Extensive fever workup produces low yield in determining infectious etiology

Early post-operative fever after colorectal surgery in infants is common and rarely associated with infection

PURPOSE

Early post-operative fever (< 48 h) is common in adults and children and seldom indicative of an infection. Guidance to limit excessive evaluation in adults is well-characterized but similar studies for the pediatric population is scarce. This study was performed to better clarify which infants should undergo investigation for post-operative fever after colorectal reconstructive surgical procedures.

METHODS

We performed a retrospective chart review of all infants under one year of age who underwent elective reconstruction for anorectal malformations (ARM) and Hirschsprung Disease (HD) between June 2018 and April 2020 at a single institution. Patient and perioperative characteristics were analyzed to evaluate for possible factors associated with infection.

RESULTS

Sixty-eight infants met study criteria - 38 (55.9%) had HD and 30 (44.1%) had ARM. Twenty-two infants (32.4%) had early post-operative fever. A definitive infectious cause was identified in only two infants. The presence of a colostomy pre-operatively and longer operative times were associated with increased risk of post-operative fever (62.5% vs. 22.7% and 175 min vs. 150 min respectively, p < 0.05).

CONCLUSION

Early post-operative fever in infants after colorectal surgery is common and rarely associated with an infection. Further research is needed to determine which infants require further work-up and which can be safely observed.

An Exploratory and Qualitative Analysis of Self-Reported Evaluations for Fever

Background: Despite the high prevalence of post-operative fever, a variety of approaches are taken as to the components of a fever evaluation, when it should be undertaken, and when empiric antibiotic agents should be started. Hypothesis: There is a lack of consensus surrounding many common components of a post-operative fever evaluation. Patients and Methods: The Surgical Infection Society membership was surveyed to determine practices surrounding evaluation of post-operative fever. Eight scenarios were posed in febrile (38.5°C), post-operative general surgery or trauma patients, with 19 possible components of work-up (physical examination, complete blood count [CBC], fungal biomarkers, lactate and procalcitonin [PCT] concentrations, cultures, imaging) and management (antibiotic agents). Each scenario was then re-considered for intensive care unit (ICU) patients (intubated/unstable hemodynamics). Agreement on a parameter (<1/4 or >3/4 of respondents) achieved consensus, positive or negative. Parameters between had equipoise; α was set at 0.05. Results: Among the examined scenarios, only CBC and physical examination received positive consensus across most scenarios. Blood/urine cultures, imaging, lactate, inflammatory biomarkers, and the empiric administration of antibiotic agents did not reach consensus; support was variable depending on the clinical scenario, illness severity, and the individual preferences of the answering clinician. The qualitative portion of the survey identified "fever threshold and duration," "clinical suspicion," and "physiologic manifestation" as the most important factors for deciding about the initiation of a fever evaluation and the potential empiric administration of antibiotic agents. Conclusions: There is consensus only for physical and examination routine laboratory work when initiating the evaluation of febrile post-operative patients. However, there are multiple components of a fever evaluation that individual respondents would select depending on the clinical scenario and severity of illness. Parameters demonstrating equipoise are potential candidates for formal guidance or pragmatic prospective trials.

The impact of antimicrobial management by clinical pharmacists in obstetrics and gynecology on antimicrobial indicators, bacterial resistance and drug costs from 2011 to 2021 in China

Objectives

The goal of our study is to analyze the effectiveness and role of clinical pharmacists in antibiotic management through retrospective research from 2011 to 2021, depending on the current scenario of the antibiotic application in China.

Methods

We formed a team of pharmacists to carry out multifaceted intervention measures, such as forming a working group, developing a plan, establishing management rules via the pre-trial system, prescription comments, collaborating with the administrative department, implementing training and publicity, and so on. Antibiotic use was studied, bacterial drug resistance was determined, and antibiotic costs were computed.

Results

The pharmacist intervention and rectification of inappropriate antibacterial drug orders considerably enhanced the rational use rate of antibiotics and reduced the cost of antibiotics. Antibiotic use in clean surgery decreased from 90.22% to 11.14%, the use rate of antibiotics decreased from 63.82% to 30.26%, and antibiotic use intensity decreased from 42.75DDDs to 30.04DDDs. The types, timing, and course of antibacterials used in wards were all improved to varying degrees. Bacterial drug resistance improved noticeably, with resistance of Escherichia coli to cephalosporins, ciprofloxacin and carbapenems decreased in varying degrees. The use of antibacterial drugs has decreased significantly.

Conclusions

It is feasible and effective for pharmacists in gynecology and obstetrics to control antibiotic use, which plays a positive role in promoting the safe, effective, and cost-effective use of antibiotics and serves as a valuable reference for the antibiotic management.

