Duplex Analysis of Cannulated Vessels in Peripheral Veno-Arterial Extracorporeal Membrane Oxygenation.

Background and objectives: Veno-arterial extracorporeal membrane oxygenation (V-A ECMO) cannulas have major repercussions on vascular hemodynamics that can potentially lead to limb ischemia. Duplex ultrasound enables the non-invasive analysis of vascular hemodynamics. This study aims to describe the duplex parameters of the femoral vessels during V-A ECMO support, investigate differences between cannulated and non-cannulated vessels, and analyze the variations in the case of limb ischemia and intra-aortic balloon pumps (IABPs). Methods: Nineteen adults (≥18 years), supported with femoro-femoral V-A ECMO, underwent a duplex analysis of the superficial femoral arteries (SFAs) and veins (FVs). Measured parameters included flow velocities, waveforms, and vessel diameters. Results: 89% of patients had a distal perfusion cannula during duplex analysis and 21% of patients developed limb ischemia. The mean peak systolic flow velocity (PSV) and end-diastolic flow velocity (EDV) of the SFAs on the cannulated side were, respectively, 42.4 and 21.4 cm/s. The SFAs on the non-cannulated side showed a mean PSV and EDV of 87.4 and 19.6 cm/s. All SFAs on the cannulated side had monophasic waveforms, whereas 63% of the SFAs on the non-cannulated side had a multiphasic waveform. Continuous/decreased waveforms were seen in 79% of the FVs on the cannulated side and 61% of the waveforms of the contralateral veins were respirophasic. The mean diameter of the FVs on the cannulated side, in patients who developed limb ischemia, was larger compared to the FVs on the non-cannulated side with a ratio of 1.41 ± 0.12. The group without limb ischemia had a smaller ratio of 1.03 ± 0.25. Conclusions: Femoral cannulas influence flow velocities in the cannulated vessels during V-A ECMO and major waveforms alternations can be seen in all SFAs on the cannulated side and most FVs on the cannulated side. Our data suggest possible venous stasis in the FV on the cannulated side, especially in patients suffering from limb ischemia.

Use of covered stent grafts as treatment of traumatic venous injury to the inferior vena cava and iliac veins: A systematic review.

OBJECTIVE: Venous injury to the inferior vena cava or iliac veins is rare but can result in high mortality rates. Traditional treatment by repair or ligation can be technically demanding. A relatively new treatment modality is the use of a covered stent to cover the venous defect. The aim of the present systematic review was to assess the techniques, results, and challenges of covered stent graft repair of traumatic injury to the inferior vena cava and iliac veins. METHODS: The PubMed (Medline) and Embase databases were systematically searched up to September 2020 by two of us (R.R.S. and D.D.) independently for studies reporting on covered stenting of the inferior vena cava or iliac veins after traumatic or iatrogenic injury. A methodologic quality assessment was performed using the modified Newcastle-Ottawa scale. Data were extracted for the following parameters: first author, year of publication, study design, number of patients, type and diameter of the stent graft, hemostatic success, complications, mortality, postoperative medication, follow-up type and duration, and venous segment patency. The main outcome was clinical success of the intervention, defined as direct hemostasis, with control of hemorrhage, hemodynamic recovery, and absence of contrast extravasation. RESULTS: From the initial search, which yielded 1884 records, a total of 28 studies were identified for analysis. All reports consisted of case reports, except for one retrospective cohort study and one case series. A total of 35 patients had been treated with various covered stent grafts, predominantly thoracic or abdominal aortic endografts. In all patients, the treatment was technically successful. The 30-day mortality rate for the entire series was 2.9%. Three perioperative complications were described: one immediate stent occlusion, one partial thrombosis, and one pulmonary embolism. Additional in-stent thrombus formation was seen during follow-up in three patients, leading to one stent graft occlusion (asymptomatic). The postoperative anticoagulation strategy was highly heterogeneous. The median follow-up was 3 months (range, 0.1-84 months). However, follow-up with imaging studies was not performed in all cases. CONCLUSIONS: In selected cases of injury to the inferior vena cava and iliac veins, covered stent grafts can be successful for urgent hemostasis with good short-term results. Data on long-term follow-up are very limited.

