Schnider and Eleveld Models for Propofol Target-Controlled Infusion Anesthesia: A Clinical Comparison.

BACKGROUND: Various pharmacokinetic/pharmacodynamic (PK/PD) models have been developed to accurately dose propofol administration during total intravenous anesthesia with target-controlled infusion (TIVA-TCI). We aim to clinically compare the performance of the Schnider model and the new and general-purpose Eleveld PK/PD model during TIVA-TCI. METHODS: We conducted a prospective observational study at a single center, enrolling 78 female patients, including 37 adults (aged < 65 years) and 41 elderly patients (aged ≥ 65 years). These patients underwent breast surgery with propofol-remifentanil TIVA-TCI guided by the bispectral index (BIS) for depth of anesthesia monitoring (target value 40-60) and the surgical plethysmographic index (SPI) for antinociception monitoring (target value 20-50) without neuromuscular blockade. The concentration at the effect site of propofol (CeP) at loss of responsiveness (LoR) during anesthesia maintenance (MA) and at return of responsiveness (RoR), the duration of surgery and anesthesia (min), the time to RoR (min), the propofol total dose (mg), the deepening of anesthesia events (DAEs), burst suppression events (BSEs), light anesthesia events (LAEs) and unwanted spontaneous responsiveness events (USREs) were considered to compare the two PK/PD models. RESULTS: Patients undergoing BIS-SPI-guided TIVA-TCI with the Eleveld PK/PD model showed a lower CeP at LoR (1.7 (1.36-2.25) vs. 3.60 (3.00-4.18) µg/mL, p < 0.001), higher CePMA (2.80 (2.55-3.40) vs. 2.30 (1.80-2.50) µg/mL, p < 0.001) and at RoR (1.48 (1.08-1.80) vs. 0.64 (0.55-0.81) µg/mL, p < 0.001) than with the Schnider PK/PD model. Anesthetic hysteresis was observed only in the Schnider PK/PD model group (p < 0.001). DAEs (69.2% vs. 30.8%, p = 0.001) and BSEs (28.2% vs. 5.1%, p = 0.013) were more frequent with the Eleveld PK/PD model than with the Schnider PK/PD model in the general patient population. DAEs (63.2% vs. 27.3%, p = 0.030) and BSEs (31.6% vs. 4.5%, p = 0.036) were more frequent with the Eleveld PK/PD model than with the Schnider PK/PD model in the elderly. CONCLUSIONS: The Schnider and Eleveld PK/PD models impact CePs differently. A greater incidence of DAEs and BSEs in the elderly suggests more attention is necessary in this group of patients undergoing BIS-SPI-guided TIVA-TCI with the Eleveld PK/PD than with the Schnider model.

Novel three-dimensional acellular dermal matrix for prepectoral breast reconstruction: First year in review with BRAXON® Fast.

Implant-based breast reconstruction is part of breast cancer treatment, and increasingly optimized reconstructive procedures exploit highly biocompatible materials to ensure enhanced aesthetic-functional results. Acellular dermal matrices (ADMs) are collagen-based materials that made prepectoral implant placement possible, thanks to their bioactive antifibrosis action. Recently, the first three-dimensional ADM, BRAXON® Fast, has been produced. Its 3D design represents the technological evolution of BRAXON® ADM, a flat collagen matrix, and allows for a time-saving complete wrapping of the synthetic prosthesis, thus creating a total biological interface on the implant with patient's tissues. Here, we report our experience on the first 23 eligible patients who received BRAXON® Fast-assisted prepectoral reconstruction. On a total of 27 breasts, the overall complication rate was 11.1%, including one minor seroma (3.7%), one case of necrosis (3.7%), and one implant removal due to infection. As new-generation devices, 3D ADMs showed an effective performance, allowing to reduce the overall exposure time for implant preparation and providing an optimal safety profile.

Elaboration of a nomogram to predict nonsentinel node status in breast cancer patients with positive sentinel node, intraoperatively assessed with one step nucleic amplification: Retrospective and validation phase.

