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anti-inflammatory drugs (NSAIDs), therefore, suppresses
clot formation.
As well as TXA
2
, platelets also synthesise and store
adenosine triphosphate (ATP). On activation, platelets
secrete their stored ATP, which is dephosphorylated by
exonucleotidase enzymes to sequentially form adenosine
diphosphate (ADP), adenosine monophosphate (AMP) and
adenosine. ADP acts on specific purine receptors of the P
2Y
family to cause platelet aggregation. Clopidogrel is a pro-
drug that is converted to an active metabolite by multiple
hepatic cytochrome P450 enzymes (Sangkuhl et al. 2010).
The active metabolite acts as a competitive antagonist at
P
2Y
12
receptors on platelets (Fig. 1c), thereby inhibiting
ADP-dependent aggregation (Cattaneo and Podda 2010).
Like anticoagulants, antiplatelet drugs are associated
with an increased risk of bleeding. This is particularly
significant for aspirin, which also stimulates gastric acid
secretion and inhibits duodenal bicarbonate and mucus
secretion via a reduction in synthesis of PGE
2
, leading to a
heightened risk of ulceration and bleeding. Clopidogrel has
a slow onset of action but also has a prolonged duration
(functional t
of approximately 5 days) and exhibits sig-
nificant genetic variation in its rate of metabolism (Sang-
kuhl et al. 2010). Caution must be exercised when using
antiplatelet drugs in patients who are already taking oral
anticoagulants such as warfarin (see Sect. 3.1).
Fibrinolysis—the dissolution of existing blood clots or
fibrin deposits—may be indicated where a vessel is partially
or totally occluded by a clot or where activation of the
coagulation cascade on acatheter surface has ledto formation
of a fibrin sheath or plug. The latter is more common with
indwelling catheters, such as tunnelled dialysis lines. While
clots can be disrupted mechanically, this leads to a risk of
embolism which may be avoided, or at least diminished, by
the use of fibrinolytic agents. Streptokinase, a streptococcal
plasminogen activator, has been almost completely replaced
in interventional radiology owing to its high degree of anti-
genicity, whichleads to both a rapid loss of efficacy and arisk
of acute allergic reaction to subsequent doses. The most
commonly used agents at present are alteplase/reteplase
(recombinant tissue plasminogen activators) and urokinase
(native urokinase-like plasminogen activator), although the
latter isno longerlicensed inthe UK.Plasminogen isa plasma
protein that is converted by plasminogen activators to plas-
min, an enzyme that catalyses the degradation of fibrin to
soluble fragments. Intravascular administration of alteplase
or reteplase, therefore, increases the availability of plasmin
and promotes the breakdown of fibrin meshes.
Fibrinolytic drugscarry ahigh riskof bleeding and their use
should be avoided if possible in patients with preexisting risks
such as peptic ulcer disease and uncontrolled hypertension.
In emergency situations, where life-threatening bleeding
occurs, fibrinolysis may be reversed with tranexamic acid,
a plasminogen activation inhibitor (Dirkmann et al. 2012).
2.6 Contrast Media
Iodinated contrast media are required for the visualisation
of blood vessels in catheter angiography, as well as during
CT angiography. Hyperosmolar (ionic) molecules such
as metrizoate are no longer used intravascularly. Low/
isoosmolar (non-ionic) compounds such as iopamidol
(Niopam) andiohexol (Omnipaque), as well as the non-ionic
dimer iodixanol (Visipaque), are in routine use. While
contrast media are not generally considered to be pharma-
cologically active, they do exhibit adverse effects, although
these are less frequent with non-ionic agents (Royal College
of Radiologists 2010). These effects include hypersensitiv-
ity reactions (urticaria, bronchospasm, laryngeal oedema,
anaphylaxis and delayed skin reactions) as well as hypo-
tension and nausea. Caution should be exercised when
prescribing contrast media for patients with impaired renal
function, owing to reduced rates of clearance, and the
lowest risk agents possible should be used at the lowest
possible dose.
The cautions applied to the use of contrast agents must
be taken into account when considering potential interac-
tions with medications (see Sect. 3.2).
3 Drugs Used in Management of Patients
Before and After Procedures
3.1 Oral Anticoagulants
Patients requiring vascular intervention commonly have a
high risk of thromboembolism. They may, therefore, have
been prescribed oral anticoagulants prior to procedures. Of
these, the most widely used is warfarin, although direct
thrombin or factor Xa inhibitors, such as dabigatran and
rivaroxaban, are increasingly used in its place.
