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Patterns, incidence and predictive factors for pain after interventional radiology
Clinical Radiology (2005) 60, 1188–1194
Patterns, incidence and predictive factors for pain after interventional radiology A. Englanda,*, C.L. Tama, D.E. Thackera, A.L. Walkera, A.S. Parkinsona, W. DeMellob, A.J. Bradleya, J.S. Tucka, H.-U. Laaschc, J.S. Butterfielda, R.J. Ashleigha, R.E. Englanda, D.F. Martina,d Departments of aRadiology, bAnaesthesia, South Manchester University Hospitals NHS Trust, Southmoor Road, cRadiology, Christie Hospital NHS Trust, Manchester, and dFaculty of Health, University of Central Lancashire, Preston, UK Received 11 March 2005; accepted 5 May 2005
KEYWORDS Interventional procedures, complications; Interventional procedures, quality assurance; Pain; Analgesia
AIM: To evaluate prospectively the pattern, severity and predictive factors of pain after interventional radiological procedures. MATERIALS AND METHODS: All patients undergoing non-arterial radiological interventional procedures were assessed using a visual-analogue scale (VAS) for pain before and at regular intervals for 24 h after their procedure. RESULTS: One hundred and fifty patients (87 men, mean age 62 years, range 18–92 years) were entered into the study. Significant increases in VAS score occurred 8 h after percutaneous biliary procedures (C47.7 mm, SD 14.9 mm; pZ0.001), 6 h after central venous access and gastrostomy insertion (C23.7 mm, SD 19.5 mm; pZ0.001 and C28.4 mm, SD 9.7 mm; pZ0.007, respectively) and 4 h after oesophageal stenting (C27.8 mm, SD 20.2 mm, pZ0.001). Non-significant increases in VAS pain score were observed after duodenal and colonic stenting (duodenal: C5.13 mm, SD 7.47 mm; pZ0.055, colonic: C23.3 mm, SD 13.10 mm, pZ0.250) at a mean of 5 h (range 4–6 h). Patients reported a significant reduction in pain score for nephrostomy insertion (K28.4 mm, SD 7.11 mm, pZ0.001). Post-procedural analgesia was required in 99 patients (69.2%), 40 (28.0%) requiring opiates. Maximum postprocedural VAS pain score was significantly higher in patients who had no preprocedural analgesia (pZ0.003). CONCLUSION: Post-procedural pain is common and the pattern and severity of pain between procedures is variable. Pain control after interventional procedures is often inadequate, and improvements in pain management are required. Q 2005 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.
Introduction There has been rapid growth of interventional radiology during the past 5–10 years.1 Despite this, there has been little documentation or study about pain after radiological intervention.1–4 As interventional radiological procedures become more
* Guarantor and correspondent: A. England, Department of Radiology, South Manchester University Hospitals NHS Trust, Southmoor Road, Manchester M23 9LT, UK. Tel.: C44 161 2916200; fax: C44 161 2916201. E-mail address: [email protected] (A. England).
invasive, complex and readily available, issues of post-procedural pain management are ever more critical. To our knowledge, the incidence and pattern of pain after interventional radiology has never been evaluated. We undertook a prospective study to assess the incidence and pattern of pain after radiological intervention. An additional objective of the study was to attempt to identify any predictive factors for pain after intervention.
Materials and methods All inpatients and outpatients who underwent
0009-9260/$ - see front matter Q 2005 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved. doi:10.1016/j.crad.2005.05.012
Patterns, incidence and predictive factors for pain after interventional radiology
Table 1
Procedures investigated in the study.
Table 2
Predictive factors analysis.
Procedure
Predictive factor
Percutaneous biliary procedures (PTC)a Oesophageal stenting Oesophageal dilatation Duodenal stenting Colonic stenting Percutaneous gastrostomy Central venous access Percutaneous nephrostomy (PCN) Ureteric stenting Liver biopsy
Gender Age ASA grade Pre-procedural analgesia (!6 h) Type of pre-procedural analgesia Pre-procedural VAS pain score Procedure type Intra-procedural fentanyl consumption Intra-procedural midazolam consumption Operator Procedure time Procedure difficulty Post-procedural analgesia Type of post-procedural analgesia
a PTC includes percutaneous biliary drainage and stenting procedures.
