Biodegradable, Biocompatible, and Implantable Multifunctional Sensing Platform for Cardiac Monitoring

Cardiac monitoring after heart surgeries is crucial for health maintenance and detecting postoperative complications early. However, current methods like rigid implants have limitations, as they require performing second complex surgeries for removal, increasing infection and inflammation risks, thus prompting research for improved sensing monitoring technologies. Herein, we introduce a nanosensor platform that is biodegradable, biocompatible, and integrated with multifunctions, suitable for use as implants for cardiac monitoring. The device has two electrochemical biosensors for sensing lactic acid and pH as well as a pressure sensor and a chemiresistor array for detecting volatile organic compounds. Its biocompatibility with myocytes has been tested in vitro, and its biodegradability and sensing function have been proven with ex vivo experiments using a three-dimensional (3D)-printed heart model and 3D-printed cardiac tissue patches. Moreover, an artificial intelligence-based predictive model was designed to fuse sensor data for more precise health assessment, making it a suitable candidate for clinical use. This sensing platform promises impactful applications in the realm of cardiac patient care, laying the foundation for advanced life-saving developments.

Spiral NeuroString: High-Density Soft Bioelectronic Fibers for Multimodal Sensing and Stimulation

Bioelectronic fibers hold promise for both research and clinical applications due to their compactness, ease of implantation, and ability to incorporate various functionalities such as sensing and stimulation. However, existing devices suffer from bulkiness, rigidity, limited functionality, and low density of active components. These limitations stem from the difficulty to incorporate many components on one-dimensional (1D) fiber devices due to the incompatibility of conventional microfabrication methods (e.g., photolithography) with curved, thin and long fiber structures. Herein, we introduce a fabrication approach, ‶spiral transformation″, to convert two-dimensional (2D) films containing microfabricated devices into 1D soft fibers. This approach allows for the creation of high density multimodal soft bioelectronic fibers, termed Spiral NeuroString (S-NeuroString), while enabling precise control over the longitudinal, angular, and radial positioning and distribution of the functional components. We show the utility of S-NeuroString for motility mapping, serotonin sensing, and tissue stimulation within the dynamic and soft gastrointestinal (GI) system, as well as for single-unit recordings in the brain. The described bioelectronic fibers hold great promises for next-generation multifunctional implantable electronics.

Autonomous alignment and healing in multilayer soft electronics using immiscible dynamic polymers

Self-healing soft electronic and robotic devices can, like human skin, recover autonomously from damage. While current devices use a single type of dynamic polymer for all functional layers to ensure strong interlayer adhesion, this approach requires manual layer alignment. In this study, we used two dynamic polymers, which have immiscible backbones but identical dynamic bonds, to maintain interlayer adhesion while enabling autonomous realignment during healing. These dynamic polymers exhibit a weakly interpenetrating and adhesive interface, whose width is tunable. When multilayered polymer films are misaligned after damage, these structures autonomously realign during healing to minimize interfacial free energy. We fabricated devices with conductive, dielectric, and magnetic particles that functionally heal after damage, enabling thin-film pressure sensors, magnetically assembled soft robots, and underwater circuit assembly.

The effect of non-oncology drugs on clinical and genomic risk in early luminal breast cancer

BACKGROUND

An effect of non-oncology medications on cancer outcome has been proposed. In this study, we aimed to systematically examine the impact of commonly prescribed non-oncology drugs on clinical risk and on the genomic risk [based on the Oncotype DX recurrence score (RS)] in early breast cancer (BC).

EXPERIMENTAL DESIGN

We collected data on clinical risk (stage and grade), genomic risk (Oncotype DX RS), and on non-oncology medications administered to 1423 patients with estrogen receptor-positive human epidermal growth factor receptor 2-negative BC during the month of their surgery. The influence of various medications on clinical and genomic risks was evaluated by statistical analysis.

RESULTS

Out of the multiple drugs we examined, levothyroxine was significantly associated with a high Oncotype DX RS (mean 24.78; P < 0.0001) and metformin with a low Oncotype DX RS (mean 14.87; P < 0.01) compared with patients not receiving other non-oncology drugs (mean 18.7). By contrast, there were no differences in the clinical risk between patients receiving metformin, levothyroxine, or no other non-oncology drugs. Notably, there was no association between the consumption of levothyroxine and metformin and proliferation marker (Ki67) levels, but both drugs were significantly associated with progesterone-related features, suggesting that they influence genomic risk through estrogen-dependent signaling.

CONCLUSIONS

The results of this study indicate a significant impact of metformin and levothyroxine on clinical decisions in luminal BC, with potential impact on the clinical course of these patients.

Sensors for Volatile Organic Compounds

This paper provides an overview of recent developments in the field of volatile organic compound (VOC) sensors, which are finding uses in healthcare, safety, environmental monitoring, food and agriculture, oil industry, and other fields. It starts by briefly explaining the basics of VOC sensing and reviewing the currently available and quickly progressing VOC sensing approaches. It then discusses the main trends in materials' design with special attention to nanostructuring and nanohybridization. Emerging sensing materials and strategies are highlighted and their involvement in the different types of sensing technologies is discussed, including optical, electrical, and gravimetric sensors. The review also provides detailed discussions about the main limitations of the field and offers potential solutions. The status of the field and suggestions of promising directions for future development are summarized.

Mild radiographic osteoarthritis is associated with increased pain and dissatisfaction following total knee arthroplasty when compared with severe osteoarthritis: a systematic review and meta-analysis

PURPOSE

The association between severity of radiographic osteoarthritis with patient pain, function, and satisfaction following total knee arthroplasty has been disputed. The discrepancies in current literature prompt us to further examine this association in a systematic review and meta-analysis.

