10. Critical Care Flashcards

(120 cards)

1
Q

Why is it important to consider pain in the post op patient that you suspect is shocky?

A

Because pain can cause tachycardia and dyspnoea

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1
Q

Why should BP not be relied upon to predict if a P is seriously unwell?

A

Because it can be compensated and appear normal until later stages of decompensated shock

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2
Q

What type of problem affects the kidneys? Respiratory or circulatory?

A

Circulatory

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3
Q

If the pH is abnormal - what should you look at?

A

pCO2

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4
Q

When does a pCO2 indicate
(a) respiratory acidosis
(b) respiratory alkalosis?

What is the normal range for pCO2?

A

(a). >6.0 kPa
(b) <4.7 kPa

Normal range = 4.7 - 6.0

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5
Q

How can you check if the acidosis or alkalosis is respiratory or metabolic?

A

Check the bicarbonate levels

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6
Q

What is the normal range for serum bicarb?

What levels indicate
(a) metabolic acidosis
(b) metabolic alkalosis

A

Normal range -

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7
Q

How is metabolic acidosis / alkalosis compensated?

A

Rapidly compensated by inc / dec breathing - to inc/dec CO2 levels

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8
Q

How is respiratory acidosis / alkalosis compensated?

A

Slowly - via renal changes effecting loss or retention of bicarb

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9
Q

What can cause respiratory alkalosis?

A

Anything that increases RR or tidal vol

  • pain
  • PE
  • sepsis
  • pneumonia
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10
Q

What can cause respiratory acidosis?

A

Anything that decreases RR or tidal volume

  • Respiratory failure = severe pneumonia, sedation, opioids, COPD
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11
Q

How does increased CO2 levels affect a P?

A

Causes obtundation and sedation

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12
Q

What can cause metabolic acidosis?

A

Hypoperfusion
Failure of kidney to secrete acid
Inc bicarb loss from the kidney or gut

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13
Q

What can cause metabolic alkalosis?

A

Loss of acid (e.g. vomiting)

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14
Q

What is abdominal splinting?

A

Pain in the abdomen which restricts breathing as a result

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15
Q

What is atelectasis?

A

Partial collapse of a lung

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16
Q

Why do we use humidified O2 when oxygenating Ps?

A

To prevent the drying out of the respiratory epithelium

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17
Q

What levels of O2 are acceptable in a P? (Sats and PaO2)

A

Sats of 94% +
PaO2 of 8-9 kPa

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18
Q

At what level of PaCO2 may induced unconsciousness occur?

A

8 kPa +

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19
Q

What is the normal levels of O2 sat and PaO2 in a person?

A

98% saturation - about 12kPa PaO2

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20
Q

What is the minimum amount of O2 sats and PaO2 before the dissociation curve of O2 to Hb drops very steeply?

A

Around 90% saturation at 8 kPa

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21
Q

If O2 in the room is 21% and atmospheric pressure is 100kPa, why isn’t normal PaO2 20 kPa?

A

Because O2 in the alveolus is diluted with CO2 and water vapour

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22
Q

How much less should the PaO2 be than the inspired O2 concentration?

A

About 10 less (5 kPa CO2 and 4.5 kPa H20)

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23
Q

If a P is on inspired O2 at 30% - what should their arterial PaO2 be?