interventional radiological procedures from October 2003 to June 2004 were asked to participate in the study. Patients were excluded from the study if (a) they were younger than 18 years; (b) they were unable to understand the nature of the study or complete the data collection sheet. Only patients who were referred for non-arterial radiological intervention were included in the study. Patients referred for vascular arterial intervention were excluded for logistical reasons. Non-arterial interventional procedures are listed in Table 1. The survey was conducted by three of the authors; the individual performing the interviews was not involved in any of the interventional radiological procedures. Potential patients were identified on arrival in the interventional radiology department. The study was then explained to the patient and if they agreed the patient was interviewed before the procedure. The visual analogue scale (VAS) format was used to measure the subjective feeling of pain both before and after the procedure. For this, each patient was given a data collection form, which contained the VAS pain scale. They subjectively assessed their feeling of pre-procedural pain and marked this accordingly on the VAS scale. The options ranged from ‘No pain’ to ‘Worst pain ever’. The patient was then counselled as to the requirements of the study after the procedure, which included a description of the VAS process to be completed on the ward or at home. Patients were asked to quantify their feeling of pain at 2, 4, 6, 8, 12, 16, 20 and 24 h after the procedure using the VAS pain scale. All of the VAS pain scales were given to the patient to take back to the ward or home for selfcompletion. The parameters investigated pre-, intra- and post-procedure are listed in Table 2. Each performing interventional radiologist was graded according to their skill level (consultant or specialist registrar
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in training). Survey interviews with patients took place at least 30 min before the procedure. Postprocedural data collection forms were collected 24 h after the procedure. At this point any history of analgesia consumption or adverse event was recorded. If the patient was at home, the patient completed the data collection sheet and returned it to the interventional radiology department in a prepaid envelope. The study was undertaken as an audit with no alteration to clinical practice and as such formal local ethics committee approval was not sought. All patients included agreed to complete the questionnaire and were fully aware of the nature and requirements of the investigation.
Analysis of data Data acquired from the VAS pain questionnaires was taken as a length measurement (mm) using a ruler. All data were then entered into SPSS 11.01 (SPSS, Chicago, IL, USA). Data analysis was performed with the Student’s t-test or an analogous non-parameteric test where appropriate. The level of statistical significance was set at 0.05. The patients were grouped according to their procedure. Pre-procedural VAS pain scores were then compared with the maximum VAS pain scores during the 24-h data collection period. Data were analysed to assess for significant changes in postprocedural pain score. Patients were also grouped into a pain or no-pain category depending on the difference between their pre-procedural pain score and maximum VAS post-procedure pain score. We considered a change of C10.0 mm to represent an increase in pain post-procedure. Variables described in Table 2 were then analysed for their effect on post-procedural pain.
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Sedoanalgesic regime For percutaneous procedures all patients received local skin anaesthetic of 5–10 ml of 1% lidocaine. Tunnelled central venous access was the only exception, patients in this group had lidocaine 1% with adrenaline 1 in 200,000 units (Xylocaine; Astra Zeneca, UK). Depending on the type of procedure and peri-procedural pain different levels of intravenous sedation and analgesia were used. At our institution the drugs used for conscious sedation are midazolam (Hypnovel; Roche Products Ltd, UK) and fentanyl (Sublimaze; Janssen-Cilag, UK). The exact sedoanalgesic regimes used for the study group are listed in Table 3.
Figure 1 A whisker and bar graph to showing the intensity of pain before the interventional radiological procedure.
Pre-procedural analgesia consumption
Results A total of 150 patients who fitted the selection criteria participated in the study. The mean age of the study group was 62 years (range 18–92 years); 87 (57.0%) were men. Twenty-seven patients (18.0%) were ASA grade 1, 87 (58.0%) were grade 2 and the remaining 36 (24.0%) patients were ASA grade 3. There was no patient included in the study with ASA grades 4 or 5.
Pre-procedural pain Inspection of the pre-procedural VAS scores indicated that 88 (58.7%) patients reported pain R10.0 mm. Of the 88 patients, 43 (28.7%) had pre-procedural VAS pain scores R30.0 mm. The pre-procedural VAS scores are graphically described in Fig. 1. The mean pre-procedural VAS pain scores for each procedural group are listed in Table 3. Nephrostomy patients had the highest median preprocedural VAS score (C34.3 mm SD 27.4 mm). Table 3
Seventy-nine (52.7%) of the patients arrived in the interventional department having been administered analgesia within 6 h. Of these patients, 50 (63.3%) patients had non-opiate and 29 (36.7%) patient had opiate analgesia. Of the patients with no pre-procedural pain (nZ62), 21 (33.9%) patients had received analgesia with 6 h.
Post-procedural pain Significant increases in VAS score occurred 8 h after percutaneous biliary procedures (C47.7 mm, SD 14.9 mm; pZ0.001), 6 h after central venous access and gastrostomy insertion (C23.7 mm, SD 19.5 mm; pZ0.001 and C28.4 mm, SD 9.7 mm; pZ 0.007, respectively) and 4 h after oesophageal stenting (C27.8 mm, SD 20.2 mm, pZ0.001). Non-significant increases in VAS pain score were observed after duodenal and colonic stenting (duodenal: C5.13 mm, SD 7.47 mm; pZ0.055, colonic: C23.3 mm, SD 13.10 mm, pZ0.250) at a
Summary of pre-procedural VAS pain score and procedural parameters.
Procedure
n
Procedure time (min)
Procedural
Pre-VAS scores (mm)
Mean
Range
Sedation
IV analgesia
Mean
SD
PTC Oesophageal stenting Duodenal stenting Colonic stenting Gastrostomy Oesophageal dilatation Central venous access Nephrostomy Liver biopsy Ureteric stenting
14 38 9 3 15 12 23 23 10 3
45.7 30.1 39.4 40.0 40.0 32.1 34.3 43.6 15.0 63.3
25–75 15–60 20–60 30–45 25–120 20–40 30–60 20–90 10–20 40–90
14 (100%) 38 (100%) 9 (100%) 3 (100%) 15 (100%) 12 (100%) 23 (100%) 19 (83%) 0 (0%) 1 (33%)
12 (86%) 38 (100%) 9 (100%) 3 (100%) 15 (100%) 12 (100%) 1 (4%) 22 (96%) 0 (0%) 1 (33%)
15.4 20.5 21.1 13.3 10.1 13.3 16.7 34.4 16.0 10.0
16.7 19.9 37.5 23.1 9.8 23.1 18.7 27.4 32.0 17.3
Patterns, incidence and predictive factors for pain after interventional radiology
Table 4
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Post-procedural changes in VAS pain score.
