Abdominal donor-site complications following autologous breast reconstruction: A multi-institutional multisurgeon study

BACKGROUND

The deep inferior epigastric perforator (DIEP) free flap is the gold standard procedure for autologous breast reconstruction. Although breast-related complications have been well described, donor-site complications and contributing patient risk factors are poorly understood.

METHODS

We examined a multi-institutional, prospectively maintained database of patients undergoing DIEP free flap breast reconstruction between 2015 and 2020. We evaluated patient demographics, operative details, and abdominal donor-site complications. Logistic regression modeling was used to predict donor-site outcomes based on patient characteristics.

RESULTS

A total of 661 patients were identified who underwent DIEP free flap breast reconstruction across multiple institutions. Using logistic regression modeling, we found that body mass index (BMI) was an independent risk factor for umbilical complications (odds ratio [OR] 1.11, confidence interval [CI] 1.04-1.18, p = 0.001), seroma (OR 1.07, CI 1.01-1.13, p = 0.003), wound dehiscence (OR 1.10, CI 1.06-1.15, p = 0.001), and surgical site infection (OR 1.10, CI 1.05-1.15, p = 0.001) following DIEP free flap breast reconstruction. Further, immediate reconstruction decreases the risk of abdominal bulge formation (OR 0.22, CI 0.108-0.429, p = 0.001). Perforator selection was not associated with abdominal morbidity in our study population.

CONCLUSIONS

Higher BMI is associated with increased abdominal donor-site complications following DIEP free flap breast reconstruction. Efforts to lower preoperative BMI may help decrease donor-site complications.

The heart of it all: Body dysmorphic disorder in cosmetic surgery

BACKGROUND

Body Dysmorphic Disorder (BDD) represents a prevalent mental health condition characterized by distress arising from self-perceived physical imperfections. BDD serves as a contraindication to aesthetic surgery. Recognizing BDD holds paramount importance for plastic surgeons, as it is instrumental in averting the exacerbation of this condition while ensuring appropriate referrals.

OBJECTIVE

This study aimed to investigate the prevalence of BDD in cosmetic surgery patients and to pinpoint key characteristics associated with BDD. This information provides plastic surgeons with specific factors to consider during preoperative evaluations.

METHODS

We employed TriNetX database to identify patients with BDD who underwent cosmetic surgery identified by Current Procedural Terminology codes. Demographics and patient characteristics were identified using the International Classification of Diseases 10 codes. We calculated odds ratios (OR) by using chi-squared tests to assess risk factors among patients with BDD.

RESULTS

Of 226,374 patients who underwent plastic surgery between August 2002 and August 2022, fewer than 0.1% were diagnosed with BDD. Of the BDD patients, 52.1% were diagnosed after cosmetic surgery. Compared with the control group, BDD patients were more likely to undergo rhinoplasty (OR=1.784, p = 0.004) and nonlocalized lipectomy (OR=1.448, p = 0.021) and less likely to undergo blepharoplasty (OR=0.451, p = 0.002). Findings indicated a strong association between BDD patients undergoing cosmetic procedures and comorbid psychiatric conditions such as depression (OR=4.279, p < 0.05), anxiety (OR=5.490, p < 0.05), and Attention-Deficit Hyperactivity Disorder (OR=3.993, p < 0.05).

CONCLUSIONS

These findings underscore the ongoing significance of BDD in the context of cosmetic surgery, potentially indicating a lower surgery rate among BDD patients compared with previous estimates. Nevertheless, avenues for further improvement persist. Our data affirm the noteworthy occurrence of postsurgery BDD development, thereby highlighting the ongoing necessity for psychiatric evaluation in surgical patients.

Analysis of Postoperative Distal Radius Fracture Outcomes in the Setting of Osteopenia and Osteoporosis for Patients with Comorbid Conditions

Purpose

Distal radius fractures (DRFs) are among the most common orthopedic injuries, especially in the elderly. A wide variety of approaches have been advocated as successful treatment modalities; yet, there remains variability in practice patterns of DRF in patients with osteoporosis and osteopenia. Using large data set analysis, we sought to determine the risk profile of operative fixation of DRF in patients with low bone mineral density.

Methods

A commercially available health care database, PearlDiver, was queried for all patients who underwent open reduction internal fixation of DRFs between 2010 and 2020. The study population was divided into groups based on the presence or absence of osteopenia or osteoporosis and was further classified by patients who were receiving bisphosphonate therapy. Complication rates were calculated, including rates of malunion, surgical site infection, osteomyelitis, hardware failure, and hardware removal. Five-year future fragility fractures were defined in hip, vertebrae, humerus, and wrist fractures. Chi-square analysis and logistic regression were performed to determine an association between these comorbidities and various postoperative complications.

Results

A total of 152,926 patients underwent open reduction internal fixation of a DRF during the study period. Chi-square analysis of major complications at 3 months showed a statistically significant increase in malunion in patients with osteopenia (P = .05) and patients with osteoporosis (P = .05) who underwent open reduction internal fixation. Logistic regression analysis at 12 months after surgery demonstrated that osteopenia was associated with an increased risk of hardware failure (P < .0001), hardware removal (P < .0001), surgical site infection (P < .0001), and malunion (P = .004). Osteoporosis was associated with a significantly increased risk of hardware failure (P = .01), surgical site infection (P < .0001), and malunion (P < .0001).

