Chronic outpatient treatment with topical sevoflurane in patients with vascular ulcers

OBJECTIVE

To show the effectiveness and safety of topical sevoflurane after ambulatory and prolonged administration in patients with refractory vascular ulcers.

METHODS

Retrospective observational study analyzing clinical improvement and vascular ulcers surface area variation after topical application of sevoflurane. Inclusion criteria were patients with painful vascular ulcers refractory to usual therapies and who were treated with topical sevoflurane for at least 36 months. The following variables were collected: age, sex, medical history, associated comorbidity, ulcer etiology and medical treatment. The visual analog scale was used to measure baseline and break through pain intensity before and after treatment.

RESULTS

Nine patients met the inclusion criteria of the total number of patients treated whose median age was 74.8 ± 7.5 years. Cases 2 and 9 died during follow-up. In all cases, the analgesic action of topical sevoflurane was rapid (3.1 ± 2.1 minutes), intense (visual analog scale: 7 ± 1.1 to 1.4 ± 1.1 points) and long-lasting (6 to 24 h). With the exception of case 4, all patients experienced a large reduction in vascular ulcers surface area (15.1 ± 5.0 a 2.7 ± 4.2) and tolerance was not observed over time.

CONCLUSION

Topical application of sevoflurane is an analgesic and re-epithelializing strategy for vascular ulcers with a successful safety profile.

At-home Topical Sevoflurane Added to the Conventional Analgesic Treatment for Painful leg Ulcers Greatly Improved the Analgesic Effectiveness and Reduced Opioid Consumption in a Single-Center Retrospective Comparative Study with one-Year Follow-up

The general anesthetic sevoflurane is being repurposed as a topical analgesic for painful chronic wounds. This study was aimed to compare the analgesic effectiveness and safety of systemic analgesics alone or plus at-home topical sevoflurane for the management of patients with painful nonrevascularizable leg ulcers who were referred to a Pain Clinic by their attending vascular surgeons. We reviewed charts of patients treated in a single Pain Clinic with analgesic Standard of Care either alone (group SoC) or plus at-home topical sevoflurane (group SoC + Sevo), according to safety criteria. The area under the curve of pain over a year (AUC-Pain) was the primary outcome for analgesic effectiveness. Opioids were converted into Oral Morphine Milligram Equivalents. Groups SoC (n = 26) and SoC + Sevo (n = 38) were similar in baseline characteristics. Compared to SoC, median values [interquartile range] of area under the curve of pain for one-year follow-up were markedly lower for SoC + Sevo (54 [35-65] vs. 15 [11-23]; p < 0.000001, U Mann-Whitney test). Oral Morphine Milligram Equivalents were similar at baseline (SoC: 78.5 [22.5-135] vs. SoC + Sevo: 101.3 [30-160]; p = 0.753), but significantly lower for SoC + Sevo at three (120 [22.5-202.5] vs. 30 [0-80]; p = 0.005), six (120 [11.3-160] vs. 20 [0-67.5]; p = 0.004), nine (114.4 [0-154] vs. 0 [0-37]; p = 0.018), and 12 months (114.4 [0-154] vs. 0 [0-20]; p = 0.001). Multiple linear regression analysis revealed the addition of sevoflurane to be the most likely variable to explain this difference in outcome (ß:-33.408; p < 0.000001). Nine patients (24%) in SoC + Sevo had adverse effects attributed to sevoflurane, but only one patient needed to stop using sevoflurane due severe dermatitis. In conclusion, the addition of topical sevoflurane to the analgesic standard of care in patients with painful nonrevascularizable leg ulcers was a well-tolerated therapy that significantly improved pain control and allowed for a significant reduction in opioid consumption.

Cost-effectiveness analysis of domiciliary topical sevoflurane for painful leg ulcers

Objectives

The general anesthetic sevoflurane is being repurposed as a topical analgesic for painful chronic wounds. We conducted a Bayesian cost-effectiveness analysis (CEA) comparing the addition of domiciliary topical sevoflurane to conventional analgesics (SEVOFLURANE, n = 38) versus conventional analgesics alone (CONVENTIONAL, n = 26) for the treatment of nonrevascularizable painful leg ulcers in an outpatient Pain Clinic of a Spanish tertiary hospital.

Methods

We used real-world data collected from charts to conduct this CEA from a public healthcare perspective and with a one-year time horizon. Costs of analgesics, visits and admissions were considered, expressed in €2016. Analgesic effectiveness was measured with SPID (Sum of Pain Intensity Difference). A Bayesian regression model was constructed, including “treatment” and baseline characteristics for patients (“arterial hypertension”) and ulcers (“duration”, “number”, “depth”, “pain”) as covariates. The findings were summarized as a cost-effectiveness plane and a cost-effectiveness acceptability curve. One-way sensitivity analyses, a re-analysis excluding those patients who died or suffered from leg amputation, and an extreme scenario analysis were conducted to reduce uncertainty.

Results

Compared to CONVENTIONAL, SEVOFLURANE was associated with a 46% reduction in costs, and the mean incremental effectiveness (28.15±3.70 effectiveness units) was favorable to SEVOFLURANE. The estimated probability for SEVOFLURANE being dominant was 99%. The regression model showed that costs were barely influenced by any covariate, whereas effectiveness was noticeably influenced by “treatment”. All sensitivity analyses showed the robustness of the model, even in the extreme scenario analysis against SEVOFLURANE.

Conclusions

SEVOFLURANE was dominant over CONVENTIONAL as it was less expensive and much more effective.

