stimulating and pauses in anaesthetic
cardiac = high opiate low induction agent technique, bypass
24
Q
List two organizational factors for increased AAGA.
A
- Out of hours
- Junior anaesthetist
- emergency surgery
25
What types of monitoring can help reduce awareness risk?
* NMBA/TOF monitoring
* End-tidal anaesthetic gas monitoring
* BIS/Raw EEG / somatosensory /auditory evoked potentials
* TIVA pump effect site concentration monitoring
* AABGI monitoring
* Clinical monitoring - presence of anaesthetist, sweating, eyelash reflex , lacrimation
26
List four possible consequences to a patient of AAGA.
* Immediate/delayed recall or implicit awareness
* Experiences may be auditory, tactile inc pain, awareness of paralysis
* Distress leading to PTSD
* Impact on personal/social life
* Avoidance of future medical care/surgery
27
Define explicit awareness.
Conscious recall of events.
28
Define implicit awareness.
No conscious recall of events but information processed on a subconscious level.
29
List two characteristic findings of asthma on lung function testing.
* Reduced FEV1
* Reduced FEV1/FVC ratio (< 70%)
* Reversible after bronchodilators fiven
* Variable peak exp flow readings
* Positive direct bronchial challenge test
30
Give two possible non-pharmacological reasons for poor asthma control.
* Exposure to allergens/triggers
* Smoking
* Comorbidities (e.g., obesity, reflux)
* Viral infection
31
List three steps to optimize asthma control pre-operatively.
* Avoid allergens if possible
* Stop smoking
* Encourage weight loss
* Involve GP/respiratory physician - optimise meds e.g. steroid inhaler
* breathing exercise programme
32
During surgery, what are four possible causes of acute rise in peak airway pressures apart from bronchospasm?
* Pneumoperitoneum displacing diaphragm
* Pneumothorax
* Endobronchial intubation
* Mucus plug in tube/lungs
* Aspiration
* Pulmonary oedema
33
List three triggers for intraoperative bronchospasm.
* Pre-operative respiratory tract infection
* Airway irritants (cold non-humified gases)
* Histamine releasing drugs (e.g., atracurium, morphine)
- cholinergics – neostigmine
- vagal stimulation – peritoneal stretch
34
List three IV drugs and their bolus doses used in management of intraoperative bronchospasm.
* MgSO4 2-4g IV
* Salbutamol 250mcg IV
* Aminophylline 5mg/kg
* Ketamine 20mg
* Hydrocortisone 200mg
35
List three immediate approaches to ventilation to avoid barotrauma.
* Reduce volumes/switch to pressure control ventilation
* Increase expiratory time via I:E ratio
* Allow permissive hypercapnia
36
What factors have increased the prevalence of asthma in developed countries over the last 20 years?
* Better identification
* Hygiene hypothesis
* Obesity
* Urbanization
* Increased use of triggering drugs (NSAIDs, aspirin, B-blockers)
37
How would you recognize aspiration on SAD?
* Gastric content visible in oropharynx/tubing of SAD
* Hypoxia, increased pressures/bronchospasm, abnormal auscultation
* Tachycardia
38
What would be the immediate management for aspiration under anaesthesia?
* Declare incidence, call for help
* Remove SAD
* Suction airway
* Head down position if still vomitting
* Ventilate with 100% via bag-mask ventilation
* Deepen anaesthesia, give NMBA
* Perform endotracheal intubation
later management:
- Early bronchoscopy if particulate matter aspirated
- Decision to Continue with surgery – depending on severity
- Extubation / continue intubation on ICU - depending on severity
- CXR / ABG
- High index of suspicion for pneumonia and treat early – prophylaxis not recommended
- Incidence reporting
39
List two patient risk factors for aspiration under anaesthesia when using SAD.
* Hiatus hernia/frequent reflux
* Raised intra-abdominal pressure (e.g., obesity, late pregnancy)
- Intra abdominal pathology – bowel obstruction, ileus
- Delayed gastric emptying – diabetes , pain
40
List two anaesthetic risk factors for aspiration when using a SAD.
* Gastric insufflation during bag-mask ventilation
* Poorly seated SAD/wrong size
- Poorly seated SAD/ wrong size
- First generation device
- Light plane of anaesthesia – induction / emergence
41
List four complications that may develop over the next 48 hours after aspiration.
