Utilising the objective data gained through cue acquisition I went on to perform a
musculoskeletal exam of Mrs. Smith’s left lower limb. Upon inspecting Mrs. Smith I noted,
swelling to her entire calf with bruising to the medial aspect. Palpating her calf revealed that it
was firm, cool to the touch, and with a very faint pedal pulse. Mrs. Smith complained of 10/10
pain on palpation of the entire calf muscle with reduced sensation to her foot and a capillary
refill time of 3 seconds. Her left leg was swollen, painful and appeared ischemic. I compared
the swelling of her left leg to the right by measuring the circumference of both limbs 10
centimetres below the tibial tuberosity and 15 centimetres above the upper limit of the patella.
She also had oedema and dilated superficial collateral veins on the left side. There was also
tenderness on deep palpation of the popliteal fossa of her left limb. These examination
findings further suggested deep venous thrombosis. According to the underpinning theory,
these further comprise the “patterns” of presentation of deep venous thrombosis.
However, some signs such as a firm, cool, and ischemic limb that has a poor pedal
pulse would point to other clinical diagnoses, especially compartment syndrome. Therefore, I
also considered other conditions that would explain Mrs. Smiths’s examination findings.
According to the underpinning theory, these would now comprise the underlying “structures”
that comprise the cause of the symptoms. Mrs. Smith could have had other medical problems
like a fracture of the tibia or fibula following unnoticed trivial trauma. At her age, she could
be having postmenopausal osteoporosis, which would weaken her bones, and make them
more liable to fractures when subjected to minor trauma. Other than these, she could have
cellulitis of the affected calf which irritates the cutaneous nerves and trigger the severe pain
sensation. Other less relevant possibilities were baker’s bursitis. These diagnostic hypotheses
were the alternative ones other than DVT.
Tentative hypothesizing refers to inferring a property of the case at hand (that is the
patient) from previous experience of similar cases. A tentative diagnosis is one which is worth ADVANCED HEALTH ASSESSMENT AND DIAGNOSIS 7
testing and is formulated through closed questioning (Thompson and Dowding 2002). For
Mrs. Smith; the description of the pain as constant, intense and unresponsive to co-admol are
the most important factors that point to the hypothesis that she has deep venous thrombosis.
On the other hand, intuition is judgment without rationale (Muoni 2012). Thompson and
Dowding (2002) assert that intuition is a skill that the nurse acquires through previous
experience, and it plays a significant role in expert nursing practice. My first deduction, that
is, Mrs. Smith had deep venous thrombosis, was by intuition. Most of my previous patients
who had calf pain and swelling were diagnosed with deep venous thrombosis.
Additionally, nurse theorists describe intuition as spontaneous and irrational thinking
process that develops out of expertise and experience (Muoni 2012; Thompson and Dowding
2002). Thompson and Dowding (2006) also assert that intuition requires the nurse’s
involvement with the client, in order to consider the client’s story and how the illness has
affected their lifestyle, in order for the nurse to view the patient’s situation according to his or
her clinical experience and expertise. Intuition is closely related to heuristics, which involves
the experience-based methods for problem solving (Muoni 2012). Being different from the
clinical reasoning methods proposed by Thompson and Dowding (2002), heuristics speeds up
the process of finding a suitable solution. In other words, heuristics is a mental short cut for
reducing the workload of decision making (Muoni 2012). As in Mrs. Smith’s case, any health
practitioner would consider the diagnosis of deep venous thrombosis in a patient with intense
calf pain, swelling and erythema.
However, intuition alone would have led to a less satisfactory diagnostic hypothesis
for Mrs. Smith’s case. I had to apply correct cue interpretation in order to arrive at a
successful diagnosis (Thompson and Dowding 2002). Correct cue interpretation involves the
review of evidence (symptoms and hypotheses) through hypotheses evaluation. This involves
rechecking the evidence before planning and implementation. The evidence is examined to ADVANCED HEALTH ASSESSMENT AND DIAGNOSIS 8
further support the diagnostic hypothesis or to refute it. The nurse then selects the evidence
preponderant hypothesis to guide treatment planning and implementation (Muoni 2012;
Thompson and Dowding 2002).
Going back to Mrs. Smith’s case, I reconsidered my tentative diagnosis of DVT after I
found out that Mrs. Smith was on anticoagulation therapy. Through hypothesis evaluation, I
concluded that DVT would be less likely in her case because she was already on prophylactic
therapy. However, I also still considered this diagnostic hypothesis because the warfarin may
have been started after she developed DVT. Nevertheless, I changed my tentative diagnostic
hypothesis to a differential diagnosis of DVT. I started collecting cues that would suggest a
differential of DVT, of which, compartment syndrome was the closet.
