Please click on the tables and figures to enlarge

Cannulation conundrums: what help is available?

A. Gupta*¹, BDS, PG Cert, MFDS RCSPG
T. Nagpal², BDS, PG Cert, PG Dip, MFDS RCSEd
¹Oral Surgery Registrar, Southend Hospital, Prittlewell Chase, Southend-On-Sea, SS0 0RY
²Oral Surgery Registrar, Luton and Dunstable Hospital, Luton, LU4 0DZ
*Correspondence to: Ashana Gupta
Email: Ashana.Gupta2@nhs.net
Gupta A, Nagpal T. Cannulation conundrums: what help is available?. SAAD Dig. 2024: 40(II): 117-123

Abstract

A fundamental requirement of intravenous sedation is access. Successful cannulation is vital for delivery of the sedative, reversal agents and for management of medical emergencies. Experienced clinicians, however, will be able to recall occasions where they have struggled to gain intravenous access.

Pre-operatively, the consultation visit can be utilised to prepare the patient for sedation cannulation. Patients can be advised on hydration to improve vein visibility at the time of cannulation. The clinician can also visualise blood vessels that would be suitable for cannulation at the initial assessment. Application of the Adult Difficult Intravenous Access Scale to grade cannulation difficulty is useful for record keeping as well as preparing the clinician for cannulation difficulties and organising appropriate adjuncts. At the time of cannulation, tapping of the vein, placement of warm compresses, milking of veins proximally to distally and application of a tourniquet can increase venous prominence. Adjuncts that can be used include the sphygmomanometer cuff at or below diastolic pressure, transillumination and topical venodilation with nitroglycerine ointment. The availability of portable handheld ultrasound devices has also enabled ultrasound guided cannulation within a dental setting.

This paper provides an algorithm to guide the clinician when managing difficult cannulation.

Introduction

Intravenous (IV) cannula placement is required to administer sedative medication as well as reversal agents. This is often the first clinical stage of delivering conscious sedation, with the exception being those that must be given a form of premedication or alternative sedation technique to aid the acceptance of IV cannulation. It can be argued that being prepared with the full adjunctive armamentarium for successful IV access is crucial as the gold standard for delivery of the sedation reversal agents is through intravenous administration.

Cannulation can be considered a challenging skill with a cross-sectional survey conducted in 25 countries stating a potential failure rate between 31% and 67%.¹ Repeated attempts at cannulation can pose a burden to both the patient and healthcare system. Risks associated with repeated cannulation include pain, infection, nerve damage, bleeding, haematoma, air embolism and occlusion.^2,3

The average duration for ‘time taken to cannulate’ varies between 32 seconds and two minutes in successful cases of venous access. When access is difficult, reports indicate the time taken can increase to be between 66 seconds and five minutes.⁴

The Welsh peripheral intravenous cannulation best practice guidelines suggest a maximum of two failed cannulation attempts. Clinical judgement should be exercised and reassessment with senior support, or cannulation adjuncts may be needed.⁵ This paper aims to inform clinicians of their options to aid adult cannulation and ultimately ensure they are able to gain venous access as efficiently as possible, overcoming arguably the most crucial step to be able to deliver successful conscious sedation.

Pre-operative patient assessment

Venous access should be assessed during the patient’s consultation visit when treatment planning sedation. Consideration of the patient’s medical history is essential as this may complicate cannulation. Relative contraindications for insertion of a peripheral cannula at a particular site may include phlebitis, sclerosed veins, burns, history of trauma, obesity, ipsilateral mastectomy and lymph node dissection.² Awareness of these factors will enable the sedationist to prepare and choose an appropriate venous access site. Swift cannulation and administration of sedation drugs is an important step in managing the anxious patient.

As part of the consent process, patients should be made aware of the need for cannula insertion, potential insertion sites, the associated risks and potential complications.^6,7

The National Institute for Health and Care Excellence (NICE) recommends that clinicians make a clinical decision regarding the ideal site and choice of vein before cannulating, to reduce the risk of cannula failure and complications.⁸ Sites to be avoided include any veins in proximity to arteries, superficial or sclerosed veins. If the patient is postmastectomy in breast cancer treatment, the side associated with breast surgery is best avoided due to the risk of lymphoedema developing post node removal.⁵

The cephalic or basilic vein on the forearm (Figure 1A), cephalic vein of the wrist and the dorsal metacarpal veins on the back of the hand (Figure 1B) are considered best practice for cannulation.⁷

Predicting difficult venous access

Cannulation can fail for several reasons. These can be categorised to systemic patient factors, local patient factors or clinician factors as shown in Table 1.

Systemic factors

Patients assessed to be American Society of Anaesthesiologists (ASA) I and ASA II are appropriate for management in a primary dental care setting for conscious sedation, those who are considered ASA III should be referred to secondary or tertiary settings and are likely to have more difficult venous access due to a combination of the above factors.

To mitigate some of the preventable factors, appropriate pre-operative instructions should be given to patients attending for sedation to maximise the chances of successful cannulation. Fasting prior to dental conscious sedation is an often-discussed issue. As loss of airway reflexes should never occur in conscious sedation in dentistry, fasting is unnecessary.^10,11 Eating and drinking appropriately allows patients to minimise the risk of dehydration prior to attending and increases the visibility of their veins. Secondary or tertiary care settings may have fasting instructions which may contrast with this due to the use of polypharmacy and broad hospital policies also covering our anaesthetic and gastroenterology colleagues and their procedures under conscious sedation.

