Intraoperative ultrasound-assisted endoscopic treatment of primary intermediate and high-grade vesicoureteral reflux in children in a long-term follow-up.

BACKGROUND: Endoscopic treatment of vesicoureteral reflux (VUR) is an important minimally invasive surgical approach in patients undergoing surgical treatment of VUR. In our past experience, we observed that a bulking agent mound sagittal diameter of 10 mm is the main predictor of effectiveness of the procedure. Moreover we noticed that the use of intraoperative ultrasound, allows the surgeon to better identify the site, volume and shape of the bulking agent injected, finally reducing operative time. OBJECTIVE: We aimed to evaluate if the intraoperative ultrasound assistance could definitively improve effectiveness of the endoscopic procedure. METHODS: We retrospectively compared two series treated with endoscopic procedures for intermediate and high grade primary VUR, respectively without (series A) and with (series B) intraoperative ultrasound (IO-US). In all patients VCUG was performed to assess VUR grade and to verify resolution or VUR downgrading during the follow-up. RESULTS: A total of 177 ureteric units were treated. Endoscopic procedures globally were effective in 68/96 ureters (70.8 %) in series A and in 68/81 ureters (83.9 %) in series B. No significant differences in effectiveness were observed comparing the series with regard to VUR grades, but a significant difference is shown (p < 0.05) when grouping grades III-V VUR. No significance in differences of volume injected were detected, but operative time was significantly lower in series B (27.5 min vs 19.6 min, p < 0.05). Mean sagittal mound diameter measured during cystoscopy in series B was 10.45 mm (range 8.5-14.2 mm). DISCUSSION: The intraoperative ultrasound assistance during endoscopic treatment of VUR could represent a valid tool for surgeons to better identify location, volume and shape of the bulking agent. Furthermore, the use of an objective parameter of evaluation of the implant can overcome the subjective intraoperative evaluation of the implant itself, improving results for experienced surgeons and reducing the learning-curve for inexperienced ones. CONCLUSIONS: Results of endoscopic injection of bulking-agent can be improved with intraoperative ultrasound, allowing at the same time a significant reduction of operative time.

Penile Length Assessment of Children Treated for Primary Buried Penis: Can Satisfying Penile Growth Always Be Achieved?

Primary buried (BP) penis is describes as a small penis caused by a penile ligaments anomaly; it is unclear if a primary BP could reach a normal length. We selected 49 patients treated at our institution between 2015 and 2020 in order to post-operatively evaluate the SPL after one year. SPL was evaluated according to the PH Tanner staging system for pre-pubertal patients according to age-normalized values. A micropenis was detected if the SPL was below 2.5 SD. A normal SPL was found in thirty-two patients, eighteen were in PH Stage 1, four were in PH Stage 2, six were in PH Stage 3, and four were in PH Stage 5. Seventeen patients showed a reduced SPL; in seven of these (four in PH Stage 4 and three in PH Stage 5), their SPL was <2.5 ST. The difference in micropenis prevalence between the pre-pubertal and post-pubertal patients was significant (p = 0.038). A primary BP grows normally during the pre-pubertal period, where patients frequently showed a normal SPL, but it seems to be unable to reach a normal length in the higher PH stages, where the SPL is used to detect a micropenis. We suggest that a primary BP should be considered not as a simple defect of the penile ligaments and surrounding tissues, but as an incomplete manifestation of a micropenis due to a growth slowdown of the organ in late puberty.

Evaluation of Anal Sphincter with High Resolution Anorectal Manometry and 3D Reconstruction in Patients with Anorectal Malformation.

