Biomedical subjects

Manuel Fontes

Publications and source records attributed to Manuel Fontes.

4 recordsLinked to original sources

PubMed2005

Hormone replacement therapy is safe in women undergoing coronary artery bypass grafting.

In postmenopausal women, hormone replacement therapy (HRT) does not substantially reduce the incidence of cardiovascular disease and may produce a short-term increase in risk. Therefore, we investigated whether HRT increased risk in patients with severe coronary artery disease necessitating surgery We prospectively studied 4,782 patients undergoing coronary artery bypass grafting at 70 centers in 17 countries from November 1996 through June 2000. Patients were selected using a systematic sampling technique. Mortality, major morbidity, and transfusion requirements were compared among 3 groups: men (n=3,840), women receiving HRT (n= 144), and women not receiving HRT (n=798). Women actively receiving HRT, compared with women not receiving HRT or with men, were at no greater risk of developing the following fatal or non-fatal complications: death (2.8% vs 4.4% vs 2.8%, respectively; P=0.05), myocardial infarction (6.3% vs 7.0% vs 7.7%; P=0.67), central nervous system complication (2.1% vs 2.8% vs 2.9%; P=0.85), or renal dysfunction (0.7% vs 5.3% vs 4.8%; P=0.06). Incidence of postoperative congestive heart failure was significantly lower in men (7.7%) than in women receiving HRT (12.5%; P=0.04) and in women without HRT (12.8%; P <0.0001). Fewer men (61%) needed red blood cell transfusion than did women receiving HRT (79%) and women without HRT (88%) (P <0.0001 compared with both other groups). However, the need for fresh frozen plasma transfusions was significantly less in women receiving HRT (16%) than in women not receiving HRT (25%; P=0.01). We conclude that HRT administration before coronary artery bypass grafting does not increase women's risk of any adverse outcome.

Aged↗

PubMed2003

Neutrophil CD11b upregulation during cardiopulmonary bypass is associated with postoperative renal injury.

BACKGROUND: Renal injury remains a persistent complication of cardiopulmonary bypass (CPB) that, when sufficient to require dialysis, increases mortality eight-fold. The high prevalence of renal failure in sepsis and adult respiratory distress syndrome has been linked to the systemic inflammatory response associated with those disorders. We hypothesized that components of the inflammatory response to CPB may similarly contribute to post-CPB acute renal injury. METHODS: Markers of leukocyte and platelet activation peri-CPB were measured in 75 patients undergoing cardiac operation with CPB and were correlated with acute renal injury, defined as an increase (> or = 50%) in peak serum creatinine post-CPB. RESULTS: Eleven patients sustained post-CPB acute renal injury. This subset of patients demonstrated significantly greater increases in neutrophil CD11b density (p = 0.01), as well as higher total neutrophil counts (p = 0.045), compared with patients with preserved renal function. Hemodynamic instability sufficient to require postoperative hemodynamic support also predicted an increased risk of acute renal injury. However, neutrophil CD11b upregulation did not correlate with this or any other clinical variables associated with renal risk, suggesting that this marker of the neutrophil inflammatory response may independently predict renal injury. By contrast other inflammatory markers, neutrophil myeloperoxidase levels, monocyte CD11b, base line C-reactive protein, and platelet CD62P expression did not differ between the two patient groups. CONCLUSIONS: Upregulation of the neutrophil adhesion receptor CD11b and high circulating neutrophil numbers are associated with acute renal injury after CPB, suggesting a contribution by activated neutrophils to the pathophysiology of this complication.

Acute Kidney Injury↗

PubMed2002

Platelet PlA2 polymorphism and platelet activation are associated with increased troponin I release after cardiopulmonary bypass.

BACKGROUND: The PlA2 polymorphism of platelet glycoprotein IIIa has been identified as a prothrombotic risk factor in a number of cardiovascular settings. The aim of this study was to determine whether the PlA2 polymorphism of platelet glycoprotein IIIa and degree of platelet activation were associated with more severe myocardial injury as indicated by troponin I release following cardiopulmonary bypass. METHODS: The PlA2 genotype was determined in 66 patients undergoing elective coronary artery bypass grafting requiring cardiopulmonary bypass. Troponin I concentrations and the percentage of circulating, activated (CD62P+) platelets were measured at predetermined intervals perioperatively. RESULTS: Forty-six patients were Pl(A1,A1), and 20 were Pl(A1,A2) or Pl(A2,A2). Patients with at least one PlA2 allele had significantly greater postoperative troponin I concentrations than PlA1 homozygotes (P = 0.006, analysis of variance). Peak troponin I concentrations also correlated significantly with the increase in circulating, activated platelets (P = 0.02, Spearman rank correlation). CONCLUSIONS: The PlA2 allele of platelet glycoprotein IIIa is associated with higher troponin I concentrations following cardiopulmonary bypass surgery, suggesting that this platelet polymorphism contributes to perioperative myocardial injury.

Adult↗

PubMed2002

Progress in mechanical ventilation.

Mechanical ventilation is a life-supporting process employed in the management of respiratory failure. Over the years, our understanding of the pathophysiology of lung injury has greatly improved, and has aided the technological development of ventilatory modes that are more patient 'sensitive' and less traumatizing to the lungs. This review will discuss the fundamental modes of mechanical ventilation, and present current concepts regarding patient-ventilator interaction that either promote lung healing and weaning from positive pressure ventilation or delay recovery because of the injudicious use of ventilatory modalities that are incapable of meeting the ventilatory demands of the patient on a breath-by-breath basis. In addition, the current strategy for mechanical ventilation in acute lung injury and acute respiratory distress syndrome will be summarized.

Journal Article↗