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P N Peduzzi

Publications and source records attributed to P N Peduzzi.

10 recordsLinked to original sources
PubMed1990

Impact of encephalopathy on mortality in the sepsis syndrome. The Veterans Administration Systemic Sepsis Cooperative Study Group.

Sepsis, an important cause of hospital mortality, continues to be a diagnostic and therapeutic challenge. To define more clearly the impact of encephalopathy on the course of sepsis, the various clinical signs of sepsis, blood culture results, and mortality rates were examined in relation to mental status in septic patients. Patients were classified as having an acutely altered mental status due to sepsis (AAMS), preexisting altered mental status (PAMS), or normal mental status (NMS). Twenty-three (307/1333) percent of the study patients had an acutely altered sensorium secondary to sepsis. Patients with AAMS had a higher mortality (49%) than patients with PAMS (41%) or patients with NMS (26%) (p less than .000001). Multivariate analysis disclosed that altered mental status, hypothermia, hypotension, thrombocytopenia, and the absence of shaking chills were independent predictors of increased mortality in the sepsis syndrome. Patients with Gram-negative bacteremia (28%) were as likely to have AAMS as patients with Gram-positive bacteremia (25%) or patients with negative blood cultures (23%). In summary, alterations in mental status are common in septic patients, and are associated with significantly higher mortality.

Bacterial Infections↗
PubMed1988

Five-year changes in coronary arteries of medical and surgical patients of the Veterans Administration Randomized Study of Bypass Surgery.

Progression of coronary artery disease was evaluated after 5 years of follow-up in 119 medically and 109 surgically treated randomized patients who adhered to their assigned therapy. Progression was defined as the appearance of a new lesion (greater than or equal to 50% stenosis) or worsening of a preexisting lesion in a coronary artery. Progression occurred in 36% (97 of 268) of the arteries in medical patients, in 38% (35 of 93) of the ungrafted arteries in surgical patients, in 74% (72 of 97) of the arteries with patent grafts at 5 years, and in 63% (29 of 46) of the arteries with closed grafts. After adjustment for the vessel system and the severity of disease at baseline, the risk of progression was three to six times higher in grafted arteries than in ungrafted arteries (p less than 0.01). For grafted arteries, the risk of progression was twice as high in arteries with patent grafts compared with those with closed grafts (p = 0.14). The majority (78%) of the progression in grafted arteries was to 100% occlusion. Proximal and distal progression rates in arteries with patent grafts were 74% and 11%, respectively. In the majority of arteries with closed grafts that progressed, the site of progression could not be determined. Regardless of treatment, the risk of progression was two times higher in the right coronary artery than in the left anterior descending or circumflex arteries. Progression risk was also twice as high in arteries with moderate disease at baseline compared with those with minimal or severe disease.

Coronary Angiography↗
PubMed1986

Quality control for cardiac surgery in the Veterans Administration.

The volume of cardiac surgical procedures and the 30-day mortality associated with them were reviewed for the total experience of 72 Veterans Administration medical centers over a 10-year period (1975 to 1984). The total number of cardiopulmonary bypass operations increased from 3,074 in 1975 to 6,455 in 1984, whereas operative mortality declined from 8.3 to 4.7%. Operative mortality associated with isolated valve replacement operations declined from 10.9 to 5.9%. Aortocoronary vein bypass operations, which increased in number from 1,679 to 4,988 over the 10-year period, were associated with an operative mortality of 4.7% in 1975 and 3.6% in 1984. The extent of the patient's disease accounted for most of the operative mortality, but problems related to the adequacy of myocardial protection and the surgical technique were also important factors. These data were compared with similar comprehensive statistics compiled by the New York State Department of Health over a five-year period (1979-1983). Operative mortality rates were quite similar for aortocoronary bypass procedures, mitral valve replacements, and total cardiac operations. However, operative mortality for aortic valve procedures was higher among the Veterans Administration hospitals. In the future, if operative risk factors are clearly defined, a more meaningful comparison of operative mortality among ongoing reviews, such as those being carried out by the Veterans Administration and by New York State, could be used to establish standards of performance for cardiac surgery.

Aortic Valve↗
PubMed1985

Anatomical relationships between type II pneumonocytes and alveolar septal gaps in the human lung.

This report describes a relationship between type II pneumonocytes and breaks in continuity in the alveolar septum of the human lung. Breaks in continuity of the septum are defined as gaps in the connective tissue matrix of the alveolar septum, with or without discontinuity of the accompanying alveolar epithelium. Septal connective tissue gaps accompanied by epithelial discontinuity are recognized as interalveolar pores of Kohn. When the discontinuity is confined to the connective tissue matrix, epithelial continuity may be maintained by either a single or a double layer of type I epithelium, by a type II cell, or by both type I and type II epithelial cells. Alveolar septal gaps were studied by electron microscopy on random sections in 26 adult human lung specimens and by serially sectioning and montaging the entire circumference of one alveolus to a depth of 103 microns (approximately one-half a normal alveolus) from one of the specimens. Fixation was by way of the airways in most specimens, but by vascular perfusion in the serially sectioned specimen and in seven others. In lungs studied by random sections, we found that the incidence of septal connective tissue gaps with epithelial continuity per specimen correlated with the incidence of pores (r = .468, P less than .016), and also with the incidence of type II cells (r = .422, P less than .025) in the specimen. Five percent of all type II cells observed in the random sections in the 26 specimens (103/1,955) occupied septal gaps, and 2.5% (49/1,955) were located at the rim of a pore. In contrast, in the single serially sectioned montaged alveolus, 69% of all type II cells occupied some type of septal gap, with 24% of all type II cells forming part of the rim of a pore. Over half of all pores in this alveolus were associated with a type II cell. We concluded that a relationship between the incidence of type II cells and gaps in the alveolar septum could be demonstrated on random sections in normal human lungs, which was much more obvious in a single serially sectioned hemialveolus. Serial section techniques of whole alveoli may be necessary to establish relationships that may not be apparent on random sections and that require the study of whole cells in continuity with their environment in order to be identified. The findings may be significant in suggesting a possible role of the type II cell in alveolar septal repair.