Warfarin is an inhibitor of vitamin K epoxide reductase, a
hepatic enzyme which catalyses the recycling of oxidised
vitamin K to its reduced form. Reduced vitamin K (vitamin
K hydroquinone) is required for the c-carboxylation of
glutamic acid residues on a number of coagulation factors
(factors VII, IX, X and prothrombin), a posttranslational
modification which allows the proteins to bind Ca
2+
(Shearer
and Newman 2008). By blocking the recycling of vitamin K,
warfarin prevents this modification of the coagulation fac-
tors (Fig. 1b). Consequently, Ca
2+
-dependent activation of
factor X and prothrombin via both the extrinsic (factor VII-
dependent) and intrinsic (factor IX-dependent) pathways is
Drugs Used in Vascular Interventional Radiology 29
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inhibited, resulting in reduced formation of thrombin. As
thrombin both catalyses formation of fibrin from fibrinogen
and stimulates platelet aggregation via protease-activated
receptors (PAR), the reduction of thrombin formation can
cause profound anticoagulation.
Warfarin exerts its actions on coagulation factor syn-
thesis in the liver. As a result the anticoagulant effect has a
delayed onset (peak anticoagulation occurs 48 h after
administration) and also takes several days to reverse after
withdrawal of the drug. Management of patients therefore,
involves careful titration of warfarin dose with regular
measurements of prothrombin time (PT, most commonly
expressed as international normalised ratio [INR]). In the
event of excessive anticoagulation (INR[8.0, or [ 5.0 if
there is minor bleeding), warfarin should be withdrawn and
vitamin K
1
(phytomenadione) administered intravenously.
Warfarin should only be reinstated when INR is restored to
the target range.
Owing to its mechanism of action, warfarin presents a
significant risk of haemorrhage. It is also teratogenic and
can cause bleeding disorders in babies during delivery and
breastfeeding. Warfarin is extensively bound to plasma
albumin and is metabolised by hepatic cytochrome P450
mixed-function oxidases, principally CYP2C9. Pharmaco-
kinetic interactions can readily occur with other highly
plasma protein-bound drugs (e.g. aspirin, sulfonamide
antimicrobials) and other CYP2C9 substrates (including
many antiepileptics, antimicrobials and antidepressants),
usually resulting in a sudden increase in INR. As the
assembly of the tenase and prothrombinase complexes in
the coagulation cascade occurs through Ca
2+
-mediated
binding of coagulation factors to the membrane phospho-
lipids of activated platelets, any drug that inhibits platelet
activation—including aspirin and other non-steroidal anti-
inflammatory drugs—as well as drugs such as valproic acid
and methotrexate which produce thrombocytopaenia as a
side-effect, will cause significant and unpredictable aug-
mentation of the anticoagulant action of warfarin.
While orally active direct thrombin inhibitors such as
dabigatran (Hirsch et al. 2005), and direct factor Xa
inhibitors such as rivaroxaban (Eriksson et al. 2008), exhibit
fewer interactions than warfarin, they still present signifi-
cant risk of both haemorrhage and interaction.
3.2 Oral Hypoglycaemics
The risk of vascular disease is significantly raised in patients
with diabetes. Consequently, a large proportion of patients
undergoing intervention will be taking oral hypoglycaemic
drugs. Metformin remains the first-choice drug for control of
blood glucose in patients with type 2 diabetes (Royal College
of Physicians 2011), and this is therefore, a drug that will
be frequently present in the current medication of patients
undergoing vascular intervention.
Metformin is a biguanide that lowers blood glucose by a
number of mechanisms, including suppression of hepatic
gluconeogenesis via activation of AMP-activated protein
kinase (AMPK), and stimulation of skeletal muscle glucose
uptake (Krentz and Bailey 2005). It additionally contributes
to control of diabetic cardiovascular risk by reducing cir-
culating very low-density lipoprotein (LDL and VLDL)
levels. From the point of view of the vascular interven-
tionist, the principal issue in patients receiving metformin is
the impact on plasma metformin concentrations of the acute
reduction in renal clearance occurring after administration
of contrast media. As metformin is cleared predominantly
by renal excretion, contrast agent-induced short-term
impairment of renal function is associated with elevated
levels of metformin that can precipitate potentially lethal
lactic acidosis. It is recommended that metformin therapy is
stopped prior to radiographic procedures involving intra-
vascular iodinated contrast media and withheld for at least
48 h following procedures, or until normal renal function is
restored (Thomsen and Morcos 2003).
