Cost Effectiveness of Endovascular Revascularisation vs. Exercise Therapy for Intermittent Claudication Due to Iliac Artery Obstruction.

OBJECTIVE: To compare cost effectiveness of endovascular revascularisation (ER) and supervised exercise therapy (SET) as primary treatment for patients with intermittent claudication (IC) due to iliac artery obstruction. METHODS: Cost utility analysis from a restricted societal perspective and time horizon of 12 months. Patients were included in a multicentre randomised controlled trial (SUPER study, NCT01385774, NTR2648) which compared effectiveness of ER and SET. Health status and health related quality of life (HRQOL) were measured using the Euroqol 5 dimensions 3 levels (EQ5D-3L) and VascuQol-25-NL. Incremental costs were determined per allocated treatment and use of healthcare during follow up. Effectiveness of treatment was determined in quality adjusted life years (QALYs). The difference between treatment groups was calculated by an incremental cost utility ratio (ICER). RESULTS: Some 240 patients were included, and complete follow up was available for 206 patients (ER 111 , SET 95). The mean costs for patients allocated to ER were €4 031 and €2 179 for SET, a mean difference of €1 852 (95% bias corrected and accelerated [bca] bootstrap confidence interval 1 185 - 2 646). The difference in QALYs during follow up was 0.09 (95% bcaCI 0.04 - 0.13) in favour of ER. The ICER per QALY was €20 805 (95% bcaCI 11 053 - 45 561). The difference in VascuQol sumscore was 0.64 (95% bcaCI 0.39 - 0.91), again in favour of ER. CONCLUSION: ER as a primary treatment, results in slightly better health outcome and higher QALYs and HRQOL during 12 months of follow up. Although these differences are statistically significant, clinical relevance must be discussed due to the small differences and relatively high cost of ER as primary treatment.

Editor's Choice - Randomised Clinical Trial of Supervised Exercise Therapy vs. Endovascular Revascularisation for Intermittent Claudication Caused by Iliac Artery Obstruction: The SUPER study.

OBJECTIVE: International guidelines recommend supervised exercise therapy (SET) as primary treatment for all patients with intermittent claudication (IC), yet primary endovascular revascularisation (ER) might be more effective in patients with iliac artery obstruction. METHODS: This was a multicentre RCT including patients with IC caused by iliac artery stenosis or occlusion (NCT01385774). Patients were allocated randomly to SET or ER stratified for maximum walking distance (MWD) and concomitant SFA disease. Primary endpoints were MWD on a treadmill (3.2 km/h, 10% incline) and disease specific quality of life (VascuQol) after one year. Additional interventions during a mean follow up of 5.5 years were recorded. RESULTS: Between November 2010 and May 2015, 114 patients were allocated to SET, and 126 to ER. The trial was terminated prematurely after 240 patients were included. Compliance with SET was 57/114 (50%) after six months. Ten patients allocated to ER (8%) did not receive this intervention. One year follow up was complete for 90/114 (79%) SET patients and for 104/126 (83%) ER patients. The mean MWD improved from 187 to 561 m in SET patients and from 196 to 574 m in ER patients (p = .69). VascuQol sumscore improved from 4.24 to 5.58 in SET patients, and from 4.28 to 5.88 in ER patients (p = .048). Some 33/114 (29%) SET patients had an ER within one year, and 2/114 (2%) surgical revascularisation (SR). Some 10/126 (8%) ER patients had additional ER within one year and 10/126 (8%) SR. After a mean of 5.5 years, 49% of SET patients and 27% of ER patients underwent an additional intervention for IC. CONCLUSION: Taking into account the many limitations of the SUPER study, both a strategy of primary SET and primary ER improve MWD on a treadmill and disease specific Qol of patients with IC caused by an iliac artery obstruction. It seems reasonable to start with SET in these patients and accept a 30% failure rate, which, of course, must be discussed with the patient. Patients continue to have interventions beyond one year.

Diagnostic potential of plasma biomarkers and exhaled volatile organic compounds in predicting the different stages of acute mesenteric ischaemia: protocol for a multicentre prospective observational study (TACTIC study).

