Risk of major postoperative complications in breast reconstructive surgery with and without an acellular dermal matrix; Development of a prognostic prediction model

Introduction

Acellular dermal matrices (ADM) have been suggested to allow for different approaches and reduce the risk of postoperative complications in implant-based breast surgery. Surgeons seem to embrace ADMs around the world, although a lack of consistent evidence regarding the factors that increase the risk of major postoperative complications remains.

Purpose

To develop and internally validate a model to predict the risk of a major postoperative complication in breast reconstructive surgery with and without an ADM.

Methodology

The DBIR is an opt-out registry that holds characteristics of all breast implant surgeries in the Netherlands since 2015. Using a literature-driven preselection of predictors, multivariable mixed-effects logistic regression modelling was used to develop the prediction model.

Results

A total of 2939 breasts were eligible, of which 11% underwent an ADM-assisted procedure (single-stage or two-stage). However, 31% underwent a two-stage procedure (with or without the use of ADM). Of all breasts, 10.2% developed a major postoperative complication. Age (OR 1.01), delayed timing (OR 0.71), and two-stage technique (OR 4.46) were associated with the outcome.

Conclusion

The data suggest that ADM use was not associated with a major postoperative complication, while two-stage reconstructions were strongly associated with an increased risk of major complications. Despite these findings, ADMs are not as popular in the Netherlands as in the USA. The predictive capabilities of the developed model are mediocre to poor, but because of the above findings, we believe that the role of the two-stage technique as a golden standard should be put up for debate.

Towards evidence based plastic surgery; how a national research agenda can unite research

We describe the development of the Research Agenda of the Dutch Society for Plastic Surgery, supported and democratically created by plastic surgeons, patients, and other stakeholders. The agenda contains the 10 most relevant knowledge gaps encountered in clinical practice, as prioritized by the abovementioned groups. The aim is to stimulate national collaborations and research networks to initiate trials to answer these knowledge gaps. The agenda will be renewed periodically to stay relevant. We encourage other national and international associations to develop a research agenda within their field, and intensify their research network and improve research quality.

Meta-analysis of the oncological safety of autologous fat transfer after breast cancer

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Predictors of complications after direct-to-implant breast reconstruction with an acellular dermal matrix from a multicentre randomized clinical trial

BACKGROUND

In the multicentre randomized trial BRIOS (Breast Reconstruction In One Stage), direct-to-implant (DTI) breast reconstruction with an acellular dermal matrix (ADM) was associated with a markedly higher postoperative complication rate compared with two-stage tissue expander/implant breast reconstruction. This study aimed to identify factors that contribute to the occurrence of complications after DTI ADM-assisted breast reconstruction.

METHODS

Data were obtained from the BRIOS study, including all patients treated with DTI ADM-assisted breast reconstruction. Logistic regression analyses were performed to identify factors predictive of postoperative complications.

RESULTS

Fifty-nine patients (91 breasts) were included, of whom 27 (35 breasts) developed a surgical complication. Reoperations were performed in 29 breasts (32 per cent), with prosthesis removal in 22 (24 per cent). In multivariable analyses, mastectomy weight was associated with complications (odds ratio (OR) 1·94, 95 per cent c.i. 1·33 to 2·83), reoperations (OR 1·70, 1·12 to 2·59) and removal of the implant (OR 1·55, 1·11 to 2·17). Younger patients (OR 1·07, 1·01 to 1·13) and those who received adjuvant chemotherapy (OR 4·83, 1·15 to 20·24) more frequently required reoperation. In univariable analyses, adjuvant radiotherapy showed a trend towards more complications (OR 7·23, 0·75 to 69·95) and removal of the implant (OR 5·12, 0·76 to 34·44), without reaching statistical significance.

CONCLUSION

Breast size appeared to be the most significant predictor of complications in DTI ADM-assisted breast reconstruction. The technique should preferably be performed in patients with small to moderate sized breasts. Registration number: NTR5446 ( http://www.trialregister.nl).

Understanding the effects of time on collaborative learning processes in problem based learning: a mixed methods study

Little is known how time influences collaborative learning groups in medical education. Therefore a thorough exploration of the development of learning processes over time was undertaken in an undergraduate PBL curriculum over 18 months. A mixed-methods triangulation design was used. First, the quantitative study measured how various learning processes developed within and over three periods in the first 1,5 study years of an undergraduate curriculum. Next, a qualitative study using semi-structured individual interviews focused on detailed development of group processes driving collaborative learning during one period in seven tutorial groups. The hierarchic multilevel analyses of the quantitative data showed that a varying combination of group processes developed within and over the three observed periods. The qualitative study illustrated development in psychological safety, interdependence, potency, group learning behaviour, social and task cohesion. Two new processes emerged: 'transactive memory' and 'convergence in mental models'. The results indicate that groups are dynamic social systems with numerous contextual influences. Future research should thus include time as an important influence on collaborative learning. Practical implications are discussed.

