Two-stage laparoscopic transversus abdominis plane block as an equivalent alternative to thoracic epidural anaesthesia in bowel resection-an explorative cohort study.

PURPOSE: We evaluated the effect of the two-stage laparoscopic transversus abdominis plane block (TS-L-TAPB) in comparison to thoracic epidural anaesthesia (TEA) and a one-stage L-TAPB (OS-L-TAPB) in patients who underwent elective laparoscopic bowel resection. METHODS: We compared a TS-L-TAPB (266 mg bupivacaine), which was performed bilaterally at the beginning and end of surgery, with two retrospective cohorts. These were patients who had undergone a TEA (ropivacaine/sufentanil) or an OS-L-TAPB (200 mg ropivacaine) at the beginning of surgery. Oral and i.v. opiate requirements were documented over the first 3 postoperative days (POD). RESULTS: Patients were divided into three groups TEA (n = 23), OS-L-TAPB (n = 75), and TS-L-TAPB (n = 49). By the evening of the third POD, patients with a TEA had a higher cumulative opiate requirement with a median of 45.625 mg [0; 202.5] than patients in the OS-L-TAPB group at 10 mg [0; 245.625] and the TS-L-TAPB group at 5.625 mg [0; 215.625] (p = 0.1438). One hour after arrival in the recovery room, significantly more patients in the TEA group (100%) did not need oral and i.v. opioids than in the TS-L-TAPB (78%) and OS-L-TAPB groups (68%) (p = 0.0067).This was without clinical relevance however as the median in all groups was 0 mg. On the third POD, patients in the TEA group had a significantly higher median oral and i.v. opioid dose at 40 mg [0; 80] than the TS-L-TAPB and OS-L-TAPB groups, both at 0 mg [0; 80] (p = 0.0009). CONCLUSION: The TS-L-TAP showed statistically significant and clinically meaningful benefits over TEA and OS-L-TAP in reducing postoperative opiate requirements.

Use of licap and ltap flaps for breast reconstruction.

Breast conserving surgery has been reserved for patients with favorable proportion between tumor dimensions and breast size. Introduction of local flaps from the lateral thoracic region has widened the indications for breast conserving surgery, by allowing surgeons to perform wider excisions, thus yet be able to ensure tumor-free surgical margins and a good aesthetic result. We have used lateral intercostal perforator flaps and flaps harvested on the lateral thoracic artery and lateral thoracic artery axial flap in patients with small breasts and an unfavorable tumor to breast size proportion. From May 2015 to October 2016, 19 patients with breast tumors have been treated with BCS and immediate volume replacement reconstruction by pedicle perforator flaps from the lateral thoracic region. In 15 patients lateral intercostal artery perforator flaps or lateral thoracic artery perforator flaps were used after quadrantectomy or wide local excision, in 3 patients as volume replacement after mastectomy and in 1 patient after mastectomy following previous augmentation mammoplasty. In all patients, good breast symmetry was achieved, with no major complications. Fibrosis of the flap and residual breast parenchyma, with volume reduction were noticed after postoperative radiotherapy in thin patients or flaps with little subcutaneous fat. Perforator flaps from the lateral thoracic region should become the gold standard for reconstructions after breast conserving surgery involving less than 20% of the breast volume or after mastectomy in patients with small breasts. The operating procedure is safe, quick and allows sparing of the latissimus dorsi muscle and thus minimal donor site morbidity, as well as an excellent aesthetic result.

Adipose perforator flaps without skin donor site: "in between" single scar approach for reconstruction of small peripheral breast defects after lumpectomy.

In breast conserving surgery, the reconstruction of defects in small breasts where volume displacement techniques are not feasible can be challenging. In contrast, patients with bigger breasts may not wish to undergo major breast remodeling surgery or breast symmetrization procedures. In such cases, volume replacement techniques can be beneficial, but these leave additional scars and are time consuming. The authors propose an "in between" single scar approach to perform both lumpectomy and reconstruction of small peripheral breast tumors. This approach reduces morbidity and operating time compared with standard volume replacement techniques. The tumors are resected from below, guided by wire, using an incision in the lateral breast crease or inframammary fold, depending on their location. The same incision is used to raise an adipose or adipofascial flap based on perimammary perforators, lateral thoracic artery perforator flap (LTAP), lateral intercostal artery perforator flap (LICAP), or anterior intercostal artery perforator flaps (AICAP) flaps, without skin donor site. Between March and November 2022, eight patients underwent this procedure. In four cases LICAP flap was used; in three-AICAP flap was chosen; and in one-LTAP perforator flap was used. Clear surgical margins were achieved in all cases. The average follow-up time was 9.9 months, during which no local recurrences were detected. All flaps survived. Two patients experienced seromas at the donor site, and an organized hematoma was also reported. This approach represents a viable alternative to volume displacement techniques or no reconstruction for small peripheral lumpectomy defects.

