Understanding the patient’s condition before inserting a medical device is a vital step in ensuring safe and effective care. This involves a thorough assessment to determine suitability and identify any potential risks. Equally important is recognising the factors that could lead to complications during or after the procedure, allowing for proactive measures to be taken and improving overall outcomes.
Pre-procedure patient evaluation
Before inserting a central venous catheter, obtaining a thorough patient history is essential. This will directly influence device selection, insertion, site choice, and overall safety. Understanding the patient’s general health, comorbidities, full blood count, and vascular access history provides a clearer picture of potential risks and helps prevent complications.
A key part of this assessment is reviewing previous long‑term or repeated vascular access. Prior lines may have altered the patient’s venous anatomy, increased the risk of stenosis or thrombosis, or resulted in complications that should guide future decisions.
Before insertion, clinicians should gather information on:
- Previous devices used – Identifying whether the patient has had PICCs, CVCs, ports or dialysis catheters helps determine which vessels could already be compromised. This prevents repeated cannulation of a vein that may be narrowed or damaged, maintaining long‑term vascular health.
- Any complications associated with those devices – A history of catheter‑related bloodstream infection, thrombosis, occlusion or malposition alerts the clinician to potential risks during a new insertion. This may lead to choosing an antimicrobial or antibiotic‑impregnated catheter, altering the insertion site, or involving a more experienced operator.
- Previous insertion sites – Knowing where previous catheters were placed helps avoid overusing one anatomical area. Recurrent use of the same vein increases the likelihood of stenosis or scarring. Documentation of successful or difficult sites guides a more informed choice and can reduce procedural time and patient discomfort.
- Reason for removal – If the prior catheter was removed because of infection, malfunction or intolerance, similar problems may occur again. This information steers decisions on catheter type, number of lumens, material and the need for antimicrobial protection.
Why This Matters
Each element of the patient’s access history influences the immediate plan and protects their future venous access options. A well‑informed approach reduces the risk of avoidable complications, supports better line longevity, and ensures that clinicians select the most suitable catheter for the patient’s clinical needs.
Laboratory Assessment
Before device placement, a laboratory assessment is useful to identify any factors that may increase the risk of complications, for example, consider coagulation factors and treat appropriately before inserting a CVC.
Consent
Consent is a critical component of ethical practice. Written informed consent must be obtained for all invasive procedures, ensuring patients understand the risks, benefits, and alternatives[1].
Every adult must be presumed to have the mental capacity to consent or refuse treatment, unless they are unable to: take in or retain information, understand the information provided, or weigh up the information as part of the decision-making process. Nurses and midwives have three over-riding professional responsibilities with regard to obtaining consent (NMC, 2015): ensuring that the care of people is their first priority and they gain consent before beginning and treatment or care; that the process of establishing consent is rigorous, transparent and demonstrates a clear level of professional accountability; and that all discussions and decisions relating to consent are recorded.
Practitioners must also be aware of variations in consent laws across the UK and adhere to local and national guidelines. For example, in Scotland, The Adults with Incapacity Act 2000, provides ways to help safeguard the welfare and finances of people who lack capacity, protecting adults (people aged 16 or over) who lack capacity to take some or all decisions for themselves, including those with inability to communicate a decision, allowing a relative, friend or partner to make decisions on their behalf[2].
Pain Management
In addition to understanding the patient’s history and gaining their informed consent, it is important to consider their comfort during the procedure.
Studies have shown that adequate patient assessment can lead to more effective pain control and fewer post-operative complications. The pain receptors of the skin and other tissues are all free nerve endings. There are pain receptors throughout the superficial layers of the skin as well as in some tissues (arterial walls and joint surfaces). The skin is therefore a very sensitive organ as at any single point on its surface there could be at least three different networks of nerve fibres running across it[3].
Pain signals can be fast and sharp or slow and chronic.
- Fast and sharp – Transmitted by either thermal or mechanical pain stimuli and transmitted in the peripheral nerves to the spinal cord by small type Aδ fibres.
