Surgical complications in the first and second semesters of the general surgery medical residence. A study of 14063 cases.

OBJECTIVE: To evaluate whether the rate of surgical complications is higher during the first semester of the General Surgery residency in the largest hospital complex in Latin America. During this period, students are expected to have less experience in carrying out procedures. METHODS: During a period of two years, all General Surgery resident doctors at the Hospital das Clínicas of the Faculty of Medicine of the University of São Paulo, made a notification of all the procedures they performed (n = 14.063), containing information such as name of the procedure, date, who participated, complications, among others. These data were analyzed with the purpose of evaluating the variation in the rate of complications throughout the year. RESULTS: There was a 52 % increase in the rate of complications in the first academic semester when compared to the second semester. This phenomenon was observed in resident doctors in the first and second years of residency. Furthermore, it was observed that second-year residents remain with high rates of complications, in some procedures, for a longer time than first-year residents. Furthermore, the first three months (March, April and May) seem to have the highest complication rates of the entire year. CONCLUSION: The impact of these complications can affect several health services and the increase in surgical complications in the first half of the year must be monitored by institutions, in order to control this phenomenon.

Surgical complications in the first and second semesters of the general surgery medical residence. A study of 14063 cases

Abstract Objective: To evaluate whether the rate of surgical complications is higher during the first semester of the General Surgery residency in the largest hospital complex in Latin America. During this period, students are expected to have less experience in carrying out procedures. Methods: During a period of two years, all General Surgery resident doctors at the Hospital das Clínicas of the Faculty of Medicine of the University of São Paulo, made a notification of all the procedures they performed (n = 14.063), containing information such as name of the procedure, date, who participated, complications, among others. These data were analyzed with the purpose of evaluating the variation in the rate of complications throughout the year. Results: There was a 52 % increase in the rate of complications in the first academic semester when compared to the second semester. This phenomenon was observed in resident doctors in the first and second years of residency. Furthermore, it was observed that second-year residents remain with high rates of complications, in some procedures, for a longer time than first-year residents. Furthermore, the first three months (March, April and May) seem to have the highest complication rates of the entire year. Conclusion The impact of these complications can affect several health services and the increase in surgical complications in the first half of the year must be monitored by institutions, in order to control this phenomenon.

Challenges to implement laparoscopic appendectomy as the first-line treatment for acute appendicitis: a fifteen-year experience in a tertiary hospital in Brazil.

BACKGROUND: the barriers to implement emergency laparoscopy in public teaching hospitals involve issues such as resident learning curves and resource costs and availability. This study was designed to describe the issues facing the implementation of laparoscopic approach for acute appendicitis over 15 years in a single academic center in Brazil. MATERIALS AND METHODS: retrospective study of patients undergoing emergency appendectomy from 2004 to 2018. Clinical data were compared to four major actions implemented in the emergency surgical service: minimally invasive surgery training for residents (2007), laparoscopic stump closure using metal clips (2008), 24/7 availability of laparoscopic instruments for emergency surgeries (2010), and third-party contract for maintenance of the laparoscopic instruments and implementation of polymeric clips for stump closure (2013). We evaluated the increase in laparoscopic appendectomy after the implementation of those major changes. RESULTS: we identified 1168 appendectomies during the study period, of which 691 (59%), 465 (40%), and 12 (1%) were open, laparoscopic, and converted, respectively. The implementation of the major changes since 2004 resulted in an increase of laparoscopic appendectomies from 11% in 2007 to 80% in 2016. These actions were decisive in the widespread use of laparoscopy for acute appendicitis (p<0.001). The standardization of the hem-o-lok clip in the treatment of the appendiceal stump made the procedure more feasible, reducing the surgical time using laparoscopic access and increasing the team's adherence, so that this became the route of choice in about 85% of cases in the period from 2014 to 2018, 80% performed by 3rd year resident physicians. No intraoperative complications were noted related to laparoscopic access, even in more complicated appendicitis. There was no mortality reported, no reoperations or readmissions to hospital during a 30-day postoperative period. CONCLUSION: the development of a feasible, reproducible, and safe technical standardization, associated with continuous cost optimization, are the cornerstones for a consistent and viable change in the current practice for appendectomies in middle and lower-income countries.