Characteristics and risk factors of fever after total joint arthroplasty: a single-center retrospective study

Background

Postoperative fever (POF) is a common problem after total joint arthroplasty (TJA). The goal of this research is to analyze the characteristics and risk factors of fever following TJA.

Methods

We retrospectively investigated 2482 patients who had primary total knee arthroplasty (TKA) or total hip arthroplasty (THA) surgery at our institution between January 2020 and December 2020. Those patients were divided into TKA group and THA group. The patients' axillary temperatures were measured. POF was defined as a body temperature greater than 38 °C. Then patients in the TKA and THA groups were respectively divided into afebrile group and febrile group based on their body temperatures. Temperature changing characteristics of the patients in the febrile group were analyzed and recorded. According to the number of patients in the febrile group, we randomly selected a corresponding number of patients from the afebrile group at a ratio of 1:2 to establish a control group. Gender, hypertension, diabetes, anesthesia, surgical time, and some laboratory data were analyzed between the febrile group and the afebrile group.

Results

Three percent of TKA patients (N = 45) had febrile, and in the febrile group of TKA group, 38% (N = 17) had fever and maximum body temperature on postoperative day 2(POD2). Six percent of THA patients (N = 46) had fever, and in the febrile group of THA group, 65% (N = 30) of the patients had fever and maximum body temperature on POD1. In TKA group, compared with afebrile group, febrile group has higher C-reactive protein (mg/L) (CRP) after surgery. In THA group, compared with the afebrile group, the patients in the febrile group had larger fall in hemoglobin (g/L), and higher C-reactive protein (mg/L) (CRP) after surgery, so there were statistically significant differences between the two groups (P < 0.05).

Conclusion

The POF rate of TKA is 3%, and the first fever and maximum body temperature most commonly appear on the POD2. THA has a 6% POF rate, and the first fever and the maximum body temperature most commonly appear on the POD1. In both groups, high C-reactive protein is a risk factor for postoperative fever. In addition, the fall in hemoglobin is also related to postoperative fever in the THA group.

Association Between Postoperative Fever and Readmission Rates in Lumbar Fusion Patients

STUDY DESIGN

This is a retrospective observational study.

OBJECTIVE

This study evaluates the impact of postoperative fever on the rate of readmission among lumbar fusion patients.

SUMMARY OF BACKGROUND DATA

Postoperative fever is a common event across surgical specialties that often triggers an extensive work-up that can significantly increase hospital costs and length of stay, although the results are usually negative for infection. There is a paucity of literature studying postoperative fever in lumbar fusion patients.

MATERIALS AND METHODS

A retrospective chart review of all the patients who underwent elective posterior lumbar spinal fusion from January, 2018 to November, 2018 was conducted. Fever was defined as a temperature >100.4ºF. Patients were categorized into 4 groups based on their highest recorded temperature postoperatively. The association between demographic variables, tests ordered per patient, length of stay, and readmission rates per group were analyzed using a t test, and 1-way analysis of variance for continuous outcomes, and the Fisher exact test for categorical variables.

RESULTS

Of 107 patients, 58% had no fever recorded, 17.75% had temperatures between 100.5 and 100.90ºF, 18.69% temperatures between 101 and 101.90ºF, and 4.67% of patients temperatures equal or higher than 102.0ºF. The number of tests per patient increase with the range of temperatures analyzed (P<0.01), but the rate of readmission of all the 4 groups are not significantly different (0.107). There is no significant difference in the number of febrile episodes per day between patients who were and who were not readmitted (0.209).

CONCLUSIONS

A diagnostic testing policy guided by clinician assessment of symptoms and physical exam may limit unnecessary testing and reduce hospital length of stay and cost without sacrificing patient safety.

Clinical Predictors of Positive Postoperative Blood Cultures

OBJECTIVE

To define clinical features of surgical patients in whom postoperative blood cultures are likely to identify pathogens.

BACKGROUND

Bacteremia is a worrisome postoperative complication and blood cultures (BCx) are routinely used for evaluation of postoperative bacteremia, but are costly and not always diagnostic. Better methods are needed to select patients in whom BCx identify pathogens.

METHODS

We reviewed records of patients ≥18 years old with BCx drawn ≤10 days after surgery in 2013 seeking independent predictors of positive cultures by simple and multiple logistic regression models with statistical significance at α = 0.05.

RESULTS

Of 1804 BCx, excluding contaminants yielded 1780 cultures among 746 patients for analysis. The yield was low, with only 4% identifying potential pathogens. Positive BCx were most common after cardiac, ear/nose/throat, obstetric, and urologic procedures [odds ratio (OR) =10.3, P < 0.001 vs low-yield procedures: eg, gynecologic, neurosurgical, plastic surgical, podiatric, transplant]. Cultures more often grew pathogens when drawn in association with higher peak temperature (Tmax, P = 0.001) and longer interval from procedure to Tmax (P = 0.001). Antibiotic therapy at time of culture reduced yield (2.9% with vs 5.5% without antibiotics, P = 0.007). Multivariable logistic regression analysis found antibiotics at culture, procedure specialty, Tmax, and postoperative timing of Tmax were associated with blood culture results.

