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Year 3 Anaesthetics > Intra-operative > Flashcards

Intra-operative Flashcards

1
Q

Why starve patients prior to surgery?

A

Reduce the risk of aspiration

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2
Q

What is the difference between group and save and crossmatch?

A

Group and save is when a blood type is identified and held, pending crossmatch if required. Crossmatch is when the blood type is identified and actually allocated to a patient.

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3
Q

How should you record the use of controlled drugs peri-operatively? (x5)

A

The dose, form and strength. The total quantity or dosage units of the preparation in BOTH words and figures. For instalment prescriptions (describes dosage intervals e.g. 10mcg/4hours), specify the instalment amount and instalment interval.

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4
Q

What are controlled drugs?

A

Mostly concerns strong opiates and amphetamine-like stimulants used for ADHD. They are controlled usually because they can be abused or cause addiction.

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5
Q

What are the ‘Five Steps to Safer Surgery’?

A
  1. Briefing: introduce team, their order in the surgical list, and concerns relating to staff, equipment, surgery and anaesthesia.
  2. Sign in: confirm patient/procedure/consent form, allergies, airway issues, anticipated blood loss and machine checks before induction of anaesthesia
  3. Timeout: before the start of the surgery, team member introduction, verbal confirmation of patient information, thromboprophylaxis, discuss surgical/anaesthetic issues.
  4. Sign out: before staff leave the theatre, confirm recording of procedure – instruments, swabs, and sharps correct, specimens correctly labelled, equipment issues addressed, post-operative management discussed and handed over.
  5. Debriefing: at the end of the list – evaluate the list, learn from incidents and remedy problems.
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6
Q

What is the WHO Surgical Safety Checklist?

A
  1. NOTE that it is Trust-specific. SIGN IN: BEFORE INDUCTION OF ANAESTHESIA. Led by anaesthetist; identify patient and verify consent, confirm surgery, check medication and equipment, review allergies and airway
  2. TIME OUT: BEFORE SKIN INCISION. Led by Surgeon. Make sure everyone introduces themselves, confirm patient details, comment on duration of operation, expected blood loss and special equipment needed, state ASA grade, confirm equipment sterility and discuss prophylaxis (VTE, abx), glycaemic control and patient warming.
  3. SIGN OUT: BEFORE THE PATIENT LEAVES THEATRE. Led by anaesthetist. Confirm swabs and instruments used, confirm correct procedure performed, analgesia/antibiotics/VTE prophylaxis prescribed, highlight concerns.
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7
Q

What is the purpose of the WHO Surgical Safety Checklist?

A

Ensures pre-operative preparation, intra-operative monitoring and post-operative review

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8
Q

What are the different airway adjuncts/devices used peri-operatively? (x4) What are their indications?

A
  • Oropharyngeal airway (Guedel): maintain a patent airway. Indicated for unconscious breathing patients
  • Bag-valve mask: used in respiratory failure when a patient’s breathing is insufficient, or in respiratory arrest when breathing has ceased completely (apnoea). This creates a positive pressure for air entry. Oxygen reservoir allows for greater FiO2 (fraction of inspired)
  • ET tube: to intubate a patient. Secure a DEFINITVE airway that prevents aspiration risk
  • LMA (laryngeal mask airway/supraglottic airway/i-gel): not a definitive airway but used for airway maintenance during low-risk surgery
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9
Q

What is the anatomy of an ET tube?

A

Black markers tell you roughly where you should be against the vocal cords (in between black lines). Bevel tip contains Murphy’s eye (back-up hole if tip becomes occluded), markers indicate depth of insertion. Inflation cuff distally to secure airway.

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10
Q

What is the anatomy of a supraglottic airway?

A

PROXIMAL END: 15mm connector for catheter and end of gastric channel. The black line is a position guide for confirmation of insertion depth. MIDDLE PORTION: bite block (reduces the possibility of airway channel occlusion). DISTAL PORTION: epiglottic rest and non-inflatable cuff and distal end of gastric channel.

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11
Q

What is the purpose of the gastric channel in an LMA?

A

Allows for suctioning, passing of a NG tube, and facilitates venting.

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12
Q

What is the purpose of the epiglottic rest in an LMA?