The disappointing quality of published studies on operative techniques for rectovaginal fistulas: a blueprint for a prospective multi-institutional study.

BACKGROUND: Treatment of rectovaginal fistulas is difficult, and many surgical interventions have been developed. The best surgical intervention for the closure of these fistulas is still unclear. OBJECTIVE: A systematic review was performed reporting the outcomes of different surgical techniques for rectovaginal fistulas. DATA SOURCES: Medline (PubMed, Ovid), Embase (Ovid), and The Cochrane Library databases were searched for eligible articles as well as the references of these articles. STUDY SELECTION: Two independent reviewers analyzed the search results for eligible articles based on title, abstract, and described results. INTERVENTION(S): Any surgical intervention for the closure of rectovaginal fistulas was included. MAIN OUTCOME MEASURES: The main outcome was closure rate. Secondary outcomes were quality of life, morbidity, and the effect on sexual functioning. RESULTS: Many articles with different operative techniques were identified and classified in the following categories: advancement flaps (endorectal and endovaginal), transperineal closure, Martius procedure, gracilis muscle transposition, rectal resections, transabdominal closure, mesh repair, plugs, endoscopic repairs, closure with biomaterials, and miscellaneous techniques. Results vary widely with closure rates between 0% and >80%. None of the studies were randomized. Because of the poor quality of the identified studies, the comparison of results and performance of a meta-analysis were not possible.Data regarding the secondary outcomes were mostly unavailable. LIMITATIONS: The major limitation of this review was the limited availability of high-quality prospective studies, making it impossible to perform a meta-analysis. CONCLUSIONS: No conclusion about the best surgical intervention for rectovaginal fistulas could be formulated. More large studies of high quality are needed to find the best treatment for rectovaginal fistulas. A design for these high-quality studies was formulated.

Long-term results of mucosal advancement flap combined with platelet-rich plasma for high cryptoglandular perianal fistulas.

BACKGROUND: The long-term closure rate of high perianal fistulas after surgical treatment remains disappointing. OBJECTIVE: The goal of this study was to improve the long-term closure rate of high cryptoglandular perianal fistulas combining mucosal advancement flap with platelet-rich plasma. DESIGN: This study was retrospective in design. SETTING: This study was conducted at 2 secondary and 1 tertiary referral hospitals. PATIENTS: Patients presenting with high cryptoglandular perianal fistulas involving the middle/upper third of the anal sphincter complex were included. INTERVENTIONS: A staged surgical treatment was performed; After seton placement, a mucosal advancement flap was combined with platelet-rich plasma. MAIN OUTCOME MEASURES: Recurrence was the main outcome. Incontinence was the secondary outcome. RESULTS: We operated on 25 patients between 2006 and 2012. Thirteen (52%) patients had previous fistula surgery. The median follow-up period was 27 months. One patient (4.0%) was lost to follow-up after 4 months. Freedom from recurrence at 2 years was 0.83 (95% CI, 0.62-0.93). Two of the 4 patients with a recurrence (8%) had a repeated treatment and healed. One patient (4.0%) refused another treatment, but agreed to stay in follow-up. One patient (4.0%) requested a colostomy, resulting in closure of the fistula. Complications occurred in 1 patient (4.0%). Incontinence numbers were low with a median Vaizey score of 3.0 out of a maximum of 24. LIMITATIONS: The study was limited by its retrospective design, lack of preoperative incontinence data, selection bias, and phone interview follow-up. CONCLUSION: The long-term outcome results of patients with primary and recurrent high cryptoglandular perianal fistulas treated with a seton followed by mucosal advancement flap and platelet-rich plasma show low recurrence, complication, and incontinence rates. Therefore, this technique seems to be a valid option as treatment. Larger and preferably randomized controlled studies are needed to further explore this surgical technique.