Describe the etiology and pathogenesis of colorectal cancer

Book
Text readings

LeMone, P, Burke, K, Dwyer, T, Levett-Jones, L, Moxam, L, Reid-Searl, K, Berry, M, Hales, M, Luxford, Y, Knox, N & Raymond, D (eds) 2014, Medical-surgical nursing: critical thinking in client care, Pearson, Frenchs Forest, Australia.

Chapter 4 ‘Nursing care of clients having surgery’

Chapter 10 ‘Nursing care of clients experiencing altered fluid, electrolyte and acid-balance’

Chapter 29 ‘Nursing care of clients with kidney disorders’.

Kozier and Erb’s fundamentals of nursing, vol.3, 2nd edn, Pearson, Frenchs Forest, Australia

Chapter 54 ‘Fluid, electrolyte and acid-base balance’, pp. 1587-1649.

McDonough, D 2014, ‘Nursing care of clients experiencing altered fluid, electrolyte and acid-balance’, in Medical-surgical nursing: critical thinking in client care, LeMone, P, Burke, K, Dwyer, T, Levett-Jones, L, Moxam, L, Reid-Searl, K, Berry, M, Hales, M Luxford, Y, Knox, N & Raymond, D (eds), Pearson, Frenchs Forest, Australia.

Walker, S 2012, ‘Fluid, electrolyte and acid-base balance’, in Kozier and Erb’s fundamentals of nursing, vol. 3, 2nd edn, Pearson Australia, pp. 1587-1649.

Online activity
Access Australia’s Health (2008) to find out more about colorectal cancer, http://www.aihw.gov.au/cancer/bowel/
1. incidence
2. Mortality
3. Death rate
4. Survival rate
Explore the National Health and Medical Research Council website, http://www.nhmrc.gov.au/publications/synopses/cp106/cp106divided.htm#a3 and establish which population health-screening approaches are used for early detection of colorectal cancer in Australia.
Describe the aetiology and pathogenesis of colorectal cancer.
Scenario: Mr A Barrett
Mr A Barrett is a 74 year old man diagnosed with cancer of the colon. He sought medical treatment after noticing rectal bleeding and changes in bowel habits such as constipation and diarrhoea. He is anaemic and with a family history of bowel cancer and the GP performed a digit rectal examination. No palpable rectal mass was found and Mr Barrett was referred to gastroenterologist and colonoscopy. Subsequently Mr Barrett was diagnosed with left-sided colon cancer and a bowel resection was scheduled.
Pre-operative handover:
Admission observations
Temperature 36.7C
Pulse rate 90
Respiratory rate 18
Blood pressure 150/90

Co-morbidities
COPD (diagnosed 15 years ago)
Osteoarthritis (OTC non-steroidal anti-inflammatory drugs (NSAIDs) ibuprofen and paracetamol)
Type 2 diabetes (diet controlled)
Medical orders
Two PicoPreps the night before surgery and clear fluid diet
Nil orally from midnight
Prophylactic anticoagulant – enoxaparin sodium
Prophylactic antibiotics – metronidazole 500 mg IV; cephalothin 2g IV

1 Why is Mr Barrett considered to be ‘high risk’?
2 What other information would you need if you were caring for Mr Barrett pre-operatively?
3 What other assessments are needed at this stage?
4 Why are sodium phosphate bowel preparations such as Fleet Preps and PicoPreps used with extreme caution in older people?

Handover report
Mr Barrett’s surgery proceeds without major complications and the handover the following morning is as follows:
We have Mr A Barrett in room 22. He is 74 years old. He had a partial colectomy and formation of a colostomy for bowel cancer. He is under Dr Ng. His surgery was uneventful and he was stable throughout. He has a morphine PCA and an IV running at 84 mL per hour. He didn’t have a good night as his BP dropped and he needed two fluid challenges of 300 mL each. He is still dry – he has an IDC on hourly measures and they have dropped progressively overnight. His urine output has been about 25-30 mL per hour since midnight. He has a bellovac and it has drained 300 mL since yesterday. His wound has a dry dressing and it is intact. He has a drainage bag over the stoma—no drainage. His oxygen therapy is still at 6 litres a minute. He is tolerating the mask. His sats are ok. The obs are due again at 0800. He is on 4th hourly BGLs, type 2 diabetic—diet controlled, BGLs are ok. He lives alone as his wife passed away a year ago. His daughter should be in later today.
Collect cues / information
Gather new information
Mr Barrett’s current observations are:
Temperature 37C
Pulse rate 112 (weak and thready)
Respiratory rate 22
Blood pressure 90/50
Oxygen saturation level 97%
Hourly urine output (average) 26mL/hr
BGL 4mmol/L
What other clinical assessment information do you need to collect? From the list below, identify the five cues that you believe are most relevant to your assessment of Mr Barrett at this time.
a Appetite (nil)
b Condition of oral mucosa (dry and tongue furrowed)
c Oral intake (minimal)
d Pain 3 out of 10
e Cognitive state (restless and anxious)
f Colour (pale)
g Skin condition (poor skin turgor)
h Level of thirst (reports that he is very thirsty)

