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P Giomarelli

Publications and source records attributed to P Giomarelli.

At least 19 recordsLinked to original sources
PubMed2005

Pressure recording analytical method (PRAM) for measurement of cardiac output during various haemodynamic states.

BACKGROUND: Cardiac output (CO) can be measured using the pressure recording analytical method (PRAM), which is a new, less invasive technique allowing beat-by-beat stroke volume monitoring from the pressure signals recorded in femoral or radial arteries. METHODS: We investigated PRAM by comparing its cardiac output (PRAM-CO) with paired measurements obtained by electromagnetic flowmetry (EM-CO) and by standard thermodilution (ThD-CO) during various haemodynamic states in a swine model. Nine pigs were monitored with a pulmonary artery catheter and a femoral artery catheter at baseline, in a hyperdynamic state produced by administration of dobutamine and in a hypodynamic state induced by progressive exsanguination. Bland-Altman analysis was used. RESULTS: One hundred and eight paired cardiac output values over a range of EM-CO of 1.8-10.4 litre min(-1) resulted. We found close agreement between the techniques. Mean bias between EM-CO and PRAM-CO was -0.03 litre min(-1) (precision 0.58 litre min(-1)). The 95% limits of agreement were -0.61 to +0.55 litre min(-1). Similar results between ThD-CO and PRAM-CO were found. CONCLUSIONS: In a porcine model we have demonstrated accuracy of PRAM during various haemodynamic states. PRAM is a reliable tool to detect changes in cardiac output in pigs and has ability as a basic research tool.

Analysis of Variance↗
PubMed2002

Optimization of mechanical ventilation support following cardiac surgery.

BACKGROUND: Mechanical ventilation (MV) is essential in the management of patients that underwent cardiac surgery and cardiopulmonary bypass. It has been demonstrated that MV dependence is directly related to morbidity incidence and ICU length of stay, with a strong impact on economic cost. Therefore identification of measures that can reduce MV interval, may reduce the incidence of respiratory complications and length of hospitalization. The aim of this study was to identify weaning indexes and adopt a weaning algorithm in order to optimize ventilatory support after cardiac surgery. METHODS: Forty-nine patients with low and medium Higgins risk score, who underwent, between February and November 1999, elective surgery at our Institution, were enrolled in this study. All patients were randomized into 2 groups: Group I (weaning group - 24 patients), extubated with the aid of a weaning protocol, and Group II (control group - 25 patients), extubated with conservative weaning, dependent on the physician's subjective clinical judgment. All patients were successfully weaned from mechanical support. RESULTS: Intubation time was significantly lower in Group I than Group II and "Fast Track Recovery" group (p=0.05). ICU length of stay was also significantly lower in Group I (p=0.03). Analysis of weaning indexes did not show cut-off points predictive of successful weaning, except for PaO2/FiO2 ratio, which was higher in Group I (p=0.02). CONCLUSIONS: These results confirm that the use of a weaning algorithm enables the MV interval and hospital length of stay to be shortened, suggesting that it should be used in the management following cardiac surgery.

Aged↗
PubMed2000

Heparin coating of extracorporeal circuits inhibits cytokine release from mononuclear cells during cardiac operations.

PURPOSE: To evaluate whether the production of interleukin 2 (IL 2), interleukin 6 (IL 6) and interleukin 10 (IL 10) from stimulated peripheral blood mononuclear cells (PBMC) was affected by coating extracorporeal circuits in patients undergoing cardiopulmonary bypass (CPB). In addition, postoperative clinical parameters were compared between patients with heparin-coated and uncoated CPB. DESIGN: Prospective, controlled in vivo/ex vivo study. PROCEDURE: Blood samples were drawn immediately before, at the end and 24 hours after the end of CPB using either a conventional circuit (n=10) or a heparin-coated circuit (n=10) in patients undergoing CPB. Cytokine release on the supernatants of activated PBMC was detected. Cardiopulmonary parameters were measured before CPB, at ICU admission, 3 hours and 24 hours after ICU admission in both groups of patients. Statistical difference intragroups and between groups were investigated with the analysis of variance for repeated measures. RESULTS: IL 6 and IL 10 release was significantly less (p<0.05) in the heparin-coated group. No differences in clinical parameters were observed between the two groups. CONCLUSIONS: These results suggest that with the use of heparin-coated circuits there is a lower production of IL 6 and IL 10 from isolated PBMC than with uncoated circuits.

