A Case of Postoperative Noncardiogenic Edema: Negative Pressure Pulmonary Edema.

A case of complete recovery of negative pressure pulmonary edema after a Cottle surgery in a 24-year-old male. Teaching point: Negative pressure pulmonary edema is an important cause of postoperative noncardiogenic edema, with the spontaneous disappearance of all complaints within a relatively short period.

A novel intervention for wound bed preparation in severe extremity trauma: Highly concentrated carbon dioxide bathing.

Introduction: In severe extremity trauma involving large tissue defects, early closure (e.g., free-flap surgery) of the defects is an essential step for good functional reconstruction; however, in some cases, early closure may be difficult. Highly concentrated carbon dioxide bathing, used to improve blood flow in ischemic limbs and skin ulcers, can also be applied in wound bed preparation for severe limb trauma. Patients and Methods: The three cases in this study required an average of 13 weeks of highly concentrated carbonated bathing, which led to significantly better wound bed preparation, even in the exposed bone and tendon regions. Results: We successfully achieved good functional limb reconstruction in patients with deep burns and severe open fractures by reducing wound infection and facilitating good wound bed preparation. Conclusions: Highly concentrated carbon dioxide bathing was sufficient to prevent frequent wound infections, even in severe extremity trauma involving large soft-tissue defects such as deep crush burns and Gustilo Anderson classification ≥3b open fractures of the extremities. To our knowledge, such interventions have not been reported in the past and are valuable as new procedures for wound bed preparation in severe extremity trauma from both cost and wound infection control perspectives.

Perineal laceration treated with negative pressure wound therapy following colostomy.

A male in his early 30s was transported to the emergency room after being hit by a vehicle while inebriated and lying in the street. His general condition was stable; however, he had a perineal laceration that extended to the coccyx. Due to the proximity of the wound margin to the anus, we were concerned regarding the potential contamination and opted not to suture it. Therefore, we refrained from suturing the wound and kept the wound open after irrigation and debridement. Additionally, we performed a transverse colostomy. On day 4, we initiated negative pressure wound therapy for 40 days, during which sufficient wound granulation occurred. The patient was discharged, and the colostomy was closed approximately 4 months after the injury. Our case illustrates the effectiveness of negative pressure wound therapy in managing perineal lacerations.

Unmasking Negative Pressure Pulmonary Edema Following Hanging: A Case Series.

Pulmonary edema is a rare mechanism of death that develops after partial hanging, a potential complication that physicians should consider early in the management of these patients. This case series discusses the presentation, evaluation, and treatment course of three patients who had attempted suicide by hanging and were admitted to the hospital. These patients were admitted to the intensive care unit after being stabilized and supportive treatment was provided. In all the cases, a radiological scan of the chest revealed diffuse infiltrates consistent with pulmonary edema on both sides, features of which were also noted during a diagnostic bronchoscopy. After providing the best intensive care in the hospital, two patients clinically improved, and one patient succumbed to cardiac arrest. As most patients will be brought dead to the hospital following hanging, negative pressure pulmonary edema remains underdiagnosed. Thus, this case series enumerates the possible etiologies of negative pressure pulmonary edema and its contribution to death following suicidal hanging.

Negative Pressure Wound Therapy in Pharyngocutaneous Fistula.

Pharyngocutaneous fistula (PCF) is an abnormal connection between the pharynx and skin that can occur after laryngectomy surgery. It can have a significant negative impact on patient recovery, delaying wound healing, requiring prolonged nil-per-oral (NPO) status, and reducing quality of life. Traditionally, the management of PCF has relied on conservative measures or surgical intervention. However, negative pressure wound therapy (NPWT) offers a promising alternative approach. This case study involves three patients who underwent laryngectomy and developed postoperative PCF. All patients received NPWT with a modified suction catheter and low negative pressure (20-40 mmHg). With NPWT, all patients achieved complete wound closure, with healing times ranging from two weeks to six weeks. This suggests that NPWT may significantly accelerate PCF healing compared to traditional methods. However, maintaining an airtight dressing on the neck region can be challenging. This study highlights the potential of NPWT for faster PCF closure after laryngectomy. Further research is needed to optimize NPWT application techniques, explore the impact on long-term outcomes, and establish guidelines for broader clinical use.