Local factors

The Adult Difficult Intravenous Access Scale (A-DIVA) is a recently created predictive scale to identify patients with difficult intravenous access. This additive A-DIVA scale predicts the likelihood of a difficult intravenous access in adult patients prospectively, based on clinical observations and five variables (Table 2).¹²

Each variable is assigned a binary score of zero or one based on ‘yes’ or ‘no’ responses. A score of zero to one can be considered low risk for cannulation difficulty. A score of two to three is considered medium risk and a score of four and above can be considered high risk for cannulation difficulty. Applying the A-DIVA scale to surgical patients is a quick aid for the clinician; increasing confidence in successfully inserting a peripheral intravenous catheter on the first attempt and / or preparing the clinician to anticipate difficulty and to organise adjunctive techniques, such as ultrasound, pre-emptively.¹³

The Difficult Intravenous Access Scale (DIVA) can also be applied to predicting cannulation difficulty in children. It consists of a four-point scale and accounts for age, a history of premature birth, skin shade, vein visibility and vein palpability.¹²

A limitation is that the scale was developed by anaesthetists for use in general anaesthetic and Accident and Emergency departments.¹² The principles of decision making, however, can be applied to intravenous sedation in the elective dental scenario but with caution due to the difference in intended application.

Clinician factors

Operator experience is a significant factor in successful cannulation.¹⁴ In some instances, improved technique can overcome difficulties in cannulation. This article discusses cannulation failures and adjuncts for the experienced clinician which can be utilised when difficult intravenous access is predicted.

Signs of failed cannulation are:¹⁵

• Tissuing / extravasation. This occurs if the cannula is inserted beyond the vein. Tissuing can be avoided if the cannula is introduced to the vein at an angle of 15° by the operator
• Haematoma formation. This should be managed by applying a firm pressure dressing and locating an alternative distant site for cannulation
• Intra-arterial cannula insertion. This is at higher risk of occurring when cannulating the dorsum of the hand.

Cannulation complications include:

• Thrombophlebitis: an inflamed vein which can occur due to mechanical trauma from cannulation techniques or cannulating over an area of flexion. It is recognised as hardening of the tissue at the cannulation site, pain and erythema¹⁵
• Nerve damage: the median nerves and radial nerves are at most risk during cannulation of the basilic or cephalic vein at the antecubital fossa¹⁶
• Unintended arterial cannulation can occur and clinicians should be aware of recognising these signs. Pulsatile bright red blood backflow into the cannula, pain on insertion or blanching at a site distal to cannulation can all be indications. Failure to recognise arterial cannulation and delivery of sedative drugs can lead to severe tissue damage and result in compartment syndrome.¹⁵

Adjunctive techniques to aid cannulation

Tourniquet use

The first use of a tourniquet was recorded by Sushruta in 600BC, with use of leather to stop arterial bleeding.¹⁷ Within the context of cannulation, the effect of a tourniquet can be achieved by a commercially available wraparound tourniquet devices or by manual compression from an assistant 10 cm to 15 cm from the desired cannulation site. The aim is temporarily to block the venous outflow from the site whilst still allowing enough arterial inflow into the area. This causes a build-up of blood in the veins distal to the tourniquet. The vein therefore becomes temporarily dilated, palpable and easier to access. Another advantage of the tourniquet is that the access vein becomes anchored and is less mobile. It is important to be swift in cannulating as the tourniquet should be removed soon after. Prolonged application can lead to fragility of the vein.¹⁸ Once a tourniquet is applied, the patient can then be asked to place the limb downwards towards the ground below the level of the heart so gravity allows venous pooling thus increasing vein prominence. 

Sphygmomanometer cuff

An alternative to the torniquet technique is the use of a manual blood pressure machine cuff. The cuff can be placed above the venous access site and inflation pressure set to the patient’s diastolic pressure or just below it, once again, to ensure the appropriate restriction of venous outflow whilst maintaining arterial inflow. This technique may be more successful due to a more accurate control of outflow occlusion; also known as venous stasis.¹⁹

Percussion of the vein

The vein should be palpated by the clinician to determine the relative size of the vessel and the direction in which it runs. If the vein is not obvious, the clinician may gently tap the skin directly overlying the vein. If the tapping is too firm, however, pain may cause reflex vasoconstriction. Alternatively, milking the vein proximally to distally may also increase venous palpability.¹⁸ Asking the patient to clench their fist whilst palpating the vein can also help to increase its prominence.  

Heat therapy

The application of a warm compress or immersing the venous access site in a warm water bath for two to three minutes will help to increase local blood flow and increase venous distension.¹⁸ Within a primary care dental setting, heaters used for composite capsules could be used to heat a compress, taking care to avoid heat related trauma. 

Transillumination

Transilluminating devices use near infrared light-emitting diodes (NIR-LED). The image is created due to the presence of deoxyhaemoglobin in venous blood which absorbs the red infrared light and illuminates the veins as dark lines on the skin surface. This gives the clinician a visual aid to determine where to palpate for veins.²⁰

Non-invasive vein illumination devices, eg AccuVein AV400 device, have been advocated for use in venepuncture or cannulation within the National Health Service (NHS) by NICE. The device can be used by any healthcare professional trained in intravenous cannulation including nurses and surgeons. The distributor provides initial training and education in using the device. Research has shown that vein finder devices reduce the rate at which the insertion site needs re-palpating after skin cleansing²¹ and can significantly increase intravenous access success rates with a 26% success rate at cannulation compared to only 19% success rate with visualisation or palpation of the vein.⁹

The device has an NHS acquisition cost of £3,300 + VAT and there may be additional costs for hands-free elements. Previous studies argued that poor vein visibility can make IV cannulation a challenge in children with dark skin colour even with the use of near infrared vascular imaging devices.²²

Venodilatation drugs

Topical ointments may be utilised to achieve venodilatation and increase blood flow. Nitroglycerin is broken down into nitric oxide. This causes relaxation of the smooth muscle of the blood vessel, causing increased blood flow. Application of 2% to 4% nitroglycerin ointment for at least two to three minutes applied over half an inch spread of skin can provide sufficient venous distension and equates to a dose of 7.5 mg nitroglycerin. Research shows fewer attempts at cannulation were required in subjects that had an application of nitroglycerin ointment when compared to the control group.²³ The United States Food and Drug Administration (FDA) also provide some guidance on the use of nitroglycerin transdermal ointment and recommend that heart rate and blood pressure should be monitored throughout.²⁴

Ultrasound guidance

Ultrasound +/- doppler should be considered if the vessel cannot be seen directly or palpated, viewed with a transillumination device or peripheral venous cannulation is considered to be difficult. This is based on the recommendation by the Association of Anaesthetists of Great Britain and Ireland.²⁵ The ultrasound can also be used to view nearby anatomy that must be avoided during cannulation, for example, the radial nerve that is close to the cephalic vein in the forearm (Figure 1A). 

