Computed tomography localization of the appendix in the pediatric population relative to the lumbar spine.

BACKGROUND: Computed tomography (CT) is commonly used to evaluate suspected acute appendicitis. Although very effective, CT uses ionizing radiation, exposing patients to an increased risk of cancer. OBJECTIVE: This study assessed the potential for decreasing the field of view of the CT (and therefore the dose to the patient) in the evaluation of suspected acute appendicitis in children. MATERIALS AND METHODS: This study was a retrospective review of prospectively collected data from 212 consecutive patients who underwent CT for suspected acute appendicitis. The most superior aspect of the appendix with respect to vertebral bodies was recorded. Age, gender and diagnosis (negative, acute appendicitis or alternative diagnosis) were noted. RESULTS: The appendix was visualized in 190 of 212 subjects (89.6%). Overall, all visualized appendixes were located at or below the level of L1. Sixty-three of the subjects (29.7%) were diagnosed with acute appendicitis via CT imaging. All appendixes in patients with acute appendicitis were located at or below the level of the L3 vertebral body, predominating at the level of L5. Six subjects (3.1%) received alternative diagnoses, including pneumonia, pyelonephritis, small bowel obstruction and infected urachal cyst. There were no differences in appendix location with regard to diagnosis, gender, or age (P=0.664, 0.748 and 0.705, respectively). CONCLUSION: CT field of view may be decreased to the level of L1 or L3 superiorly, decreasing radiation dose without affecting the rate of appendix visualization.

Traumatic Abruptio Placenta Scale (TAPS): a proposed grading system of computed tomography evaluation of placental abruption in the trauma patient.

Placental abruption (PA) is one of the worst possible manifestations of injury in the pregnant trauma patient with ultrasound as the current initial imaging examination of choice, despite its known limitations in placental evaluation. Pregnant patients who undergo computed tomography (CT) for evaluation of potential maternal injuries provide an additional source of imaging for placental evaluation; however, few studies have delineated normal and abnormal placental appearance, therefore resulting in insufficient placental assessments on pregnant trauma patients. Retrospective literature analysis was performed to provide a structured descriptive classification of normal and abnormal placental appearance on CT. By offering a structured system of placental appearance, radiologists will become more familiar with normal variations of the placenta as well as be able to recognize areas of abnormality, furthermore assisting in clinical management efficiency.

Airway risk associated with patients in halo fixation.

Background: The halo fixation device introduces a significant obstacle for clinicians attempting to secure a definitive airway in trauma patients with cervical spine injuries. The authors sought to determine the airway-related mortality rate of adult trauma patients in halo fixation requiring endotracheal intubation. Methods: This study was a retrospective chart review of patients identified between 2007 and 2012. Only adult trauma patients who were intubated while in halo fixation were included in the study. Results: A total of 46 patients underwent 60 intubations while in halo. On five occasions, (8.3%) patients were unable to be intubated and required an emergent surgical airway. Two (4.4%) of the patients out of our study population died specifically due to airway complications. Elective intubations had a failure rate of 5.8% but had no related permanent morbidity or mortality. In contrast to that, 25% of non-elective intubations failed and resulted in the deaths of two patients. The association between mortality and non-elective intubations was statistically highly significant (P = 0.0003). Conclusion: The failed intubation and airway-related mortality rates of patients in halo fixation were substantial in this study. This finding suggests that the halo device itself may present a major obstacle in airway management. Therefore, heightened vigilance is appropriate for intubations of patients in halo fixation.

Thoracic irrigation for prevention of secondary intervention after thoracostomy tube drainage for hemothorax: A Western Trauma Association multi-center study.