Conclusions

We demonstrated, using large data set analysis, that DRF patients with osteopenia and osteoporosis are predicted to be at increased risk of multiple postoperative complications, and thus, bone density should be strongly considered in treatment planning for these patients.

Type of study/level of evidence

Prognostic III.

Venous Thromboembolism after Deep Inferior Epigastric Perforator Flap Breast Reconstruction: Review of Outcomes After a Postoperative Prophylaxis Protocol

BACKGROUND

Deep inferior epigastric perforator (DIEP) flap breast reconstruction is among the higher-risk patient groups for venous thromboembolism (VTE) in plastic surgery. Surgeons often opt for a patient-specific approach to postoperative anticoagulation, and the field has yet to come to a consensus on VTE chemoprophylaxis regimens.

METHODS

A new chemoprophylaxis protocol was introduced starting March 2019 that involved two weeks of treatment with enoxaparin, regardless of patient risk factors. A retrospective chart review was conducted on all patients who underwent DIEP flap breast reconstruction at our institution between January 2014 and March 2020. Patients were grouped based on whether they enrolled in the new VTE protocol in the postoperative period or not. Patient demographics, prophylaxis type, and outcomes data were recorded, retrospectively. The primary outcome measure was postoperative VTE incidence.

RESULTS

Risk of VTE was significantly higher in patients discharged without VTE prophylaxis compared to patients discharged with prophylaxis (3.7% vs. 0%, p = 0.03). Notably, zero patients in the VTE prophylaxis group developed a DVT or PE. Additionally, the risk of a VTE event was 25 times greater in patients with a Caprini score greater than or equal to 6 (p=0.0002).

CONCLUSIONS

We demonstrate the successful implementation of a two-week VTE chemoprophylaxis protocol in DIEP flap breast reconstruction patients that significantly reduces the rate of VTE while not affecting the rate of hematoma complications.

Addressing Surgical Instrument Oversupply: A Focused Literature Review and Case-Study in Orthopedic Hand Surgery

BACKGROUND

Instrument oversupply drives cost in the operating room (OR). We review previously reported methodologies for surgical instrument reduction and report a pilot methodology for optimizing instrument supply via ethnographic instrument tracking of thumb carpometacarpal (CMC) arthroplasties. Additionally, we report a cost analysis of instrument oversupply and potential savings of tray optimization methods.

METHODS

Instrument utilization was tracked over 8 CMC arthroplasties conducted by 2 surgeons at an ambulatory surgery center of a large academic hospital. An optimized supply methodology was designed. A cost analysis was conducted using health-system-specific data and previously published research.

RESULTS

After tracking instrument use in 8 CMC arthroplasties, a cumulative total of 59 out of the 120 instruments in the Hand & Foot (H&F) tray were used in at least 1 case. Two instruments were used in all cases, and another 20 instruments were used in at least 50% of the cases. Using a reduced tray with 59 instruments, potential cost savings for tray reduction in 60 cases were estimated to be $2086 without peel-packing and $2356 with peel-packing. The estimated cost savings were lower than those reported in literature due to a reduced scope and exclusion of OR time cost in the analysis.

CONCLUSIONS

Instrument oversupply drives cost at our institution's ambulatory surgery center. Ethnography is a cost-effective method to track instrument utilization and determine optimal tray composition for small services but is not scalable to large health systems. The time and cost required to observe sufficient surgeries to enable supply reduction to motivate the need for more efficient methods to determine instrument utility.

Measuring intraoperative surgical instrument use with radio-frequency identification

Objective

Surgical instrument oversupply drives cost, confusion, and workload in the operating room. With an estimated 78%–87% of instruments being unused, many health systems have recognized the need for supply refinement. By manually recording instrument use and tasking surgeons to review instrument trays, previous quality improvement initiatives have achieved an average 52% reduction in supply. While demonstrating the degree of instrument oversupply, previous methods for identifying required instruments are qualitative, expensive, lack scalability and sustainability, and are prone to human error. In this work, we aim to develop and evaluate an automated system for measuring surgical instrument use.

Materials and Methods

We present the first system to our knowledge that automates the collection of real-time instrument use data with radio-frequency identification (RFID). Over 15 breast surgeries, 10 carpometacarpal (CMC) arthroplasties, and 4 craniotomies, instrument use was tracked by both a trained observer manually recording instrument use and the RFID system.

Results

The average Cohen’s Kappa agreement between the system and the observer was 0.81 (near perfect agreement), and the system enabled a supply reduction of 50.8% in breast and orthopedic surgery. Over 10 monitored breast surgeries and 1 CMC arthroplasty with reduced trays, no eliminated instruments were requested, and both trays continue to be used as the supplied standard. Setup time in breast surgery decreased from 23 min to 17 min with the reduced supply.

Conclusion

The RFID system presented herein achieves a novel data stream that enables accurate instrument supply optimization.