Transcutaneous vagal nerve stimulation during lower body negative pressure.

BACKGROUND: Para-sympathetic vagal activation has profound influence on heart rate and other cardiovascular parameters. We tested the hypothesis that transcutaneous Vagal Nerve Stimulation (tVNS) through the auricular branch of the vagus nerve would attenuate the normal sympathetic response to central blood volume reduction by lower body negative pressure (LBNP). METHOD: 10 healthy volunteers (6 female; age 21 ± 2 years; weight 62 ± 13 kg; height 167 ± 12 cm) were included in this cross-over design trial. After 15 min rest in supine position, subjects underwent three 15-min periods of 30 mmHg LBNP intervention with and without cyclic tVNS stimulation. Continuous cardiovascular parameters (Nexfin) were recorded. RESULTS: Overall tVNS did not convincingly attenuate sympathetic response to central hypovolemia. Deactivation of the tVNS during LBNP resulted in increased MAP at 2.3 ± 0.5 mmHg (P < 0.001). Comparing the cyclic actual active stimulation periods to periods with pause during tVNS intervention showed a decrease in HR by 72.9 ± 11.2 to 70.2 ± 11.6 bpm (mean ± SD; P < 0.05), and concomitant increases in SV (86.0 ± 12.1 to 87.2 ± 12.6 mL; P < 0.05), MAP (82.9 ± 6.3 to 84.0 ± 6.2 mmHg; P < 0.05) and TPR (1116.0 ± 111.1 to 1153 ± 104.8 dyn*s/cm5; P < 0.05). CONCLUSION: tVNS in 30 s cycles during LBNP can selectively attenuate HR, prompting a compensatory augmented sympathetic response. It would appear the method used in this study at least, has an isolated cardiac inhibitory effect probably mediated by augmented vagal activity on the sinoatrial or atrio-ventricular node, possibly in combination with reduced activity in the sympathetic cardiac nerve.

Enhancing Healing Strategies: Negative-Pressure Wound Therapy and Delayed Primary Closure in Abdominal Wounds Post-emergency Laparotomy for Intestinal Perforation.

Background Intestinal perforation is a life-threatening condition requiring immediate surgical intervention. Surgical-site infections (SSIs) and wound dehiscence are common complications associated with emergency laparotomy for intestinal perforation. Finding optimal wound management and postoperative strategies can significantly impact patient outcomes and reduce the risk of complications. Negative-pressure wound therapy (NPWT) is a relatively recent tool employed in the care of wounds to control SSIs and foster healing. Methodology A prospective, observational, cohort study was conducted among 150 patients who underwent emergency exploratory laparotomy due to intestinal perforation at the general surgery department of a tertiary care hospital in New Delhi between July 2022 and December 2023. Preoperatively, all patients underwent initial resuscitation. Intraoperatively, the extent of peritonitis was determined and was categorized according to the Centers for Disease Control and Prevention (CDC) classification. Postoperatively, NPWT dressing was applied to the patient's midline laparotomy wound on postoperative day (POD) two. Negative pressure was set at 75-125 mmHg with suction. The number of NPWT dressing changes required was documented. The wound was closed with vertical mattress sutures under local anesthesia, delayed primary closure (DPC). The incidence of SSIs, the duration for DPC, the incidence of fascial dehiscence, the number of NPWT dressing changes, and the length of hospital stay were documented according to CDC groups. Results The mean age in CDC categories 2, 3, and 4 were 31.789, 28.733, and 42.676 years, respectively. The most common cause of perforation was enteric fever (n = 42, 28%), followed by tuberculosis (n = 36, 24%). Most patients had no known comorbidities (n = 80, 53.3%). Overall, 16% of patients (n = 24) were both alcoholics and smokers. The most frequent bacteria in all CDC categories was Escherichia coli. Fourteen patients developed burst abdomen in the postoperative period and were excluded from the study. The mean duration of DPC increased with higher CDC categories, with CDC category 4 displaying the most extended mean duration at 10.70 days. The number of NPWT dressing changes increases with higher CDC categories, with CDC category 4 exhibiting the highest mean at 2.00 changes. The mean hospital stay increased with higher CDC categories, with CDC category 4 showing the most extended mean stay at 17.324 days. Statistical analysis revealed no significant association between SSI occurrence and CDC categories. Conclusions NPWT followed by DPC is a promising approach to managing gastrointestinal perforations, reducing SSIs, and potentially improving patient outcomes. However, further research is needed to explore the specific benefits of NPWT in conjunction with DPC and its efficacy in various clinical scenarios.