METHODS

The OVID-Medline, Embase, and Web of Science databases were searched from their inception up to Mar 2020. The main independent variable was osteoarthritis severity as defined by preoperative radiographs. The outcomes measured were pain, function and satisfaction following total knee arthroplasty. A minimum of three studies assessing the same patient-reported outcome measures were included in the meta-analysis, as well as those separating patients by chronic pain or dissatisfaction.

RESULTS

29 studies were included in this study. Significant heterogeneity was seen between radiographic evaluation and reported outcomes. Patients with only mild radiographic osteoarthritis were more likely to suffer from chronic pain (odds ratio = 2.45, 95% CI = 1.80-3.34, p < 0.001) and dissatisfaction (odds ratio = 2.43, 95% CI = 1.79-3.31, p < 0.001) compared to patients with severe osteoarthritis. A significant association was found between mild radiographic severity and lower total Western Ontario and McMaster Universities Osteoarthritis scores (95% CI = - 0.37-0.06, p = 0.006) as well as Knee Society Scores (CI: - 0.54-0.16, p < 0.001).

CONCLUSION

Patients with mild radiographic osteoarthritis are anticipated to gain less from total knee arthroplasty compared to those with severe osteoarthritis. They are also at risk for chronic pain and dissatisfaction and should be consulted about this risk prior to surgery.

LEVEL OF EVIDENCE

III.

Characteristics and Early Predictors of Intensive Care Unit Admission among COVID-19 Patients in Qatar

Purpose

This study aimed to explore the early predictors of intensive care unit (ICU) admission and in-hospital mortality among patients diagnosed with Coronavirus disease (COVID-19).

Methods & Materials

This was a case-control study of adult patients with confirmed COVID-19. Cases were defined as patients admitted to ICU during the period February 29 - May 29, 2020. For each case enrolled, one control was matched by age and gender. Univariate and multivariate logistic regression models were used to identify the predictors for ICU admission and in-hospital mortality among the COVID‐19 patients.

Results

A total of 1560 patients with confirmed COVID-19 were included. Each group included 780 patients with a predominant male gender (89.7%) and a median age of 49 years (interquartile range, IQR=18). Predictors independently associated with ICU admission included having cardiovascular disease (CVD) (adjusted odds ratio (aOR)=1.64, 95% confidence interval (CI): 1.16 - 2.32, p= 0.005), diabetes (aOR=1.52, 95% CI: 1.08 - 2.13, p= 0.016), body mass index ≥30 kg/m2 (aOR=1.46, 95% CI: 1.03-2.08, p= 0.034), lymphocytes ≤0.8 × 103/μL (aOR=2.69, 95% CI: 1.80-4.02, p<0.001), aspartate aminotransferase (AST) >120 U/L (aOR= 2.59, 95% CI: 1.53-4.36, p<0.001), ferritin >600 μg/L (aOR=1.96, 95% CI: 1.40-2.74, p<0.001), C-reactive protein (CRP) >100 mg/L (aOR=4.09, 95% CI: 2.81-5.96, p<0.001), and dyspnea (aOR=2.50, 95% CI: 1.77-3.54, p <0.001). Similarly, significant predictors of mortality included CVD (aOR=2.16, 95% CI: 1.32- 3.53, p=0.002), diabetes (aOR=1.77, 95% CI: 1.07-2.90, p=0.025), cancer (aOR=4.65, 95% CI: 1.50-14.42, p= 0.008), lymphocytes ≤0.8 x,103/μL (aOR=2.34, 95% CI: 1.45-3.78, p= 0.001), and AST >120 U/L (aOR= 1.89, 95% CI: 1.04-3.43, p=0.036).

Conclusion

Having CVD, diabetes, lymphopenia, and increased AST were independent predictors for both ICU admission and in-hospital mortality in patients with COVID-19. In addition, obesity, high ferritin, and CRP levels were also associated with increased risk of ICU admission, while cancer was strongly associated with in-hospital mortality. Early identification and monitoring of patients at risk is essential in planning the level of care needed to prevent delay in medical intervention.

A Wearable Microneedle-Based Extended Gate Transistor for Real-Time Detection of Sodium in Interstitial Fluids

Sodium is a prominent prognostic biomarker for assessing health status, such as dysnatremia. As of now, detection and monitoring of sodium levels in the human body is carried out by means of laborious and bulky laboratory equipmentand/or by offline analysis of various body fluids. Herein, an innovative stretchable, skin-conformal and fast-response microneedle extended-gate FET biosensor is reported for real-time detection of sodium in interstitial fluids for minimally invasive health monitoring along with high sensitivity, low limit of detection, excellent biocompatibility, and on-body mechanical stability. The integration of the reported device with a wireless-data transmitter and the Internet-of-Things cloud for real-time monitoring and long-term analysis is reported and discussed. This platform would eventually help bringing unlimited possibilities for effecient medical care and accurate clinical decision-making.