BACKGROUND: Patients with anorectal malformation (ARM) need long-term follow-up, in order to evaluate fecal continence; the main predictors of longer-term success are the type of ARM, associated anomalies and sacral integrity. Three-Dimensional High Resolution Anorectal Manometry (3D-HRAM) gives detailed information on pressure on the anal complex profile. Our objective was to analyze anal sphincter activity in ARM patients with 3D-HRAM establishing the correlation between manometric and clinical data. METHODS: Forty ARM patients were submitted to 3D-HRAM: manometric, anatomical and clinical scores were correlated with each other and with the bowel management response (BM). RESULTS: A positive correlation between all scores and types of ARM was found: in high ARM and in patients with spinal anomalies (regardless to ARM type) lower scores were reported and even after BM they did not achieve good continence. CONCLUSIONS: 3D-HRAM gives detailed data on the functional activity of the anal sphincter complex. Our study revealed a correlation between manometric parameters and clinical outcomes, confirming spinal malformations and ARM type as the most important prognostic risk factors for a bad outcome. Specific sphincteric defects can also be explored with manometry, allowing for tailored bowel management strategies.

Laparoscopic Assisted Percutaneous Anterior Gastropexy for the Management of Acute and Chronic Gastric Volvulus in Infants.

Acute and chronic gastric volvulus (ACGV) is a rare event in infants and children. Its prompt treatment is needed to avoid gastric ischemia and perforation. A laparotomy or a laparoscopic/endoscopic reduction with or without the gastrostomy formation has been described to treat this condition. We wanted to report our experience and describe the surgical technique used to perform the percutaneous laparoscopic assisted anterior gastropexy in neonates presenting with this condition. We perform a retrospective review of a single institution's experience with laparoscopic assisted percutaneous anterior gastropexy over a seven-year period (2015-2022). Procedures were performed under general anesthesia and the anterior gastropexy was performed using a modified extracorporeal knotting technique as described for the laparoscopic assisted repair of inguinal hernias via percutaneous internal ring suturing. Thirteen patients underwent surgery for ACGV at our institution over a seven-year period. The median age at diagnosis was 57 days, 7/13 patients presented with acute vomiting and regurgitation (54%), 1/13 (8%) presented with mainly feeding difficulties and 1/13 (8%) presented with acute abdominal distension. Data were not available for 4/13 patients. All of the patients underwent laparoscopic assisted anterior gastropexy using extracorporeal knotting technique; no gastrostomy insertion was needed. The median operative time was 50 min (40-95 min). No intraoperative complications were reported. Post-operatively patients were started on feeds on day 3 (2-5 days). Only one patient (8%) developed a postoperative complication: subcutaneous granuloma at the extracorporeal knot site. Although rare, acute GV is an important cause of gastric outlet obstruction with a detrimental outcome if not promptly recognized and treated. Laparoscopic assisted percutaneous anterior gastropexy is an attractive and safe alternative for the management of this condition in both infants and older children. This technique does not require gastrostomy placement and it has a very low morbidity rate with no mortality reported.

Quality of life improving after propranolol treatment in patients with Infantile Hemangiomas.

Infantile hemangiomas may affect the quality of life (QoL) of patients and their family members, as anxiety and worry may commonly occur in parents, also linked to the social adversion they experience. We underline the beneficial impact of oral propranolol therapy on QoL of patients with infantile hemangiomas (IH) and of their relatives. A specific questionnaire measuring QoL was administered to parents of IH patients at beginning and end of a treatment with oral propranolol. Different aspects were investigated: site of the lesion, age of patients at starting therapy, length of treatment, occurrence of adverse effects and persistence/recurrence of the vascular anomaly. In all cases the questionnaire revealed a significant improvement of QoL, which was independent from all analyzed factors. It showed that oral propranolol administration in these patients combines optimal clinical results with relevant improvement of QoL, especially in cases of early management. The improvement of QoL seems unrelated to site of lesion, timing and duration of therapy, occurrence of drug-related adverse effects and persistence/recurrence of disease.

Moral Distress in Healthcare Providers Who Take Care of Critical Pediatric Patients throughout Italy-Cultural Adaptation and Validation of the Italian Pediatric Instrument.

