Sandra Rossi - Academia.edu (original) (raw)

Papers by Sandra Rossi

Journal of Clinical Monitoring and Computing

The measurement of cardiac output (CO) may be useful to improve the assessment of hemodynamics du... more The measurement of cardiac output (CO) may be useful to improve the assessment of hemodynamics during simulated scenarios. The purpose of this study was to evaluate the feasibility of introducing an uncalibrated pulse contour device (MostCare, Vytech, Vygon, Padova, Italy) into the simulation environment. MostCare device was plugged to a clinical monitor and connected to the METI human patient simulator (HPS) to obtain a continuous arterial waveform analysis and CO calculation. In six different simulated clinical scenarios (baseline, ventricular failure, vasoplegic shock, hypertensive crisis, hypovolemic shock and aortic stenosis), the HPS-CO and the MostCare-CO were simultaneously recorded. The level of concordance between the two methods was assessed by the Bland and Altman analysis. 150-paired CO values were obtained. The HPS-CO values ranged from 2.3 to 6.6 L min−1 and the MostCare-CO values from 2.8 to 6.4 L min−1. The mean difference between HPS-CO and MostCare-CO was − 0.3 L min−1 and the limits of agreement were − 1.5 and 0.9 L min−1. The percentage of error was 23%. A good correlation between HPS-CO and MostCare-CO was observed in each scenario of the study (r = 0.88). Although MostCare-CO tended to underestimate the CO over the study period, good agreements were found between the two methods. Therefore, a pulse contour device can be integrated into the simulation environment, offering the opportunity to create new simulated clinical settings.

Dermatol Argent, Sep 1, 1996

World Journal of Emergency Surgery

The acute phase management of patients with severe traumatic brain injury (TBI) and polytrauma re... more The acute phase management of patients with severe traumatic brain injury (TBI) and polytrauma represents a major challenge. Guidelines for the care of these complex patients are lacking, and worldwide variability in clinical practice has been documented in recent studies. Consequently, the World Society of Emergency Surgery (WSES) decided to organize an international consensus conference regarding the monitoring and management of severe adult TBI polytrauma patients during the first 24 hours after injury. A modified Delphi approach was adopted, with an agreement cut-off of 70%. Forty experts in this field (emergency surgeons, neurosurgeons, and intensivists) participated in the online consensus process. Sixteen recommendations were generated, with the aim of promoting rational care in this difficult setting.

Anesthesiology, Jan 25, 2016

A & A case reports, 2015

We report the case of a 48-year-old woman who developed severe septic shock and lung injury after... more We report the case of a 48-year-old woman who developed severe septic shock and lung injury after community-acquired pneumonia. She was supported on arteriovenous extracorporeal membrane oxygenation (ECMO) for 19 days. To facilitate decannulation and separation from ECMO, we began trials of high-frequency percussive ventilation (HFPV) using the volumetric diffusive respiration ventilator VDR-4 (Percussionaire Corp, Sandpoint, Idaho) for 4 consecutive days (1 before and 3 after). Decannulation was achieved successfully, and the patient was transferred to the floor 3 months later. During the 4 days of HFPV, the chest radiograph improved, as did gas exchange and clearance of pulmonary secretions. HFPV may be a promising strategy for improving lung recruitment and airway clearance during separation from ECMO in the critically ill patient.

Contributions to nephrology, 2004

... Inappropriate stimulation of these receptors have potential detrimental effects. Major concer... more ... Inappropriate stimulation of these receptors have potential detrimental effects. Major concern has always Dan/Rossi/Callegarin/Ronco 188 ... Chest 1997; 112: 235243. 14 Landry DW, Lewin HR, Gallant EM, et al: Vasopressin pressor hypersensitivity in vasodilatory septic shock. ...