875 Using Stress Testing to Identify Vulnerabilities in Artificial Intelligence Models for the Identification of Culprit Carotid Lesions in Cerebrovascular Events

Introduction

Carotid atherosclerosis is a major risk factor for ischaemic stroke, a leading cause of death. Carotid CT angiography (CTA) is commonly performed following a stroke or transient ischaemic attack (TIA) to help guide patient management in secondary prevention of stroke. Deep learning algorithms can help extract greater information from scans.

Method

The dataset comprised CTA scans from 40 culprit and 40 non-culprit carotid arteries of patients with recent stroke/TIA, and 40 carotid arteries of asymptomatic patients without previous stroke/TIA. A 3D convolutional neural network was trained to classify carotid artery type. Each input comprised 14 axial CTA carotid patches (centred around the carotid artery) concatenated together to form a 3D volume (capturing ∼3cm of artery). 75% of the dataset was used for training and 25% for internal validation. Following training, computer vision operations were applied to input images to assess their impact on the model’s classification decisions.

Results

The model achieved 100% accuracy on the training set and 67% on the internal validation set. However, after subjecting input images to image operations, vulnerabilities in the deep learning model were revealed, even when using input images from the training set. For example, using a Gaussian blur filter with sigma 1.0 was sufficient to change classification decisions, as was horizontally flipping the image.

Conclusions

Deep learning has exceptional capabilities for learning, however the risk with such high-capacity models is failure to learn relevant features from the data. Stress testing provides a viable method to further evaluate deep learning models before clinical deployment.

The Effect of Lavender Oil on Perioperative Pain, Anxiety, Depression, and Sleep after Microvascular Breast Reconstruction: A Prospective, Single-Blinded, Randomized, Controlled Trial

BACKGROUND

 Psychosocial distress, depression, or anxiety can occur in up to 50% of women after a breast cancer diagnosis and mastectomy. The purpose of this study was to assess the potential benefit of lavender oil as a perioperative adjunct to improve anxiety, depression, pain, and sleep in women undergoing microvascular breast reconstruction.

METHODS

 This was a prospective, single-blinded, randomized, controlled trial of 49 patients undergoing microvascular breast reconstruction. Patients were randomized to receive lavender oil or placebo (coconut oil) throughout their hospitalization. The effect of lavender oil on perioperative stress, anxiety, depression, sleep, and pain was measured using the hospital anxiety and depression scale, Richards-Campbell Sleep Questionnaire, and the visual analogue scale.

RESULTS

 Twenty-seven patients were assigned to the lavender group and 22 patients were assigned to the control group. No significant differences were seen in the perioperative setting between the groups with regard to anxiety (p = 0.82), depression (p = 0.21), sleep (p = 0.86), or pain (p = 0.30) scores. No adverse events (i.e., allergic reaction) were captured, and no significant differences in surgery-related complications were observed. When evaluating the entire cohort, postoperative anxiety scores were significantly lower than preoperative scores (p < 0.001), while depression scores were significantly higher postoperatively as compared with preoperatively (p = 0.005).

CONCLUSION

 In the setting of microvascular breast reconstruction, lavender oil and aromatherapy had no significant adverse events or complications; however, there were no measurable advantages pertaining to metrics of depression, anxiety, sleep, or pain as compared with the control group.

The Influence of Fat Grafting on Breast Imaging after Postmastectomy Reconstruction: A Matched Cohort Analysis

BACKGROUND

Fat grafting to the reconstructed breast may result in the development of benign lesions on physical examination, prompting further investigation with imaging and biopsy. The aim of this study was to assess the influence of fat grafting on the incidence of imaging and biopsies after postmastectomy reconstruction.

METHODS

Patients who underwent autologous or implant-based reconstruction following mastectomy from 2010 to 2018 were identified. Those receiving fat grafting as part of their reconstructive course were propensity matched 1:1 to those that did not with body mass index, reconstruction timing, and reconstruction type as covariates in a multivariable logistic regression model.

RESULTS

A total of 186 patients were identified, yielding 93 propensity-matched pairs. Fat-grafted patients had higher incidences of palpable masses (38.0 percent versus 18.3 percent; p = 0.003) and postreconstruction imaging (47.3 percent versus 29.0 percent; p = 0.01), but no significant difference in the number of biopsies performed (11.8 percent versus 7.5 percent; p = 0.32). Imaging was predominately interpreted as normal (Breast Imaging-Reporting and Data System 1, 27.9 percent) or benign (Breast Imaging-Reporting and Data System 2, 48.8 percent), with fat necrosis being the most common finding [n = 20 (45.5 percent)]. No demographic, oncologic, reconstructive, or fat grafting-specific variables were predictive of receiving postreconstruction imaging on multivariate analysis. Fat grafting was not associated with decreased 5-year overall survival or locoregional recurrence-free survival.

CONCLUSIONS

Fat grafting to the reconstructed breast is associated with increased incidences of palpable masses and subsequent postreconstruction imaging with benign radiographic findings. Although the procedure is oncologically safe, both patients and providers should be aware that concerning physical examination findings can be benign sequelae of fat grafting and may lead to increased imaging after breast reconstruction.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, III.

A Critical Assessment of the Golden Hour and the Impact of Procedural Timing in Stroke Thrombectomy

BACKGROUND AND PURPOSE

Previous studies in acute ischemic stroke have demonstrated the importance of minimizing delays to endovascular treatment and keeping thrombectomy procedural times at <30-60 minutes. The purpose of this study was to investigate the impact of thrombectomy procedural times on clinical outcomes.

