Epidemiology, practice of ventilation and outcome for patients at increased risk of postoperative pulmonary complications

BACKGROUND Limited information exists about the epidemiology and outcome of surgical patients at increased risk of postoperative pulmonary complications (PPCs), and how intraoperative ventilation was managed in these patients. OBJECTIVES To determine the incidence of surgical patients at increased risk of PPCs, and to compare the intraoperative ventilation management and postoperative outcomes with patients at low risk of PPCs. DESIGN This was a prospective international 1-week observational study using the ‘Assess Respiratory Risk in Surgical Patients in Catalonia risk score’ (ARISCAT score) for PPC for risk stratification. PATIENTS AND SETTING Adult patients requiring intraoperative ventilation during general anaesthesia for surgery in 146 hospitals across 29 countries. MAIN OUTCOME MEASURES The primary outcome was the incidence of patients at increased risk of PPCs based on the ARISCAT score. Secondary outcomes included intraoperative ventilatory management and clinical outcomes. RESULTS A total of 9864 patients fulfilled the inclusion criteria. The incidence of patients at increased risk was 28.4%. The most frequently chosen tidal volume (VT) size was 500 ml, or 7 to 9 ml kg1 predicted body weight, slightly lower in patients at increased risk of PPCs. Levels of positive end-expiratory pressure (PEEP) were slightly higher in patients at increased risk of PPCs, with 14.3% receiving more than 5 cmH2O PEEP compared with 7.6% in patients at low risk of PPCs (P < 0.001). Patients with a predicted preoperative increased risk of PPCs developed PPCs more frequently: 19 versus 7%, relative risk (RR) 3.16 (95% confidence interval 2.76 to 3.61), P < 0.001) and had longer hospital stays. The only ventilatory factor associated with the occurrence of PPCs was the peak pressure. CONCLUSION The incidence of patients with a predicted increased risk of PPCs is high. A large proportion of patients receive high VT and low PEEP levels. PPCs occur frequently in patients at increased risk, with worse clinical outcome

Epidemiology, practice of ventilation and outcome for patients at increased risk of postoperative pulmonary complications: LAS VEGAS - An observational study in 29 countries

BACKGROUND Limited information exists about the epidemiology and outcome of surgical patients at increased risk of postoperative pulmonary complications (PPCs), and how intraoperative ventilation was managed in these patients. OBJECTIVES To determine the incidence of surgical patients at increased risk of PPCs, and to compare the intraoperative ventilation management and postoperative outcomes with patients at low risk of PPCs. DESIGN This was a prospective international 1-week observational study using the ‘Assess Respiratory Risk in Surgical Patients in Catalonia risk score’ (ARISCAT score) for PPC for risk stratification. PATIENTS AND SETTING Adult patients requiring intraoperative ventilation during general anaesthesia for surgery in 146 hospitals across 29 countries. MAIN OUTCOME MEASURES The primary outcome was the incidence of patients at increased risk of PPCs based on the ARISCAT score. Secondary outcomes included intraoperative ventilatory management and clinical outcomes. RESULTS A total of 9864 patients fulfilled the inclusion criteria. The incidence of patients at increased risk was 28.4%. The most frequently chosen tidal volume (V T) size was 500 ml, or 7 to 9 ml kg−1 predicted body weight, slightly lower in patients at increased risk of PPCs. Levels of positive end-expiratory pressure (PEEP) were slightly higher in patients at increased risk of PPCs, with 14.3% receiving more than 5 cmH2O PEEP compared with 7.6% in patients at low risk of PPCs (P ˂ 0.001). Patients with a predicted preoperative increased risk of PPCs developed PPCs more frequently: 19 versus 7%, relative risk (RR) 3.16 (95% confidence interval 2.76 to 3.61), P ˂ 0.001) and had longer hospital stays. The only ventilatory factor associated with the occurrence of PPCs was the peak pressure. CONCLUSION The incidence of patients with a predicted increased risk of PPCs is high. A large proportion of patients receive high V T and low PEEP levels. PPCs occur frequently in patients at increased risk, with worse clinical outcome.</p

Parasitic conduction in a 0.13 μ\mum CMOS technology at low temperature

Low temperature measurements at 4.2 K and 77 K are performed on n- and p-MOSFETs of a 0.13 $\mu$m CMOS technology. Two parasitic current contributions are identified in the subthreshold regime and strong inversion at 4.2 K. The first one is related to a parasitic parallel conduction inherent to Shallow Trench Isolation. Whereas the second one, resulting in a second peak in the linear transconductance, is discussed in terms of a stronger impact of substrate majority carriers due to a higher substrate resistivity at 4.2 K. The measured substrate current in n-MOSFETs is probably originating from electrons tunneling from the substrate valence band to the gate. At 4.2 K, the substrate current induces a reduction of the threshold voltage resulting in the measured “kink" of the $\rm I_D(V_G)$ characteristic and the second transconductance peak at low drain bias.