A

20 kPa

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24
If a P is on inspired O2 at 50% - what should their arterial PaO2 be?
40 kPa
25
What do you always need to know in order to interpret pO2 in ABGs?
The inspired O2 level
26
If a P is on 50% O2 and has an ABG of PaO2 15 kPa - what does this tell you?
That there is a severe problem with oxygenation
26
What can cause oxygenation deficits in surgical Ps?
V-Q abnormalities
27
Name 2 types of VQ abnormality. Which has a good response to oxygenating the P?
Shunt (lung is perfused but not ventilated) - poor response to oxygenation (Q>V) Dead space (lung is ventilated but not perfused) - good response to oxygenation. (V>Q)
28
What things can cause a VQ shunt?
Atelectasis Pneumonia Aspiration
29
What things can cause a VQ dead space?
PE Gas embolism Hypovolaemia
30
What is the difference between CPAP and PEEP?
CPAP is done to Ps that can breathe unaided. PEEP = done to ventilated Ps (Positive End Expiratory Pressure)
31
Invasive ventilation requires sedation and analgesia to tolerate the tube with the gag reflex. How can this be circumvented in seriously ill Ps?
Tracheostomy
32
How can you work out minute volume? What is minute volume?
Minute vol = Tidal vol x RR Minute vol = the amount of gas that a P is ventilated with in a minute
33
What are possible complications of invasive ventilation?
Barotrauma or volutrauma --> pneumothorax
34
What risk do you run if you get the wrong - Peak pressure - Tidal volume when ventilating a P?
Wrong peak pressure = risk of barotrauma Wrong tidal volume = risk of volutrauma
35
When do you need to consider ventilating a P?
If airway is threatened oxygenation failure ventilation failure severe cardiovascular failure
36
What is the risk of epidural if a P is on blood thinners?
Can get bleeding into the spinal canal
37
What is Virchow's Triad? What is it used for?
3 factors thought to contribute to thrombosis - used for DVTs. - Immobility - Vascular Injury - Hypercoagulability
38
What is a PE? What does it cause?
PE = blockage to branches of the pulmonary artery. Causes an acute increased in dead space
39
What are the S&S of PE?
Tachycardia (mot common) Dyspnoea Chest pain Haemoptysis Cough Fever Hypoxaemia
40
How do we investigate a PE?
D-Dimer Echo CTPA VQ Scan
41
What can we do to treat a PE?
Therapeutic anticoagulant (unfractionated heparin) Thrombolysis (alteplase) Embolectomy
42
What is a venocaval filter?
Is a filter placed into the IVC via the femoral vein by IR - is used to prevent clots reaching the lungs if PE is recurrent
43
What complications can arise from a PE?
Acute bleeding from Tx Pulmonary infarction (scarring from the damage) Cardiac arrest - right heart outflow obstruction Chronic pulmonary HT (due to increased back pressure on the heart) Thrombocytopenia (from heparin) Recurrent VTE
44
What bacteria tend to cause HAP?
Gram negative rods Staphylococcus
45
How can you differentiate pulmonary oedema from HF on CXR?
Pulmonary oedema (from HF) = more symmetrical infiltrates on CXR Pneumonia - can be defined more asymmetrical / defined.
46
What things can cause circulatory problems?
Sepsis Haemorrhage Shock
47
What is sepsis?
Life threatening organ dysfunction caused by dysregulated host response to infection.
48
Which factors are RF for sepsis?
Older than 65, even higher risk >75 Immunocompromised Indwelling lines Breaches of skin integrity / recent surgery Diabetes IV drug abuse Alcohol abuse
49
What are the clinical signs of sepsis?
Tachypnoea Tachycardia Urine output Skin colour, mottling, capillary refill Temperature - can be high, normal or low - hypothermia is a worse prognosis Hypotension - may not occur until later stages as BP usually maintained until P is at a collapsed shock level N&V&D are other possible signs of sepsis
50
What should you do if a P has a NEWS score of (a) 5 or (b) 7
5 - call someone senior to review within the hour 7 - find someone to review urgently Start SEPSIS 6 protocol
51
What are the differentials for sepsis? (Tachycardia, hypotension, confusion, oliguria)
MI (Do ECG, troponin & echo) Pancreatitis (serum amylase, MRCP) Massive PE Blood transfusion reaction
52
Name 3 types of acute haemorrhage
Primary (intraoperative) Reactive (within 24 hours) Secondary (7-10 hours post op)
53
How do we manage haemorrhage?
Direct pressure if possible Urgent review IV fluids, blood transfusion Tranexamic acid Clotting factors and platelets Surgery as needed
54
Which is the most physiologically similar fluid to give?
Hartmann's
55
What's the equation for calculating cardiac output?
HR x Stroke volume
56
What is stroke volume affected by?
Preload Contractility (force of heart contraction) Afterload (vascular resistance)
57
Why does preload affect stroke volume?
The larger the preload - the greater the stretch of the myocardium - therefore the greater the contraction force as a result and more fluid is output.
58
How much does fast AF reduce cardiac output by?
30% - the ventricles don't have sufficient time to fill before ejection takes place
59
What is mean arterial pressure?