Process information
(a) Interpret
The next step of the clinical reasoning cycle is to interpret the data (cues) that you have collected by careful analysis and by applying your knowledge of fluid balance. By comparing normal versus abnormal you will come to a more complete understanding of Mr Barrett’s signs and symptoms.
1. Which of the following are considered to be within normal parameters for Mr Barrett?
(a) Temperature: 37°C
(b) Pulse rate: 112 beats per minute
(c) Respiratory rate: 22 breaths per minute
(d) Blood pressure: 90/50
In the handover report a number of statements were made that need further clarification. Analyse each of the following statements and physiological parameters. Compare normal versus abnormal, and identify what you would consider ‘normal’ for Mr Barrett at this time.

2. His sats (SaO2) are OK.’ A ‘normal’ oxygen saturation level for Mr Barrett would be:
(a) 80-85per cent
(b) 85-90per cent
(c) 90-95per cent
(d) 95-100per cent

3. ‘He has an IDC on hourly measures and these are still a bit low’. For Mr Barrett a ‘normal’ urine output would be at least:
(a) 41 mls per hour
(b) 82 mls per hour
(c) 60 mls per hour
(d) 10 mls per hour
4. ‘His BGLs are acceptable.’ A ‘normal’ BGL for Mr Barrett would be:
(a) 4-8 mmol/L
(b) 2-4 mmol/L
(c) 1-3 mmol/L
(d) 8-10 mmol/L

(b) Discriminate
From the cues and information you now have, you need to narrow down the information to what is most important. From the list below select four cues that you believe are most relevant to Mr Barrett’s fluid status at this time.
(a) Blood pressure
(b) Respiratory rate
(c) Temperature
(d) Pulse
(e) Condition of wound
(f) Oxygen saturation
(g) Condition of oral mucosa
Level of consciousness
(i) Appetite
(j) Urine output
(k) Pain
(l) Colour
(c) Relate
It is important to cluster the cues together and to indentify relationships between them (based on the information you have collected so far).
Label the following ‘true’ or ‘false’:
(a) Mr Barrett is hypertensive from excessive IV fluids and pain.
(b) Mr Barrett is probably hypoxic as a result of the extended anaesthetic period and his COPD.
(c) Mr Barrett could be hypotensive and tachycardic from the pre-operative bowel prep.
(d) Mr Barrett could be hypertensive as a result of surgical blood loss and pain.
(e) Mr Barrett could be tachycardic and hypotensive from a third-space fluid shift.
(f) Mr Barrett is febrile and tachycardic because of a post-operative wound infection.
(g) Mr Barrett could be oliguric from hypotension and the PCA.

(d) Infer
From what you know about Mr Barrett’s history, surgery, signs and symptoms (as well as your knowledge about fluid balance), identify which of the following inferences are correct: (Select the two that apply.) Outline your rationales:
(a) Mr Barrett is normotensive and bradycardic.
(b) Mr Barrett is hypertensive and tachycardic.
(c) Mr Barrett is febrile and normotensive.
(d) Mr Barrett is oliguric and tachycardic.
(e) Mr Barrett is hypertensive and afebrile.
(f) Mr Barrett is polyuric and hypotensive.
(g) Mr Barrett is hypotensive and afebrile.