BACKGROUND: Although Moral Distress (MD) is a matter of concern within the Pediatric Intensive Care Unit (PICU), there is no validated Italian instrument for measuring the phenomenon in nurses and physicians who care for pediatric patients in Intensive Care. The authors of the Italian Moral Distress Scale-Revised (Italian MDS-R), validated for the adult setting, in 2017, invited further research to evaluate the generalizability of the scale to clinicians working in other fields. Our study aims to reduce this knowledge gap by developing and validating the pediatric version of the Italian MDS-R. METHODS: We evaluated the new instrument for construct validity, then we administered it in a multicenter, web-based survey that involved healthcare providers of three PICUs and three adult ICUs admitting children in northern, central, and southern Italy. Finally, we tested it for internal consistency, confirmatory factorial validity, convergent validity, and differences between groups analysis. RESULTS: The 14-item, three-factor model best fit the data. The scale showed good reliability (a = 0.87). Still, it did not correlate with the Emotional Exhaustion and Depersonalization sub-scales of the Maslach Burnout Inventory (MBI) or with the 2-item Connor-Davidson Resilience Scale (CD-RISC 2) or the Satisfaction with Life Scale (SWLS). A mild correlation was found between the Italian Pediatric MDS-R score and intention to resign from the job. No correlation was found between MD and years of experience. Females, nurses, and clinicians who cared for COVID-19 patients had a higher MD score. CONCLUSIONS: The Italian Pediatric MDS-R is a valid and reliable instrument for measuring MD among Italian health workers who care for critically ill children. Further research would be helpful in better investigating its applicability to the heterogeneous scenario of Italian Pediatric Critical Care Medicine.

Double level knee osteotomy using patient-specific cutting guides is accurate and provides satisfactory clinical results: a prospective analysis of a cohort of twenty-two continuous patients.

PURPOSE: Double level osteotomy (DLO) (femoral and tibial) is a technically demanding procedure for which pre-operative planning accuracy and intraoperative correction are key factors. The aim of this study was to assess the accuracy of the achieved correction using patient-specific cutting guides (PSCGs) compared to the planned correction, its ability to maintain joint line obliquity (JLO), and to evaluate clinical outcomes and level of patient satisfaction at a follow-up of two years. METHODS: A single-centre, prospective observational study including 22 patients who underwent DLO by PSCGs between 2014 and 2018 was performed. Post-operative alignment was evaluated and compared with the target angular values to define the accuracy of the correction for the hip-knee-ankle angle (ΔHKA), medial proximal tibial angle (ΔMPTA), lateral distal femoral angle (ΔLDFA), and posterior proximal tibial angle (ΔPPTA). Pre- and post-operative JLO was also evaluated. At two year follow-up, changes in the KOOS sub-scores and patient satisfaction were recorded. The Mann-Whitney U test with 95% confidence interval (95% CI) was used to evaluate the differences between two variables; the paired Student's t test was used to estimate evolution of functional outcomes. RESULTS: The mean ΔHKA was 1.3 ± 0.5°; the mean ΔMPTA was 0.98 ± 0.3°; the mean ΔLDFA was 0.94 ± 0.2°; ΔPPTA was 0.45 ± 0.4°. The orientation of the joint line was preserved with a mean difference in the JLO of 0.4 ± 0.2. At last follow-up, it was recorded a significant improvement in all KOOS scores, and 19 patients were enthusiastic, two satisfied, and one moderately satisfied. CONCLUSION: Performing a DLO using PSCGs produces an accurate correction, without modification of the joint line orientation and with good functional outcomes at two year follow-up.

Osteotomy around the knee is planned toward an anatomical bone correction in less than half of patients.