BACKGROUND: Tumor-positive sentinel lymph node (SLN) biopsy results in a risk of non sentinel node metastases in micro- and macro-metastases ranging from 20 to 50%, respectively. Therefore, most patients underwent unnecessary axillary lymph node dissections. We have previously developed a mathematical model for predicting patient-specific risk of non sentinel node (NSN) metastases based on 2460 patients. The study reports the results of the validation phase where a total of 1945 patients were enrolled, aimed at identifying a tool that gives the possibility to the surgeon to choose intraoperatively whether to perform or not axillary lymph node dissection (ALND). METHODS: The following parameters were recorded: Clinical: hospital, age, medical record number; Bio pathological: Tumor (T) size stratified in quartiles, grading (G), histologic type, lymphatic/vascular invasion (LVI), ER-PR status, Ki 67, molecular classification (Luminal A, Luminal B, HER-2 Like, Triple negative); Sentinel and non-sentinel node related: Number of NSNs removed, number of positive NSNs, cytokeratin 19 (CK19) mRNA copy number of positive sentinel nodes stratified in quartiles. A total of 1945 patients were included in the database. All patient data were provided by the authors of this paper. RESULTS: The discrimination of the model quantified with the area under the receiver operating characteristics (ROC) curve (AUC), was 0.65 and 0.71 in the validation and retrospective phase, respectively. The calibration determines the distance between predicted outcome and actual outcome. The mean difference between predicted/observed was 2.3 and 6.3% in the retrospective and in the validation phase, respectively. The two values are quite similar and as a result we can conclude that the nomogram effectiveness was validated. Moreover, the ROC curve identified in the risk category of 31% of positive NSNs, the best compromise between false negative and positive rates i.e. when ALND is unnecessary (<31%) or recommended (>31%). CONCLUSIONS: The results of the study confirm that OSNA nomogram may help surgeons make an intraoperative decision on whether to perform ALND or not in case of positive sentinel nodes, and the patient to accept this decision based on a reliable estimation on the true percentage of NSN involvement. The use of this nomogram achieves two main gools: 1) the choice of the right treatment during the operation, 2) to avoid for the patient a second surgery procedure.

Haptic feedback for enhancing realism of walking simulations.

In this paper, we describe several experiments whose goal is to evaluate the role of plantar vibrotactile feedback in enhancing the realism of walking experiences in multimodal virtual environments. To achieve this goal we built an interactive and a noninteractive multimodal feedback system. While during the use of the interactive system subjects physically walked, during the use of the noninteractive system the locomotion was simulated while subjects were sitting on a chair. In both the configurations subjects were exposed to auditory and audio-visual stimuli presented with and without the haptic feedback. Results of the experiments provide a clear preference toward the simulations enhanced with haptic feedback showing that the haptic channel can lead to more realistic experiences in both interactive and noninteractive configurations. The majority of subjects clearly appreciated the added feedback. However, some subjects found the added feedback unpleasant. This might be due, on one hand, to the limits of the haptic simulation and, on the other hand, to the different individual desire to be involved in the simulations. Our findings can be applied to the context of physical navigation in multimodal virtual environments as well as to enhance the user experience of watching a movie or playing a video game.

Sentinel lymph node metastasis from mammary ductal carcinoma in situ with microinvasion.

Axillary lymph node dissection (ALND) in patients with ductal carcinoma in situ with microinvasion (DCISM) of the breast was controversial, because of the relevant morbidity incurred by the procedure and the low incidence of axillary involvement. The introduction of the sentinel lymph node (SLN) biopsy as a minimally invasive procedure for axillary staging has prompted new interest in this issue. However, as DCISM is a rare type of cancer, data on the incidence of SLN metastasis are scarce. The aim of the present paper was therefore to assess the prevalence of SLN metastasis in a multi-institutional series of DCISM patients, in order to ascertain whether SLN biopsy might be justified as a standard procedure in the presence of microinvasive cancer. Between 1999 and 2004, 43 patients with a diagnosis of DCISM underwent SLN biopsy. Microinvasion was defined as one or more foci of invasion beyond the basal membrane, none exceeding 1mm. SLNs were examined following haematoxylin-eosin and immunohistochemical staining. SLN metastases were found in four out of 43 cases (9.3%). In one patient, SLN contained only micrometastasis. All four patients with positive SLN underwent complete ALND and in all these cases further metastatic axillary nodes were found. In conclusion, given the relevant incidence of nodal metastases and the low morbidity of the procedure, we believe that SLN biopsy should be considered in all patients with a diagnosis of DCISM. In cases of SLN involvement, even if micrometastatic, our policy is to perform a complete ALND.

Role of axillary sentinel lymph node biopsy in patients with pure ductal carcinoma in situ of the breast.

BACKGROUND: Sentinel lymph node (SLN) biopsy is an effective tool for axillary staging in patients with invasive breast cancer. This procedure has been recently proposed as part of the treatment for patients with ductal carcinoma in situ (DCIS), because cases of undetected invasive foci and nodal metastases occasionally occur. However, the indications for SLN biopsy in DCIS patients are controversial. The aim of the present study was therefore to assess the incidence of SLN metastases in a series of patients with a diagnosis of pure DCIS. METHODS: A retrospective evaluation was made of a series of 102 patients who underwent SLN biopsy, and had a final histologic diagnosis of pure DCIS. Patients with microinvasion were excluded from the analysis. The patients were operated on in five Institutions between 1999 and 2004. Subdermal or subareolar injection of 30-50 MBq of 99 m-Tc colloidal albumin was used for SLN identification. All sentinel nodes were evaluated with serial sectioning, haematoxylin and eosin staining, and immunohistochemical analysis for cytocheratin. RESULTS: Only one patient (0.98%) was SLN positive. The primary tumour was a small micropapillary intermediate-grade DCIS and the SLN harboured a micrometastasis. At pathologic revision of the specimen, no detectable focus of microinvasion was found. CONCLUSION: Our findings indicate that SLN metastases in pure DCIS are a very rare occurrence. SLN biopsy should not therefore be routinely performed in patients who undergo resection for DCIS. SLN mapping can be performed, as a second operation, in cases in which an invasive component is identified in the specimen. Only DCIS patients who require a mastectomy should have SLN biopsy performed at the time of breast operation, since in these cases subsequent node mapping is not feasible.