3.3 Insulin
Patients with type 1 diabetes, or type 2 diabetes in which
b-cell failure has progressed to a stage at which insulin
replacement is required, will be treated with regular injec-
tion of insulin or an insulin derivative such as insulin lispro
or insulin glargine (Mayfield and White 2004). Again, the
potential for interactions must be considered. In the case of
insulin, potentially harmful interactions may occur with a
number of drugs including aspirin (see Sect. 2.5) and ACE
inhibitors (see Sect. 3.5). These may increase the hypo-
glycaemic action of insulin by stimulating insulin secretion
or enhancing insulin sensitivity, respectively. Blood glucose
must therefore be monitored carefully in patients prescribed
aspirin and/or ACE inhibitors on discharge to allow titration
of insulin dose.
3.4 Statins
Cholesterol-lowering agents such as simvastatin are used to
reduce the cardiovascular risk of patients with elevated LDL
and/or lowered high density lipoprotein (HDL)/LDL ratio, as
well as to reduce the total risk associated with other factors
such as hypertension and diabetes. Statins act by inhibiting the
enzyme 3-hydroxy-3-methyl-glutaryl (HMG)-CoA reductase,
thereby suppressing hepatocyte cholesterol synthesis. The
resulting fall in intracellular cholesterol concentration stimu-
lates the expression of LDL receptors on the surface of
30 G. Dent and M. G. Cowling
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hepatocytes, leading to the sequestration of cholesterol from
the plasma and reduced risk of thromboembolism.
While statins do not themselves present a risk in the con-
text of vascular intervention, they exhibit significant inter-
actions with a number of antihypertensive drugs, which may
be concurrently prescribed on discharge from hospital (see
Sect. 5.3.5), and appropriate caution should be taken when
prescribing. Statins are associated with a risk of myopathy
and potentially lethal rhabdomyolysis that is increased by
pharmacokinetic interactions with antihypertensives, most
notably amlodipine, but is also elevated in common comor-
bidities such as type 1 diabetes, hypothyroidism and chronic
liver disease (Hippisley-Cox and Coupland 2010).
3.5 Antihypertensives
The association of hypertension with cardiovascular risk
indicates that a high proportion of patients undergoing vas-
cular intervention willbereceiving concurrent treatmentwith
antihypertensive drugs. First-choice drugs for treatment of
hypertension are angiotensin-converting enzyme (ACE)
inhibitors, Ca
2+
channel blockers or thiazide diuretics,
depending on ageand ethnicity(NICE 2011).ACE inhibitors,
such as ramipril, inhibit the conversion of plasma angiotensin
I to angiotensin II, which constricts blood vessels and stim-
ulates aldosteronesecretion from the zona glomerulosa of the
adrenal cortex. Inhibition of ACE therefore produces vaso-
dilation and increases Na
+
excretion. Ca
2+
channel blockers,
such as amlodipine, block entry of calcium ions via long (L)-
type Ca
2+
channels invascular smooth musclecells, reducing
vascular tone and therefore peripheral resistance. Thiazides,
such as bendroflumethiazide, cause a short-term increase in
Na
+
and water excretion, and thereby a reduction in blood
volume andvenous return,through anaction ona Na
+
/Cl
-
co-
transporter in the distal convoluted tubule. However, their
antihypertensive action appears to depend largely upon a
poorly characterised vasodilator action.
Morphine and other opioids exhibit hypotensive effects
that are exaggerated in patients treated with antihyperten-
sive medications. Particular caution must therefore be
exercised with such patients when opioid sedation is used.
The same is true, to a lesser extent, for benzodiazepines.
Similarly, organic nitrates such as glyceryl trinitrate may
produce severe orthostatic/postural hypotension when
administered to patients receiving antihypertensive medi-
cations, particularly Ca
2+
channel blockers.
ACE inhibitors increase the risk of anaphylactic reac-
tions to tissue plasminogen activators such as alteplase,
although the mechanism is unclear. They also carry a risk
of hypokalaemia that is increased in patients treated with
heparin, particularly those with renal impairment, diabetes
or severe/worsening heart failure.
4 Conclusion
The use of sedatives and analgesics, spasmolytics, antico-
agulants and thrombolytics in vascular interventional
procedures confers a requirement to understand the mech-
anisms of action of these drugs and their potential for
interaction with concurrent medications. While contrast
media are not generally considered to be pharmacologically
active, their systemic administration clearly introduces the
potential for interaction with medications, and their effects
on renal function are particularly significant in this context.
Interventionists should consider carefully the consequences
of drug choices both during procedures and after discharge.
