Vacuum Bell Research Articles

Failed preoperative vacuum bell therapy does not affect outcomes following minimally invasive repair of pectus excavatum

PurposeIt is unknown if failed preoperative vacuum bell (VB) treatment in patients undergoing minimally invasive repair of pectus excavatum (MIRPE), delays repair and/or affects postoperative outcomes.MethodsA retrospective data analysis including all consecutive patients treated at one single institution undergoing MIRPE was performed between 2000 and 2016. Patients were stratified into preoperative VB therapy versus no previous VB therapy.ResultsIn total, 127 patients were included. Twenty-seven (21.3%) patients had preoperative VB treatment for 17 months (median, IQR 8–34). All 27 patients stopped VB treatment due to the lack of treatment effect. Eight (47.1%) of 17 assessed VB patients showed signs of skin irritation or hematoma. VB treatment had no effect on length of hospital stay (p = 0.385), postoperative complications (p = 1.0), bar dislocations (p = 1.0), and duration of bar treatment (p = 0.174). Time spent in intensive care unit was shorter in patients with VB therapy (p = 0.007). Long-term perception of treatment including rating of primary operation (p = 0.113), pain during primary operation (p = 0.838), own perspective of look of chest (p = 0.545), satisfaction with the procedure (p = 0.409), and intention of doing surgery again (p = 1.0) were not different between groups.ConclusionsFailed preoperative VB therapy had no or minimal effect on short-term outcomes and long-term perceptions following MIRPE.

Vacuum Bell: Is It a Useful Innovative Device for Pectus Excavatum Correction?

Pectus Excavatum (PE) or "funnel chest," the most common deformity of the anterior chest wall characterized by sternal depression, can be repaired via either operative or non-invasive techniques. Vacuum Bell (VB) device is the most widespread of the latter one which can be applied either intraoperatively or as monotherapy. The present narrative review examines the efficacy of that innovative method. A thorough search of the literature resulted in 13 English-written articles concerning VB therapy from its first description to February 2019. The studies included patients with mild to moderate PE, mainly evaluated via Haller-Index and/or sternum depth prior to and following treatment. Concerning depth-improvement, 37-90% showed amelioration while 10-40% of them an excellent correction to normal. In 42%, Haller-Index also improved with a median decrease of 0.3 after VB application. A correlation was attempted to be found between the efficacy of VB and factors such as the frequency and duration of VB application, patient age, gender, PE severity and type, and differential pressure of the suction cup. Complications may be frequent yet mild and temporary. Intraoperatively, VB widows Minimally Invasive Repair of Pectus Excavatum (MIRPE) operation a safer procedure with greater results. VB as conservative treatment is an effective and well-tolerated alternative therapeutic option for selected patients with PE who meet specific criteria. It also constitutes a device of significant efficacy, appropriate for intraoperative use during MIRPE procedure.

Implementation and acceptance rates of a specially designed vacuometer for the vacuum bell treatment of pectus excavatum.

Background / PurposeTo report the implementation of a specially designed vacuometer for the ambulatory measurement of the exact negative pressure self-applied by the patient when using the vacuum bell for the treatment of pectus excavatum and to analyze patient satisfaction with the device, by conducting a survey. MethodsBetween October 2018 and June 2020, all patients with pectus excavatum who received a vacuum bell at our Pectus Clinic were provided with a specially designed pectus vacuometer for their personal use. We described the vacuometer, the fundamentals of its development, and the utilization protocol. A survey was conducted evaluating comfort, clarity of instructions, usefulness, simplicity of connection, and likeability. The level of satisfaction was assessed using a Likert scale ranging from 1 (very negative experience) to 5 (very positive experience). The occurrence of skin lesions provoked by the application of the vacuum bell was registered. ResultsFrom 72 submitted surveys, 54 patients answered. Patient demographics comprised 44 (81.5%) males and a mean age of 12.6 ± 6.0 years. The mean initial external pectus depth was 2.0 ± 0.7 cm and the mean duration of treatment was 13.2 ± 8.6 months. No skin lesions were detected while using the vacuum bell and the vacuometer. The mean general satisfaction score was 4.4 ± 0.7 and 83.3% of the respondents did not have any inconvenience with the vacuometer. A patient who considered himself cured was the only dropout during the study. ConclusionsIn this study, we described the feasibility and fundamentals of the application of a specifically designed vacuometer for ambulatory use as an adjunct to the treatment of pectus excavatum with a vacuum bell, and demonstrated a high satisfaction level with the device. In addition, the vacuometer might help avoid skin lesions secondary to the vacuum bell and foster adhesion to treatment. Type of studyTreatment study. Level of evidenceIV