Synthesis, characterization, and humidity-responsiveness of guar gum xanthate and its nanocomposite with copper sulfide covellite

A novel conjugation of guar gum with xanthate groups via facile aqueous xanthation reaction has been reported. Density of grafted xanthate on guar gum product (GG-X) is as high as 4.4%, thus GG-X is conceivably characterized and confirmed by various spectrometric, electrochemical, thermogravimetric, and microscopic methods. Complexation of GG-X with numerous borderline and soft metal ions (e.g. Fe²⁺, Co²⁺, Ni²⁺, Cu²⁺, Pb²⁺, Pt²⁺ and Cd²⁺) yields hydrophilic gel-like materials and shows good agreement with hard and soft acid and base (HSAB) theory. This indicates tremendous potential of GG-X in metal ion extraction, removal and hydrogel cross-linking. GG-X is also employed to formulate an aqueous colloidal dispersion of copper sulfide covellite (GG-X/CuS) nanocomposites. GG-X therefore behaves as a surfactant, allowing formation of electronically conductive nanocomposites. XRD indicates apparent beneficial effects of GG-X in the synthesis of CuS with a crystallite size of 15.6 nm. This novel nanocomposite is a promising material for humidity sensing, showing reversible linear responses to relative humidity changes within 10 to 80% range. The interaction between GG-X and water might cause changes in electrical permittivity of GG-X/CuS nanocomposite and/or electrical hopping conductivity between CuS nanoparticles.

Highly Efficient Self-Healing Multifunctional Dressing with Antibacterial Activity for Sutureless Wound Closure and Infected Wound Monitoring

Wound healing represents a major clinical and public healthcare problem that is frequently challenged by infection risks, detrimental consequences on the surrounding tissues, and difficulties to monitor the healing process. Here we report on a novel self-healing, antibacterial, and multifunctional wound dressing for sutureless wound closure and real-time monitoring of the healing parameters. The self-healing elastomer contains cetyltrimethylammonium bromide (CTAB) and has high mechanical toughness (35 MJ m^-3 ), biocompatibility, and outstanding antibacterial activity (bactericidal rate is ≈90% in 12 h), enabling the wound dressing to effectively inhibit bacterial growth and accelerate infected wound healing. In vivo tests based on full-thickness skin incision model shows that the multifunctional wound dressing can help in contracting wound edges and facilitate wound closure and healing, as could be evidenced by notably dense and well-organized collagen deposition. The test provides an evidence that the integrated sensor array within the multifunctional wound dressing can monitor temperature, pH, and glucose level of the wound area in real-time, providing reliable and timely information of the condition of the wound. Ultimately, the reported multifunctional dressing would be of high value in managing the burden associated with wound healing via personalised monitoring and treatment approaches, digital and other people-centred solutions for health care.

Stretchable and Highly Permeable Nanofibrous Sensors for Detecting Complex Human Body Motion

Wearable strain sensors have been attracting special attention in the detection of human posture and activity, as well as for the assessment of physical rehabilitation and kinematics. However, it is a challenge to fabricate stretchable and comfortable-to-wear permeable strain sensors that can provide highly accurate and continuous motion recording while exerting minimal constraints and maintaining low interference with the body. Herein, covalently grafting nanofibrous polyaniline (PANI) onto stretchable elastomer nanomeshes is reported to obtain a freestanding ultrathin (varying from 300 to 10 000 nm) strain sensor that has high gas permeability (10-33 mg h^-1 ). The sensor demonstrates a low weight and can be directly laminated onto the dynamic human skin for long periods of time. The sensor, which produces an intimate connection with solid or living objects, has a stable performance with excellent sustainability, linearity, durability, and low hysteresis. It exibits excellent performance for continuous interrogation of complex movements, mimicking muscle activities, and resembling brain activity. This includes a very precise discrimination of bending and twisting stimuli at different angles (1-180°) and speeds (3-18 rpm) and very low exertion of counter-interference. These results imply the utility of this appraoch for advanced developments of robotic e-skins or e-muscles.

Transanal endoscopic microsurgery under spinal anaesthesia

Background

Transanal endoscopic microsurgery (TEM) is considered the procedure of choice for rectal adenomas non-amendable for endoscopic excision and for early rectal cancer. TEM may gain more importance in patients who are considered unfit for major surgery. The option of spinal anaesthesia may offer many advantages for patients undergoing TEM while maintaining the principles of complete tumour excision. The aim of this study is to report the outcome of patients undergoing TEM under spinal anaesthesia.

Methods

Demographic and clinical data pertaining patients undergoing TEM under spinal anaesthesia between 2004 and 2015 were retrospectively collected.

Results

A total of 158 TEM procedures were recorded in the study period. Twenty-three patients (15%) underwent the procedure under spinal anaesthesia and were included in the study; 13 of them were male and ten were female. The mean age of the patients was 69.1 ± 10.6 years. Seventeen (74%) rectal lesions were adenomas, two (9%) were adenocarcinoma and four (17%) had involved margins after polypectomy. The mean tumour size was 2.1 cm (range, 0.5-3). Distance from the anal verge was 7.7 ± 2.2 cm. Seventeen (74%) lesions were in the posterior wall. The operative time was 73 min (range, 46-108) No adverse anaesthesia-related events were recorded, and the post-operative pain was reduced. The median time of hospitalisation was 2 days (range, 1-4). No major complications were noted, and the minor complications were treated conservatively. The surgical margins were free of tumour in all cases.

Conclusion

TEM under spinal anaesthesia had short duration of surgery, no increase in operative and post-operative complications or hospital length of stay. Avoiding the use of general anaesthesia, in such challenging procedure, may open new opportunities for patients determined to be unfit for general anaesthesia.

The role of simulation in training breast surgeons: a systematic review

BACKGROUND

As surgical education has evolved, most curricula have favoured a competency-based approach over traditional apprenticeship models. Surgical simulation can be a useful aide in the training of both oncological and reconstructive breast surgery trainees. This review investigates the extent to which simulation of breast surgery procedures has been validated as a training tool.

METHODS

A comprehensive literature search for studies evaluating the objective validity of breast surgery simulators was performed, using MEDLINE, EMBASE and the Cochrane Library databases. Studies assessing construct, concurrent or predictive validity were included, as well as those demonstrating skill acquisition.