Could trauma laparoscopy be the standard of care for hemodynamically stable patients? A retrospective analysis of 165 cases.

BACKGROUND: Trauma laparoscopy may provide a less invasive alternative to laparotomy by providing accurate diagnosis and minimally invasive management of selected trauma patients. The risk of missing injuries during the laparoscopic evaluation still refrains surgeons from using this approach. Our aim was to evaluate feasibility and safety of trauma laparoscopy in selected patients. METHODS: We performed a retrospective review of hemodynamically trauma patients who underwent laparoscopic management in a tertiary center in Brazil due to abdominal trauma. Patients were identified by searching through the institutional database. We collected demographic and clinical data, focusing on avoidance of exploratory laparotomy, and missed injury rate, morbidity, and length of stay. Categorical data were analyzed using Chi-square, while numerical comparisons were performed using Mann-Whitney and Kruskal-Wallis test. RESULTS: We evaluated 165 cases, of which 9.7% needed conversion to an exploratory laparotomy. One-hundred and twenty-one patients (73%) had at least one intrabdominal injury. Two missed injuries to retroperitoneal organs were identified (1.2%), of which only one was clinically relevant. Three patients died (1.8%), one of which was due to complications from an intestinal injury after conversion. No deaths were related to the laparoscopic approach. CONCLUSION: In selected hemodynamically stable trauma patients, the laparoscopic approach is feasible and safe, and reduces the need for exploratory laparotomy and its associated complications.

Challenges to implement laparoscopic appendectomy as the first-line treatment for acute appendicitis: a fifteen-year experience in a tertiary hospital in Brazil / Barrreiras na implementação da apendicectomia laparoscópica como tratamento de escolha para apendicite aguda: experiência de 15 anos em hospital terciário no Brasil

ABSTRACT Background: the barriers to implement emergency laparoscopy in public teaching hospitals involve issues such as resident learning curves and resource costs and availability. This study was designed to describe the issues facing the implementation of laparoscopic approach for acute appendicitis over 15 years in a single academic center in Brazil. Materials and Methods: retrospective study of patients undergoing emergency appendectomy from 2004 to 2018. Clinical data were compared to four major actions implemented in the emergency surgical service: minimally invasive surgery training for residents (2007), laparoscopic stump closure using metal clips (2008), 24/7 availability of laparoscopic instruments for emergency surgeries (2010), and third-party contract for maintenance of the laparoscopic instruments and implementation of polymeric clips for stump closure (2013). We evaluated the increase in laparoscopic appendectomy after the implementation of those major changes. Results: we identified 1168 appendectomies during the study period, of which 691 (59%), 465 (40%), and 12 (1%) were open, laparoscopic, and converted, respectively. The implementation of the major changes since 2004 resulted in an increase of laparoscopic appendectomies from 11% in 2007 to 80% in 2016. These actions were decisive in the widespread use of laparoscopy for acute appendicitis (p<0.001). The standardization of the hem-o-lok clip in the treatment of the appendiceal stump made the procedure more feasible, reducing the surgical time using laparoscopic access and increasing the team's adherence, so that this became the route of choice in about 85% of cases in the period from 2014 to 2018, 80% performed by 3rd year resident physicians. No intraoperative complications were noted related to laparoscopic access, even in more complicated appendicitis. There was no mortality reported, no reoperations or readmissions to hospital during a 30-day postoperative period. Conclusion: the development of a feasible, reproducible, and safe technical standardization, associated with continuous cost optimization, are the cornerstones for a consistent and viable change in the current practice for appendectomies in middle and lower-income countries.