Negative Pressure Level and Effects on Bacterial Growth Kinetics in an in vitro Wound Model.

Negative Pressure Wound Therapy (NPWT) has been widely adopted in wound healing strategies due to its multimodal mechanism of action. While NPWT's positive impression on wound healing is well-established, its effect on bacterial load reduction remains equivocal. This study investigates NPWT's efficacy in reducing bioburden using an in vitro porcine skin model, focusing on the impact of Staphylococcus aureus and Staphylococcus epidermidis. Custom-made negative pressure chambers were employed to apply varying negative pressures. Porcine skin was cut into 5 × 5 cm squares and three standardized wounds of 6 mm each were created using a biopsy punch. Then, wounds were infected with S. aureus and S. epidermidis bacterial suspensions diluted 1:10,000 to obtain a final concentration of 1.5 × 104 CFU/ml and were placed in negative pressure chambers. After incubation, bacterial counts were expressed as colony-forming units (CFU) per ml. For S. aureus at 120 hours, the median CFU, mean area per colony, and total growth area were notably lower at -80 mmHg when compared to -250 mmHg and -50 mmHg, suggesting an optimal negative pressure for the pressure-dependent inhibition of the bacterial proliferation. While analyzing S. epidermidis at 120 hours, the response to the negative pressure was similar but less clear, with the minor CFU at -100 mmHg. The influence of intermittent negative pressure on the S. epidermidis growth showed notably lower median CFU with the interval therapy every hour compared to the S. aureus control group. This study contributes valuable insights into NPWT's influence on the bacterial load, emphasizing the need for further research to reformulate its role in managing contaminated wounds.

Medicine's Glass Slipper: The PAVAEX Boot and 20th Century Negative Pressure Therapy.

Before the 20th century, peripheral artery disease (PAD) manifested as extreme pain, chronic wounds, and, eventually, gangrene requiring amputation. Despite this, it was rarely diagnosed. However, at the turn of the century, Western medicine shifted focus from infectious to chronic illnesses, and with this change, physicians' engagement with PAD transformed. Aiming to mitigate long-term injury, physicians now worked to identify and treat vessel disease to restore meaningful blood circulation. This article explores the development and deployment of a new device resulting from this refocus, the PAssive VAscular EXerciser (PAVAEX) Boot, and its role as a creative response to a previously intractable clinical problem. The PAVAEX Boot, designed in 1933 by vascular surgeons Louis G. Herrmann and Mont R. Reid, was one of the few interventions for PAD at the time. Based on the observation that continuous negative pressure results in vasoconstriction, while short bursts transiently increase blood flow, the PAVAEX Boot utilized intermittent negative pressure to enhance peripheral vascular perfusion. Well-marketed and praised throughout the 1930s, it vanished from public writing and academic literature just 20 years later. However, negative pressure wound therapy resurged in the late 20th century, and though its inventors failed to recognize the precedent of the PAVAEX Boot, many of these devices and therapies are rooted in identical theories. We examine why the PAVAEX Boot faded from use and argue that the device remains a crucial advancement in negative pressure therapy.

A Case Report of Pin Site Osteomyelitis after 17 Years of External Fixator Application to Distal Radius Fracture.

This case report presents an uncommon long-term complication of external fixator application to distal radius fracture. Despite an initial uneventful fracture healing, the patient presented with Brodie's abscess with Staphylococcus aureus osteomyelitis at the previous pin site 17 years later. A diagnosis of late-onset osteomyelitis, as a manifestation of quiescence chronic osteomyelitis, was made.

