Fever & Intro to Pain Flashcards
1
Q
T or F: a fever is a condition
A
false - a symptom
2
Q
Define: fever
A
1) a normal response to various circumstances - usually due to viral or bacterial infection
2) controlled response where the core temp of body is increased to a new set point and a new balance of heat loss and production is established
3
Q
What oral temp classifies as a fever?
A
over 37.5 degrees C
over 38 degrees C (rectal temp)
4
Q
how long do fevers usually last?
A
3 days
5
Q
What rectal temp classifies as a fever?
A
over 38 degrees C
6
Q
What axillary (armpit) temp classifies as a fever?
A
over 37.3 degrees C
7
Q
What tympanic (ear) temp classifies as a fever?
A
over 38 degrees C
8
Q
What is the recommended way to measure temp: for children aged 0 to 2 yrs
A
1) rectal
2) axillary
- tympanic not recommended
- can damage something
- ear canal is not fully developed so you won’t get the best reading
9
Q
What is the recommended way to measure temp: for kids aged 2 to 5 yrs
A
1) rectal
2) axillary, tympanic
10
Q
What is the recommended way to measure temp: older than 5 yrs
A
1) oral
2) axillary, tympanic
11
Q
Explain the pathophysiology of a fever
A
- fever produced by pyrogens or either endogenous or exogenous origins
- endogenous pyrogens are proteins that induce fever (including interleukin-1, tumor necrosis factor alpha, interleukin-6, ciliary neurotropic factor and interferon gamma)
- exogenous pyrogens are chemicals produced by bacteria or by components of the organism (these then stimulate the release of endogenous pyrogens)
- prostaglandins of the E2 series (PGE2) are produced in response to circulating pyrogens and elevate the thermoregulatory set point in the hypothalamus
12
Q
When the hypothalamus reaches it’s new set point - how does the body temp increase to reach the new set point?
A
- vasoconstriction of peripheral blood vessels
- shivering to increase heat production
- behavioural changes (putting on more clothes/blankets)
13
Q
hyperthermia
A
increase in body temperature not due to the hypothalamus (ex. physical exertion)
14
Q
List a few risk factors for fever
A
- bacterial infection
- viral infection
- cancer
- multisystem diseases (ex. rheumatic diseases, connective tissue disorders, anything that affects more than one system)
- medications
15
Q
What age group do you want to refer if they have a fever?
A
babies less than 6 months old
16
Q
You want to refer a fever lasting > ___ hours (with or without treatment)
A
72 (3 days)
17
Q
You want to refer a fever lasting > ___ hours w/o obvious cause
A
24
18
Q
You want to refer a fever > ___ degrees C
A
40.5
19
Q
When else do you want to refer a fever?
A
- child appears ill, irritable, cries inconsolably
- child other symptoms that bother parents
- pt has persistent wheezing/cough
- pt has rash
- recently had chemo
- pt has other serious disease
- pt has recently travelled
- recently had surgery
- eaten raw/poorly cooked meat/fish
- recently started a new drug
20
Q
Signs/symptoms associated with fever
A
- sweating
- headache
- fatigue
- pain
- discomfort
- dehydration
- chills
- febrile seizures
21
Q
goals of therapy for fever?
A
- patient comfort
- reduce parental anxiety
- reduce metabolic demand caused by fever in its with CV (cardiovascular) or pulmonary disease
- prevent/alleviate fever-associated mental dysfunction in the elderly
22
Q
Why is reducing temp not a goal of therapy?