INTRODUCTION: Acute mesenteric ischaemia (AMI) is a life-threatening condition with short-term mortality of up to 80%. The diagnosis of AMI has remained troublesome due to the non-specific clinical presentation, symptoms and laboratory findings. Early unambiguous diagnosis of AMI is critical to prevent progression from reversible to irreversible transmural intestinal damage, thereby decreasing morbidity and improving survival. The present study aims to validate a panel of plasma biomarkers and investigate volatile organic compound (VOC) profiles in exhaled air as a tool to timely and accurately diagnose AMI. METHODS AND ANALYSIS: In this international multicentre prospective observational study, 120 patients (>18 years of age) will be recruited with clinical suspicion of AMI. Clinical suspicion is based on: (1) clinical manifestation, (2) physical examination, (3) laboratory measurements and (4) the physician's consideration to perform a CT scan. The patient's characteristics, repetitive blood samples and exhaled air will be prospectively collected. Plasma levels of mucosal damage markers intestinal fatty acid-binding protein and villin-1, as well as transmural damage marker smooth muscle protein 22-alpha, will be assessed by ELISA. Analysis of VOCs in exhaled air will be performed by gas chromatography time-of-flight mass spectrometry. Diagnosis of AMI will be based on CT, endovascular and surgical reports, clinical findings, and (if applicable) verified by histopathological examination. ETHICS AND DISSEMINATION: The study protocol was approved by the Medical Research Ethics Committee (METC) of Maastricht University Medical Centre+ and Maastricht University (METC azM/UM), the Netherlands (METC19-010) and the Ethics Committee Research UZ/KU Leuven, Belgium (S63500). Executive boards and local METCs of other Dutch participating centres Gelre Ziekenhuizen (Apeldoorn), Medisch Spectrum Twente (Enschede), and University Medical Centre Groningen have granted permission to carry out this study. Study results will be disseminated via open-access peer-reviewed scientific journals and national/international conferences. TRIAL REGISTRATION NUMBER: NCT05194527.

Chronic pancreatitis patients show hyperalgesia of central origin: a pilot study.

BACKGROUND: The pain of chronic pancreatitis remains challenging to manage, with treatment all too often being unsuccessful. A main reason for this is lacking understanding of underlying mechanisms of chronic pain in these patients. AIM: To document, using somatic quantitative sensory testing, changes in central nervous system processing (neuroplasticity) associated with chronic pancreatitis pain and thus gain insight into underlying pain mechanisms. PATIENTS AND METHODS: We studied 10 chronic pancreatitis patients on stable opioid analgesic medication. Ten matched surgical patients without pain served as controls. Pain verbal numeric rating scores (NRS) and thresholds to electric skin stimulation and pressure pain were measured in dermatomes T10 (pancreatic area), C5, T4, L1 and L4. RESULTS: The pancreatitis patients had a median NRS pain score of 5 (range 3-8). Electric sensation and pain thresholds were significantly increased in the pancreatic region, tending to be more so in female pancreatitis patients. Pressure pain thresholds were significantly lower in pancreatitis patients than in controls, with men tending towards greater generalised relative hyperalgesia than women. CONCLUSIONS: Chronic pancreatitis patients show pronounced generalised deep hyperalgesia that is present despite opioid therapy. These signs, consistent with central sensitisation, appear relatively more prominent in men than women. There is also evidence suggesting that women may have a better segmental inhibitory response than men, possibly explaining their relatively less prominent generalised deep tissue hyperalgesia compared to men.

Has central sensitization become independent of nociceptive input in chronic pancreatitis patients who fail thoracoscopic splanchnicectomy?

BACKGROUND AND OBJECTIVES: Central sensitization due to visceral pancreatic nociceptive input may be important in chronic pancreatitis pain. We investigated whether bilateral thoracoscopic splanchnicectomy (BTS) to reduce nociceptive input in chronic pancreatitis patients (CPP) with poor pain control affects supraspinal and spinal sensitization. METHODS: Seventeen CPP were studied preoperatively and 6 weeks after BTS. Pressure pain thresholds (PPT) were measured in clavicle and pancreatic dermatomes reflecting supraspinal and spinal central sensitization, respectively. Patients with increased PPT after BTS (hypoalgesic) were compared to those without (hyperalgesic) and PPT vs. pain numeric rating scale (NRS) changes compared. RESULTS: After BTS, ten patients showed C5 PPT increases (hypoalgesic; median change 87 kPa), 7 patients had unaltered/lower PPT (hyperalgesic; -135 kPa). Preoperative pain NRS was similar between groups (4 vs. 5, P = 0.2). After BTS hypoalgesic group NRS was lower (1 vs. 6; P = 0.008) and NRS change greater (-2 vs. 0; P = 0.005). Whole group NRS and C5 PPT change correlated significantly and negatively (r = 0.53; P < 0.05), but not for pancreatic PPT. CONCLUSIONS: Reduced supraspinal-but not spinal-central sensitization after BTS was associated with significantly reduced pain scores in a majority of CPP. A subgroup showed no reductions in supraspinal central sensitization after BTS, coupled to no significant pain NRS reduction. Our results suggest that a subgroup of CPP has altered pain processing that may be independent of ongoing peripheral nociceptive input, resulting in persisting pain despite BTS. If confirmed, these results indicate the importance of sensory testing for indications and management of pain treatments.

