Face, content, and construct validity of human placenta as a haptic training tool in neurointerventional surgery.

OBJECT The development of neurointerventional treatments of central nervous system disorders has resulted in the need for adequate training environments for novice interventionalists. Virtual simulators offer anatomical definition but lack adequate tactile feedback. Animal models, which provide more lifelike training, require an appropriate infrastructure base. The authors describe a training model for neurointerventional procedures using the human placenta (HP), which affords haptic training with significantly fewer resource requirements, and discuss its validation. METHODS Twelve HPs were prepared for simulated endovascular procedures. Training exercises performed by interventional neuroradiologists and novice fellows were placental angiography, stent placement, aneurysm coiling, and intravascular liquid embolic agent injection. RESULTS The endovascular training exercises proposed can be easily reproduced in the HP. Face, content, and construct validity were assessed by 6 neurointerventional radiologists and 6 novice fellows in interventional radiology. CONCLUSIONS The use of HP provides an inexpensive training model for the training of neurointerventionalists. Preliminary validation results show that this simulation model has face and content validity and has demonstrated construct validity for the interventions assessed in this study.

Face, Content, and Construct Validity of Brain Tumor Microsurgery Simulation Using a Human Placenta Model.

BACKGROUND: Brain tumors are complex 3-dimensional lesions. Their resection involves training and the use of the multiple microsurgical techniques available for removal. Simulation models, with haptic and visual realism, may be useful for improving the bimanual technical skills of neurosurgical residents and neurosurgeons, potentially decreasing surgical errors and thus improving patient outcomes. OBJECTIVE: To describe and assess an ex vivo placental model for brain tumor microsurgery using a simulation tool in neurosurgical psychomotor teaching and assessment. METHODS: Sixteen human placentas were used in this research project. Intravascular blood remnants were removed by continuous saline solution irrigation of the 2 placental arteries and placental vein. Brain tumors were simulated using silicone injections in the placental stroma. Eight neurosurgeons and 8 neurosurgical residents carried out the resection of simulated tumors using the same surgical instruments and bimanual microsurgical techniques used to perform human brain tumor operations. Face and content validity was assessed using a subjective evaluation based on a 5-point Likert scale. Construct validity was assessed by analyzing the surgical performance of the neurosurgeon and resident groups. RESULTS: The placenta model simulated brain tumor surgical procedures with high fidelity. Results showed face and content validity. Construct validity was demonstrated by statistically different surgical performances among the evaluated groups. CONCLUSION: Human placentas are useful haptic models to simulate brain tumor microsurgical removal. Results using this model demonstrate face, content, and construct validity.

Enterobacteriaceae resistant to third generation cephalosporins upon hospital admission: risk factors and clinical outcomes

Objectives: Evaluate risk factors and clinical outcomes of infections caused by Enterobacteriaceae resistant to third-generation cephalosporins present in samples collected upon hospital admission. Methods: Risk factors were evaluated using a 1:2 ratio case-control study. Influence of resistance on the appropriateness of antibiotic therapy, length of stay, and hospital mortality were prospectively evaluated. Characteristics independently associated with the presence of resistant enterobacteria were assessed by logistic regression. Results: Enterobacteria resistant to third-generation cephalosporins were quite common (26.0%). Male gender (OR: 2.66; 95% CI, 1.17-5.06; p = 0.019), invasive prosthesis (OR: 3.79; 95% CI, 1.29-11.08; p = 0.015), previous use of cephalosporins (OR: 2.77; 95% CI, 1.10-6.97; p = 0.029) and hospitalization in the last 6 months (OR: 5.33; 95% CI, 2.29-12.44; p < 0.001) were independently associated with the presence of these microorganisms. These bacteria were associated with higher frequency of inappropriate antimicrobial therapy, worse clinical response, and longer length of stay. Finally, older age, admission to the ICU, and site of infection other than urinary tract were independently associated to higher hospital mortality. Conclusions: Risk factors identified in this study may help in the choice of empirical antibiotic therapy for infected patients suspected of harboring these bacteria and in the early implementation of measures to avoid the spread of these bacteria in the hospital environment. .

Enterobacteriaceae resistant to third generation cephalosporins upon hospital admission: risk factors and clinical outcomes.