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32 G. Dent and M. G. Cowling
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Day Case Vascular Intervention
Ounali S. Jaffer, Dean Y. Huang, and Paul S. Sidhu
Contents
1 Introduction.......................................................................... 33
2 Why Perform Day-Case Procedures? ............................... 34
3 Which Procedures are Suitable? ....................................... 34
4 Is It Safe?.............................................................................. 34
5 Staffing................................................................................... 34
6 Patient Selection................................................................... 35
6.1 Initial Assessment.................................................................. 35
6.2 Pre-assessment Clinic ............................................................ 35
6.3 Eligibility Criteria.................................................................. 35
6.4 Relative Contraindications .................................................... 37
7 Procedure.............................................................................. 37
7.1 Patient Preparation................................................................. 37
7.2 Angiographic Procedure ........................................................ 38
7.3 Following the Procedure ....................................................... 38
8 Outcome ................................................................................ 38
9 Current Status...................................................................... 40
10 Conclusion ............................................................................ 40
References...................................................................................... 40
Abstract
Over the last 20 years, there has been a change in the
management of vascular disease. Endovascular treatment
is now more likely to be considered a first-line option for
the treatment of vascular disease which would have
previously fallen within the province of more invasive
open surgery. While this change in emphasis may be
attributed to numerous factors, primarily the improve-
ment in techniques and equipment, the availability and
safety of day-case procedures have been contributory to
this development. Day-case procedures have a proven
safety record, are favoured by the majority of patients
and are cost-effective, which are particularly pertinent
given the current atmosphere of cost-control. Within this
chapter we shall discuss the necessary framework
required to establish an effective and efficient day-case
service. A particular emphasis will be placed on
appropriate patient selection, the benefits of defined
clinical roles and the required infrastructure to allow
optimum safety, as well as effectiveness. We shall
describe the benefits and detail-associated complication.
The reader should be informed on the available evidence
on day-case procedures, how to establish a service
and the current status and possible future direction of
day-case procedures.
1 Introduction
Over the last 20 years there has been a change in the
management of vascular disease, with endovascular treat-
ment, as opposed to open surgery, gaining wider acceptance
as a preferred therapy for many different vascular diseases.
From the early days of basic balloon angioplasty to the
current complex deployment of vascular stent grafts, min-
imally invasive methods have transformed the management
of vascular disease. An ever increasing recognition of the
merits of day-case procedures has been instrumental in this
O. S. Jaffer D. Y. Huang P. S. Sidhu (&)
Department of Radiology,
King’s College London,
King’s College Hospital,
Denmark Hill, London,
SE5 9RS, UK
e-mail: paulsidhu@nhs.net
M. G. Cowling (ed.), Vascular Interventional Radiology, Medical Radiology. Diagnostic Imaging,
DOI: 10.1007/174_2012_537, Ó Springer-Verlag Berlin Heidelberg 2012
33
https://t.me/med1917
continuing advancement. Day-case surgical procedures are
common place today, and in interventional radiology, day-
case procedures are not only safe but have a positive impact
on patient well-being, patient throughput and overall costs.
2 Why Perform Day-Case Procedures?
As endovascular therapy is minimally invasive and com-
monly performed without anaesthesia, the circulatory and
metabolic consequences of open surgery, as well as the
adverse effects of anaesthesia are avoided. A larger number
of eligible patients, along with a continuous improvement of
equipment, techniques and approach in angiography have
facilitated a continuing increase in the volume of proce-
dures undertaken on a day-case basis.
In the current economic climate, fiscal prudence and cost-
effective management are necessary considerations given
the mounting constraints on medical resources. Tradition-
ally, patients undergoing peripheral angioplasty would have
been admitted to the hospital for overnight observation.
However, many hospitals are often running at near maxi-
mum capacity and inpatient beds are at a premium. Limiting
unnecessary admissions and maximising resources therefore
seems desirable. Various health economic studies consis-
tently report lower costs for patients undergoing day-case
interventions compared to an overnight admission. Even
allowing for the initial outlay for changes in infrastructure
and staffing, the differences remain significant. Huang et al.
(2008) demonstrated costs of £131 for day-case procedures
compared to £318 for an overnight stay, while Akopian and
Katz (2006) calculated a same day discharge fee of $320 as
opposed to $1,800 charge incurred for an overnight admis-
sion. Less dependence on the availability of a hospital bed
not only minimises cost, but also allows optimal planning
and utilisation of radiological intervention lists. The disap-
pointment of cancellation due to inadequate capacity is
avoided and the waiting lists for procedures are reduced. The
Radiology Department gains control of the admission.
Optimising patient satisfaction is an important goal of
any service; when auditing patient perception, day-case
procedures have consistently recorded particularly high
levels of patient satisfaction and are considered a more
convenient and favourable option for the vast majority of
patients (Lemarbre et al. 1987).
3 Which Procedures are Suitable?
When setting up a day-case interventional radiology unit, the
complexity of the service should reflect the incorporated
infrastructure, operator ability and available support.