The ACS-NSQIP Analysis of Negative Pressure Wound Therapy Following Pancreatectomy for Pancreatic Diagnoses.

Introduction Surgical site infections (SSIs) continue to be a challenging issue among patients undergoing pancreatectomy. Anecdotally, the use of negative pressure wound therapy (NPWT) following pancreatectomy for cancer has been associated with decreased SSIs. The objective of this study was to compare the postoperative outcomes of NPWT and non-NPWT for incisional wound care following distal pancreatectomy or pancreatoduodenectomy for pancreatic diagnoses using a national surgical database. Methods The American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) was queried from 2005 to 2019 for patients undergoing distal pancreatectomy or pancreaticoduodenectomy for pancreatic diagnoses using primary Current Procedural Terminology (CPT) codes. The primary outcome was surgical site infection rates between NPWT and non-NPWT patient groups. Secondary outcomes include sepsis, septic shock, readmission, and reoperation. Outcomes of interest were compared using multivariate logistic regression. Results A total of 54,457 patients underwent pancreatectomy with 131 receiving NPWT. Multivariate analysis, while accounting for patient characteristics, including wound classification, showed no difference in postoperative superficial SSI, deep SSI, sepsis, septic shock, or readmission between the NPWT and non-NPWT groups. Organ space SSI was higher in the NPWT group (21% vs 12%, p=0.001). Reoperation related to procedure was also high in the NPWT group (14% vs 4.3%, p<0.001). Conclusion The use of NPWT in distal pancreatectomies and pancreatoduodenectomies is associated with increased organ space SSIs and reoperation rates, with no difference in superficial SSI, deep SSI, or readmission. This large sample study shows no significant benefit of using NPWT incisional wound care after pancreatectomy.

Negative Pressure Wound Therapy with Instillation and Dwell Time for Pharyngocutaneous Fistula.

Pharyngocutaneous fistula is a critical complication of head and neck cancer reconstruction and it is often difficult to manage. We herein report two cases of pharyngocutaneous fistulas that developed after oropharyngeal reconstruction and were successfully treated with negative pressure wound therapy with instillation and dwell time (NPWTi-d), an advanced form of traditional NPWT. NPWTi-d may be a useful nonsurgical treatment for pharyngocutaneous fistula. Laryngoscope, 2024.

An exploratory randomized clinical trial on negative pressure wound therapy for lower limb full-thickness skin grafts of dermatosurgical patients.

Full-thickness skin graft (FTSG) reconstructions of lower limbs are especially prone to wound complications. Negative pressure wound therapy (NPWT) enhances wound healing, but no broad evidence exists if it promotes graft take of lower leg FTSGs. In this investigator-initiated, prospective, randomised and controlled trial, 20 patients with ambulatory FTSG reconstruction for lower limb skin cancers were randomised for postoperative treatment with either NPWT, or conventional dressings. As outcomes, adherence of the skin graft 1 week postoperatively, any wound complications within 3 months, including ≥3 weeks delayed wound healing, and the number of additional postoperative visits were compared. In both groups, grafts adhered equally well (p = 0.47); 80% of NPWT-treated and 100% of control group grafts adhered >90%. There was no significant difference in the number of postoperative complications/delayed wound healing (p = 0.65); 70% of patients in the NPWT and 50% in the control group developed a wound complication. Both groups had an equal number of patients with at least three additional control visits (p = 1.0). The study was discontinued after 20 patients were recruited, as no benefit from NPWT was seen. To conclude, the study showed no benefit from NPWT for lower limb FTSGs.

Closed Incision Negative Pressure Therapy Versus Standard of Care Over Closed Abdominal Incisions in the Reduction of Surgical Site Complications: A Systematic Review and Meta-Analysis of Comparative Studies.