OBJECTIVES: Evaluate risk factors and clinical outcomes of infections caused by Enterobacteriaceae resistant to third-generation cephalosporins present in samples collected upon hospital admission. METHODS: Risk factors were evaluated using a 1:2 ratio case-control study. Influence of resistance on the appropriateness of antibiotic therapy, length of stay, and hospital mortality were prospectively evaluated. Characteristics independently associated with the presence of resistant enterobacteria were assessed by logistic regression. RESULTS: Enterobacteria resistant to third-generation cephalosporins were quite common (26.0%). Male gender (OR: 2.66; 95% CI, 1.17-5.06; p=0.019), invasive prosthesis (OR: 3.79; 95% CI, 1.29-11.08; p=0.015), previous use of cephalosporins (OR: 2.77; 95% CI, 1.10-6.97; p=0.029) and hospitalization in the last 6 months (OR: 5.33; 95% CI, 2.29-12.44; p<0.001) were independently associated with the presence of these microorganisms. These bacteria were associated with higher frequency of inappropriate antimicrobial therapy, worse clinical response, and longer length of stay. Finally, older age, admission to the ICU, and site of infection other than urinary tract were independently associated to higher hospital mortality. CONCLUSIONS: Risk factors identified in this study may help in the choice of empirical antibiotic therapy for infected patients suspected of harboring these bacteria and in the early implementation of measures to avoid the spread of these bacteria in the hospital environment.

Human placenta aneurysm model for training neurosurgeons in vascular microsurgery.

BACKGROUND: Neurosurgery, a demanding specialty, involves many microsurgical procedures that require complex skills, including open surgical treatment of intracranial aneurysms. Simulation or practice models may be useful for acquiring these skills before trainees perform surgery on human patients. OBJECTIVE: To describe a human placenta model for the creation and clipping of aneurysms. METHODS: Placental vessels from 40 human placentas that were dimensionally comparable to the sizes of appropriate cerebral vessels were isolated to create aneurysms of different shapes. The placentas were then prepared for vascular microsurgery exercises. Sylvian fissure--like dissection technique and clipping of large- and small-necked aneurysms were practiced on human placentas with and without pulsatile flow. A surgical field designed to resemble a real craniotomy was reproduced in the model. RESULTS: The human placenta has a plethora of vessels that are of the proper dimensions to allow the creation of aneurysms with dome and neck dimensions similar to those of human saccular and fusiform cerebral aneurysms. These anatomic scenarios allowed aneurysm inspection, manipulation, and clipping practice. Technical microsurgical procedures include simulation of sylvian fissure dissection, unruptured aneurysm clipping, ruptured aneurysm clipping, and wrapping; all were reproduced with high fidelity to the haptics of live human surgery. Skill-training exercises realistically reproduced aneurysm clipping. CONCLUSION: Human placenta provides an inexpensive, widely available, convenient biological tissue that can be used to create models of cerebral aneurysms of different morphologies. Neurosurgical trainees may benefit from the preoperative use of a realistic model to gain familiarity and practice with critical surgical techniques for treating aneurysms.

A atenção primária à saúde no município de Ouro Preto ? MG: relato baseado na experiência do internato de saúde coletiva / Primary health care in Ouro Preto, Minas Gerais, Brazil: a report based on the experience of collective health internship

O Sistema Único de Saúde (SUS) no Brasil, criado na Constituição Federal de 1988, enuncia todos os conceitos e medidas práticas de Estado para promover, proteger e recuperar a saúde humana no território nacional. A principal porta de entrada para o SUS se constitui das Unidades de Atenção Primária à Saúde (APS), que são capazes de identificar os fatores potencialmente danosos à saúde e atuar no sentido de seu equacionamento e resolução. Adicionalmente, lhes compete cuidar das demandas clínicas, seja no nível primário da atenção, seja por encaminhamento e recebimento posterior de contrarreferência dos casosque necessitam de mais incorporação tecnológica e de avaliação por especialistas. Este artigo apresenta a experiência na APS a partir da vivência discente supervisionada durante o Internato de Saúde Coletiva (?Internato Rural?) realizado ao longo do quarto trimestre de 2011, no município de Ouro Preto, Minas Gerais. Intenciona também promover reflexões acerca do conteúdo teórico de sua constituição e da realidade de sua prática.

The Brazilian Unified Health System (SUS), created in 1988 Federal Constitution, enunciates all State concepts and practical measures to promote, protect, and recover human health in the national territory. The main entrance door for the SUS is made of Health Primary Care Units (APS), which are able to identify the potentially damaging factors tohealth, and to act as its guidance and resolution. In addition, they are in charge of taking care of clinical demands, be them in care primary level, be for following and posterior reception of counter-reference cases that need more technological incorporation and evaluation by experts. This article represents the experience at the APS from a supervised schoolvisit during the Collective Health Internship (?Rural Internship?) carried out throughout 2011 fourth trimester, in Ouro Preto, Minas Gerais, Brazil. It also intends to promote reflections about the theoretical content of its constitution and its practice reality.