Low temperature operation of 0.13 μ\mum Partially-Depleted SOI nMOSFETs with floating body

An extended low temperature study of 0.13 $\mu$m Partially-Depleted Silicon-On-Insulator nMOSFETs without body contact is carried out. The impact of HALO doping characteristics on device output performance is investigated. The electrical properties of the technology are explored in terms of circuit applications both in digital and analog sense. The occurrence of inherent parasitic bipolar effects is also studied.

Update on scribe–cleave–passivate (SCP) slim edge technology for silicon sensors: Automated processing and radiation resistance

We pursue scribe–cleave–passivate (SCP) technology for making “slim edge” sensors. The goal is to reduce the inactive region at the periphery of the devices while maintaining their performance. In this paper we report on two aspects of the current efforts. The first one involves fabrication options for mass production. We describe the automated cleaving tests and a simplified version of SCP post-processing of n-type devices. Another aspect is the radiation resistance of the passivation. We report on the radiation tests of n- and p-type devices with protons and neutrons

Weak quasielastic electroproduction of hyperons with polarization observables

With the availability of high luminosity electron beam at the accelerators, there is now the possibility of studying weak quasielastic hyperon production off the proton, i.e. $e^-p \to \nu_e Y(Y=\Lambda,\Sigma^0)$, which will enable the determination of the nucleon-hyperon vector and axial-vector transition form factors at high $Q^2$ in the strangeness sector and provide test of the Cabibbo model, G-invariance, CVC, PCAC hypotheses and SU(3) symmetry. In this work, we have studied the total cross section, differential cross section as well as the longitudinal and perpendicular components of polarization of the final hyperons ($\Lambda$ and $\Sigma^0$ produced in these reactions) and presented numerical results for these observables and their sensitivity to the transition form factors.Comment: 14 pages, 10 figures, 2 table

Cerebral aspergillosis due to Aspergillus fumigatus in AIDS patient: first culture - proven case reported in Brazil Aspergilosis cerebral causada por Aspergillus fumigatus en paciente con SIDA: primer reporte de caso demostrado por cultivo en Brasil

Cerebral aspergillosis is a rare cause of brain expansive lesion in AIDS patients. We report the first culture-proven case of brain abscess due to Aspergillus fumigatus in a Brazilian AIDS patient. The patient, a 26 year-old male with human immunodeficiency virus (HIV) infection and history of pulmonary tuberculosis and cerebral toxoplasmosis, had fever, cough, dyspnea, and two episodes of seizures. The brain computerized tomography (CT) showed a bi-parietal and parasagittal hypodense lesion with peripheral enhancement, and significant mass effect. There was started anti-Toxoplasma treatment. Three weeks later, the patient presented mental confusion, and a new brain CT evidenced increase in the lesion. He underwent brain biopsy, draining 10 mL of purulent material. The direct mycological examination revealed septated and hyaline hyphae. There was started amphotericin B deoxycholate. The culture of the material demonstrated presence of the Aspergillus fumigatus. The following two months, the patient was submitted to three surgeries, with insertion of drainage catheter and administration of amphotericin B intralesional. Three months after hospital admission, his neurological condition suffered discrete changes. However, he died due to intrahospital pneumonia. Brain abscess caused by Aspergillus fumigatus must be considered in the differential diagnosis of the brain expansive lesions in AIDS patients in Brazil.<br>La aspergilosis cerebral es una causa rara de lesión expansiva cerebral en pacientes con SIDA. Presentamos el primer reporte de un absceso cerebral causado por Aspergillus fumigatus en un paciente brasileño con SIDA. El paciente, de 26 años de edad, presentaba antecedentes de infección por el virus de la inmunodeficiencia humana (VIH), tuberculosis pulmonar y toxoplasmosis cerebral. Manifestó fiebre, tos, disnea y dos episódios de convulsiones. La tomografía computadorizada (TC) demostró una lesión hipodensa parasagital y bi-parietal con realce periférico e importante efecto de masa. Se inició tratamiento anti-Toxoplasma. Tres semanas después, el paciente evidenció confusión mental y una nueva TC de cráneo mostró aumento de la lesión. Se realizó biopsia cerebral con drenaje de 10 mL de material purulento. El examen micológico directo reveló hifas hialinas septadas. Se inició anfotericina B deoxicolato. La cultura del material demostró presencia de Aspergillus fumigatus. En los siguientes dos meses el paciente fue sometido a otras tres cirugías, insertándose un catéter de drenaje y administrándose anfotericina B intralesional. Tres meses después de la admisión hospitalaria, la condición neurológica del paciente sufrió discretos cambios. Sin embargo, falleció debido a neumonia intrahospitalaria. Aunque muy raros, los abscesos cerebrales causados por Aspergillus fumigatus deben ser considerados en el diagnóstico diferencial de las lesiones expansivas cerebrales en pacientes con SIDA