Seroma drainage following breast surgery (Guidelines)


A seroma is a collection of fluid, consisting of lymph and serous fluid, which often collects beneath the skin flaps after any form of breast surgery and in the dead space of the axilla following an axillary node clearance and beneath the skin flaps of the donor site for flap reconstruction.

Seroma fluid is initially collected in the drains post-operatively and typically begins to accumulate at the operation site following drain removal.  Some seroma formation is an expected consequence of surgery and not a sign of infection or indication of a post operative complication.  The site of the seroma is behind and around the surgical scar.

Obesity and challenging dissection are the main risk factors regarding high production of seroma fluid.   Besides a few established factors such as body mass index, early drain removal and use of low vacuum drains, consensus is lacking among studies regarding risk reduction of seroma with different groups producing conflicting evidence.

Percutaneous aspiration remains the only successful management of seroma. 

Aim/purpose of protocol

For clinically competent staff to

  1. Assess the need to drain the seroma.
  2. Safely drain the seroma

Patient group

Patients with a breast cancer diagnosis who have undergone mastectomy, axillary node clearance, or latissimus dorsi (LD) flap reconstruction (donor site only) may require proactive seroma drainage.

Indication for pro-active seroma drainage



The seroma is causing the skin to be tense

Seromas which are causing the skin to be tense are likely to be very uncomfortable and may interfere with the healing of the surgical scar.   

The seroma is causing pain or discomfort to the patient.
The seroma is causing a reduction in shoulder movement.

To aid patient comfort and promote postoperative mobility.

There are signs of infection at the surgical site (hot, very red).

If there are any signs of infection, seroma fluid should be drained and sent to microbiology for culture and sensitivity.
If there are obvious signs of systemic sepsis or pus is retrieved antibiotics should be considered as per soft tissue infection protocols.

*For patients who have an implant as part of their LD reconstruction, the clinician should liaise with the breast care team prior to seroma drainage.

Extra care should be taken in assessment and drainage due to the potential serious consequences if infection is introduced.

Contra-indications for pro-active seroma drainage



Seroma is present but estimated collection is below 70mls and/or causing no discomfort to the patient.

Previous seroma drainage yielded below 70mls seroma fluid.

Seroma is present but not causing pain or discomfort.

Draining small seromas which are not causing discomfort  is not clinically necessary and increases risk of infection as this is an invasive procedure. 

Similarly, prolonged drainage is troublesome as it increases the risk for infection and can significantly delay adjuvant therapy. 

Caution is advised in patients taking anticoagulants and a senior opinion may be required prior to seroma drainage.

Clinical Management

Staff training

Seroma assessment and drainage is considered to be an extended nursing practice. Staff will have been trained under supervision and agreed to be competent in seroma assessment and drainage before performing the procedure themselves.  A competency sheet is attached in Appendix 1.


Equipment required

  • Trolley or firm base
  • 20ml or 50ml syringe
  • 19 G winged infusion set (1.1 x 19 mm)
  • Disposable gloves / apron
  • Inco sheet or similar
  • Skin disinfectant wipe or device
  • Sharps box
  • Disposable bowl
  • Gauze / dressing tape
  • Small plaster



Assess patient

Ascertain ‘degree’ of seroma and if this indicates drainage 

Position patient comfortably usually in an upright sitting position on couch

Explain procedure to patient and obtain verbal consent

Prepare equipment

Wash hands

Minimise risk of infection

Clean and prepare trolley/ base for equipment

Ensure cleanliness is maintained.

Put on disposable gloves

Potential of  contamination by seroma fluid.

Prepare 20ml or 50 ml syringe and 19g winged infusion set

Large bore needle facilitates aspiration. Large syringe reduces disconnection required.

Cleanse patient skin using disinfection wipe and allow to dry

Achieve full topical cleanliness

Insert needle into central or lower aspect of the seroma

Gravity assists aspiration. Ensuring chest wall is not punctured

Aspirate seroma noting amount and type of fluid

Accurately record for progress

If seroma does not immediately aspirate – gently move needle within fluid

If aspiration is unsuccessful another puncture site can be used, maximum 3 attempts

Seromas can be loculated

Use new needle for each further attempt

Maintain cleanliness

When aspiration complete, apply gauze or cotton wool with slight pressure, then small plaster or dry dressing

To reduce seroma leakage from needle insertion site and maintain cleanliness

Ensure patient feels comfortable

Discuss need for next appointment

Encourage patient to contact Breast Care Nurses if they have any concerns or queries

Keep patient informed and reduce anxiety

Document in patient's nursing or medical notes

Maintain accurate records, assist accuracy when communicating with colleagues

Risk Management


It is essential to observe the colour of the fluid drained. If the specimen is cloudy, or the skin looks erythematous/cellulitc prior to drainage, send a specimen for culture and sensitivity and notify the breast care nurses. The patient may require antibiotics.

Accidental needle damage to pleura

If the patient experiences any difficulty in breathing during or immediately after seroma drainage a senior review should be sought immediately, as a CXR and medical treatment may be required.

Factors associated with seroma drainage:

Administrative factors

Clinician inexperienced in the drainage of seromas.

Clinicians will receive sufficient competency based training in seroma drainage in patients who have undergone surgery for breast cancer (as detailed in Appendix 1).

Consent not obtained

Clinician to check that informed verbal consent has been obtained.

Environment conducive to the drainage of seromas.

Appropriate privacy available for the drainage of seromas.

Treatment delivery factors

Accidental needle damage to pleura

Patient to inform breast unit, GP or out of hours service if experiencing any breathing difficulties

Risk of infection

Assess wound for signs of inflammation, discuss with breast unit if appropriate

Inappropriate preparation of clean field

Clean technique to be used in the drainage of seromas to minimise risk of infection

Psychosocial  factors

Patient appears  anxious or depressed

Signpost to appropriate area of care, such as Maggies/ Macmillan CNS/Breast Care Nurses/ peer support group

After care

  1. The patient can remove the plaster or dressing later that day.
  2. The clinician will make the patient a further appointment for aspiration of seroma if required, or advise the patient of signs/symptoms which would prompt contact for further seroma assessment
  3. The amount and type of fluid will be recorded in the patients notes and contact made with the breast care nurses if any sign of infection or difficulty with aspiration.
  4. The patient should be advised that if she/he experiences any difficulty in breathing after seroma drainage they should contact the emergency department as a chest x-ray and medical treatment may be required.


Dougherty L, Lister S (2015) The Royal Marsden Manual of Clinical Nursing Procedures (Ninth Edition) pp 853.  Wiley Blackwell, West Sussex.

Keogh G, Dalty J, McCardle C, Cook T (1998) Seroma formation related to electrocautery in breast surgery.  Breast Journal  7 pp 39 – 41.

Srivastava V, Basu S, Shukla V K (2012) Seroma Formation after Breast Cancer Surgery:  what we have learned in the last two decades.  Journal of Breast Cancer 15 (4) pp 376 – 380

Last reviewed: 01/12/2021

Next review date: 01/12/2024

Author(s): General Surgery.

Approved By: TAM subgroup of ADTC

Reviewer name(s): Consultant Breast & Oncoplastic Surgeon.

Document Id: TAM434