A

Reduces the possibility of epiglottis ‘down folding’ and airway obstruction.

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13
Q

How do you size a Guedel?

A

Sizing is from angle of mandible to the side of the mouth.

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14
Q

How do you insert a Guedel?

A

Position in opposing direction to pharynx, and rotate across roof of mouth as you insert.

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15
Q

How do you insert an ET tube?

A

Use a laryngoscope to lift the tongue (lift the laryngoscope; do not adjust its angle or you risk breaking teeth) and visualise the airway. Visualising the vocal cords, insert the ET tube so that the two black lines fall either side of the vocal cords. Inflate the cuff with air (typically 10ml).

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16
Q

What can you use to assist with ET tube insertion?

A

Bougie

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17
Q

How do you use a bag-valve mask?

A

Do not squeeze bag fully – only 1/3rd AND slowly. Mimic your own breathing. Jaw thrust the mouth INTO the mask (not mask into mouth), and grip mask to create a full seal.

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18
Q

How do you insert an LMA?

A

Lubricate the posterior surface of the LMA. Flex the neck, lift chin and open mouth. Insert device and manually guide down the hard palate of the mouth until you reach the laryngeal inlet. Be aware of the tongue folding back.

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19
Q

How do you check for correct ET tube insertion? (x4)

A

Misty tubing, chest rising and falling, capnography shows breathing, cannot hear escaping air.

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20
Q

What is the risk of ET tube insertion?

A

Can cause trauma especially with cuff inflation.

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21
Q

Differentiate between indications for LMA and ET tube.

A

ET tube indicated in complicated patients such as elderly, obese and long procedures where you want to ensure that the airway is definite. Also in pronated surgery. Otherwise, igel preferred.

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22
Q

What is the importance and mechanism of preoxygenation prior to anaesthetic induction?

A

We pre-oxygenate patients on 100% oxygen so they can build a reservoir in their body. Our body uses 250mlO2/min. When we preoxygenate, we give patients up to 5L reservoir of O2, meaning they can remain on 100% saturation despite apnoea for up to 20 mins while we intubate.

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23
Q

When should you be more conservative with pre-oxygenation?

A

In gynae and ear surgeries, because bagging a patient has high incidence of N&V from pumping air into stomach.

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24
Q

How would you deal with bronchospasm outside of theatre (asthmatics)?

A
  • Acronym: O SHITMS
  • O2 – high flow O2 and gain IV access
  • Salbutamol – nebulised, 2.5-5mg
  • Hydrocortisone – 100mg IV 6-hourly or prednisolone orally 40-50mg/day
  • Ipratropium – nebulised 0.5mg (4-6 hourly) + IV salbutamol if not responding (250 mcg slow bolus then 5-20 mcg/min)
  • Theophylline/Aminophylline
  • Magnesium 2g IV over 20 minutes
  • In extremis (decreasing consciousness or exhaustion): adrenaline; nebulise 5 ml of 1 in 1000. IV 10 mcg (0.1 ml 1:10000) increasing to 100 mcg (1ml 1:10000)
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25
Q

What does perioperative mean?

A

From the point of CONSIDERATION of surgery, to FULL RECOVERY.

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26
Q

What are the recommendations for medication administration perioperatively for asthmatics? (x7)

A
  • B2 agonists e.g., Salbutamol: convert to nebulised form
  • Anticholinergic drugs e.g., Ipratropium: convert to nebulised form
  • Inhaled steroids e.g., budesonide: continue inhaled formulation
  • Oral steroids e.g., prednisolone: continue as IV hydrocortisone until taking orally (1mg prednisolone = 5mg hydrocortisone)
  • Leukotriene inhibitor e.g., Montelukast: restart when taking oral medications
  • Mast cell stabiliser e.g., Disodium cromoglycate: continue by inhaler
  • Phosphodiesterase inhibitor e.g., aminophylline: continue where possible
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27
Q

How do you recognise anaphylaxis?

A
  • A – airway swelling such as throat and tongue, hoarse voice and stridor
  • B – SOB, wheeze, patient becoming tired, confusion from hypoxia, cyanosis (late sign), respiratory arrest
  • C – signs of shock (pale, clammy), tachycardia, hypotension, decreased levels of consciousness, cardiac arrest (if unmanaged)
  • D&E – itching, diarrhoea, vomiting, erythema, urticaria, oedema
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28
Q

How is anaphylaxis managed?

