Medicosurgical management of deep wound infections after thoracolumbar instrumentation: risk factors of poor outcomes.

BACKGROUND: Surgical site infection (SSI) after thoracolumbar osteosynthesis is a common complication. Its management relies on surgical revision and antibiotic therapy, but treatment failure is not uncommon. The aim of our study was to assess the frequency of SSI management failure and its risk factors. METHODS: A retrospective study of patients hospitalized from 2011 to 2019 at the University Hospital of Caen was carried out. The infection rate and the time to onset of failure were assessed over a minimum follow-up of 1 year. Treatment failure was defined as the occurrence of a new intervention in the spine in the year following the end of antibiotic therapy, the establishment of long-term suppressive antibiotic therapy, or death from any cause within 1 year of the end of antibiotic therapy. We compared the treatment failure group with the treatment success group to determine risk factors for treatment failure. RESULTS: A total of 2881 patients underwent surgery during the study period, and 92 developed an SSI, corresponding to an SSI rate of 3.19%. Thirty-six percent of the patients with an SSI presented treatment failure. The median time to failure was 31 days. On multivariate analysis, diabetes mellitus was identified as a risk factor for treatment failure, whereas prolonged postoperative drainage for 4 to 5 days was a protective factor. CONCLUSIONS: The number of failures was significant, and failure occurred mainly during the early phase. To decrease the risk of treatment failure, prolonged duration of postoperative drainage seems to be helpful. Additionally, as diabetes is a risk factor for treatment failure, good control of glycemia in these patients might impact their outcomes.

Patient-centeredness to anticipate and organize an end-of-life project for patients receiving at-home palliative care: a phenomenological study.

BACKGROUND: The development of end-of-life primary care is a socio-medical and ethical challenge. However, general practitioners (GPs) face many difficulties when initiating appropriate discussion on proactive shared palliative care. Anticipating palliative care is increasingly important given the ageing population and is an aim shared by many countries. We aimed to examine how French GPs approached and provided at-home palliative care. We inquired about their strategy for delivering care, and the skills and resources they used to devise new care strategies. METHODS: Twenty-one GPs from the South of France recruited by phone according to their various experiences of palliative care agreed to participate. Semi-structured interview transcripts were examined using a phenomenological approach inspired by Grounded theory, and further studied with semiopragmatic analysis. RESULTS: Offering palliative care was perceived by GPs as a moral obligation. They felt vindicated in a process rooted in the paradigm values of their profession. This study results in two key findings: firstly, their patient-centred approach facilitated the anticipatory discussions of any potential event or intervention, which the GPs openly discussed with patients and their relatives; secondly, this approach contributed to build an "end-of-life project" meeting patients' wishes and needs. The GPs all shared the idea that the end-of-life process required human presence and recommended that at-home care be coordinated and shared by multi-professional referring teams. CONCLUSIONS: The main tenets of palliative care as provided by GPs are a patient-centred approach in the anticipatory discussion of potential events, personalized follow-up with referring multi-professional teams, and the collaborative design of an end-of-life project meeting the aspirations of the patient and his or her family. Consequently, coordination strategies involving specialized teams, GPs and families should be modelled according to the specificities of each care system.

Short isthmic versus long trans-isthmic C2 screw: anatomical and biomechanical evaluation.

INTRODUCTION: The Harms technique is now considered as the gold standard to stabilize C1-C2 cervical spine. It has been reported to decrease the risk of vertebral artery injury. However, the risk of vascular injury does not totally disappear, particularly due to the proximity of the trans-isthmic C2 screw with the foramen transversarium of C2. In order to decrease this risk of vertebral artery injury, it has been proposed to use a shorter screw which stops before the foramen transversarium. OBJECT: The main objective was to compare the pull-out strength of long trans-isthmic screw (LS) versus short isthmic screw (SS) C2 screw. An additional morphological study was also performed. METHOD: Thirteen fresh-frozen human cadaveric cervical spines were included in the study. Orientation, width and height of the isthmus of C2 were measured on CT scan. Then, 3.5-mm titanium screws were inserted in C2 isthmus according to the Harms technique. Each specimen received a LS and a SS. The side and the order of placement were determined with a randomization table. Pull-out strengths and stiffness were evaluated with a testing machine, and paired samples were compared using Wilcoxon signed-rank test and also the Kaplan-Meier method. RESULTS: The mean isthmus transversal orientation was 20° ± 6°. The mean width of C2 isthmus was less than 3.5 mm in 35 % of the cases. The mean pull-out strength for LS was 340 ± 85 versus 213 ± 104 N for SS (p = 0.004). The mean stiffness for the LS was 144 ± 40 and 97 ± 54 N/mm for the SS (p = 0.02). DISCUSSION: The pull-out strength of trans-isthmic C2 screws was significantly higher (60 % additional pull-out resistance) than SSs. Although associated with an inferior resistance, SSs may be used in case of narrow isthmus which contraindicates 3.5-mm screw insertion but does not represent the first option for C2 instrumentation. LEVEL OF EVIDENCE: Level V.