(e) Predict
If you do not take the appropriate actions at this time, what could happen if Mr Barrett if his fluid imbalance is not corrected? (Select the four that apply.) Explain the rationales for what you have chosen:
(a) Mr Barrett could go into shock.
(b) Mr Barrett’s condition will gradually improve over the next few days.
(c) Mr Barrett could develop acute kidney injury.
(d) Mr Barrett could develop pulmonary oedema.
(e) Mr Barrett could die.
(f) Mr Barrett could become hypoxic.
Identify the problem / issue
1. Select from the following list the correct nursing diagnosis for Mr Barrett and explain your rationale (why – what is the reason, provide evidence).
(a) Hypervolaemia and dehydration
(b) Hypovolaemia and pulmonary oedema
(c) Dehydration and atelectasis
(d) Acute renal failure and pulmonary oedema
(e) Hypovolaemia and dehydration
2. Do you know the difference? Please outline the difference between hypovolaemia and dehydration.
3. Identify four factors (at least) that led to Mr Barrett’s deterioration?
4. Describe causes and consequences of third-space fluid shift.
Establish goals
Before implementing any actions to improve Mr Barrett’s condition, it is important to clearly specify what you want to happen and when. From the list below, choose the most important short-term goals for Mr Barrett’s management at this time. Provide rationales for your choices and provide evidence to support your rationale:
(a) For Mr Barrett to be normotensive with urine output at least 30-40 mL per hour within the next 24 hours
(b) For Mr Barrett to be normotensive with urine output greater than 80-100 mL per hour within the next 2 hours
(c) For Mr Barrett to be normotensive with urine output at least 40-45 mL per hour within the next 2-4 hours
(d) For Mr Barrett to be normotensive with urine output greater than 80-100 mL per hour within the next 24 hours
Take action
1. From the list below, choose the seven most immediate actions you should take at this stage. When you have outlined your choices, describe your rationales—why you chose as you did (provide evidence to support your rationale):
Note: all of these are actions are important but you need to select those actions that are most important to the management Mr Barrett’s deteriorating condition!
(a) Notify Mr Barrett’s doctor of his condition.
(b) Monitor Mr Barrett’s level of consciousness.
(c) Monitor Mr Barrett’s pain score.
(d) Reassure patient.
(e) Monitor the condition of Mr Barrett’s drain, stoma and wound.
(f) Check that the IV cannula is not kinked or blocked.
(g) Administer a fluid challenge and increase Mr Barrett’s IV fluid rate as ordered.
Check that the urinary catheter is not kinked or blocked.
(i) Monitor Mr Barrett’s vital signs and oxygen saturation level.
(j) Raise the foot of Mr Barrett’s bed.
(k) Strictly monitor Mr Barrett’s input and maintain hourly urine measures.
2. In the table below match the rationales for care to the corresponding nursing action.
Nursing action Rationale
Document all nursing observations and actions accurately and contemporaneously Anxiety and restlessness may indicate worsening fluid status
Daily weight (same scales, same clothes) To increase fluid intake
Check cognitive status regularly To maintain psychosocial wellbeing
Monitor haemodynamic status closely Sodium, potassium, urea and creatinine are important indicators of fluid status and renal function.
Regular position change To manage dry mouth and tongue and to promote patient comfort.
Maintain patent IV access and monitor IV site regularly. This is the best indication of fluid status.
Encourage oral fluids as ordered/tolerated by patient. To monitor changes in fluid status
Maintain oxygen therapy via nasal prongs or Hudson mask and hourly oxygen sats To ensure adequate oxygen delivery
Check UEC (urea, electrolytes and creatinine) as ordered To identify improvement or deterioration in Mr Barrett’s condition
Reassure patient To ensure clear, accurate and timely communication between all health professionals caring for Mr Barrett.
Provide regular oral care To prevent pressure areas due to dry skin.
Check specific gravity of urine To ensure fluids are administered as ordered

Evaluate
It is now 1100, two hours since Mr Barrett was given a 500mL fluid challenge and had his IV rate increased to 125mL/hr. Each of Mr Barrett’s signs and symptoms provide you with data to make a determination of whether or not these interventions have been effective and whether his condition is improving.
1. Rate each of the following signs and symptoms as either:
• unchanged
• improving
• deteriorating
Cognitive status: Patient restless and anxious
Level of thirst: Patient reports some thirst
Pulse: 90
Urine output: 36mL/hr
Oral mucosa: Mouth is dry and tongue furrowed
Oral intake: Tolerating sips of water
BP: 110/70
Colour: Pale
Skin condition: Skin turgor poor