The perfusion pressure to the organs.
60
How is mean arterial pressure calculated?
By the diastolic pressure plus 1/3 pulse pressure Pulse pressure = pressure difference between systolic and diastolic
61
What types of shock are there?
Hypovolaemic Septic Cardiogenic Spinal shock (causing SS block) Obstructive (cardiac tamponade or tension pneumothorax)
62
How much blood is usually lost before you can see alterations to the blood pressure?
About 30%
63
What are the signs of hypovolaemic shock?
Tachycardia, cold peripheries, anxiety or confusion, oliguria, inc RR
64
What are the signs of septic shock?
Bounding fast pulse, low BP, warm peripheries (but can get cold peripheries in cold septic shock), oliguria, inc RR
65
What are the signs of cariogenic shock?
High CVP Pulmonary oedema Low BP Cold peripheries Oliguria Inc RR
66
What happens in the early stages of shock?
HR increases BP is compensated by - adrenaline - raises diastolic pressure via vasoconstriction Skin - reduced blood flow as blood redirected to vital organs
67
In terms of vasodilation - what is the difference between hypovolaemic, cariogenic and septic shock?
Hypovolaemic & cariogenic = vasoconstriction occurs Septic shock = vasodilation occurs
68
How do we treat shock initially?
Does heart have adequate filling? If not - it will not respond to ionotropes. Fluids (Hartmann's) and leg raise If septic shock - vasodilation is the problem - so use vasoconstrictor (α adrenergic agonist) - NOR, metaraminol, ephedrine, phenylephrine Can also give inotrope - to increase contractility
69
Name an ionotrope
Dobutamine Adrenaline
70
Name a vasoconstrictor used for sceptic shock.
Noradrenaline Metaraminol Ephedrine Phenylephrine
71
What are the signs of an AKI?
Rise in creatinine +/- fall in urine OP
72
What are the pre-renal causes of AKI?
Sepsis Hypovolaemia Hypotension
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What are the intrinsic causes of AKI?
Nephrotoxins Contrast Vasculitis Nephritis
74
Which drugs are considered nephrotoxic?
Aminoglycosides ACEIs AT II receptor antagnoists NSAIDs
75
What is the post-renal cause of an AKI?
Outflow obstruction - e.g. stones, malignancy, blocked catheter
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How can you differentiate a post-renal cause of AKI from other causes of AKI?
Post-renal cause - get absolute oliguria
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How do you manage AKI?
Treat the underlying cause - stop any toxins Fluids and circulation support Imaging Don't give diuretics - may cause harm
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What complications can arise from AKI?
Pulmonary oedema Peripheral oedema Hyperkalaemia Uraemia
79
If the kidneys are impaired - what Tx can you give?
Haemofiltration - dialysis or CVVHD (continuous vent-venous haemo-diafiltration)
80
What is the difference between CVVHD and dialysis?
Dialysis is designed for long term use - is a much quicker process. CVVHD is for patients who are continuously on filtration for days / weeks at a time - much longer process.
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What are the indications to give a P CVVHDF?
Hyperkalemia Hypervolaemia Critically high creatinine / urea Severe acidosis Toxins
82
What treatments can be used to manage hyperkalaemia?
Calcium salts Dextrose/insulin Salbutamol All move K+ back into the cells
83
What is an acute, fluctuating change in mental status, with inattention, disorganised thinking and altered levels of consciousness?
Delirium
84
What are the 4 features of delirium?
Disturbance of attention (awareness of the environment) Change in cognition (memory deficit or disorientated) Acute change over hours or days Caused by physiologic consequences of a medical condition, substance intoxication or substance withdrawal
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What are the subtypes of delirium?
Hyperactive Hypoactive Mixed
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What screening tools can be used for delirium?
CAM MMSE 4-AT
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How is delirium managed?
Effective communication and reorientation (talk to the P and help them understand) Identify and manage the underlying cause. If not working consider haloperidol - lowest dose for the shortest time!
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What are the side effects of haloperidol?
Extrapyramidal side effects Risk with Ps who have long QTc interval and arrythmias
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What is a temporary, functional failure of peristalsis termed?
Ileus
90
What are the signs of ileum?
N&V Constipation Not passing wind Distension Discomfort Possible quiet bowel sounds
91
How long does it take for ileus to resolve?
Usually resolves after 3-4 days
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What are the risk factors for causing ileum?
Abdominal surgery (laparoscopic surgery reduces incidence) Drugs - esp opioids Delayed resumption of feeding and mobilisation Acute illness (sepsis, MI, pneumonia)