* ARDS
* Chemical pneumonitis
* Lobar collapse
* Type 1/2 respiratory failure
* Atelectasis
(pneumonia later)
42
List four approaches to reduce volume/acidity of gastric contents pre-operatively.
* Metoclopramide
* Sodium citrate/PPI
* Following fasting guidance
* Nasogastric tube and drainage
43
List two physiological mechanisms that help protect against aspiration.
* Lower oesophageal sphincter tone
* Upper oesophageal sphincter tone
* Protective laryngeal reflexes
44
List two indications for performing point of care gastric USS.
* Delayed gastric emptying (e.g., gastroparesis, acute pain, opioids)
* Uncertain fasting status - congitive dysfunction, language barrier
45
What are antral volumes in fasted and non-fasted patients estimated by gastric USS?
* Fasted patient <1.5ml/kg
* Non-fasted patient >1.5ml/kg
46
List factors contributing to adverse airway events with SGA device.
* Poor patient selection - obese, non fasted, reflux
* Suboptimal technique - malposition and poor seal
* Prolonged use of SGA device
* Lack of experience or supervision
47
List common adverse outcomes of SGA.
* Mostly related to aspiration
* Hypoxia from inadequate ventilation
48
Describe the pathophysiology underlying malignant hyperthermia (MH).
* Autosomal dominant condition caused by mutation in ryanodine receptor leading to uncontrolled release of calcium from sarcoplasmic reticulum on exposure to trigger (sux, inhaled agents)
- Uncontrolled muscle contractions result inc tetany – anaerobic, muscle cells death
- High lactate, K+, myoglobin , high CO2, hyperthermia
49
List two anaesthetic triggers for malignant hyperthermia.
* Succinylcholine
* Inhaled anaesthetic gases (e.g., sevoflurane)
50
List three early clinical features of MH in an anaesthetised patient that would initiate treatment.
* Unexplained hyperthermia
* Unexplained high EtCO2
* Unexplained tachycardia
51
What is the management of malignant hyperthermia?
* Call for help
* Get MH treatment pack
* Eliminate trigger (turn off sevo, switch to TIVA, switch circuit, charcoal filtrer, 100% O2 high flow, hypervent)
* Treat with dantrolene 2-3 mg/kg, repeat 1mg/kg until CO2 < 6kpa and temp < 38.5
* Support with active cooling, invasive BP monitoring
* treat complications - hyperkalaemia, acidosis, aki
* report to MH leeds investigation unit
52
List five later onset features of MH that may require further treatment.
* Muscle rigidity
* DIC
* Renal failure
* Arrhythmias
* Metabolic acidosis
* Hyperkalaemia
* compartment sydnrome
53
What are two methods for diagnosing MH following recovery?
* Muscle biopsy - invitro contracture test (halothane and caffeine)
* Genetic testing
54
List three patient groups who should be assessed for possible increased risk of MH prior to elective anaesthesia.
* Patients with personal or family history of episode that may be MH
* Patients with known blood relatives with MH
* Patients with unexplained exertional heat illness
- Patients with clinical myopathy and genetic aetiology implicated in MH susceptibility
- Patients with unexplained recurrent rhabdomyolysis of unknown cause
55
differentials for MH
sepsis, thyroid storm, serotonin syn
56
List five implications of a wrong sided nerve block.
* Potential adverse effects of unnecessary block
* Bilateral block contraindications e.g. interscalene
* Exceeding safe doses of LA
* Wrong sided surgery
* Loss of trust
* delayed discharge due to b/l leg weakness
57
State why the 'stop before you block' changed to 'prep stop block'.
Changed to improve safety further.
The stop before block lacked success in reducing rates of wrong side blocks due to flexibility in when performed
58
List four recommendations by PREP STOP BLOCK.
* Preparation by blocker - preps equiptment, positions, cleans site, sterile glove
* Stop just before blocking with assistant's help - consent form and arrow
* Block immediately after
* Restart process if delays occur / multiple blocks
59
Apart from failure of using SBYB, list five factors that can increase the risk of wrong sided block.