2. You now need to synthesise these parameters to decide whether Mr Barrett’s fluid status has improved overall. Which of the following statements are most correct? Provide your rationale and evidence to support your choice:
(a) Mr Barrett’s fluid status has improved significantly.
(b) Mr Barrett’s fluid status has not improved and you need to contact the doctor again.
(c) Mr Barrett’s fluid status has improved significantly but still requires careful monitoring.
(d) Mr Barrett’s fluid status has improved slightly but still requires careful monitoring. You will need to contact the doctor again if further improvement is not seen in the next four hours.
(e) Mr Barrett’s fluid status has not improved but you will monitor his condition carefully for the next four hours.
Reflect
1. Could Mr Barrett’s deterioration have been prevented? If so, how?
2. What are three of the most important things that you have learned from this scenario?
3. What actions will you take in clinical practice as a result of your learning from this scenario?
Mr Barrett’s hospital stay continues. A new day means another day of clinical reasoning to assess, care, anticipate complications and evaluate Mr Barrett’s condition.
Collect cues / information
Gather new information
When you enter Mr Barrett’s room at 1500 hrs to take his observations you note that he has a dry irritating cough, is talking to himself, plucking at the bed sheets and attempting to get out of bed. When you say ‘Are you alright Mr Barrett?’ he does not reply or look at you but mumbles the words, ‘My head’s hurting’. Then he vomits a small amount of clear fluid. The nurse caring for the patient in the next bed, shakes her head, saying ‘just what we need today, another one with dementia’.

1. This nurse’s comment is an example of (select two correct answers):
(a) Ascertainment bias
(b) Diagnostic momentum
(c) Pattern matching
(d) Ageism
(e) Intuition
2. From the following list select the seven assessments that are most appropriate at this stage.
a Glasgow coma scale:
b Pupillary response:

c Pain score:
d Mental health assessment:
e BGL:
f Temperature:
g Level of consciousness:
h Mini-mental assessment:
i Oxygen saturation level:
j Condition of wound:
k Stoma observations:
l Respiratory rate:
m IV rate:
n Urine specific gravity: 14
PEARL (Pupils E
Equal and Reactive to Light)
6
N/A
7.0mmol/L
37.2C
Responsive but slightly confused
N/A
90%
dressing dry and intact, no ooze, or redness around the area
pink, moist, clear mucous discharge
31
125 mL/hr
1004

Process information
(a) Interpret
1. Based on Mr Barrett’s signs and symptoms, do you think he is in a positive or a negative balance?

2. Mr Barrett’s serum electrolytes are:
sodium (Na+) 128 mmol/L
potassium (K) 3.3 mmol/L.
Describe what are the normal levels of serum sodium and provide evidence?
(a) 115-125 mmol/L
(b) 135-145 mmol/L
(c) 165-185 mmol/L
(d) 130-150 mmol/L
3. Outline what are the normal levels of serum potassium supported by literature?
(a) 2.8-3.9 mmol/L
(b) 4.8-5.9 mmol/L
(c) 3.8-4.9 mmol/L
(d) 3.0-4.0 mmol/L

4. Hyponatraemia can cause which of the following? (Select the five correct answers.)
(a) Constipation
(b) Confusion
(c) Headaches
(d) Polyuria
(e) Nausea and vomiting
(f) Abdominal cramps
(g) Thirst
Muscle weakness
(i) Low grade fever
(j) Flushed skin

5. Which of the signs and symptoms of hyponatraemia is Mr Barrett exhibiting? (Select the three correct answers.)
(a) Confusion
(b) Abdominal cramps
(c) Headache
(d) Nausea and vomiting
(e) Muscle weakness
6. Hypokalaemia can cause which of the following? (Select the seven correct answers.)
(a) Nausea
(b) Irregular pulse
(c) Arrhythmias
(d) Diarrhoea
(e) Cardiac arrest
(f) Decreased bowel sounds
(g) Irritability
Cramps
(i) Hypotension
(j) Polyuria
(k) Muscle weakness

7. Which of the signs and symptoms hypokalaemia is Mr Barrett exhibiting? (Select the one correct answer.)
(a) Arrhythmias
(b) Cardiac arrest
(c) Irregular pulse
(d) Decreased bowel sounds
(e) Cramps
(f) Polyuria
(g) Muscle weakness

(b) Discriminate, (c) Relate, and (d) Infer
From the list below, identify the four clinical indicators that may be an early warning of a potential adverse outcome for Mr Barrett. Ensure you support your selection with evidence:
(a) Chest pain
(b) Urine output 400mL over 8 hours
(d) Respiratory rate 5 – 9 or 31 – 40 breaths per minute
(e) Newly reported pain or uncontrolled pain
(f) Systolic Blood pressure 80 – 100mmHg or 181- 240mmHg
(g) Pulse rate 40 – 49 or 121 – 140 beats per minute
Greater than expected fluid loss from drains
(i) SpO2 90 – 95 per cent
(j) Blood glucose level 1 – 2.9 mmol/L

(e) Predict
If you do not take the appropriate actions at this time, what could happen to Mr Barrett if his fluid imbalance is not corrected? (Select the four that apply.)
(a) Mr Barrett could die.
(b) Mr Barrett could go into shock.
(c) Mr Barrett could become hypoxic.
(d) Mr Barrett’s condition will gradually improve over the next few days.
(e) Mr Barrett could develop pulmonary oedema.
(f) Mr Barrett could develop acute kidney injury.