Analysis of Variance↗
PubMed1999

Interleukin 10 production in patients undergoing cardiopulmonary bypass: evidence of inhibition of Th-1-type responses.

The cardiopulmonary bypass (CPB) procedure has long been associated with a generalized immunosuppression. To understand further the cytokine-mediated regulation of the complex physiological and immunological changes induced by CPB, the authors decided to investigate whether CPB affects the release of interleukin (IL)-10, as well as other cytokines, in correlation to the inhibition of T cell responses. Using phytohaemagglutinin (PHA) as mitogen and peripheral blood mononuclear cells (PBMC) isolated from patients undergoing CPB, we investigated whether this procedure has an effect on the secretion of different patterns of cytokines (Th1- and Th2-type) and PBMC proliferation. In all patients, CPB significantly enhances IL-10 and IL-6 production in resting and PHA-stimulated PBMC. On the other hand, IL-2 production, in response to PHA, was significantly diminished. Reduced IL-2 and enhanced IL-10 production were associated with a significant decrease in PBMC proliferation. Immunosuppression was also associated to lymphopenia, while neutrophil counts were significantly enhanced. These results show that after CPB there is a transient but clear unbalanced immune response demonstrated by a differentiated production of Th1- and Th2-type cytokines. The release of different patterns of cytokines observed after CPB may be helpful in understanding and preventing the development of infectious and immune complications in surgical procedure employing CPB.

Aged↗
PubMed1999

Heparin-coated circuits for high-risk patients: a multicenter, prospective, randomized trial.

BACKGROUND: Heparin-coated circuits (HCCs) in low-risk cardiac patients who have coronary revascularization have a limited impact on postoperative outcome. In this prospective, randomized investigation, we studied high-risk patients who had cardiac operations with or without HCCs. METHODS: A total of 886 patients who had cardiac operations with cardiopulmonary bypass and at least one patient-related or procedure-related risk factor were enrolled in a multicenter study. They were randomly allocated to have cardiopulmonary bypass with Duraflo II HCCs (HCC group, n = 442) or conventional circuits (control group, n = 444). Postoperative outcome was investigated with respect to the occurrence of organ dysfunction. RESULTS: HCCs are associated with a shorter intensive care unit and postoperative hospital stay and with a lower rate of patients having a severely impaired clinical outcome (stay in intensive care unit for more than 5 days or death) (relative risk 0.66, p = 0.045). Lung dysfunction rate was significantly lower for the patients in HCC group affected by chronic obstructive pulmonary disease or who had mitral procedure (relative risk, respectively, 0.31, p = 0.018 and 0.05, p = 0.02). Renal dysfunction rate was significantly (p = 0.05) lower for diabetics in the HCC group (relative risk 0.28). CONCLUSIONS: When HCCs were used postoperative times decreased and they had a protective effect on lung and kidney function in high-risk patients.

Aged↗
PubMed1997

Reduction of oxidative stress does not affect recovery of myocardial function: warm continuous versus cold intermittent blood cardioplegia.

OBJECTIVE: To compare oxidative stress after cardiac surgery in patients treated with two different methods of myocardial protection: warm continuous versus cold intermittent blood cardioplegia. To correlate oxidative stress with postoperative myocardial dysfunction. DESIGN: Prospective, randomised, double blind, trial. SETTING: Institutional centre of cardiovascular surgery. PATIENTS: 20 patients were selected for coronary artery bypass surgery (CABG) on the following basis: stable angina, ejection fraction > 50%, double or triple vessel disease, no previous CABG or associated disease. Patients were randomised to two groups of 10 patients each. INTERVENTIONS: Patients underwent CABG with one of two different methods of myocardial protection and cardiopulmonary bypass. CBC group: intermittent cold blood antegrade-retrograde cardioplegia with moderate hypothermic cardiopulmonary bypass; WBC group: continuous warm blood antegrade-retrograde cardioplegia with mild hypothermic cardiopulmonary bypass. MAIN OUTCOME MEASURE: The index of oxidative stress used was the alteration of whole blood and plasma glutathione redox status. Samples were collected from the coronary sinus and peripheral vein before anaesthesia (T1), before aortic unclamping (T2), 15 minutes (T3), and 30 minutes (T4) after unclamping. Haemodynamic parameters were measured with thermodilution techniques. RESULTS: Oxidised glutathione and glutathione-cysteine mixed disulphide significantly increased in the coronary sinus plasma in the CBC group, and the overall redox balance of glutathione was decreased (P < 0.01) at T2-T4 versus T1, and compared with the WBC group. Comparable results were obtained for coronary sinus blood. There was no correlation between postoperative haemodynamic measurements and oxidative stress markers. CONCLUSIONS: Oxidative stress was significant in patients undergoing CABG using cold blood cardioplegia, while the warm technique minimised the effects of ischaemia. However, oxidative stress was not correlated with myocardial dysfunction following CABG.