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What are the differentials for ileum?
Acute obstruction (think colicky pain) Peritonitis Acute abdomen causes
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How can acute obstruction appear on imaging?
Dilated bowel with transition point
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How do we treat ileum?
NBM & IV fluids Reduce opioids if present If vomiting and significant distension - NGT Correct electrolytes TPN if 4 days +
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What are common complications from ileum?
Risk of nosocomial infection Poor wound healing (due to poor nutrition) Aspiration pneumonia (with NGT) Atelectasis of lung (due to immobility and pain) VTE Sepsis - esp if TPN used
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How much: - Water - Na - K do patients need a day for maintenance?
2L Water 80 mmols / day Na 60 mmols / day K
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Why is enteral feeding best for Ps if possible?
Protect intestinal villi which are poorly perfused in shock If villi are poorly perfused, they become an inadequate barrier to bacterial = increased translocation into the portal blood system -> systemic bacteraemia and sepsis.
99
What level of care is - normal ward - enhanced care - HDU - ICU
Ward = 0 Enhanced care = 1 HDU = 2 ICU = 3
100
Which scoring systems are used to determine whether Ps need ICU support?
P-POSSUM NELA
101
Why do Ps sometimes go to ICU before surgery?
To optimise organ function to improve fitness for surgery For surgical complications
102
Which Ps need to go to ICU?
Those at present or imminent risk of life threatening organ failure that cannot be managed on a ward Must be reversible pathology and the P must be able to be rehabilitated.
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What is a SNOD?
Senior Nurse specialising in Organ Donation
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Name 2 types of organ donation
DCD (Donation after Cardiac Death) DBD (Donation with Brain Death - heart is still beating)
105
Which cranial nerves are tested by the following? 1 - Pupil reactions to light 2 - Stimulation to the cornea 3 - Supraorbital pain 4 - Gag reflex 5 - Caloric testing (cold water in ears) 6 - Apnoea despite rise in PaCO2
1 - 2 & 3 2 - 5 & 7 3 - 5 & 7 4 - 9 & 12 5 - 3,4,6,8 6 - Brain stem reflex
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What is dead space in the lungs?
Area that is ventilated but not perfused
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What is a shunt in the lungs?
Area that is perfused but not ventilated
108
A 40 year old patient has had a bowel resection in the morning. On return from theatre after an hour on the ward you are informed that the blood pressure keeps dropping and resolves temporarily with a fluid bolus of 250 mls of Hartmans. On review of the patient, he is anxious but awake. Blood pressure is 110/ 85 after receiving a second bolus of fluid. The heart rate is 120, resp rate 28, sats 100% on 40% oxygen. Urine output via the catheter is 10mls over the last hour. He has cool peripheries and capillary refill around 3 seconds. He was stable when returned from theatre. After assessing him the blood pressure drops to 85/69 and heart rate increases to 125, like how it was prior to the fluid bolus. A blood gas is taken. pH 7.3, pCO2 3.2, pO2 39, Hb 90, Bicarbonate 19, BE -6, Glucose 7, Lactate 3 What one of the following is your first priority? (A). Do a 12 lead ECG (B). Discuss with senior about doing a CTPA (C). Order blood and start transfusion, call operating surgeon Correct answer (D). Start IV antibiotics after taking blood cultures (E). Administer furosemide and call ICU regarding haemofiltration
This patient must be assumed to have post-operative bleeding hence C is correct. Initial response to fluid challenge is followed by subsequent deterioration (transient responder to fluids) therefore it can be assumed that there is ongoing fluid loss which in this case is most likely to be blood. Hb is fairly normal as acute bleed with little dilution (remember that haemoglobin measurement is a concentration rather than an absolute value and with acute bleeding there is no drop as haemodilution takes some time to show as a fall in Hb concentration). Worst answer is giving furosemide as will actively worsen hypovolaemia. It is probably too soon for a septic complication (unless there has been inadvertent bowel injury or similar).
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68 year old patient 8 days following surgery for a fractured femur and rib fractures following being knocked off his bike develops acute shortness of breath and tachycardia. On examination he has equal breath sounds, central trachea but his blood pressure is reduced to 90/50. His pulse oximeter shows saturations of 88%. The most likely cause of his symptoms is? (A). An acute myocardial infarction (B). A pulmonary embolism Correct answer (C). A tension pneumothorax (D). An acute pneumonia (E). An unrecognised spinal injury