Visualising the invisible: a network approach to reveal the informal social side of student learning

World-wide, universities in health sciences have transformed their curriculum to include collaborative learning and facilitate the students' learning process. Interaction has been acknowledged to be the synergistic element in this learning context. However, students spend the majority of their time outside their classroom and interaction does not stop outside the classroom. Therefore we studied how informal social interaction influences student learning. Moreover, to explore what really matters in the students learning process, a model was tested how the generally known important constructs-prior performance, motivation and social integration-relate to informal social interaction and student learning. 301 undergraduate medical students participated in this cross-sectional quantitative study. Informal social interaction was assessed using self-reported surveys following the network approach. Students' individual motivation, social integration and prior performance were assessed by the Academic Motivation Scale, the College Adaption Questionnaire and students' GPA respectively. A factual knowledge test represented student' learning. All social networks were positively associated with student learning significantly: friendships (β = 0.11), providing information to other students (β = 0.16), receiving information from other students (β = 0.25). Structural equation modelling revealed a model in which social networks increased student learning (r = 0.43), followed by prior performance (r = 0.31). In contrast to prior literature, students' academic motivation and social integration were not associated with students' learning. Students' informal social interaction is strongly associated with students' learning. These findings underline the need to change our focus from the formal context (classroom) to the informal context to optimize student learning and deliver modern medics.

Self-monitoring as a familial vulnerability marker for psychosis: an analysis of patients, unaffected siblings and healthy controls

BACKGROUND

Alterations in self-monitoring have been reported in patients with psychotic disorders, but it remains unclear to what degree they represent true indicators of familial vulnerability for psychosis.

METHOD

An error-correction action-monitoring task was used to examine self-monitoring in 42 patients with schizophrenia, 32 of their unaffected siblings and 41 healthy controls.

RESULTS

Significant between-group differences in self-monitoring accuracy were found (χ2=29.3, p<0.0001), patients performing worst and unaffected siblings performing at an intermediate level compared to controls (all between-group differences p<0.05). In the combined group of healthy controls and unaffected siblings, detection accuracy was associated with positive schizotypy as measured by the Structured Interview for Schizotypy - Revised (SIS-R) (β=-0.16, s.e.=0.07, p=0.026), but not with negative schizotypy (β=-0.05, s.e.=0.12, p=0.694). In patients, psychotic symptoms were not robustly associated with detection accuracy (β=-0.01, s.e.=0.01, p=0.094), although stratified analysis revealed suggestive evidence for association in patients not currently using antipsychotic medication (β=-0.03, s.e.=0.01, p=0.052), whereas no association was found in patients on antipsychotic medication (β=-0.01, s.e.=0.01, p=0.426). A similar pattern of associations was found for negative symptoms.

CONCLUSIONS

Alterations in self-monitoring may be associated with familial risk and expression of psychosis. The association between psychotic symptoms and self-monitoring in patients may be affected by antipsychotic medication, which may explain previous inconsistencies in the literature.

Radiation-induced structural changes in membrane proteins of human erythrocytes and ghosts and the relation to cellular morphology

Isolated human erythrocytes and ghosts were irradiated with X-rays under different experimental conditions. The effect of the radiation treatment was examined with regard to the structure of membrane proteins as well as to the morphology of whole cells and ghosts. From sodium dodecyl sulphate/polyacrylamide gel electrophoresis it is concluded that spectrin (band 1 and 2) is the most radiosensitive of the membrane proteins examined. X-irradiation of cells and ghosts induced covalent cross-linking of a small fraction of membrane proteins. In the protein aggregates thus formed spectrin was found to be the major component. Molecular disulphide (-SS-) bridges seemed to account for part of the cross-links observed. Some nondisulphide cross-links were also found, especially when ghosts were irradiated. Significant amounts of spectrin aggregates were formed during post-irradiation incubation at 37 degrees C but not at 4 degrees C. In the intact cell a transformation in shape from discocyte to echinocyte accompanied the process of post-irradiation spectrin aggregation. The characteristics of both processes, such as their reversibility with adenosine, point to a metabolic involvement. It is shown that there is no causal relationship between the two phenomena observed. The possible cause of the post-irradiation effects and the parallelism with similar processes in nonirradiated metabolically depleted cells is discussed.