Predictor analysis for complications after mandibular reconstruction using microvascular anastomosed bone grafts and CAD / CAM reconstruction plates

Einleitung: CAD/CAM-Rekonstruktionsplatten kommen bei Unterkieferrekonstruktionen vermehrt zum Einsatz. Nur wenige Studien analysieren postoperative Komplikationen nach Transplantation von mikrovaskulär-anastomosierten Knochentransplantaten mit diesem Plat-tentyp. Diese Arbeit soll unabhängige Prädiktoren für Komplikationsraten nach Unterkie-ferrekonstruktion mittels CAD/CAM-Rekonstruktionsplatten identifizieren. Methodik: 64 Patienten, die zwischen April 2017 und März 2019 eine Unterkieferrekonstruk-tion mit einem mikrovaskulären Knochentransplantat und CAD/CAM-Rekonstruktionsplatte erhielten, wurden eingeschlossen. Der Einfluss patienten-, therapie- und rekonstruktionsspezi-fischer Faktoren auf Komplikationen des Weichgewebes, Knochens oder Osteosynthesemate-rials und Transplantatverluste wurde untersucht. Die statistische Auswertung erfolgte sowohl deskriptiv als auch uni- und multivariabel. Ergebnisse: Indikationen waren maligne (60,9%) und benigne Tumore (7,8%), Osteoradio-nekrosen (20,3%) und medikamenten-assoziierte Osteonekrosen (7,8%). Frühe Komplikatio-nen waren Anastomosenrevisionen (10,9%) und frühe Transplantatverluste (6,3%). Späte Komplikationen waren Weichgewebskomplikationen (Wundheilungsstörungen (43,8%), frei-liegendes Osteosynthesematerial (26,6%)), Osteosynthesekomplikationen (Plattenlockerungen (1,6%), Plattenfrakturen (3,2%)), Knochenkomplikationen (Pseudarthrosen (36,5%), postope-rative Osteoradionekrosen (9,4%)) und späte Transplantatverluste (6,3%). Diabetes mellitus konnte als Prädiktor für Pseudarthrosen (p=0,040) ausgemacht werden. Pa-tienten mit der Indikation Osteoradionekrose zeigten signifikant häufiger Wundheilungsstö-rungen (p=0,007) und einen nicht-signifikanten Trend für vermehrte Pseudarthrosen (p=0,270). Radiotherapie war ein signifikanter Prädiktor für die Entstehung von Wundheilungsstörungen (p=0,011) und unzureichender Verknöcherung (p=0,001). Tumorpatienten des Stadium pT4 (p=0,008) zeigten signifikant häufiger unzureichende Verknöcherungen. Fibulatransplantate (p=0,025) zeigten signifikant seltener insuffiziente ossäre Konsolidierun-gen als die Becken- oder Skapulatransplantate. Schlussfolgerung: CAD/CAM-Rekonstruktionsplatten scheinen im Vergleich zur Literatur zu keinen erhöhten Raten an Weichteil- oder Osteosynthesekomplikationen zu führen, können diese aber auch nicht reduzieren. Insbesondere Radiotherapien und die Indikation Osteoradi-onekrose sind mit hohen Raten an Wundheilungsstörungen assoziiert, sodass bei diesem Patientenkollektiv Verbesserungen angestrebt werden sollten. Allgemein erhöhte Raten an Pseudarthrosen bei CAD/CAM-Rekonstruktionsplatten können nicht festgestellt werden. Der Einfluss der höheren Steifigkeit dieses Plattentyps auf eine reduzierte Spaltossifikation kann nicht ausgeschlossen werden. Erhöhten Raten an Pseudarthrosen bei Patienten mit der Indikation Osteoradionekrose geben einen Hinweis darauf, dass eventuell umfangreichere initiale Resektionen bei diesen Patienten notwendig wären.Introduction: CAD/CAM titanium reconstruction plates are increasingly used for mandible reconstruction. So far there are only few studies analyzing postoperative complications after free flap reconstruction with these plates. As part of this work, independent predictors for postoperative complications after using CAD/CAM reconstruction plates were identified. Material and methods: 64 patients with free flap mandible reconstruction and CAD/CAM reconstruction plates between April 2017 and March 2019 were included. Patient-specific, therapy-specific and reconstruction-specific factors were determined and their influence on the complication rates of soft tissue, bone or osteosynthesis material and on flap loss was investigated. Descriptive, univariate and multivariate statistical analysis was performed. Results: Indications for mandibular reconstruction included malignant (60.9%) and benign tumors (7.8%), osteoradionecrosis (20.3%) and drug-associated osteonecrosis (7.8%). Early complications were anastomosis revisions (10.9%) and early flap losses (6.3%). Late complications were soft tissue complications (wound healing disorders (43.8%), exposed oste-osynthesis material (26.6%)), osteosynthesis complications (plate loosening (1.6%), plate frac-tures (3.2%)), bone complications (pseudarthrosis (36.5%), postoperative osteoradionecrosis (9.4%)) and late flap losses (6.3%). An independent patient-specific predictor for pseudarthrosis was diabetes mellitus (p=0.040). Patients with the resection indication osteoradionecrosis showed significantly higher rates of wound healing disorders (p=0.007) and a non-significant trend for increased non-unions (p=0.270). A significant therapy-specific predictor was radiotherapy (adjuvant or anamnestic) for wound healing disorders (p = 0.011) and inadequate ossification (p=0.001). Tumor patients of the stage pT4 (p=0.008) showed inadequate ossification significantly more often. Regarding reconstruction-specific factors, fibular transplants (p=0.025) showed insufficient osseous consolidations significantly less often than the comparison groups. Conclusion: CAD / CAM reconstruction plates do not seem to lead to increased rates of soft tissue or osteosynthesis complications compared to the results in the literature, but they cannot reduce them either. High rates of wound healing disorders in this study are likely primarily due to factors such as osteoradionecrosis as resection indication and radiotherapy. CAD/CAM re-construction plates do not lead to higher rates of pseudarthrosis. The participation of CAD/CAM reconstruction plates in high rates of pseudarthrosis due to their high rigidity can-not be ruled out. The increased rates of pseudarthrosis in patients with the indication for resection of osteoradi-onecrosis indicate that more extensive resections may be necessary in these patients