Research shows a 10% higher initial and second attempt success rate when ultrasound guidance was used for vein localisation compared to conventional palpation techniques. Ultrasound guided cannulation shows promising results in most studies. Researchers cannulating the basilic and brachial vein under ultrasound guidance reported a 91% success rate. Complications were limited to paraesthesia in one percent of cases.^26,27

Two main types of ultrasound techniques can be used for cannulation. This includes audio guided doppler ultrasound which is not widely utilised. The most commonly used technique is the two-dimensional ultrasound scan that provides grey scale images of the anatomy.

The equipment recommended for intravenous cannulation under ultrasound guidance includes:

• An ultrasound machine with 7.5MHz or higher frequency
• A linear array probe also known as transducer
• A sterile lubricating gel.

The cost of the portable ultrasound machines is between £7,000 and £15,000.

For cannulation guidance, the transverse and cross-sectional view give the best view of the orientation of veins and arteries in relation to each other. Longitudinal views can be used to view the needle within the vein to ensure accurate intraluminal placement.²⁸

Ultrasound scanning use and interpretation require the clinician to undergo further training but key features to look for include linear grey or black shadows beneath the skin surface. Compression will cause the shadow to disappear if it is a vein as the lumen closes on compression whereas an artery lumen will remain open. The cannula can be guided into the vein in real time using the ultrasound scanner to visualise and ensure the needle tip remains in the vein.²⁵ Within secondary services, clinicians may be able to familiarise themselves with this technique by working alongside anaesthetists, consultants in Accident and Emergency departments and radiologists where this technology is more commonly used.

Alternative access site

It should be noted that peripheral venous access in intravenous drug misuse can be complicated by fibrosis of the veins from repeated cannulation attempts. In such cases, identifying suitable veins for venous access can be extremely challenging. Alternative venous access sites can be located in the foot, leg and include the deep brachial vein in the arm, however these should only be attempted in a secondary care setting by experienced clinicians. Complete, valid and informed consent must be obtained from the patient to cannulate difficult access sites.

For reference, Figure 2 demonstrates some of the alternative venous access points; such as the lesser saphenous and great saphenous vein in the foot (Figure 2A) and the external jugular vein in the neck (Figure 2B). 

Nitrous oxide inhalation

Needle phobia is a barrier for cannulation. There is a greater degree of peripheral vasoconstriction in response to acute mental stress.²⁹ Nitrous oxide inhalation sedation has been shown to reduce anxiety levels³⁰ and is a well-known vasodilator.³¹ Therefore it is an excellent facilitator of cannulation for needle-phobic patients that do not have a clearly accessible vein.

Decision-making algorithm for sedationists

There are a variety of methods which can be utilised to improve peripheral venous access. The resources available may differ depending on the setting in which the sedation is being provided. The following decision-making algorithm (Figure 3) may be applied to aid the clinician’s approach. 

Initial recognition of difficult venous access from the outset is crucial to limiting any distress to patients and clinicians and to reducing the incidence of multiple failed attempts at cannulation. By applying the access algorithm (Figure 3), early identification of factors which may make intravenous access more difficult is clearer and informed decision-making to aid venepuncture is therefore possible. Whilst the guidance suggests a maximum of two attempts, clinical judgement is required as to whether further attempts with improved technique is in the patient’s best interests. Using adjunctive measures may lengthen the time taken to cannulate, but is likely to reduce the number of attempts required to cannulate. 

Maximising clinical technique to cannulate

In the author’s experience, techniques that can improve cannulation success include pulling the skin overlying the venous access site with the supporting hand in order to stabilise the vein and to avoid snagging the skin with needle entry. If the needle bevel is found to be in contact with the vein wall, this can cause leakage of the sedative into the tissue fluid. This can be corrected by gently pulling the skin, this will separate the bevel from the vein wall.

The clinician must be willing to undertake further training to use adjuncts such as ultrasonography and ensure a steady flow of cases in order to maintain the relevant level of skill. To build confidence, clinicians can use ultrasound assistance for low-risk access points in order to increase familiarity. This practice is acceptable so long as it is not detrimental to the patient’s care and would not compromise any outcome. The current level of resources tailored specifically to those performing conscious sedation in a dental care setting is limited. There is scope for a course to be designed that can would incorporate these techniques. There is most definitely an opportunity for charities to create educational resources in this field.

Conclusion

Clinicians are encouraged to provide sedation assessment for patients at the consultation visit. Consultations for intravenous sedation should include assessment and appraisal of possibly difficult venous access in both primary and secondary care settings. The A-DIVA scale can help to grade and quantify the venous access difficulty and usage of the algorithm (Figure 3) may serve as an aide memoire for selecting the appropriate adjuncts to cannulation.

Declarations

There are no conflicts of interest.

References

1. Cooke M, Ullman A J, Ray-Barruel G, Wallis M, Corley A, Rickard C M. Not ‘just’ an intravenous line: Consumer perspectives on peripheral intravenous cannulation (PIVC). An international cross-sectional survey of 25 countries. PloS One 2018; 13: 1-18.

2. Helm R E, Klausner J D, Klemperer J D, Flint L M, Huang E. Accepted but unacceptable: Peripheral IV catheter failure. J. Infus. Nurs 2015; 38: 189–203.

3. Peripheral Intravenous Cannulation (PIVC) Insertion, Care and Removal (Adults). Sydney: South Eastern Sydney Local Health District, 2021.

4. Jacobson A F, Winslow E H. Variables influencing intravenous catheter insertion difficulty and failure: an analysis of 339 intravenous catheter insertions. Heart & Lung. J acute and critical care 2005, 34: 345–359.