Procedure
PTC Oesophageal stent Duodenal stent Colonic stent Gastrostomy Oesophageal dilatation Nephrostomy Central venous access Ureteric stent Liver biopsy
n
14 38 9 3 15 12 23 23 3 10
Maximum visual analogue pain score
p-Value
Mean (mm)
SD (mm)
Peak time
47.7 27.8 5.13 23.3 28.4 5.8 K28.4 23.7 16.6 15.0
14.9 20.2 7.47 13.10 9.7 22.0 7.11 19.5 5.7 49.5
8 4 8–12 6 6–8 2 24 6 2 8
mean of 5 h (range 4–6 h). Patients reported a significant reduction in pain score for nephrostomy insertion (K28.4 mm, SD 7.11 mm, pZ0.001). Postprocedural VAS pain scores are listed in Table 4, pain patterns after interventional radiological procedures are displayed graphically in Figs. 2 (a–d). Postprocedural analgesia was required in 99 patients (69.2%), 40 (28.0%) required opiates.
Predictive factor analysis Pre-procedural VAS pain score and pre-procedural
0.001 0.001 0.055 0.250 0.007 0.377 0.001 0.001 0.363 0.105
analgesia were the only two statistically significant factors identified in the analysis. Patients who had no pain before the interventional radiological procedure had significantly greater increases in their pain score post-procedure (pZ0.001). Also, patients who received no pre-procedural analgesia had significantly higher post-procedural pain when compared with patients who had pain relief within 6 h before the procedure (PZ0.04). This association is linear, patients who have moderate analgesia had less risk of getting pain postprocedure when compared with the mild analgesia
Figures 2 (a–d) Line graphs showing the individual patterns and intensities of pain after specific radiological interventional procedures.
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Table 5 Predictive factors for pain following radiological intervention. Variable
Group Pain
p-Value No-pain
Age, years 61.6 SD 16.0 62.2 SD 14.5 Gender, M:F 48:29 39:24 ASA grade I 14 13 II 50 37 II 23 13 Pre-procedure 12.3 SD 15.8 29.0 SD 27.8 VAS, mm Procedure 36.2 SD 17.1 35.1 SD 16.2 time, min Fentanyl, mg* 73.8 76.1 Midazolam, 68.1 80.8 mg* Operator Trainee 51 39 Consultant 36 24 Pre-procedure analgesia consumption None 47 24 Mild 20 15 Moderate 6 9 Strong 14 15 Post-procedure analgesia consumption None 23 25 Mild 29 17 Moderate 7 7 Strong 28 14
0.457 0.256 0.334
0.001 0.406 0.676 0.073
0.407
0.04
0.128
group. A full detailed list of the predictive factors analysed is summarized in Table 5.
Discussion Despite the growth and interest in interventional radiology in recent years there are limited studies on pain associated with interventional procedures. We have performed a prospective study investigating the issue of pain after intervention. To quantify the patient’s experience of pain after radiological intervention we used the VAS pain scale. Although this method is not perfect, it is a common way to assess pain.1,5 From the preprocedural interview it was apparent that there was a wide range in the levels of pain experienced by patients arriving in the department. Furthermore, there is a wide range in the prescribing practices for patients attending the interventional radiology department. The present results are in keeping with other published studies highlighting percutaneous biliary procedures as amongst the most painful interventional radiological procedures. 3,6,7 Studies by Harshfield et al.6 and Lee et al.,7 advocate the
use of epidural and general anaesthesia in certain biliary procedures to reduce pain. Lidocaine is the most commonly used local anaesthetic currently in use.4 Despite is wide use in interventional radiology the duration of action rarely exceeds 2 h. Suggestions have been made regarding the combined use of longer-acting local anaesthetics, e.g. ropivacaine hydrochloride (Naropin; Astra Zeneca, UK).4 Combined use of short and long-acting local anaesthetic may have particular benefit in percutaneous interventional procedures where peak pain times are 6–8 h, well beyond the range of lidocaine. Some use premedication as a method of sedoanalgesia as an adjunct to intra-procedural analgesia and sedation.4 In the present study, patients who had pre-procedural analgesia were less likely to get increases in postprocedural pain (pZ0.04). Data from the present study supports the administration of pre-procedural analgesia as a method of reducing post-procedural pain. If lengthy post-procedural pain is anticipated early involvement of the hospital-based ‘Acute Pain Service’ is advisable as the team has access to an entire spectrum of conventional and integrative modes of pain management.4 Procedure duration has previously been identified as a critical parameter in the pain experience.8 A study of abdominal interventional procedures confirmed that patients reporting greater pain had technically more difficult procedures and more time-intensive procedures.9 In the present study there was no statistical significance when comparing pain with procedure length (pZ0.406). Two reasons can be suggested for this: (a) the majority of patients had procedures of the same duration and complexity; or (b) the lengthy procedures were for patients with pre-procedural pain and there were existing pathways in place for dealing with post-procedural pain. Patients who have had lengthy procedures may require close attention, particularly pain assessments as there is evidence that exposure to acute pain makes individuals more likely to report increasing pain over time even in the absence of a painful stimulus.10 Gender has been highlighted as a potential difference that may contribute to the experience of pain.11 In the present study there was no statistically significant difference in the experiences of post-procedural pain between men and women (pZ0.256). Many patients who have undergone interventional radiology do not experience pain until several hours after their procedure, with pain generally peaking between 6 and 10 h. Consequently, as reported in surgical publications,12,13 patients should be advised to take regular analgesia for the
Patterns, incidence and predictive factors for pain after interventional radiology
Figure 3
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A flowchart demonstrating possible improvements to post-procedural pain management.