A
- because the fever is fighting off infection
- it is providing an increased temp environment so bacteria or virus cannot survive
23
Q
List some non-pharms for treating a fever
A
- remove excess clothing, blankets, bedding (keep cool and comfortable)
- increase fluid intake
- avoid physical exertion
- maintain normal room temp
24
Q
antipyretic
A
used to prevent or reduce fever
25
how do antipyretic agents work to reduce body temp?
decreases prostaglandin synthesis by inhibiting the cyclooxyegenase (COX) enzyme
26
What are the only 2 therapeutic choices for managing fever in children
acetaminophen
| ibuprofen
27
How do acetaminophen and ibuprofen help manage a fever?
reduce the hypothalamus set point
| *they do not lower normal body temp
28
Why is regular/short term use of agents recommended?
to remain consistent in treating the fever
| -intermittent use may cause swings in temp (which will put an increased metabolic demand on the body)
29
MOA for acetaminophen
inhibits the formulation and release of prostaglandins in the CNS and by inhibiting endogenous pyrogens and the hypothalamic thermoregulatory centre
30
What temp decrease can you expect from acetaminophen?
1-2 degrees C
31
Oral onset for acetaminophen
30 mins
32
Rectal onset for acetaminophen
slow onset and incompletely absorbed
33
acetaminophen: time to peak
3 hours
34
acetaminophen: duration
4-6 hours
35
acetaminophen: where is it metabolized
liver
36
acetaminophen: GI Tract?
rapidly and completely absorbed from the GI tract
37
acetaminophen: adult dosing
325 - 650 mg Q4 to 6H PRN
*max 4000 mg/day
38
acetaminophen: pediatric dosing
PO 10-15 mg/kg/dose Q4 to 6H PRN
Max:
65-75 mg/kg/day
OR
5 doses/day
*can never exceed adult dose - even if the weight calculates that you should
39
acetaminophen: safe in children?
yes - short term use tho
40
acetaminophen: safe in pregnancy and lactation
yes
41
acetaminophen: dosing adjustment may be needed for Pts with ???
renal dysfunction
*i.e. bad CrCl
42
acetaminophen & alcohol: ?
increased risk of hepatotoxicity
43
acetaminophen & enzyme inducers: ?
decreased acetaminophen levels
44
acetaminophen & warfarin: ?
chronic use can occasionally enhance warfarin's anticoagulant effect (this is rare tho)
45
NSAIDS: include ?
ASA (acetylsalicylic acid)
ibuprofen
naproxen
46
NSAIDS: pharmacological properties ?
analgesic
anti platelet
antipyretic
anti-inflammatory
47
NSAIDS: how do they work?
act on COX enzyme which inhibits prostaglandin synthesis
48
Ibuprofen: MOA
-inhibits COX enzyme in periphery and CNS and thereby inhibits prostaglandin synthesis
49
Ibuprofen: temp decrease?
1-2 degrees celsius
50
Ibuprofen: onset as an antipyretic
less than 1 hour
51
Ibuprofen: onset as an analgesic
within 60 mins
52
Ibuprofen: onset as an anti-inflammatory
less than or equal to 7 days
-peak effect is at 1-2 weeks
53
Ibuprofen: time to peak
2-3 hours
54
Ibuprofen: duration
6-8 hours
55
Ibuprofen: metabolism?
liver
56
Ibuprofen: adult dosing for fever
200-400 mg/dose Q4 to 6H PRN
| -max 1.2g/day (OTC dosing)
57
Ibuprofen: child dosing for fever
PO 5-10 mg/kg Q6 to 8H
max: 40 mg/kg/day or 4 doses/24 hr
**again cannot exceed adult dosing even if calculations based on weight say you should
58
Ibuprofen: things to consider?
- risk of kidney damage if pt becomes dehydrated so pt must stay hydrated on this med
- take with food - it can disrupt stomach lining and cause discomfort
59
Ibuprofen & ASA
decrease ASA's anti platelet effect
60
Ibuprofen & (alcohol and corticosteroids)
increased risk of GI pain/ulceration
61
Ibuprofen & antihypertensive agents (beta-blocker, ACEI, diuretics, vasodilators)
- antihypertensive effect is inhibited
| - possible hyperkalemia with ACEI and K+ sparing diuretics
62
Ibuprofen & anticoagulant
increased risk of of bleeding
63
Ibuprofen & cyclosporine
increased levels/ risk of nephrotoxicity
64
Ibuprofen & lithium, methotrexate
increased levels
65
Ibuprofen: children at greatest risk of ibuprofen related renal toxicity include ?