BACKGROUND: Retained hemothorax (rHTX) requiring intervention occurs in up to 20% of patients who undergo chest tube (TT) placement for a hemothorax (HTX). Thoracic irrigation at the time of TT placement decreases the need for secondary intervention in this patient group but those findings are limited because of the single center design. A multi-center study was conducted to evaluate the effectiveness of thoracic irrigation. METHODS: A multi-center, prospective, observational study was conducted between June 2018 and July 2023. Eleven sites contributed patients. Patients were included if they had a TT placed for a HTX and were excluded if: age < 18 years, TT for pneumothorax, thoracotomy or VATS performed within 6 hours of TT, TT >24 hours after injury, TT removed <24 hours, or death within 48 hours. Thoracic irrigation was performed at the discretion of the attending. Each hemithorax was considered separately if bilateral HTX. The primary outcome was secondary intervention for HTX-related complications (rHTX, effusion, or empyema). Secondary intervention was defined as: TT placement, instillation of thrombolytics, VATS, or thoracotomy. Irrigated and non-irrigated hemithoraces were compared using a propensity weighted analysis with age, sex, mechanism of injury, Abbreviated Injury Scale (AIS) chest and TT size as predictors. RESULTS: 493 patients with 462 treated hemothoraces were included, 123 (25%) had thoracic irrigation at TT placement. There were no significant demographic differences between the cohorts. Fifty-seven secondary interventions were performed, 10 (8%) and 47 (13%) in the irrigated and non-irrigated groups, respectively (p = 0.015). Propensity weighted analysis demonstrated a reduction in secondary interventions in the irrigated cohort (Odds Ratio 0.56 (0.34-0.85); p = 0.005). CONCLUSION: This Western Trauma Association multi-center study demonstrates a benefit of thoracic irrigation at the time of TT placement for a HTX. Thoracic irrigation reduces the odds of a secondary intervention for rHTX-related complications by 44%. LEVEL OF EVIDENCE: Therapeutic Study, Level II.

Risk factors for blunt cerebrovascular injury in children: do they mimic those seen in adults?

BACKGROUND: Eastern Association for the Surgery of Trauma guideline for the evaluation of blunt cerebrovascular injury (BCVI) states that pediatric trauma patients should be evaluated using the same criteria as the adult population. The purpose of our study was to determine whether adult criteria translate to the pediatric population. METHODS: Retrospective evaluation was performed at a Level I trauma center of blunt pediatric trauma patients (age <15 years) presenting over a 5-year period. Data obtained included patient demographics, presence of adult risk factors for BCVI (Glasgow coma scale ≤8, skull base fracture, cervical spine fracture, complex facial fractures, and soft tissue injury to the neck), presence of signs/symptoms of BCVI, method of evaluation, treatment, and outcome. RESULTS: A total of 1,209 pediatric trauma patients were admitted during the study period. While 128 patients met criteria on retrospective review for evaluation based on Eastern Association for the Surgery of Trauma criteria, only 52 patients (42%) received subsequent radiographic evaluation. In all, 14 carotid artery or vertebral artery injuries were identified in 11 patients (all admissions, 0.9% incidence; all screened, 21% incidence). Adult risk factors were present in 91% of patients diagnosed with an injury. Major thoracic injury was found in 67% of patients with carotid artery injuries. Cervical spine fracture was found in 100% of patients with vertebral artery injuries. Stroke occurred in four patients (36%). Stroke rate after admission for untreated patients was 38% (3/8) versus 0.0% in those treated (0/2). Mortality was 27% because of concomitant severe traumatic brain injury. CONCLUSION: Risk factors for BCVI in the pediatric trauma patient appear to mimic those of the adult patient.

Significant pediatric morbidity and mortality from intracranial ballistic injuries caused by nonpowder gunshot wounds. A case series.

Nonpowder (ball-bearing and pellet) weapons derive their source of energy from compressed air or carbon dioxide. Such weapons are dangerous toys that cause serious injuries and even death to children and adolescents. A retrospective chart review study was undertaken to describe nonpowder gun injuries at a southwestern US urban level I adult and pediatric trauma center. Specific emphasis was placed on intracranial injuries. Over the past 6 years, a total of 29 pediatric and 7 adult patients were identified as having nonpowder firearm injuries. The patient population was overwhelmingly male (89.7%; mean age, 11 years). Overall, 17 out of 29 pediatric patients (56.8%) sustained serious injury. Nine patients (30.0%) required operation, 6 (20.7%) sustained significant morbidity, and there were 2 deaths (6.9%). Injuries to the brain, eye, head, and neck were the most common sites of injury (65.6%). Specific intracranial injuries in 3 pediatric patients are described that resulted in the death of 2 children. We suggest that age warning should be adjusted to 18 years or older for unsupervised use to be considered safe of these potentially lethal weapons.

The relationship of plasma glucose and glycosylated hemoglobin A1C levels among nondiabetic trauma patients.