5. Peripheral intravenous cannulation best practice guidelines issue 2.1. Wales: University health board, 2017.

6. Dougherty L. The Royal Marsden Hospital manual of clinical nursing procedures, 9th ed.. Chichester: John Wiley and Sons, 2015.

7. Thomas R K. Practical medical procedures at a glance. 1st ed. Chichester: John Wiley & Sons, 2015.

8. Intravenous fluid therapy in adults in hospital. London: National Institute for Health and Care Excellence, 2013.

9. Pan C T, Francisco M D, Yen C K, Wang S Y, Shiue Y L. Vein Pattern Locating Technology for Cannulation: A Review of the Low-Cost Vein Finder Prototypes Utilizing near Infrared (NIR) Light to Improve Peripheral Subcutaneous Vein Selection for Phlebotomy. Sensors (Basel) 2019; 19: 1-17.

10. Conscious Sedation in the Provision of Dental Care. London: Department of Health, 2003.

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13. Van Loon F H J, Puijn L A P M, Houterman S, Bouwman A R A. Development of the A-DIVA Scale: A Clinical Predictive Scale to Identify Difficult Intravenous Access in Adult Patients Based on Clinical Observations. Med 2016; 95: 1-8.

14. Rippey J C, Carr P J, Cooke M, Higgins N, and Rickard C M. Predicting and preventing peripheral intravenous cannula insertion failure in the emergency department: Clinician ‘gestalt’wins again. Emerg Med Austra 2016; 28: 658-665.

15. Helm R E, Klausner J D, Klemperer J D, Flint L M, Huang E. Accepted but unacceptable: peripheral IV catheter failure. J Infus Nurs. 2015; 38: 189-203.

16. Stevens R j, Mahadevan V, Moss A L. injury to the lateral cutaneous nerve of forearm after venous cannulation: a case report and literature review. Clin Anat. 2012; 25:659-662.

17. Bhattacharya S. Sushrutha - our proud heritage. Indian J Plast Surg 2009; 42: 223-225.

18. Mbamalu D. Banerjee A. Methods of obtaining peripheral venous access in difficult situations. Postgrad Med J 1999; 75: 459–462.

19. Datta S, Hanning C D. How to insert a peripheral venous cannula. Brit J hosp med 1990; 43: 67-69.

20. Chiao F B, Resta-Flarer F, Lesser J, et al. Vein visualization: Patient characteristic factors and efficacy of a new infrared vein finder technology. Br. J. Anaesth 2013; 110: 966–971.

21. AccuVein AV400 for vein visualisation. London: Medtech innovation briefing, 2014.

22. Van Der Woude O C, Cuper N J, Getrouw C, Kalman C J, De Graaff J C. The effectiveness of a near-infrared vascular imaging device to support intravenous cannulation in children with dark skin colour; a cluster randomised clinical trial. Anesth analg 2013; 116: 1266-1271.

23. Roberge R J, Kelly M, Evans T C, et al. Facilitated intravenous access through local application of nitro-glycerine ointment. Ann Emerg Med 1987; 16: 546-549.

24. Draft Guidance on Nitroglycerin. Washington: Food and Drug Administration, 2015.

25. van Loon F H J, Buise M P, Claassen J J F, Dierick-van Daele A T M, Bouwman A R A comparison of ultrasound guidance with palpation and direct visualisation for peripheral vein cannulation in adult patients: a systematic review and meta- analysis. Br. J. Anaesth 2018; 121: 358-366.

26. Keyes L E, Frazee B W, Snoey E R, Simon B C, Christy D. Ultrasound-guided brachial and basilic vein cannulation in emergency department patients with difficult intravenous access. Ann emerg med 1999; 34: 711-714.

27. Etezazian S. Evaluation of Success Rate of Ultrasound-Guided Venous Cannulation in Patients with Difficult Venous Access. Iran J Radiol 2010; 7: 61-65.

28. Guidance on the use of ultrasound locating devices for placing central venous catheters. London: National institute for health and care excellence, 2002.

29. Kim J H et al. Peripheral Vasoconstriction During Mental Stress and Adverse Cardiovascular Outcomes in Patients with Coronary Artery Disease. AHA J 2019, 125.

30. Khinda V, Rao D, & Sodhi S P S. Nitrous Oxide Inhalation Sedation Rapid Analgesia in Dentistry: An Overview of Technique, Objectives, Indications, Advantages, Monitoring, and Safety Profile. Intl J clin paed dent 2023, 16: 131–138.

31. Ichinose F, Roberts J D, Zapol W M. Inhaled Nitric oxide: A Selective Pulmonary Vasodilator: Current Uses and Therapeutic Potential. Circulation. 2004;109: 3106–3111.

Please click on the tables and figures to enlarge

The effect of remimazolam on a Parkinson’s patient

S. Madaan*¹ BDS (Lond), MFDS RCS (Ed), General dentist with a special interest in restorative and surgical dentistry, St Johns Dental Practice, Oxford, OX1 2LH.
A. Harris² BDS (Lond), DPDS, General dentist, visiting sedationist and SAAD accredited mentor, London, The Dentist Salisbury, SP1 2LH.
*Correspondence to: Dr Sita Madaan
Email: drsitamadaan@gmail.com
Madaan S, Harris A. The effect of remimazolam on a Parkinson’s patient. SAAD Dig. 2024: 40(II): 124-127 

Case Summary

A 63-year-old lady who is 5 ft 4 in and weighs 66 kg was diagnosed with Parkinson’s disease in 2016. Sedation with remimazolam was used with the aim of alleviating the patient’s fears so that we could remove her poor prognosis teeth and perform socket preservation in the upper left quadrant with the view to placing dental implants in the future. We found that using remimazolam enhanced her involuntary movements due to Parkinson’s disease, with each dose administered.