A
  1. Lie flat and raise legs
  2. Adrenaline given IM; repeat after 5 mins if no better
  3. THEN Establish airway with high flow oxygen
  4. IV fluid challenge
  5. Chlorphenamine
  6. Hydrocortisone
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29
Q

How do you monitor anaphylaxis management? (x3)

A

Pulse oximeter, ECG and blood pressure.

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30
Q

Dosing of adrenaline in anaphylaxis?

A

500 micrograms IM (0.5mL) (1:1000 adrenaline). Less for children under 12.

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31
Q

What should you use in IV fluid challenge? Amounts?

A

500-1000mL colloid in adults. 20mL/kg in children.

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32
Q

Dosing of Chlorphenamine in anaphylaxis?

A

IM or slow IV – 10mg; 5mg for 6-12yrs; 2.5mg for younger.

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33
Q

Dosing of Hydrocortisone in anaphylaxis?

A

200mg for adult, 100mg for 6-12yrs, 50mg for younger.

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34
Q

What is secondary pneumothorax?

A

From underlying lung disease or smoker and over 50.

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35
Q

What is the management for pneumothorax?

A

Depends on whether primary or secondary, tension, size and symptoms: Tension pneumothorax is managed first with needle aspiration until a chest tube can be placed. Then insert a chest drain (tensioning will reoccur if you remove the cannula used for aspiration).

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36
Q

How is a chest drain inserted?

A

Into the safe triangle: lateral border of pec major, anterior border of latissimus dorsi, horizontal level of nipple and axilla.

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37
Q

What should you watch out for in chest drainage of pneumo/haemothorax? (x4)

A

Retrograde flow back into the chest, persistent bubbling (there may be a continual leak from the lung), blockage of the tube from clots/kinking, mispositioning.

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38
Q

How is aspiration of a pneumothorax done?

A

2nd intercostal space, MCL OR 4-6th intercostal space MAL. Insert cannula, remove needle and connect to a 50mL syringe with a 3-way tap. Aspirate up to 2.5L of air – the syringe with saline acts as the water seal.

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39
Q

What is the difference between an open, closed and tension pneumothorax?

A

TENSION – air is drawn into the intrapleural space with each breath but cannot escape due to a valve-like effect of the tiny flap in the parietal pleura. The increasing pressure embarrasses the heart and other lung. OPEN – from ruptured bleb and visceral pleura allowing air entry into pleura from lung. CLOSED – trauma punctures parietal pleura. NB when a tension is managed with a cannula, it becomes an OPEN pneumothorax. See photo.

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40
Q

What is done post-pneumothorax management?

A

CXR to check that pneumothorax has resolved.

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41
Q

How is haemothorax managed?

A

Needle aspiration followed by chest drain insertion.

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42
Q

Where are chest drains inserted?

A

6th ICS, MAL.

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43
Q

What is capnography?

A

Measure of partial pressure of CO2 in respiratory gases, usually presented as a graph of expired CO2 in mmHg plotted against time.

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44
Q

What are the normal ranges for inspired and expired CO2?

A

35-45mmHg expired; 0mmHg inspired.

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45
Q

What is the normal range for pulse oximetry?

A

95-100%.

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46
Q

What is the normal range for pulse oximetry in COPD patients?

A

88-92%.

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47
Q

What are the pH normal ranges for arterial and venous blood gas?

A

7.35-7.45; 7.31-7.41

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48
Q

What are the paO2 normal ranges for arterial and venous blood gas?

A

80-100; 35-40mmHg

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49
Q

What are the PaCO2 normal ranges for arterial and venous blood gas?

A

35-45; 41-51 mmHg.

50
Q

What are the SaO2 normal ranges for arterial and venous blood gas?

A

95%; 70-75%

51
Q

What are the HCO3- and BE normal ranges for arterial and venous blood gas?

A

22-26 mEqL^-1 for HCO3- arterial and venous; -2 to +2 for BE arterial and venous.

52
Q

What is the physiological control of breathing?

