Modified Methods On The Preparation Of Bleomycin Foam For The Treatment Of Venous Malformations And Preliminary Assessment Of Clinical Safety

Background:Venous malformations(VMs)are common disease in the head and neck which can cause deformities,dysfunction,infection,bleeding,and other complications.In recent years,bleomycin foam has been reported to be an effective sclerotherapy method for the treatment of VMs.Objective:This study was aimed to modify the currently used method for preparing bleomycin foam,in order to simplify the preparation procedure,produce foam with greater volume and increased stability and perform clinical study on the safety and efficacyMethods:1.6.0 IU of bleomycin powder was dissolved in different human serum albumin(HSA):saline solution(SS)ratios of 0.5:1.5.0.75:1.25,1:1,1.25:0.75,1.5:0.5,1.75:0.25,and 2:0 in volume;then,an air:liquid ratio of 2:1 was used to create foam using the Tessari’s method.The optimum proportion of HSA:SS was screened by comparing the foam half-life time(FHT)2.6.0 IU of bleomycin was dissolved directly in 2.0 mL of HSA;then,air:liquid ratios of 1:1,2:1,3:1,and 4:1 were used to create foam using the Tessari’s method.The optimum proportion of air:liquid was screened by comparing the FHT.Experimental values were examined and analyzed,using SPSS 19.0 software package,by K-W test and t-test.Results:1.The optimum proportion of HSA:SS was 2:0 and the FHT was 7.48±0.47 min.2.The optimum proportion of air:liquid was 3:1 and the FHT was 9.03±0.59 min.Conclusions:The modified method is simpler and could produce more stable bleomycin foam with greater volume.Background:Bleomycin(BLM)foam sclerotherapy is effective in the treatment of venous malformations(VMs)and the extent of therapeutic effects depends on foaming properties and the stability.The foam stability is influenced by factors such as sclerosant viscosity,sclerosant concentration,different gases,the liquid-gas ratio and production methods.Hyaluronic acid(HA)is widely distributed in all kinds of tissues and intercellular substance,especially in the vitreous and the synovial fluid of human body.It has a high content in vitreous body and joint slide.It has unique properties such as high viscoelasticity,plasticity,permeability,non-toxicity,non-immunogenicity and good biocompatibilityObjective:1.To study the influence of HA on the foam stability of BLM2.To evaluate the clinical safety and efficacy of HA-BLM foam.Methods:1.Experimental study:Group A:6 IU BLM+2mL human serum albumin(HSA)+0 mL 1%HA+6mL air;Group B:6 IU BLM+1.95 mL HSA+0.05 mL 1%HA+6mL air;Group C:61U BLM+1.9 mL HSA+0.1 mL 1%HA+6 mL air;And Group D:6 IU BLM+1.85 mL HSA+0.15 mL 1%HA+6 mL air.Then,HA-BLM foam was prepared by Tessari’s method.The foam half-life time(FHT)was used to evaluate foam stability.2.Clinical study:Twenty-eight patients with head and neck VMs were enrolled between June 2018 and August 2019 treated by HA-BLM foam(6 IU BLM+1.95 mL HSA+ 0.05 mL 1%HA+6mL air)to evaluate the safety and efficacy.Experimental values were examined and analyzed,using SPSS 19.0 software package,by K-W test and t-test.Results:1.The FHT of BLM foam in groups A,B,C and D was 8.46,8.95,10.45 and 14.51 minutes,respectively2.All patients achieved significant efficacy,and no obvious side effects were observed.Conclusion:Addition a small amount of HA could improve the stability of BLM foam,and the treatment is safe and effectiveBackground:Foam sclerotherapy is becoming increasingly popular in the treatment of venous malformations(VMs).And owing to the simplicity of the procedure and the equipment required,foam sclerotherapy is now reportedly performed in consulting rooms,clinics,and operating rooms.Hospital-acquired infections(HAIs)include the infections that occur during hospitalisation or those inapparent during hospitalisation which become revealed post-discharge.These infections not only affect patients safety,but can also be a major hindrance to the hospital and society.The factors influencing HAIs not only include the various activities of the medical staff and the use of instruments but also include the environment,such as the air in the hospital.Human serum albumin(HSA),as the main component of bleomycin foam,potentially provides nutrition for bacterial growth.Objective:To study whether the risk of HAIs is increased with the use of air from outpatient treatment rooms to prepare bleomycin foam by comparing the bacterial counts in foam prepared with air from an outpatient treatment room and foam prepared with air from an operating theatre.Methods:1.Experimental study:Settling plates were adopted to collect bacteria from outpatient room air,operating theatre air,HSA,bleomycin solution,and bleomycin foam prepared with both outpatient room and operating theatre air.The plates were placed in an incubator at 37℃ for 48 hours,and the number of bacterial colonies was recorded using colony-forming units(CFU).The results were examined and analyzed using SPSS 19.0 software package by t-test.2.Clinical observation:A retrospective study,collecting information about patients with head and neck VMs who were treated using bleomycin foam in the outpatient treatment room or operating theatre at our hospital from June 2018 to October 2019 and making follow-up phone calls,was performed to evaluate the outpatient safety of bleomycin foam.Results:1.The number of CFUs in agar plates exposed to the air of the outpatient treatment room was significantly higher than that in the plates exposed to the air of the operating theatre.The number of CFUs was higher in the blood agar plates to which HSA was added than in the plates to which HSA was not added.After adding bleomycin to the blood agar plates,the number of colonies decreased significantly The number of CFUs in the bleomycin foam produced using both operating theatre and outpatient treatment room air was very low,with no significant difference between them.2.During our clinical observation,no infection cases were reported.Conclusion:1.Using the air from outpatient treatment rooms for bleomycin foam preparation does not increase the risk of HAIs;2.patients currently in clinical observation are safe.Background:Sclerotherapy is an effective method for the treatment of venous insufficiency.The Tessari’s method,mixing air with the sclerosant through a 3-way tap and two syringes,is the most widely used method to prepare foam in foam sclerotherapy.Objective:We aim to modify the traditional 3-way tap to produce more uniform and stable foam with smaller bubbles.Methods:1.Modified the 3-way tap:insert a porous film within its channel.2.Experiment design:The foam was prepared using 2 mL polidocanol(POL),with 8 mL of air and 0.05 mL of hyaluronic acid(HA).The structure of the foam was compared for 7 different types of foam production:group 1,20 quick passes through a traditional 3-way tap;and groups 2 through 7,using the modified 3-way tap,with 10,12,14,16,18,and 20 quick passes,respectively.The uniformity of the foam was observed under optical microscopy,and the size of bubbles quantified using the nano measurement software.The stability of the foam was evaluated using the foam half-life time(FHT)Results:The FHT increased with the number of passes in the modified 3-way tap,with values for groups 2 through 7,respectively,as follows:257.4 s,285.6 s,304.4 s,318.6 s,330.2 s,and 331.3 s.At 20 passes,the FHT was greater for the modified(331.3 s)than traditional(306.4 s)3-way tap.The modified tap also produced a more uniform distribution of smaller bubbles(groups 7)compared to traditional(group 1).Conclusion:Modified 3-way tap enhanced the stability of the sclerosant foam,with a more uniform distribution of smaller bubbles.