CONCLUSIONS

Ordering blood cultures based on fever or another single predictor inconsistently identifies pathogens. Our dataset, the largest available, identify clinical predictors in the first 10 postoperative days to guide identification of patients with bacteremia.

Early postoperative fever workup in children: utilization and utility

BACKGROUND

Early postoperative fever is common. Adult data indicate that workup is unnecessary in the early postoperative period, but comparable data in children is limited. The objectives are to determine the incidence of fever and the utilization and yield of tests ordered in children.

METHODS

Single-institution, retrospective analysis of surgical patients undergoing an elective inpatient/observational surgery between 2011 and 2015 was performed. Early fever was defined >38.0°C within two days post-procedure. Encounters were queried for all blood cultures (BC), urinalysis (UA), urine cultures (UC), chest radiographs (CXR), and respiratory viral panels (RVP) obtained.

RESULTS

We identified 6943 patients, of whom 30.6% developed fever. UA was positive in 19.8% of patients tested. UC was positive in 15.7% of patients and 92.0% had a urinary catheter during surgery. BC was positive in 0.69% of patients, all with a central venous catheter. CXRs were considered infectious in 3.0% of patients tested. Patients with PICU stay and/or fever ≥38.9°C were more likely to undergo BC and UC, but no more likely to have a positive result compared those without PICU stay and/or fever <38.9°.

CONCLUSION

Early postoperative fever is common in pediatric surgical populations and rarely associated with an infectious source. Workup should be applied selectively.

LEVEL OF EVIDENCE

Level IV.

Postoperative Fever Evaluation Following Lumbar Fusion Procedures

Objective

This study aimed to determine the incidence of postoperative fever, the workup conducted for postoperative fever, the rate of subsequent fever-related diagnoses or complications, and the risk factors associated with fever following lumbar fusion.

Methods

A retrospective review of patients undergoing lumbar fusion was performed. For patients in whom fever (≥38.6°C) was documented, charts were reviewed for any fever workup or diagnosis. Multivariate regression was used to identify independent risk factors for the development of postoperative fever.

Results

A total of 868 patients met the inclusion criteria, of whom 105 exhibited at least 1 episode of fever during hospitalization. The first documentation of fever occurred during the first 24 hours in 43.8% of cases, during postoperative hours 24–48 in 53.3%, and later than 48 hours postoperatively in 2.9%. At least 1 component of a fever workup was conducted in 47 of the 105 patients who had fever, resulting in fever-associated diagnoses in 4 patients prior to discharge. Three patients who had fever during the inpatient stay developed complications after discharge. On multivariate analysis, operations longer than 150 minutes (relative risk [RR], 1.66; p=0.015) and narcotic consumption greater than 85 oral morphine equivalents on postoperative day 0 (RR, 1.53; p=0.038) were independently associated with an increased risk of developing postoperative fever.

Conclusion

The results of this study suggest that inpatient fever occurred in roughly 1 in 8 patients following lumbar fusion surgery. In most cases where a fever workup was performed, no cause of fever was detected. Longer operative time and increased early postoperative narcotic use may increase the risk of developing postoperative fever.

Postoperative Nonpathologic Fever After Spinal Surgery: Incidence and Risk Factor Analysis

BACKGROUND

Although there are many postoperative febrile causes, surgical-site infection has always been considered as one of the major causes, but it should be excluded; we encountered many patients who showed delayed postoperative fever that was not related to wound infection after spinal surgery. We aimed to determine the incidence of delayed postoperative fever and its characteristics after spinal surgery, and to analyze the causal factors.

METHODS

A total of 250 patients who underwent any type of spinal surgery were analyzed. We determined febrile patients as those who did not show any fever until postoperative day 3, and those who showed a fever with an ear temperature of greater than 37.8°C at 4 days after surgery. We collected patient data including age, sex, coexistence of diabetes mellitus or hypertension, smoking history, location of surgical lesion (e.g., cervical, thoracic, lumbar spine), type of surgery, surgical approach, diagnosis, surgical level, presence of revision surgery, operative time, duration of administration of prophylactic antibiotics, and the presence of transfusion during the perioperative period, with a chart review.

RESULTS

There were 33 febrile patients and 217 afebrile patients. Multivariate logistic regression showed that surgical approach (i.e., posterior approach with anterior body removal and mesh graft insertion), trauma and tumor surgery compared with degenerative disease, and long duration of surgery were statistically significant risk factors for postoperative nonpathologic fever.