24-h period post-procedure in order to pre-empt this situation. There are growing reports in the literature documenting the association between pain and anxiety.14,15 In this report we did not assess the relationship between pre-procedural anxiety and post-procedural pain. In hindsight this is could be used as a predictive factor, and it is our intention to evaluate this factor further. Other potential factors for pain have been identified. Hatsiopoulou and colleagues4 described the association between pain and cognitive factors, e.g. previous medical experiences. According to the Audit Commission12 careful understanding of the factors that can add to the experience of pain and discomfort could potentially reduce the patient’s experience of pain. In a study of day-case surgical patients, the commission reported that effective pain management is not achieved because (a) inadequate analgesia is prescribed, (b) patients do not report pain, (c) health professionals underestimate the patient’s perception of pain, (d) there are delays in the administration of analgesia and (e) pain is not monitored.12 Many of the aspects identified by the Audit Commission are applicable to interventional radiology, and if applied, could help us to reduce the patient’s experience of pain. Post-procedural pain is common, and the pattern and severity of pain between procedures is variable. Pain control after interventional procedures is often inadequate and improvements in pain management are required. From the present study we can conclude that patients about to undergo a painful interventional
procedure should have pre-procedural analgesia within 6 h before the procedure (Fig. 3). The traditional local anaesthetic lidocaine should be replaced with a longer-acting local anaesthetic for percutaneous procedures. Post-procedural analgesia regimes should be included into integrated care pathways and be prescribed by the radiologist who has an understanding of the expected post-procedural pain.
References 1. Mueller PR, Biswal S, Halpern EF, Kaufman JA, Lee MJ. Interventional radiologic procedures: Patient anxiety, perception of pain, understanding of procedure, and satisfaction with medication—a prospective study. Radiology 2000; 215:684—8. 2. Kennedy PT, Helly IMG, Loan WC, Boyd CS. Conscious sedation and analgesia for routine aortofemoral arteriography: A prospective evaluation. Radiology 2000;216:660—4. 3. Skehan SJ, Malone DE, Buckley N, et al. Sedation and analgesia in adult patients: Evaluation of a staged-dose system based on body weight for use in abdominal interventional radiology. Radiology 2000;216:653—9. 4. Hatsiopoulou O, Cohen RI, Land EV. Postprocedural pain management of interventional radiology patients. J Vasc Interv Radiol 2003;14:1373—85. 5. Flandry F, Hunt JP, Terry GC, Hughston JC. Analysis of subjective knee complaints using visual analogue scale. Am J Sports Med 1991;19:112—8. 6. Harshfield DL, Teplick SK, Brandon JC. Pain control during interventional biliary procedures: Epidural versus i.v. sedation. AJR Am J Roentgenol 1993;161:1057—9. 7. Lee MJ, Mueller PR, Saini S, Hahn PF, Dawson SL. Percutaneous dilatation of benign biliary strictures: Single session therapy with general anaesthesia. AJR Am J Roentgenol 1991;157:1263—6.
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8. Lang EV, Benotsch EG, Fick LJ, et al. Adjunctive nonpharmacological analgesia for invasive medical procedures: A randomised trial. Lancet 2000;355:1486—90. 9. Kennedy PT, Kelly IM, Loan WC, Boyd CD. Conscious sedation and analgesia for routine aortofemoral arteriography. A prospective evaluation. Radiology 2000;216:660—4. 10. Bayer TL, Coverdale JH, Chiang E, Bangs M. The role of prior pain experience and expectancy in psychologically and physically induced pain. Pain 1998;74:327—31. 11. Jakobsen DH, Callesen T, Schouenbord L, Nielsen D, Kehlet H. Convalescence after laparoscopic sterilisation. Int J Ambulatory Surg 2003;10:95—9.
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12. Mitchell M. Pain management in day-case surgery. Nurs Stand 2004;18:33—8. 13. Robaux S, Bouaziz H, Cormet C, Boivin JM, Lefeuvre N, Laxenaire MC. Acute post-operative pain management at home after ambulatory surgery: A French pilot study of general practitioners. Anesth Analg 2002;95:1258—62. 14. Cornwall A. The effect of experimentally induced anxiety on the experience of pressure pain. Pain 1988;35:105—13. 15. Graham L, Conley J. Evaluation of anxiety and fear in adult surgical patients. Nurs Res 1971;20:113—22.