Challenging beliefs:A review of the paradigm shift in the treatment of pectus excavatum from radical resection to minimally invasive bracing and non-surgical vacuum bell suction.

In 1997, Nuss introduced a minimally invasive non-destructive procedure for pectus excavatum, which revolutionised the treatment of the condition. This review will give a brief history on the management of this condition, followed by a review of 1 034 cases that have been repaired from 2008 to 2018.

Cardiovascular MRI assessment of pectus excavatum in pediatric patients and postoperative simulation using vacuum bell

BackgroundThe sternal lift by Vacuum Bell (VB) is effective, as largely demonstrated by its intraoperative use during surgical procedure to elevate the sternum during the Nuss procedure routinely. Indeed, the thoracic remodelling during VB application is comparable to post-surgical scenario, and suitable to compare cardiovascular parameters of the two different thoracic configurations immediately. ObjectiveWe would quantify and correlate preoperative parameters which determine the severity of the pectus excavatum (PE), and the cardiovascular effects at the baseline. Than we would assess the cardiovascular changes during VB positioning, mimicking the immediate, temporary effect of Pectus-correction. Materials and MethodsWe included 26 consecutive patients (mean age is 13,3 +/- 2,2 years) symptomatic and non, with a previous clinical diagnosis of PE. CMR was performed before and during application of VB, using the same imaging protocol. In both conditions, we measured thoracic indexes, and cardiac function as well as flow through main vessels. ResultsMean expiratory Haller Index (HI) was 5,4 (+/-1,4 SD; normal <3). During VB application, all patients showed improvement in the main morphologic parameters of the thorax (mean expiratory HI = 4,7 (+/-1,6 SD, delta -13%, P = 0,01). During VB application, a minimal but not significant increase of Right Ventricle End Diastolic Volume (RVEDVi) (delta +4,6%, P = 0,12), and Right Ventricle Ejection Fraction (RVEF) (delta +1,2%, P = 0,2) was observed. ConclusionIn adolescents affected by PE, cardiacMRI (CMR) demonstrates normal values of biventricular volume and systolic function. During VB application, beside significative improvements in chest wall anatomy, CMR shows a minimal positive variation in right ventricle volume and function. A minority of patients showed some degree of diastolic dysfunction at baseline, unchanged after VB application, with possible correlation between valve inflow and sternal impingement.

The vacuum treatment for the pectus excavatum thickened subcutaneous fat of the chest wall and is effective in preteenagers.

We report effects of treatment for pectus excavatum (PE) with a Vacuum Bell (VB). Fifteen patients (13 males and 2 females) undergoing VB therapy over 6years, aged 6-17years (mean: 11.1years), were divided into two Groups: Group 1 (G1), preteenagers (< 13years); Group 2 (G2), teenagers (≧ 13years). We retrospectively recorded changes in depth of depression and the Haller index. The depth of depression reduced in 93.3% of 15 patients (mean; 8.7mm). Minimal change occurred in the Haller index but the subcutaneous fat thickened significantly (11/15 patients). The improvement rate on elevation of the chest wall was better in G1 than G2 (G1: 54.0% vs G2: 51.3%). The maximum depth of depression improved in PE patients as a result of thickening of subcutaneous fat. VB is most effective in preteenagers with PE.

Facilitating robotic thymectomy in patients with pectus excavatum deformity.