Background: Surgical site complications (SSCs) pose a significant risk to patients, potentially leading to severe consequences or even loss of life. While previous research has shown that closed incision negative pressure therapy (ciNPT) can reduce wound complications in various surgical fields, its effectiveness in abdominal incisions remains uncertain. To address this gap, a systematic review and meta-analysis were conducted to assess the impact of ciNPT on postsurgical outcomes and health care utilization in patients undergoing open abdominal surgeries. Methods: A systematic literature search using PubMed, EMBASE, and QUOSA was performed for publications written in English, comparing ciNPT with standard of care dressings for patients undergoing abdominal surgical procedures between January 2005 and August 2021. Characteristics of study participants, surgical procedures, dressings used, duration of treatment, postsurgical outcomes, and follow-up data were extracted. Meta-analyses were performed using random-effects models. Dichotomous outcomes were summarized using risk ratios and continuous outcomes were assessed using mean differences. Results: The literature search identified 22 studies for inclusion in the analysis. Significant reductions in relative risk (RR) of SSC (RR: 0.568, P = .003), surgical site infection (SSI) (RR: 0.512, P < .001), superficial SSI (RR: 0.373, P < .001), deep SSI (RR: 0.368, P =.033), and dehiscence (RR: 0.581, P = .042) were associated with ciNPT use. ciNPT use was also associated with a reduced risk of readmission and a 2.6-day reduction in hospital length of stay (P < .001). Conclusions: These findings indicate that use of ciNPT in patients undergoing open abdominal procedures can help reduce SSCs and associated hospital length of stay as well as readmissions.A previous version of this abstract was presented at the 2023 Conference of the European Wound Management Association (EWMA) in Milan, Italy and posted online at the site listed below. EWMA permits abstracts to be republished with the complete manuscript. https://journals.cambridgemedia.com.au/application/files/9116/8920/7316/JWM_Abstracts_LR.pdf.

In situ methane enrichment with vacuum application to produce biogas with higher methane content.

Sludge produced in sewage treatment plants is an important source of organic matter to be used in anaerobic digestion to produce energy-rich biogas. The biogas produced in anaerobic digesters has a critical impact on achieving carbon neutrality and improving energy self-sufficiency. After effective upgrading, biogas can be converted into biomethane with an increased CH4 content, resulting in a higher volumetric energy value. Upgrading biogas to biomethane thus not only improves its energy content but also broadens its potential uses. In this study, it was aimed at enrich CH4 by removing dissolved CO2 from the digestate using a vacuum, leveraging the solubility differences of gases in liquid. In this context, two digesters (R-T and R-C) were operated for 194 days, and the effect of vacuum on in-situ methane enrichment was investigated. The vacuum was only applied to the test reactor (R-T), and the CH4 percentage was increased from 63 to 87, 80, and 75% in the vacuum exposure time intervals of 30, 10, and 5 min, respectively. Extended durations were not tested, as the rate of enrichment decreased sharply after 30 min. The maximum energy requirement of a vacuum application was estimated at 0.124 kWh/m3 methane. Conversely, vacuum application did not cause any deterioration in biogas production, and the methane yields were similar in both reactors.

Is Staged Surgery Always Necessary for Schatzker Type IV-VI Tibial Plateau Fractures? A Comparison Study.

AIMS: This study aims to compare the outcomes of immediate (followed by closed-incision negative-pressure therapy use) versus delayed ORIF in patients with Schatzker type IV-VI TPFs. PATIENTS AND METHODS: A prospective study of patients undergoing ORIF between January 2018 and December 2019 was performed. The inclusion criteria were patients (>18 years) with a closed fracture sent to the emergency room (ER) within 24 h of injury. All the patients underwent preoperative image evaluation. Two senior orthopedic trauma surgeons evaluated the soft tissue condition in the ER by 5P's of the compartment syndrome, judging the timing of the operation of definitive ORIF. Group 1 (n = 16) received delayed ORIF. Group 2 (n = 16) received immediate ORIF and ciNPT use. Patient follow-up occurred after 2 and 6 weeks and 3, 6, and 12 months after surgery. The assessments included the time to definitive fixation, the length of hospital stay, the time to bone union, surgical site complications, and reoperation within 12 months. A universal goniometer was used to measure the postoperative 3 m, 6 m, and 12 m ROM. RESULTS: The patient demographics were similar between the groups (p > 0.05). Group 2 displayed significantly a shorter time to definitive fixation (5.94 ± 2.02 vs. 0.61 ± 0.28, p < 0.0001) and hospital stay (14.90 ± 8/78 vs. 10.30 ± 6.78, p = 0.0016). No significant difference was observed in the time to bone union, surgical site complication incidence, and reoperation rates (p > 0.05). Flexion and flexion-extension knee ROM were demonstrated to be significantly improved in Group 2, 3, 6, and 12 months postoperatively (p < 0.0001). CONCLUSIONS: In this study, early ORIF and ciNPT use resulted in a shorter hospital length of stay, a reduced time to early active motion of the knee, and improved knee ROM. These results suggest that early ORIF with ciNPT for Schatzker type IV-VI TPFs is safe and effective in some patients. However, further research to confirm these findings across larger and more diverse populations is needed.