MATERIALS AND METHODS

We retrospectively compared 319 patients having undergone thrombectomy according to procedural time (<30 minutes, 30-60 minutes, and >60 minutes) and time from stroke onset to endovascular therapy (≤6 or >6 hours). Clinical characteristics of patients with postprocedural intracranial hemorrhage were also assessed. Logistic regression was used to determine independent predictors of poor outcome at 90 days (mRS ≥3).

RESULTS

Greater age (OR, 1.03; 95% CI, 1.01-1.06; P = .016), higher admission NIHSS score (OR, 1.10; 95% CI, 1.04-1.16; P = .001), history of diabetes mellitus (OR, 1.96; 95% CI, 1.05-3.65; P = .034), and postprocedural intracranial hemorrhage were independently associated with greater odds of poor outcome. Modified TICI scale scores of 2c (OR, 0.11; 95% CI, 0.04-0.28; P < .001) and 3 (OR, 0.15; 95% CI, 0.06-0.38; P < .001) were associated with reduced odds of poor outcome. Although not statistically significant on univariate analysis, onset to endovascular therapy of >6 hours was independently associated with increased odds of poor outcome (OR, 2.20; 95% CI, 1.11-4.36; P = .024) in the final multivariate model (area under the curve = 0.820). Procedural time was not independently associated with clinical outcome in the final multivariate model (P > .05).

CONCLUSIONS

Thrombectomy procedural times beyond 60 minutes are associated with lower revascularization rates and worse 90-day outcomes. Procedural time itself was not an independent predictor of outcome. While stroke thrombectomy procedures should be performed rapidly, our study emphasizes the significance of achieving revascularization despite the requisite procedural time. However, the potential for revascularization must be weighed against the risks associated with multiple thrombectomy attempts.

Radiomics applied to carotid CT angiograms can identify significant differences between culprit and non-culprit lesions in patients with stroke and transient ischaemic attack

Background

Carotid artery atherosclerosis is an important cause of ischaemic stroke. In oncology, textural analysis (“radiomics”) of computed tomography (CT) images can predict the metastatic potential and prognosis of several types of malignant tumours. We investigated whether this quantitative approach could be applied in carotid artery disease.

Purpose

(1) To evaluate the feasibility of computed tomography angiography (CTA) texture analysis in differentiating symptomatic from asymptomatic patients. (2) To investigate whether CTA carotid texture analysis can identify culprit lesions in patients with stroke and transient ischaemic attack (TIA).

Methods

Carotid CTAs of consented research subjects were included in the study. Symptomatic patients had confirmed carotid artery-related ischaemic stroke or TIA in the 7 days before CTA imaging. Asymptomatic (ASX) patients had no prior stroke/TIA. Both TexRAD, a research texture analysis software, and PyRadiomics, a Python package for radiomics studies, were used to extract 99 first-order and higher-order texture features from regions-of-interest (ROI) drawn around the outer wall of the carotid artery. Single-slice analysis compared the carotid bifurcations of symptomatic and asymptomatic patients, and of culprit (CC) and non-culprit (NC) arteries in symptomatic patients. Multi-slice analysis was conducted using a 3D volume defined by ROIs drawn on 14 consecutive CT slices of 3mm thickness, covering 3cm of carotid artery. The Mann-Whitney U test was used for inter-subject comparisons (ASX vs CC; ASX vs NC) and the Wilcoxon signed-rank test was used for intra-subject comparisons (CC vs NC). A p value &lt;0.0005 was deemed statistically significant after Bonferroni correction for multiple comparisons. Non-normally distributed variables are reported as median (interquartile range).

Results

The dataset comprised 82 carotid arteries from 41 symptomatic patients (41 culprit; 41 non-culprit) and 50 carotid arteries from 25 asymptomatic patients. Single-slice analysis revealed greater homogeneity in asymptomatic carotids versus symptomatic culprit carotids (Uniformity: ASX 0.11 (0.05); CC 0.08 (0.05), p&lt;0.0005) and non-culprit carotids (NC 0.08 (0.18), p&lt;0.0005). In multi-slice analysis, culprit and non-culprit carotid arteries displayed greater heterogeneity than asymptomatic carotids (GLSZM zone entropy: CC 6.57 (0.59); NC 6.76 (0.65); ASX 6.21 (0.32), p&lt;0.0005). Multi-slice analysis of symptomatic culprit versus non-culprit carotids revealed greater heterogeneity in culprit carotids than non-culprit carotids (GLRLM run entropy CC 6.57 (0.59); NC 5.05 (0.70), p&lt;0.0001).

Conclusion

Textural analysis of carotid CTAs reveal significant differences between symptomatic and asymptomatic patients and between culprit and non-culprit carotid arteries within symptomatic patients. This approach could be used to identify patients at high risk of further stroke for aggressive medical therapy and surveillance.