Chest wall perforator flaps for partial breast reconstruction after conservative surgery: Prospective analysis of safety and reliability.

INTRODUCTION: Breast-conserving surgery associated with adjuvant radiotherapy is the state of the art in the surgical treatment of breast cancer. Oncoplastic surgery through dermo-adipose flaps based in perforating arteries (muscle sparing flaps) for partial reconstruction is increasingly used as a good option for avoiding musculocutaneous flaps. In this study we evaluate the outcomes of the use of chest wall perforator flaps in the replacement of partial breast volume. METHODS: A prospective cohort study of female patients that underwent a conservative oncoplastic surgery procedure with partial breast reconstruction using a dermo-adipose flap of perforating arteries of the chest wall was conducted between November 2020 and March 2022 at our centre. Primary outcomes were surgical morbidity, positive margins and reoperation rates. Characteristics associated with the occurrence of complications were further identified. RESULTS: Forty-five patients underwent the procedure of interest during the study period. The mean age was 55 years. The median larger dimension of the tumor was 23 mm. Lateral intercostal artery perforator (LICAP), lateral thoracic artery perforator (LTAP), a combined flap and Anterior Intercostal Artery Perforator/Medial Intercostal Artery Perforator (AICAP)/(MICAP) were performed in 22, 16, 2 and 5 patients, respectively. The mean operative time was 126 min. A total of 9 (20.0%) patients required a reoperation after definitive diagnosis, 4 due to positive margins and 5 due to immediate/early surgical morbidity. CONCLUSIONS: Local perforator flaps in oncoplastic breast-conserving surgery are a good option for immediate reconstruction after conservative surgery, showing low morbidity and favourable outcomes.

'PartBreCon' study. A UK multicentre retrospective cohort study to assess outcomes following PARTial BREast reCONstruction with chest wall perforator flaps.

BACKGROUND: Partial breast reconstruction with a pedicled chest wall perforator flap (CWPF) enables breast conservation in a higher tumour: breast volume ratio scenario. Since there is limited evidence, this retrospective cohort study aimed to ascertain immediate (30-days) and medium-term (follow-up duration) surgical outcomes. METHODS: STROBE-compliant protocol ascertained CWPF outcomes between March 2011-March 2021. UK centres known to perform CWPF were invited to participate if they performed at least 10 cases. Data were retrospectively collected, including patient demographics, tumour and treatment characteristics, and surgical and oncological outcomes. Statistical analysis (R™) included multivariable logistic regression and sensitivity analysis. RESULTS: Across 15 centres, 507 patients with median age (54 years, IQR; 48-62), body mass index (25.4 kg/m2, IQR; 22.5-29), tumour size (26 mm, IQR; 18-35), and specimen weight (62 g, IQR; 40-92) had following flap types: LiCAP (54.1%, n = 273), MiCAP/AiCAP (19.6%, n = 99), LiCAP + LTAP (19.8%, n = 100) and TDAP (2.2%, n = 11). 30-days complication rates were in 12%: haematoma (4.3%, n = 22), wound infection (4.3%, n = 22), delayed wound healing (2.8%, n = 14) and flap loss (0.6%, n = 3; 1 full) leading to readmissions (2.6%, n = 13) and re-operations (2.6%, n = 13). Positive margins (n = 88, 17.7%) led to 15.9% (n = 79) re-excisions, including 7.5% (n = 37) at the planned 2nd of 2-stage surgery and 1.8% (n = 9) mastectomy. At median 23 months (IQR; 11-39) follow-up, there were 1.2% (n = 6) symmetrisations; recurrences: local (1%), regional/nodal (0.6%) and distant (3.2%). CONCLUSIONS: This large multicentre cohort study demonstrates acceptable complication and margin re-excision rates. CWPF extends the range of breast conservation techniques. Further studies are required for long-term oncological outcomes.

Exploration of chest wall perforator vascular anatomy on standard breast MRI: A potential aid to chest wall perforator flap planning.