FINDINGS

The initial literature search returned 1,625 hits, with only five articles meeting the inclusion criteria. Simulators were designed to train procedures such as breast augmentation, lesion biopsy and excision. Of these, breast biopsy was the most simulated procedure (three studies). Two studies evaluated animal models, two evaluated synthetic models and one study assessed both a synthetic and animal model. Construct validity was confirmed in two studies, concurrent validity in one study and a learning curve demonstrated in another study. No association between experience and performance was seen in the remaining study. The quality of the evidence presented in each article was low due to numerous limitations. Despite the abundance of breast surgery simulators created for trainees, few have been objectively validated and they only cover a narrow range of breast procedures. Although early results are promising, further studies are required before routine use of simulators is considered in breast surgery curricula.

Self-Healing Soft Sensors: From Material Design to Implementation

The demand for interfacing electronics in everyday life is rapidly accelerating, with an ever-growing number of applications in wearable electronics and electronic skins for robotics, prosthetics, and other purposes. Soft sensors that efficiently detect environmental or biological/physiological stimuli have been extensively studied due to their essential role in creating the necessary interfaces for these applications. Unfortunately, due to their natural softness, these sensors are highly sensitive to structural and mechanical damage. The integration of natural properties, such as self-healing, into these systems should improve their reliability, stability, and long-term performance. Recent studies on self-healing soft sensors for varying chemical and physical parameters are herein reviewed. In addition, contemporary studies on material design, device structure, and fabrication methods for sensing platforms are also discussed. Finally, the main challenges and future perspectives in this field are introduced, while focusing on the most promising examples and directions already reported.

Immediate unilateral breast reconstruction and contralateral breast augmentation with bilateral free deep inferior epigastric perforator flaps

A 42-year-old woman was referred for consideration of left-sided mastectomy and immediate reconstruction. She previously had a bilateral breast augmentation using silicone implants. She desired to maintain her breast size and natural appearance. Owing to the availability of sufficient abdominal tissue, the option of an immediate unilateral breast reconstruction and contralateral augmentation with a differentially split deep inferior epigastric perforator flaps was offered to the patient. The patient had a successful reconstructive and contralateral symmetrising procedure with an uneventful postoperative recovery. She was satisfied with her breast size, which was achieved without the use of implants. In selected patients the free deep inferior epigastric perforator flap provides an appropriate option for unilateral breast reconstruction and contralateral breast augmentation. It has numerous advantages including making use of available excess abdominal tissue and avoiding implant related complications.

A Multifunctional Electronic Skin Empowered with Damage Mapping and Autonomic Acceleration of Self-Healing in Designated Locations

Integrating self-healing capabilities into soft electronic devices and sensors is important for increasing their reliability, longevity, and sustainability. Although some advances in self-healing soft electronics have been made, many challenges have been hindering their integration in digital electronics and their use in real-world conditions. Herein, an electronic skin (e-skin) with high sensing performance toward temperature, pressure, and pH levels-both at ambient and/or in underwater conditions is reported. The e-skin is empowered with a novel self-repair capability that consists of an intrinsic mechanism for efficient self-healing of small-scale damages as well as an extrinsic mechanism for damage mapping and on-demand self-healing of big-scale damages in designated locations. The overall design is based on a multilayered structure that integrates a neuron-like nanostructured network for self-monitoring and damage detection and an array of electrical heaters for selective self-repair. This system has significantly enhanced self-healing capabilities; for example, it can decrease the healing time of microscratches from 24 h to 30 s. The electronic platform lays down the foundation for the development of a new subcategory of self-healing devices in which electronic circuit design is used for self-monitoring, healing, and restoring proper device function.

Which patients are less likely to improve after arthroscopic rotator cuff repair?

OBJECTIVE

The aim of this study was to evaluate which specific factors influence the improvement in function and to estimate the time to obtain pain relief following arthroscopic rotator cuff repair.

METHODS

A total of 97 patients (57 men and 40 women; mean age: 55.5 ± 9.3 years) who had arthroscopic rotator cuff repair between 2013 and 2016 were included into the study. Multivariable stepwise analysis included preoperative variables (age, gender, body mass index, comorbidities, occupation and participation in sports, Oxford shoulder score at baseline, preceding injury and duration of preoperative symptoms) and arthroscopic findings (size of rotator cuff tear, pathology of the long head of the biceps and cartilage lesions). The change in the Oxford shoulder score at the last follow-up was modeled as a function of the above predictor variables. The time to regain a visual analogue scale (VAS) under two points following surgery was considered the time to regain substantial pain relief.

RESULTS

The mean follow-up time was 33.2 ± 14.4 months. Twenty three patients had partial thickness and seventy four had full thickness supraspinatus tears. In third of the patients the tears were defined as large full thickness. At the last follow-up the mean Oxford shoulder score improved from 13.8 ± 4.8 to 42.1 ± 7.2 points (P < 0.001). The mean VAS improved from a preoperative score of 6.7 ± 1.3 points to 1.5 ± 0.6 points postoperatively (P < 0.001) and 80 (83%) patients declared they were satisfied to have had the operation. The mean time interval for substantial pain relief was 4.9 ± 3.6 months. Patients with higher preoperative Oxford shoulder score and larger tear size were correlated with lesser improvement in Oxford shoulder score (R = 0.5, P = 0.001).

CONCLUSION

Arthroscopic rotator cuff repair improved pain and function at an average follow-up of three years. A substantial pain relief was regained within five months from surgery. Larger rotator cuff tear size and more favorable preoperative function were predictors of worse postoperative function.

LEVEL OF EVIDENCE

Level IV, Therapeutic study.