A
  • Peripheral chemoreceptors in the aortic and carotid bodies detect changes in oxygen and carbon dioxide concentrations
  • Central chemoreceptors in the medulla oblongata are sensitive to changes in pH in the blood, primarily (which changes according to changes in CO2).
  • Vagal and glossopharyngeal inputs detect changes from pulmonary stretch receptors.
  • There are four respiratory groups in the respiratory centre:

o Dorsal (posterior) respiratory group – medulla. Involved in inhalation.

o Ventral respiratory group – medulla. Contains pre-Botzinger complex. Controls forced expiration and increases force of inhalation. Regulates rhythm.

o Pneumotaxic centre – nuclei in the pons. Coordinates speed of inhalation and exhalation and sends inhibitory impulses to inspiratory area. Pneumotaxic centre is activated when a faster rate of breathing is needed. It overrides the apneustic centre.

o Apneustic centre – nucleus in the pons. Coordinates speed of inhalation and exhalation and sends stimulatory impulses to inspiratory area. Apneustic breathing describes deep, gasping inspiration followed by brief, insufficient exhalation.

  • The pons respiratory centres are collectively called the pontine respiratory group.
  • The respiratory centre controls the rate and depth of breathing.
53
Q

What is the primary driver of breathing?

A

CSF pH.

54
Q

What are the triggers for blood transfusion? (x4)

A
  • Hb below 70 g/L. Be less confident if patient is elderly, has significant cardiorespiratory comorbidities or inadequate tissue oxygenation
  • Hb below 90 g/L and severe sepsis
  • Hb below 90 g/L and neurological injury
  • Hb below 90 g/L and ischaemic heart disease
55
Q

How much fluid is required if cannot be given orally?

A

2-2.5L per day, containing 70mmol Na+ and 70mmol K+. Sick patients need more as they have larger fluid loss through drains, fevers, diarrhoea.

56
Q

What is the difference between crystalloids and colloids?

A

CRYSTALLOIDS: Aqueous solutions of mineral salts including 0.9% normal saline. COLLOIDS: contain larger insoluble molecules.

57
Q

What examples are there of crystalloids and what do they do? (x2)

A

0.9% saline which is isotonic with plasma (same Na+ content as plasma of 150mmol/L; used for hydration and hypovolaemia), 5% glucose (liver metabolises the glucose leaving only water, which rapidly equilibrates throughout all extra and intracellular fluid compartments and is therefore useless in fluid resuscitation as only 1/9 will remain in intravascular space).

58
Q

What is a key characteristic of colloids and why are they used?

A

High osmotic content similar to that of plasma and therefore remain in the intravascular space for longer than other fluids, making them appropriate for fluid resuscitation.

59
Q

In reality, what fluids are used in fluid resuscitation?

A

0.9% saline AND colloids are used TOGETHER.

60
Q

What are the disadvantages of colloids? (x2)

A

Expensive and can cause anaphylactic reactions.

61
Q

What are the indications for invasive monitoring of blood pressure? (x3)

A

Haemodynamically unstable patients, when patients are undergoing frequent blood gas measurements, or end-organ disease requiring precise pressure regulation.

62
Q

What happens to blood pressure intraoperatively?

A

FALLS because of venous dilation, reduced venous return and subsequent reduced CO.

63
Q

How do you manage intra-operative hypotension?

A

Alpha1 agonists such a Metaraminol as these constrict veins. Increasing HR won’t do that much.

64
Q

Complication of aortic stenosis in anaesthetics?

A

Patient cannot increase CO as their aortic valve is stenosed, so under anaesthesia, their BP will fall, and their CO will not be able to compensate for this. Instead, we need to put emphasis on increasing TPR with a1 agonists. Remember, BP = CO x TPR.

65
Q

What is the WHO pain ladder?