Impact of the adjacent bone on pseudarthrosis in mandibular reconstruction with fibula free flaps

Abstract Background Mechanical and morphological factors have both been described to influence the rate of pseudarthrosis in mandibular reconstruction. By minimizing mechanical confounders, the present study aims to evaluate the impact of bone origin at the intersegmental gap on osseous union. Methods Patients were screened retrospectively for undergoing multi-segment fibula free flap reconstruction of the mandible including the anterior part of the mandible and osteosynthesis using patient-specific 3D-printed titanium reconstruction plates. Percentage changes in bone volume and width at the bone interface between the fibula/fibula and fibula/mandible at the anterior intersegmental gaps within the same patient were determined using cone-beam computed tomography (CBCT). Additionally, representative samples of the intersegmental zones were assessed histologically and using micro-computed tomography (µCT). Results The bone interface (p = 0.223) did not significantly impact the change in bone volume at the intersegmental gap. Radiotherapy (p < 0.001), time between CBCT scans (p = 0.006) and wound healing disorders (p = 0.005) were independent risk factors for osseous non-union. Preliminary analysis of the microstructure of the intersegmental bone did not indicate morphological differences between fibula–fibula and fibula–mandible intersegmental bones. Conclusions The bone interface at the intersegmental gap in mandibular reconstruction did not influence long-term bone healing significantly. Mechanical and clinical properties seem to be more relevant for surgical success

Prospective observational cohort study on grading the severity of postoperative complications in global surgery research