OBJECTIVE: : Hyperglycemia (blood glucose >/=110 mg/dL) in trauma patients without a known history of diabetes mellitus (DM) is often attributed to the metabolic stress response of injury. We studied whether this hyperglycemia may actually indicate the presence of occult DM (ODM) as demonstrated by elevated glycosylated hemoglobin A1C (gHbA1C). METHODS: : After obtaining approval from the Institutional Review Board, a prospective, sequential case series study of nondiabetic adult patients presenting to an urban Level I trauma center from September 2006 to February 2007 was performed. In addition to basic demographics, all hyperglycemic patients had a measured gHbA1C. ODM was diagnosed when gHbA1C was >/=6%. RESULTS: : A total of 1,039 trauma patients were screened with 192 (18%) noted to be hyperglycemic. Of these 192 patients, 22% (n = 42) were found to have an elevated gHbA1C. Using logistic regression, being older (Odds ratio [OR] = 1.04; p < 0.004), having a higher body mass index (BMI) (OR = 1.12; p < 0.003), and being Native American (OR = 5.08; p < 0.017) were each identified as significant risk factors for elevated gHbA1C levels and the diagnosis of ODM. In contrast, the magnitude of observed hyperglycemia, gender, or other races were not shown to be significant risk factors for the presence of ODM. CONCLUSION: : Almost a quarter of nondiabetic trauma patients presenting with hyperglycemia were found to have elevated gHbA1C levels and ODM. Risk factors for ODM included advancing age and body mass index as well as being Native American. The hyperglycemia seen in trauma patients should not solely be attributed to the hormonal and metabolic response to injury; wider ODM screening for both acute management strategies and long-term health benefits is warranted.

Computed tomographic imaging in the pediatric patient with a seatbelt sign: still not good enough.

PURPOSE: Considering the improvements in CT over the past decade, this study aimed to determine whether CT can diagnose HVI in pediatric trauma patients with seatbelt signs (SBS). METHODS: We retrospectively identified pediatric patients with SBS who had abdominopelvic CT performed on initial evaluation over 5 1/2years. Abnormal CT was defined by identification of any intra-abdominal abnormality possibly related to trauma. RESULTS: One hundred twenty patients met inclusion criteria. CT was abnormal in 38/120 (32%) patients: 34 scans had evidence of HVI and 6 showed solid organ injury (SOI). Of the 34 with suspicion for HVI, 15 (44%) had small amounts of isolated pelvic free fluid as the only abnormal CT finding; none required intervention. Ultimately, 16/120 (13%) patients suffered HVI and underwent celiotomy. Three patients initially had a normal CT but required celiotomy for clinical deterioration within 20h of presentation. False negative CT rate was 3.6%. The sensitivity, specificity and accuracy of CT to diagnose significant HVI in the presence of SBS were 81%, 80%, and 80%, respectively. CONCLUSIONS: Despite improvements in CT, pediatric patients with SBS may have HVI not evident on initial CT confirming the need to observation for delayed manifestation of HVI. LEVEL OF EVIDENCE: Level II Study of a Diagnostic Test.

Resuscitative endovascular balloon occlusion of the aorta with a low profile, wire free device: A game changer?

A 24 year old male arrived to our hospital after a motor cycle crash with evidence of a traumatic brain injury and in hemorrhagic shock not responsive to volume administration. Resuscitative Endovascular Balloon Occlusion of the Aorta (REBOA) was performed in a timely fashion using a new, low profile, wire free device. This lead to rapid reversal of hypotension while his bleeding source was sought and controlled. Recently, REBOA has emerged as an adjunct in the hypotensive trauma patient with noncompressible torso hemorrhage. As first described, this procedure makes use of commonly available vascular surgery and endovascular products requiring large introducer sheaths (12-14 French) and long guidewires. Concerns regarding this technique center around the safety and feasibility of using such equipment in the emergency setting outside an angiography suite. This has likely limited widespread adoption of this technique. To address these concerns, newer products designed to be placed through a smaller sheath (7 French) and without the use of guidewires have been developed. Here we report on our first clinical use of such a device that we believe represents a significant advance in the care of the trauma patient.

Closed therapy of thoracic and lumbar vertebral body fractures in trauma patients.

BACKGROUND: The failure rate for the closed/non-surgical treatment of thoracic and lumbar vertebral body fractures (TLVBF) in trauma patients has not been adequately evaluated utilizing computed tomography (CT) studies. METHODS: From 2007 to 2008, consecutive trauma patients, who met inclusion criteria, with a CT diagnosis of acute TLVBF undergoing closed treatment were assessed. The failure rates for closed therapy, at 3 months post-trauma, were defined by progressive deformity, vertebral body collapse, or symptomatic/asymptomatic pseudarthrosis. The Arbeitsgemeinschaft für Osteosynthesefragen (AO) classification was utilized to classify the fractures (groups A1 and non-A1 fractures) and were successively followed with CT studies. RESULTS: There were 54 patients with 91 fractures included in the study; 66 were A1 fractures, and 25 were non-A1 fractures. All had rigid bracing applied with flat and upright X-ray films performed to rule out instability. None had sustained spinal cord injuries. Thirteen patients (24%) failed closed therapy [e.g. 13 failed fractures (14%) out of 91 total fractures]. Five failed radiographically only (asymptomatic), and eight failed radiographically and clinically (symptomatic). A1 fractures had a 4.5% failure rate, while non-A1 fractures failed at a rate of 40%. CONCLUSION: Failure of closed therapy for TLVBF in the trauma population is not insignificant. Non-A1 fractures had a much higher failure rate when compared to A1 fractures. We recommend close follow-up particularly of non-A1 fractures treated in closed fashion using successive CT studies.