Patterns, incidence and predictive factors for pain after interventional radiology A. Englanda,*, C.L. Tama, D.E. Thackera, A.L. Walkera, A.S. Parkinsona, W. DeMellob, A.J. Bradleya, J.S. Tucka, H.-U. Laaschc, J.S. Butterfielda, R.J. Ashleigha, R.E. Englanda, D.F. Martina,d Departments of aRadiology, bAnaesthesia, South Manchester University Hospitals NHS Trust, Southmoor Road, cRadiology, Christie Hospital NHS Trust, Manchester, and dFaculty of Health, University of Central Lancashire, Preston, UK Received 11 March 2005; accepted 5 May 2005
KEYWORDS Interventional procedures, complications; Interventional procedures, quality assurance; Pain; Analgesia
AIM: To evaluate prospectively the pattern, severity and predictive factors of pain after interventional radiological procedures. MATERIALS AND METHODS: All patients undergoing non-arterial radiological interventional procedures were assessed using a visual-analogue scale (VAS) for pain before and at regular intervals for 24 h after their procedure. RESULTS: One hundred and fifty patients (87 men, mean age 62 years, range 18–92 years) were entered into the study. Significant increases in VAS score occurred 8 h after percutaneous biliary procedures (C47.7 mm, SD 14.9 mm; pZ0.001), 6 h after central venous access and gastrostomy insertion (C23.7 mm, SD 19.5 mm; pZ0.001 and C28.4 mm, SD 9.7 mm; pZ0.007, respectively) and 4 h after oesophageal stenting (C27.8 mm, SD 20.2 mm, pZ0.001). Non-significant increases in VAS pain score were observed after duodenal and colonic stenting (duodenal: C5.13 mm, SD 7.47 mm; pZ0.055, colonic: C23.3 mm, SD 13.10 mm, pZ0.250) at a mean of 5 h (range 4–6 h). Patients reported a significant reduction in pain score for nephrostomy insertion (K28.4 mm, SD 7.11 mm, pZ0.001). Post-procedural analgesia was required in 99 patients (69.2%), 40 (28.0%) requiring opiates. Maximum postprocedural VAS pain score was significantly higher in patients who had no preprocedural analgesia (pZ0.003). CONCLUSION: Post-procedural pain is common and the pattern and severity of pain between procedures is variable. Pain control after interventional procedures is often inadequate, and improvements in pain management are required. Q 2005 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.
Introduction There has been rapid growth of interventional radiology during the past 5–10 years.1 Despite this, there has been little documentation or study about pain after radiological intervention.1–4 As interventional radiological procedures become more
* Guarantor and correspondent: A. England, Department of Radiology, South Manchester University Hospitals NHS Trust, Southmoor Road, Manchester M23 9LT, UK. Tel.: C44 161 2916200; fax: C44 161 2916201. E-mail address: [email protected] (A. England).
invasive, complex and readily available, issues of post-procedural pain management are ever more critical. To our knowledge, the incidence and pattern of pain after interventional radiology has never been evaluated. We undertook a prospective study to assess the incidence and pattern of pain after radiological intervention. An additional objective of the study was to attempt to identify any predictive factors for pain after intervention.
Materials and methods All inpatients and outpatients who underwent
0009-9260/$ - see front matter Q 2005 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved. doi:10.1016/j.crad.2005.05.012
Patterns, incidence and predictive factors for pain after interventional radiology
Table 1
Procedures investigated in the study.
Table 2
Predictive factors analysis.
Procedure
Predictive factor
Percutaneous biliary procedures (PTC)a Oesophageal stenting Oesophageal dilatation Duodenal stenting Colonic stenting Percutaneous gastrostomy Central venous access Percutaneous nephrostomy (PCN) Ureteric stenting Liver biopsy
Gender Age ASA grade Pre-procedural analgesia (!6 h) Type of pre-procedural analgesia Pre-procedural VAS pain score Procedure type Intra-procedural fentanyl consumption Intra-procedural midazolam consumption Operator Procedure time Procedure difficulty Post-procedural analgesia Type of post-procedural analgesia
a PTC includes percutaneous biliary drainage and stenting procedures.
interventional radiological procedures from October 2003 to June 2004 were asked to participate in the study. Patients were excluded from the study if (a) they were younger than 18 years; (b) they were unable to understand the nature of the study or complete the data collection sheet. Only patients who were referred for non-arterial radiological intervention were included in the study. Patients referred for vascular arterial intervention were excluded for logistical reasons. Non-arterial interventional procedures are listed in Table 1. The survey was conducted by three of the authors; the individual performing the interviews was not involved in any of the interventional radiological procedures. Potential patients were identified on arrival in the interventional radiology department. The study was then explained to the patient and if they agreed the patient was interviewed before the procedure. The visual analogue scale (VAS) format was used to measure the subjective feeling of pain both before and after the procedure. For this, each patient was given a data collection form, which contained the VAS pain scale. They subjectively assessed their feeling of pre-procedural pain and marked this accordingly on the VAS scale. The options ranged from ‘No pain’ to ‘Worst pain ever’. The patient was then counselled as to the requirements of the study after the procedure, which included a description of the VAS process to be completed on the ward or at home. Patients were asked to quantify their feeling of pain at 2, 4, 6, 8, 12, 16, 20 and 24 h after the procedure using the VAS pain scale. All of the VAS pain scales were given to the patient to take back to the ward or home for selfcompletion. The parameters investigated pre-, intra- and post-procedure are listed in Table 2. Each performing interventional radiologist was graded according to their skill level (consultant or specialist registrar
1189
in training). Survey interviews with patients took place at least 30 min before the procedure. Postprocedural data collection forms were collected 24 h after the procedure. At this point any history of analgesia consumption or adverse event was recorded. If the patient was at home, the patient completed the data collection sheet and returned it to the interventional radiology department in a prepaid envelope. The study was undertaken as an audit with no alteration to clinical practice and as such formal local ethics committee approval was not sought. All patients included agreed to complete the questionnaire and were fully aware of the nature and requirements of the investigation.