INTRODUCTION: In cases where the femur or tibial deformity is not correctly analysed, the corrective osteotomies may result in an oblique joint line. The aim of this study was to assess the preoperative deformity of patients due to undergo corrective osteotomy and the resulting abnormal tibial and femoral morphologies after the planned correction using 3D software. METHODS: CT scans of 327 patients undergoing corrective osteotomy were retrospectively included. Each patient was planned using a software application and the simulated correction was validated by the surgeon. Following the virtual osteotomy, tibial and femoral coronal angular values were considered abnormal if the values were outside 97.5% confidence intervals for non-osteoarthritis knees. After virtual osteotomy, morphological abnormalities were split into two types. Type 1 was an under/overcorrection at the site of the osteotomy resulting in abnormal bone morphology. A type 2 was defined as an error in the site of the correction, resulting in an uncorrected abnormal bone morphology. RESULTS: The global rate of planned abnormalities after tibial virtual osteotomy was 50.7% (166/327) with abnormalities type 1 in 44% and type 2 in 6.7%. After femoral virtual osteotomy the global rate was 6.7% (22/327) with only abnormalities type 1. A lower preoperative HKA was significantly associated with a non-anatomical correction (R2=0.12, p<0.001) for both femoral (R2=0.06, p<0.001) and tibial (R2=0.07, p<0.001) abnormalities. CONCLUSION: Non-anatomical correction was found in more than half the cases analysed more frequently for preoperative global varus alignment. These results suggest that surgeons should considered anatomical angular values to avoid joint line obliquity. LEVEL OF EVIDENCE: III; retrospective cohort study.

Clinically Differentiated Abnormalities of the Architecture and Expression of Myosin Isoforms of the Human Cremaster Muscle in Cryptorchidism and Retractile Testis.

AIM: To describe architecture and expression of myosin isoforms of the human cremaster muscle (CM) and to individuate changes in clinically differentiated abnormalities of testicular descent: cryptorchidism or undescended testis (UDT) and retractile testis (RT). BACKGROUND: The CM is a nonsomitic striated muscle differentiating from mesenchyme of the gubernaculum testis. Morphofunctional and molecular peculiarities linked to its unique embryological origin are not yet completely defined. Its role in abnormalities of testicular descent is being investigated. SUBJECTS AND METHODS: Biopsy samples were obtained from corrective surgery in cases of cryptorchidism, retractile testis, inguinal hernia, or hydrocele. Muscle specimens were processed for morphology, histochemistry, and immunohistology. RESULTS AND CONCLUSIONS: The CM differs from the skeletal muscles both for morphological and molecular characteristics. The presence of fascicles with different characterization and its myosinic pattern suggested that the CM could be included in the specialized muscle groups, such as the extrinsic ocular muscles (EOMs) and laryngeal and masticatory muscles. The embryological origin from the nonsomitic mesoderm is, also for the CM, the basis of distinct molecular pathways. In UDT, the histological alterations of CM are suggestive of denervation; the genitofemoral nerve and its molecular messengers directed to this muscle are likely defective. Compared with the other samples, RT has a distinct myosinic pattern; therefore, it has been considered a well-defined entity with respect to the other testicular descent abnormalities.

Accuracy of magnetic resonance imaging to identify pseudocapsule invasion in renal tumors.