Analysis of Variance↗
PubMed1996

Video-assisted minimally invasive coronary operations without cardiopulmonary bypass: a multicenter study.

OBJECTIVE: The need to avoid the risks associated with cardiopulmonary bypass has led to the interest in coronary operations without cardiopulmonary bypass. PATIENTS AND METHODS: From April 1994 to September 1995, 44 patients (mean age 63.3 +/- 10.0 years, range 43 to 83 years) were selected for video-assisted coronary artery bypass grafting without cardiopulmonary bypass through a small anterior thoracotomy. Mean preoperative ejection fraction was 50.7% +/- 13.4% (range 20% to 65%). Four patients had left ventricular dysfunction (ejection fraction below 35%). Thirty patients had stable angina (26 with class 3 angina) and 14 had unstable angina. One had recurrent angina (redo). In all cases a small (3.5 to 11 cm) anterior thoracotomy (43 left and one right) was performed and the harvesting of the left internal thoracic artery was video-assisted by thoracoscopy. RESULTS: The left internal thoracic artery was used in 43 cases to graft the left anterior descending coronary artery; the right thoracic mammary was used in one case to graft the right coronary artery; the radial artery was used in one case to perform a T-graft to the first diagonal and first marginal branches. We recorded one death (2.3%) and one case of postoperative low cardiac output syndrome (2.3%). Perioperative myocardial infarction occurred in two cases (4.5%). We did not record noncardiac complications (cerebrovascular complications, kidney failure, prolonged ventilatory support, or wound complications). Supraventricular and ventricular arrhythmias were never detected. CONCLUSION: According to our experience, video-assisted coronary bypass through a small anterior thoracotomy is a new promising technique that can be considered an alternative in most cases to angioplasty and complementary to conventional coronary operations.

Adult↗
PubMed1995

In vitro cytokine production and T-cell proliferation in patients undergoing cardiopulmonary by-pass.

Cardiac surgery, employing cardiopulmonary by-pass (CPB), has long been associated with a generalized immunosuppression. To further understand the complex physiological and immunological changes related to CPB, we decided to investigate whether CPB affects the immune response, with regard to T-cell activation and cytokine production. Using phytohaemagglutinin (PHA) as mitogen and peripheral blood mononuclear cells (PBMC) isolated from patients undergoing CPB, we investigated whether this procedure has any effect on interferon-gamma(IFN-gamma) and other cytokine production and/or PBMC proliferation. Comparisons were made between the responsiveness of PBMC obtained before, during and at the end of CPB. In all patients, CPB significantly reduces IFN-gamma and interleukin 2 (IL-2) production in response to PHA. On the other hand, tumour necrosis factor-alpha (TNF-alpha) production was also significantly diminished, while interleukin 6 (IL-6), interleukin 1 beta (IL-1 beta) and interleukin 8 (IL-8) release in response to PHA was not significantly affected. Reduced IFN-gamma, IL-2 and TNF-alpha production was associated with a significant decrease in PBMC proliferation. These results might be related to the mechanical damage on blood cells described during extracorporeal circulation procedures as well as the release of immunosuppressive factors during surgery. The immunosuppression observed during CPB may play an important role in the development of infectious complications after CPB.

Cardiopulmonary Bypass↗
PubMed1995

Coronary surgery without cardiopulmonary bypass.