Adult↗
PubMed1983

Upper and lower bounds for correlations in 2 X 2 tables--revisited.

The correlation coefficient (r) between two dichotomous variables requires a different interpretation from that of the customary correlation between normally distributed continuous variables, since perfect correlation is usually not +1 or -1. The maximum and minimum possible correlations between two dichotomous variables depend on the marginal distributions. An example using data on smoking and lung cancer illustrates that what appears to be a small correlation in the usual sense may in fact be quite large in relation to the maximum possible. Similarly, the interpretation of R2 as the proportion of variance of the dependent variable that is explained by the independent variable(s) is subject to the same consideration. This paper describes the calculation of the upper and lower limits of r for two dichotomous variables. The problem of interpreting R2 in linear regression and the use of R2 for variable selection in stepwise regression applied to dichotomous data are also discussed and illustrated.

Epidemiologic Methods↗
PubMed1982

Validation of a risk function to predict mortality in a VA population with coronary artery disease.

A multivariate risk function based on the Cox model was developed in the VA Study of Coronary Artery Bypass Surgery to predict the survival of patients with stable angina pectoris. The methods used in developing and evaluating the performance of the risk function (validation) are described. Performance was evaluated internally by the methods of resubstitution, half-sample replication, and jackknifing, and externally by use of an independent patient population.

Actuarial Analysis↗
PubMed1977

Incidence and mortality of perioperative myocardial infarction in patients undergoing coronary artery bypass grafting.

The incidence of perioperative myocardial infarction (MI) determined by electrocardiogram was examined in 168 consecutive patients having only coronary artery bypass grafting at Yale-New Haven Hospital from July 1974 to June 1975. The incidence of MI and its mortality were correlated with clinical, hemodynamic, anatomic, and operative factors. Perioperative MI occurred in 23% of all patients (39/168); 26 in the inferior, 11 in the anterior, and two in the anterolateral wall. Three factors appeared related to the occurrence of MI: 1) abrupt propranolol withdrawal 24 hours prior to surgery (Prop) (32%, 33/103); 2) left main coronary artery disease (LMCD) (37%, 7/19); and 3) cardiopulmonary bypass longer than 60 minutes (CPB) (23%, 30/128). To more precisely predict MI, combinations of factors were examined. The combination of LMCD and CPB was 39%, (7/18) while the absence of either yielded an incidence of only 5.1% (2/39) (P less than 0.001). The mortality of patients with MI was 15.4% (6/39) while in patients without MI the mortality was 1.6% (2/129). We conclude that the risk of perioperative MI is significantly increased by abrupt propranolol withdrawal 24 hours before surgery, left main coronary artery disease, and cardiopulmonary bypass longer than 60 minutes in patients undergoing coronary artery bypass grafting. The mortality of perioperative MI is high, despite previous reports of the benignity of perioperative myocardial infarction.

Adult↗
PubMedDate not supplied

Predictors of operative mortality for coronary bypass grafting in patients with ischemic heart disease.

Predictors for operative mortality (OM) were studied in 172 consecutive patients (pts) undergoing coronary artery grafts (CAG) for angina pectoris.Seventy eight pts had Class IV angina; of the 147 patients given propranolol, 41 were gradually withdrawn from propranolol and finally discontinued 24 hours before surgery, and 106 were abruptly withdrawn from propranolol 24 hours before CAG; 20 pts had left main coronary disease; 156 pts had cardiopulmonary bypass (CPB) time shorter than 20 minutes, and 16 pts had a CPB longer than 120 minutes.The operative mortality was 5.2% (9/172) for the entire group. Class IV angina (OM 7%), abrupt propranolol withdrawal (OM 6.6%), left main coronary artery disease (OM 25%), and CPB longer than 120 minutes (OM 50%), all significantly increased OM. These variables were interdependent, however, as many pts belonged to several predictor categories, combinations of predictors were examined, in order to more accurately predict the risk of individual pts. The combination of left main coronary artery disease and CPB longer than 120 minutes; and Class IV angina and CPB longer than 120 minutes were significantly associated with higher operative mortality.We conclude that Class IV angina, abrupt propranolol withdrawal, left main coronary artery disease and prolonged CPB are potent, interdependent predictors of OM in pts undergoing CAG. Consideration of these predictors, alone and in combination, allows effective prediction of OM for CAG in patients with stable angina pectoris.

Adult↗