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Vascular surgery patients have multiple comorbidities and are at high risk for perioperative complications. Aortic repair surgery has greatly evolved in recent years, with an increasing predominance of endovascular techniques (EVAR). The incidence of cardiac complications is significantly reduced with endovascular repair, but high-risk patients require postoperative ST-segment monitoring. Open aortic repair may portend a prohibitive risk of respiratory complications that could be a contraindication for surgery. This risk is greatly reduced in the case of an endovascular approach, and general anesthesia should be avoided whenever possible in the case of endovascular repair. Preoperative renal function and postoperative kidney injury are powerful determinants of short- and long-term outcome, so that preoperative risk stratification and secondary prevention are critical tasks. Intraoperative renal protection with selective renal and distal aortic perfusion is essential during open repair. EVAR has lower rates of postoperative renal failure compared to open repair, with approximately half the risk for acute kidney injury (AKI) and one-third of the risk of hemodialysis requirement. Spinal cord ischemia used to be the most distinctive and feared complication of aortic repair. The risk has significantly decreased since the beginning of aortic surgery, with advances in surgical technique and spinal protection protocols, and is lower with endovascular repair. Endovascular repair avoids extensive aortic dissection and aortic cross-clamping and is generally associated with reduced blood loss and less coagulopathy. The intensive care physician must be aware that aortic repair surgery has an impact on every organ system, and the importance of early recognition of organ failure cannot be overemphasized.

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INTRODUCTION: Dynamic obstruction of right ventricle outflow tract (RVOTO) is a rare condition that may acutely cause severe heart failure. It has been reported in some hypertrophic cardiomyopathies, after lung transplantation, and in some cases of hemodynamic instability after cardiopulmonary bypass. PRESENTATION OF CASE: We report the case of a 71-year-old man who developed severe hypotension during the induction of general anesthesia for surgical coronary revascularization. Hypotension did not respond to the initial treatment with vasoconstrictors and fluids. RVOTO was suspected during pulmonary artery catheterization because of the difficulty of the catheter tip to move from the right ventricle to the pulmonary artery and, successively, because of the finding of a large gradient between the systolic pressure in the right ventricle and in the pulmonary artery. The diagnosis was confirmed by transesophageal echocardiogram (TEE). Hemodynamics recovered after the infusion of cristalloids, 1L, and the suspension of vasoconstrictors and inotropes. DISCUSSION: This is the first case in which RVOTO was observed during the induction of general anesthesia. Although this is a rare condition, the diagnostic suspect is of outmost importance because treatment is mainly based on fluid administration, and drugs with positive inotropic properties (like most vasoconstrictors) are contraindicated. CONCLUSIONS: RVOTO is an unusual, but possible cause of severe arterial hypotension during general anesthesia induction. TEE is useful for the evaluation of severely hypotensive patients who do not respond to routine treatment with fluids and vasoconstrictors.

Background. As a rule, central venous catheters (CVC) should not be positioned in the right atrium (RA) to avoid the risk of perforation and cardiac tamponade. However, in ICUs where ECG monitoring can detect any initial damage of the atrial wall, CVCs may probably be safely positioned in the RA. We investigated whether mixed venous saturation (SvO2) was better estimated by measuring central venous saturation (ScvO2) in the RA or in the superior vena cava (SVC) in patients undergoing cardiac surgery. Methods. A CVC and a pulmonary artery catheter (PAC) were positioned before surgical coronary revascularization in sixty patients. Under transesophageal echocardiographic guidance, CVC tips were randomly positioned inside the RA (group A) or the SVC (group C). In each patient, eight pairs of blood samples were collected from CVC and PAC distal ports and saturation measured. Cardiac arrhythmias that occurred in the first 48 postoperative hours and CVC tip position on chest X-rays were also registered. Results. ScvO2 and SvO2 correlated better in group A (r=0.95) than in group C (r=0.84). The 95% interval of confidence of the gap between ScvO2 and SvO2 was narrower in group A (-6.9/+ 3.2 vs. -11.6/+5.5; p<.01). The incidence of arrhythmias was equal in the two groups (16.7%). On chest X-rays, CVC tips were 5.4 (SD=3.6) cm below the tracheal carina in group A and 5.3 (SD=3.9) cm in group C. Conclusion. In monitored patients, positioning CVC tips in the RA rather than in the SVC may allow closer estimates of SvO2 and may be safe. Yet, safety should be confirmed by further studies with larger samples of patients.

La cardiochirurgia determina l'insorgenza di danno renale quando valutato con Cistatina C o IL-18. Il trattamento con fenoldopam non modifica questa evenienza in modo significativo

Le complicanze intestinali dopo cardiochirurgia sono rare ma con elevata mortalità. Riportiamo l caso di un paziente coronaropatico, che ha sviluppato un addome acuto, con TAC fortemente sospetta per ischemia mesenterica

La Via Lattea è la galassia che ospita il Sistema Solare, sistema planetario di cui fa parte la Terra. Per questo motivo, il suo studio presenta delle difficoltà estranee allo studio delle altre galassie, a causa della prospettiva completamente diversa da cui la si osserva. Allo stesso tempo permette di ottenere delle informazioni molto dettagliate sui fenomeni su piccola scala, che non si possono ottenere per le altre galassie. In questo elaborato si vuole dare una panoramica delle caratteristiche strutturali e cinematiche della Via Lattea, presentando gli aspetti fondamentali dei metodi che permettono di desumere tali caratteristiche dalle osservazioni.

Uncertainties on the nature and efficiency of internal mixing processes in stars are becoming the dominant limitation to inferring accurate stellar ages. One particularly relevant uncertainty is that of the efficiency of additional mixing at the boundary of convective cores in the core hydrogen-burning phase. This project investigates a novel method of constraining such mixing processes, in particular those induced by rotation, by studying their imprint on the observed luminosity distribution and core-properties of low- to intermediate-mass core helium burning stars. Through the computation of single-age synthetic stellar populations using models that incorporate rotation-induced mixing, we have uncovered the appearance of extended red clumps within single-age clusters. The properties of these red clumps possess the potential to provide valuable insights into the efficiency of rotation-induced mixing processes, the origins of the observed extended red clumps and turn-offs, and to enhance the accuracy of age determinations. An initial assessment comparing the results with observations appears to support the plausibility of this scenario to some extent.

La Via Lattea è la galassia che ospita il Sistema Solare, sistema planetario di cui fa parte la Terra. Per questo motivo, il suo studio presenta delle difficoltà estranee allo studio delle altre galassie, a causa della prospettiva completamente diversa da cui la si osserva. Allo stesso tempo permette di ottenere delle informazioni molto dettagliate sui fenomeni su piccola scala, che non si possono ottenere per le altre galassie. In questo elaborato si vuole dare una panoramica delle caratteristiche strutturali e cinematiche della Via Lattea, presentando gli aspetti fondamentali dei metodi che permettono di desumere tali caratteristiche dalle osservazioni.