RESUMO Introdução: o presente estudo tem como objetivo avaliar as medidas que permitiram a implementação de cirurgias laparoscópicas de urgência em hospital de ensino médico ao longo de 15 anos. Método: foi realizado estudo clínico retrospectivo de pacientes submetidos a Apendicectomia aberta ou Laparoscópica no período de 15 anos (2004 a 2018). Os dados clínicos foram confrontados com as ações implementadas: 1) Treinamento dos médicos residentes em cirurgia minimamente invasiva (2007); 2) Uso do endoclip para tratamento do coto apendicular (2008); 3) Disponibilidade do set de laparoscopia em tempo integral para o Pronto Socorro (2010); e, 4) Terceirização do serviço de manutenção do set e materiais de vídeo e uso do endoclip Hem-o-lok® para tratamento do coto apendicular (2013). Resultados: foram realizadas 1.168 cirurgias, das quais 691 abertas (59%), 465 laparoscopias (40%) e 12 convertidas (1%). O treinamento da equipe levou à realização de 11% de laparoscopia (2007) e o uso do endoclip para tratamento do coto apendicular para 16% (2008). Com a disponibilização do set de vídeo em tempo integral para o Pronto Socorro a partir de 2011, houve aumento de laparoscopias para 26% (2012). A padronização do endoclip Hem-o-lok® no tratamento do coto apendicular aumentou para 85% e a partir de 2016 foi realizado em todos os casos, sem complicação relacionada ao seu uso, mesmo em apendicites complicadas. Conclusão: o emprego da laparoscopia no serviço de urgência envolve além do treinamento da equipe cirúrgica, investimento tecnológico contínuo e uso de técnicas que sejam factíveis, viáveis e seguras.

Out-of-equilibrium dynamics driven by photoinduced charge transfer in CsCoFe Prussian blue analogue nanocrystals.

In this paper we study the out-of-equilibrium dynamics associated with photoinduced charge-transfer (CT) in cyanide-bridged Co-Fe Prussian blue analogue nanocrystals. In these coordination networks, the structural trapping of the photoinduced CT polaron involves local electronic and structural reorganizations. Femtosecond X-ray and optical absorption spectroscopies show that the local structural trapping process occurs on similar timescale for particles with 11 nm and 70 nm sizes. The local photoinduced spin transition, elongating the Co-N bonds and driving the CoIIIFeII → CoIIFeIII CT, activates coherent lattice torsion modes. The elastic deformation waves, launched by these bond elongations, drive macroscopic volume expansion and breathing of the particles. The timescale of this macroscopic deformation depends strongly on the size of the particle, which is more evidence of the multiscale nature of photoinduced phenomena in molecular materials.

Which Model Is Better to Teach How to Perform Tube Thoracostomy: Synthetic, Cadaver, or Animal?

INTRODUCTION: The lack of standardized skill training reported by medical students in performing tube thoracostomies may be associated with higher complications. The ideal training model is yet to be determined. This study sought to evaluate three different models. METHODS: Between 2015 and 2017, 204 last-year medical students of Universidade de São Paulo with no prior training in tube thoracostomy were randomized into three groups: cadaver, pig, and synthetic models. All groups performed 1-d tube thoracostomy hands-on training and a 40-min theoretical class. The knowledge acquisition was measured by a comparison between a theoretical test before and 3 wk after the class, and the skills improvement was evaluated by a comparison between the skills test on the same day of the hands-on training and another after 24 wk (the retention skill test). A questionnaire was submitted to evaluate their satisfaction rate and self-reported confidence, as per a Likert scale. RESULTS: The theoretical post-test score was higher compared to the pretest score in all groups (P < 0.001). The retention skills test in the cadaver and synthetic groups decreased compared to the skills test (P = 0.01 and P = 0.007, respectively). There was no difference between the groups either in the theoretical test or in the skills test. Student satisfaction was higher in the cadaver and pig groups. The confidence perception increased in all groups after the training. CONCLUSIONS: The models used for tube thoracostomy training appear to have a similar impact on skills retention, knowledge acquisition, and confidence. Although the satisfaction rate is lower for the synthetic model, it has no biological risk or ethical issues and is more feasible.

Strain wave pathway to semiconductor-to-metal transition revealed by time-resolved X-ray powder diffraction.

One of the main challenges in ultrafast material science is to trigger phase transitions with short pulses of light. Here we show how strain waves, launched by electronic and structural precursor phenomena, determine a coherent macroscopic transformation pathway for the semiconducting-to-metal transition in bistable Ti3O5 nanocrystals. Employing femtosecond powder X-ray diffraction, we measure the lattice deformation in the phase transition as a function of time. We monitor the early intra-cell distortion around the light absorbing metal dimer and the long range deformations governed by acoustic waves propagating from the laser-exposed Ti3O5 surface. We developed a simplified elastic model demonstrating that picosecond switching in nanocrystals happens concomitantly with the propagating acoustic wavefront, several decades faster than thermal processes governed by heat diffusion.

