ABSTRACT
BACKGROUND/AIMS: The aim of the present study was to investigate whether there are specific prognostic factors to predict the development of secondary pancreatic infection (SPI) in severe acute pancreatitis in order to perform a computed tomography-fine needle aspiration with bacteriological sampling at the right moment and confirm the diagnosis. METHODS: Twenty-five clinical and laboratory parameters were determined sequentially in 150 patients with severe acute pancreatitis (SAP) and univariate, and multivariate regression analyses were done looking for correlation with the development of SPI. RESULTS: Only APACHE II score and C-reactive protein levels were related to the development of SPI in the multivariate analysis. A regression equation was designed using these two parameters, and empiric cut-off points defined the subgroup of patients at high risk of developing secondary pancreatic infection. CONCLUSION: The results showed that it is possible to predict SPI during SAP allowing bacteriological confirmation and early treatment of this severe condition.
Subject(s)
APACHE , Abscess/diagnosis , Bacterial Infections/diagnosis , C-Reactive Protein/analysis , Pancreatitis/diagnosis , Acute Disease , Adolescent , Adult , Aged , Aged, 80 and over , Analysis of Variance , Bacterial Infections/mortality , Biopsy, Needle , Cholangiopancreatography, Endoscopic Retrograde , Female , Humans , Male , Middle Aged , Multivariate Analysis , Pancreatitis/mortality , Pancreatitis, Acute Necrotizing/diagnosis , Prognosis , Proportional Hazards Models , Prospective Studies , Recurrence , Regression Analysis , Risk Assessment , Sensitivity and Specificity , Severity of Illness Index , Survival RateABSTRACT
OBJECTIVE: Standard survival analysis methods are useful for data involving censored cases when cures do not generally occur. If the object is to study, for instance, the development of a complication in the progress of an infectious disease, some people may be cured before complications develop. In this article, we provide methods for the analysis of data when cures do occur. An example is a study of prognostic factors for pancreatic abscess in patients with pancreatitis, some of whom leave the risk set because the pancreatitis clears. DESIGN: We present methods for estimating the survival curves and comparing hazard function for two objectives: (1) the occurrence of an abscess, irrespective of whether the patients are cured or not, and (2) the occurrence of an abscess for patients who, at that stage, have not been cured. PATIENTS: We illustrate the applications of the methods using a sample of 50 patients with severe pancreatitis. RESULTS: To study the occurrence of an abscess, regardless of whether the patients are cured or not, we show that the appropriate strategy is to assign to the cured patients an infinite time to the appearance of an abscess. If the cured were considered censored at the moment the pancreatitis cleared, this would result in an overestimation of the hazard of presenting an abscess. On the other hand, if the objective is to compare the occurrence of abscess according to an exposure for patients who have not been cured, one needs to censor the cured patients at the time they are cured. CONCLUSIONS: For the analysis of survival data in the context of infectious diseases when cure is possible, it is important to use a censoring strategy that is pertinent to the specific aims of the study. Considering cures as censored at the time of cure is not always appropriate.
Subject(s)
Abdominal Abscess/etiology , Data Interpretation, Statistical , Pancreatitis/complications , Quality Assurance, Health Care , Hospitals, University , Humans , Logistic Models , Pancreatitis/diagnosis , Prognosis , Proportional Hazards Models , Risk Assessment , Spain , Survival AnalysisABSTRACT
BACKGROUND: In the present study the year experience of a multidisciplinary team (oncologic, unit for the acquired immunodeficiency syndrome, and surgery) with the use of a new method of central intravenous administration of medication such as that of subcutaneous venous reservoirs (SVR) is reviewed. METHODS: The subcutaneous injection capsules were implanted as a venous access in 150 surgical procedures in 146 patients from October 1985 to April 1991 with a total follow up of 29.190 days and a mean length of 251 days for SVR. Sixty-two percent (94 implantations) of the SVR were implanted in the out patient clinic, 20% (30 patients) were admitted for placement of the reservoir although this was only indicated in the first two years of the series, 13% (20 patients) during hospitalization for the base disease and only 4% (6 patients) were specifically admitted for surgical preparation (plasma, platelets, and others). SVR were used for chemotherapy (124 cases, 82%), repeated transfusions (6 cases, 4%) and chronic medication (acquired immunodeficiency syndrome, infections) (30 patients, 20%). Forty-two percent permitted chemotherapy administration by continual transfusion on an out patient regime. RESULTS: A series of mechanical complications (3 cases, 2%), septic (9 episodes in 7 patients, 5%) and thrombotic (8 of the catheter) (5%) and 4 of the central veins (2%) were observed. In the present series the rate of infections (5%) (0.072 episodes of bacteremia per 100 days/patient) and thrombosis (3%) was very low due to a strict protocol of maintenance and control by the medical team and hospital staff. The need for radiologic control during surgery is emphasized although, as demonstrated in the present review, the technique of localization by a cath-finder (external detector) permits greater speed with the same security. CONCLUSIONS: The degree of patient satisfaction and the minimum incidence of serious complications in determined risk groups (neutropenia, acquired immunodeficiency syndrome) demonstrates that subcutaneous venous reservoirs (SVR) constitute an excellent method as a chronic venous access. The SVR present a lower rate of complications if compared with any historic series of external vascular catheterization.