Analysis of data Data acquired from the VAS pain questionnaires was taken as a length measurement (mm) using a ruler. All data were then entered into SPSS 11.01 (SPSS, Chicago, IL, USA). Data analysis was performed with the Student’s t-test or an analogous non-parameteric test where appropriate. The level of statistical significance was set at 0.05. The patients were grouped according to their procedure. Pre-procedural VAS pain scores were then compared with the maximum VAS pain scores during the 24-h data collection period. Data were analysed to assess for significant changes in postprocedural pain score. Patients were also grouped into a pain or no-pain category depending on the difference between their pre-procedural pain score and maximum VAS post-procedure pain score. We considered a change of C10.0 mm to represent an increase in pain post-procedure. Variables described in Table 2 were then analysed for their effect on post-procedural pain.
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Sedoanalgesic regime For percutaneous procedures all patients received local skin anaesthetic of 5–10 ml of 1% lidocaine. Tunnelled central venous access was the only exception, patients in this group had lidocaine 1% with adrenaline 1 in 200,000 units (Xylocaine; Astra Zeneca, UK). Depending on the type of procedure and peri-procedural pain different levels of intravenous sedation and analgesia were used. At our institution the drugs used for conscious sedation are midazolam (Hypnovel; Roche Products Ltd, UK) and fentanyl (Sublimaze; Janssen-Cilag, UK). The exact sedoanalgesic regimes used for the study group are listed in Table 3.
Figure 1 A whisker and bar graph to showing the intensity of pain before the interventional radiological procedure.
Pre-procedural analgesia consumption
Results A total of 150 patients who fitted the selection criteria participated in the study. The mean age of the study group was 62 years (range 18–92 years); 87 (57.0%) were men. Twenty-seven patients (18.0%) were ASA grade 1, 87 (58.0%) were grade 2 and the remaining 36 (24.0%) patients were ASA grade 3. There was no patient included in the study with ASA grades 4 or 5.
Pre-procedural pain Inspection of the pre-procedural VAS scores indicated that 88 (58.7%) patients reported pain R10.0 mm. Of the 88 patients, 43 (28.7%) had pre-procedural VAS pain scores R30.0 mm. The pre-procedural VAS scores are graphically described in Fig. 1. The mean pre-procedural VAS pain scores for each procedural group are listed in Table 3. Nephrostomy patients had the highest median preprocedural VAS score (C34.3 mm SD 27.4 mm). Table 3
Seventy-nine (52.7%) of the patients arrived in the interventional department having been administered analgesia within 6 h. Of these patients, 50 (63.3%) patients had non-opiate and 29 (36.7%) patient had opiate analgesia. Of the patients with no pre-procedural pain (nZ62), 21 (33.9%) patients had received analgesia with 6 h.
Post-procedural pain Significant increases in VAS score occurred 8 h after percutaneous biliary procedures (C47.7 mm, SD 14.9 mm; pZ0.001), 6 h after central venous access and gastrostomy insertion (C23.7 mm, SD 19.5 mm; pZ0.001 and C28.4 mm, SD 9.7 mm; pZ 0.007, respectively) and 4 h after oesophageal stenting (C27.8 mm, SD 20.2 mm, pZ0.001). Non-significant increases in VAS pain score were observed after duodenal and colonic stenting (duodenal: C5.13 mm, SD 7.47 mm; pZ0.055, colonic: C23.3 mm, SD 13.10 mm, pZ0.250) at a
Summary of pre-procedural VAS pain score and procedural parameters.
Procedure
n
Procedure time (min)
Procedural
Pre-VAS scores (mm)
Mean
Range
Sedation
IV analgesia
Mean
SD
PTC Oesophageal stenting Duodenal stenting Colonic stenting Gastrostomy Oesophageal dilatation Central venous access Nephrostomy Liver biopsy Ureteric stenting
14 38 9 3 15 12 23 23 10 3
45.7 30.1 39.4 40.0 40.0 32.1 34.3 43.6 15.0 63.3
25–75 15–60 20–60 30–45 25–120 20–40 30–60 20–90 10–20 40–90
14 (100%) 38 (100%) 9 (100%) 3 (100%) 15 (100%) 12 (100%) 23 (100%) 19 (83%) 0 (0%) 1 (33%)
12 (86%) 38 (100%) 9 (100%) 3 (100%) 15 (100%) 12 (100%) 1 (4%) 22 (96%) 0 (0%) 1 (33%)
15.4 20.5 21.1 13.3 10.1 13.3 16.7 34.4 16.0 10.0
16.7 19.9 37.5 23.1 9.8 23.1 18.7 27.4 32.0 17.3
Patterns, incidence and predictive factors for pain after interventional radiology
Table 4
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Post-procedural changes in VAS pain score.