"Pop in a scope": attempt to decrease the rate of unnecessary nontherapeutic laparotomies in hemodynamically stable patients with thoracoabdominal penetrating injuries.

BACKGROUND: Management of patients with thoracoabdominal penetrating injuries is challenging. Thoracoabdominal penetrating trauma may harbor hollow viscus injuries in both thoracic and abdominal cavities and occult diaphragmatic lesions. While radiological tests show poor diagnostic performance in these situations, evaluation by laparoscopy is highly sensitive and specific. Furthermore, minimally invasive surgery may avoid unnecessary laparotomies, despite concerns regarding complication and missed injury rates. The objective of the present study is to evaluate the diagnostic and therapeutic performance of laparoscopy in stable patients with thoracoabdominal penetrating injuries. METHODS: Retrospective analysis of hemodynamically stable patients with thoracoabdominal penetrating wounds was managed by laparoscopy. We collected data regarding the profile of the patients, the presence of diaphragmatic injury, perioperative complications, and the conversion rate. Preoperative imaging tests were compared to laparoscopy in terms of diagnostic accuracy. RESULTS: Thirty-one patients were included, and 26 (84%) were victims of a stab wound. Mean age was 32 years. Ninety-three percent were male. Diaphragmatic lesions were present in 18 patients (58%), and 13 (42%) had associated injuries. There were no missed injuries and no conversions. Radiography and computerized tomography yielded an accuracy of 52% and 75%, respectively. CONCLUSION: Laparoscopy is a safe diagnostic and therapeutic procedure in stable patients with thoracoabdominal penetrating wound, with low complication rate, and may avoid unnecessary laparotomies. The poor diagnostic performance of preoperative imaging exams supports routine laparoscopic evaluation of the diaphragm to exclude injuries in these patients.

Photoselective MLCT to d-d pathways for light-induced excited spin state trapping.

We use femtosecond optical pump-probe spectroscopy to study the Light Induced Excited Spin State Trapping (LIESST) dynamics in an FeII spin-crossover material. In these systems, LIESST derives from fast molecular switching induced by light from low (LS, S = 0) to high spin (HS, S = 2) states, as reported for molecules in solution as well as in the solid state. Since the direct LS-to-HS conversion is forbidden by selection rules, the switching dynamics involves intermediate electronic states such as metal-to-ligand charge transfer (MLCT) or ligand-field excited states of singlet or triplet nature. In addition, the HS state is structurally trapped by the elongation of the metal-ligand bond, which is accompanied by the coherent activation and damping of the molecular breathing mode. The ultrafast LIESST dynamics was mainly investigated in FeN6 ligand field systems with almost octahedral symmetry, under MLCT excitation. Our recent study on the FeII(pap-5NO2)2 spin-crossover material, with a FeIIN4O2 ligand field of C2 symmetry, has shown that in addition to MLCT bands, optical excitation, through quite intense and low-energy shifted d-d bands, can also drive LIESST. Compared to MLCT, d-d excitation involves shorter-lived intermediates, drives faster LS-to-HS switching, and enhances the coherent structural dynamics. In this paper, we present an ultrafast study of the pump wavelength dependence of LIESST and we evidence a photoselective crossover from the MLCT to the d-d pathways.

Efficacy of a Novel Surgical Manikin for Simulating Emergency Surgical Procedures.