* Long duration of WHO sign in
* Patient being prone/lateral
* Busy anaesthetic room/distraction
* Changes to list
* More than one block being performed
- Surgical mark absent or covering of the site e.g. with blankets
* time pressures
60
Define the term 'never event'.
A serious incident that is wholly preventable due to available guidance or safety recommendations on a national level that provide protective barriers that should be implemented by health care providers
61
List 4 drug-related never events.
* Wrong route of administration of a drug
* Overdose of insulin due to abbreviations or incorrect device
* Overdose of methotrexate
* Use of air rather than oxygen in someone requiring oxygen
- mis selection of strong potassium containing solution
- misselection of high dose midazolam during conscious sedation
62
list non drug related never events
- wrong sided surgery
- wrong implant
- retained foreign object post surgical closure
- transfusion of ABO incompatible blood
- misplaced nasogastric tube
- chest or neck entrapment in bed rails
63
What are 2 pieces of information from patient pre-op that can help reduce IV drug errors?
* Height and weight of patient
* Allergies
* drug hx / PMH
64
State 4 behavioral factors which may contribute to anaesthetic IV drug errors.
* Distraction from a busy theatre environment, teaching, 2 tasks at once
* Cognitive overload during complex calculations
* Anxiety or tiredness
* Lack of teamwork and communication - failure to ask for support, poor handover/communication
* lack of knowledge / familirity with the drug
65
List 4 environmental factors which may contribute to IV drug error.
* Cluttered workspace
* Low light levels
* Drugs placed in wrong boxes
* Noisy environment/distractions
- drugs with similar packaging
- more than 1 anaesthetist drawing up medications
- lack of labelling
- availability of drugs required to be diluted e.g. metaraminol 20mg in 1 ml
66
Outline 4 organizational strategies that may minimize IV drug errors.
* Standardized infusion/dilutions
* Tray for emergency vs normal medications
* Drug label with colored labels
* Pre-made syringes for emergency drugs
- ampuoles containing normal doses of medications
- flush lines before leaving theatre
- use of NR fit equipment to prevalent accidental IV of local
- putting unused ampoules in correct box
67
What are 3 important aspects of responding to anaesthesia-related IV drug error after care has been completed?
* Datex/incident reporting
* Duty of candor to the patient
* Discussion at M&M meetings
* team debief / personal reflection
* regular audits / QIPs
68
List 4 anaesthetic factors that may predispose to perioperative dental damage.
* Difficult intubation
* Limited mouth opening
* Vigorous suctioning
* laryngoscopy
* Forceful removal of airway
* use of double lumen ET tube
* LMA use
69
List 5 dental factors that predispose to perioperative dental damage.
* Poor dentition
* Loose tooth
* Prominent upper incisor
* Crowns and caps
* Isolated teeth
* infant teeth
* > 50 yrs
70
State 4 aspects of initial management if a front tooth is missing after intubation.
* Assess for possible airway compromise
* Locate missing tooth and inspect oral cavity - may need CXR. remove with foreceps if possible
* Reimplant tooth if intact
* If not, place in saline or milk until urgent discussion with dentist
71
Describe action after an acute situation involving dental damage.
* Written referral to dentist
* Duty of candor discussion
* Datex/incident form
* Adequate analgesia for dental damage
72
Suggest 4 strategies to avoid dental damage in high-risk patients.
* Avoid GA if possible
* Refer for pre-op dental treatment
* Stabilise loose teeth pre-op
* Use dental guards
* avoid laryngoscopy - nasal fibreoptic
* soft bite block
73
What is anaphylaxis?
Life-threatening allergic reaction, Type 1 hypersensitivity reaction
74
List the 4 most common triggers for perioperative anaphylaxis according to NAP 6.
* Antibiotics - teic and co-amox
* Neuromuscular blocking agents
* Chlorhexidine
* Patent blue dye
75
What is the estimated incidence of perioperative anaphylaxis?
1 in 10,000
76
Outline the pathophysiological process of IgE mediated anaphylaxis.
* Sensitization event leads to IgE antibodies
* Second exposure triggers mast cell degranulation
* Release of histamine and cascade of immune mediators causes symptoms
77
What is the most common presenting feature of anaphylaxis in NAP 6?