Differential diagnosis of deep venous thrombosis other than compartment syndrome
Deep venous thrombosis is an entity in the group of diseases called venous
thromboembolism. It involves the presence of a blood clot (thrombus) in one of the deep
veins through which blood flows back to the heart. It commonly occurs in the veins of the
lower limbs, especially at the level of the calf and the thigh (Makris & Watson 2001). The
differential diagnoses of DVT include conditions that present with the same symptoms and
Cellulitis of the lower limb is the commonest medical condition that would present
with calf pain and swelling; resembling the presentation of deep venous thrombosis (Makris
& Watson 2001). Cellulitis is an acute non-necrotizing inflammatory process involving the
skin and subcutaneous tissues while sparing thee deep fascia and muscles. It presents as
localized swelling, erythema, pain, tenderness and warmth. It does not produce abscesses,
purulent drainage or ulceration (Makris & Watson 2001; Stevens et al 2005). Cellullitis has
been found to more common among the geriatric population; to which Mrs. Smith belongs
Superficial thrombophelibitis is also a common differential diagnosis for deep venous
thrombosis of the lower limb. It is an inflammatory-thrombotic disorder that develops when a
thrombus occurs in a superficial vein (Tovey & Wyatt, 2003). The thrombus then acts as a
nidus for bacterial infection. As the bacteria colonise the thrombus they cause phlebitis of the
vein and surrounding tissue (Scottish Intercollegiate Guidelines Network, 2010; Tovey &
Wyatt, 2003). It mostly affects the varicosities of the great saphenous vein, but it can also
affect the lesser saphenous vein. Authorities postulate that it is associated with one component
of the Virchow’s triad; that is, turbulent blood flow or stasis, changes in blood components
that lead to hypercoagulability, and intimal damage (following trauma, inflammation or
infection) (Mclachlin, Richards & Paterson 1962; Meissner et al. 2002). Superficial
thrombophlebitis may present with swelling, redness and tenderness that is distributed along
the course of the vein. Bleeding can also develop from the infected site. Superficial
thrombophlebitis may progress to involve the deep veins (Mclachlin, Richards & Paterson
1962; Scottish Intercollegiate Guidelines Network, 2010; Tovey & Wyatt 2003; Verlato et al.
A ruptured baker’s cyst is the most common cause of swelling in the popliteal fossa. It
arises from the escape of synovial fluid from the knee joint cavity and its accumulation in the
gastrocnemio-semimembranosus bursa, thus causing distension. An inflamed baker’s cyst
may present with pain, redness and tenderness especially if the inflammation spreads to other
soft tissues (Baker 1994). It is commonly precipitated by osteoarthritis of thee knee joint in
the elderly (Baker 1994; Pinnamaneni & Thomas 2008). The patient in this case may have
developed a baker’s cyst that occludes the venous drainage of the lesser saphenous vein
causing subsequent thrombophlebitis.
The old cart mnemonic describes seven attributes of patient’s symptoms, especially
pain, which is used to take a detailed patient history. These attributes include onset, location,
duration, and character, aggravating factors, radiation, timing and severity (Henderson,
Tierney & Smetana 2012). On the other hand, the wells criteria are a validated clinical
prediction for the pre-test probability of DVT. It classifies patients to be either at high,
moderate or low risk of having DVT, on the basis of ten factors that give a total score ranging
from -2 to 9. A score of less than 2 implies a low probability for DVT while a score of
greater than 2 implies that DVT is likely. The pertinent factors include active cancer, limb
swelling of more than 3cm compared to the contralateral limb, collateral superficial veins,
pitting oedema of the limb, swelling of the entire limb, localized tenderness along the course
of a deep vein, recently bed-ridden, previous deep vein thrombosis and recent paralysis or
immobilization of the affected limb (Scottish Intercollegiate Guidelines Network 2010).
According to Maelen and Raina (2007) the wells criteria have moderate sensitivity and
poor specificity such that it has limited use in primary care diagnosis of DVT. They
established that the Wells criteria have a sensitivity of 82% at 95% confidence interval, a
specificity of 22.5% and a pre-test probability of 12%. The current gold standard test for DVT
is venography, which is both expensive and invasive. Therefore, other non-invasive tests like
D-dimer testing and venous ultrasonography have been validated for DVT. However they
have to be combined in order to improve the pre-test probability (Mcrae & Ginsberg 2004).
As part of my hypothesis evaluation process, I considered that DVT may be unlikely
in Mrs. Smith’s case because she was already on warfarin. She may have already developed a
non-resolving thrombus in the deep veins of the calf but the fact that she was on warfarin
down-played DVT as a formidable diagnosis. Thus, I had to consider the differential
diagnoses of DVT because anticoagulation reduces the risk of DVT. Compartment syndrome
was the next condition that would present with intense unremitting calf pain with associated ADVANCED HEALTH ASSESSMENT AND DIAGNOSIS 11
firmness, tenderness, and coldness of a limb. It would be common on calf region due to the
little room for expansion in calf fascial compartments (Rizzoli et al. 2013).
Compartment syndrome
Acute compartment syndrome involves raised tissue pressure in a closed fascial
compartment, which exceeds the perfusion pressure and leads to nerve and muscle ischemia.
