Clinical Management - Outpatient DVT management

    Kyne Anne, Gleeson Aidan, Boland Barry,  Outpatient DVT management, World of Irish Nursing,  10 (10) November 2002, pp 38-39.

Outpatient management of DVT patients at Beaumont Hospital is succeeding in freeing up inpatient beds for more acute conditions

IN recent years there has been an increase in emergency admissions and nurse shortages which has led to a national bed crisis with patients waiting in accident and emergency departments for up to 72 hours for admission. Many medical patients are now being cared for in surgical wards thereby reducing the number of surgical procedures carried out and increasing the waiting lists.

New practices need to be developed in hospitals to allow treatment of inpatients as outpatients in order to release beds for more acute conditions. One such practice has developed in a Dublin teaching hospital is the outpatient management of deep venous thrombosis (DVT) patients.

Background

Historically in Ireland, patients with DVT have been treated with intravenous unfractionated heparin which necessitated them being treated as inpatients.

Low molecular weight heparin (LMWH) has revolutionised the treatment of patients with DVT as most are licensed for the treatment of DVT as a once daily dose.

Studies comparing LMWH and unfractionated heparin1-3 and the outpatient treatment of DVT patients with LMWH4,5 have demonstrated that the outpatient treatment with LMWH is safe, feasible and effective and is associated with a high degree of patient satisfaction.6

Many hospitals in the UK now have nurse-led outpatient treatment service for patients with uncomplicated DVT. However, such a service is a new to Ireland.

Deep venous thrombosis protocol

A protocol was developed by the A&E consultant for the management of DVT patients as outpatients with the agreement of the medical division in the hospital. A nurse was recruited to run the programme.

The protocol involves a medical assessment and examination of patients suspected of having a DVT using a Risk Probability Assessment (RPA) score developed by Wells et al.7,8

Patients are assessed and categorised as being at low (zero or less), moderate (one or two), or high (three or greater) risk probability for DVT by using the scoring model (see Table 1). There are nine significant variables. A patient receives a value of one for a positive variable and a minus two for the single negative variable (alternative diagnosis). The sum of the integer values  provides a score for each patient.

All patients with potential DVTs are referred to the DVT nurse to request a duplex scan and perform haematological investigations (D-dimers, full blood count and coagulation screen). If the duplex scan is negative, the guidelines in Table 2 are adhered to for discharge of patients.

Wells et al8 suggest that patients with negative scan results should have the non-invasive test repeated twice in seven days to detect extending calf-vein thrombosis, as duplex scan is less sensitive and specific in the calf veins.

This was included in an original protocol, however, the radiology department could not accommodate serial repeat ultrasounds and therefore the protocol was amended so patients return to the A&E review clinic to assess the need for repeat scans.

Patients with positive scans are referred to the medical team for management and assessment of suitability for outpatient treatment. Patients considered suitable are commenced on tinzaparin with the simultaneous administration of loading doses of warfarin.

Four days after commencing treatment patients return to the DVT nurse to obtain an international normalised ratio test. If the patient has reached a therapeutic range, tinzaparin is discontinued and warfarin continued. If not, the patient continues on both until they return to the medical consultants OPD within a week of diagnosis of DVT.

The fact that patients are always seen by the same nurse ensures continuity of care and consistency of information being given. During an extensive patient teaching session the nurse explains the details of their condition, the treatment involved and provides patients with a good understanding of anticoagulation therapy.  The patient or caregiver is taught to monitor for any adverse reactions and perform any other self-care measures deemed necessary to prevent complications.

The patient or caregiver must be aware that they may have adverse outcomes from progression of the clot and that outpatient treatment will not lessen the serious nature of venous thromboembolic disease.

If the patient or caregiver is willing to self-administer the tinzaparin, the nurse provides a step-by-step guide to self- injecting. Otherwise the public health nurse is contacted to give subsequent daily injections.

In addition to verbal advice, the DVT nurse provides a care package which contains preloaded syringes of tinzaparin, warfarin tablets, drug information sheets, DVT booklet, warfarin booklet, GP and PHN letters. Patients are also given the DVT nurses bleep number to enable them to contact her for advice if required.

Risk Probability Assessment RPA7,8
  Clinical feature Score
History  Paralysis/paresis plaster immobilisation of lower limbs +1
Bedridden for > 3 days 
Major Surgery < 4/52
Airline flight of > 4 hours in previous 5/52
+1
Active cancer treatment in previous 6/52 or palliative treatment +1
On admission Entire leg swollen +1
Calf swollen 3cm > other leg (measured 10cm below tibial tuberosity) +1
Tenderness along deep veins +1
Pitting oedema (worse in symptomatic leg) +1
Collateral superficial veins (non-varicose) +1
Alternative diagnosis more likely than DVT -2
Total High 3, Moderate 1-2, Low ? 0 
   
 
Guidelines for discharge of patients with negative first scans
  RPA D-dimer Action taken
First episode 3 N/A
  • Refer to the A&E review clinic
  • Appointment in two days
  • Commence therapeutic tinzaparin
0-2  > 0.5mg/l
  • Refer to the A&E review clinic
  • Appointment in two days
  • No tinzaparin
0-2 < 0.5mg/l
  • Discharge with advice sheet
Previous episode of DVT N/A > 0.5mg/l
  • Refer to the A&E review clinic
  • Appointment in two days
  • Commence therapeutic tinzaparin
N/A ? 0.5mg/l 
  • Refer to the A&E review clinic
  • Appointment in two days
  • No tinzaparin

Results

Over the first six month period during which the protocol became fully operational, 297 patients were referred to the service. Of these, 44 patients had positive scans, four patients were diagnosed as having DVTs on a second scan and one on a third scan.

Of  those patients with positive scans 22 were treated as outpatients and 22 were admitted due to either extension of thrombus to the IVC, high bleeding risk, IVDA, pregnancy or dementia.

All but one patient with positive scans had higher than normal d-dimers but this patient had a high RPA. Of the patients who were managed as outpatients one was admitted two months later from over warfarinisation and one presented two months later with shortness of breath and subsequently died (no autopsy was performed).

Reducing bed occupancy

The national bed crisis has necessitated that hospitals look inward and find ways of reducing bed occupancy. This Dublin teaching hospital has provided an excellent example of how this can be achieved by allowing the treatment of DVT patients as outpatients while also providing benefits to the patient. It also provides opportunities for nurses to expand their role in the care of patients with DVT.

The success of the programme depends on the protocol being rigidly adhered to. This must be co-ordinated with a multidisciplinary discharge programme, which includes structured nursing education with primary care and physician follow up.


Angela Kyne is acting CNM2 in A & E, Aidan Gleeson is a consultant in A & E Medicine and Barry Boland is an A & E Registratr, all at Beaumont Hospital

References are available from INO Library.

 

 


 


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