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): EPVL is undertaking a PhD funded by the Cambridge School of Clinical Medicine and the Medical Research Council's Doctoral Training Partnership

Pericoronary adipose tissue density is associated with clinical disease activity in Takayasu arteritis and coronary arterial inflammation measured by 68Ga-DOTATATE PET in atherosclerosis

Background

Coronary artery disease (CAD) is an under-recognized complication of intense arterial inflammation in Takayasu arteritis (TAK). While pericoronary adipose tissue (PCAT) density is associated with arterial inflammation in CAD patients, this relationship has not previously been studied in TAK patients, nor directly compared with coronary arterial inflammation measured by 68Ga-DOTATATE positron emission tomography (PET).

Purpose

To compare PCAT density with clinical, biochemical and molecular imaging markers of inflammation in TAK and CAD patients.

Methods

PCAT density was quantified from computed tomography coronary angiography (CTCA) around each of the 17 coronary segments in patients with: (1) TAK and CAD, (2) atherosclerotic CAD, and (3) age and gender-matched healthy controls, using semi-automated software (Autoplaque). In TAK patients, PCAT density was compared to the Indian Takayasu Clinical Activity Score (ITAS) and high-sensitivity C-reactive protein (CRP). In CAD patients, PCAT density was compared to local arterial inflammation measured by coronary motion-frozen 68Ga-DOTATATE PET using image registration software (FusionQuant), and systemic (aortic) inflammation using 18F-fluorodeoxyglucose (FDG) PET. Data was acquired either during routine clinical care or prior research that established 68Ga-DOTATATE as an experimental marker of arterial inflammation that binds macrophage somatostatin receptor-2 in atherosclerotic plaques (NCT02021188).

Results

60 patients were included (TAK, n=20; CAD, n=20; healthy, n=20). Non-calcified plaque burden (TAK: 95.2%; CAD: 90.4%, p&lt;0.0001) and CRP (TAK: 25.2 ±SD 16.1 mg/L; CAD: 2.5 ±SD 1.7 mg/L, p=0.04) were greater in TAK than CAD patients.

PCAT density varied significantly among the three groups (median [IQR] TAK: −72.9 [−81.2 to -66.1] Hounsfield unit [HU]; CAD: −79.9 [−88.0 to −72.2]; healthy: −83.8 [−90.1 to −75.8] HU, p&lt;0.0001). Figure: box-plot showing the distribution of PCAT values by group, with corresponding representative multiplanar reconstructed and cross-sectional CTCA images with surrounding PCAT density displayed by color table in left anterior descending arteries.

PCAT density was significantly associated with ITAS (r=0.61, p=0.004) and CRP (r=0.43, p=0.03) in TAK patients, and coronary 68Ga-DOTATATE maximum tissue-to-blood ratio (r=0.31, p&lt;0.001) in CAD patients. PCAT density was not associated with aortic 18F-FDG uptake in CAD patients, nor subcutaneous (pre-sternal) adipose tissue density in either disease group. No significant patient-level confounders were identified using linear mixed-effects regression modelling.

Conclusion

PCAT density measured by CTCA is greater in TAK than CAD patients, and is associated with clinical and biochemical markers of disease activity in TAK, and coronary arterial inflammation measured by 68Ga-DOTATATE PET in CAD. PCAT could be a useful, easy to measure marker of coronary inflammation and disease activity in both TAK and CAD.

PCAT density is greater in TAK than CAD

Funding Acknowledgement

Type of funding source: Foundation. Main funding source(s): Wellcome Trust

Provision and Utilization of Team- and Community-Based Operative Care for Patients With Cleft Lip/Palate in North Carolina

OBJECTIVE

To characterize operative care for cleft lip and/or palate (CL/P) based on location (ie, from American Cleft Palate Craniofacial Association [ACPA]-approved multidisciplinary teams or from community providers).

DESIGN

Cross-sectional analysis of Healthcare Cost and Utilization Project State Inpatient Database and State Ambulatory Surgery & Services Database databases for North Carolina from 2012 to 2015.

SETTING/PATIENTS AND MAIN OUTCOME MEASURES

Clinical encounters for children with CL/P undergoing operative procedures were identified, classified by location as "Team" versus "Community," and characterized by demographic, geographic, clinical, and procedural factors. A secondary evaluation reviewed concordance of team and community practices with an ACPA guideline related to coordination of care.

RESULTS

Three teams and 39 community providers performed a total of 3010 cleft-related procedures across 2070 encounters. Teams performed 69.7% of total volume and performed the majority of cleft procedures, including cleft lip repair, palate repair, alveolar bone grafting, and correction of velopharyngeal insufficiency. Community locations principally offered myringotomy and rhinoplasty. Team care was associated with higher guideline concordance.

CONCLUSIONS

American Cleft Palate Craniofacial Association -approved team-based care accounts for the majority of cleft-related care in North Carolina; however, a substantial volume of cleft-related procedures was provided by community providers, with 3 providers accounting for the vast majority of community cases.

Assessing the Influence of Attending Surgeon Continuity on Free Flap Outcomes Following Unplanned Returns to the Operating Room

BACKGROUND

 Unplanned returns to the operating room (OR) may be necessary at times to salvage a compromised free flap. The aim of this study was to assess the influence of attending surgeon continuity on free flap outcomes following a return to the OR.

METHODS

 We retrospectively reviewed patients who underwent free flap reconstruction and experienced an unplanned return to the OR within 30 days from 2002 to 2017. Logistic regression modeling was used to determine factors that predict unplanned returns to the OR.