- Slow and chronic – Transmitted mainly by chemical pain stimuli but can be caused by persistent mechanical or thermal stimuli. It is transmitted by C fibres[4].
To minimise any discomfort and pain during CVC insertion, there are two main techniques, using local anaesthesia and providing psychological support to the patient, which when used together, can help to effectively reduce the pain of CVC insertion. This discomfort is typically felt as a significant amount of pressure for example, when vessel dilators are used.
Local anaesthesia provides an effective, economical and rapid pain relief for this procedure direct to the site of cannulation and is administered immediately prior to the procedure. Lidocaine is the most commonly used injectable local anaesthetic and comes in different concentrations (.05%, 1% and 2%).
It is also important to consider the potential risks of administering local anaesthesia, which include; allergic reactions, anaphylaxis, inadvertent injection into the vascular system, and obliteration of the vein[5].
In addition, using diversion strategies, for example, breathing techniques throughout the insertion, can also be an effective method (when used in conjunction with anaesthesia), to help the patient relax as it can lessen the awareness of pain or discomfort. It is important therefore to ensure the patient receives necessary top ups of anaesthesia and adequate psychological support[6].
Additional Considerations
Some additional considerations when assessing the patient are:
- Clinical status: Most patients will be in a stable condition, but acute illness increases complication risk[7].
- Allergies: Systematic and topical allergies appear to be increasing. In relation to CVC insertion, this could be related to chlorhexidine. This is becoming an increasing issue with reports of anaphylaxis[8]. Patients may also display allergies to dressings, latex etc. Allergies can range from a skin rash through to full anaphylaxis. Appropriate medical advice should be sought if an allergy does occur and this should be reported, highlighted and documented.
- General physical assessment: Respiratory, cardiovascular, neurological, muscular–skeletal and vascular assessment as issues related to these systems can have an impact on the successful placement and function of a CVC
- Patient cooperation: Confusion or lack of cooperation can complicate the procedure.
Conclusion
A thorough pre-procedure evaluation is essential for the safe and effective insertion of a central venous catheter. By carefully reviewing the patient’s medical history, previous device use, and laboratory results, clinicians can anticipate and mitigate potential risks. Additional factors such as allergies, clinical stability, and patient cooperation must also be considered to ensure optimal outcomes. This comprehensive approach supports informed decision-making and enhances patient safety throughout the procedure.
Continue Reading
- Article 1: Understanding CVCs: Roles, Anatomy, and Device Selection
- Article 2: Preparing for CVC Insertion – Patient Assessment, Consent and Pain Management
- Article 3: Infection Prevention and Aseptic Techniques
- Article 4: Foundations of Ultrasound Physics and Applications
- Article 5: Central Venous Lines – Insertion Techniques and Pain Management
- Article 6: Navigating Complications in Central Venous Access
- Article 7: Post-Insertion Care, Maintenance and Safe Removal
References
[1] Department of Health. Reference Guide to Consent for Examination or Treatment. 2009.
[2] Adults with Incapacity (Scotland) Act. 2000.
[3] Nathan, P (1988) The Nervous System. 3rd edition. Oxford University Press. Oxford
[4] Guyton, AC, Hall, JE (2006) Textbook of Medical Physiology. 11th Edition. Elsevier Saunders. Philadelphia.
[5] Weinstein SM. Plumer’s Principles & Practice of Intravenous Therapy. 8th ed. Philadelphia: Lippincott Williams & Wilkins; 2007.
[6] Hamilton, H: in Hamilton and Bodenham (2009) Central Venous Catheters. Wiley – Blackwell. UK
Hart. S (2007) Using an aseptic technique to reduce the risk of infection. Nursing Standard 21 (47) 43 – 48
[7] Hamilton, H: in Hamilton and Bodenham (2009) Central Venous Catheters. Wiley – Blackwell. UK
[8] Weng, M., Zhu, M., Chen, W., & Miao, C. (2014). Life‑threatening anaphylactic shock due to chlorhexidine on the central venous catheter: a case series. International Journal of Clinical and Experimental Medicine, 7(12), 5930–5936.