Time-space-resolved origami hierarchical electronics for ultrasensitive detection of physical and chemical stimuli

Recent years have witnessed thriving progress of flexible and portable electronics, with very high demand for cost-effective and tailor-made multifunctional devices. Here, we report on an ingenious origami hierarchical sensor array (OHSA) written with a conductive ink. Thanks to origami as a controllable hierarchical framework for loading ink material, we have demonstrated that OHSA possesses unique time-space-resolved, high-discriminative pattern recognition (TSR-HDPR) features, qualifying it as a smart sensing device for simultaneous sensing and distinguishing of complex physical and chemical stimuli, including temperature, relative humidity, light and volatile organic compounds (VOCs). Of special importance, OSHA has shown very high sensitivity in differentiating between structural isomers and chiral enantiomers of VOCs – opening a door for wide variety of unique opportunities in several length scales.

Developing portable, disposable and cost-effective electronics for multifunctional sensing is desirable. Here, the authors present origami-based hierarchical electronics with time-space-resolved high-discriminative pattern recognition (TSR-HDPR) features for multifunctional detection of complex physical and chemical stimuli.

A Freestanding Stretchable and Multifunctional Transistor with Intrinsic Self-Healing Properties of all Device Components

A flexible and stretchable field-effect transistor (FET) is an essential element in a number of modern electronics. To realize the potential of this device in harsh real-world conditions and to extend its application spectrum, new functionalities are needed to be introduced into the device. Here, solution-processable elements based on carbon nanotubes that empower flexible and stretchable FET with high hole-mobility (µ_h ≈ 10 cm² V^-1 s^-1 ) and relatively low operating voltages (<8 V) and that retain self-healing properties of all FET components are reported. The device has repeatable intrinsic and autonomic self-healing ability, namely without use of any external trigger, enabling the restoration of its electrical and mechanical properties, both after microscale damage or complete cut of the device-for example by a scissor. The device can be repeatedly stretched for >200 cycles of up to 50% strain without a significant loss in its electrical properties. The device is applicable in the form of a ≈3 µm thick freestanding skin tattoo and has multifunctional sensing properties, such as detection of temperature and humidity. With this unprecedented biomimetic transistor, highly sustainable and reliable soft electronic applications can be introduced.

Chemically Modified Polyaniline for the Detection of Volatile Biomarkers of Minimal Sensitivity to Humidity and Bending

Flexible sensors can be widely used in future wearable devices to monitor people's health states. However, most of the sensors are sensitive to humidity and bending effects, limiting their application in a real-world environment. A new strategy is proposed for obtaining flexible sensors with good tolerance to humidity. By integrating a hydrophobic layer on the surface of doped polyaniline, a flexible sensor that can resist water response with a concentration up to 350 ppm is developed. Good resilience against mechanical bending is also achieved in this flexible sensor. These results may trigger a renaissance in flexible sensor applications for disease diagnosing by wearable devices.

Laparoscopic Total Mesorectal Excision Following Transanal Endoscopic Microsurgery for Rectal Cancer

BACKGROUND

Patients' selection for transanal endoscopic microsurgery (TEM) depends on diagnostic modalities; however, there are still some limitations in the preoperative diagnosis of rectal lesions, and in some reports, up to third of the adenomas resected by TEM were found to be adenocarcinoma; therefore, salvage radical resection (RR) remains necessary for achieving oncological resection. Salvage RR may encounter some technical problems as the violation of the mesorectum and the scar formation. In this study, we aimed to report the outcome in patients undergoing salvage RR in terms of morbidity and oncological results.

MATERIALS AND METHODS

Demographic and clinical data pertaining to patients undergoing RR following TEM between 2004 and 2014 were retrospectively collected.

RESULTS

One hundred forty one TEM were performed in the study period, 53 (38%) for malignant rectal lesions. Indication for TEM: 15 (28%) benign adenoma, 25 (47%) early rectal cancer, and 13 (25%) had clinical complete response after neoadjuvant radiochemotherapy. Ten (19%) patients had no residual tumor in TEM specimen, 15 (28%) had T1, and 2 of them underwent salvage low anterior resection (LAR). Ten (19%) had T2, 4 had LAR, and 1 had abdominoperineal resection (APR). Five (9%) had a T3, 3 underwent LAR, and 2 had APR. Among the 13 (25%) after chemo-radiotherapy (CRT), 4 had salvage AR. The time from TEM to RR was 47 days (range32-70). Of 16 salvage surgeries, 8 (50%) were laparoscopic. The median operative time was 210 minutes (range165-360). Five patients had protective ileostomy. Rectal perforation occurred in 2 (12%) patients; both had a posterior location, one after CRT. Two (12%) postoperative small-bowl obstruction and three wound infections occurred. There was no perioperative mortality in any of the patients who underwent RR. The final pathology was no residual disease in 9, T3N1 in 1, T3N0 in 3, T2N1 in 1, and T2N0 in 2 patients. Eight (50%) had adjuvant chemotherapy.

CONCLUSION

Laparoscopic total mesorectal excision following TEM seems to be safe, and with no negative impact of the completeness of the resection. The concern of intraoperative specimen perforation is real, and should be dealt with meticulous technique and careful dissection, particularly after CRT.

Infection of PTFE mesh 15 years following pedicled TRAM flap breast reconstruction: mechanism and aetiology

The pedicled transverse rectus abdominis myocutaneous (TRAM) flap procedure is still widely used for breast reconstruction. The repair of the flap harvest site in the transverse rectus abdominis muscle and sheath is often assisted by the use of prosthetic meshes. This decreases the risk of abdominal wall weakness and herniation but, being a foreign body, it also carries the risk of infection. In this report, we describe the case of a 63-year-old patient who, whilst receiving chemotherapy for metastatic breast cancer, presented with an infected polytetrafluoroethylene mesh 15 years after pedicled TRAM flap immediate breast reconstruction. This necessitated mesh removal to treat the infection. Following a thorough review of the English literature, this is the longest recorded presentation of an abdominal prosthetic mesh infection. The mechanism and aetiology of such a late complication are discussed.