Radiology, Aug 1, 2004

To assess whether characterization of solid focal liver lesions could be improved by using ultras... more To assess whether characterization of solid focal liver lesions could be improved by using ultrasonographic (US) contrast-specific modes after sulfur hexafluoride-filled microbubble contrast agent injection, as compared with lesion characterization achieved with preliminary baseline US. Four hundred fifty-two solid focal hepatic lesions that were considered indeterminate at baseline gray-scale and color Doppler US were examined after microbubble contrast agent injection performed by using low-acoustic-power contrast-specific modes during the arterial (10-40 seconds after injection), portal venous (50-90 seconds after injection), and late (100-300 seconds after injection) phases. Two readers independently and retrospectively reviewed baseline and contrast material-enhanced US scans and classified each depicted lesion as malignant or benign according to standard diagnostic criteria. Sensitivity, specificity, accuracy, and positive and negative predictive values and areas under the receiver operating characteristic curve (Az) were calculated by considering histologic analysis (317 patients) or contrast-enhanced helical computed tomography followed by serial US 3-6 months apart (135 patients) as the reference standards. Different contrast enhancement patterns were observed according to lesion characteristics. During the late phase, benign lesions were predominantly hyper- or isoechoic relative to the adjacent liver parenchyma, whereas malignant lesions were predominantly hypoechoic. Review of the contrast-enhanced US scans after baseline image review yielded significantly improved diagnostic performance (P &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;.05). Overall diagnostic accuracy was 49% before versus 85% after review of the contrast-enhanced scan for reader 1 and 51% before versus 88% after review of the contrast-enhanced scan for reader 2. Diagnostic confidence-that is, the Az-was 0.820 before versus 0.968 after review of the contrast-enhanced scan for reader 1 and 0.831 before versus 0.978 after review of the contrast-enhanced scan for reader 2. The use of contrast-specific modes with a sulfur hexafluoride contrast agent led to improved characterization of solid focal liver lesions.

The International Journal of Artificial Organs, 2015

Proceedings of the 2003 SBMO/IEEE MTT-S International Microwave and Optoelectronics Conference - IMOC 2003. (Cat. No.03TH8678), 2003

Ahstract-We describe the OMEGA test bed, an all-optical five-node IP over WDM re-configurable two... more Ahstract-We describe the OMEGA test bed, an all-optical five-node IP over WDM re-configurable two-layer network Its data plane is evaluated in physical impairments experiments, based on measnrements of BER, eye-diagram and OSNR, with emphasis on the influence of number of hops, number of channels, amplifier location (before or after the node), and channel power fluctuation after routing over different length paths. The OMEGA control plane provides protection and restoration functionalities with wavelength routing. Its operation is demonstrated in two transmission experiments: Gb-Ethernet and IP over WDM with protection at the optical layer.

European Journal of Obstetrics & Gynecology and Reproductive Biology, 2014

Brain Edema XI, 2000

Interest in tissue oxygen (PtiO2) monitoring is increasing. However the exact interactions betwee... more Interest in tissue oxygen (PtiO2) monitoring is increasing. However the exact interactions between ptiO2, systemic and cerebral variables are a matter of debate. Particularly, the relationship between ptiO2, cerebral oxygen supply and consumption needs to be clarified. We designed a model to achieve progressive Cerebral Blood Flow (CBF) reduction through 3 steps: 1. baseline, 2. CBF between 50-60% of the baseline, 3. CBF < 30% of the baseline. In 7 pigs, under general anaesthesia, Cerebral Perfusion Pressure (CPP) and CBF were reduced through the infusion of saline in a lateral ventricle. PtiO2 and CBF were monitored respectively through a Clark electrode (Licox, GMS) and laser doppler (Peri-Flux). Blood from superior sagittal sinus and from an arterial line was simultaneously drawn to calculate the artero-venous difference of oxygen (AVDO2). Brain oxygen supply was calculated by multiplying relative CBF change and arterial oxygen content. PtiO2 reflected CBF reductions, as it was 27.95 (+/- 10.15) mmHg during the first stage of intact CBF, declined to 14.77 (+/- 3.58) mmHg during the first CBF reduction, declined to 3.45 (+/- 2.89) mmHg during the second CBF reduction and finally fell to 0 mmHg when CBF was completely abolished. CBF changes were also followed by a decline in O2 supply and a parallel increase in AVDO2. This model allows stable and reproducible steps of progressive CBF reduction in which ptiO2 changes can be studied together with oxygen supply and consumption.

Intracranial Pressure and Brain Biochemical Monitoring, 2002

The aim of the present study was to assess the veno-arterial difference in pCO2 (delta pCO2) as a... more The aim of the present study was to assess the veno-arterial difference in pCO2 (delta pCO2) as an indicator of ischemia compared to the arteriovenous O2 difference (AVDO2). Staircase cerebral blood flow (CBF) reductions were obtained in seven domestic pigs by inducing intracranial hypertension: CBF 100%, 50-60% of baseline, 20-30% of baseline. ICP, MAP, CPP and CBF (Laser-Doppler method) were continuously recorded. The superior sagittal sinus was punctured to determine AVDO2 and delta pCO2. AVDO2 was 5.9 (+/- 1.78, range 3.3-7.4), 7.01 (+/- 1.31, range 5-8.9) and 8.17 (+/- 1.51, range 6.0-11.3) ml/100 ml in the three CBF steps (p = 0.001). CBF impairment was accompanied by the following increases in delta pCO2: from 10 (+/- 4, range 4-15) mmHg to 14.5 (+/- 4.11, range 10-27) mmHg, and to 31.2 (+/- 9.0, range 17-39) mmHg (p < 0.001). When CBF declines AVDO2 increases, indicating greater extraction of O2 to satisfy the aerobic metabolism. However, this mechanism can no longer compensate once a critical CBF threshold is reached. delta pCO2 rises slowly during moderate CBF reduction because of defective washout; the rise is impressive during marked CBF impairment when anaerobic metabolism takes place with proton buffering in CO2 and H2O. Therefore, when the brain's ability to compensate for low blood flow is exceeded, CO2 production outweighs O2 extraction.

