Carbon dioxide insufflation deflects airborne particles from an open surgical wound model.

BACKGROUND: Surgical site infections remain a significant burden on healthcare systems and may benefit from new countermeasures. AIM: To assess the merits of open surgical wound CO2 insufflation via a gas diffuser to reduce airborne contamination, and to determine the distribution of CO2 in and over a wound. METHODS: An experimental approach with engineers and clinical researchers was employed to measure the gas flow pattern and motion of airborne particles in a model of an open surgical wound in a simulated theatre setting. Laser-illuminated flow visualizations were performed and the degree of protection was quantified by collecting and characterizing particles deposited in and outside the wound cavity. FINDINGS: The average number of particles entering the wound with a diameter of <5µm was reduced 1000-fold with 10L/min CO2 insufflation. Larger and heavier particles had a greater penetration potential and were reduced by a factor of 20. The degree of protection was found to be unaffected by exaggerated movements of hands in and out of the wound cavity. The steady-state CO2 concentration within the majority of the wound cavity was >95% and diminished rapidly above the wound to an atmospheric level (∼0%) at a height of 25mm. CONCLUSION: Airborne particles were deflected from entering the wound by the CO2 in the cavity akin to a protective barrier. Insufflation of CO2 may be an effective means of reducing intraoperative infection rates in open surgeries.

Dependence of the electron-cloud instability on the beam energy.

The electron cloud (EC) can be formed in the beam pipe of a circular accelerator if the secondary emission yield (SEY) of the inner surface is larger than 1, and it can detrimentally affect the circulating beam. Understanding the underlying physics and defining the scaling laws of this effect is indispensable to steer the upgrade plans of the existing machines and the design of new ones. The single bunch EC instability (ECI) is shown to be strongly affected by the transverse beam size. Transversely, smaller beams going through an electron cloud generate higher electron peak densities and lower the intensity threshold to make the beam unstable. In particular, since higher energy beams have smaller transverse sizes (for equal normalized transverse emittances), the scaling of the ECI threshold with the beam energy turns out to be surprisingly unfavorable.

Characteristics of the patients referred to a Hypertension Unit between 1989 and 2003.

The level of blood pressure, the type of antihypertensive treatment and the prevalence of resistant hypertension at the first examination were evaluated in 6254 patients referred to a hospital Hypertension Unit from 1989 to 2003. From 1989-1993 to 1999-2003, we observed a reduced prevalence of grade 2 and grade 3 hypertension, and an increase in the prevalence of grade 1 hypertension, the proportion of treated subjects, the average number of antihypertensive drugs per patient and the prevalence of resistant hypertension.

Changes in autonomic nervous function over a 5-year period in non-insulin-dependent diabetic patients.

One hundred and eight non-insulin-dependent diabetic patients who had been tested for autonomic dysfunction in 1984/85 were re-evaluated 5 years later. Autonomic function was assessed by means of four cardiovascular tests (heart rate variation during deep breathing and standing, and blood pressure variation after standing and sustained handgrip). Eighteen subjects were lost to follow-up; in the 90 patients who completed the study, both the deep breathing and the handgrip test significantly worsened (respectively from 13.7 +/- 7.8 to 11.6 +/- 6.3 beats min-1 p < 0.01, and from 16.9 +/- 8.2 to 12.7 +/- 7.1 mmHg, p < 0.001), whereas both the 30:15 ratio and the variation of blood pressure on standing did not change. The impairment of a comprehensive evaluation score (from 2.5 +/- 1.7 to 3.0 +/- 1.5; p < 0.05) also confirmed the gradual deterioration of autonomic function over the study period.

[ACE inhibitors and vagal activity: the effect of captopril and lisinopril on cardiovascular reflexes]. / ACE-inibitori e attività vagale: effetto di captopril e lisinopril su alcuni riflessi cardiovascolari.

The influence of the ACE-inhibitors captopril and lisinopril on parasympathetic activity in normotensive subjects was evaluated. Three cardiovascular tests which explored chiefly parasympathetic function (deep breathing, lying to standing and Valsalva test) were performed in 10 normotensive volunteers (mean age 26.1 years) in both basal conditions and after four days of treatment with either captopril (25 mg twice a day) or lisinopril (20 mg once a day). Mean blood pressure was not influenced by captopril, whereas it was significantly lowered with lisinopril (from 94.4 +/- 6.8 to 88.7 +/- 5.7 mmHg; p < 0.05). Neither drug interfered with heart rate or with the results of the deep breathing and Valsalva tests. The 30/15 ratio, an index of heart rate variability during the lying to standing test, significantly worsened after assumption of both captopril (from 1.37 +/- 0.18 to 1.21 +/- 0.14; p < 0.05) and lisinopril (from 1.31 +/- 0.17 to 1.20 +/- 0.11; p < 0.05). Although our subjects had a lisinopril-induced drop in blood pressure, their heart rate remained steady. This finding confirms previous studies reporting the lack of reflex tachycardia during ACE-inhibition. The slight effect of ACE-inhibitors on the results of deep breathing and Valsalva tests suggests that such drugs do not directly stimulate vagal activity; the significant decrease of the 30/15 ratio may be due to a functional impairment of the baroreflex mechanism.

[Transport and preservation of biological specimens for microbiological processing (author's transl)]. / Trasporto e conservazione dei campioni biologici per indagini microbiologiche.

Here you can read how to carry and preserve the biologic specimens literature speaks about and we found in many Italian hospitals. In particular we explain how to carry and preserve specimens of urine, stool, expectoration, pharyngeal exudate and we speak about the many problems of preserving isolated strains for long time.

[Evaluation of diabetic glycemic control in hospital and extra-hospital regimen (author's transl)]. / Valutazione del controllo del diabete insulino-dipendente in regime intra- ed extra-ospedaliero per mezzo di nuovi indici numerici del profilo glicemico giornaliero

It is suggested an evaluation of the degree of diabetic control in insulin-dependent "difficult" patient, during the period following the discharge from hospital. In 13 cases, the quality of glycemic regulation was compared in intra- and extra-hospital therapeutic regimen by means of 3 new indices of the diurnal blood sugar profile: the Mbs, delta, and Mdelta values. Mbs value describescribes the mean level of the blood sugar curve; delta indicates the amplitidue of the glycemic variability field; Mdelta reports both maximal and minimal extremes of the curve. A combination of the first two parameters proved adequate for a clinical assessment of diabetic control. In the majority of the cases, blood glucose patterns were found similar or even improve in extra-hospital conditions. The insulin dosage ordered during hospital staying was confirmed in all, but one, patients. Psychological approach is probably essential for such good results. The procedure seems to be suitable in order to establish a more correct starting point for an effective treatment of the diabetic out-patient.