Current literature demonstrates that aortoiliac, iliofemoral,
infrapopliteal, femoropopliteal bypass graft, renal, visceral
and subclavian angioplasty, pulse-spray thrombolysis and
atherectomy have all been performed successfully on a day-
case basis (MacDonald et al. 2002;Lombardietal.2002;
Kruse and Cragg 2000). Although outpatient iliofemoral
artery stenting is well established, the recent development in
stent technology has coincided with the stenting of more
peripheral leg and visceral arteries, and these procedures may
well also beperformed safely on anoutpatient basis (O’Brien-
Irr et al. 2008). Urological and gynaecological procedures
such as varicocele embolisation, uterine fibroid embolisation,
percutaneous nephrostomy with ureteric stent insertion, as
well as venous access procedures including tunnelled lines,
peripheral inserted central catheters (PICC) lines, line strip-
ping and inferior vena cava filter placement have all been
performed as day-case procedures (MacDonald et al. 2002;
Siskin et al. 2000; Gray et al. 1996; Maher et al. 2008).
Dialysis graft intervention can be successfully achieved if
procedure dates are coordinated with the renal unit (to allow
for dialysis); this can vary from more conventional treatment
of arterial-venous fistula stenosis, to the reported percutane-
ous mechanical thrombectomy and thrombolysis of occluded
dialysis grafts (Middlebrook et al. 1995).
Overall, the clinical selection of appropriate patients for
day-case procedures can be effectively determined given the
perceived, as well as the quoted risks and benefits. As will be
discussed, practically itisoften theparticular circumstance of
the patient as opposed to the technical complexities of the
procedure that predominates the decision making process.
4 Is It Safe?
A number of reports indicate that angiographic procedures
may be safely performed as a day-case procedure (Kruse
and Cragg 2000; Young et al. 2002; Gradinscak et al. 2004;
Soulier-Parmeggiani et al. 1992). Angiographic procedures
do, however, carry a small but definite risk as many patients
with peripheral vascular disease will have associated and
often varied medical co-morbidity. The key to successful
practice therefore, is the establishment of defined clinical
roles, careful patient selection and agreed protocols.
5 Staffing
A succinct and organised framework in which to operate a
day-case facility is particularly important. With increasing
constraints on the clinical time of radiologists, a nurse-led
radiological unit for the overall management of patient care
is an attractive and cost-effective strategy. As interventional
radiology has specific requirements which may not neces-
sarily be incorporated into the more general nursing
34 O. S. Jaffer et al.
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curriculum, it is important to establish a dedicated training
programme specific to radiological nursing practice. This
should ideally involve an external assessment with acqui-
sition of a formal qualification (diploma or degree) and be
supplemented with structured in-house training. The train-
ing should allow the radiology nurses to enhance their
overall knowledge and gain the skills required to assess,
implement and evaluate patient care. Within this structure,
the radiology specialist nurses (RSN) would become
responsible for pre-procedure assessment, as well as
appropriate patient care before, during and after any inter-
ventional procedures including angiography.
6 Patient Selection
6.1 Initial Assessment
All patients need to be initially assessed in an outpatient
clinic by a vascular surgeon or a physician with a specialist
interest; if the interventional radiologist can also be present
this aids considerably with patient selection. During the
consultation, the nature of the interventional procedure with
an explanation of the potential benefits and the known risks
must be discussed with the patient. A full medical history
including indications for the procedure, co-morbidities, list
of current medications, allergies and prior relevant surgical
and endovascular procedures should be detailed. After
appropriate consultation and possible investigation, which
may include imaging (Doppler ultrasound, Computed
Tomography angiography (CTA) or Magnetic Resonance
angiography (MRA)), onward referral of suitable patients to
a dedicated pre-assessment clinic can be undertaken.
6.2 Pre-assessment Clinic
Huang et al. (2008) demonstrated that with an appropriate
level of training, pre-procedural assessment can be suc-
cessfully delivered by experienced nursing staff. In smaller
centres with less capacity, the involvement of the junior
vascular surgical staff may prove to be the only feasible
option. In order to establish a unified approach, it is
advisable to devise a pre-set protocol (Table 1) with cross-
consensus agreement between all faculties involved in
patient management. This will establish clarity and avoid
ambiguity, especially in the pre-assessment setting.
If not already organised, the patient should have blood
work-up with a full blood count, urea and electrolyte mea-
surement and coagulation screen. The pre-procedural
assessment clinic also allows for a further opportunity to
discuss the planned angiographic procedure and address
any patient queries. In view of this, easy access to an
interventional radiologist for queries requiring more detailed
explanation is preferable. All information should be recorded
in a standardised document for each patient, listing findings
from the pre-angiographic clinic, separate from the patient’s
hospital notes to be added later following the procedure.
