The speciation and genotyping of Cronobacter isolates from hospitalised patients

The World Health Organization (WHO) has recognised all Cronobacter species as human pathogens. Among premature neonates and immunocompromised infants, these infections can be life-threatening, with clinical presentations of septicaemia, meningitis and necrotising enterocolitis. The neurological sequelae can be permanent and the mortality rate as high as 40-80%. Despite the highlighted issues of neonatal infections, the majority of Cronobacter infections are in the elderly population suffering from serious underlying disease or malignancy and include wound and urinary tract infections, osteomyelitis, bacteraemia and septicaemia. However, no age profiling studies have speciated or genotyped the Cronobacter isolates. A clinical collection of 51 Cronobacter strains from two hospitals were speciated and genotyped using 7-loci multilocus sequence typing (MLST), rpoB gene sequence analysis, O-antigen typing and pulsed-field gel electrophoresis (PFGE). The isolates were predominated by C. sakazakii sequence type 4 (63%, 32/51) and C. malonaticus sequence type 7 (33%, 17/51). These had been isolated from throat and sputum samples of all age groups, as well as recal and faecal swabs. There was no apparent relatedness between the age of the patient and the Cronobacter species isolated. Despite the high clonality of Cronobacter, PFGE profiles differentiated strains across the sequence types into 15 pulsotypes. There was almost complete agreement between O-antigen typing and rpoB gene sequence analysis and MLST profiling. This study shows the value of applying MLST to bacterial population studies with strains from two patient cohorts, combined with PFGE for further discrimination of strains.

[Refusal of care in the intensive care: how makes decision?]

OBJECTIVES

Decision-making bringing to an admission or not in intensive care is complex. The aim of this study is to analyze with an ethical point of view the making decision process leading to the refusal and its consequences. It is proposed a setting in prospect through the principles of beneficence, non-maleficience, respect for autonomy, justice, and the Leonetti law.

PATIENTS AND METHODS

Prospective study in surgical reanimation at the University Hospital of Rouen over 9 months (November 2007-September 2008). Systematic collection for each non-admitted patient of the general characters, the methods of decision making, immediate becoming and within 48 h Constitution of two groups: patients for whom an admission in intensive care could be an unreasonable situation of obstinacy, and patients for whom an admission in reanimation would not be about unreasonable if it occurred.

RESULTS

One hundred and fifty situations were analyzed. The potentially unreasonable character of an admission does not involve necessarily a refusal of care in intensive care. The question of the lack of place and equity in the access to the care is real but relative according to the typology of the patients. The research of the respect of the autonomy of the patient is difficult but could be facilitated. The Leonetti law does not appear to be able to be a framework with the situation of refusal of care in intensive care.

CONCLUSION

It is not a question of going towards a systematic admission in intensive care of any patient proposed, but to make sure that so if there is a refusal, it is carried out according to a step ethically acceptable.

Evaluation of a surgical simulator for learning clinical anatomy

BACKGROUND

New techniques in imaging and surgery have made 3-dimensional anatomical knowledge an increasingly important goal of medical education. This study compared the efficacy of 2 supplemental, self-study methods for learning shoulder joint anatomy to determine which method provides for greater transfer of learning to the clinical setting.

METHODS

Two groups of medical students studied shoulder joint anatomy using either a second-generation virtual reality surgical simulator or images from a textbook. They were then asked to identify anatomical structures of the shoulder joint as they appeared in a videotape of a live arthroscopic procedure.

RESULTS

The mean identification scores, out of a possible score of 7, were 3.1 +/- 1.3 for the simulator group and 2.9 +/- 1.5 for the textbook group (P = 0.70). Student ratings of the 2 methods on a 5-point Likert scale were significantly different. The simulator group rated the simulator more highly as an effective learning tool than the textbook group rated the textbook (means of 3.2 +/- 0.7 and 2.6 +/- 0.5, respectively, P = 0.02). Furthermore, the simulator group indicated that they were more likely to use the simulator as a learning tool if it were available to them than the textbook group was willing to use the textbook (means of 4.0 +/- 1.2 and 3.0 +/- 0.9, respectively, P = 0.02).

CONCLUSION

Our results show that this surgical simulator is at least as effective as textbook images for learning anatomy and could enhance student learning through increased motivation. These findings provide insight into simulator development and strategies for learning anatomy. Possible explanations and future research directions are discussed.

Clinical fluoroscopic fiducial-based registration of the vertebral body in spinal neuronavigation

We present a system involving a computer-instrumented fluoroscope for the purpose of 3D navigation and guidance using pre-operative diagnostic scans as a reference. The goal of the project is to devise a computer-assisted tool that will improve the accuracy, reduce risk, minimize the invasiveness, and shorten the time it takes to perform a variety of neurosurgical and orthopedic procedures of the spine. For this purpose we propose an apparatus that will track surgical tools and localize them with respect to the patient's 3D anatomy and pre-operative 3D diagnostic scans using intraoperative fluoroscopy for in situ registration and embedded fiducials. Preliminary studies have found a fiducial registration error (FRE) of 1.41 mm and a Target Localization Error (TLE) of 0.48 mm. The resulting system leverages equipment already commonly available in the operating room (OR), providing an important new functionality that is free of many current limitations, while keeping costs contained.