The effectiveness of negative pressure therapy in burns: scoping review / A efetividade da terapia por pressãonegativa em queimaduras: revisão de escopo / La efectividad de la terapia de presiónnegativa en quemaduras: revisión del alcance

Objetivo: Mapear a produção científica a respeito do uso da terapia de pressão negativa no tratamento de queimaduras, em pacientes adultos e idosos hospitalizados. Método: Revisão de escopo seguindo o método da JBI com busca da produção científica na PubMed, Scientific Electronic Library Online, Biblioteca Virtual de Saúde e Banco de Teses da Coordenação de Aperfeiçoamento de Pessoal de Nível Superior nos meses de março a maio de 2021. Foram incluídos estudos com pacientes adultos e idosos com queimaduras, submetidos à terapia por pressão negativa no hospital. Não houve restrição de idioma, nem período de tempo. Resultados: Foram identificadas 106 publicações e, após o processo de seleção, cinco estudos compuseram a amostra final. Os resultados demonstraram que a aplicação da terapia por pressão negativa em queimaduras constituiu-se como uma ferramenta efetiva na cicatrização de queimaduras térmicas, químicas e elétricas, destacando-se a otimização do tempo de cicatrização, formação de um tecido de granulação saudável, diminuição do edema, redução da infecção, drenagem e monitorização do edema. Conclusão: O tratamento de queimaduras utilizando a pressão negativa tem se mostrado um método efetivo, visto os benefícios que promove no processo cicatricial. Sugere-se que a temática seja mais difundida, aprofundando-se o conhecimento sobre o uso desta tecnologia. (AU)

Objective: To map the scientific production regarding the use of negative pressure wound therapy in burn treatment of hospitalized adult and aged patients. Method: Scope review following the JBI method with a search for scientific production in PubMed, the Scientific Electronic Library Online, the Virtual Health Library, and the Thesis Database of the Coordination for the Improvement of Higher Education Personnel from March to May 2021. Studies with adult and aged burn patients undergoing negative pressure wound therapy in hospitals were included. There was no language or time frame restriction. Results: 106 publications were identified and 5 studies made up the final sample after the selection process. The results demonstrated that applying negative pressure wound therapy to burns was effective in healing thermal, chemical, and electrical burns, esoecially regarding healing time optimization, healthy granulation tissue formation, edema and infection reduction, and edema drainage and monitoring. Conclusion: Burn treatment using negative pressure has proven effective, given the benefits it promotes in the healing process. The theme should be more widely spread to deepen the knowledge about the use of this technology. (AU)

Objetivo: Mapear la producción científica sobre el uso de la terapia de presión negativa en el tratamiento de quemaduras en pacientes adultos y ancianos hospitalizados. Método: Revisión de alcance siguiendo el método JBI con búsqueda de producción científica en PubMed, Biblioteca Científica Electrónica en Línea, Biblioteca Virtual en Salud y Banco de Tesis de la Coordinación para el Perfeccionamiento del Personal de Educación Superior en los meses de marzo a mayo de 2021. Se incluyeron estudios con adultos y pacientes ancianos quemados sometidos a terapia de presión negativa en el hospital. No hubo restricción de idioma ni período de tiempo. Resultados: Se identificaron 106 publicaciones y luego del proceso de selección, 5 estudios conformaron la muestra final. Los resultados demostraron que la aplicación de la terapia de presión negativa en quemaduras constituyó una herramienta eficaz en la curación de quemaduras térmicas, químicas y eléctricas, destacándose la optimización del tiempo de curación, formación de tejido de granulación sano, reducción de edema, reducción de infección, drenaje y seguimiento del edema. Conclusión: El tratamiento de quemaduras mediante presión negativa ha demostrado ser un método efectivo, dados los beneficios que promueve en el proceso de cicatrización. Se sugiere que el tema sea más difundido, profundizando el conocimiento sobre el uso de esta tecnología. (AU)

Negative pressure wound therapy in burns: a prospective, randomized-controlled trial.