By the end of the consultation the patient should be
aware of the nature and potential benefits and risks, as well
as the specific requirements for the given procedure. As the
volume of information can be quite substantial, it is rec-
ommended that patients are issued with locally derived
information leaflets tailored to their specific procedure. In
order to maximise the efficiency of services, it is important
that the final consultation on the day of the procedure is
largely a confirmation of the facts already presented. Often,
the more commonly encountered patient enquiries will be
adequately addressed in the information leaflets. As well as
information regarding the actual procedure, the leaflets must
include details regarding the logistics (e.g. map of depart-
ment location, opening times and telephone number) for the
immediate pre-procedure period. These leaflets therefore
become an invaluable resource for the patient and contrib-
ute to the smooth throughput of cases.
6.3 Eligibility Criteria
The main benefits of day-case intervention can be lost if
adequate pre-planning is not undertaken. It is important to
identify those patients who are not only medically but also
socially suitable. Often, the conversion of outpatient to inpa-
tient procedures can be problematic due to the lack of pre-
arranged facilities. It is therefore mandatory that certain
issues are carefully considered prior to the attendance of the
patient for the procedure; co-operation with the vascular sur-
gery team to facilitate admission should be well established.
The patient must be accompanied by a capable adult who
comprehends the nature of the procedure and the impor-
tance of continuous supervision. The carer must demon-
strate an ability to follow instructions and recognise
potential complications. Ideally, the patient needs to be
supervised for up to 24 h after the procedure. The allocated
carer should also ensure an appropriate method of trans-
portation is arranged post-procedure; a car to return home is
essential and an ambulance may be needed in some cases.
The lack of an adequate support network will preclude the
patient from a day-case procedure.
It is imperative that the patient has sufficient capacity to
understand the nature of any complication and demonstrate
an ability to respond accordingly. Confused or mentally
impaired patients are admitted for an inpatient procedure. If
given sedation, the patient’s mental status and motor
function must have returned to a pre-procedure baseline
prior to discharge.
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Table 1 Pre-assessment check list for the radiological specialist
nurse (Reproduced with permission of the Editor, British Journal of
Radiology from Huang et al. (2008))
Care Document: Part I
Patient assessment
Performed in Radiology Day-Case Unit (RDCU) and completed by
Radiology Specialist Nurse (RSN)
Have you had this type of examination before?
Are you taking any medicines? (tablets, patches, inhalers, injections)
Have you any allergies? (previous contrast reactions, drugs, plasters)
Have you had any serious illnesses in the past?
Do you have high blood pressure?
Do you have asthma?
Do you have anaemia or any other blood disorder?
Do you have kidney disease?
Do you have diabetes mellitus? (Ask if on metformin)
Are you or could you be pregnant? (Female patients)
Physician clerking
From clinical notes and transcribed to RDCU notes by RSN
History of claudication and risk factors
Past medical history
Drug and allergy history
Social history
Examination of respiratory and cardiovascular systems (including
peripheral pulses)
Screening investigations (full blood count, clotting, renal and liver
function, sickle cell test, CXR, ECG; as required)
Vascular laboratory assessment (Results)
Patient check list
Patient made aware of socio-domestic requirements
24 h accompaniment by responsible adult
Transport by car or taxi
Availability of GP/nursing back up
Reasonable access to a telephone
Patient made aware of medico legal requirement:
Understanding and acceptance by the patient of his/her obligations to
the RDCU concerning his/her procedure welfare
Patient demonstrates an understanding of the procedure
Patient pre-angiography information sheet given (see Appendix 2)
Clear fluids from midnight
Date for day-case angiogram (DCA)
Given to patient
Entered in the DCA diary
Referral doctor informed
Surgical admissions informed
Table 1 (continued)
Care Document: Part II
Results
Pre-angiographic screening investigations documented in day-case
notes
Completed by the RSN and/or Radiologist
Pre-procedure assessment
New health problems
Ill today?