Journal of Cardiovascular Medicine, 2013

Two related mechanisms occur as sepsis progresses to septic shock: intravascular refractory hypov... more Two related mechanisms occur as sepsis progresses to septic shock: intravascular refractory hypovolemia due to vascular endothelium dysfunction and, in more severe cases, primitive heart failure and contractility reduction. Whereas the role of vascular endothelium has been well recognized, different events, such as global ischemia, myocardial inflammation and biochemical toxicity, have been hypothesized as underlying causes of myocardial dysfunction. However, in current clinical practice the real mechanisms leading to heart failure and contractility impairment in patients with septic shock remain uncertain. Cardiac magnetic resonance (CMR), because of its capability to characterize myocardial tissue &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;in vivo&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39; can discriminate between ischemic and inflammatory injuries, allowing the more appropriate therapeutic strategy. The case presented herein highlights the usefulness of CMR in this subset of patients.

2006 International Telecommunications Symposium, 2006

The main interests of the GIGA Project are the deployment of Optical Network Technology, Network ... more The main interests of the GIGA Project are the deployment of Optical Network Technology, Network Services and Applications, Experimental Telecommunication Services and Scientific Applications. In the context of this Project, our research group has been working in the design of a IP/WDM Control Plane to integrate the IP/MPLS Client Network with the Optical Transport Network (WDM), according to the GMPLS and ASON specifications. We propose a UNI (User Network Interface) architecture providing an independent signaling protocol to integrate the Client and the Optical Transport Networks. The proposed UNI architecture maintains unchanged the client and transport networks signaling semantics for the GIGA testbed network. The paper describes how the designed architecture supports the independence of the signaling protocol and presents the prototype implemented to validate the architecture.

Respiratory Research, 2011

Background: Patients with Adult Respiratory Distress Syndrome (ARDS) and Acute Lung Injury (ALI) ... more Background: Patients with Adult Respiratory Distress Syndrome (ARDS) and Acute Lung Injury (ALI) have low concentrations of disaturated-phosphatidylcholine and surfactant protein-B in bronchoalveolar lavage fluid. No information is available on their turnover.

Oncology, 1996

In two consecutive series of patients with hepatocellular carcinoma (HCC), we compared clinico-la... more In two consecutive series of patients with hepatocellular carcinoma (HCC), we compared clinico-laboratory and ultrasonographic characteristics, diagnostic work-up, survival of untreated patients and, finally, therapeutic choices. In addition of the clinical examination, we tested for blood serum alpha-fetoprotein levels, HBsAg and anti-HCV antibodies. Ultrasonography was performed in all the patients. In most cases, a pathologic diagnosis was obtained by ultrasound-guided fine-needle biopsy. As curative treatment we considered open surgery, percutaneous alcohol injection and radio frequency thermal ablation. In the second series, we observed an increased number of patients with compensated cirrhosis and with small HCCs, therefore the number of patients undergoing a potentially curative treatment was higher. The percentage of multiple tumours was comparable in two series implying the presence of two kinds of HCC, different ¿ab initio'. The survival rate of untreated patients was better in the second series.