CONCLUSIONS

We suggest that most spinal surgeons should be aware that postoperative fever can be common without a wound infection, despite its appearance during the late acute or subacute period.

Routine Workup of Postoperative Pyrexia Following Total Joint Arthroplasty Is Only Necessary in Select Circumstances

BACKGROUND

It is unclear when routine workup of postoperative pyrexia (POP) following total joint arthroplasty (TJA) should be performed.

METHODS

A retrospective electronic database search was conducted on 25,558 consecutive patients undergoing primary or revision TJA between June 2001 and June 2013. We identified patient demographics, procedure type, characteristics of feverish patients, and febrile complications. The estimated costs for chest x-ray (CXR), urinalysis, urine culture, and blood culture were investigated.

RESULTS

POP occurred in 46% of TJAs. A total of 11,589 separate workups were performed in 90.5% of POP patients, of which 2.4% were positive. Urinalysis, urine culture, blood culture, and CXR were positive in 38.7%, 9.5%, 7.0%, and 0.2%, respectively. Febrile complications occurred in 4.5% and the infectious complications rate was 2.0%. The positive rate of fever workups was significantly higher in patients with the first POP occurring after postoperative day 3, POP > 102°F, multiple fever spikes, and patients undergoing revision TJA. Multivariate logistic regression revealed that the time of first POP, the maximum temperature, multiple fever spikes, and revision TJA were independent predictors of febrile complications. The estimated cost for 11,319 negative workups in patients with POP was $4,636,976.80, with CXR costing $4,613,182.00.

CONCLUSION

Selective workup of POP following TJA should be performed in patients with higher temperatures, fever occurring after postoperative day 3, those with multiple fever spikes, and those undergoing revision TJA. CXR with an extremely low positive rate should not routinely be ordered.

Infection Prevention and Evaluation of Fever After Laparoscopic Hysterectomy

BACKGROUND

Surgical site infection (SSI) is a common complication of hysterectomy. Minimally invasive hysterectomy has lower infection rates than abdominal hysterectomy. The lower SSI rates reflect the role and benefit in infection control of having minimal incisions, rather than a large anterior abdominal wall incision. Despite the lower rates, SSI after laparoscopic hysterectomy is not uncommon.In this article, we review pre-, intra-, and postoperative risk factors for infection. Rates of postoperative fever after laparoscopic hysterectomy and when evaluation for infection is warranted in a febrile patient are also reviewed.

DATABASE

PubMed was searched for English-only articles using National Library of Medicine Medical Subject Headings(MESH) terms and keywords including but not limited to "postoperative," "surgical site," "infection," "fever," "laparoscopic," "laparoscopy," and "hysterectomy."

CONCLUSIONS

Reducing hospital-acquired infections such as SSI is one of the more effective ways of improving patient safety. Knowledge and understanding of risk factors for infection following laparoscopic hysterectomy enable the gynecologic surgeon or hospital to implement targeted preventive measures.

Fever after maxillofacial surgery: a critical review

PURPOSE

The aim of this paper is to review the pathophysiology of thermoregulation mechanism, various causes of fever after maxillofacial surgery and the different treatment protocols advised in the literature.

DISCUSSION

Fever is one of the most common complaints after major surgery and is also considered to be an important clinical sign which indicates developing pathology that may go unnoticed by the clinician during post operative period. Several factors are responsible for fever after the maxillofacial surgery, inflammation and infection being the commonest. However, other rare causes such as drug allergy, dehydration, malignancy and endocrinological disorders, etc. should be ruled out prior to any definite diagnosis and initiate the treatment. Proper history and clinical examination is an essential tool to predict the causative factors for fever. Common cooling methods like tepid sponging are usually effective alone or in conjunction with analgesics to reduce the temperature.

CONCLUSION

Fever is a common postoperative complaint and should not be underestimated as it may indicate a more serious underlying pathology. A specific guideline towards the management of such patients is necessary in every hospital setting to ensure optimal care towards the patients during post operative period.

Incidence, risk factors, and diagnostic evaluation of postoperative fever in an orthopaedic trauma population

OBJECTIVES

To determine the incidence of positive diagnostic evaluations during the management of postoperatively febrile orthopaedic trauma patients. A secondary objective was to describe the incidence and risk factors for postoperative fever.

DESIGN

Retrospective study.

SETTING

The orthopaedic trauma service at a tertiary referral hospital.

PATIENTS

Postoperatively febrile orthopaedic trauma patients admitted from 2005 to 2008.

MAIN OUTCOME MEASURES

In patients who developed postoperative fever (oral temperature ≥38.5ºC), records were reviewed to determine whether urinalysis, urine cultures, blood cultures, chest radiographs, or wound cultures were performed and subsequent results were recorded. Patient demographics including sex, age, and medical comorbidities were also noted.