Eaten in the last 4 h
Last menstrual period (female patient)
Responsible adult for journey home
Responsible adult for 24 h after DCA
(If negative response to any of the above, new date made for DCA)
Blood pressure, pulse, temperature, weight, oxygen saturation
Arterial puncture site preparation
Femoral and distal pulses recorded
Consent obtained by Radiologist
Procedure details
Procedure technique
Drugs administered, including contrast volume
Procedure result
Any further action
Procedure complications
Instructions
Post-procedure assessment
Time catheter removed
Time to haemostasis
Haematoma
Blood pressure, pulse, oxygen saturation
Puncture site inspection
Any complications recorded
Discharge check list
Mobile
Passed urine
Any discharge medication prescribed
Appropriate discharge letters
Surgical follow-up arranged
Patient aware of puncture site wound care
Patient aware of action in case of complications
Patient agreed to telephone RSN at RDCU by 11am the next day
Follow-up at 24 h
General well-being
Puncture site
(continued)
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The patient must be free of concurrent serious medical
illness which may significantly increase risk of complica-
tion, such as unstable heart disease.
Confirmation of close access to medical facilities should
be sought, especially if patients are travelling long distances
to attend tertiary referral centres. If this is not guaranteed,
the patient should be encouraged to arrange alternate
overnight accommodation. Adequate communication links
with the interventional facilities must be given to the patient
and carer prior to discharge. This can allay concerns about
any minor enquiries which may arise and hence avoid
unnecessary hospital attendance.
6.4 Relative Contraindications
Ultimately, the key to a successful outpatient service will be
dependent on well considered patient selection. While some
authors surmise that all patients should have an equal
probability of attaining same day discharge, others advise
caution in given clinical situations (Huang et al. 2008;
Akopian and Katz 2006). It should be appreciated that the
majority of the following apparent contraindications are
relative rather than absolute.
Those with poorly controlled hypertension have an
increased incidence of haematoma and bleeding complica-
tions at puncture sites. If recognised at a pre-assessment
level, appropriate referral should be sought with medica-
tions adjusted prior to intervention. If patients present
hypertensive on the day of the procedure then the individual
merits of the case should be considered. In such cases, it has
been shown that the use closure devices for puncture sites
can be undertaken without increased risk of complication
(MacDonald et al. 2002).
The diabetic population by virtue of the disease process
represent a significant proportion of most interventional
department caseloads. Diabetic patients are four times more
likely to develop peripheral vascular disease and five times
more likely to develop critical limb ischaemia than the
general population (McNeely et al. 1995). Those well
controlled on diet, oral medication or insulin can be suc-
cessfully treated as day-case procedures. Specific measures
such as the monitoring of serum glucose levels, especially
in the peri-procedure period, must be considered a manda-
tory aspect of the care pathway. Admittance of the patient
should be sought in those who demonstrate labile glucose
levels on monitoring. As defined by the current guidelines
issued by the (Royal College of Radiologists 2010), patients
on Metformin need not stop their medication after contrast
administration if serum creatinine is within the normal
reference range and/or the estimated glomerular filtration
rate (eGFR) is above 60 ml/min. If renal function is outside
of this range, then a decision to stop Metformin for 48 h
should only be made after consultation with the referring
clinic. In cases where serum glucose instability is identified
at pre-assessment, appropriate review by the specialist
Diabetologist to optimise glucose control is advisable. Due
to the often encountered complexity of this subset of
patients, the benefits of a well organised multi-disciplinary
team should not be underestimated, with an improvement in
overall care using this approach well proven.
The risk of contrast nephrotoxicity is related to the extent
of pre-existing renal impairment, dose of contrast agent
administered and the state of hydration of the patient.
Congestive heart failure, age of [70 years, concurrent
administration of nephrotoxic drugs and the combination of
renal impairment with diabetes are all recognised risk fac-
tors (Morcos et al. 1999; Morcos 2005). Risk reduction
measures must be instigated in those patients thought to be
susceptible. Although a guide level of eGFR below 60 ml/
min has been used to indicate renal impairment, a defined
level to trigger precautionary therapy is often derived
locally after consultation with the Nephrologists. Control-
ling the dose of contrast medium administered and adequate
hydration both prior and after the procedure are two mea-
sures currently advised for impaired renal function. If intra-
arterial contrast is administered, fluid hydration should be
given intravenously and therefore, inpatient treatment is
often necessary (Morcos 2005). Patients already in end-
stage renal failure and on renal replacement therapy can be
successfully managed as day-case procedures. For this
particular subgroup, dialysis sessions need to be appropri-
ately coordinated with the procedural date.
Anticoagulant treatment need not necessarily be regarded
as anexclusion criterion. MacDonald et al.(2002)successfully
performed day-case procedures, often using closure devices, if
the patient’s international normalised ratio (INR) was under
2.5 and had been stable for 2 months or more. Patients with
coagulopathies or electrolyte abnormalities that require treat-
ment, however, should be hospitalised untill fully corrected.