Neurosurgery, 2000

To evaluate, in a prospective, observational study, whether bilateral monitoring of jugular bulb ... more To evaluate, in a prospective, observational study, whether bilateral monitoring of jugular bulb oxyhemoglobin saturation (SjO2), in addition to standard monitoring, results in modification of the management of severe head trauma. The patients underwent bilateral jugular bulb cannulation and observation at 8-hour intervals, during which SjO2 was measured and the neurological condition and physiological variables were assessed. The study group was responsible for evaluating whether the physician's decision-making process was influenced by the detection of SjO2 abnormalities. The SjO2 discrepancy in simultaneous bilateral samples was also evaluated to determine whether it interfered with the interpretation of data and with clinical decision-making. The SjO2-related complications were monitored. Thirty patients underwent 319 observations. In 96% of patients, SjO2 was normal or high and had no influence on the diagnostic or therapeutic strategies. Treatment decisions were dictated by changes in clinical status and in intracranial and cerebral perfusion pressure. When these parameters were abnormal, treatment was administered, even if SjO2 was normal (101 observations). Conversely, when SjO2 was the only detected abnormality (34 observations), no treatment was administered. Abnormally low SjO2 values, caused by hypovolemia and hypocapnia, were detected in 3.4% of observations and actually modified the management. The discrepancies in simultaneous bilateral samples were substantial and gave rise to relevant interpretation problems. Fifteen percent of jugular catheters showed evidence of bacterial colonization. Intermittent SjO2 monitoring did not substantially influence the management of severe head trauma. Therefore, recommendation for its routine use in all patients seems inadvisable, and indications for this invasive method should no longer be defined on the basis of experts' opinions, but rather on randomized, prospective studies.

Journal of Neurotrauma, 2001

We investigated the changes in brain oxygen tension (ptiO2) after ventilation with pure O2 in ord... more We investigated the changes in brain oxygen tension (ptiO2) after ventilation with pure O2 in order to (1) clarify the pathophysiology of O2 exchange in the cerebral microcirculation; and (2) investigate the relationship between brain O2 tension, O2 delivery, and consumption in steady-state conditions during stepwise cerebral blood flow (CBF) reductions. A swine model was developed to reduce CBF in three stable steps: (1) baseline (CBF 100%), (2) CBF of 50-60% of baseline, and (3) CBF of <30% of baseline. CBF was reduced by infusing saline into the left lateral ventricle through a catheter connected with an infusion pump. At each step, hyperoxia was tested by increasing the inspired oxygen fraction up to 100%, PtiO2 reflected the CBF reductions, since it was respectively 27.95 (+/-10.15), 14.77 (+/-3.58), and 3.45 (+/-2.89) mm Hg during the three CBF steps. Hyperoxia was followed by an increase in ptiO2, although the increase was significantly lower when hyperoxia was applied during progressive ischemia. O2 supply to the brain did not change during hyperoxia. Arteriovenous oxygen difference (AVDO2) decreased during the phases of intact CBF and moderate impairment, but not during the phase of severe CBF reduction. In conclusion, ptiO2 reductions closely reflect the imbalance between oxygen delivery and demand; this implies a link between low ptiO2 and defective O2 supply due to impaired CBF. However, this relation is not necessarily reciprocal, since manipulating brain oxygen tension does not always influence brain oxygen delivery, as in the case of ventilation with pure oxygen.

Journal of Neurology, Neurosurgery & Psychiatry, 2001

Objectives-To assess the frequency of hyperthermia in a population of acute neurosurgical patient... more Objectives-To assess the frequency of hyperthermia in a population of acute neurosurgical patients; to assess the relation between brain temperature (ICT) and core temperature (Tc); to investigate the eVect of changes in brain temperature on intracranial pressure (ICP). Methods-The study involved 20 patients (10 severe head injury, eight subarachnoid haemorrhage, two neoplasms) with median Glasgow coma score (GCS) 6. ICP and ICT were monitored by an intraventricular catheter coupled with a thermistor. Internal Tc was measured in the pulmonary artery by a Swan-Ganz catheter. Results-Mean ICT was 38.4 (SD 0.8) and mean Tc 38.1 (SD 0.8)°C; 73% of ICT and 57.5% of Tc measurements were >38°C. The mean diVerence between ICT and Tc was 0.3 (SD 0.3)°C (range −0.7 to 2.3°C) (p=0. 0001). Only in 12% of patients was Tc higher than ICT. The main reason for the diVerences between ICT and Tc was body core temperature: the diVerence between ICT and Tc increased significantly with body core temperature and fell significantly when this was lowered. The mean gradient between ICT and Tc was 0.16 (SD 0.31)°C before febrile episodes (ICT being higher than Tc), and 0.41 (SD 0.38)°C at the febrile peak (p<0.05). When changes in temperature were considered, ICT had a profound influence on ICP. Increases in ICT were associated with a significant rise in ICP, from 14.9 (SD 7.9) to 22 (SD 10.4) mm Hg (p<0.05). As the fever ebbed there was a significant decrease in ICP, from 17.5 (SD 8.62) to 16 (SD 7.76) mm Hg (p=0.02). Conclusions-Fever is extremely frequent during acute cerebral damage and ICT is significantly higher than Tc. Moreover, Tc may underestimate ICT during the phases when temperature has the most impact on the intracranial system because of the close association between increases in ICT and ICP. (J Neurol Neurosurg Psychiatry 2001;71:448-454)