Goal directed enoxaparin dosing provides superior chemoprophylaxis against deep vein thrombosis.

INTRODUCTION: Optimal enoxaparin dosing for deep venous thrombosis (DVT) prophylaxis remains elusive. Prior research demonstrated that trauma patients at increased risk for DVT based upon Greenfield's risk assessment profile (RAP) have DVT rates of 10.8% despite prophylaxis. The aim of this study was to determine if goal directed prophylactic enoxaparin dosing to achieve anti-Xa levels of 0.3-0.5IU/ml would decrease DVT rates without increased complications. MATERIALS AND METHODS: Retrospective review of trauma patients having received prophylactic enoxaparin and appropriately timed anti-Xa levels was performed. Dosage was adjusted to maintain an anti-Xa level of 0.3-0.5IU/ml. RAP was determined on each patient. A score of ≥5 was considered high risk for DVT. Sub-analysis was performed on patients who received duplex examinations subsequent to initiation of enoxaparin therapy to determine the incidence of DVT. RESULTS: 306 patients met inclusion criteria. Goal anti-Xa levels were met initially in only 46% of patients despite dosing of >40mg twice daily in 81% of patients; however, with titration, goal anti-Xa levels were achieved in an additional 109 patients (36%). An average enoxaparin dosage of 0.55mg/kg twice daily was required for adequacy. Bleeding complications were identified in five patients (1.6%) with three requiring intervention. There were no documented episodes of HIT. Subsequent duplex data was available in 197 patients with 90% having a RAP score >5. Overall, five DVTs (2.5%) were identified and all occurred in the high-risk group. All patients were asymptomatic at the time of diagnosis. CONCLUSION: An increased anti-Xa range of 0.3-0.5IU/ml was attainable but frequently required titration of enoxaparin dosage. This produced a lower rate of DVT than previously published without increased complications.

Computed tomographic imaging interpretation improves fetal outcomes after maternal trauma.

BACKGROUND: Computed tomography (CT) has been validated to identify and classify placental abruption following blunt trauma. The purpose of this study was to demonstrate improvement in fetal survival when delivery occurs by protocol at the first sign of class III fetal heart rate tracing in pregnant trauma patients with a viable fetus on arrival and CT evidence of placental perfusion 50% or less secondary to placental abruption. METHODS: This is a retrospective review of pregnant trauma patients at 26 weeks' gestation or greater who underwent abdominopelvic CT as part of their initial evaluation. Charts were reviewed for CT interpretation of placental pathology with classification of placental abruption based upon enhancement (Grade 1, >50% perfusion; Grade 2, 25%-50% perfusion; Grade 3, <25% perfusion), as well as need for delivery and fetal outcomes. RESULTS: Forty-one patients met inclusion criteria. Computed tomography revealed evidence of placental abruption in six patients (15%): Grade 1, one patient, Grade 2, one patient, and Grade 3, four patients. Gestational ages ranged from 26 to 39 weeks. All patients with placental abruption of Grade 2 or greater developed concerning fetal heart tracings and underwent delivery emergently at first sign. Abruption was confirmed intraoperatively in all cases. Each birth was viable, and Apgar scores at 10 minutes were greater than 7 in 80% of infants, all of whom were ultimately discharged home. The remaining infant was transferred to an outside facility. CONCLUSIONS: Delivery at first sign of nonreassuring fetal heart rate tracings in pregnant trauma patients (third trimester) with placental abruption of Grade 2 or greater can lead to improved fetal outcome. LEVEL OF EVIDENCE: Therapeutic/care management study, level III.

Does Self-Assessment Improve the Effectiveness of Grand Rounds Lectures in a Community-Based Teaching Hospital?