Robotic procedures in the anterior mediastinum can be challenging in the existence of pectus excavatum deformity due to the limited intrathoracic working space caused by sternal depression. We propose that the temporary application of a vacuum bell device during the procedure can correct the deformity and thus, facilitate robotic approach similarly to the standard procedure.

Are non-radiation-based imaging modalities effective for objectively assessing and monitoring patients with pectus deformities?

A best evidence topic in thoracic surgery was written according to a structured protocol. The question addressed was 'What is the role of non-radiation-based imaging modalities in the management of pectus deformities?'. Altogether 29 papers were found using the reported search, of which 8 represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. We conclude that non-radiation-based imaging modalities provide a safe and easily implemented alternative to traditional computed tomography scan assessment for pectus deformities. This is particularly true for deformities on the more severe end of the spectrum and as an aid in providing an on-going assessment tool particularly in treatment modalities requiring a high degree of compliance (external bracing or vacuum bell therapy).

Physiotherapy in addition to vacuum bell therapy in patients with pectus excavatum.

Vacuum bell and exercise therapy are non-invasive treatments for pectus excavatum (PE). The purpose of this study was to determine the effects of the physiotherapy programme applied in addition to vacuum bell treatment in patients with PE. The study included 26 male patients with PE aged 11-18 years. Patients were randomly divided into 2 groups: group 1 received only vacuum bell treatment; group 2 had vacuum bell therapy and physiotherapy. Patient demographic and disease-related characteristics, type of sternal depression, perception of their deformity, postural evaluations, treatment satisfaction and quality of life were evaluated before and 12 weeks after treatment. From external chest circumference measurements related to PE, sternal depression and anthropometric index values showed improvement in both groups (P < 0.05), but better results were observed in group 2 than in group 1 (P < 0.05). Modified percent depth and scores from the T3 region (distance between the most prominent point of the sternum and the spinous process of the vertebra at the same level) showed improvement only in group 2 (P < 0.01), whereas severity of PE, the patient's perception of his deformity and parental physiological quality-of-life scores improved in both groups (P < 0.05). Posture, satisfaction with treatment and the patients' physiological quality-of-life scores were significantly better in group 2 (P < 0.05). Due to the additional improvements and greater satisfaction in the group receiving physiotherapy, we think that a proper rehabilitation programme should be applied simultaneously with the vacuum bell treatment in patients with PE. NCT04167865.

A novel three-dimensional printed vacuum bell for pectus excavatum treatment: a preliminary study

ObjectiveConservative treatment with a vacuum bell (VB) for pectus excavatum (PE) has now been gradually popularized as an alternative to surgery. We describe our initial experience with a novel three dimensional (3D) printed VB device.MethodsProspectively collected data of all patients who started using a 3D printed VB in 2018 at our institution were analyzed. Linear and logistic regressions were used to identify factors associated with effectiveness of device usage.ResultsIn total, forty-two patients with a median age of 3.6 years were treated with the device. The median follow-up duration was 11.1 months and the mean initial Depth Ratio (DR) was 0.129. There were no permanent sequelae from side effects. Thirty patients with at least one follow-up body scan data showed varying improvement (z = − 4.569, p = 0.0000). Linear regression suggested that longer usage improved outcomes (R2 = 0.235, p = 0.014). By logistic regression there was a trend of younger ages and less initial DR for better improvement though neither was statistically significant (p = 0.086, 0.078, respectively).ConclusionOur initial experience has shown the 3D printed VB may be as effective as other conventional VBs and could be used as an alternative to surgical treatment for selected patients with PE. More experience and studies with this type of VB are needed to demonstrate its superiority with regard to the 3D printing design and optimal timing and indication for use.