RESULTS

A total of 106 subjects (18%) developed a postoperative fever, with a mean temperature of 38.8 ± 0.3ºC (range, 38.5-40.0ºC). Overall, 135 diagnostic tests were ordered with 14 being positive (10%). Yields per individual test were as follows: urinalyses, 7 of 34 (21%); urine cultures, 4 of 38 (11%); chest radiograph, 2 of 23 (9%); blood cultures, 1 of 38 (3%); and wound cultures, 0 of 2 (0%). Patients investigated on postoperative day 6 or later had a greater incidence of positive diagnostic evaluations (40%) than patients investigated on postoperative days 0-5 (16%). The single positive blood culture was found on postoperative day 16.

CONCLUSIONS

Postoperative fever is common among orthopaedic trauma patients. Diagnostic evaluations have a low-positive yield, particularly in the early postoperative period. In the later postoperative period, physicians should be more suspicious for an infective source of fever because a traumatic inflammatory etiology of fever is less likely.

Blood cultures for evaluation of early postoperative fever after femoral neck fracture surgery

PURPOSE

To evaluate the utility of blood cultures in the assessment of early postoperative fever in hip fracture patients with no other indicators of sepsis.

METHODS

101 blood cultures were drawn on postoperative days 0 to 5 to investigate 84 febrile episodes in 31 women and 30 men (mean age, 80 years) whose body temperature measured via the tympanic route was ≥ 38 ºC. Culture results of these 61 patients were divided into culture-positive and culture-negative groups for comparison.

RESULTS

Of the 101 blood cultures, only 2 were positive: one was obtained 5 days after dynamic hip screw fixation, and the other 4 days after hemiarthroplasty. Both blood cultures grew coagulase-negative staphylococcal species, which were deemed to be skin contaminants not requiring change of patient management. 44 of these patients were treated with oral or intravenous antibiotics for a period of time.

CONCLUSION

The risk of bacteraemia in patients with postoperative fever but no other symptoms of infection is low. Routine procurement of blood cultures in such patients is ineffective and of limited utility.

Enhancing the fever workup utilizing a multi-technique modeling approach to diagnose infections more accurately

BACKGROUND

Differentiation between infectious and non-infectious etiologies of the systemic inflammatory response syndrome (SIRS) in trauma patients remains elusive. We hypothesized that mathematical modeling in combination with computerized clinical decision support would assist with this differentiation. The purpose of this study was to determine the capability of various mathematical modeling techniques to predict infectious complications in critically ill trauma patients and compare the performance of these models with a standard fever workup practice (identifying infections on the basis of fever or leukocytosis).

METHODS

An 18-mo retrospective database was created using information collected daily from critically ill trauma patients admitted to an academic surgical and trauma intensive care unit. Two hundred forty-three non-infected patient-days were chosen randomly to combine with the 243 infected-days, which created a modeling sample of 486 patient-days. Utilizing ten variables known to be associated with infectious complications, decision trees, neural networks, and logistic regression analysis models were created to predict the presence of urinary tract infections (UTIs), bacteremia, and respiratory tract infections (RTIs). The data sample was split into a 70% training set and a 30% testing set. Models were compared by calculating sensitivity, specificity, positive predictive value, negative predictive value, overall accuracy, and discrimination.

RESULTS

Decision trees had the best modeling performance, with a sensitivity of 83%, an accuracy of 82%, and a discrimination of 0.91 for identifying infections. Both neural networks and decision trees outperformed logistic regression analysis. A second analysis was performed utilizing the same 243 infected days and only those non-infected patient-days associated with negative microbiologic cultures (n = 236). Decision trees again had the best modeling performance for infection identification, with a sensitivity of 79%, an accuracy of 83%, and a discrimination of 0.87.

CONCLUSION

The use of mathematical modeling techniques beyond logistic regression can improve the robustness and accuracy of predicting infections in critically ill trauma patients. Decision tree analysis appears to have the best potential to use in assisting physicians in differentiating infectious from non-infectious SIRS.

Postoperative Fever Discharge Guidelines Increase Hospital Charges Associated With Spine Surgery

BACKGROUND:

Postoperative fever is a common sequel of spine surgery. In the presence of rigid nationally mandated clinical guidelines, fever management may consume more health care resources than is reasonably appropriate.

OBJECTIVE:

To study the relationship between postoperative fever, infection rate, and hospital charges in a cohort of spine surgery patients.

METHODS:

We retrospectively reviewed 578 spine surgery patients (lumbar microdiskectomy [LMD], anterior cervical decompression and fusion [ACDF], and lumbar decompression and fusion [LDF]). Differences in length of stay and hospital charges as well as risk factors and correlation with infection and readmission rates were studied.