A
  • Stage 1: Non-opioid e.g., aspirin, paracetamol or NSAID +/- adjuvant
  • Stage 2: (when pain persisting or increasing) Weak opioid e.g., codeine +/- non-opioid, +/- adjuvant
  • Stage 3: (when pain persisting or increasing) Strong opioid e.g., morphine +/- non-opioid, +/- adjuvant
66
Q

What is the approach to acute pain management? (x6)

A
  • Identify and treat the underlying pathology wherever possible
  • Give regular doses rather than as required
  • Choose the best route: PO, PR, IM, epidural, SC, inhalation, IV
  • Explanation and reassurance contribute to analgesia
  • Allow the patient to be in charge. This prevents overuse
  • Liaise with the Acute Pain Service if possible
67
Q

What are the indications for paracetamol? (x2)

A

Pyrexia and mild pain.

68
Q

What is the dosage and mode of administration of paracetamol? (x2)

A

ORAL: 0.5g-1.0g/4h (up to 4g daily). IV: 15mg/kg/4h IV; dose administered over 15 mins; maximum 60mg/kg/day.

69
Q

When should you be cautious with paracetamol dosing in patients?

A

Hepatotoxicity – patients with liver impairment. NOT a contraindication.

70
Q

What is the dosage and mode of administration of NSAIDs?

A

ORAL: 400mg/8hr

71
Q

What are the indications for NSAIDs? (x4)

A

Pain and inflammation in rheumatic disease, mild-moderate pain, post-operative analgesia, pyrexia.

72
Q

What are the contraindications for Ibuprofen? (x3)

A

Peptic ulcer, clotting disorders, anticoagulants.

73
Q

When should you be cautious with ibuprofen dosing in patients? (x6)

A

Asthma, renal or hepatic impairment, heart failure, IHD, pregnancy and the elderly.

74
Q

What are the contraindications for aspirin?

A

What are the contraindications for aspirin?

75
Q

What is the dosage and route of administration for morphine?

A

10-15mg/2-4hr IV/IM.

76
Q

What is the dosage and route of administration for diamorphine?

A

5-10mg/2-4hr PO, SC or slow IV, but you may need much more.

77
Q

How do you dose Naloxone to recover patients from opioid overdose?

A

100-200mcg IV, followed by 100mcg increments e.g., every 2 mins until responsive.

78
Q

What are the side-effects of opioids?

A

Nausea (so give with anti-emetic), respiratory depression, constipation, cough suppression, urinary retention, decreased BP, sedation.

79
Q

When are opioids contraindicated?

A

Head injury and hepatic failure.

80
Q

What should you be cautious of with regional (epidural) anaesthesia/analgesia? (x2)

A

Respiratory depression and local anaesthetic autonomic blockade (reduced BP).

81
Q

What are adjuvant analgesics?

A

Primary function is not analgesics and can be used to treat the associated symptoms of pain e.g., NSAIDs, antidepressants, anticonvulsants e.g., pregabalin.

82
Q

What are the principles of multimodal analgesia? Drugs involved? (x4)

A

Multiple analgesics with different modes of action. The drugs involved are combined on the basis of patient’s experience of pain: (1) NON-OPIOIDS: the post important background medication and improves the quality of analgesia when combined with opioids; (2) OPIOIDS: relief of severe pain; (3) LOCAL ANAESTHETICS; (4) ADJUVANTS: ketamine is well-known and used to treat acute pain which otherwise responds poorly to opioids including neuropathic pain.

83
Q

What is the dose and route of administration for Ondansetron (anti-emetic)?

A

4-8mg (TDS – latin for three-times daily), PO/IV.

84
Q

What is the dose and route of administration for Cyclizine (anti-emetic)?

A

50mg TDS, PO/slow IV/IM

85
Q

What is the dose and route of administration for Dexamethasone (anti-emetic)?

A

4-8mg BD (twice daily), IV.

86
Q

What is the dose and route of administration for Metocopramide (anti-emetic)?

A

10mg TDS, PO/IV.

87
Q

What is the dose and route of administration for Prochlorperazine (anti-emetic)?

A

12.5mg BD, IM.

88
Q

What are the indications and contraindications of Ondansetron?

A

Post-operative and cytotoxic N&V such as chemo/radiotherapy. CI: Congenital long QT syndrome as this is a side-effect.

89
Q

What are the indications and contraindications of Cyclizine? (x3 and x4)

A

Motion sickness, morning sickness, opioid nausea. CI: epilepsy, glaucoma, neuromuscular disorders, heart failure, because Cyclizine is anti-cholinergic and causes tachycardia.