RESULTS

 Of the 1,177 patients were identified, 267 (22.5%) had an unplanned return to the OR. Of these, 69 (5.9%) patients experienced total flap loss. Overall, 216 take-back procedures were performed by the primary surgeons (80.2%), while 50 were performed by covering surgeons (18.8%). Flap loss occurred more frequently during a weekend procedure (p = 0.013). Additionally, when the take-back procedure was performed within 5 days of the original surgery by the primary as opposed to a covering surgeon, patients experienced lower estimated blood loss (75 vs. 150 cc, p = 0.04). Overall, there was a significantly lower incidence of flap loss when the take-back procedure was performed by the primary, as opposed to the covering, surgeon (20 vs. 47%, p = 0.0001).

CONCLUSION

 Higher rates of flap loss occur when a covering surgeon performs a take-back procedure in comparison to the primary surgeon. It is important to ensure the availability of the primary surgeon in the first few postoperative days following free flap reconstruction. When transfer of care is necessary, photographic or video documentation of the microvascular anastomosis may be helpful in addition to a verbal sign out.

Assessing the Utility of Post-Mastectomy Imaging after Breast Reconstruction

BACKGROUND

Few guidelines exist regarding surveillance and diagnostic imaging after breast reconstruction. This study investigated the influence of breast reconstruction on the frequency of post-mastectomy imaging, the relative utility of imaging, and its effect on overall and locoregional recurrence-free survival.

STUDY DESIGN

A retrospective review identified breast cancer patients (n = 1,216) who underwent mastectomy with or without reconstruction. Logistic regression identified surgical and oncologic predictors of post-reconstruction imaging. Kaplan-Meier method determined the impact of post-reconstruction imaging on overall and locoregional recurrence-free survival.

RESULTS

Overall, 662 (54.4%) patients underwent mastectomy only and 554 (45.6%) underwent breast reconstruction. Patients undergoing reconstruction were more likely to receive imaging compared with patients undergoing mastectomy only (n = 205, 37.0% vs n = 168, 25.4%; p < 0.0001); however, this difference was not statistically significant after adjusting for age and follow-up time (p = 0.16). Most radiographic studies were Breast Imaging Reporting and Data System (BI-RADS) 1 (n = 58, 30%) or 2 (n = 95, 49%) and were ordered by nonsurgical providers (n = 128, 63%). Post-reconstruction imaging did not influence overall or locoregional recurrence-free survival. The 5-year survival probabilities for breast reconstruction patients who underwent imaging for a palpable mass, surveillance, or who did not undergo imaging were 100%, 95% (95% CI 89% to 100%), and 96% (95% CI 94% to 99%), respectively. Post-reconstruction imaging was not a significant predictor of overall survival (hazard ratio [HR] 0.95; 95% CI 0.61 to 1.46; p = 0.30).

CONCLUSIONS

The limited utility of routine post-reconstruction imaging should be reinforced when evaluating breast reconstruction patients. Multidisciplinary collaboration should be emphasized when attempting to distinguish benign postoperative findings from a malignant process to reduce unnecessary imaging and biopsy after breast reconstruction.

Pro-inflammatory high-density lipoproteins and atherosclerosis are induced in lupus-prone mice by a high-fat diet and leptin

Atherosclerosis is accelerated in people with systemic lupus erythematosus, and the presence of dysfunctional, pro-inflammatory high-density lipoproteins is a marker of increased risk. We developed a mouse model of multigenic lupus exposed to environmental factors known to accelerate atherosclerosis in humans - high-fat diet with or without injections of the adipokine leptin. BWF1 mice were the lupus-prone model; BALB/c were non-autoimmune controls. High-fat diet increased total serum cholesterol in both strains. In BALB/c mice, non-high-density lipoprotein cholesterol levels increased; they did not develop atherosclerosis. In contrast, BWF1 mice on high-fat diets developed increased quantities of high-density lipoproteins as well as elevated high-density lipoprotein scores, indicating pro-inflammatory high-density lipoproteins; they also developed atherosclerosis. In the lupus-prone strain, addition of leptin increased pro-inflammatory high-density lipoprotein scores and atherosclerosis, and accelerated proteinuria. These data suggest that environmental factors associated with obesity and metabolic syndrome can accelerate atherosclerosis and disease in a lupus-prone background.

Quantification of myocardial perfusion and determination of coronary stenosis severity during hyperemia using real-time myocardial contrast echocardiography

