Pre-Op Assessment — Patient Preparation Guide for Student Nurses

Why pre-op assessment matters

Pre-operative assessment is the systematic process of evaluating a patient's fitness for surgery and anaesthesia before they enter the operating theatre. It has two equally important goals: identifying clinical risk factors that could make surgery unsafe, and ensuring everything is in place to proceed without avoidable delays or cancellations.

In NHS and HSE hospitals, theatre cancellations cost an estimated £700–£1,000 per case and cause significant distress to patients who have often fasted, taken time off work, and mentally prepared for a procedure. The majority of preventable cancellations trace back to gaps in pre-operative assessment — missing consent, unreported allergies, an abnormal investigation result that wasn't acted on, or a patient who arrived having eaten breakfast on a nil-by-mouth list.

Pre-operative assessment is typically completed in a dedicated pre-assessment clinic days or weeks before admission, and then verified again on the ward on the day of surgery. As a student nurse, you will most commonly be involved in the day-of-surgery checks — confirming, documenting, and preparing, not initiating assessments from scratch.

Systematic pre-op assessment checklist

A thorough pre-op assessment covers seven domains. Work through them in order — skipping around under time pressure is how things get missed.

1. Airway

The anaesthetist performs the formal airway assessment, but nursing staff should flag anything unusual. Ask about previous anaesthetic problems — difficult intubation, awareness under anaesthesia, or post-operative nausea and vomiting (PONV). Check the pre-assessment records for a Mallampati score or any documented airway concerns. If a patient mentions they were told they had a "difficult airway" after a previous procedure, escalate immediately — this must be documented and communicated to the theatre team before induction.

2. Allergies

Confirm all known allergies and the nature of the reaction — not just "penicillin" but "penicillin causes anaphylaxis with throat swelling." Document precisely in the notes and on the allergy wristband. Common surgical allergies to confirm include: antibiotics (particularly penicillin and cephalosporins), latex, iodine/Betadine, chlorhexidine (used in skin prep and central lines), and contrast media. A patient with a latex allergy requires a latex-free theatre — flag this early so theatre staff can prepare.

3. Medications

Review the medication administration record (MAR) and reconcile against the pre-assessment drug history. Key decisions include:

• Anticoagulants (warfarin, DOACs, LMWH): Must be withheld according to the surgical bridging protocol. Confirm this has happened and document in the notes.
• Antiplatelets (aspirin, clopidogrel): Usually withheld 5–7 days pre-surgery for elective cases; confirm with the surgical team for emergency cases.
• Diabetes medications: Insulin and metformin protocols vary by trust — check the variable-rate insulin infusion (VRII) plan is in place if relevant.
• Antihypertensives: Most are continued, but ACE inhibitors and ARBs may be withheld on the morning of surgery — check the surgical team's instructions.
• Steroids: Patients on long-term steroids require peri-operative steroid cover to prevent adrenal crisis.

4. Fasting status (nil by mouth)

NICE guidelines and the Association of Anaesthetists of Great Britain and Ireland (AAGBI) specify the following minimum fasting times before elective surgery under general or regional anaesthesia:

Confirm fasting times directly with the patient — do not rely solely on the chart. Ask: "Have you had anything to eat or drink since midnight?" and document the time and what was consumed. If a patient admits to eating outside their fasting window, inform your mentor immediately — the case may need to be postponed.

5. Consent

Valid consent for surgery must be in the notes before the patient leaves the ward. Check that the consent form is signed by both the patient and the operating surgeon (or a delegated doctor who has sufficient knowledge of the procedure). Confirm the patient understands: the nature of the procedure, intended benefits, material risks, and alternatives. Consent can be withdrawn at any time — if a patient expresses doubt or asks to cancel, pause everything and escalate to the surgical team. Never pressure a patient to proceed.

6. Patient identification

Identity errors in theatre are never-events. Before any patient leaves the ward, confirm: full name and date of birth verbally (ask the patient to tell you, not just confirm "yes"), NHS/hospital number on the wristband matches the notes, the wristband is intact and legible, and allergy wristband is in place if applicable. Two-point identification is the minimum — some trusts require three-point (name, DOB, NHS number).

7. Site marking

For any procedure involving a laterality decision (left vs right knee, left vs right hand, correct level of spine), the operating site must be marked with a permanent marker by the operating surgeon before the patient leaves the ward. As a student nurse, your role is to verify the mark is present and corresponds to the consent form and operation notes. If a laterality procedure is on the list and there is no site mark, do not send the patient to theatre — escalate immediately.