Background The Clavien–Dindo classification is perhaps the most widely used approach for reporting postoperative complications in clinical trials. This system classifies complication severity by the treatment provided. However, it is unclear whether the Clavien–Dindo system can be used internationally in studies across differing healthcare systems in high- (HICs) and low- and middle-income countries (LMICs). Methods This was a secondary analysis of the International Surgical Outcomes Study (ISOS), a prospective observational cohort study of elective surgery in adults. Data collection occurred over a 7-day period. Severity of complications was graded using Clavien–Dindo and the simpler ISOS grading (mild, moderate or severe, based on guided investigator judgement). Severity grading was compared using the intraclass correlation coefficient (ICC). Data are presented as frequencies and ICC values (with 95 per cent c.i.). The analysis was stratified by income status of the country, comparing HICs with LMICs. Results A total of 44 814 patients were recruited from 474 hospitals in 27 countries (19 HICs and 8 LMICs). Some 7508 patients (16·8 per cent) experienced at least one postoperative complication, equivalent to 11 664 complications in total. Using the ISOS classification, 5504 of 11 664 complications (47·2 per cent) were graded as mild, 4244 (36·4 per cent) as moderate and 1916 (16·4 per cent) as severe. Using Clavien–Dindo, 6781 of 11 664 complications (58·1 per cent) were graded as I or II, 1740 (14·9 per cent) as III, 2408 (20·6 per cent) as IV and 735 (6·3 per cent) as V. Agreement between classification systems was poor overall (ICC 0·41, 95 per cent c.i. 0·20 to 0·55), and in LMICs (ICC 0·23, 0·05 to 0·38) and HICs (ICC 0·46, 0·25 to 0·59). Conclusion Caution is recommended when using a treatment approach to grade complications in global surgery studies, as this may introduce bias unintentionally

The surgical safety checklist and patient outcomes after surgery: a prospective observational cohort study, systematic review and meta-analysis

© 2017 British Journal of Anaesthesia Background: The surgical safety checklist is widely used to improve the quality of perioperative care. However, clinicians continue to debate the clinical effectiveness of this tool. Methods: Prospective analysis of data from the International Surgical Outcomes Study (ISOS), an international observational study of elective in-patient surgery, accompanied by a systematic review and meta-analysis of published literature. The exposure was surgical safety checklist use. The primary outcome was in-hospital mortality and the secondary outcome was postoperative complications. In the ISOS cohort, a multivariable multi-level generalized linear model was used to test associations. To further contextualise these findings, we included the results from the ISOS cohort in a meta-analysis. Results are reported as odds ratios (OR) with 95% confidence intervals. Results: We included 44 814 patients from 497 hospitals in 27 countries in the ISOS analysis. There were 40 245 (89.8%) patients exposed to the checklist, whilst 7508 (16.8%) sustained ≥1 postoperative complications and 207 (0.5%) died before hospital discharge. Checklist exposure was associated with reduced mortality [odds ratio (OR) 0.49 (0.32–0.77); P\u3c0.01], but no difference in complication rates [OR 1.02 (0.88–1.19); P=0.75]. In a systematic review, we screened 3732 records and identified 11 eligible studies of 453 292 patients including the ISOS cohort. Checklist exposure was associated with both reduced postoperative mortality [OR 0.75 (0.62–0.92); P\u3c0.01; I2=87%] and reduced complication rates [OR 0.73 (0.61–0.88); P\u3c0.01; I2=89%). Conclusions: Patients exposed to a surgical safety checklist experience better postoperative outcomes, but this could simply reflect wider quality of care in hospitals where checklist use is routine

Critical care admission following elective surgery was not associated with survival benefit: prospective analysis of data from 27 countries

This was an investigator initiated study funded by Nestle Health Sciences through an unrestricted research grant, and by a National Institute for Health Research (UK) Professorship held by RP. The study was sponsored by Queen Mary University of London