It commonly occurs in the limbs following a trauma, such as a fracture. This patient,
considering her age, may have suffered a fracture of the tibia or fibula following an unnoticed
trauma. Long standing postmenopausal osteoporosis in may have led to bone weakness and
predisposition to fractures following trivial injury. This then leads to an insidious onset of
compartment syndrome (Feliciano et al. 1988; Rizzoli et al. 2013). When tissue pressure
exceeds the venous pressure, blood flow out of the compartment is impaired. This leads to
accumulation of metabolic waste products, resulting in severe pain and distal sensory loss due
to nerve irritation. The pain is deep, aching in nature and is aggravated by both passive and
active muscle contraction (Feliciano et al. 1988). At a later stage, compartment syndrome
presents with loss of arterial pulse distal to the pathological site, because the tissue pressure
finally exceeds the arterial pressures thus occluding the arteries. Late manifestations also
include peripheral paresis and hypoesthesia. The patient usually describes a feeling of
swelling and tightness over the affected region (Feliciano et al. 1988; Rizzoli et al. 2013).
Physical examination of a limb affected by compartment syndrome is cantered on the
five P’s of limb ischemia. These include pain, pallor, pulselessness, poikilothermia and
paresthesia. However these signs point to late stage disease, when irreversible and extensive
tissue damage may have occurred. A firm limb with a wooden feel is also a very important
sign of acute compartment syndrome (Feliciano et al. 1988; Howard, Mohtadi, & Wiley
International normalised ratio ADVANCED HEALTH ASSESSMENT AND DIAGNOSIS 12
INR is the best method for testing blood hypercoagulability. It provides a standard
means of estimating the effect of oral anticoagulants, such as warfarin, by comparing a
patient’s prothrombin time to a control value (the average of prothrombin times of about 20
healthy subjects). Prothrombin is the time it takes for plasma to clot (Jackson, Esnouf &
Lindahl 2003). It also incorporates an entity called international sensitivity index which
compares the accuracy of machines that test clotting time to the international standard. This
way, prothrombin time results from various laboratories across the world can be compared
(Tripodi 2004). The INR formula is:
INR = (prothrombintest / prothrombincontrol) ISI
In Mrs. Smith’s case, INR would be important to detect hypercoagulability. At INR of
below 2, the risk of thromboembolism is high and may precipitate deep venous
thromboembolism, and subsequent cardiac arrest, pulmonary embolism or ischemic stroke
(Feliciano et al. 1988; Howard, Mohtadi, & Wiley 2000; Rizzoli et al. 2013). Therefore, I
tested her INR to rule out ongoing or impending venous thromboembolism (Feliciano et al.
1988). The INR value of 12 was extremely out of range. The normal INR values range
between 2.0 and 3.0 (Tripodi 2004). The INR of 12 would imply that Mrs. Smith is at a very
high risk of bleeding following trivial bruising. It further suggests that Mrs. Smith has
developed over anticoagulation from her warfarin anticoagulant therapy (Cruickshank, Ragg
& Eddey 2001). The sensitivity of INR for detecting DVT is estimated at 100% when the INR
is greater than 1.7, with a specificity of 90.5%. However, the sensitivity drops to 62.5% when
the INR value is below 1.7 (Jack & Agnes 2002).
Mrs. Smith case was an interesting way of breaking down a clinical case according to
the underpinning theory. Her symptoms, which would be the events in the theory, strongly
supported the hypothesis that she had acute deep venous thrombosis. This hypothesis was ADVANCED HEALTH ASSESSMENT AND DIAGNOSIS 13
further supported by the physical examination findings. Previous studies on deep venous
thrombosis describe these clinical features to be characteristic of DVT; thus they comprise its
pattern of presentation. However, the cause of the problem could have been a different
condition which drove me to probe further through investigational findings. Specifically, the
high INR findings steered the diagnosis away from DVT prompting investigations for the next
major medical condition that would mimic DVT, compartment syndrome. Thus, I examined
Mrs. Smith’s vase systematically until I arrived at the most likely diagnosis.
1.BAKER, W. M., ‘On the formation of synovial cysts in the leg in connection with
disease of the knee-joint.1877’, Clinical Orthopaedics and Related Research, 299
(1994), 2-10
2.CRUICKSHANK, J., RAGG, M. and EDDEY, D., ‘Warfarin toxicity in the
emergency department: recommendations for management’, Emergency Medicine
(Fremantle, W. A.), 13/1(2001), 91-7.
3.DEPARTMENT OF HEALTH, Evaluation of Extended Formulary Independent
Nurse Prescribing: Executive Summary (London: Department of Health, 2005).
4. DEPARTMENT OF HEALTH, Modernising Nursing Careers: Setting the Direction
(London: Department of Health, 2006).
5. DEPARTMENT OF HEALTH, Trust, Assurance and Safety: The Regulation of
Health Professionals in the 21st Century (London: Department of Health, 2007).
KENNETH L. MATTOX, K. L., ‘Fasciotomy after trauma to the extremities’,
American Journal of Surgery, 156/6 (1988), 533-6. ADVANCED HEALTH ASSESSMENT AND DIAGNOSIS 14