Procedure
PTC Oesophageal stent Duodenal stent Colonic stent Gastrostomy Oesophageal dilatation Nephrostomy Central venous access Ureteric stent Liver biopsy
n
14 38 9 3 15 12 23 23 3 10
Maximum visual analogue pain score
p-Value
Mean (mm)
SD (mm)
Peak time
47.7 27.8 5.13 23.3 28.4 5.8 K28.4 23.7 16.6 15.0
14.9 20.2 7.47 13.10 9.7 22.0 7.11 19.5 5.7 49.5
8 4 8–12 6 6–8 2 24 6 2 8
mean of 5 h (range 4–6 h). Patients reported a significant reduction in pain score for nephrostomy insertion (K28.4 mm, SD 7.11 mm, pZ0.001). Postprocedural VAS pain scores are listed in Table 4, pain patterns after interventional radiological procedures are displayed graphically in Figs. 2 (a–d). Postprocedural analgesia was required in 99 patients (69.2%), 40 (28.0%) required opiates.
Predictive factor analysis Pre-procedural VAS pain score and pre-procedural
0.001 0.001 0.055 0.250 0.007 0.377 0.001 0.001 0.363 0.105
analgesia were the only two statistically significant factors identified in the analysis. Patients who had no pain before the interventional radiological procedure had significantly greater increases in their pain score post-procedure (pZ0.001). Also, patients who received no pre-procedural analgesia had significantly higher post-procedural pain when compared with patients who had pain relief within 6 h before the procedure (PZ0.04). This association is linear, patients who have moderate analgesia had less risk of getting pain postprocedure when compared with the mild analgesia
Figures 2 (a–d) Line graphs showing the individual patterns and intensities of pain after specific radiological interventional procedures.
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Table 5 Predictive factors for pain following radiological intervention. Variable
Group Pain
p-Value No-pain
Age, years 61.6 SD 16.0 62.2 SD 14.5 Gender, M:F 48:29 39:24 ASA grade I 14 13 II 50 37 II 23 13 Pre-procedure 12.3 SD 15.8 29.0 SD 27.8 VAS, mm Procedure 36.2 SD 17.1 35.1 SD 16.2 time, min Fentanyl, mg* 73.8 76.1 Midazolam, 68.1 80.8 mg* Operator Trainee 51 39 Consultant 36 24 Pre-procedure analgesia consumption None 47 24 Mild 20 15 Moderate 6 9 Strong 14 15 Post-procedure analgesia consumption None 23 25 Mild 29 17 Moderate 7 7 Strong 28 14
0.457 0.256 0.334
0.001 0.406 0.676 0.073
0.407
0.04
0.128
group. A full detailed list of the predictive factors analysed is summarized in Table 5.
Discussion Despite the growth and interest in interventional radiology in recent years there are limited studies on pain associated with interventional procedures. We have performed a prospective study investigating the issue of pain after intervention. To quantify the patient’s experience of pain after radiological intervention we used the VAS pain scale. Although this method is not perfect, it is a common way to assess pain.1,5 From the preprocedural interview it was apparent that there was a wide range in the levels of pain experienced by patients arriving in the department. Furthermore, there is a wide range in the prescribing practices for patients attending the interventional radiology department. The present results are in keeping with other published studies highlighting percutaneous biliary procedures as amongst the most painful interventional radiological procedures. 3,6,7 Studies by Harshfield et al.6 and Lee et al.,7 advocate the
use of epidural and general anaesthesia in certain biliary procedures to reduce pain. Lidocaine is the most commonly used local anaesthetic currently in use.4 Despite is wide use in interventional radiology the duration of action rarely exceeds 2 h. Suggestions have been made regarding the combined use of longer-acting local anaesthetics, e.g. ropivacaine hydrochloride (Naropin; Astra Zeneca, UK).4 Combined use of short and long-acting local anaesthetic may have particular benefit in percutaneous interventional procedures where peak pain times are 6–8 h, well beyond the range of lidocaine. Some use premedication as a method of sedoanalgesia as an adjunct to intra-procedural analgesia and sedation.4 In the present study, patients who had pre-procedural analgesia were less likely to get increases in postprocedural pain (pZ0.04). Data from the present study supports the administration of pre-procedural analgesia as a method of reducing post-procedural pain. If lengthy post-procedural pain is anticipated early involvement of the hospital-based ‘Acute Pain Service’ is advisable as the team has access to an entire spectrum of conventional and integrative modes of pain management.4 Procedure duration has previously been identified as a critical parameter in the pain experience.8 A study of abdominal interventional procedures confirmed that patients reporting greater pain had technically more difficult procedures and more time-intensive procedures.9 In the present study there was no statistical significance when comparing pain with procedure length (pZ0.406). Two reasons can be suggested for this: (a) the majority of patients had procedures of the same duration and complexity; or (b) the lengthy procedures were for patients with pre-procedural pain and there were existing pathways in place for dealing with post-procedural pain. Patients who have had lengthy procedures may require close attention, particularly pain assessments as there is evidence that exposure to acute pain makes individuals more likely to report increasing pain over time even in the absence of a painful stimulus.10 Gender has been highlighted as a potential difference that may contribute to the experience of pain.11 In the present study there was no statistically significant difference in the experiences of post-procedural pain between men and women (pZ0.256). Many patients who have undergone interventional radiology do not experience pain until several hours after their procedure, with pain generally peaking between 6 and 10 h. Consequently, as reported in surgical publications,12,13 patients should be advised to take regular analgesia for the
Patterns, incidence and predictive factors for pain after interventional radiology
Figure 3
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A flowchart demonstrating possible improvements to post-procedural pain management.