WHO Surgical Safety Checklist — your role

The World Health Organization Surgical Safety Checklist was introduced in 2008 and has been shown to reduce surgical mortality and complication rates by over 30%. It is now mandated in all UK and Irish hospitals. The checklist has three phases: Sign In (before anaesthesia), Time Out (before incision), and Sign Out (before the patient leaves theatre).

Sign In (before anaesthesia induction — theatre)

Conducted by the anaesthetic nurse and anaesthetist. Confirms patient identity, operative site, consent, allergies, airway risk, aspiration risk, and whether blood loss is anticipated. As a ward nurse accompanying the patient, you may be present for this.

Time Out (before skin incision — theatre)

The entire team pauses. Surgeon, anaesthetist, and scrub nurse verbally confirm: patient name and procedure, antibiotic prophylaxis has been given (within 60 minutes of incision), anticipated critical steps, imaging available, and whether any team member has concerns. This is a genuine safety stop, not a formality.

Sign Out (before patient leaves theatre)

Confirms: procedure name, instruments and swabs counted, specimens labelled, equipment issues to report, and post-operative recovery plan.

Antibiotic prophylaxis

Surgical antibiotic prophylaxis reduces surgical site infection (SSI) rates. NICE guidelines (NG125) specify antibiotic choice, dose, and timing. The key rule: prophylaxis must be given within 60 minutes of skin incision. On most wards, this is prescribed to be administered at anaesthetic induction — confirm with your mentor whether the ward or theatre is responsible for administration, and document the timing clearly on the MAR.

Pre-op investigations: bloods, ECG, and CXR

Not every patient needs every investigation. NICE guideline NG45 (Routine preoperative tests for elective surgery, 2016) provides evidence-based guidance on which tests are indicated based on the ASA grade, type of surgery (minor, intermediate, major), and patient comorbidities. Over-investigation wastes resources; under-investigation misses risk.

Blood tests

On the day of surgery, confirm results are available and reviewed. Escalate any abnormal values to the surgical team before sending the patient to theatre. A potassium of 2.8 mmol/L or a haemoglobin of 65 g/L in a patient about to undergo bowel resection needs urgent attention — not a note in the handover for the next shift.

ECG (12-lead Electrocardiogram)

Indicated for patients aged 65+, known or suspected cardiac disease, significant hypertension, or major/complex surgery. The ECG is reviewed by the anaesthetist pre-operatively to identify rhythm abnormalities, conduction defects, ischaemic changes, or evidence of a recent myocardial infarction. As a student nurse, your role is to confirm the ECG has been done, is in the notes, and is labelled with the correct patient details and date. An undated ECG is as problematic as no ECG — the clinical picture must be current.

Chest X-Ray (CXR)

NICE NG45 does not routinely recommend CXR for pre-operative assessment unless there is a specific clinical indication: known or suspected cardiac failure, significant respiratory disease, recent emigration from a country with high tuberculosis prevalence, or major thoracic surgery. A CXR ordered purely because the patient is over 60 is no longer best practice. Confirm whether one has been ordered and reviewed — and if the anaesthetist has any concerns about the film, flag these to the surgical team before the patient is sent to theatre.

Patient preparation before theatre

Physical preparation happens in the final 1–2 hours before the porter arrives. Work through each step methodically — rushing or delegating without checking is how items get missed.

Handing over to theatre staff using ISBAR

When the porter and theatre nurse arrive to collect your patient, the ward-to-theatre handover is one of the highest-risk transitions in surgical care. Communication failures at this point lead to omitted information, delays, and in rare cases serious harm. The ISBAR framework structures this handover so nothing critical is missed.

ISBAR for pre-operative handover

The theatre nurse receiving the patient should confirm they have received and understood the handover. If they ask questions you can't answer, get the information before the patient leaves — do not say "it's all in the notes" and wave them off. The handover is an active communication, not a document transfer.

What to do after the patient leaves

Document the time of transfer to theatre in the patient's notes. Ensure the bed space is ready for post-operative return: suction available and functional, oxygen flow meter checked, IV stand in place, post-op observation chart at the bedside, call bell within reach. If the patient is expected to return with a drain, catheter, or specific monitoring requirements, ensure the relevant equipment and documentation is prepared before they arrive back from recovery.

For guidance on what to monitor once your patient returns from theatre, see our guide to post-op observations.