PURPOSE: To evaluate accuracy of MRI in detecting renal tumor pseudocapsule (PC) invasion and to propose a classification based on imaging of PC status in patients with renal cell carcinoma. METHODS: From January 2017 to June 2018, 58 consecutive patients with localized renal cell carcinoma were prospectively enrolled. MRI was performed preoperatively and PC was classified, according to its features, as follows: MRI-Cap 0 (absence of PC), MRI-Cap 1 (presence of a clearly identifiable PC), MRI-Cap 2 (focally interrupted PC), and MRI-Cap 3 (clearly interrupted and infiltrated PC). A 3D image reconstruction showing MRI-Cap score was provided to both surgeon and pathologist to obtain complete preoperative evaluation and to compare imaging and pathology reports. All patients underwent laparoscopic partial nephrectomy. In surgical specimens, PC was classified according to the renal tumor capsule invasion scoring system (i-Cap). RESULTS: A concordance between MRI-Cap and i-Cap was found in 50/58 (86%) cases. ρ coefficient for each MRI-cap and iCap categories was: MRI-Cap 0: 0.89 (p < 0.0001), MRI-Cap1: 0.75 (p < 0.0001), MRI-Cap 2: 0.76 (p < 0.0001), and MRI-Cap3: 0.87 (p < 0.0001). Sensitivity, specificity, positive predictive value, negative predictive value, and AUC were: MRI-Cap 0: Se 97.87% Spec 83.3%, PPV 95.8%, NPV 90.9%, and AUC 90.9; MRI-Cap 1: Se 77% Spec 95.5%, PPV 83.3%, NPV 93.5%, and AUC 0.86; MRI-Cap 2- iCap 2: Se 88% Spec 90%, PPV 79%, NPV 95%, and AUC 0.89; MRI-Cap 3: Se 94% Spec 95%, PPV 88%, NPV 97%, and AUC 0.94. CONCLUSIONS: MRI-Cap classification is accurate in evaluating renal tumor PC features. PC features can provide an imaging-guided landmark to figure out where a minimal margin could be preferable during nephron-sparing surgery.

Lattice Boltzmann method for miscible gases: A forcing-term approach.

A lattice Boltzmann method for miscible gases is presented. In this model, the standard lattice Boltzmann method is employed for each species composing the mixture. Diffusion interaction among species is taken into account by means of a force derived from kinetic theory of gases. Transport coefficients expressions are recovered from the kinetic theory. Species with dissimilar molar masses are simulated by also introducing a force. Finally, mixing dynamics is recovered as shown in different applications: an equimolar counterdiffusion case, Loschmidt's tube experiment, and an opposed jets flow simulation. Since collision is not altered, the present method can easily be introduced in any other lattice Boltzmann algorithms.

Temperature monitoring and lesion volume estimation during double-applicator laser-induced thermotherapy in ex vivo swine pancreas: a preliminary study.

Tissue temperature distribution plays a crucial role in the outcome of laser-induced thermotherapy (LITT), a technique employed for neoplasias removal. Since recent studies proposed LITT for pancreatic tumors treatment, assessment of temperature and of its effects around the laser applicator could be useful to define optimal laser settings. The aims of this work are temperature monitoring and measurement of ablated tissue volume in an ex vivo porcine pancreas undergoing double-applicator LITT. A three-dimensional numerical model is implemented to predict temperature rise and volumes of ablated tissue in treated pancreas. Experiments are performed to validate the model, with two modalities: (1) 12-fiber Bragg grating sensors are adopted to monitor the heating and cooling during LITT at several distances from the applicators tip, and (2) 1.5-T MR imaging is used to estimate the ablated volume. Experimental data agree with theoretical ones: at 2 mm from both applicators tips, the maximum temperature increase is approximately 60 °C downward from the tips, while it increases of about 40 °C and 30 °C, respectively, at the level and upward from the tips. This behavior occurs also at other distances, proving that the tissue downward from the tip is mostly heated. Furthermore, the estimated volume with MRI agrees with theoretical one (i.d., 0.91 ± 0.09 vs. 0.95 cm(3)). The encouraging results indicate that the model could be a suitable tool to choose the optimal laser settings, in order to control the volume of ablated tissue.

Diffusion-weighted lesions after carotid artery stenting are associated with cognitive impairment.