(f) Match
Have you ever seen someone with the same signs and symptoms as Mr Barrett? If so, what was done to manage the situation? If you have not experienced this situation before, look to the literature and provide rationale and evidence for how to manage.
Identifying the problem / issue
Re-examine the information you have about Mr Barrett:
BP 150/90
Pulse 102 (full, bounding and irregular)
Respiratory rate 31
Oxygen sats 90%
Urine output 15-30mls per hour
BGL 6.9 mmol/L.
Na 128 mmol/L
K 3.3 mmol/L
IVT 125ml/hr
Cough dry and irritating

1. From this information identify the three correct nursing diagnoses for Mr Barrett. Support your rationales with evidence-based literature:
(a) Hypovolaemia
(b) Hypervolaemia
(c) Dehydration
(d) Dementia
(e) Delirium
(f) Electrolyte imbalance

2 . Identify the cue cluster below that supports your nursing diagnosis of hypervolaemia:
(a) Hypertension
Hyperglycaemia
Tachypnoea
Hypoxia

(b) Hypertension
Tachycardia
Febrile
Hypoxia

(d) Altered cognition
Tachycardia
Tachypnoea
Hypoxia

3. List three factors that may have contributed to Mr Barrett’s hypervolaemia.
1-
2-
3-

4. Mr Barrett’s tachypnoea and cough is most likely due to which of the following? Outline the connection between the tachypnoea and ……………………:
(a) A mild upper respiratory tract infection
(b) Early stages of pneumonia
(c) Early stages of pulmonary oedema
(d) Intubation during the anaesthetic
(e) History of smoking
Establish goals
From the list below, choose the four most important goals for Mr Barrett’s management at this time.
(a) Patient to be self-caring and ambulant
(b) Vital signs within normal parameters
(c) Oral food and fluid intake established
(d) Bowels sounds normal
(e) Oxygen saturation level > 94 per cent
(f) Improved cognitive status
(g) Stoma functioning
Urine output satisfactory
Take action

1. From the list below choose the five most immediate actions you should take at this stage.
(a) Contact attending doctor immediately to request medical review.
(b) Administer a diuretic.
(c) Continue to monitor haemodynamic status closely.
(d) Administer oxygen 6-8 litres per minute.
(e) Complete and document vital signs QID.
(f) Sit Mr Barrett in a semi-fowlers position.
(g) Check weight each day.
Decrease IV rate TKVO pending medical orders.
(i) Monitor cognitive status.
(j) Maintain patent IV access and monitor IV site regularly.
(k) Monitor for improvement in serum electrolytes.
(l) Regular position change to prevent pressure areas.
(m) ECG.
Lay patient down and raise his leg above the level of this heart.
(o) Administer oxygen 2 litres per minute via nasal prongs.

2. Using ISBAR (Identity, Situation, Background, Assessment, Request/Recommendation), document how you would communicate with Mr Barrett’s doctor or the Rapid Response Team.
I Identify

S Situation

B Background

A Assessment

R Request/recommendation

3. From the list below choose the three nursing actions that you anticipate taking after the clinical review.
(a) Increase IV rate following doctor’s orders.
(b) Administer a diuretic (probably frusemide IV) following doctor’s orders.
(c) Give anginine tablets following doctor’s orders.
(d) Titrate IV to rate ordered by medical officer.
(e) Administer insulin following doctor’s orders.
(f) Take blood for serum creatinine and urea levels.
(g) Prepare to give a fluid challenge.
Evaluate
List eight signs and symptoms that will indicate to you that Mr Barrett’s condition has improved following clinical review and initiation of appropriate actions.

1-
2-
3-
4-
5-
6-
7-
8-
Reflect
Respond to the following questions with reference to Mr Barrett.
1 How could Mr Barrett’s deterioration have been prevented?
2 What have you learnt from the scenario that you can apply to your future practice?
3 Why are older post-operative people at risk of fluid and electrolyte imbalance?
4 What actions should nurses take to promote kidney health in the community and in healthcare contexts?
5 What actions will you take in clinical practice to identify people at risk of kidney disease?

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