Post operative infection, pyrexia and perioperative antimicrobial drug use in surgical colic patients.

REASONS FOR PERFORMING STUDY: Infections are common complications in post operative colic patients. It is the impression of some surgeons that pyrexia in the early post operative period is a sign of infection and appropriate timing of perioperative antimicrobials will decrease the incidence of post operative infection. OBJECTIVE: To determine the association between 1) post operative pyrexia and development of infection and 2) perioperative antimicrobial drug use and infection rate in post operative colic patients. METHODS: Medical records of patients undergoing surgical treatment for colic were reviewed. Horses recovering from surgery and surviving >48 h were included. Data relating to case details, duration of surgery, post operative infection, peri- and post operative antimicrobial administration, presence, intensity and duration of pyrexia, were recorded. Data were analysed using standard statistical methods for simple comparisons between groups and by logistic regression for more complex comparisons. RESULTS: One-hundred-and-thirteen horses were included in the final analyses, 48 (43%) of which were diagnosed with a post operative infection. Duration of surgery and anaesthesia were associated with post operative infection. Eighty-five percent of horses (n = 96) exhibited pyrexia (rectal temperature >38.3°C) post operatively. Peak temperature >39.2°C, time post surgery to peak temperature >48 h and duration of pyrexia >48 h were significantly associated with infection. In a combined model, time to first pyrexic >48 h post surgery, peak temperature and time to peak >48 h were equally weighted and the model's positive predictive value for post operative infection was 72%. Timing and dose rate of preoperative antimicrobials were not associated with infection but duration of post operative antimicrobial drug use was. CONCLUSION AND CLINICAL RELEVANCE: Slight to mild pyrexia (38-39.4°C) in the early post operative period is not necessarily associated with impending bacterial infection in colic patients and the use of antimicrobials in these patients may be costly and unnecessary.

Increased diagnosis of pulmonary embolism without a corresponding decline in mortality during the CT era.

AIM: To determine the association between the increasing computed tomography (CT) use for suspected pulmonary embolism (PE) on the annual rates of PE diagnosis and mortality, using time as a surrogate for CT use. MATERIALS AND METHODS: New York State's (NYS) Statewide Planning and Research Cooperative System (SPARCS) database was used to determine the rate of PE diagnosis and mortality between 1 January 1994 and 31 December 2004. Risk factors for PE were investigated. Bivariate and multivariate analyses were performed to determine the relationships between variables. RESULTS: The study population consisted of 24,871,131 NYS patients. The number of patients with a primary diagnosis of PE nearly doubled over the study period, from 2590 in 1994 to 4920 in 2004, while total admissions remained stable. PE deaths did not vary significantly over time, from 157 in 1994 to 159 in 2004 and did not vary with the diagnoses of PE. Age-adjusted multivariate analysis did not reveal a significant association between the rates of PE diagnosis or mortality and corresponding risk factors. CONCLUSION: This study suggests that the increased use of CT in patients with suspected PE has led to an increase in the diagnosis of PE without a corresponding decline in mortality. Further evidence, using data on individual patients, is needed to determine the appropriate role of CT in evaluating patients with suspected PE.