Influence of Obesity on Access-Related Complications During Anterior Lumbar Spine Interbody Fusion.

OBJECTIVE: The anterior lumbar spine approach has gained in popularity in recent years, but the associated access-related complications for obese patients have not been clearly established. This study aimed to analyze the relationship between obesity or overweight and the safety of the anterior lumbar spine approach. METHODS: Eighty-four consecutive patients admitted for lumbar spine surgery by anterior approach between 2011 and 2014 were included. The surgical approach consisted of left lateral minilaparotomy and retroperitoneal dissection. The patients were categorized into 3 different groups according to their body mass index (BMI). The studied outcomes measures included medical history, BMI, the number of fused levels, surgery duration, blood loss, vascular injury, day of discharge, surgical revision, and wound infection. RESULTS: No significant difference was found across the BMI groups with regard to vascular or infectious complications. The duration of surgery was significantly higher in the obese group. CONCLUSIONS: Because BMI does not seem to increase the overall risk of complications, the anterior lumbar spine approach should be considered in obese or overweight patients, as in nonoverweight patients.

Flavor preference conditioning as a function of fat source.

Rats learn to prefer foods based, in part, on postingestive nutrient actions. This study compared the effectiveness of intragastric (IG) infusions of fat emulsions which varied in their fatty acid composition (chain length and saturation) to condition preferences for flavored saccharin solutions. In Experiment 1, food-restricted rats were trained (30 min/day) with one flavor (CS+CO) paired with IG corn oil (CO) and a second flavor (CS+MCT) paired with IG medium chain triglyceride (MCT); the fats were prepared as isocaloric emulsions. A third flavor (CS-) was paired with IG water. The rats subsequently showed a strong preference for the CS+CO (84%) and a weaker preference for the CS+MCT (65%) relative to the CS-. In a direct choice test, the CS+CO was preferred to the CS+MCT by 75%. In Experiment 2, new rats trained with flavors paired with IG corn oil and beef tallow (BT) infusions learned to prefer both the CS+CO (89%) and the CS+BT (82%) relative to the CS-, and preferred the CS+CO to the CS+BT by 67%. The same rats were trained with three new flavors paired with IG infusions of corn oil, vegetable shortening (VS), and water. The rats strongly preferred both the CS+CO (91%) and CS+VS (86%) over the CS-, and they preferred the CS+CO to the CS+VS by 64%. In Experiment 3, new rats trained with corn oil and safflower oil (SO) paired flavors preferred both the CS+CO and CS+SO to the CS-, and equally preferred the CS+CO and CS+SO in two-bottle tests. The rats were also given one-and two-bottle tests with the various fat emulsions and their preference profile was consistent with their conditioned preferences for the flavored saccharin solutions. These findings demonstrate that many different fat sources can condition flavor preferences. Fats with high polyunsaturated content and/or lower saturated fat content are the most reinforcing.

Effects of exogenous ammonia or free amino acids on proteolytic activity and protein breakdown products in Streptococcus bovis, Prevotella albensis, and Butyrivibrio fibrisolvens.

We studied in details the ammonia or free amino acids (AA) effects on proteolytic activity of three ruminal bacteria: enzymatic activities and protein breakdown products were measured at the end of the exponential growth phase. In Streptococcus bovis the simultaneous uptake of ammonia and probably small peptides induced a decline in total proteolytic activity as a result of changes in endopeptidasic activities. With free AA, the tendency for the endopeptidasic activities to specialise was more evident and the total proteolytic activity decreased too. In Prevotella albensis, the inhibition of proteolysis with free AA was linked to the disappearance of free endopeptidases, to the specialization of cell-associated endopeptidases and to the decrease in exopeptidases. The decrease of proteolysis in P. albensis when ammonia was added was more difficult to interpret. With ammonia or AA Butyrivibro fibrisolvens developed a distinct behavior of those expressed by the other species: the increase of the total proteolytic activity could be explained by a better balance of the endopeptidases expressed. It then clearly appeared that the expression of the proteolytic activities are linked to the nature and/or to the quantity of the nitrogen source. This leads each species to adopt its own nutritional strategy in order to adapt to the environmental conditions of the ruminal ecosystem.