Noninvasive treatment of pectus excavatum with a vacuum bell combined with a three-dimensional scanner

Our aim was to evaluate the effect of a vacuum bell (VB) combined with a three-dimensional (3D) scanner for the noninvasive treatment of pectus excavatum (PE). A VB was used to create a vacuum at the anterior chest wall with a patient-activated hand pump, and it should be applied regularly for more than 2h each day at home. Eighty-two patients required to be followed up every three months were included in this retrospective study and distributed into four stages (stage 1: treated for 3months, stage 2: treated for 6months, stage 3: treated for 9months, and stage 4: treated for 12months). In addition, the deformity in the chest wall was scanned by a 3D scanner at the clinic, and the 3D depth (3D-DE) and 3D Haller index (3D-HI) of PE were calculated through Geomagic studio 2013 software. Eighty-two patients (12/2017-12/2019) met the criteria at the clinic, and 24 patients (29.3%) achieved excellent correction (3D-DE ≤ 3mm). When comparing the improvement in 3D-DE and 3D-HI of PE to the patient's treatment time, a statistically significant difference was observed between stages 2 and 1 (3D-DE p<0.01, 3D-HI p<0.01), stages 3 and 2 (3D-DE p<0.01, 3D-HI p<0.01) and stages 4 and 3 (3D-DE p<0.01, 3D-HI p<0.01). There was a statistically significant difference in sternum elevation between patients aged <10years and those aged ≥ 10years (3D-DE p = 0.006, 3D-HI p = 0.045) and patients with symmetrical and asymmetric PE (3D-DE p = 0.042, 3D-HI p = 0.032). However, there was no statistically significant difference in sternal elevation between males and females (3D-DE p = 0.27, 3D-HI p = 0.495). The main side effects were moderate subcutaneous hematoma, petechial bleeding, thoracalgia and chest tightness. With controllable side effects, noninvasive treatment for PE with a VB combined with a 3D scanner is safe, objective and radiation free, and the initial results to date are encouraging. Patients aged <10years, with symmetrical PE and treated for over 12months may achieve a better outcome.

Nitrous Oxide Decomposition Using Inductively Heated Heat Exchangers

Three different heat exchangers (copper metal foam, copper disks, and stainless-steel disks) with lower effective surface areas than nominal catalysts used in thrusters were tested for nitrous oxide decomposition. These heat exchangers were preheated to thermal decomposition temperatures using an inductive heating system and placed in a vacuum bell jar to mitigate heat loss to the environment. Testing with copper metal foam resulted in complete degradation of the heat exchanger due to oxidation from nitrous oxide decomposition. A set of copper disks, uniquely designed to maximize tortuosity of the flow, was implemented in an attempt to address the oxidation issues. While the preliminary test did confirm steady-state decomposition of nitrous oxide within the heat exchanger, further tests resulted in temperatures exceeding the melting point of copper within the disks. The last heat exchanger was a set of stainless-steel disks of the same design. Repeated tests all successfully achieved steady-state decomposition of nitrous oxide within a 2 min interval.

Recent Modifications of the Nuss Procedure: The Pursuit of Safety During the Minimally Invasive Repair of Pectus Excavatum.

To review standardized Nuss correction of pectus excavatum and vacuum bell treatment over the last 10 years. In 2010, we reported 21 years of the Nuss procedure in 1215 patients. Over the last 10 years, 2008-2018, we evaluated 1885 pectus excavatum patients. Surgery was indicated for well-defined objective criteria. A consistent operation was performed by 8 surgeons in 1034 patients, median 15 years, (range 6-46); 996 were primary, and 38 redo operations. Surgical patients' mean computed tomography index was 5.46. Mitral valve prolapse was present in 5.4%, Marfan syndrome in 1.1% and scoliosis in 29%. Vacuum bell treatment was introduced for 218 patients who did not meet surgical criteria or were averse to surgery. At primary operation, 1 bar was placed in 49.8%; 2 bars, 49.4%; and 3 bars, 0.7%. There were no deaths. Cardiac perforation occurred in 1 patient who had undergone previous cardiac surgery. Paraplegia after epidural catheter occurred once. Reoperation for bar displacement occurred in 1.8%, hemothorax in 0.3%, and wound infection in 2.9%; 1.4% required surgical drainage. Allergy to stainless steel was identified in 13.7%. A good anatomic outcome was always achieved at bar removal. Recurrence requiring reoperation occurred in 3 primary surgical patients. Two patients developed carinate overcorrection requiring reoperation. Vacuum bell treatment produced better results in younger and less severe cases. A standardized Nuss procedure was performed by multiple surgeons in 1034 patients with good overall safety and results in primary repairs. Vacuum bell treatment is useful.