Although regional myocardial perfusion can be currently quantified with myocardial contrast echocardiography (MCE) by using intermittent harmonic imaging (IHI), the method is tedious and time-consuming in the clinical setting. We hypothesized that regional myocardial perfusion can be quantified and the severity of coronary stenosis determined during hyperemia with MCE using real-time imaging (RTI) where microbubbles are not destroyed. Six open-chest dogs were studied during maximal hyperemia induced by adenosine in the absence or presence of coronary stenoses varying from mild to severe. Myocardial blood flow (MBF) was measured at each stage by using radiolabeled microspheres. MCE was performed using both IHI and RTI. Data for the latter were acquired in both end-systole and end-diastole. No differences were found between myocardial flow velocity (MFV) derived from IHI and RTI when end-systolic frames were used for the latter. MFV was consistently higher for RTI (P <.01) when end-diastolic frames were used. A linear relation was noted between MFV and radiolabeled microsphere-derived MBF ratios from the stenosed and the normal beds when end-systolic frames were used for RTI (r = 0.78, P <.001), whereas no relation was found when end-diastolic frames were used (r = 0.08, P =.78). The scatter for assessing MBF (A.beta) was minimal for IHI and RTI (9%-10%) with end-systolic frames, whereas that for RTI with end-diastolic frames was large (30%). Furthermore the correlation with radiolabeled microsphere-derived MBF was significantly (P <.01) weaker with RTI when end-diastolic frames were used (r = 0.53) than when end-systolic frames (r = 0.94) or IHI was used (r = 0.99). Data acquisition for IHI was 10 minutes, whereas it was 8 seconds for RTI. Thus, RTI can be used to quantify regional myocardial perfusion and stenosis severity during MCE. Only end-systolic frames, however, provide accurate data. RTI offers a rapid and easy means of assessing regional myocardial perfusion with MCE.

Mechanism of myocardial dysfunction in the presence of chronic coronary stenosis and normal resting myocardial blood flow: clinical implications

In chronic coronary artery disease, resting myocardial dysfunction can exist despite normal resting transmural myocardial blood flow (MBF). We hypothesized that this phenomenon occurs because of diminished endocardial MBF reserve. MBF (measured with radiolabeled microspheres) and wall thickening (WT) (measured with echocardiography) were assessed in 7 dogs after the development of severe left ventricular dysfunction caused by placement of ameroid constrictors on the left anterior descending (LAD) and left circumflex arteries and 3 weeks after selective bypass surgery to the LAD. Before surgery, the mean transmural MBF at rest and at peak dobutamine dose in the LAD bed were 1.1 +/- 0.5 and 3.0 +/- 1.5 mL/min per gram, respectively, and were not significantly changed after LAD bypass. The resting endocardial-to-epicardial MBF ratio (EER) was also normal before bypass (1.5 +/- 0.6) and remained unchanged after surgery. The prebypass EER at peak dobutamine dose, however, was markedly diminished in the LAD bed (0.7 +/- 0.3) and improved significantly (1.3 +/- 0.8, P <.01) after surgery. Resting WT in the LAD bed also improved to normal levels (36% +/- 4% versus 13% +/- 6%, P =.0001) and no longer demonstrated a biphasic response to dobutamine. In comparison, the nonbypassed left circumflex bed continued to show reduced resting WT (12% +/- 6%), a biphasic response to dobutamine, and abnormal EER during rest and dobutamine (0.7 +/- 0.3). We conclude that persistent myocardial dysfunction in the presence of normal resting transmural MBF can occur as a result of diminished endocardial MBF reserve, with transmural MBF reserve remaining normal.

Mechanism of reversible (99m)Tc-sestamibi perfusion defects during pharmacologically induced vasodilatation

Reversible perfusion defects on (99m)Tc-sestamibi imaging during hyperemia are thought to occur due to myocardial blood flow (MBF) "mismatch" between regions with and without stenosis. We have recently shown that myocardial blood volume (MBV) distal to a stenosis decreases during hyperemia, resulting in a reversible perfusion defect on myocardial contrast echocardiography (MCE). In this study, we hypothesized that a reversible perfusion defect on (99m)Tc-sestamibi imaging during hyperemia results from the same mechanism. We tested our hypothesis under the following conditions: 1) increases in MBF in the absence of changes in MBV by using direct intracoronary infusion of adenosine (group I, n = 10 dogs); 2) decrease in MBV despite an increase in MBF by left main infusion of adenosine proximal to a noncritical coronary stenosis placed on either coronary artery (group II, n = 13 dogs); and 3) reduction in both resting MBF and MBV by placement of a severe stenosis (group III, n = 7 dogs). In group I dogs, no difference in MBV or (99m)Tc-sestamibi uptake was found between the two coronary beds despite an up to fourfold increase in MBF in one bed with adenosine. In group II dogs, MBV distal to the stenosis decreased during hyperemia despite a twofold increase in mean MBF. A good correlation was found between (99m)Tc-sestamibi uptake and MBV ratios from the stenosed versus normal bed (r = 0.91, P < 0.001). In group III dogs, both MBF and MBV were decreased in the stenosed bed at rest with a good correlation noted between (99m)Tc-sestamibi uptake and MBV ratios from the stenosed versus normal bed (r = 0.92, P = 0.004). We conclude that reversible defects on (99m)Tc-sestamibi during vasodilator stress imaging are related to decreases in MBV distal to a stenosis and not to "flow mismatch" between beds. The decrease in MBV results in reduced (99m)Tc-sestamibi uptake during hyperemia.

Quantification of renal blood flow with contrast-enhanced ultrasound

OBJECTIVES

The goal of this study was to determine the ability of contrast-enhanced ultrasound (CEU) to quantify renal tissue perfusion.

BACKGROUND

The kinetics of tracers used to assess renal perfusion are often complicated by countercurrent exchange, tubular transport or glomerular filtration. We hypothesized that, because gas-filled microbubbles are pure intravascular tracers with a rheology similar to that of red blood cells, CEU could be used to quantify renal tissue perfusion.

