Effects of Dexmedetomidine During Radiofrequency Ablation of Abdominal Tumours

Study Overview
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Brief Summary
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The purpose of he study is to evaluate effects of dexmedetomidine on pain during radiofrequency ablation of liver and kidney tumours.

Detailed Description
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Although radiofrequency ablation (RF) is accepted as the best therapeutic choice for patients with early stage hepatocellular carcinoma when liver transplantation or surgical resection are not suitable options, it is still performed only in a few hospitals and experience is so far limited (Goldberg & Ahmed, 2002; Shiina et al., 2005). In addition, RF ablation is emerging as a viable alternative to surgery for inoperable patients with limited hepatic metastatic disease, especially from colorectal cancer. Although radiofrequency ablation has been accepted as a safe and effective treatment for liver and kidney tumours, there are few studies addressing periprocedural pain. Thus, the optimal anaesthetic procedure is still to be determined. Currently at our institution RF is performed as monitored sedation procedure using remifentanil infusion supplemented with midazolam boluses, when considered necessary. However, when using remifentanil and midazolam combination it is quite difficult to avoid too deep respiratory depression. Dexmedetomidine is an α2-adrenoreceptor agonist with sedative, analgesic and anxiolytic effects, and it has more selective α2-adrenergic effect than clonidine. Dexmedetomidine has a great deal of potential in this arena given its analgesic and anxiolytic properties while preserving respiratory drive (Bergese SD et al., 2010). All patients will receive dexmedetomidine 0.4 µg/kg/hr infusion from the start of procedure. The infusion will be continued during the whole RF procedure. At the same time all patients will receive remifentanil infusion according to TCI (target controlled infusion) protocol. Plasma concentration target will be set from 0.5 ng/ml and, if necessary, will be increased to achieve a comfortable state of patient (Ramsey Sedation Scale: 2-3).

Official Title
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Effects of Dexmedetomidine on Periprocedural Pain During Radiofrequency Ablation of Liver and Kidney Tumours

Conditions
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Cancer of Kidney and Renal Pelvis, Cancer of Liver

Intervention / Treatment
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* Drug: Dexmedetomidine


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: liver or/and kidney cancer for which radiofrequency ablation procedure is planned signed informed consent form Exclusion Criteria: patient refusal pregnancy known allergy to dexmedetomidine or remifentanil atrioventricular block grade II or III or other significant cardiac conduction disturbance stroke low blood pressure not responding to treatment

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 80 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Dexmedetomidine<br> | Drug: Dexmedetomidine<br>* Dexmedetomidine 0.4 µg/kg/hr infusion during RF procedure<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Patient Satisfaction With Sedation Technique | Rating of how satisfied the patient was with their sedation on a scale of 1-5 with 1 being very dissatisfied and 5 being extremely satisfied | After completion of procedure (within 15 minutes) | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Vital signs: blood pressure, oxygen saturation, heart rate, breathing rate |  | During procedure and up to 2 hours stay at the post-anesthesia care unit | 
| Ramsey Sedation Scale Score | Rating of depth of sedation. Scale 1 - 6, 1 being wide awake and 6 being non-responsive | During the procedure and up to 2 hours stay at the post-anesthesia care unit | 
| Maximal pain intensity | The 11-point Numerical Rating Scale (NRS) to assess periprocedural pain. Scale of 0-10, with 0:no pain and 10: pain as bad as it could be | During procedure and up to 2 hours stay at the post-anesthesia care unit |