Cardiovascular magnetic resonance assessment of biventricular changes during vacuum bell correction of pectus excavatum.

Evidence of cardiac dysfunction in patients with pectus excavatum (PE) remains controversial. A growing number of studies report increased exercise tolerance following surgery. Nevertheless, many consider the correction of PE a cosmetic intervention, with post-operative changes ascribed to the concurrent growth of the young patient population. No studies have investigated non-invasively the immediate cardiac changes following relief of the deformity. The aim of this study was to assess cardiac function before and during temporary sternal elevation using the non-invasive vacuum bell (VB) device on young adults with PE. Adult patients scheduled for surgical correction of PE underwent cardiac magnetic resonance imaging (CMRI) before and during the application of the VB. Steady-state free precession sequences were used for the evaluation of biventricular volume and function. Phase contrast sequences measured the aortic and pulmonary flow to calculate stroke index (SI). Scans were analyzed post hoc by the same investigator. A control group of healthy individuals was assessed in the same way. In total, 20 patients with PE (mean age 23±10 years) and 10 healthy individuals (mean age 25±6 years) underwent CMR before and during VB application. Before intervention, baseline cardiac volumes and function were similar between the groups, with patient-values in the low-to-normal range. Following VB application, PE patients revealed a 10% increase in biventricular SI. Furthermore, left ventricular end-diastolic volume index (LV EDVI) improved by 8% and right ventricular ejection fraction (RV EF) increased by 7%. These findings were not mirrored in the healthy individuals. No correlations were found between improved cardiac parameters and the baseline Haller index (HI) of PE patients. Non-invasive, momentary correction of PE is associated with an immediate improvement in SI, RV EF and LV EDVI, not observed in controls. The findings suggest that sternal depression in PE patients affects cardiac function.

The consistency of an optical body surface scanning method compared with computed tomography: a validation study

ObjectiveThe ideal noninvasive method for evaluation of pectus excavatum remains to be defined. We sought to verify the accuracy of an optical body surface scanning method compared with conventional CT scan. Materials and methodsA PrimeSense 3D sensor was used to obtain data from patients undergoing surgical or noninvasive treatment for pectus excavatum. The Haller index, external Haller index, and depth ratio were then calculated from both body scan and computed tomography scan data for the same patients. Statistical analyses were carried out to find if there is consistency between data from body scanning and computed tomography. ResultsData acquisition was complete. In total, 40 patients (median age: 5.03 years, 11 female) with pectus excavatum undergoing nonoperative (n = 13) or surgical Nuss treatment (n = 27) were included. The Haller index was lower in vacuum bell patients, which also had a higher female proportion. Pearson correlation coefficient between external Haller indices from body scanning and from computed tomography and between the depth ratios from body scanning and from computed tomography were 0.63 and 0.84, respectively. By intraclass correlation coefficient method, the correlation coefficient was 0.56 between external Haller indices from body scanning and from computed tomography and 0.80 between depth ratios from body scanning and from computed tomography. ConclusionThe optical body surface scanning is a reliable approach to the measurement of PE severity and could be routinely used in the monitoring of PE development of treatment, especially in the pediatric population. Study typeDiagnostic test. Level of evidenceLevel II.

An argumentation-based demonstration experiment in teaching the light–matter interaction

This paper presents an argumentation-based demonstration experiment to teach the light–matter interaction using an observable laser beam and vacuum pump. In the experiment, the concept of darkness was addressed using a virtual space environment created by gradually decreasing the pressure inside a quartz glass bell jar with a vacuum pump. This experimental activity, offering an evidence-based inquiry, deepened the conceptual understanding of the students in relation to the light–matter interaction and other events that occurred following the decrease in the intensity of light entering the eye, caused by the reduced pressure in the vacuum bell jar.