Patient details
Gender: Female
Age at start of treatment: 62 

Pre-treatment assessment

The patient presented with a left-sided swelling of the buccal space relating to two upper retained roots, not affecting the eye, and a toothache of two weeks. The patient stopped caring about her dental health after she was diagnosed with Parkinson’s disease in 2016 and started to neglect her dentition. She has started to feel self-conscious of her teeth but is extremely nervous of the dentist and has only presented because she had been suffering with pain for two weeks and had developed an abscess relating to some retained roots.

Relevant medical history

The patient is an ASA II. She was diagnosed with Parkinson’s disease in 2016. The patient also suffers from epilepsy and has been diagnosed as having grand mal seizures, although she had experienced a petit mal seizure in the last year. She has also been diagnosed with hypothyroidism. Overall, the patient is mobile, but says she is stiff in the morning and ok with stairs.

Medications

• Co-careldopa 50mg: primarily used to manage the symptoms of Parkinson's disease, however, it does not slow down the disease or prevent it from worsening
• Ropinirole 100mg a day: used to treat the symptoms of Parkinson's disease and restless legs syndrome - it can improve symptoms like shaking (tremors), slowness and stiffness
• Epilim 4mg bd: for epilepsy
• Levothyroxine 100µg od
• The patient also has a codeine allergy.

Previous sedation history

The patient has never been sedated before and has a BMI of 25. Her alcohol intake is 18 units per week with no history of taking benzodiazepines or recreational drugs. Her pre-operative blood pressure was 120/78.

Dental history

Irregular attender, has not attended for over 10 years.

Clinical examination

The patient had some trismus, not relating to dental infection. Several fractured teeth were seen with heavy evidence of parafunction and her muscles of mastication were tender because of this. There was evidence of heavy palatal erosion due to dietary acids, which the patient was unaware of. Calculus, plaque, and gingivitis were present throughout the mouth.

Bitewings and an OPG were taken for a full assessment of the patient’s dentition which showed:

LR7 is fractured and requires vitality testing and then cuspal coverage.

LR6 is a root filled tooth which has been prepared for a crown and will require a new crown.

LR5 is fractured with deep caries and has been recommended for extraction.

LL5 retained root recommended for extraction.

UR6 is a root fragment and requires extraction.

UR2-UL2 are fractured. Wear and exposed dentine can be seen clinically.

UL4 is a metal post crown with a questionable long-term prognosis.

UL6 and UL7 are root filled retained roots with signs of periapical pathology around UL7.

UL8 LL8 are unerupted.

There is mild generalized horizontal bone loss with vertical bone loss around the UL6 retained root.

Pre-treatment photographs

Diagnostic summary

1. Mild periodontitis (Stage 2 Grade A), which is active at present, with poor oral hygiene due to demotivation to look after oral health since onset of Parkinson’s disease.
2. Buccal caries on the lower premolars.
3. Retained roots which will require extraction. Multiple fractured teeth requiring cuspal coverage.
4. Palatal wear of the upper anteriors and fractured upper and lower incisors due to erosion, attrition and tooth position.
5. Post-extraction spaces which will require fixed, long-term space replacement to keep the bone stimulated and prevent bone loss from occurring in these areas.

Aims and objectives of treatment

1. Stabilisation of oral hygiene and gingival inflammation
2. Strengthening of enamel to reduce the risk of future decay and prevent tooth wear with high fluoride toothpaste
3. Elimination of any causes of disease, and to bring about a state of health, function and self-confidence
4. Alleviation of dental anxiety using treatment under IV sedation.

Treatment plan

1. Prevention advice: oral hygiene to be reinforced with emphasis on motivating the patient to introduce interdental cleaning into her regime. To discuss use of plaque disclosing tablets to aid removal of biofilm. Duraphat toothpaste to be prescribed to strengthen enamel against decay and prevent further tooth surface loss, which is of multifactorial origin (attrition and erosion)
2. Oral hygiene stabilisation with hygienist and periodontist involvement
3. Extraction of poor prognosis teeth and socket preservation in the upper left region as the patient would like to consider fixed space replacement, in the form of dental implants, if her oral hygiene permits this in the future. The patent is aware of the risks associated with dental implants including peri-implantitis. This phase of treatment will be carried out under IV sedation using remimazolam, due to the better sedative profile than that of the current drugs, including rapid onset and offset of sedation and a predictable duration of action
4. Caries stabilisation of lower premolars which require filling cervically
5. Fractured teeth to have cuspal coverage restorations and post crown to be monitored
6. Fractured anterior teeth and palatal exposed dentine to be repaired
7. Patient is also a heavy bruxist and will need some form of protection at the end of treatment. 

Treatment undertaken

• The initial presentation was as a new patient at an emergency appointment in February 2023 during which an assessment was carried out, a periapical radiograph (PA) was taken and referral for full mouth Orthopantomogram (OPG) made. Antibiotics were prescribed to prevent the further spread of infection and the patient was advised to return for a full mouth detailed clinical examination. Even though there were no signs of septicaemia or cellulitis, the patient’s reduced co-operation and compromised oral hygiene until this point was taken into consideration as a risk factor for further spread of infection.
• The patient then saw the periodontist and had multiple sessions with the hygienist every three weeks where disclosing tablets were used to aid oral hygiene instruction.
• She expressed her concerns about undergoing dental treatment and explained that she was nervous. We discussed the possibility of sedation, and she filled out an Indicator of Sedation Need form. Her pre-operative sedation score was 21 indicating a very high Modified Dental Anxiety Scale (MDAS) score. Given her underlying medical health and considering the treatment complexity this gave a score of ‘very high need’ for sedation.
• We elected to use remimazolam due to its superior properties over midazolam such as rapid induction, rapid recovery, and less respiratory depression.¹ The patient then attended in May 2023 for extraction of all retained roots, UR5, UL6, UL7, LR5, LL5 and socket preservation in the upper left quadrant (ULQ). At this stage the drug was in its infancy for use in general dental practice sedation cases, as remimazolam was approved for use in dentistry in the UK in January 2023.

