Resuscitation / Critical Illness

Question 1

Variceal Bleeding

Answer 1

Pantoprazole 80mg stat then 8mg/hr

Ceftriaxone 1g or ciprofloxacin 400mg IV

TXA 1g

Octreotide 50microg IV bolus then 50microg/hr for 48hrs

Terlipressin 2mg IV every 4 hours

Question 2

Massive PE Thrombolysis

Answer 2

Tenectaplase

Wt < 60kg: 6000u = 30mg

Wt 60 – 70kg: 7000u = 35mg

Wt 70 – 80kg: 8000u = 40mg

Wt 80 – 90kg: 9000u = 45mg

Wt > 90kg: 10000u = 50mg

Alteplase

Wt > 65kg 10mg IV bolus then 90mg infusion over 2 hours

Wt < 65kg 10mg IV bolus then 1.5mg/kg (max 90mg) over 2 hours

Question 3

Local Anaesthetic Toxicity

Answer 3

IV Fluids +/- inotropes for hypotension

Midazolam for seizures

Sodium Bicarbonate 1-2mmol/kg every 1-2 minutes for cardiac arrythmia (Na channel blockade) ……… buvipicaine

Intralipid 20% 1.5ml/kg over 1 minute then infusion 0.25 ml/kg/hr

Methylene Blue 1-2 mg/kg IV over 5 minutes for methemoglobinemia……….Prilocaine

Question 4

Contraindications to NIV

Answer 4

• patient wishes
• patient compliance
• adequate respiratory effort
• vomiting
• pneumothorax
• bowel obstruction
• unable to fit mask due to anatomy or trauma
• decreased GCS

Question 5

Lung Protective Ventilation - ARDS

Answer 5

ALWAYS VT of 4-8 ML/KG

ARDS – high RR 20-26, HIGH PEEP 10-15, I:E 1:1

Question 6

Asthma Ventilation

Answer 6

ALWAYS VT of 4-8 ML/KG

ASTHMA – low RR 6-8, LOW PEEP 0-5, I:E 1:5

ensure plateau pressure < 30

expect high airway (peak) pressures

expect high pCO2 (prioritise oxygenation)

Question 7

Predictors of difficult airway

Answer 7

Short thyromental distance / anterior larynx

Small / recessed mandible

Mouth opening < 2cm

Poor neck ROM – e.g. RA, Ankylosing Spondylysis

Pregnancy

Obesity

History of difficult intubation

Mallamnpatti Score >3

Question 8

Triggers for laryngospasm

Answer 8

• intraoral injury or procedure
• stimulation of the posterior pharynx
• vomiting/aspiration
• ketamine
• anaphylaxis

Question 9

steps to manage laryngospasm

Answer 9

1. Apply O2 15lm BVM
2. Apply painful stimulus to angle of mandibe + jaw thrust
3. Attempt BVM ventilation – PPV with peep valve
4. Give deeper sedation – use propofol
5. Give sux IV 0.5mg/kg continue BVM
6. Give sux 1 mg/kg IV and intubate

Question 10

Biers Block drug + dose

Answer 10

Prilocaine 0.5%, 3mg/kg IV

duration = 20-30mins

toxic effects = seizure, decreased GCS, metHb

– quite safe cardiotoxicity profile – unlikely hypotension or arrythmia

Question 11

contraindications to Biers Block

Answer 11

Uncooperative patient – must be able to tolerate cuff

Allergy to prilocaine

Unable to gain 2x IV access

Sickle cell disease

Raynauds

Open fracture

Vascular complication from the fracture

HTN, SBP > 200

Question 12

Biers Block - complications

Answer 12

Seizure management

Abandon the procedure

Apply 15lmin O2 via NRBM, place on side, manage airway Midazolam 5mg IV alloquot – repeat q5mins

Check cuff still inflated – increase to max pressure

IV fluid 10ml/kg bolus

Monitor on cardiac monitor for arrythmias

Move the patient to resus if not there already

Check and correct hypoglycaemia

Intralipid not really for prilocaine – more bupivacaine

consider methaemoglobinaemia - administer methylene blue

Question 13

Sore Throat + Fever + airway obstruction, causes?