The effect of carotid artery stenting (CAS) on cognitive function is still debated. Cerebral microembolism, detectable by post-procedural diffusion-weighted imaging (DWI) lesions, has been suggested to predispose to cognitive decline. Our study aimed at evaluating the effect of CAS on cognitive profile focusing on the potential role of cerebral microembolic lesions, taking into consideration the impact of factors potentially influencing cognitive status (demographic features, vascular risk profile, neuropsychological evaluation at baseline and magnetic resonance (MR) markers of brain structural damage). Thirty-seven patients with severe carotid artery stenosis were enrolled. Neurological assessment, neuropsychological evaluation and brain MR were performed the day before CAS (E0). Brain MR with DWI was repeated the day after CAS (E1), while neuropsychological evaluation was done after a 14-month median period (E2). Volumes of both white matter hyperintensities and whole brain were estimated at E0 on axial MR FLAIR and T1w-SE sequences, respectively. Unadjusted ANOVA analysis showed a significant CAS*DWI interaction for MMSE (F=7.154(32), p=.012). After adjusting for factors potentially influencing cognitive status CAS*DWI interaction was confirmed for MMSE (F=7.092(13), p=.020). Patients with DWI lesions showed a mean E2-E0 MMSE reduction of -3.1, while group without DWI lesions showed a mean E2-E0 MMSE of +1.1. Our study showed that peri-procedural brain microembolic load impacts negatively on cognitive functions, independently from the influence of patients-related variables.

Antenatally diagnosed congenital cystic adenomatoid malformations (CCAM): Research Review.

Prenatal identification of lung abnormalities has increased with prenatal surveillance. With the advent of improved antenatal imaging over the past ten years, the diagnosis, assessment and management of congenital cystic lung abnormalities have changed. These were once considered the exclusive domain of the surgeon, who had the authority to operate on all congenital cystic lung abnormalities regardless of size or clinical signs in order to avoid the risk of cancer and improve lung growth in even asymptomatic infants. Clinicians are reconsidering this approach in the light of the spontaneous improvement and possible resolution that occurs over months to years with many of these lesions, thinking about the opportunity to take a more conservative approach in many minimally symptomatic or asymptomatic infants in the early months of life. The risks of subsequent cancer are poorly understood and probably overstated. Many centers advocate surgery only in cases of symptomatic or significant lesions, although there is little consensus as to what constitutes a significant lesion.This article will review current knowledge (classification, pathogenesis, genetics, prenatal evaluation, clinical implications) on congenital cystic adenomatoid malformations (CCAM) and discuss management options for young children with these lung abnormalities.

Determination of stature from skeletal and skull measurements by CT scan evaluation.

The aim of this article is to find a correlation between height and femur/skull measurements through Computed Tomography (CT) scans and derive regression equations for total skeletal height estimation in the Caucasian population. We selected 200 Caucasian patients from March 2010 to July 2011 who had to perform a CT scan for cancer restaging. The mean age is 64.5 years. Both sexes are represented by the same number of persons. Patients have executed a total body CT scan with contrast; once scan accomplished, we measured height through a digital scales. We analyzed CT scans of each patient, obtaining multiplanar reconstruction in sagittal and coronal planes with 1mm of thickness, and we measured 10 diameters of skull and femur. Then we performed a single and a multiple regression analysis considering the three diameters that better correlated with height. The skeletal diameters with the highest correlation coefficients with stature were femur lengths, length of cranial base (Ba-N), and distance from the posterior extremity of the cranial base to the inferior point of the nasal bone (Ba-NB). Although both femur and skull are skeletal segments used for stature estimation, in our sample femur gave stronger correlation with height than skull. h=35.7+1.48·BaN+2.32·BaNB+2.53·FEM and h=3.06·FEM+72.6 are the formulae that provided the most accurate stature assessment using multiple and single regression analysis respectively.

Use of dynamic CT in acute respiratory distress syndrome (ARDS) with comparison of positive and negative pressure ventilation.