The practical component of the Advanced Trauma Life Support (ATLS®) course typically includes a TraumaMan® manikin. This manikin is expensive; hence, a low-cost alternative (SurgeMan®) was developed in Brazil. Our primary objective was to compare user satisfaction among SurgeMan, TraumaMan, and porcine models during the course. Our secondary objective was to determine the user satisfaction scores for SurgeMan. This study included 36 ATLS students and nine instructors (4:1 ratio). Tube thoracostomy, cricothyroidotomy, pericardiocentesis, and diagnostic peritoneal lavage were performed on all the three models. The participants then rated their satisfaction both after each activity and after the course. The porcine and TraumaMan models fared better than SurgeMan for all skills except pericardiocentesis. In the absence of ethical or financial constraints, 58 per cent of the students and 66 per cent of the instructors indicated preference for the porcine model. When ethical and financial factors were considered, no preference was evident among the students, whereas 66 per cent of instructors preferred SurgeMan over the others. The students gave all three models an overall adequacy rating of >80 per cent; the instructors gave only the animal models an adequacy rating of <80 per cent. Although the users were more satisfied with TraumaMan than with SurgeMan, both were considered acceptable for the ATLS course.

Comparison of structural dynamics and coherence of d-d and MLCT light-induced spin state trapping.

Light-induced excited spin state trapping (LIESST) in FeII spin-crossover systems is a process that involves the switching of molecules from low (LS, S = 0) to high spin (HS, S = 2) states. The direct LS-to-HS conversion is forbidden by selection rules, and LIESST involves intermediate states such as 1,3MLCT or 1,3T. The intersystem crossing sequence results in an HS state, structurally trapped by metal-ligand bond elongation through the coherent activation and damping of molecular breathing. The ultrafast dynamics of this process has been investigated in FeN6 ligand field systems, under MLCT excitation. Herein, we studied LIESST in an FeIIN4O2 spin-crossover material of lower symmetry, which allowed for quite intense and low-energy shifted d-d bands. By combining ab initio DFT and TD-DFT calculations and fs optical absorption measurements, we demonstrated that shorter intermediates enhanced coherent structural dynamics, and d-d excitation induced faster LS-to-HS switching, compared to MLCT.

Safety in selective surgical exploration in penetrating neck trauma.

BACKGROUND: Selective management of penetrating neck injuries has been considered the standard of care with minimal risks to patient safety. In a previous non-randomized prospective study conducted at our center, selective management proved to be safe and reduced unnecessary exploratory cervicotomies. In the present study, the role of clinical examination and selective diagnostic tests were assessed by reviewing demographic and clinical data. A comparison of results between two groups (mandatory surgical exploration versus selective surgical exploration) was made to check the safety of selective management in terms of the rates of morbidity and mortality. METHODS: A retrospective analysis at the Emergency Department of the Hospital das Clínicas of the University of Sao Paulo was performed by a chart review of our trauma registry, identifying 161 penetrating neck trauma victims. RESULTS: Of the 161 patients, 81.6 % were stabbed and 18.4 % had gunshot injuries. Stratifying the wound entry points by neck zones, we observed that zone I was penetrated in 32.8 %, zone II in 44.1 % and zone III in 23.1 % of all the cases. Thirty one patients (19.2 %) had immediate surgical exploration, which had a mean length of stay of 6 days, a complication rate of 12.9 % and a mortality rate of 9.4 %. Of the 130 who underwent selective surgical exploration 34 (26.1 %) required operative procedures after careful physical examination and diagnostic testing based on clinical indications. The mean length of stay for the selective surgical exploration group was 2 days with a complication rate of 17.6 % with no mortality, and virtually all of them were related to associated injuries in distant body segment. No statistical significance was found comparing mortality and complication rates between the two groups. Selective approach avoided 59 % of unnecessary exploratory cervicotomies. CONCLUSION: Careful evaluation of asymptomatic and stable patients with minor signs of injury can safely avoid unnecessary neck explorations with low rates of morbidity. This should be the standard management of such patients.

Activation of coherent lattice phonon following ultrafast molecular spin-state photo-switching: A molecule-to-lattice energy transfer.

We combine ultrafast optical spectroscopy with femtosecond X-ray absorption to study the photo-switching dynamics of the [Fe(PM-AzA)2(NCS)2] spin-crossover molecular solid. The light-induced excited spin-state trapping process switches the molecules from low spin to high spin (HS) states on the sub-picosecond timescale. The change of the electronic state (<50 fs) induces a structural reorganization of the molecule within 160 fs. This transformation is accompanied by coherent molecular vibrations in the HS potential and especially a rapidly damped Fe-ligand breathing mode. The time-resolved studies evidence a delayed activation of coherent optical phonons of the lattice surrounding the photoexcited molecules.