RESULTS:

Postoperative fever occurred in 41.7% of all spine surgery patients and more often in LDF patients (77.2%). Type of surgery was the most important variable affecting the prevalence of postoperative fever. Significant differences in length of stay were elicited between patients with and without postoperative fever in the ACDF and LMD groups and in hospital cost in the LMD group. The average length of stay was 2.41 vs 4.47 (P &lt; .01) in the LMD group, 1.67 vs 2.80 (P &lt; .05) in the ACDF group, and 5.03 vs 5.65 (P &gt; .05) in the LDF group. The average hospital charges were $16 261 vs $22 166 (P &lt; .01) in the LMD group, $26 021 vs $29 125 (P &gt; .05) in the ACDF group, and $53 627 vs $53 210 (P &gt; .05) in the LDF group. Obesity, female sex, and ≥102°F postoperative temperature were the most significant predictors of infection. Delayed discharge referable to postoperative fever did not seem to influence the infection readmission rate.

CONCLUSION:

Postoperative fever in spine surgery patients is associated with a delay in patient discharge and increases in hospital charges. Postoperative fever discharge guidelines should be regularly and publicly subjected to appropriate cost-benefit analysis.

The Efficacy of Blood Culture in Postoperative Patients

Blood cultures are often obtained in postoperative patients to rule out bloodstream infections. Our study objectives were to determine the efficacy of blood cultures in postoperative patients with suspected sepsis and to determine variables predisposing patients to positive cultures. This was a retrospective study including patients with blood cultures drawn from January to March 2009 at our institution. We recorded demographics, presence of fever (temperature 101.5°F or higher), elevated white blood cell count (12,000/μL or greater), central line, diabetes, intensive care unit admission, postoperative day of blood draw, National Research Council surgical wound classification, and pre- or postoperative antibiotics. Blood cultures were drawn from 150 patients undergoing surgery within 30 days prior. Sixteen had positive cultures and nine were true-positives (6.3%). There was no statistical difference ( P > 0.05) between patients with positive and negative cultures except that those with negative cultures were more likely to have received preoperative antibiotics ( P = 0.0186). Blood cultures are invasive, expensive tests with low yield. We recommend that blood cultures be drawn in patients not receiving preoperative antibiotics who have undergone surgery more than 4 days before culture.

The "fever workup" and respiratory culture practice in critically ill trauma patients

PURPOSE

Fever and leukocytosis (FAL) in critically ill patients often triggers a "workup" that includes a respiratory secretion culture (RCx). We evaluated our respiratory culture practice associated with FAL. We hypothesized that FAL would be associated with a RCx, but would not be associated with a positive culture or treating a respiratory infection in critically injured patients during their first 14 intensive care unit (ICU) days.

MATERIALS AND METHODS

An 18-month retrospective analysis was performed on consecutive ICU trauma patients admitted for 2 days or more to a level I trauma center. Data collected included demographics, injuries, RCxs (bronchoalveolar lavage or tracheal aspirate), maximum daily temperature, and a daily leukocyte count during the first 14 ICU days.

RESULTS

A total of 510 patients with a mean age of 49 and injury severity score of 19 were evaluated for a total of 3839 patient-days. Two hundred eleven patients had 489 RCxs obtained (2.4 RCxs/patient); 94 (19%) were obtained on consecutive days. Obtaining a RCx was associated with fever (relative risk, 4.8; 95% confidence interval, 4.1-5.8) and the combination of FAL (relative risk, 2.6; 95% confidence interval, 2.2-3.1), but not leukocytosis alone. Fever, leukocytosis, or FAL did not predict a positive RCx. One hundred twenty-eight patients were treated for a respiratory infection. Treatment of respiratory infections was contrary to the RCx results 24% of the time. The sensitivity and specificity of a positive RCx being associated with respiratory infection were 97% and 46%, respectively.

CONCLUSIONS

Fever and leukocytosis were associated with the decision to obtain RCxs but were not associated with positive RCxs in our ICU practice. Respiratory secretion culture results had a low specificity and did not consistently impact treatment decisions. Factors other than fever and leukocytosis alone should influence the decision to obtain RCxs during the first 14 days in the ICU after trauma.

Cost and effectiveness of postoperative fever diagnostic evaluation in total joint arthroplasty patients

The purpose of this study is to examine the characteristics and costs of postoperative fever diagnostic evaluations after total joint arthroplasty. All patients who underwent hip and knee arthroplasty (n = 1100) at a single institution for a 2-year period were included. Fever (temperature > or = 38.5 degrees C) occurred in 15% of patients. The rate of positive tests was as follows: chest radiograph (2%), blood culture (6%), urine culture (22%), and urinalysis (23.7%). Fever occurring after postoperative day 3 (odds ratio [OR] 23.3; P < .001) and multiple days febrile (OR, 8.6; P = .003) are independent predictors of a positive workup, and patients with a maximum temperature of 39.0 degrees C or higher (25.4% vs 6.9%; P = .001) had a significantly higher rate of positive fever evaluations. The total direct cost associated with fever evaluations was $73 878, and cost per change in clinical management was $8209. Fever is a common occurrence after hip and knee arthroplasty, and many elements of an infectious evaluation are costly and clinically unnecessary.