The management of pretibial lacerations

Introduction Pretibial lacerations are common injuries, often presenting in the elderly and infirm. Unclear management pathways often result in inappropriate care. We identify patient demographics, morbidity risk factors, injury severity and management options. Materials and methods This retrospective study involved analysing databases and hardcopy notes for patients admitted with pretibial lacerations to Addenbrooke's Hospital, January to December 2012. Microsoft Excel and Fishers exact test were used to analyse the data with a P-value of less than 0.05 representative of statistical significance. Information on patient demographics, site of lesion, preoperative symptoms, management, operative details and clinical outcomes were collected. Results A total of 36 patients were identified; the mean age was 79 years (± 16 years, 1 standard deviation) with a three to two female to male preponderance; 57% of injuries were caused by mechanical fall, 33% traumatic blunt impact and 7% road traffic accidents. American Society of Anesthesiologists physical status classification was 43% level III, 40% II, 9% I and 9% IV. Dunkin classification of severity was 33% grade III, 30% grade I, 24% grade IV and 12% grade II. Median inpatient duration was 11 days for surgically managed compared with 15 days for conservatively managed patients. Discussion Pretibial lacerations tend to affect the elderly. Management is compounded by polypharmacy and comorbidities. If inadequately managed, such injuries can adopt characteristics of chronic wounds, with lengthy inpatient stays. Surgical intervention may be appropriate where injuries are severe and the patient stable enough for theatre. Conclusions We believe that surgical management with autologous tissue repair, with minimal delay between presentation and theatre, is warranted for extensive injuries wherever possible, with conservative management used for predominantly less extensive pretibial lacerations.

[COMPARISON OF QUALITY OF COLONOSCOPY IN AN ACADEMIC HOSPITAL VS. A COMMUNITY HOSPITAL OUTPATIENT SERVICE]

BACKGROUND

Extensive use of colonoscopy in hospitals and community clinics has highlighted the need to assess the quality of the procedures in order to reduce costs and increase their efficiency.

OBJECTIVES

This institutional review board (IRB)-approved study aimed to compare the quality of colonoscopies performed in a teaching hospital to those performed at a community health service.

METHODS

Demographic information, time of procedure, indications, quality of bowel preparation, premedication, depth of examination, polyp detection, biopsies and followup recommendations were retrospectively obtained from 700 colonoscopy reports from the Rambam Healthcare Campus and 824 colonoscopy reports from Elisha. This data was compared to relevant literature benchmarks.

RESULTS

There was no statistically significant difference between the hospital vs. community endoscopy services in the patients' demographics, depth of examination (92.4% vs. 94.1% complete), polyp detection rate (29.1% vs. 26.8%) and biopsies in patients with diarrhea (75% vs. 67%). Indications for colonoscopy differed: gastrointestinal bleeding was more common at the hospital, while screening was more common in the community. Premedication varied: more fentanyl and dormicum and less propofol were used in the community. Good bowel preparation was more frequent in the community (68.8% vs. 47.2% in hospital, p<0.0001). Follow-up recommendations were documented more often in the community (74% vs. 53% in hospital, p<0.0001). The range for many quality indicators (QIs) varied greatly amongst physicians.

CONCLUSIONS

Remediation of weaker areas seems feasible through upgrading electronic medical records and increasing awareness of quality indicators (Qis). Colonoscopies performed in both hospital and community services were of good quality compared to the relevant literature, with significant variations in some QIs.

Transanal Endoscopic Microsurgery Combined with Laparoscopic Colectomy for Synchronous Colorectal Tumors: A Word of Caution

BACKGROUND

The incidence of malignant synchronous colorectal tumors (SCRT) is between 2% and 5%, and the association of synchronous adenomatous polyps in colon cancer has been reported to be 15%-50%. Surgical resection is the primary treatment option for SCRT not amendable to endoscopic resection. Lesions in adjacent segments are usually treated with more extensive resection; however, there is still some controversy on how to best treat synchronous lesions in separate segments, especially when the rectum is involved. In this study, we aimed to report the outcome of patients with SCRT treated by laparoscopic colectomy combined with Transanal Endoscopic Microsurgery.

METHODS

Data pertaining patients undergoing combined colectomy and Transanal Endoscopic Microsurgery (TEM) between 2004 and 2014 were retrospectively collected.

RESULTS

141 TEM performed in the study period, 9 (6.5%) with combined laparoscopic colectomy were included. Mean age was 69.1 ± 10.6 years. There were 6 (66%) right, 2 (22%) left, and one (11%) sigmoid colectomy. All rectal lesions were benign adenomas, with mean tumor size 2.5 cm, and distance from the verge 9 ± 2.5 cm. Lesions were located in lateral rectal wall in 4, posterior in 4, and anterior in one case. Seven patients had the colectomy before TEM, and 2 had the TEM first. Mean operative time was 245 minutes (range 185-313) for the combined procedures. Median time of hospitalization was 6 days (range 4-11). Six patients (66%) had prolonged postoperative diarrhea. The final rectal pathology reports were adenoma with high-grade dysplasia (HGD) in 5 patients and adenoma with low-grade dysplasia in four cases. The colon pathology was T1 N0 in 3, T2 N0 in one, T3 N1 in one, adenoma with HGD in 2, and no residual tumor in 2 patients. Two patients underwent re-TEM for recurrent adenoma of rectum at 14 and 18 months postoperatively.