- dehydrated children (avoid in children with diarrhea/ vomiting)
- CVD
- preexisting renal disease
- concomitant use of other nephrotoxic agents
- those younger than 6 months
66
Ibuprofen: always take with ?
food man
67
Ibuprofen: compatible in pregnancy?
risk in 1st and 3rd trimester
| *if pt is pregnant - acetaminophen is a better choice
68
Ibuprofen: compatible in breastfeeding?
yes
69
ASA: MOA ?
inhibits the COX enzyme in the periphery and CNS
70
ASA: onset
within 1 hour
71
ASA: time to peak
3 hours
72
ASA: duration
4-6 hours
73
ASA: ok for children?
no!
| never recommend for children due to Reye's syndrome
74
Reye's syndrome
- rapidly progressive encephalopathy (disorder of the brain) with cerebral edema, hepatic dysfunction and metabolic derangements which begins several days after apparent recovery from a viral illness
- characterized by vomiting and confusion evolving to seizures and coma
- salicylate use identified as a major precipitating factor
75
ASA: adult dosing
325 - 650 mg q4 to 6h PRN
max 4000 mg/day
76
ASA: children dosing
not recommended
77
ASA & alcohol and corticosteroids
increased risk of GI pain/ulceration
78
ASA & NSAIDs, including COX-2 inhibitiors
increased risk of gastroduodenal ulcers and bleeding
79
ASA & anti-hypertensive agents (beta-blockers, ACEI, diuretics, vasodilators)
- antihypertensive effect inhibited
| - possibl ehyperkalemia with ACEI and potassium sparing diuretics
80
ASA & anticoagulants
increased risk of bleeding
| both blood thinners?
81
ASA & methotrexate
increased levels
82
ASA & probenecid, sulfinpyrazone
decreased therapeutic effect of these agents
83
ASA - always take with ____
food
84
ASA compatible in pregnancy?
Risk in 1st and 3rd trimester (at a full dose)
Compatible at low dose
85
ASA compatible in breastfeeding?
limited data
| potential toxicity
86
What is ASA-induced asthma?
onset of asthma 30mins-3 hours post ingestion of ASA
87
What is the proposed mechanism for this rxn (ASA-induced asthma) ?
decreased PG (prostaglandins) results in increased leukotrienes (important mediator in asthma and allergies)
88
Who does ASA-induced asthma affect?
5-20% of asthmatics with concomitant allergic rhinitis (AR) or nasal polyps
89
branded version of naproxen
aleve
90
standard dose of naproxen?
220mg
91
Is aleve for adults only?
yes
92
What is the dosing for naproxen?
ages:12-65
220 mg every 8-12 hrs
age: >65 (renal insufficiencies)
220mg every 12 hrs
*max 2 tabs per 24 hours
93
Onset of action for aleve?
unknown for fever
| 20 mins for analgesic affect
94
Take naproxen with food?
yes
| and water obvs
95
Naproxen in pregnancy?
compatible
96
Naproxen in breastfeeding?
not recommended
97
Don't take naproxen if ...?
allergic to ASA or other NSAIDs
98
What patients are at risk of renal failure when using NSAIDs?
- volume depletion states
- severe congestive heart failure (CHF)
- hepatic cirrhosis
- creatinine clearance < 30 mL/min
- intrinsic renal disease secondary to diabetes, nephrotic syndrome or hypertension (HTN)
99
What is used as first line therapy ?
Acetaminophen
100
Consider acetaminophen as first line treatment in patients that are:
??
- ASA-sensitive asthma
- gastritis of PUD
- inceased risk of bleeding
- pts with renal dysfunction
- CV or hypertensive patients
- multiple concurrent drug therapy
- prego or breastfeeding women (especially 3rd trimester)