Sternal elevation techniques during the minimally invasive repair of pectus excavatum.

The aim of the review was to evaluate the routine use of sternal elevation techniques (SETs) during minimally invasive repair of pectus excavatum (MIRPE, the Nuss procedure). We performed a review of the literature between January 1998 and September 2018 with focus on different methods of SET during MIRPE. Reported effects and side effects were evaluated and compared with our own experience concerning the routine use of the vacuum bell for sternal elevation during MIRPE during the last 13 years. SET is more often used in adult patients than in adolescents. SET improves visualization and safety of MIRPE. Advancement of the pectus introducer, retrosternal dissection and placement of the pectus bar are easier. The risk of cardial and/or pericardial lesion is reduced significantly. Different types of retractors, a crane combined with a wire and/or customized hooks are reported to be used as SET. Furthermore, routine use of a subxiphoid incision is reported. However, more technical equipment, and in some SETs additional incisions are necessary. In contrast, no additional skin incision is necessary for the vacuum bell. The routine intraoperative use of the vacuum bell was safe and effective in 131 patients. It facilitates the retrosternal dissection and the insertion of the pectus bar like other SETs. Besides a temporary mild hematoma, no relevant side effect was observed. In conclusion, an increasing number of authors report on the routine use of SET during MIRPE to improve safety of the procedure. We recommend the routine intraoperative use of the vacuum bell during MIRPE.

Is vacuum bell therapy effective in the correction of pectus excavatum?

A best evidence topic in thoracic surgery was written in accordance to a structured protocol. The question addressed was: 'In patients with a pectus excavatum deformity, is vacuum bell therapy (VBT) an effective treatment?' Altogether, 19 papers were found using the reported search of which 7 represented the best evidence to answer the clinical questions. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. Numerous groups have demonstrated the utility of VBT in pectus excavatum; the largest series has followed up patients over 13 years with sternal elevation of >1 cm being demonstrated in 105 patients. Initial age <11, initial chest wall depth <1.5 cm and chest wall flexibility have all been associated with better outcomes. The effects of VBT have been confirmed on computed tomography scanning and intraoperatively to lift the sternum to facilitate retrosternal soft tissue dissection during the Nuss procedure. There was significant heterogeneity in the studies reviewed, in terms of patient age, selection criteria, the VBT protocol, length of follow-up time following completion of VBT and the metrics used to assess success of therapy. VBT is a safe therapy for treating pectus excavatum in a non-surgical conservative manner with few complications reported. However, the success of VBT is largely dependent on patient compliance and motivation. Permanence of correction after completion of VBT needs to be properly assessed through rigorous follow-up, and currently the success of correction, i.e. permanence, remains in the hands of the patient.

Vacuum bell application in patients with pectus excavatum

Vacuum bell application in patients with pectus excavatum

Use of an Optical Scanning Device to Monitor the Progress of Noninvasive Treatments for Chest Wall Deformity: A Pilot Study.

BackgroundThe nonsurgical treatment of chest wall deformity by a vacuum bell or external brace is gradual, with correction taking place over months. Monitoring the progress of nonsurgical treatment of chest wall deformity has relied on the ancient methods of measuring the depth of the excavatum and the protrusion of the carinatum. Patients, who are often adolescent, may become discouraged and abandon treatment.MethodsOptical scanning was utilized before and after the intervention to assess the effectiveness of treatment. The device measured the change in chest shape at each visit. In this pilot study, patients were included if they were willing to undergo scanning before and after treatment. Both surgical and nonsurgical treatment results were assessed.ResultsScanning was successful in 7 patients. Optical scanning allowed a visually clear, precise assessment of treatment, whether by operation, vacuum bell (for pectus excavatum), or external compression brace (for pectus carinatum). Millimeter-scale differences were identified and presented graphically to patients and families.ConclusionOptical scanning with the digital subtraction of images obtained months apart allows a comparison of chest shape before and after treatment. For nonsurgical, gradual methods, this allows the patient to more easily appreciate progress. We speculate that this will increase adherence to these methods in adolescent patients.