CONCLUSION

The combination of TEM with laparoscopic colectomy is feasible and should be kept in mind as an alternative procedure in case of SCRT. However, more strict selection criteria should be considered and the disadvantages should be discussed with the patient.

Retentive Cup Arthroplasty in Selected Hip Fracture Patients-A Prospective Series With a Minimum 3-Year Follow-Up

Objective:

To evaluate the efficacy of the use of retentive cup primary total hip replacement (THR) in high-dislocation risk subcapital fracture patients.

Methods:

During the years 2008 to 2012, 354 patients with displaced subcapital fracture were operated at our institute. The patients were selected to undergo primary constrained THR according to the following criteria: (1) a preinjury grade 4 or more on the Functional Independence Measure mobility item “5. Locomotion: walking/wheelchair” and grade 4 is defined as “4. Minimal assistance Requiring incidental hands-on help only” (patient performs >75% of the task) and (2) a disease leading to poor motor control. Exclusion criteria were normal muscular control and known infection of the involved joint.

Results:

Of the 354 patients, 87 fulfilled the inclusion criteria and underwent constrained total hip. Average age was 78 years with a female predominance (73%). Fifteen patients had prior hemiparesis, 19 had Parkinson disease, and 35 had generalized sarcopenia. Eighty-five patients had an uneventful recovery, with an average Hip Disability and Osteoarthritis Outcome Score (HOOS) of 76 ± 7 at 2 years. In 2 patients, the prostheses dislocated. In both cases, the dislocation was due to ring displacement and the inner head dislocated. One case was infected and the patient was treated by a Girdlestone procedure. In the other case, the prosthetic head was revised. The patient remained asymptomatic and at 4-year follow-up had an HOOS of 85.

Discussion:

It appears that constrained prosthesis is a suitable treatment for patients with poor muscular control having subcapital fractures. The functional results appear to be superior to those of bipolar arthroplasty and similar to the results of primary total hip arthroplasty while the dislocation risk is <3%.

Conclusion:

Semielective total hip arthroplasty using a retentive cup liner appears to offer good functional results with a low dislocation rate in patients with poor muscular control.

Mastectomy and reconstruction in stage IV breast cancer: a survey of UK breast and plastic surgeons

The number of women with stage IV disease who have breast reconstruction is small. The primary aim of this study was to examine opinions as to the appropriateness of breast reconstruction in this group. The Association of Breast Surgeons (ABS) and the British Association of Plastic Reconstructive and Aesthetic Surgeons (BAPRAS) were invited to take part in an online survey. Of the respondents, 78.7% would operate on the primary tumour. Plastic surgeons showed a propensity for immediate reconstruction compared to their breast surgery colleagues, and 26.3% of breast surgeons would not offer reconstruction at all. Immediate latissimus dorsi (LD) flap and implant were the favoured method in early stage disease with delayed LD and implant the most popular option for stage IV disease. As survival figures continue to improve, the number of patients requesting reconstruction is likely to increase. Further debate will be necessary in anticipation of future service development.

Hand washing and use of gloves while managing patients receiving mechanical ventilation in the ICU

STUDY OBJECTIVE

To evaluate the effectiveness of warning labels permanently attached to mechanical ventilators in improving the practice of hand washing and use of gloves by respiratory care practitioners (RCPs) in the ICU.

DESIGN

The study consisted of two 4-week periods. Daily observations of hand washing and use of gloves by RCPs were made over four 1-h observation periods. Prior to the first 4-week period, the importance of hand washing and use of gloves was presented to all staff. At the end of the first period, "Wash Hands Use Gloves" labels were permanently placed on all ventilators in the ICU. The RCPs were not aware they were being observed for hand washing and use of gloves in either period.

MEASUREMENTS AND RESULTS

The total number of encounters between the RCPs and patients as well as the rates of hand washing and use of gloves were obtained during the study. The rates of hand washing and use of gloves were significantly higher during the second period when labels were attached to the ventilators, as compared to the rates during the first period: hand washing, 92% vs 46% (p < 0.05); use of gloves, 92% vs 43% (p < 0.05), respectively. During the first period, the rates of pre-encounter hand washing (78%, 48%, 27%, and 29% in weeks 1 through 4, respectively) and the use of gloves (56%, 37%, 32%, and 45% in weeks 1 through 4, respectively) were primarily declining. This was not observed during the second period of the study (94%, 88%, 95%, and 92% in weeks 1 through 4, respectively) for the rates of pre-encounter hand washing and the use of gloves.

CONCLUSIONS

Simple measures such as the placement of warning labels on mechanical ventilators can significantly improve hand washing and use of gloves by RCPs in the ICU.

Excitatory interactions between phrenic motoneurons: intracellular study in the cat

1. Intracellular recordings were made from 220 Phrenic Motoneurons (PM) in anaesthetized, spontaneously breathing cats, deafferented from C3 to C7, in order to look for somatic events related to the Recurrent Responses (RR) evoked in PM axons by repetitive stimulation of the phrenic nerve. RR appear sporadically at a constant latency, originate from a spinal nicotinic mechanism and can be evoked in a PM without the presence of an antidromic volley in its axon (Khatib et al. 1986). 2. Using stimuli effective for eliciting RR in axons, we failed to observe intracellularly somatic events corresponding to RR after the occurrence of an antidromic action potential. RR were observed extracellularly in two cases, but in both cases the recording originated from axons. 3. We attempted to elicit somatic RR without a preceding antidromic action potential, using either parathreshold stimulation of the impaled PM, or suprathreshold stimulation of a phrenic strand which excluded the axon of the impaled PM. In both cases, RR-like events, with very stable latencies, appeared sporadically in 4/142 and 2/15 PMs respectively. 4. Parathreshold stimuli or stimulation of a strand were coupled with averaging of the synaptic noise in order to look for small events temporally related to the stimuli. Short latency small depolarizations, looking-like recurrent EPSPs, were revealed in 22/142 and 5/15 PMs respectively. 5. These results confirm the existence of interrelations between PMs, providing for re-excitation and coupling within the phrenic pool, in addition to centrally imposed synchronization.