Treatment findings

A total of 17.5 mg of remimazolam was administered over the course of 1 hour 15 mins. An initial 5 mg dose was administered. With every subsequent 2.5 mg increment given the patient demonstrated jerky movements and signs of un-cooperation. Her legs started to jerk, and her jaw would clamp down which would impede the procedure but then she would settle down. A brief timeline of events is as follows:

11.54: Rapid induction of remimazolam (5 mg over 2 mins)

11.58: The patient did not like the administration of local anaesthetic

12.06: 2.5 mg administered, patient became unco-operative and was very jerky during the upper left quadrant extractions

12.28: 2.5 mg administered. The patient reported ‘this is a great experience’.

12.32: 2.5 mg administered. Bone grafting of the upper left quadrant.

12.36: The patient was much more relaxed.

12.42: Sutures placed and collagen plug.

12.53: Patient is relaxed during further suturing

13.00: 2.5 mg administered, patient is unco-operative again

13.10: Patient is more aware of what is going on

13.13: 2.5 mg administered

13.20: Patient did not like local anaesthetic (LA)

13.35: Patient was co-operative for extractions

13.49: Patient settled down and was more co-operative but was aware of treatment

13.55: Remaining lower surgical extraction was completed

14.00: Procedure finished

Long term treatment and future considerations

 In future, we could consider giving a reduced dose over a longer administration period. However, reducing the duration of the drug use would make it unsuitable for long surgical types of procedures. It is worth considering that now that she has been reintroduced to dental work after several years, she may have a lower sedation score in future and may not need treatment under sedation going forward. Her next phase of treatment would be restorative and only when we come to implant placement may she feel a need to revisit the idea of sedation.

We could consider trying to manage her pre-operative anxiety using other relaxation techniques such as deep relaxation with diaphragmatic breathing or hypnotherapy². We could also consider the use of midazolam as there are case reports to support the use of this drug to ease the symptoms of Parkinson’s disease.²

At present the patient is still mid-restorative phase due to a fall and subsequent hip injury, causing a delay in the completion of her treatment. The anterior restorative work which has been carried out so far was unremarkable and was undertaken under local anaesthetic with ease.

Discussion and reflection about case presented

As remimazolam was only approved for use in dentistry in UK in January 2023, the seditionist had limited experience of practical cases with this drug. In hindsight, she could have started with a lower induction dose and could have given lower top-up doses, as the patient swung from being co-operative to unco-operative immediately after top-up increments.

On a follow up phone call the next day, the patient reported that the sedation was ‘fabulous’, she didn’t remember anything about the treatment apart from the tail end of the appointment and the patient was much more co-operative at this point. She felt normal upon leaving the practice and was delighted with the outcome.

Oral surgery can be difficult in patients with chorea-like dyskinesia (involuntary movements) which is common in those on long-term levodopa medication for Parkinson's disease,³ and we know of no conclusive evidence to indicate whether conscious sedation with midazolam is effective in such cases. However, there are case reports of a patient in whom levodopa-induced chorea-like dyskinesia disappeared when midazolam was given intravenously for conscious sedation, so this drug could be preferred in such patients.³

References 

1. Kim K M. Remimazolam: Pharmacological Characteristics and Clinical Applications in Anaesthesiology. Anesth Pain Med (Seoul) 2022; 17: 1–11.

2. Wang R, Huang X, Wang Y, Akbari M. Non-pharmacologic approaches in preoperative anxiety: a comprehensive review. Front Public Health 2022, 10: 852673.

3. Shibuya M, Hojo T, Hase Y, Fujisawa T. Conscious sedation with midazolam intravenously for a patient with Parkinson's disease and unpredictable chorea- like dyskinesia. Br J Oral Maxillofac Surg 2018; 56: 546-548. 

Self-help resources incorporating cognitive behavioural techniques for patients with dental phobia: what’s available?

J. Hare DHealthPsy CPsychol AFBPS*¹
T. Newton BA PhD CPsychol CSci AFBPsS FHEA^2
1Consultant Health Psychologist, Dental Psychology Service, Guy’s and St Thomas’ NHS Foundation Trust and SAAD Editorial Board Member
²Professor of Psychology as Applied to Dentistry, King’s College London
*Correspondance to: Jennifer Hare
Email: Jennifer.Hare@gstt.nhs.uk
Hare J, Newton T. Self-help resources incorporating cognitive behavioural techniques for patients with dental phobia: what’s available? SAAD Dig. 2024: 40(II): 128-132

The launch of the new NHS England Clinical Standards for Dental Anxiety Management¹ at the beginning of last year demonstrates a significant shift from the formerly titled Service standards for Conscious Sedation in a primary care setting. The clinical guide now includes a range of approaches which comprise behavioural techniques as both a stand-alone anxiety management strategy or as a complementary approach to support conscious sedation and general anaesthesia. The guide makes the important distinction between ‘trait anxiety’ (the more enduring apprehension concerning dental treatment that a person generally feels when contemplating, or engaging with, dental treatment) and ‘state anxiety’ (the individual’s degree of concern at a specific point in time when faced with a particular aspect of dental treatment such as local anaesthetic injections). This distinction is important since approaches to managing the two forms of anxiety may differ.

While conscious sedation and general anaesthesia offer an invaluable approach to provide dental treatment with increased comfort and reduced anxiety to individuals, there is also an appreciation that, when used in isolation, they may not target the underlying fear or trait anxiety. Therefore, opportunities to integrate pharmacological interventions alongside approaches based on cognitive behavioural (CB) techniques may afford the prospect to work on both state and trait anxiety simultaneously, supporting a rehabilitation model of dental fear.²

In recognition of this, the authors published an article in the 2018 SAAD Digest on Cognitive Behavioural Therapy (CBT) services and training options in the UK for dental professionals.³ However, since then a number of self-help CBT guides have become available to support patients and their dental teams which provide dental anxiety management interventions informed by CB principles and techniques. These resources support the implementation of some of the more advanced interventions referenced in the new standards1 which include the use of communication tools to support patient care.

This article aims to briefly outline two resources currently available for children and adults and consider their application for dental anxiety management.