S-ketamine modulates hyperalgesia in patients with chronic pancreatitis pain.

BACKGROUND AND OBJECTIVES: Upper abdominal pain is a dominant feature of chronic pancreatitis. A key phenomenon in this context is hyperalgesia, typically associated with N-methyl-d-aspartate receptor activation. This exploratory study evaluates acute effects of S-ketamine, a noncompetitive N-methyl-d-aspartate antagonist, in modulating generalized hyperalgesia in chronic pancreatitis pain. METHODS: In a blinded crossover trial, 10 chronic pancreatitis pain patients received S-ketamine for 3 hrs at 2 µg · kg · min or placebo infusion at an equivalent rate in randomized order. Clinical pain was assessed via visual analog scale (VAS) and short Dutch Language Version McGill Pain Questionnaire (sf-MPQ-DLV). Pressure pain thresholds (PPTs) were measured in dermatome C5, T4, dorsal T10, L1, and L4, and the sum of PPTs (SOPPT) calculated before, at end of, and after infusion. RESULTS: Nine patients completed the study. Median pain VAS before infusion was 29 mm at rest, 32 mm during activity; sf-MPQ-DLV score was 4. For the S-ketamine session median SOPPT change at infusion end was significantly higher than in the placebo session (218; interquartile range [IQR], 116-527, versus -123 [IQR, -330 to 24]; P = 0.005) and significant versus preinfusion values (2109 [IQR, 964-3035] vs 1914 [IQR, 842-2884]; P = 0.03). The SOPPT was unchanged versus preinfusion values and similar between groups at 1 hr after infusion end. No significant changes in VAS and sf-MPQ-DLV occurred. CONCLUSIONS: S-ketamine infusion is more effective than placebo in increasing PPTs in chronic pancreatitis pain patients immediately after infusion. This effect did not outlast the infusion. Further research is warranted into S-ketamine use for reducing generalized hyperalgesia and chronic pancreatitis pain.

Limited effect of thoracoscopic splanchnicectomy in the treatment of severe chronic pancreatitis pain: a prospective long-term analysis of 75 cases.

BACKGROUND: Bilateral thoracoscopic splanchnicectomy is a minimally invasive method of treating pain in patients with chronic pancreatitis. It offers good, short-term pain relief, but long-term success is difficult to predict. We analyze long-term results and identify factors predicting success of splanchnicectomy. METHODS: A total of 75 consecutive chronic pancreatitis patients underwent bilateral thoracoscopic splanchnicectomy with long term follow-up (>or=1 year). Treatment success was analyzed using the Kaplan-Meier method, and possible predictive factors (etiology, gender, onset of pancreatitis, previous pancreatitis-related surgery, opioid use, pathology at imaging, technical success, and post-splanchnicectomy complications) via the Cox proportional hazards regression model. We compared patients with long-term pain relief, patients who failed the procedure within 1 year, and those who had pain recurrence after > 1 year. Further treatments after failed splanchnicectomy were evaluated. RESULTS: A total of 66 patients (88%) were on continuous opioids; 47 (63%) had prior pancreatitis-related interventions. Treatment was successful in 52% of patients at 12 months, 38% at 24 months, and 28% at 48 months. At the end of follow-up, 21 patients (28%) reported pain relief, of whom 13 were completely pain free without any additional treatment. Pancreatic surgery after failed splanchnicectomy relieved pain in only 13% of patients. Technical success was the only independent factor significantly associated with successful splanchnicectomy outcome (P = .03). Preoperative opioid use showed a strong tendency to be associated with unsuccessful outcome (P = .07). CONCLUSION: Splanchnicectomy offers prolonged (>4 years) benefit in 1 of 4 patients with severe chronic pancreatitis pain. Prior opioid use may adversely impact pain relief after splanchnicectomy.