METHODS

During a continuous venous infusion of microbubbles (SonoVue), regional renal perfusion was quantified in nine dogs using CEU by destroying microbubbles and measuring their tissue replenishment with intermittent harmonic imaging. Both renal blood volume fraction and microbubble velocity were derived from pulsing-interval versus video-intensity plots. The product of the two was used to calculate renal nutrient blood flow. Renal arterial blood flow was independently measured with ultrasonic flow probes placed directly on the renal artery and was increased using dopamine and decreased by placement of a renal artery stenosis.

RESULTS

An excellent correlation was found between cortical nutrient blood flow using microbubbles and ultrasonic flow probe-derived renal blood flow (r = 0.82, p < 0.001) over a wide range (2.5 fold) of flows.

CONCLUSIONS

Ultrasound examination during microbubble infusion can be used to quantify total organ as well as regional nutrient blood flow to the kidney.

The relation between human fetal growth and fetal blood levels of insulin-like growth factors I and II, their binding proteins, and receptors

OBJECTIVE

To determine the relation between normal human fetal growth and the levels of insulin-like growth factors (IGF-I, IGF-II), their receptors, and IGF binding protein-3 (IGFBP-3) in both the maternal and fetal compartments.

METHODS

Serum samples were obtained from normal pregnant women (n = 52) and their fetuses (n = 32) via funipuncture at 21-34 weeks' gestation (mean 29 +/- 4.3) and from term neonates (n = 20) between 38-41 weeks (mean 39 +/- 0.9). Neonates were divided into two groups: the "large" group, whose weights were above the mean for gestational age, and the "small" group, whose weights were below the mean. Aliquots of amniotic fluid (AF) and serum samples were analyzed for levels of IGF-I, IGF-II, and IGFBP-3. Type 1 IGF receptors were assayed from placental extracts of first-trimester elective abortions and from term deliveries.

RESULTS

Fetal IGF-I serum levels remained stable throughout most of pregnancy until 34 weeks' gestation (56 +/- 30 ng/mL). Thereafter, IGF-I increased significantly until term (79 +/- 8 ng/mL) (P < .05). Fetal IGF-II levels were relatively unchanged from 23 weeks to term except for a significant increase at 34 weeks. Fetal serum levels of IGFBP-3 averaged 0.8 +/- 0.05 microgram/mL up to 30 weeks' gestation and then increased slightly toward term, at 0.96 +/- 0.05 micrograms/mL. At term, the levels of IGF-I and IGF-II in the AF were not different from the levels in the neonatal serum, but were lower (P < .005) than those in maternal blood. All placental tissue obtained from first-trimester terminations of pregnancy assayed positive for IGF type 1 receptors. There was a direct correlation between neonatal weight and the levels of IGF-I (P < .02), but not with the levels of IGF-II. There were no significant correlations between newborn weights and IGFBP-3, or maternal serum levels of IGF-I and IGF-II. Amniotic fluid IGF-I and IGF-II levels were almost similar to fetal serum levels.

CONCLUSION

These data demonstrate the presence of type 1 receptors and the bioavailability of IGF-I, IGF-II, and IGFBP-3 throughout pregnancy. Insulin-like growth factor-I is shown to be adjunctively and directly associated with fetal size in normal pregnancies. The precise role that IGFs play in deviant fetal growth or whether IGFs can be used to treat reduced fetal growth remains unknown and awaits further investigation.

Circulatory and metabolic effects of beta-adrenergic blockade in the hyperinsulinemic ovine fetus

Offspring of women with poorly controlled diabetes exhibit hypoxemia, elevated catecholamine concentration at birth, and an increased incidence of fetal death. Experimental fetal hyperinsulinemia results in increased catecholamine concentration and hemodynamic changes including increased combined ventricular output and vasodilation of select fetal organs. We hypothesized that insulin-induced catecholamine-mediated beta-adrenergic stimulation supports some of these hemodynamic changes in the hyperinsulinemic ovine fetus. To study this, 24 chronically instrumented fetal sheep receiving insulin for 24 h were exposed to beta-(propranolol),beta 1-(metoprolol), and beta 2-(ICI 118,551) adrenergic blockade. Insulin infusion resulted in hyperinsulinemic-hypoglycemia, a surge in epinephrine and norepinephrine concentration, and increases in the combined ventricular output and regional blood flow to the heart, adrenal glands, kidney, gastrointestinal tract, liver, fat, muscle, carcass, and placenta. In the hyperinsulinemic state, beta-adrenergic blockade was associated with significant reductions in the combined ventricular output and blood flow to fat, carcass, lungs, and the placenta; beta 1-blockade was associated with reductions in the combined ventricular output and blood flow to the lungs; and beta 2-adrenergic blockade was associated with reductions in blood flow to muscle and lungs. Because beta-adrenergic blockade was associated with reductions in placental blood flow during hyperinsulinemia, oxygen and glucose metabolism were also compromised. We conclude that in the hyperinsulinemic-hypoglycemic normoxemic ovine fetus, insulin-induced catecholamine-mediated hemodynamic changes are modulated in part by beta-adrenergic receptor stimulation.