Early postoperative fever and the "routine" fever work-up: results of a prospective study

BACKGROUND

Fever in the postoperative period frequently results in a battery of diagnostic tests in search of an etiology. We sought to evaluate the incidence and utility of extensive postoperative fever evaluations in a teaching hospital setting.

MATERIALS AND METHODS

Prospective observational study of all adult patients undergoing in-patient general surgical procedures during a 13-mo period. Patients experiencing an early postoperative fever (>100.4° F in the first 72 h) had data collected on their evaluation, the yield of the diagnostic studies, and whether an infectious diagnosis was made.

RESULTS

Of 1032 surgical procedures, 245 (23.7%) patients experienced an early postoperative fever. One hundred patients (9.7%) underwent documented fever evaluation. Thirty-five (35%) had blood cultures with no positive results among elective surgery patients. Forty-six patients (46%) had urine cultures sent, of which four infections were diagnosed (8.9%). Fifty chest radiographs were performed, but the diagnosis of pneumonia was made by only three (6.0%). Ultimately, 18 febrile patients (18%) were diagnosed with an infectious source, in nine of these patients the physical exam and clinical picture accurately diagnosed the infection without need for further testing.

CONCLUSION

Early postoperative fever is a common event and rarely caused by an infection. A brief bedside evaluation has the highest yield for determining the fever etiology, and extensive evaluations with cultures and chest imaging have little to no benefit in patients admitted for elective surgery.

Postoperative pelvic infections

Infectious morbidity affecting the postoperative course has long been a concern for obstetricians and gynecologists. The incidence of postoperative infections approaches 38%. The third most common nosocomial infection is surgical site infection. The realm of postoperative infections includes obstetric and gynecologic sources. An understanding of the basic fundamentals of the vaginal flora and addressing host and surgical risk factors can aid in prevention of postoperative infections, which result in significant morbidity and mortality.

Does Fever at the Time of Discharge Have Any Impact on the Incidence of Readmission?

Most physicians believe that patients who have fever within 24 hours of the planned date of discharge should be kept in the hospital until the fever resolves. A search of the literature revealed very few articles addressing this topic. The object of this study was to review a number of patient discharges from the surgical service and to document the presence or absence of fever within 24 hours of the time of discharge. The primary end point of the study was to determine the rate of readmission for both patients discharged with fever and those discharged without fever. Secondary end points were to determine whether the readmission was related to the original discharge diagnosis or the presence of fever at the time of discharge. The records of all adult patients with a hospital length of stay of ≥5 days discharged from the surgical and gynecology services from April through July of 2007 were reviewed. Deaths were excluded. The following data elements were recorded: primary discharge diagnosis; age; highest recorded temperature within 24 hours of discharge; date time and cause of readmission within 30 days; and outcome. Fever was defined as a temperature of ≥100° F. Data were entered into an Excel (Microsoft, Redmond, WA) spreadsheet, and statistical analysis was performed using χ2 and Fisher's exact tests using Primer of Biostatistics© (McGraw-Hill, New York, NY). The records of 300 consecutive patients were reviewed. Follow-up was available for 86.7 per cent of the patients, 84.4 per cent of the febrile patients, and 87.1 per cent of the nonfebrile patients. A fever of ≥100° within 24 hours of discharge was noted in 45 (15.0%) patients. The mean fever was 100.5°, with a range of 100° to 102.1°. There were 38 readmissions. Of the 45 patients with fever, seven (15.6%) were readmitted. Of those seven, four readmissions were related to the previous admitting diagnosis. Of the patients who were discharged without fever, 31 (12.2%) were readmitted with 24 of those read-missions for diagnoses related to the first admission. The rate of readmission for fever and nonfever patients was not statistically significantly different (P = 0.697). Similarly, the rate of related versus nonrelated diagnoses in both the fever and nonfever groups was not statistically significantly different (P = 0.351). The presence or absence of fever within 24 hours of patient discharge seems to have no impact on the rate of readmission within 30 days.

Postoperative fever and survival in patients after open resection for colorectal cancer: a long-term follow-up study of 2,311 prospectively enrolled patients

PURPOSE

Two reports on the impact of postoperative fever on survival after surgery in patients with colorectal cancer yielded contradictory results. Our study examined possible associations between postoperative fever and long-term survival of patients who underwent resection of colorectal cancer.