Local chest wall perforator flaps (CWPFs) are a volume replacement technique permitting breast-conserving surgery in patients who otherwise may require a mastectomy. These flaps are based on one or more perforating arteries arising from the lateral chest wall that travel through the soft tissue and into the sub-dermal plexus to perfuse the flap. Examples include the lateral intercostal and lateral thoracic artery perforators (LICAP and LTAP, respectively). Cross-sectional imaging of perforating vessels is not routinely performed, and vessels are mapped pre- and peri-operatively using a hand-held acoustic doppler device. As many breast cancer patients undergo pre-operative MRI scanning for oncological purposes, we investigated the role of MRI in mapping the vascular anatomy to aid with the surgical planning of CWPFs. We collated data retrospectively on a cohort of breast cancer patients who underwent breast MRI as part of routine pre-operative imaging. Axial 3D high-resolution dynamic contrast-enhanced MRI sequences with multiplanar reconstructions were analysed by a consultant radiologist. The presence and calibre of lateral chest wall perforator vessels were assessed. Fifty patients were suitable for inclusion. A consistent pattern of lateral chest wall vasculature was observed. Forty-eight patients (96%) demonstrated a bilateral lateral thoracic artery (LTA) descending inferiorly along the chest wall with two-thirds of these communicating with perforating intercostal vessels. True independent LICAP vessels were identified in six patients. From our observations, lateral CWPFs are dependent on an intricate intercommunication between intercostal vessels and the LTA which in turn supply perforators to the lateral chest wall donor site.

Lateral chest wall perforator flaps in partial breast reconstruction.

BACKGROUND: Breast conserving surgery (BCS) has been a standard procedure for the treatment of breast cancer instead of mastectomy whenever possible. Lateral chest wall perforator flaps are one of the volume replacement techniques that participate in increasing the rate of BCS especially in small- to moderate-sized breasts with good cosmetic outcome. In this study, we tried to evaluate the outcome of those flaps as an oncoplastic procedure instead of the conventional flaps. METHODS: This study included 26 patients who underwent partial mastectomy with immediate reconstruction using lateral chest wall perforator flaps in the period from October 2019 to November 2020. The operative time, techniques, and complications were recorded. The cosmetic outcome was assessed 3 months post-radiation therapy through a questionnaire and photographic assessment. RESULTS: Lateral intercostal artery perforator (LICAP), lateral thoracic artery perforator (LTAP) and combined flaps were performed in 24, 1, and 1 patients, respectively. The mean operative time was 129.6 ± 13.2 min. The flap length ranged from 10 to 20 cm and its width from 5 to 9 cm. Overall patients' satisfaction was observed to be 88.5% as either excellent or good and the photographic assessment was 96.2% as either excellent or good. CONCLUSIONS: Lateral chest wall perforator flaps are reliable and safe option for partial breast reconstruction with an acceptable aesthetic outcome. In the era of oncoplastic breast surgery, they deserve to gain attention especially with the advantages of some modifications added to the classic technique.

Laparoscopically guided transversus abdominis plane block versus local wound analgesia in laparoscopic surgery for peritoneal endometriosis: study protocol for a prospective randomized controlled double-blinded LTAP-trial.

BACKGROUND: Ultrasound-guided transversus abdominis plane block (TAP) performed by anesthesiologist has been shown to be an effective and safe analgesia method in abdominal surgery, reducing postoperative opioid consumption. Recently, there has been growing interest to insert TAP under laparoscopic vision (LTAP) by surgeon. LTAP has been used in laparoscopic gastrointestinal surgery, but studies on LTAP in gynecologic laparoscopic surgery are sparse and inconsistent. The purpose of this study is to compare the efficacy of LTAP and local wound analgesia in laparoscopic surgery due to suspected or diagnosed superficial peritoneal endometriosis. METHODS: The LTAP-trial is a prospective randomized controlled double-blinded study comparing the efficacy and safety of LTAP with local wound analgesia in laparoscopic endometriosis surgery. Patients are randomized to receive LTAP with levobupivacaine and wound infiltration with placebo or wound infiltration with levobupivacaine and LTAP with placebo. The primary outcome is postoperative opioid consumption measured by patient-controlled analgesia (PCA) pump. Secondly, subjective postoperative pain up to 24 h postoperatively will be measured by Numeric Rating Scale (NRS). Additional outcome measures are factors related to recovery and length of stay in the hospital as well as a 6-month follow-up survey regarding pain (NRS) and endometriosis-related wellbeing (endometriosis-related health profile, EHP-30) after surgery. A total of 46 patients will be randomized in a proportion of 1:1. DISCUSSION: Patients with peritoneal endometriosis are often prone to severe postoperative pain that may prohibit their enhanced recovery after laparoscopy. Thus, there is a need for effective postoperative pain management with minimal side-effects. This study focusing on laparoscopically inserted transversus abdominis plane block may provide new insight in dealing with postoperative pain after laparoscopic endometriosis surgery as well as after other gynecologic surgery. TRIAL REGISTRATION: The LTAP-trial -protocol has been prospectively registered to ClinicalTrials.gov , ID: NCT04735770 . Registered on February 2021.