Most likely is a PE therefore B (acute SOB, low BP, typical timeframe after high risk injury, likely poor mobility). No evidence for other causes. Spinal injury unlikely but would typically show paralysis and bradycardia
110
A 72 year old patient is admitted with abdominal pain and a high amylase of 3100. He is prescribed analgesia and 3 litres of Hartmann’s solution over 24 hours. His blood pressure is 111/84, HR 102 and RR 20. His urine output has been low for which he received 40mg of furosemide by a colleague 3 hours ago. His urine output improved to 80 per hour but in the last hour has decreased again to 10ml an hour. Appropriate management would be the following 2 options: (A). Repeat furosemide or consider an infusion (B). Give a fluid bolus of 250ml of Hartmann’s solution Correct answer (C). Repeat the amylase test (D). Discuss with your senior doctor Correct answer (E). Refer to ICU asking for Haemofiltration
Fluid bolus is the most important first step as patients have high fluid losses with significant pancreatitis. Discuss with senior doctor as the patient needs further management, including possible ICU management hence B and D. Reason for low urine output is hypoperfusion of the kidneys so giving furosemide will temporarily increase the urine output but will actually worsen the shock in the longer term through additional fluid loss. Referral for haemofiltration is incorrect because he needs fluid and circulatory management. Repeat amylase has no role in the management of pancreatitis.
111
A patient receiving IV morphine boluses for severe abdominal pain has become less responsive. His Glasgow coma score is 8 with E2,V2 and M4 and he has very small pupils. His respiratory rate is 6, HR 75 and BP 124/83. Blood gases show: pH 7.2, pCO2 9.9, pO2 10, Lactate 1.5, BE 2 Which of the following is correct? (A). The pCO2 has caused unconsciousness (B). He should not be prescribed oxygen (C). He should be given a full dose of naloxone 400 micrograms by bolus (D). He should have a CT scan of his head immediately (E). Give repeated doses of diluted naloxone and reassess
The problem is likely opiate overdose. The unconsciousness is most likely due to respiratory depression and narcosis by CO2. He should be prescribed oxygen as pO2 is slightly low at 10 and likely to get worse, plus diluted naloxone boluses, hence the answer here is E. Full dose naloxone will cause severe pain as it will reverse the analgesic effects of the morphine as well as the CNS depression so this needs to be managed carefully. If naloxone does not work then CT head may be required after. Repeated doses may be needed as the half life of naloxone is shorter than the morphine.
112
A 78 year old patient who had a Trans Urethral Prostate Resection the previous day becomes confused and pulls out his drip overnight. The nurses have called you and are restraining him, but he is trying to pull out his catheter and get out of bed. Which of the following are true (select all that apply)? (A). A CT scan of his head should be arranged urgently (B). Blood should be taken to check sodium levels and glucose (C). Check if the catheter is blocked Correct answer Correct: Try to talk and reassure him Correct answer (E). Immediately give high dose haloperidol
He has acute hyperactive delirium. First look for causes such as hyponatraemia after TURP or glucose abnormality, blocked catheter could be cause, due to clots. Communication and de-escalation are the first priority and then low dose haloperidol if he is a danger to himself. Hence B, C and D are true. He would not manage a CT head in current agitated state and high dose haloperidol is inappropriate.
113
A 48 year old patient has nasogastric feeding as part of his management for colonic disease. He has been on the ward for 2 weeks and today has developed a pyrexia of 38.2 degrees, a tachycardia of 120, Respiratory rate of 32 and blood pressure of 131/75. His saturations have decreased to 91% while on air. On examination he has warm peripheries, trachea central, decreased air entry in his right lower zone and crackles. He is conscious but anxious. He tells you he pulled his NG tube out partially earlier but one of the staff pushed it back in. He is on Omeprazole regularly. What are the priorities (select all that apply)? (A) Immediately stop NG feeding Correct answer (B). Get an urgent chest XR Correct answer (C). Check the pH of gastric aspirate from the NG Tube (D). Take blood cultures Correct answer (E). Start IV fluids 2 litres a day
Story focusses on misplaced NGT into the lung causing a pneumonia. A is correct as is B and D. CXR with the tube in position proves the diagnosis and then it should be removed if in the lung. Blood cultures before use of antibiotic management to guide specificity. The pH will not be helpful as he is on an antacid. IV fluids are not a priority as there is currently no evidence of shock. This is a never event and a misplaced NGT should never be manipulated without check CXR prior to resuming feeding.
114