24-h period post-procedure in order to pre-empt this situation. There are growing reports in the literature documenting the association between pain and anxiety.14,15 In this report we did not assess the relationship between pre-procedural anxiety and post-procedural pain. In hindsight this is could be used as a predictive factor, and it is our intention to evaluate this factor further. Other potential factors for pain have been identified. Hatsiopoulou and colleagues4 described the association between pain and cognitive factors, e.g. previous medical experiences. According to the Audit Commission12 careful understanding of the factors that can add to the experience of pain and discomfort could potentially reduce the patient’s experience of pain. In a study of day-case surgical patients, the commission reported that effective pain management is not achieved because (a) inadequate analgesia is prescribed, (b) patients do not report pain, (c) health professionals underestimate the patient’s perception of pain, (d) there are delays in the administration of analgesia and (e) pain is not monitored.12 Many of the aspects identified by the Audit Commission are applicable to interventional radiology, and if applied, could help us to reduce the patient’s experience of pain. Post-procedural pain is common, and the pattern and severity of pain between procedures is variable. Pain control after interventional procedures is often inadequate and improvements in pain management are required. From the present study we can conclude that patients about to undergo a painful interventional
procedure should have pre-procedural analgesia within 6 h before the procedure (Fig. 3). The traditional local anaesthetic lidocaine should be replaced with a longer-acting local anaesthetic for percutaneous procedures. Post-procedural analgesia regimes should be included into integrated care pathways and be prescribed by the radiologist who has an understanding of the expected post-procedural pain.
References 1. Mueller PR, Biswal S, Halpern EF, Kaufman JA, Lee MJ. Interventional radiologic procedures: Patient anxiety, perception of pain, understanding of procedure, and satisfaction with medication—a prospective study. Radiology 2000; 215:684—8. 2. Kennedy PT, Helly IMG, Loan WC, Boyd CS. Conscious sedation and analgesia for routine aortofemoral arteriography: A prospective evaluation. Radiology 2000;216:660—4. 3. Skehan SJ, Malone DE, Buckley N, et al. Sedation and analgesia in adult patients: Evaluation of a staged-dose system based on body weight for use in abdominal interventional radiology. Radiology 2000;216:653—9. 4. Hatsiopoulou O, Cohen RI, Land EV. Postprocedural pain management of interventional radiology patients. J Vasc Interv Radiol 2003;14:1373—85. 5. Flandry F, Hunt JP, Terry GC, Hughston JC. Analysis of subjective knee complaints using visual analogue scale. Am J Sports Med 1991;19:112—8. 6. Harshfield DL, Teplick SK, Brandon JC. Pain control during interventional biliary procedures: Epidural versus i.v. sedation. AJR Am J Roentgenol 1993;161:1057—9. 7. Lee MJ, Mueller PR, Saini S, Hahn PF, Dawson SL. Percutaneous dilatation of benign biliary strictures: Single session therapy with general anaesthesia. AJR Am J Roentgenol 1991;157:1263—6.
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8. Lang EV, Benotsch EG, Fick LJ, et al. Adjunctive nonpharmacological analgesia for invasive medical procedures: A randomised trial. Lancet 2000;355:1486—90. 9. Kennedy PT, Kelly IM, Loan WC, Boyd CD. Conscious sedation and analgesia for routine aortofemoral arteriography. A prospective evaluation. Radiology 2000;216:660—4. 10. Bayer TL, Coverdale JH, Chiang E, Bangs M. The role of prior pain experience and expectancy in psychologically and physically induced pain. Pain 1998;74:327—31. 11. Jakobsen DH, Callesen T, Schouenbord L, Nielsen D, Kehlet H. Convalescence after laparoscopic sterilisation. Int J Ambulatory Surg 2003;10:95—9.
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12. Mitchell M. Pain management in day-case surgery. Nurs Stand 2004;18:33—8. 13. Robaux S, Bouaziz H, Cormet C, Boivin JM, Lefeuvre N, Laxenaire MC. Acute post-operative pain management at home after ambulatory surgery: A French pilot study of general practitioners. Anesth Analg 2002;95:1258—62. 14. Cornwall A. The effect of experimentally induced anxiety on the experience of pressure pain. Pain 1988;35:105—13. 15. Graham L, Conley J. Evaluation of anxiety and fear in adult surgical patients. Nurs Res 1971;20:113—22.