Central drive on Renshaw cells coupled with phrenic motoneurons

In anesthetized spontaneously breathing cats (C4-C5 deafferentation), recurrent inhibition of phrenic motoneurons was analyzed by studying either recurrent IPSPs in phrenic motoneurons, or Renshaw cell discharges evoked by C5 phrenic nerve stimulation. Of 90 intracellularly recorded phrenic motoneurons, 7 motoneurons showed evoked recurrent IPSPs with stimulation of C5 phrenic axons subthreshold for eliciting antidromic activation of the motoneuron from which intracellular recording was done. These IPSPs could be reversed by imposed hyperpolarization of the motoneuron, and were of greater amplitude during inspiration than during expiration. Within the phrenic nucleus, interneurons were classified as Renshaw cells if they responded to C5 phrenic axon stimulation with a typical high frequency burst of potentials. Reactivity of these Renshaw cells was related to the respiratory cycle, number of spikes in the burst being greater during inspiration than during expiration. Injection of a nicotinic cholinergic blocker (mecamylamine) decreased responses of Renshaw cells but the respiratory modulation was still present. Some Renshaw cells (18/33) were spontaneously active during inspiration. Their activity was generally maximal during the last third of inspiration. Since: spontaneous activity of Renshaw cells is related to the respiratory drive; persists after C7 spinal transection and after mecamylamine poisoning of the axonal recurrent pathway; and might appear before sustained phrenic activity, the assumption of a central respiratory drive impinging on the Renshaw cells has to be retained.

Excitatory interactions between phrenic motoneurons in the cat

Interactions between phrenic motoneurons have been analysed in anaesthetized, paralyzed cats after C3 to C7 deafferentation. Effects of electrical stimulation of the C5 phrenic axons have been studied on thin filaments dissected from the stimulated nerve. Repetitive stimulation could elicit, after the primary direct response of the stimulated axons, a secondary response named Recurrent Response, RR. RRs have been obtained in 117/186 phrenic axons. They appear sporadically (mean occurrence: 3.75 RRs elicited by 100 shocks of stimulation) at a constant latency. They originate from a spinal mechanism since they persist after C2 transection and disappear after section of the ventral roots. The mechanism responsible for RR shows spatial and temporal facilitation. The RR probability increases with the number of antidromically invaded motoneurons as revealed by changes either of stimulation intensity or of central respiratory drive. However, RR could be evoked in a motoneuron without an antidromic volley in its axon. Systemic injections of nicotinic blocking drugs such as dihydro-beta-erythroidine or mecamylamine decrease or suppress the occurrence of RR; therefore, cholinergic synapses are involved in the RR generating process. RR are assumed to be due to direct excitatory interactions between homonymous motoneurons. Recurrent axon collaterals impinging directly on neighbouring motoneurons would link together the different motoneurons of the phrenic pool. The functional significance of this phenomenon is discussed.

Central determination of recruitment order: intracellular study of phrenic motoneurons

Simultaneous recordings were made intracellularly from phrenic motoneurons (PMs) and extracellularly from their central drivers, the inspiratory bulbospinal neurons (IBSNs) of the dorsal respiratory nucleus. On the basis of their order of recruitment from the beginning of inspiration (as estimated by the phrenic discharge). PMs and IBSNs were classified as early (E) or late (L) units. Unitary excitatory postsynaptic potentials (EPSPs) evoked in the PM by the IBSN were frequently observed between IBSNs and PMs with a similar recruitment, both E, 11/28 or both L, 10/13, and were scarce between IBSNs and PMs with different recruitment. E and L, 8/28, or L and E, 2/11. Since measured membrane resistances of E and L PMs were not statistically different, the recruitment order of PMs may be considered as mainly determined by the timing (E or L) of the central drive that they received.

[Long-term results following cholesteatoma surgery]

A long-term review of 140 ears in 133 patients was carried out. All ears had first been operated on in 1971 and 1972 for cholesteatoma in the E.N.T. clinic. A closed technique was used in 110 ears and in the remaining 30 ears an open technique, depending on the pneumatisation of the mastoid, the extent of the cholesteatoma, tubal function and the age and social circumstances of the patient. At that time, second-look operations were carried out on relatively few patients after a closed operation. While the short-term results were favourable, recurrent cholesteatomas still developed 8 to 10 years later; 9 were discovered at this review alone. The long-term incidence of recurrence was 25%. Recurrent cholesteatomas were found in 57% of patients who were first operated on for a cholesteatoma before the age of 21, 24% of those between 21 and 40, and 11% of those between 41 and 60. These results reaffirm the necessity for a planned second-look operation in all young patients and also the importance of outpatient follow-up over many years.

Spontaneous respiratory activity of phrenic and intercostal Renshaw cells

Activity of Renshaw cells evoked by electrical stimulation of either phrenic or internal intercostal axons was extracellularly recorded in anaesthetized spontaneously breathing cats. The response of all the studied units to antidromic invasion of the corresponding motoneurones was related to the respiratory cycle and some units displayed spontaneous respiratory activity. Recurrent IPSPs were recorded on phrenic and intercostal motoneurones.