A 32 year old patient has had bowel resections and prolonged intermittent ileus. They have been started on TPN (total parenteral nutrition) via a central line in the right internal jugular over the last 3 weeks. Over today they have become slightly confused but able to talk, Resp rate 30, HR 120 and blood pressure 90/35. Previously their observations were in normal ranges. Urine output is 20ml per hour. The abdomen is soft and non-tender. Urinalysis is normal Bloods have been taken, which were difficult due to poor venous access, hence were taken from the central line as usual. Results include Hb 119, WCC 21, plts 200, Na 134, K 4.2, Urea 18, Creatinine 80, glucose 6.7 and CRP 120. The lactate is 4 and BE -8 on venous blood gases. A chest XR has been done which shows correct position of the CVP line and clear chest fields. Which of the following are the two most important actions (select all that apply)? Hide answer choices (A) Take blood cultures via the central line (B). Start oral antibiotics (C). Remove the central line Correct answer (D). Arrange Chest, Abdominal and Pelvic CT scan (E). Give a diuretic
This case is based on line sepsis. This CVP line is not dedicated to TPN as bloods are taken, has been in a long time (3 weeks) and TPN is a high risk for sepsis. Other common causes of sepsis excluded including chest, abdo, urine. Best answers are to remove the central line and do blood cultures from the line first, A and C. If cultures are positive from CVP line then confirms diagnosis and guides antibiotics. If there is only a possibility of infection such as isolated pyrexia then blood cultures from the line can be taken to confirm diagnosis. As this patient is in full septic shock then removal of line is mandated. CT scan is not indicated as a priority as further examination does not suggest other causes. Diuretic for poor urine output again is inappropriate. He needs IV antibiotics not oral. Poor venous access is not a reason to over-keep a central line if risk of sepsis.
115
Which of the following are true based on respiratory pathophysiology (select all that apply)? (A). A shunt (perfused lung that is not aerated) in terms of VQ abnormalities is the underlying pathophysiology of a PE (B). CPAP (Continuous positive airway pressure) improves oxygenation by recruiting alveoli Correct answer (C). A tracheostomy is used to aid weaning from ventilation by avoiding sedation Correct answer (D). Dead space is increased by atelectasis and lobar pneumonia (E). A blood gas must always include the oxygen content administered regarding pO2
B and C and E are correct. CPAP applies positive pressure to the airway which prevents the small airways from collapsing at the end of expiration. A tracheostomy reduces the work needed for ventilation by reducing dead space where there is air in the airway but not within the part of the lung where gas exchange occurs. It is also unpleasant for patients to be awake with an endotracheal tube in situ so it is easier to wean patients with a tracheostomy than an ET tube. A and D, are the opposite way round (a PE causes hyopoxia due to lack of blood flow to aerated sections of lung and atelectasis and pneumonia reduce dead space). pO2 on a blood gas cannot be interpreted without inspired oxygen level.
116
Regarding shock states where there is inadequate tissue perfusion which one is true? (A). Hypovolamic shock has a reduced afterload (B). Septic shock may coexist with hypovolaemic shock (C). Cardiogenic shock has a decreased preload (D). Septic shock has an increased cardiac output due to increased contractility (E). Hypovolaemic shock is treated by giving a vasoconstrictor infusion
B is correct in that several types of shock can coexist. A and C are incorrect, the opposites are true. In septic shock the increased cardiac output is due to tachycardia; patients actually have a reduced contractility. Vasoconstrictor for hypovolamic shock is wrong as the first step in management is with fluid boluses. Septic shock (and neurogenic) are caused by peripheral vasodilatation and are therefore managed with vasoconstrictors (along with additional fluids).
117
Regarding intensive care units, which of the following is true? (A). All patients should be admitted to ICU for organ support (B). The patient to nurse ratio in ICU is one nurse to 2 patients (C). If ICU treatment becomes futile then treatment can be withdrawn Correct answer (D). Organ donation is only considered if the patient is brain dead (E). Once ventilated, patients cannot be moved from the unit
C is the only correct answer. Only patients with reversible pathology should be admitted who will benefit, ICU nurse ratio is 1:1, 1 to 2 is for high dependency units (HDU). Organ donation can be considered for patients having planned withdrawal and expected to die quickly, with rapid transfer to theatre and a team ready to remove organs immediately after death. Patients who are ventilated are regularly moved to theatre, CT scanning and other hospitals with an appropriate skilled team and portable equipment.
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