90
Q

What are the indications and contraindications of Dexamethasone? (x2 and x2)

A

Perioperatively and with other antiemetics in cytotoxic N&V. CI: immunosuppressed, fighting a systemic infection.

91
Q

What are the indications and contraindications of Metoclopramide? (x2 and x4)

A

Cytotoxic and post-operative N&V. CI: after GI surgery, GI haemorrhage, epilepsy, or after GI obstruction/perforation.

92
Q

What are the indications and contraindications of Prochlorperazine? (x5)

A

Cytotoxic and post-operative N&V. CI: CVD (one side-effect is Long QT syndrome), blood dyscrasias, conditions predisposing seizures, depression, diabetes.

93
Q

Why is fentanyl often co-administered with Propofol in anaesthetic induction and maintenance? (x2)

A

(1) Means that you can administer a lower dose of Propofol for sedation. (2) Pain stimulation still occurs when under GA, so fentanyl administration generally reduces the pain response, such as increased HR which would put the patient at risk (particularly if labile).

94
Q

Why is fentanyl a good intra-operative opioid?

A

Fast acting.

95
Q

What is the effect of opioids on ventilation?

A

Respiratory depression by resetting the parameters that drive respiration at a higher paCO2.

96
Q

What makes a patient apnoeic in GA?

A

Combination of both the GA and the opioid.

97
Q

What senses and controls temperature in the body?

A

Controlled by hypothalamus which uses thermoreceptors; one type to respond to cold temperatures and a second type to respond to warm temperatures. Thermoreceptors are also found peripherally and communicates with the hypothalamus to integrate a response and anticipate central changes.

98
Q

What ways can the body warm and cool itself? (x4 and x4)

A

WARM: vasoconstriction (reduce convection and conduction heat loss), piloerection, thermogenesis (body’s muscles, organs and brain produce heat; muscles through shivering), and hormonal thermogenesis (thyroid increases metabolism). COOL: evaporation (sweating), vasodilation (aids convection and conduction heat loss), hair on skin lie flat, and radiation.

99
Q

What are the effects of anaesthesia on thermoregulation? (x2)

A

(1) Anaesthetic-induced vasodilation results in core-to-peripheral redistribution of body hear and decreases core temperature. Subsequently, core temperature decreases as heat loss to environment exceeds metabolic heat production. (2) Anaesthetics (and opioids) reduce the vasoconstriction and shivering thresholds.

100
Q

How can temperature be measured and expected values?

A
  • Pharyngeal probe – around 36.8 degrees.
  • Rectal probe – around 37.5 degrees.
  • Tympanic membrane measurement – around 37.5 degrees.
  • Core temperature can be accurately monitored only through tympanic membrane and invasive methods such as pulmonary artery.
101
Q

What is normal body temperature?

A

36.5-37.5 degrees.

102
Q

What temperature should be aim for intra-operatively?

A

Over 36 degrees.

103
Q

What ways can we warm patients intra-operatively? (x3)

A

Warm air blanket (bear hugger), fluid warmers (warm IV fluids) and heat moisture exchangers (humidify and warm inspired gases).

104
Q

What are the indications for each intra-operative heat-warming measures?

A

Bear huggers should be used in surgeries exceeding 30 minutes. Longer procedure = fluid warmer.

105
Q

What three ways can you assess VTE? (x2)

A

WELLS SCORE, D-DIMER (sensitive but not specific for VTE) and RISK FACTORS (infection, pregnancy, malignancy, thrombophilia, synthetic oestrogen, obesity, past DVT, and post-op).

106
Q

How is the Wells score interpreted?

A

Less than or equal to 1: perform D-dimer. If -ve, DVT excluded. If +ve, USS. More than or equal to 2: do D-dimer and USS. If both -ve, exclude DVT. If USS negative but D-dimer positive, repeat USS in 1 week.

107
Q

When are ted socks contraindicated?

A

Vascular patients because you assume peripheral vascular disease. Ted socks would put pressure on vessels and exacerbate poor perfusion. You can mitigate VTE still by administering LMWH.