The need to obviate the risks associated with cardiopulmonary bypass (CPB) in coronary surgery has led to an interest in coronary artery bypass grafting without CPB. From November 1994 to May 1995, 58 patients (49 males and 9 females, mean age 61.8 +/- 9.3 years, range 40-74) were selected for coronary artery bypass grafting without CPB. Three patients had left main stenosis and 6 had left ventricular dysfunction (ejection fraction < 40%). Stable angina was present in 42 patients (27 with low threshold angina) and unstable angina in 16. In 44 patients a routine median sternotomy and in 14 cases a small anterior thoracotomy were performed: in the latter the proximal harvesting of the left internal mammary artery was video-assisted by thoracoscopy. The left internal mammary artery was used in 53 cases; the saphenous vein was used in 36 cases; the radial artery was used in 4 cases; the inferior epigastric artery was used in 2 cases and the right gastroepiploic artery in 1 case. We recorded 1 death (1.7%) and 1 case of postoperative low cardiac output syndrome requiring counterpulsation (1.7%). Perioperative myocardial infarction occurred in 3 cases (5.8%). We did not record noncardiac complications (cerebrovascular, renal failure, prolonged ventilatory support over 24 hours or sternal wound complications). Supraventricular and ventricular arrhythmias were never detected. Mean intensive care unit and hospital stay were 1.1 +/- 0.5 and 5.1 +/- 1.7 days, respectively. In conclusion, according to our experience, "beating heart" coronary surgery is a new promising technique that can be considered alternative in most cases to percutaneous transluminal coronary angio and complementary to conventional coronary surgery.

Adult↗
PubMed1993

Myocardial function in early hours after coronary artery bypass grafting: comparison of two cardioplegic methods.

The theoretical advantages of retrograde blood cardioplegia combined with anterograde blood cardioplegia and warm reperfusion before aortic unclamping during coronary surgery were evaluated in 41 patients (group 2). The early postoperative myocardial function of this group was compared with that of 55 patients (group 1) in whom cold crystalloid cardioplegia was administered. The following variables were measured and analyzed by multivariate statistical analysis: heart rate, left atrial pressure, systemic arterial pressure, cardiac index, left ventricular stroke work index, ventricular function, oxygen delivery, hemoglobin, partial oxygen pressure in mixed venous blood, arteriovenous oxygen difference, carbon dioxide production per square meter, and cardiac isoenzyme of creatine-kinase. The myocardial function improved progressively and cardiac enzymatic release was low for both groups 9 hours after admission to the intensive care unit. However, group 2 had significantly higher oxygen delivery, carbon dioxide production per square meter, cardiac index, left ventricular stroke work index, and ventricular function and significantly lower left atrial pressure and mean systemic arterial pressure than that of group 1. The best separation of group 2 from group 1 occurred at the ninth hour, with a probability of correct recognition of 92.1%.

Blood Pressure↗
PubMed1991

[Cardiogenic shock].

Explore the source record for details and available documents.

Heart-Assist Devices↗
PubMed1990

Lipid peroxidation and lung ultrastructural changes in an experimental model of leukocyte-mediated pulmonary injury.

The aim of this study was to study ultrastructural changes and lipid peroxidation in rabbits lung after massive complement activation and leukocyte aggregation. A prolonged and massive leukocyte activation was induced by intraperitoneal inoculation of zymosan suspected in paraffin. Fifteen animals (group 3) were given 0.6 g/kg of zymosan, 22 animals (group 2) received 1 g/kg, and 11 rabbits (group 1) were treated with paraffin alone and served as controls. An acute mortality rate of 40% was observed in group 3 and of 68% in group 2. Surviving animals were studied for 10 days. In these animals a marked decrease in circulating granulocytes and a progressive decline in arterial PO2 were recorded (PO2 on day 10 in group 2 animals was 51.94 +/- 4.26, p less than 0.01). Microscopic and ultrastructural evaluation revealed sequestration of granulocytes in the pulmonary microvasculature. Studies of lung homogenates demonstrated increased levels of lipid peroxide derivative malondialdehyde (group 2 rabbits, 1624 +/- 638; group 1, 795 +/- 57 pm/mg pt, p less than .001) and decreased levels of the tissue antioxidant alpha-tocopherol. The results of this study are compatible with the hypothesis of leukocyte-mediated injury through production of oxygen radicals.

Animals↗