1. Your teeth, you are in control

Produced by a team of experts in the field under the leadership of Sheffield Teaching Hospitals NHS Foundation Trust with collaboration between Kings College London, University of Reading, University of Glasgow and Five Areas Ltd, Your teeth, you are in control is a self-help CBT-based resource for young people (aged 9 to 16 years), with supplementary resources for parents and dental teams.⁴

The authors suggest it is used with young people experiencing mild to moderate trait dental anxiety requiring non-urgent treatment. It is written to support the provision of a course of treatment with information on the dental setting, some basic dental procedures and specific tools and strategies to manage the physical sensations of anxiety. It also includes access to valuable resources to increase children’s sense of control including ‘Message to the dentist’ (Figure 1) which also facilitates enhanced communication between the child and the dental team, as well as a ‘stop signal signed agreement’. These are evidence-based techniques shown to reduce anxiety and distress in the dental setting.^5,6 The guide also provides opportunities for the child and family to think about what went well at each visit, providing feedback on positive coping, an evidence-based CB-technique to support anxiety management in children.⁶ A full step-by-step process of how to implement the self-help guide is outlined in the BDJ Team article by Zoe Marshman,⁴ along with information on accompanying materials and guides to support parents / guardians and dental teams.

While the content and components of the self-help guide all hinge upon evidence-based CB-techniques, the guide itself was created as part of a collaborative research study with patient and public involvement.⁷ This preliminary investigation demonstrated encouraging results for the 48 children (out of 56 initially recruited) who completed the study, which comprised three dental treatment visits and pre- and post-treatment questionnaires.

Self-reported dental anxiety significantly reduced and health-related quality of life significantly increased following the use of the self-help guide with 60% of young people reporting feeling ’a lot less worried’ about visiting the dentist. The study further demonstrated high levels of acceptability of the self-help guide among young people and stakeholders, with recommendations to run a full randomised controlled trial (RCT) which is currently underway.

The CALM trial protocol is a four-year RCT being run across 30 primary care dental sites including general dental practices and primary dental community clinics across some of the most deprived areas in the UK with higher than average caries rates. The aim of the RCT is to establish the clinical and cost-effectiveness of the self-help CBT guide⁸ and we look forward to seeing the results in due course.

In addition to these research studies, a service evaluation published in 2019 reported encouraging findings on the use of the guide in a single general dental practice.⁹ Statistically significant reductions in dental anxiety reported using the Children’s Experiences of Dental Anxiety Measure (CEDAM) were seen within the evaluation’s 84 included young patients, with a mean age of 10.9 years old. This service evaluation demonstrates the ‘real-world’ applicability of the resource.

At present Your teeth, you are in control and the accompanying user-friendly resources are available to purchase in paper copy via the University of Sheffield website¹⁷ and the single-page ‘Message to the dentist’ is currently available to download for free (in a number of languages) via the Living Life to the Full (LLTTF) website.18 To learn more about the intervention and the resources, please visit these two websites.

2. Getting the dental care you need: getting through an urgent dental appointment

This CBT-based self-help book which is available both in printed form or online (Figure 2) is written for people with dental fear who now require urgent dental treatment and who may be in pain or have other urgent symptoms.¹⁰ Written by experts in dentistry and CBT, this practical resource teaches key skills to help people experiencing dental anxiety. It provides a structure of intervention for dental practitioners and teams wanting to support their patients, as well as for patients wanting to learn anxiety-management techniques they can use themselves or to help support a conversation with their dentist.

The content covers what might have caused dental anxiety onset and supports the learning of five strategies to manage dental fear in order to get through an urgent dental appointment.

These strategies consist of:

1. Using topical numbing gel before an injection
2. Agreeing start / stop signals
3. Learning calm-controlled breathing
4. Techniques to shift focus to the whole body and
5. Listening to music or audiobooks.

There is also a specific section on ‘getting though a tooth extraction’ to prepare an individual by advising what to expect. In addition, the book aims to support the patient to communicate their dental anxiety fears to their dental practitioner and state how they wish to self-manage their anxiety during the treatment. Using the ‘dental care agreement’ (similar to the principles of ‘Message to the dentist’ outlined in the child-oriented resource) the two-page document is jointly reviewed and signed, with a commitment to support the patient’s choices and preferences agreed and the patient and clinician working together for an effective treatment outcome. The agreement helpfully includes a ‘my emergency dental kit’ checklist of treatment preferences to be agreed at the appointment which affords a greater sense of patient choice and control; vital ingredients in dental anxiety management.¹¹

The authors suggest that the book can be both read as a standalone self-help guide for patients which can be applied in their own appointments or could be provided with support from dental teams.

While there are no specific research studies evaluating the use of this guide in practice as yet, the principles and evidence base of CBT are well-documented for dental fear and anxiety.^12-16

At present, the Getting the dental care you need: getting through an urgent dental appointment book is available to purchase via the Living Life to the Full (LLTTF) website,¹⁸ where more information is available on how to use the resource, supporter notes and training information.

Final thoughts and conclusion

These two CBT-informed resources provide an opportunity for patients and practitioners to incorporate valuable CB-techniques into their dental anxiety management approach. They provide a user-friendly way to support both the patient and the dental team apply the techniques in practice, without necessarily completing specific training in CBT per se. It is important to note that using these resources in a standalone fashion cannot be considered as delivering a full course of CBT, as this requires appropriate training and cannot be used as a one-off, ad hoc technique.³

As we await the implementation guidance for the new Clinical standards for dental anxiety management, these resources, along with low level behavioural management techniques, provide a helpful approach to utilise in primary care settings. The authors appreciate the time required to incorporate these approaches effectively and it is sincerely hoped that this will be duly considered in the commissioning of services across all tier levels of dental care provision. Indeed, the concept of allowing for longer appointments is included in the new standards’ appendix¹ where, over time as trust and rapport are built and dental anxiety reduced, working towards care delivery in standard appointment times might be a more realistic and achievable goal.