Neuronavigational epilepsy focus mapping

The localization of a seizure focus for resective surgery often requires invasive monitoring for precise localization of the target as well as structures to avoid. We report on the use of intra-operative surgical navigation to precisely localize and co-register subdural electrodes to regions of know radiographic pathology. Additionally, the navigation system was used to develop intra-operative electrode maps. These maps were subsequently used in the sub-acute recording phase to assign electrographic pathology and function (e.g. speech) to a specific cortical surface anatomy. This permitted for more precise planning of surgery and better assessment of potential risk, based on functional as well as anatomical criterion.

A comparative statistical analysis of neuronavigation systems in a clinical setting

The use of neuronavigation (NN) in neurosurgery has become ubiquitous. A growing number of neurosurgeons are utilizing NN for a wide variety of purposes, including optimizing the surgical approach (macrosurgery) and locating small areas of interest (microsurgery). The goal of our team is to apply rapid advances in hardware and software technology to the field of NN, challenging and ultimately updating current NN assumptions. To identify possible areas in which new technology may improve the surgical applications of NN, we have assessed the accuracy of neuronavigational measurements in the Radionics and BrainLab systems. Using a phantom skull, we measured how accurate the visualization of a navigational probe's tip was in these systems, taking a total of 2180 measurements. We found that, despite current NN tenets, error is maximal at the six marker count and minimal in the spreaded marker setting; that is, placing less markers around the area of interest maximizes accuracy and active tracking does not necessarily increase accuracy. Comparing the two systems, we also found that accuracy of NN machines differs both overall and in different axes. As researchers continue to apply technological advances to the NN field, an increasing number of currently held tenets will be revised, making NN an even more useful tool in neurosurgery.

Quantification of the gravity-dependent change in the C-arm image center for image compensation in fluoroscopic spinal neuronavigation

In the quest to develop a viable, frameless spinal navigation system, many researchers are utilizing the C-arm fluoroscope. However, there is a significant problem with the C-arm that must be quantified: the gravity-dependent sag effect resulting from the geometry of the C-arm and aggravated by the inequity of weight at each end of the C-arm. This study quantified the C-arm sag effect, giving researchers the protocol and data needed to develop a program that accounts for this distortion. The development of spinal navigation algorithms that account for the C-arm sag effect should produce a more accurate spinal navigation system.

Aesthetic results of treatment of large alopecia with total scalp expansion

In the last 7 years, 18 patients with large alopecia (approximately one-third of hair-bearing scalp) were treated with 31 tissue expansion procedures. In the previous 44 patients, with various degrees of alopecia treated with conventional tissue expansion technique, the major complication rates were as high as reported in the relevant literature. The clinical experience gained with these cases led us to make some modifications in the surgical technique. We applied some simple surgical maneuvers and Z-plasties to the last 18 cases with large alopecia. The major complication rate of 3.2% observed in this study is comparable to the lower complication rates of 6-12% reported in the literature for different degrees of alopecia. We believe that these simple modifications and meticulous approach improve the results of conventional treatment of alopecia with tissue expansion and flap. In this paper, details of the insertion technique and reconstructive procedures and their relevance to the success rate of the aesthetic treatment of the large alopecia are discussed.

Preoperative sagittal CT evaluation of the frontal recess

Endoscopic surgical approaches for chronic frontal sinusitis require the reestablishment of adequate frontal sinus ventilation and drainage for relief of symptoms. After the resection of anterior ethmoid mucosal disease and cellular structure, the anterior to posterior depth of the nasofrontal beak to the base of skull at the insertion of the ethmoidal bulla (frontal sinus ostium) often represents a critical margin for functional success. However, little information concerning this dimension is available. Depending on intraoperative surgical judgment of this distance, extended endoscopic surgical procedures involving additional bone resection may be indicated. These approaches may be hazardous due to the proximity of the cranial cavity and orbit. In addition, secondary stenosis can result from the subsequent inflammatory response. Improved CT imaging, high resolution sagittal reformatting, and computer workstations provide the ability to obtain direct preoperative measurements of the frontal recess. We used a paramedian sagittal section and recorded the maximal anterior to posterior depth from the nasofrontal beak to the base of skull at the insertion of the ethmoidal bulla in 20 patients, 31 sides, undergoing primary endoscopic frontoethmoidectomy. In addition, we found a positive correlation between this distance and agger nasi air cell size measured in the same 31 sides.