Number of metastatic sentinel nodes as predictor of axillary involvement in patients with breast cancer.

BACKGROUND AND OBJECTIVES: More than half of patients with positive sentinel node (SN) have no metastases in non-sentinel nodes (NSNs) on axillary lymph node dissection (ALND). The aim of this study was to investigate factors predictive of NSNs involvement, in order to identify patients with metastatic disease confined to the SN which might avoid ALND. METHODS: ALND was performed in 167 patients with metastatic SN. Axillary NSNs status was correlated with the size of SN metastases, the size of the primary tumor and the occurrence of lymphovascular invasion. In 72 cases, the radiotracer (Tc-99m albumin colloid) marked multiple (in most cases 2 or 3) nodes. In this group, NSNs status was correlated with the number of metastatic radioactive nodes (1 or > 1), and with the above mentioned histopathologic factors. RESULTS: NSNs metastases were found in 57/167 cases (34.1%), the rate increasing proportionate to the size of both SN metastases (p < 0.0001) and primary tumor (p = 0.0075), while no significant correlation was found for lymphovascular invasion (p = 0.1769). At univariate and multivariate analysis of findings from the 72 cases with multiple probe-detected hot nodes, positivity in more than one hot node was the strongest predictor of NSN involvement (p = 0.0019). CONCLUSIONS: The identification and excision of multiple hot nodes can be useful in the prediction of NSNs involvement in patients with metastatic SN.

Usefulness of ultrasound scissors in reducing serous drainage after axillary dissection for breast cancer: a prospective randomized clinical study.

Axillary dissection is usually associated with prolonged serous drainage that may result in several complications. We analyzed whether the use of ultrasound scissors may decrease the total amount of drainage from the axilla (AD) in patients requiring curative surgery for breast cancer. Seventy-six women (median age, 56 years; range, 32-73 years) with confirmed pT1-3, N0-1 breast cancer were prospectively randomly assigned to undergo mastectomy or breast-conserving surgery with axillary dissection by either using (group A) or not using (group B) ultrasound scissors. Overall, there was a linear relationship (P < 0.05) between AD and both total number of the removed nodes and body mass index, whereas no correlation (P = NS) was found with age and size of the tumor. Total AD was higher (492 +/- 153 vs. 408 +/- 136 mL, P = 0.013) in group B, whereas the postoperative hospital stay was shorter (2.4 +/- 0.6 vs. 2.7 +/- 0.7 days, P = NS) in group A. The three-way analysis of covariance using the number of total removed nodes as covariate showed that lymph node status, type of operation, and technique for axillary dissection significantly (P < 0.05) correlated with AD. In conclusion, our initial study shows that the use of ultrasound scissors significantly reduced total AD in patients requiring axillary dissection and may shorten hospital stay.

[Acute abdomen due to a strangulated and perforated para-esophageal hernia. A case report]. / Addome acuto da ernia paraesofagea strozzata e perforata. Caso clinico.

Para-oesophageal hiatus hernia, a condition in which the fundus and part of the body of the stomach wrapped in a peritoneal sac herniate into the mediastinum, is a relatively uncommon entity. It tends to grow progressively and may become so large as to lead to symptoms of intrathoracic organ compression. In some exceptional cases, the entire stomach together with other abdominal viscera might herniate through the hiatus into the thorax. Paraesophageal hiatus hernias are characterised clinically by vague symptomatology, absent gastro-oesophageal reflux, and possible onset of gastric volvulus, generally without consequent incarceration of the portion of the herniated organ. Such an event is uncommon but dangerous and life-threatening. These cases often require resection of the incarcerated viscera, followed by hiatoplasty and Nissen fundoplication. The authors report on the case of a patient presenting with acute abdomen as a result of incarcerated and perforated para-oesophageal hiatus hernia.

[Combined ROLL and sentinel lymph node: a new strategy in radio-guided surgery]. / Metodica abbinata roll-linfonodo sentinella: nuove strategie della chirurgia radioguidata.

Radioguided surgery for the treatment of breast cancer is becoming the gold standard for both diagnosis and therapy. The main rule in using ROLL is perfect localization of non-palpable lesions and minimal invasiveness of excision. The same criteria apply to the sentinel lymph node technique. Clinically occult breast lesions, which require an exact histological diagnosis, are most frequently detected as the result of mammographic screening. The authors show that the ROLL technique for histological diagnosis may alter the subdermal lymphatic drainage so that the sentinel node cannot be found at later surgery. The aim of this study was to report the authors' experience with a combined ROLL and sentinel lymph node biopsy technique for the diagnosis and treatment of occult cancer of the breast.