A single centre experience of local perforator flaps in oncoplastic breast surgery; a cross-sectional study.

Background & objectives: Various oncoplastic techniques have emerged over the years to preserve breast cosmesis and symmetry without compromising the principles of tumor excision. One of the newer techniques for breast volume replacement to achieve symmetry and cosmesis is the use of fasciocutaneous pedicled chest wall perforator flaps or local perforator flaps (LPF). The objectives of this study were to document the details of the surgical procedure as well as patient-reported satisfaction and well-being following the procedure using a validated BREAST-Q tool among Pakistani women. Materials & methods: This cross-sectional study was conducted from March 2019 to February 2021 enrolling 25 female patients who underwent breast conservative surgery using LPF for breast tumors at The Aga Khan University Hospital, Karachi. Data related to the procedure was collected on a pre-designed proforma. Cosmetic outcomes and patient satisfaction were evaluated using 2 scales from BREAST-Q BCT domain version 2.0. The questionnaire was self-administered by the patients during their routine follow-up in the clinic. Data was analyzed using the Statistical Package for Social Sciences (SPSS) version 23. Mean (SD)/median (IQR) were computed for quantitative variables and frequency and percentages were calculated for qualitative variables. 2 sample t-test was applied. P-value ≤0.05 was considered significant. Results: 25 patients underwent LPF with a mean age of 47 ± 13.1 years. 8 LICAP, 7 AICAP, and 10 LTAP flaps were performed. Two postoperative complications of wound site erythema were encountered. 23 women were eligible for the BREAST-Q survey. Median (IQR) postoperative satisfaction with breasts and physical well-being chest (equivalent Rasch transformed score) was 100 (41) and 76 [18] respectively. We found high satisfaction with breasts and comparable physical well-being among Pakistani women after LPF surgeries. Conclusion: Local perforator flaps in oncoplastic breast-conserving surgery are a good option showing high satisfaction with breasts and physical well-being in Pakistani women.

Considering real-world sightline obstructions in crash and injury prevention estimates for left turn across path/opposite direction intersection active safety systems.

OBJECTIVE: Previous analyses of active safety systems in left turn across path/opposite direction (LTAP/OD) crashes have shown that sensor sightline obstructions might affect the performance of these systems. National retrospective crash databases provide little information about the proportion of cases which have sightline obstructions. One promising alternative are naturalistic driving studies (NDS). The objective of this study was to estimate the proportion of LTAP/OD crashes and near-crashes which have sightline obstructions using a large-scale NDS and update previous estimates of intersection active safety system effectiveness using this information. METHODS: LTAP/OD crash and near-crash cases were identified from the Second Strategic Highway Research Program (SHRP 2) dataset. Each case was reviewed for the presence of obstructing vehicles when the left turning vehicle began turning. This study considered 241 crash and near-crash LTAP/OD events selected from SHRP 2. SHRP 2 was an NDS which collected 80 million kilometers of driving from approximately 2,500 participants over a 2.5 year period. The sightline obstruction ratio was defined as the proportion of cases which had sightline obstructions when the turning vehicle began turning. A logistic regression model was used to determine the statistical significance of factors which affected the sightline obstruction ratio, which included event severity, traffic control device, subject vehicle crash configuration, and turning lane presence. LTAP/OD active safety system effectiveness was quantified in a prior study for cases with and without sightline obstructions separately. System effectiveness was re-computed by weighting the results according to the worst-case sightline ratio computed in this study. RESULTS: Traffic control device, subject vehicle crash type (turning or traveling through), and turning lane presence were not found to affect sightline obstruction ratio. In crash cases, the sightline obstruction ratio was 40%. In near-crash cases, the sightline obstruction ratio was 18%. Finally, the effectiveness of an intersection active safety system was evaluated using this sightline obstruction ratio. CONCLUSIONS: This study quantified the sightline obstruction ratio, an important parameter needed to evaluate intersection active safety systems. This study also establishes a baseline for evaluating the presence of sightline obstructions in a future naturalistic driving study when road infrastructure has changed.