Negative pressure ventilation via an external device ('iron lung') has the potential to provide better oxygenation with reduced barotrauma in patients with ARDS. This study was designed to see if oxygenation differences between positive and negative ventilation could be explained by CT. Six anaesthetized rabbits had ARDS induced by repeated saline lavage. Rabbits were ventilated with positive pressure ventilation (PPV) and negative pressure ventilation (NPV) in turn. Dynamic CT images were acquired over the respiratory cycle. A computer-aided method was used to segment the lung and calculate the range of CT densities within each slice. Volumes of ventilated lung and atelectatic lung were measured over the respiratory cycle. NPV was associated with an increased percentage of ventilated lung and decreased percentage of atelectatic lung. The most significant differences in ventilation and atelectasis were seen at mid-inspiration and mid-expiration (ventilated lung NPV = 61%, ventilated lung PPV = 47%, p < 0.001; atelectatic lung NPV = 10%, atelectatic lung PPV 19%, p < 0.001). Aeration differences were not significant at end-inspiration. Dynamic CT can show differences in lung aeration between positive and negative ventilation in ARDS. These differences would not be appreciated if only static breath-hold CT was used.

Pancreatic intraductal papillary mucinous neoplasms: a paradigmatic case. A case report and review of the literature.

Pancreatic intraductal papillary mucinous neoplasms constitute an increasingly frequent clinical entity. The definition and clinical behaviour of these tumours are still a subject of debate. As a consequence, their clinical management is also presents controversial aspects ranging from follow-up to the advisability or otherwise of an aggressive surgical approach, even in the case of small non-malignant lesions. In 2002 we observed a patient affected by a large pancreatic mass with the endoscopic and radiological features of an intraductal papillary mucinous tumour. Over a 20-year clinical history the patient had been considered and treated as affected by chronic pancreatitis. In spite of the tumour size and possible vascular infiltration, surgical exploration was considered. Total pancreatectomy was performed and final histology revealed a non-invasive papillary mucinous carcinoma of the pancreas. Twenty-six months after surgical resection the patient is alive and free of disease. In the present paper we re-assess the clinical history of this patient and review the most recent literature on such tumours.

Negative-pressure ventilation: better oxygenation and less lung injury.

RATIONALE: Conventional positive-pressure ventilation delivers pressure to the airways; in contrast, negative pressure is delivered globally to the chest and abdomen. OBJECTIVES: To test the hypothesis that ventilation with negative pressure results in better oxygenation and less injury than with positive pressure. METHODS: Anesthetized, surfactant-depleted rabbits were ventilated for 2.5 hours in pairs (positive or negative). Tidal volume was 12 ml . kg(-1), normocapnia was maintained by adjusting respiratory rate, and Fi(O(2)) was 1.0. MEASUREMENTS AND MAIN RESULTS: Lung injury was assessed with histologic scoring, perfusion using thermodilution (global perfusion), and injected intravascular microspheres (regional perfusion); and dynamic computed tomography was used to determine inflation patterns. Negative pressure was associated with a higher Pa(O(2)), a lower Pa-Pet(CO(2)) gradient (despite identical minute ventilation), and less lung injury. Lung perfusion (global and regional) was similar with positive and negative pressure. Positive end-expiratory pressure applied to the airway was more efficiently transmitted to the pleural space than comparable levels of negative end-expiratory pressure applied to the chest wall; however, the oxygenation associated with any level of end-expiratory lung volume was greater when achieved by negative versus positive pressure. Dynamic computed tomography suggested that lung distension achieved with negative pressure is characterized by greater proportions of normally aerated lung (with less atelectasis) during inspiration and at end-expiration. CONCLUSIONS: Negative-pressure ventilation results in superior oxygenation that is unrelated to lung perfusion and may be explained by more effective inflation of lung volume during both inspiration and expiration.

[Social withdrawal behaviour in infant: clinical and research interest]. / Comportement de retrait relationnel du jeune enfant: du concept à l'outil diagnostique.

The social withdrawal behaviour concept is presented, along with its historical background and its links to infant depression. Sustained social withdrawal behaviour in infancy is observed either with attachment disorders, in autism, sensory impairment, intense and chronic pain, or in interaction disorders and as effects of maternal depression on the infant. The alarm distress baby scale (ADBB) is a 8 item-assessment scale. It has been built to help screening early withdrawal behaviour, making use for example of the routine physical examination in a Well Baby clinic. Current clinical and research application and validations of the scale are presented.