Answer 13

Epiglottitis

Anaphylaxis

Peritonsillar abscess

Ludwigs angina – less likely

Retropharyngeal abscess

angiooedema

Question 14

Adrenalin routes + doses for anaphylaxis

Answer 14

IM 10microg/kg of 1:1000 up to 500microg = 0.5ml

IV 1mcg/kg of 1:10000 bolus if peri-arrest, i

nfusion = 0.05 – 0.1 mcg/kg/min

Neb 5mg = 5ml of 1:1000

ET route 100mcg/kg in cardiac arrest

IO same as IV Cardiac arrest = 10mcg/kg IV every second round

Question 15

Indications for intubation in Trauma

Answer 15

• GCS < 9
• restless patient needing procedure e.g. CT scan
• combative patient
• elective hypocapnia required (“controlled” PCO2 – low-normal range)
• hypoxaemia

Question 16

ASA Class

Answer 16

• 1. Healthy patient, no medical problems
• 2. Mild systemic disease e.g. hypertension
• 3. Severe systemic disease, but not incapacitating
• 4. Severe systemic disease that is a constant threat to life
• 5. Moribund, expected to live less than 24 hours irrespective of operation
• E operation is an emergency

Question 17

Anaesthetic risk in pregnancy

Answer 17

• 10% incidence of spontaneous miscarriage if surgery performed in first trimester -6% overall
• significantly increased in later pregnancy
• difficult intubation -larger breasts -oedema may be present (especially in pre-eclampsia)
• higher risk of aspiration -abdominal distension -relaxation of the lower oesophageal sphincter
• higher gastric acidity
• higher rates of oxygen desaturation -higher baseline oxygen consumption -lower FRC and oxygen reserve capacity -impaired diagphramatic movement

Question 18

Complications of NIV

Answer 18

• facial skin necrosis -pressure sores
• conjunctivitis
• gastric dilatation
• aspiration
• pneumothorax

Question 19

RSI : HEAD INJURY

Answer 19

•fentanyl 0.5 – 1 µg/kg or lignocaine (lidocaine) 1 mg/kg IV

• may blunt the increase in ICP that occurs with instrumentation of the larynx
• usually given 1 - 2 minutes prior to other agents
• lignocaine (lidocaine) rarely used in Australasia for this purpose

•thiopentone 1.5 -3 mg/kg

• reduce dose or use fentanyl if hypotensive
• may also lower ICP

•rocuronium 1.2 - 1.5 mg/kg or suxamethonium 1 - 1.5 mg/kg (atropine handy in case of bradycardia)

• rocuronium does not cause an increase in ICP, however paralysis will be prolonged making subsequent neurological assessment difficult
• advantages of rapid paralysis outweigh the potential disadvantage of a brief increase in ICP with suxamethonium

DUNN

Question 20

RSI: HYPOTENSION / SHOCK

Answer 20

Induction agent

•induction with ketamine 1.5-2 mg/kg, or fentanyl 3µg/kg may prevent further deterioration in cardiovascular status

•etomidate 0.2-0.3 mg/kg is another alternative, if available

•thiopentone

• best avoided if possible
• or reduce dose to 1.5 mg/kg or less

•propofol

• intermediate risk of worsening hypotension
• reduce dose to 1 mg/kg, if possible

DUNN

Question 21

RSI: C-SPINE INJURY

Answer 21

Cervical spine injury

Indications for intubation

• concurrent head injury
• respiratory failure
• cord injury > C6 (phrenic nerve)
• 40% of patients with lesions at C3 will require longer term mechanical ventilation
• 15% of patients with lesions at C4 or C5 need longer term ventilatory support
• associated chest injury
• aspiration

Options

• get skilled assistance if assessed as potential difficult intubation
• orotracheal intubation with manual in line stabilisation (as described above)
• the method of choice – high success rate
• safe if performed properly
• causes more movement in the upper Cx spine than the lower spine

•video assisted intubation

• use whenever possible
• associated with less neck movement than traditional orotracheal intubation

•use an ETT over a bougie technique

• may result in less Cx spine movement
• only the posterior cords need to be visualised to pass the bougie, whereas most of the cords need to be seen to pass the ETT under vision
• fibreoptic assisted nasal intubation
• cricothyroidotomy
• not required routinely
• does not cause significant movement in the unstable spine
• movement greater at lower spine than upper
• tracheostomy
• retrograde intubation
• blind nasal intubation

-contra-indicated as very difficult to perform without head movement

Question 22

RSI: Maxillofacial trauma

Answer 22

Maxillofacial trauma

• may be uncooperative
• may obstruct when sedated or following analgesia
• hypoxic
• bleeding

Techniques

• get skilled help!
• fibre-optic intubation may be safest (oral route after topical LA)
• consider option of intubation in theatre with surgeon nearby
• RSI
• adequate suction vital
• good laryngoscopes x 3

-may fail if covered with blood

•prepare for a surgical airway

Deformed facial anatomy

• large mask size
• assistant to compress cheek or seal defect if open wound
• laryngeal mask
• rapid sequence induction
• surgical airway if not successful

Facial burns

• intubate early as severe oedema may develop
• nasotracheal intubation - using fibreoptic laryngoscope is the method of choice if airway compromise already present