Complications that occur during or after the procedure,
including haematoma, anuria, persistent nausea and vomit-
ing, significant arrhythmia or haemodynamic instability,
require careful observation with subsequent inpatient
admission determined by on-going clinical concern or
non-resolving symptomatology (American College of
Radiology—Society of Interventional Radiology 2007).
7 Procedure
7.1 Patient Preparation
As patients undergoing intra-arterial treatment normally
require a set period of observation post-procedure, admit-
tance as well as treatment should be scheduled for the
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morning list. Venous therapies may allow more flexibility
but each case needs to be judged individually.
All patients must be starved for a minimum of 4 h prior
to the procedure. On the day, patients should arrive at least
30 min before their scheduled slot for treatment. In this
period, a brief reassessment by the specialist nurse should
be conducted with adequate social support confirmed and
absence of clinical deterioration requiring inpatient admis-
sion established. All screening test results must be
rechecked and baseline observations obtained (i.e. pulse
rate, blood pressure and oxygen saturation), with the find-
ings recorded in a standardised day-case document.
Informed consent can then be finalised before the patients
are transferred to the interventional suite.
7.2 Angiographic Procedure
All procedures should be conducted in a dedicated
interventional suite using the appropriate equipment
(see ‘‘Equipment and Environment’’) with standard depart-
mental angiographic practice adhered to. A patient’s elec-
trocardiogram, blood pressure and pulse oximetry require
monitoring by a nurse during the procedure with the findings
recorded in the day-case document. For patients with diabe-
tes, the blood glucose levels need to be repeatedly checked
and recorded. All medications, including the use of local
anaesthetic, heparin, vasodilators, pain relief and sedatives,
as well as the type and volume of contrast used must also be
documented.
Accurate description of the procedure including the
method of puncture closure should be detailed in the day-
case document by the performing radiologist.
7.3 Following the Procedure
Once the procedure is complete, patients can be transferred
from the interventional suite to the day-case unit. A formal
hand-over between the RSN present during the procedure
and the supervising day-case unit RSN should be performed
in all cases. The unit would ideally be in close vicinity of the
interventional suite to maximise efficiency as well as safety,
with the attending interventionalists within close proximity.
The lay-out of the unit, including necessary equipment, has
already been addressed (‘‘Equipment and Environment’’).
However, specific requirements to incorporate day-case
patients would normally include dedicated lockers and a
facility such as a waiting area for the designated carers.
Monitoring of vital signs, puncture site and where rele-
vant, peripheral pulses, should be performed every 15 min
in the first hour, every 30 min for the next hour and
hourly thereafter. If access was by the femoral route with
haemostasis achieved by manual compression, patients
must be kept supine and gradually mobilised after a 2–4 h
period. Commonly, mobilisation will be achieved following
a gradual step-wise method, with the patient initially told to
lie supine, followed by sitting upright in bed or a chair and
then finally mobilised. If a closure device was used,
mobilisation can often be achieved earlier with certain
studies reporting on successful immediate mobilisation
(Hvelplund et al. 2011). It remains prudent, however, to
adhere to the manufacturer’s recommendations and to
address each case within the clinical context. Brachial or
radial arterial access, venous procedures and haemodialysis
fistula treatment often allow more rapid ambulation and
may not need the same prolonged observation period; hence
locally derived guidelines should be detailed for individual
procedures.
Patients without complication can be discharged under
the supervision of an accompanying adult. Clear oral and
written instruction regarding wound care and activity
should be detailed, with the immediate management of
bleeding at the puncture site explained. The patient must
have an unequivocal understanding of what would require
emergency treatment (e.g. pulsatile bleeding), as opposed to
enquiries which should be directed to the day-case unit. As
most day-case units will only operate within conventional
working hours, it is desirable for a secondary point of
contact, such as the vascular surgical wards are able to
advise during the ‘out-of-hours’ period. The direct tele-
phone numbers for both these respective facilities should be
documented on the discharge sheet.
Once discharged, the day-case document should be filed
in the patient notes so as to be available to the referring
clinician. A copy should also be sent to the General Prac-
titioner and given to the patient. If there is an electronic
recording system established within your institution, then a
detailed discharge summary must be compiled and again
distributed in a similar fashion.
For angiographic procedures, a follow-up clinic
appointment is routinely made 4–6 weeks after the proce-
dure. When initially setting up a day-case service, it may be
beneficial to operate a telephone follow-up 24 h post-pro-
cedure. By using a standardised questionnaire, pertinent
information regarding patient satisfaction and perception, as
well as complications can be gleaned and subsequently
audited.
8 Outcome
The validity of a service will always rely heavily on the
safety and efficacy profile reported. A strong argument for
day-case procedures arises from the known dynamics of
recognised complications. Most complications such as
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