Cooperative elastic switching vs. laser heating in [Fe(phen)2(NCS)2] spin-crossover crystals excited by a laser pulse.

Spin-crossover crystals show multi-step responses to femtosecond light excitation. The local molecular photo-switching from low to high spin states occurs on sub-picosecond timescale. It is followed by additional conversion due to elastic (ns) and thermal (µs) effects. In [Fe(phen)2(NCS)2] crystals discussed herein, the thermal switching can be made unobtrusive for the investigation of cooperative elastic switching. We evidence a cooperative transformation induced by lattice expansion through elastic coupling between molecules in the crystal, where up to 3 molecules are transformed per photon.

Open abdomen management: single institution experience.

OBJECTIVE: to evaluate the outcome of abdominal wall integrity of both techniques. METHODS: a retrospective study was carried out at the Hospital das Clínicas, Faculdade de Medicina, Universidade de São Paulo, identifying the patients undergoing temporary abdominal closure (TAC) from January 2005 to December 2011. Data were collected through the review of clinical charts. Inclusion criteria were indication of TAC and survival to definitive abdominal closure. In the post-operative period only a group of three surgeons followed all patients and performed the reoperations. RESULTS: Twenty eightpatients were included. The difference in primary closure rates and mean time for fascial closure did not reach statistical significance (p=0.98 and p=0.23, respectively). CONCLUSION: VAC and Bogota Bag do not differ significantly regarding the outcome of abdominal wall integrity, due to the monitoring of a specific team and the adoption of progressive closure.

Open abdomen management: single institution experience / Abdômen aberto: experiência em uma única instituição

OBJECTIVE: To evaluate the outcome of abdominal wall integrity of both techniques. METHODS: a retrospective study was carried out at the Hospital das Clínicas, Faculdade de Medicina, Universidade de São Paulo, identifying the patients undergoing temporary abdominal closure (TAC) from January 2005 to December 2011. Data were collected through the review of clinical charts. Inclusion criteria were indication of TAC and survival to definitive abdominal closure. In the post-operative period only a group of three surgeons followed all patients and performed the reoperations. RESULTS: Twenty eightpatients were included. The difference in primary closure rates and mean time for fascial closure did not reach statistical significance (p=0.98 and p=0.23, respectively). CONCLUSION: VAC and Bogota Bag do not differ significantly regarding the outcome of abdominal wall integrity, due to the monitoring of a specific team and the adoption of progressive closure.

OBJETIVO: Avaliar o resultado da integridade da parede abdominal após utilização do fechamento assistido a vácuo e da bolsa de Bogotá. MÉTODOS: um estudo retrospectivo foi realizado no Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo (HCFMUSP), identificando os pacientes submetidos à técnica de fechamento abdominal temporário (FAT) entre janeiro de 2005 e dezembro de 2011. Os dados foram coletados por meio de revisão de prontuários. Os critérios de inclusão foram indicação de FAT e sobrevivência até o fechamento definitivo da parede abdominal. No período pós-operatório, apenas um grupo de três cirurgiões, seguiu todos os pacientes e realizou as reoperações. Além disso, independente da técnica de FAT utilizada, foi aplicada a tática de fechamento fascial progressivo durante as reoperações. RESULTADOS: Vinte e oito pacientes foram incluídos. Não houve diferença estatística nas taxas de fechamento primário e tempo médio de fechamento fascial. CONCLUSÃO: O fechamento assistido a vácuo e a bolsa de Bogotá não diferem significativamente em relação ao resultado da integridade da parede abdominal após as reoperações. Isso se deve ao acompanhamento de uma equipe específica e a adoção de técnica de fechamento fascial progressivo.

Out-of-equilibrium dynamics of photoexcited spin-state concentration waves.

The spin crossover compound [FeIIH2L2-Me][PF6]2 presents a two-step phase transition. In the intermediate phase, a spin state concentration wave (SSCW) appears resulting from a symmetry breaking (cell doubling) associated with a long-range order of alternating high and low spin molecular states. By combining time-resolved optical and X-ray diffraction measurements on a single crystal, we study how such a system responds to femtosecond laser excitation and we follow in real time the erasing and rewriting of the SSCW.