108
Q

How do you calculate Wells score? (x10)

A

The following clinical features score 1 point: active cancer, paralysis/paresis(weakness)/recent leg immobilization, recently bedridden for more than 3 days or major surgery in last 12 weeks, local tenderness along deep venous system, entire leg swollen, calf swelling over 3cm compared with asymptomatic leg, pitting oedema, collateral superficial veins, previously documented DVT. -2 points: alternative diagnosis at least as likely as DVT.

109
Q

If you are unsure, how can you test the efficacy of sedation?

A

Flush cannula with acid to check patient is asleep = would usually withdraw with pain.

110
Q

How can you test the efficacy of spinal anaesthesia?

A

Cold spray because relayed by the same C fibres as pain. If they can feel cold spray, they can feel pain.

111
Q

What are the indications for an ART line? (x2)

What do you do once an ART line is inserted to reduce the risk of air emboli?

Aspirate blood into a syringe of saline. The saline is your water seal. Aspirate blood into the saline; then you know you have eliminated all air.

A

CVS unstable patients who need to be closely monitored AND patients with blood disorders for the same reason.

112
Q

What do you do once an ART line is inserted to reduce the risk of air emboli?

A
113
Q

What are the special considerations for CO2 in neurosurgery?

What is combined spinal and epidural anaesthesia (CSE)?

Regional anaesthetic needle-through-needle technique involving introduction of epidural needle into epidural space followed by introduction of long fine spinal needle to enter subarachnoid space. It is used to combine the rapid onset of spinal anaesthesia with the long-lasting analgesia from the epidural catheter.

A

Kept LOW as normal/high CO2 increases cerebral blood flow.

114
Q

What is combined spinal and epidural anaesthesia (CSE)?

A
115
Q

Indications for combined spinal and epidural anaesthesia?

How do you insert an epidural?

Insert needle. You reach the epidural space when there is NO RESISTANCE on saline insertion.

A

When analgesia exceeds period provided by single spinal injection e.g., C-sections.

116
Q

How do you insert an epidural?

A

Insert needle. You reach the epidural space when there is NO RESISTANCE on saline insertion.

117
Q

CSF pulses?

What are the indications for tracheostomy?

Tracheostomies are performed NON-ACUTELY: tumour from larynx cancer (tracheostomy is often permanent and seen in smokers. Larynx is removed and procedure is called laryngectomy. Patients can no longer talk), on ITU

A

Your CSF is pulsatile, which can be seen as a waveform when you insert an epidural with a pressure monitor.

118
Q

What are the indications for tracheostomy?

A

Tracheostomies are performed NON-ACUTELY: tumour from larynx cancer (tracheostomy is often permanent and seen in smokers. Larynx is removed and procedure is called laryngectomy. Patients can no longer talk), on ITU

119
Q

What are the indications for cricothyroidotomy?

When do you suspect airway burns?

Evidence of smoke inhalation, singing of facial hairs, soot in mouth, hoarse voice and stridor from oedema.

Why are tracheostomies used on ITU?

Body becomes deconditioned when on ITU which can affect respiratory muscles. Therefore, while the body recovers and conditions off a ventilator, you can do a tracheostomy (temporarily) so that they are no longer relying on an ET tube and can be awake, not sedated. It moves the patient forward.

A

Performed ACUTELY: oedema e.g., from burns or anaphylaxis, or neurological trauma that results in loss of consciousness (unsafe breathing and swallowing) or neurodegenerative disorders leading to insufficient neurological supply to the intercostal muscles and diaphragm.

120
Q

When do you suspect airway burns?

Why are tracheostomies used on ITU?

Body becomes deconditioned when on ITU which can affect respiratory muscles. Therefore, while the body recovers and conditions off a ventilator, you can do a tracheostomy (temporarily) so that they are no longer relying on an ET tube and can be awake, not sedated. It moves the patient forward.

A

Evidence of smoke inhalation, singing of facial hairs, soot in mouth, hoarse voice and stridor from oedema.

121
Q

Why are tracheostomies used on ITU?

A

Body becomes deconditioned when on ITU which can affect respiratory muscles. Therefore, while the body recovers and conditions off a ventilator, you can do a tracheostomy (temporarily) so that they are no longer relying on an ET tube and can be awake, not sedated. It moves the patient forward.

Year 3 Anaesthetics (4 decks)

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