Question 23

Lateral canthotomy

Answer 23

Lateral canthotomy

• surgical procedure used to compress the orbit
• if intraocular pressure > retinal artery pressure for more than 2 hours, the retina will start to be permanently damaged
• rarely required
• most common situations are post-traumatic
• other situations
• infection
• tumour
• spontaneous haemorrhage

INDICATIONS:

-increased intraorbital pressure causing compromise of the retinal blood supply

-visual loss

-afferent pupillary defect

-proptosis

-hard globe on palpation (IOP > 40 mmHg)

•anatomy

• medial and lateral canthal ligaments prevent globe from extrusion from the orbit
• originate medially and laterally from bony wall
• Y shaped and divide on the surface of the globe into inferior and superior ligaments

•procedure

• local anaesthetic infiltration of lateral canthus
• incise skin over lateral canthus towards bony orbit
• retract lower lid
• divide inferior lateral canthal ligament
• divide superior lateral canthal ligament if pressure does not drop sufficiently

Question 24

DROWNING - Pathophysiology

Answer 24

Phases

• voluntary breath holding
• involuntary laryngospasm secondary to liquid in oropharynx / larynx
• hypoxia, hypercarbia, acidosis
• may swallow large amounts water
• active respiratory movements but no gas exchange because of laryngospasm
• worsening hypoxia results in laryngospasm abating
• subsequent active breathing of liquid (volume very variable)
• changes in lungs, body fluids, acid-base and electrolyte balance
• washout of surfactant, pulmonary hypertension and shunting contribute to hypoxia
• additional changes if immersion is in cold water
• tissue hypoxia leads to multi-organ dysfunction and death

Pathophysiology

• abnormal gas exchange induced by pulmonary injury
• results in
• severe hypoxia
• cerebral oedema

•previously estimated that 10% of human drowning victims die without aspirating liquid

-this has now been challenged as water was found in 99% of cases in a large study of drowned victims

•absence of water aspiration at autopsy probably means the death was not due to drowning

-water does not passively seep into lungs after death

•aspiration of other material may occur

• vomit
• sand
• mud
• algae

•arterial oxygenation is profoundly affected when as little as 1 to 2.2 mL/kg of water are aspirated

-aspiration of water results in persistent hypoxia even if ventilation and circulation is restored

•the end result of drowning in both fresh or sea water is

• pulmonary oedema
• decreased pulmonary compliance
• increased V/Q mismatch
• most drowning victims do not aspirate enough fluid to cause life-threatening changes in blood volume
• life-threatening changes in serum electrolyte concentrations seldom seen, regardless of the type of water

-except in the Dead Sea!

• significant changes in Hb / Ht and renal function are rarely seen
• most drowning victims suffer a period of unconsciousness due to cerebral hypoxia
• patients who are awake and oriented on arrival in ED survive neurologically intact if management of pulmonary complications are successful
• patients who present in coma have a worse prognosis
• effectiveness of cerebral resuscitation measures need further evaluation in drowning

Question 25

DROWNING Prognosis

Answer 25

Prognosis

• no clinical score 100% accurately predicts which patients will survive the drowning event
• submersion time correlates with survival in some studies
• may be difficult to determine accurately
• 85% of survivors with good neurological recovery are submerged < 6 minutes
• 7.5% for 6–10 minutes
• 5% for 11–59 minutes
• <1% greater than 60 minutes
• > 10 minutes is considered a possible cut-off point for non-survival
• efficiency of initial resuscitation influences outcome
• water temperature no longer believed to influence outcome
• non-reactive pupils and a GCS of 5 on arrival in ICU are the best independent predictors of a poor neurological outcome
• 75% of survivors have good neurological outcome

Orlowski scale

• age < 3 years
• estimated submersion > 5 minutes
• no attempted resuscitation in the first 10 minutes after rescue
• coma on arrival at the ED
• metabolic acidosis on arrival with pH < 7.10
• outcome
• 90% chance of good recovery if < 3 of the above present
• 5% recovery if > 3 present

Glasgow coma scale

• patients with decorticate / decerebrate / flaccid response at 2 - 6 hours after rescue rarely survive or survive only with significant neurological impairment
• GCS of 5 = 80% risk of death / severe deficit
• patients with neurological improvement within 2 - 6 hours following rescue often recover with little or no neurological deficit
• 34% of comatose patients on arrival in ED die after presentation
• children comatose on arrival in ED
• 45% survive with normal brain function
• 15% survive with incapacitating brain damage
• 40% die
• patients with neurological improvement within 2 - 6 hours following rescue often recover with little or no neurological deficit
• time of first spontaneous respiratory effort
• if < 15 - 30 minutes after rescue, < 10% have significant neurological deficit
• if 60 - 120 minutes after rescue, 50 - 80% chance of sustaining serious neurological damage