BACKGROUND: Negative-pressure-wound-therapy (NPWT) has become a widely used tool for the coverage and active treatment of complex wounds, including burns. This study aimed to evaluate the effectiveness of NPWT in acute burns of upper and lower extremities and to compare results to the standard-of-care (SOC) at our institution. METHODS: Patients that were admitted to our institution between May 2019 and November 2021 with burns on extremities between 0.5 % and 10 % of the total body surface area (%TBSA) were included and randomized to either NPWT or SOC (polyhexanide gel, fatty gauze, and cotton wool). Treatment was performed until complete wound healing. Patients that required skin grafts, received additional NPWT after grafting independent on the initial group allocation. RESULTS: Sixty-five patients suffering from burn injury between May 2019 and November 2021 were randomized into treatment with NPWT (n = 33) or SOC (n = 32); of these, 33 patients (NPWT) and 28 patients (SOC) had complete data sets and were included in the analysis. Both groups were similar regarding age (39.8 ± 13.7 vs. 44.8 ± 16.2 years,p = 0.192), total burn size (3.1 ± 2.3 vs. 3.4 ± 2.8 %TBSA,p = 0.721) and treated wound size (1.9 ± 1.2 vs. 1.5 ± 0.8 %TBSA,p = 0.138). We found no differences regarding healing time (11.0 ± 4.9 vs. 8.6 ± 3.8,p = 0.074, and significant differences in a number of dressing changes throughout the study (2.4 ± 1.5 vs 4.2 ± 1.9,p < 0.001). The Kaplan-Meier time-to-event analysis exhibited no statistically significant difference in the time to healing or skin grafting (p = 0.085) in NPWT group compared with SOC group. The median time to healing or skin grafting was 10(8-11) days for NPWT and 9(7-11) days for SOC. The hazard ratio for healing or skin graft was HR= 0.64(0.38-1.08). The results of the time-to-event analysis as well as the Kaplan-Meier curve on the PPS confirmed this result. We found no differences in secondary surgical operations 15.2 vs 21.4 % pain or functional outcomes. CONCLUSIONS: In this study, we found no significant difference between the two groups in terms of time to detect wound healing. We also found no difference regarding further operations for wound closure, pain and/or scarring. However, dressing changes were significantly less frequent for patients that were treated with NPWT, which may be a psychological and logistical advantage.

Retrograde Intrarenal Surgery for Lithiasis Using Suctioning Devices: A Shift in Paradigm?

New suction endoscopes, ureteral access sheaths (UAS) and catheters aim to improve the efficacy of flexible ureteroscopy and optimize its safety. Suction UAS with non-flexible tips have shown promising results, especially in maintaining low intrarenal pressure, but also in removing small debris and reducing the "snow globe" effect. In addition, suctioning UAS with a flexible tip offers the advantage of being able to be navigated through the pyelocaliceal system to where the laser lithotripsy is performed. It can also remove small stone fragments when the flexible ureteroscope is retracted, using the Venturi effect. Direct in-scope suction (DISS) involves aspirating dust and small stone debris through the working channel of a flexible ureteroscope, thus regulating intrarenal pressure and improving visibility. Steerable aspiration catheters are other devices designed to increase stone clearance of the pyelocaliceal system. They are inserted under fluoroscopic guidance into every calyx after retraction of the flexible ureteroscope, alternating irrigation and aspiration to remove dust and small gravels. Combining flexible-tip suction UAS and the DISS technique may offer some advantages worth evaluating. The advantage of using these instruments to achieve a low intrarenal pressure was demonstrated. The true practical impact on the long-term stone-free status is a matter requiring further studies.