Figures

References

 1. NHS England (2023). Clinical standards for dental anxiety management. Available from: https://www.england.nhs.uk/long-read/clinical-guide-for-dental-anxiety-management/

2. Newton T, Gallagher J, Wong F. The care and cure of dental phobia: the use of cognitive behavioural therapy to complement conscious sedation. Faculty Dental J 2017; 8: 160-163.

3. Hare J, & Newton J T. Cognitive Behavioural Therapy (CBT) for dental phobia: services and training options for dental professionals. SAAD Dig 2018; 34; 69-71.

4. Marshman, Z. Your teeth you are in control. BDJ Team 2017; 4: 15-17.

5. Richardson P H, Black N J, Justins D M, Watson R J. The use of stop signals to reduce the pain and distress of patients undergoing a stressful medical procedure: an exploratory clinical study. Br J Med Psychol 2009; 72: 397–405.

6. Pickrell J E, Heima M, Weinstein P, Coolidge T, Coldwell S E, Skaret E, Castillo J, Milgrom P. Using memory restructuring strategy to enhance dental behaviour. Int J Paediatr Dent 2007; 17: 439–448.

7. Porritt J, Rodd H, Morgan A, Williams C, Gupta E, Kirby J, Creswell C, Newton T, Stevens K, Baker S, Prasad S, Marshman Z. Development and Testing of a Cognitive Behavioral Therapy Resource for Children's Dental Anxiety. JDR Clin Trans Res 2017; 2: 23–37.

8. Bux S, Porritt J, Marshman Z. (2019). Evaluation of Self-Help Cognitive Behavioural Therapy for Children's Dental Anxiety in General Dental Practice. Dent J (Basel) 2019; 7: 36.

9. Marshman Z, Rodd H, Fairhurst C, Porritt J, Dawett B, Day P, Innes N, Vernazza C, Newton T, Ronaldson S, Cross L, Ross J, Baker S R, Hewitt C, Torgerson D, Ainsworth

H. The CALM trial protocol: a randomised controlled trial of a guided self-help cognitive behavioural therapy intervention to reduce dental anxiety in children. Trials 2023; 24: 15.

10. Williams C, Campbell C, Johnston E, Newton T. Getting the dental care you need: Getting through an urgent dental appointment. Clydebank: Five Areas Ltd, 2023

11. Wardle J. (1982). Management of dental pain. York: Paper presented at British Psychological Society.

12. Öst L, Skaret E. Cognitive Behaviour Therapy for Dental Phobia and Anxiety. London: Wiley, 2013.

13. Kvale G, Berggren U, Milgrom P. Dental fear in adults: a meta-analysis of behavioural interventions. Community Dent Oral Epidemiol 2004; 32: 250-264.

14. Wide Boman U, Carlsson V, Westin M, Hakeberg M. Psychological treatment of dental anxiety among adults: a systematic review. Eur J Oral Sci 2013; 121: 225-234.

15. Kani E, Asimakopoulou K, Daly B, Hare J, Lewis J, Scambler S, Scott S, Newton J T. Characteristics of patients attending for Cognitive Behavioural Therapy at one specialist unit for dental phobia in the UK and outcomes of treatment. Br Dent J 2015; 219: 501-506.

16. Porritt J, Jones K, Marshman Z. Service evaluation of a nurse-led dental anxiety management service for adult patients. Br Dent J 2016; 220: 515-20.

Websites:

17. University of Sheffield: https://www.sheffield.ac.uk/dentalschool/research/person-centred-population/child-dental-anxiety/resources (accessed 01/05/24).

18. Living Life to the Full (LLTTF) https://llttf.com/product/getting-the-dental-care-you-need/ (accessed 01/05/24).

 Laleh Sharifian

Dentistry has been the only profession on my radar for as long as I can remember! Not having any family in the medical world and having a rather odd dentist as a child, I am surprised this obsession managed to stick around and I was lucky enough to join the prestigious United Medical and Dental Schools (UMDS) of Guy’s and St Thomas’ Hospitals to study dentistry. At my interview I remember talking about how excited I was to treat nervous patients and to learn about sedation. As an undergraduate, I was awarded the Malleson prize for my final year research project on the psychosocial effects of tooth loss.

I qualified in 1999 from UMDS and enrolled on the diploma for sedation soon after, whilst doing surgical and restorative house jobs at Guy’s. Blessed to have been taught by the finest leading tutors in this field, including Meg Skelly, Derek Debuse, David Craig and Carole Boyle, I embarked on a journey as a general dental practitioner (GDP) whilst using my sedation skills in primary care.

Most of my career has been as a private GDP in London and I spent 15 years at the same practice, building continuous care with patients I adored. I noticed an increase in demand for sedation in primary care and wanted to make sedation accessible to more patients and dentists. I set up a peripatetic service so patients were able to have their treatments with their own dentist and I was able to utilise technology and the luxury of mobility to deliver a bespoke anxiety and IV sedation service for those patients and dentists. I did this alongside dentistry for a few years before deciding to dedicate myself full time to this exciting and growing field. I wrote a difficult email to my patients explaining my decision and in 2020 I put my proverbial dental tools down.

I now practise sedation in the south east of England for 40 practices and sedate around 250 patients a year. Alongside this, I am dedicated to teaching and learning and am tremendously honoured to be part of the faculty at SAAD. I also teach life support courses, mainly ILS, for dental practices. I am a sedation supervisor for nurses and dentists training in sedation and also an examiner for the Royal College of Surgeons of Edinburgh. I also undertake expert witness work in relation to sedation and engage in lectures and talks for dental associations both locally and nationally.

SAAD has been an inspiration to me throughout my career, and I am privileged and excited to have been chosen as a co-opted member of the SAAD Board. I hope to utilise my experience of peripatetic sedation services in primary care and continue to promote and expand this incredible area.

Outside of sedation, I consciously engage in anything culinary and travel-related. Living in the UK, we are able to travel for just a few hours to discover entirely different surroundings, people, language, food and wine. I absolutely love to travel in this way every few weeks and find this to be life’s natural sedative