Topical sevofluran: a galenic experience

Sevoflurane is a volatile liquid from the family of ether-derived alogenated hydrocarbons that is approved for the induction and  maintenance of inhalational general anesthesia in the hospital setting. This review describes the pioneering experience of a Spanish Pain Unit in the  home treatment of complicated painful wounds using topical sevoflurane  instillations according to a protocol approved for off-label use. Aspects of  safety and efficacy, both analgesic, antimicrobial and pro-healing are  addressed, and some future lines of research are discussed in terms of  new formulations for topical use. After more than seven years of use of the protocol, an experience of over 70,000 applications of topical sevoflurane  has been gained. In general terms, the analgesic effect appears quickly, is  highly intense and persists for several hours. As a result, patients can  reduce their consumption of systemic analgesics and benefit from an  improvement in their quality of life. In addition, there are signs that  suggest sevoflurane also possesses antimicrobial and pro-healing  properties. Regarding safety, pruritus at the level of the periulcerous skin  is the most frequently reported adverse effect, although it is usually  transient and well-tolerated, and no systemic toxicity has been reported.  Overall, the risk-benefit balance of the drug has so far been very  favorable. To avoid manipulation of this volatile liquid, we have developed  a new formulation of sevoflurane in gel form, which has made it possible  to successfully apply sevoflurane in the context of painful pathologies  where the skin remains intact. Furthermore, these types of new  formulations, including sevoflurane microspheres, which we have also  developed, could improve the efficacy and safety of topical sevoflurane  while reducing the occupational exposure of healthcare staff. This means  that the development of new formulations is a field with a very promising  future.

Sevoflurane topical analgesia for intractable pain with suicidal ideation

Proper symptom management to improve quality of dying is mandatory in palliative care patients. Home-based control of pain caused by leg ulcers is challenging, especially when the pain is severe and refractory to conventional analgesics, the patient is intolerant to opioids and refuses invasive measures. This was the case for an 87-year-old woman under oncological palliative care who suffered from a leg ulcer causing refractory pain, which produced suicidal ideation. Leg amputation was indicated, but she had signed a living will refusing any invasive measures. After obtaining written informed consent, sevoflurane was applied topically on the ulcer, which resulted in a rapid and long-lasting reduction of pain. Daily self-administration of sevoflurane successfully controlled the wound pain and the patient abandoned her suicidal ideation, the wound healed 35 days later, and her quality of dying improved remarkably. Topical sevoflurane deserves further research on ulcers of vascular and also neoplastic aetiology.

Pain reduction of topical sevoflurane vs intravenous opioids in pressure ulcers

Recently, it has been reported that topical irrigations of liquid sevoflurane on the bed of painful wounds produce a rapid, intense, and lasting analgesic effect. In this paper, A cohort of 112 patients with painful pressure ulcers who were refractory to opioids (or who exhibited undesirable adverse events to them) was treated with topical sevoflurane as per local institutional policy. These patients were recruited from an intensive care unit for a period of 3 years. The main aim was to determine the effectiveness of topical sevoflurane in reducing the pain of PUs and reducing the ulcer area. Study findings are reported and discussed herein and suggest that sevoflurane is a viable and promising treatment option for PUs.

Efficacy and safety of topical sevoflurane in the treatment of chronic skin ulcers

PURPOSE

Results of efficacy and safety assessments of topical sevoflurane use in patients with long-term treatment-refractory vascular ulcers are reported.

METHODS

Patients were randomly assigned to receive sevoflurane instillations (1 mL per cm² of ulcer area 1-4 times daily) plus standard wound care (ulcer cleaning, debridement, and dressing changes) or standard care only. Topical sevoflurane was initiated during hospitalization, with self- or nurse-administered instillations continued after discharge. Study participants were evaluated at least once weekly for 1 month and then every 2 weeks for up to 90 days. The primary efficacy measures were debridement-related and overall pain (assessed using a 10-point visual analog scale), daily opioid use, and ulcer size; secondary measures were patient and clinician impressions of improvement and ulcer-related admissions during treatment. The primary safety endpoint was intolerable sevoflurane-related adverse effects.

RESULTS

Compared with the group receiving standard care alone (n = 5), the sevoflurane group (n = 10) had significant (p = 0.001) reductions in mean ± S.D. scores for debridement-related pain on day 1 of treatment and at subsequent time points; the sevoflurane group also had significant reductions in overall pain, daily opioid use, and ulcer size. Outcomes in terms of patient- and clinician-rated improvement and emergency admissions also favored the sevoflurane group. Mild localized reddening in the area surrounding ulcers occurred in 4 sevoflurane-treated patients.

CONCLUSION

Direct application of sevoflurane onto vascular ulcers resulted in an intense and long-lasting analgesia and was associated with a progressive reduction of ulcer size.

Palliative analgesia with topical sevoflurane in cancer-related skin ulcers: a case report

A Caucasian 39-year-old male patient with a poorly-differentiated infiltrating epidermoid penile carcinoma with urethral invasion was diagnosed. The patient received concomitant adjuvant chemotherapy with radiotherapy in the palliative setting, which produced painful ulceration of tumour lesions at loco-regional level (Numerical Rate Scale, NRS=9). The patient consented for treatment with direct topical sevoflurane instillations, at initial doses of 1 mL/cm² of ulcerated area, as per unit protocol. The local use of undiluted sevoflurane achieved a marked reduction of the pain score in both nociceptive and irruptive pains (average NRS=3 immediately post-application). This improvement was corroborated by a decline in total morphine needs, any adverse events associated with major opiates. PGI-I and CGI-I scales were used before and after treatment with topical sevoflurane to assess patient and clinician perceptions of improvement in the quality of life. The pharmacy of our hospital had the responsibility to elaborate pre-loaded syringes with sevoflurane so that the patient was instilled simply and comfortably.