Hypotension
78
Give 3 other possible presenting features of perioperative anaphylaxis.
* High airway pressures/bronchospasm
* Tachycardia
* Angioedema
79
Give 2 indications for the initiation of chest compressions in case of anaphylaxis.
* BP < 50mmHg systolic
* Cardiac arrest
80
Give 4 IV pharmacological options for treatment of hypotension in anaphylaxis with bolus doses.
* Adrenaline 50mcg
* Glucagon 1mg if beta blocked
* Metaraminol 0.5mg
* Vasopressin 2 units
* norad infusion
* fluid bolus 20ml/kg
81
What is the dosing of adrenaline in anaphylaxis?
IV 50 micrograms for adults, IM 0.5mg
82
What are the timings for taking tryptase samples after an anaphylaxis event?
* As soon as patient stable
* 1-2 hours after event
* 24 hours after
83
after initial management of anaphylaxis resolved in theatre, what next?
ITU - biphasic
yellow card scheme
- Anaesthetists responsibility to inform GP, patient, department and refer for immunological testing
84
What is the management protocol for needle stick injury?
Wash immediately with soap and water, encourage bleed, dry and cover wound
- Occupational health / if out of hours – ED
- Risk assessment completed – ask patient to have their bloods taken
- Datex
- Depending on likelihood of BBV may receive prophylaxis for HIV / hep B
85
What are the transmission rates for bloodborne viruses after a needle stick injury?
* HIV = 0.3%
* Hep C = 3%
* Hep B = 30%
86
What are the classic signs of pneumothorax in theatre?
* High pressures
* Low volumes
* Low BP
* High HR
87
causes of hypoxia in anaesthesia
- A = ET tube disconnected
- B = inadequate FiO2, MV, resp causes (bronchospasm, hypovent, shunting, pneumothorax, aspiration
- C = low perfusion P.E/ hypotension
- D = increased consumption – MH/ sepsis
- Other – sats probe disconnected
88
how is a high spinal managed?
- Support ventilation
- Reassurance
- Glycopyrrolate / atropine
- Metaraminol/ ephedrine
- Raise legs /not back
- Put to sleep and intubate
89
How can a pneumothorax be diagnosed in theatre?
* CXR
* Thoracic USS showing lung point sign
90
What are the risk factors for pneumothorax in theatre?
* Pre-existing lung disease
* Central lines
* High airway pressures
* Smoking
- Previous pneumothorax
- Connective tissue diseases
- Brachial plexus blocks
91
What are the landmarks for needle decompression of tension pneumothorax?
2nd intercostal mid clavicular line
92
landmarks for a chest drain insertion...
- Pectoralis major, latissimus dorsi, base of axilla, 5th intercostal space
93
How to differentiate LAST from high spinal?
* LAST: agitation, metallic taste, loss of consciousness
* High spinal: hypotension, bradycardia, apnoea
94
What is the dose of intralipid in LAST?
20% intralipid 1.5ml/kg bolus + infusion 15ml/kg/hr
- Can repeat x3 bolus and increase infusion to 30ml/kg/hr
- Max dose 12ml/kg
95
What are the clinical features of a venous air embolus?
* Low BP
* High HR
* Low EtCO2
* Neuro symptoms
wind mill murmur
96
How is a VAE managed?
- Immediately inform surgeons so they can flood wound and compress
- Turn off N20 if using
- Switch to TIVA – inhaled anaesthetics cause loss of hypoxic vasoconstriction so reduced extreation of air
- Increase venous pressure – head down and PEEP
97
What is the gold standard diagnosis for VAE?
Transoesophageal echo
98
How is cardiac ischaemia during anaesthesia recognized?
Change in ECG: ST elevation, depression, T inversion
99
what are the risk factors for VAE?
- CVC
- Laparoscopic surgery
- Hypotension
- H&N surgery
100
How is cardiac ischaemia during anaesthesia managed?
- Increase FiO2, call for senior support
- A to E – optimise BP and O2 – may be reversible
- 12 lead ECG and CM5 configuration
- GTN infusion If BP stable
- B blockers if tachycardia
- 300mg Aspirin rectally
- Bloods -troponins
- HDU and cardio referral – may need PCI