METHODS

We investigated 2,311 consecutive patients who underwent elective open colorectal resection for primary colorectal cancer at a single institution between 1995 and 1998. The primary end points were cancer-specific and overall survival. Multiple covariate impact of risk factors on survival rates was assessed by Cox regression analysis.

RESULTS

A total of 252 patients (12.2 percent) developed postoperative fever. The most important independent risk factor for postoperative fever was postoperative morbidity (odds ratio, 4.9; 95 percent confidence interval, 3.7-6.6) followed by blood transfusion (1.7; 1.2-2.2), Stage IV disease (1.6; 1.1-2.2), male gender (1.4; 1.0-1.9), and rectal cancer (1.4; 1.0-1.8). Cox regression modeling indicated that stage, histology, tumor location, and blood transfusion were statistically significant covariate predictors for cancer-specific survival. Postoperative fever was not independently associated with cancer-specific or overall survival.

CONCLUSIONS

This study did not support the hypothesis that postoperative fever is an independent prognostic factor after colorectal resection for primary colorectal cancer.

Fever evaluations after colorectal surgery: identification of risk factors that increase yield and decrease cost

PURPOSE

This study was designed to evaluate the yield and cost of fever evaluations in average-risk inpatients after elective colorectal surgery.

METHODS

A 12-month, retrospective study was performed on patients who developed a postoperative fever > or = 38 degrees C after elective colorectal surgery. A positive fever evaluation was defined as a blood culture, urine culture, chest x-ray, or abdominal CT result that led to a change in patient management. Logistic regression, Fisher's exact test, and chi-squared test were used; odds ratios were calculated.

RESULTS

Of 133 patients, 26 percent had a positive evaluation. Blood culture, urine culture, chest x-ray, and CT were positive in 3, 8, 7, and 46 percent, respectively. Risk factors for a positive fever evaluation were temperature > or = 38.5 degrees C, fever evaluation after postoperative Day 6, and a clinical manifestation of systemic inflammatory response syndrome other than fever (all, P < 0.01). The cost per positive fever evaluation for the entire group, patients with 2 risk factors, or patients with 3 risk factors was $5,600, $4,200, and $2,140, respectively.

CONCLUSIONS

The current approach to fever evaluation after elective colorectal surgery is low yield and costly. High fever, late postoperative fever, and systemic inflammatory response syndrome are risk factors for a positive fever evaluation after colorectal surgery.

Fever and leukocytosis in critically ill trauma patients: it's not the urine

BACKGROUND

Infectious complications are a major cause of morbidity and mortality in critically ill trauma patients. Therefore, fever and leukocytosis often trigger an extensive laboratory workup that includes a urine culture (UCx). The purposes of this study were to: 1) Define the current practice for obtaining UCxs in trauma patients admitted to the surgical and trauma intensive care unit (STICU); and 2) determine if there is an association between fever or leukocytosis and urinary tract infections (UTIs) during the initial 14 hospital days.

METHODS

An 18-month retrospective cohort analysis was performed on consecutive trauma patients admitted for at least two days to the STICU at a level I trauma center. Data collected included demographics, injuries, and daily maximal temperature (T(max)), leukocyte count, and UCx results for the first 14 days. Fever and leukocytosis were defined as T(max) > or =38.5 degrees C and leukocyte count > or =12,000/mm(3), respectively. Urinary tract infections were diagnosed with a positive UCx (> or =10(5) organisms/mL of urine).

RESULTS

Five hundred ten patients were evaluated for a total of 3,839 patient-days. Their mean age and Injury Severity Score were 49 +/- 1 years and 19 +/- 1 points, respectively. Seventy-two percent were men, and 91% had sustained blunt injuries. Four hundred seven UCxs were obtained; 42 patients (8%) had 60 UTIs. The cohort had an indwelling urinary catheter for 97% of the patient-days, yielding an infection density of 16 UTIs/1,000 urinary catheter-days. There was a significant association between obtaining a UCx and fever and between fever and leukocytosis (both, p < 0.001), but no association of UTI with fever, leukocytosis, or the combination of fever and leukocytosis. Analysis using temperature and leukocyte count as continuous variables identified no temperature or leukocyte range associated with UTIs. Independent risk factors for UTI calculated by logistic regression were female sex, older age, low Injury Severity Score, and no antibiotics within 24 h before the UCx was obtained.

CONCLUSIONS

The practice of obtaining a UCx from the STICU trauma patient was related to fever and fever with leukocytosis. However, neither fever nor leukocytosis nor both were associated with UTIs. These data suggest that there is an unnecessary emphasis on UTI as a source of fever and leukocytosis in injured patients during their first 14 STICU days. Our results suggest that the paradigm for evaluating UTI as a cause of fever needs to be reevaluated in critically ill trauma patients.