Other prognostic factors

• on arrival in ED
• good prognosis

-spontaneous respiration and heart beat

•poor prognosis

• resuscitation duration > 25 minutes
• VT or VF on initial ECG
• fixed dilated pupils
• cardio or respiratory arrest

Prognosis in drowning and hypothermia

• patients with a core temperature > 33o C who have not ingested alcohol or other drugs and who do not make any respiratory effort < 40 minutes of rescue are unlikely to survive without significant brain damage
• in a study of 98 children with open water immersion and body temperature of < 34C, no child survived with good neurological outcome after > 25 min. of CPR
• chance of survival is related to rapidity of onset of hypothermia

-the more rapidly cooled = better chance of resuscitation

•water temperature rarely cold enough in Australia to provide protective effect from immersion

When CPR is likely to be futile

• water temperature > 6C and immersion time > 30 min
• water temperature < 6C and immersion time > 90 min
• submersion > 10 min without hypothermia (nearly all cases in Australia)
• persistent apnoea and asystole after 1 hour of post-rescue CPR provided not hypothermic
• serum K+ > 11 mmol/L
• blood is frozen

Question 26

DROWNING - Assessment

Answer 26

HISTORY:

Precipitating event

• syncope
• seizure
• drugs / alcohol
• hyperventilation
• trauma

Type of immersion

• the type and temperature of the water
• the amount and type of water contamination
• time of submersion and removal, if known
• conscious state on removal from water

Prehospital care

• bystander resuscitation / details (who administered and method of CPR)
• time of EMS arrival and commencement of resuscitation
• vital signs and conscious state on arrival of EMS
• breathing spontaneously
• palpable pulse
• GCS
• vomiting during rescue or resuscitation (very common)
• transportation time

Past history

• epilepsy
• alcohol abuse
• drug ingestion

NAI

•consider non-accidental injury or neglect in children

Question 27

DROWNING - MANAGEMENT

Answer 27

Management

•follow standard ACLS protocols

• chest compressions are ineffective in the water - immediately transfer to land or a boat
• attempt ventilation if unale to get patient out of the water
• consider additional initial ventilations as the injured lung may be harder to ventilate

Spinal immobilisation

•routine cervical spine immobilisation is not necessary

-potentially hazardous as vomiting common after drowning, particularly when CPR / ventilation provided

•immobilise if circumstances indicate trauma is likely

• history of diving
• use of a water slide
• motor vehicle crash
• signs of injury
• alcohol intoxication

•spinal injury in drowning is associated with clinical features of serious injury

Respiratory support

• focus of initial hospital care
• high risk of ARDS up to 72 hours following drowning
• alert, cooperative patients do not routinely require tracheal intubation
• intubate if pulmonary pathology does not respond to supplemental oxygen and CPAP
• if intubation required, support with controlled mechanical ventilation and PEEP
• use pressure-support ventilation starting at 10 cm H2O
• titrate CPAP or PEEP to maintain SpO2 ≥ 95%, using the lowest possible FiO2

Other pulmonary therapy

• antibiotics indicated if features of infection develop, guided by culture results
• consider antibiotics in paediatric pool drowning (due to aspiration of Pneumococcus in patient’s pharynx)

-although the evidence for efficacy is weak

• use broad spectrum antibiotics prior to culture results if submersion was in grossly contaminated water (e.g. sewerage)
• treat bronchospasm
• glucocorticoids ineffective for pulmonary complications in drowning

Circulatory support

•initial intravenous fluid therapy should be normal saline

-avoid hypotonic solutions

•hypovolaemia may be present following prolonged immersion, due to the hydrostatic pressure of the water on the body

-correct hypovolaemia but avoid excessive volumes due to the risk of pulmonary oedema

• monitor serum electrolytes
• invasive monitoring if concerned about intravascular volume

-prolonged inotropic support rarely needed

•consider ECMO if available

Cerebral resuscitation

• little research in this area
• restoration of spontaneous circulation a priority
• intracranial pressure management
• controversial area
• raised ICP may reflect hypoxic injury and treatment may not alter outcome
• consider ICP monitor if persistent coma despite correction of reversible causes
• target pCO2 25-30 mmHg if ICP raised

•induced hypothermia

• no convincing evidence for efficacy in drowning
• in the comatose patient with spontaneous circulation maintenance of T < 36C (as for post cardiac arrest) is reasonable

•other

• avoid hypoxia
• treat seizures
• prevent hyperthermia at all times
• maintain normoglycaemia
• insufficient evidence for other specific neuroresuscitative measures

Hypothermia

•manage according to standard protocols