The potential of clustering methods to define intersection test scenarios: Assessing real-life performance of AEB.

Intersection accidents are frequent and harmful. The accident types 'straight crossing path' (SCP), 'left turn across path - oncoming direction' (LTAP/OD), and 'left-turn across path - lateral direction' (LTAP/LD) represent around 95% of all intersection accidents and one-third of all police-reported car-to-car accidents in Germany. The European New Car Assessment Program (Euro NCAP) have announced that intersection scenarios will be included in their rating from 2020; however, how these scenarios are to be tested has not been defined. This study investigates whether clustering methods can be used to identify a small number of test scenarios sufficiently representative of the accident dataset to evaluate Intersection Automated Emergency Braking (AEB). Data from the German In-Depth Accident Study (GIDAS) and the GIDAS-based Pre-Crash Matrix (PCM) from 1999 to 2016, containing 784 SCP and 453 LTAP/OD accidents, were analyzed with principal component methods to identify variables that account for the relevant total variances of the sample. Three different methods for data clustering were applied to each of the accident types, two similarity-based approaches, namely Hierarchical Clustering (HC) and Partitioning Around Medoids (PAM), and the probability-based Latent Class Clustering (LCC). The optimum number of clusters was derived for HC and PAM with the silhouette method. The PAM algorithm was both initiated with random start medoid selection and medoids from HC. For LCC, the Bayesian Information Criterion (BIC) was used to determine the optimal number of clusters. Test scenarios were defined from optimal cluster medoids weighted by their real-life representation in GIDAS. The set of variables for clustering was further varied to investigate the influence of variable type and character. We quantified how accurately each cluster variation represents real-life AEB performance using pre-crash simulations with PCM data and a generic algorithm for AEB intervention. The usage of different sets of clustering variables resulted in substantially different numbers of clusters. The stability of the resulting clusters increased with prioritization of categorical over continuous variables. For each different set of cluster variables, a strong in-cluster variance of avoided versus non-avoided accidents for the specified Intersection AEB was present. The medoids did not predict the most common Intersection AEB behavior in each cluster. Despite thorough analysis using various cluster methods and variable sets, it was impossible to reduce the diversity of intersection accidents into a set of test scenarios without compromising the ability to predict real-life performance of Intersection AEB. Although this does not imply that other methods cannot succeed, it was observed that small changes in the definition of a scenario resulted in a different avoidance outcome. Therefore, we suggest using limited physical testing to validate more extensive virtual simulations to evaluate vehicle safety.

Opportunities and limitations for intersection collision intervention-A study of real world 'left turn across path' accidents.

Turning across the path of oncoming vehicle accidents are frequent and dangerous. To date not many car manufacturers have introduced Automated Emergency Braking (AEB) systems addressing this type of conflict situation, but it is foreseeable that these scenarios will be part of the Euro NCAP 2020 rating. Nine out of ten collisions are caused by the driver of the turning vehicle. An AEB system evaluating the ego and conflict vehicle driver's possibilities to avoid a pending crash by either braking or steering was specified for application in various constellations of vehicle collisions. In virtual simulation, AEB system parameters were varied, covering parameters that are relevant for driver comfort such as longitudinal and lateral acceleration (to define avoidance possibilities), expected steering maneuvers to avoid conflict, and intervention response characteristics (brake delay and ramp up) to assess the safety benefit. The reference simulation showed a potential of the AEB system in the turning vehicle to avoid approximately half of the collisions. An AEB system of the straight going vehicle was less effective. The effectiveness of the turning vehicle's AEB system increases if spatial limitations for the collision-avoidance steering maneuver are known. Such information could be provided by sensors detecting free space in or around the road environment or geographical information shared via vehicle to cloud communication. AEB interventions rarely result in collision avoidance for turning vehicles with speeds above 40km/h or for straight going vehicles with speeds above 60km/h. State of the art field-of-views of forward looking sensing systems designed for AEB rear-end interventions are capable of addressing turning across path situations.