OBJECTIVE: To determine whether use of self-assessment (SA) questions affects the effectiveness of weekly didactic grand rounds presentations. DESIGN: From 26 consecutive grand rounds presentations from August 2013 to April 2014, a 52-question multiple-choice test was administered based on 2 questions from each presentation. SETTING: Community teaching institution. PARTICIPANTS: General surgery residents, students, and attending physicians. RESULTS: The test was administered to 66 participants. The mean score was 41.8%. There was no difference in test score based on experience with similar scores for junior residents, senior residents, and attending surgeons (43%, 46%, and 44%; p = 0.13). Most participants felt they would be most interested in presentations directly related to their surgical specialty. Participants, however, did not score differently on topics which were the focus of the program (40% vs. 42%; p = 0.85). Journal club presentations (39% vs. others 42%; p = 0.33) also did not affect the score. The Pearson correlation coefficient for attendance was 0.49 (p < 0.0001) demonstrated that attendance was very important. Participation in the weekly SA was significantly associated with improved score as those who participated in SA scored over 20% higher than those who did not (59% vs. 38%; p < 0.0001). Based on multiple linear regression for mean score, SA explained the variation in score more than attendance. CONCLUSIONS: The current study found that without preparation approximately 40% of material presented is retained after 10 months. Participation in weekly SA significantly improved retention of information from grand rounds presentations.

Current management of common bile duct stones in a teaching community hospital.

The advent of laparoscopic cholecystectomy (LC) has complicated management of common bile duct (CBD) stones. While LC is routine, laparoscopic CBD exploration (LCBDE) is not, and an algorithm to manage suspected choledocholithiasis has not been uniformly accepted. We evaluated current management of choledocholithiasis. Patients suspected of having CBD stones over a 2-year period were evaluated, and 42 studies in the literature were reviewed. Thirty-two patients were identified. Fourteen patients (44%) had LC with intraoperative cholangiogram (IOC) with no preoperative studies. IOC revealed CBD stones in nine (64%). Seven had CBD exploration (CBDE) at cholecystectomy, and two had postoperative endoscopic retrograde cholangiopancreatography (ERCP). CBDE was successful in five cases, and ERCP was successful in one. Eighteen patients (56%) underwent preoperative ERCP. Five (28%) had no CBD stones. ERCP removed stones in nine patients, and four had open CBDE after failed ERCP. Current literature supports LC with IOC without any preoperative studies. Laparoscopic CBDE is highly successful but depends on surgeon experience. Removing CBD stones with ERCP is also very successful but is associated with increased cost, hospital stay, and complications. We conclude that LC with IOC should be performed without preoperative ERCP when choledocholithiasis is suspected. If found, stones should be removed laparoscopically if possible.

The ability of computed tomography to diagnose placental abruption in the trauma patient.

BACKGROUND: Fetal demise following trauma remains a devastating complication largely owing to placental injury and abruption. Our objective was to determine if abdominopelvic computed tomographic (CT) imaging can assess for placental abruption (PA) when obtained to exclude associated maternal injuries. METHODS: Retrospective review of pregnant trauma patients of 20-week gestation or longer presenting to a trauma center during a 7-year period who underwent CT imaging as part of their initial evaluation. Radiographic images were reviewed by a radiologist for evidence of PA and classified based on percentage of visualized placental enhancement. Blinded to CT results, charts were reviewed by an obstetrician for clinical evidence of PA and classified as strongly positive, possibly positive, or no evidence. RESULTS: A total of 176 patients met inclusion criteria. CT imaging revealed evidence of PA in 61 patients (35%). As the percentage of placental enhancement decreased, patients were more likely to have strong clinical manifestations of PA, reaching statistical significance when enhancement was less than 50%. CT imaging evidence of PA was apparent in all patients who required delivery for nonassuring fetal heart tones. CONCLUSION: CT imaging evaluation of the placenta can accurately identify PA and therefore can help stratify patients at risk for fetal complications. The likelihood of requiring delivery increased as placental enhancement declined to less than 25%. LEVEL OF EVIDENCE: Diagnostic study, level III.

Alternative dosing of prophylactic enoxaparin in the trauma patient: is more the answer?

BACKGROUND: Inadequate anti-factor Xa levels and increased venous thromboembolic events occur in trauma patients receiving standard prophylactic enoxaparin dosing. The aim of this study was to test the hypothesis that higher dosing (40 mg twice daily) would improve peak anti-Xa levels and decrease venous thromboembolism. METHODS: A retrospective review was performed of trauma patients who received prophylactic enoxaparin and peak anti-Xa levels over 27 months. Patients were divided on the basis of dose: group A received 30 mg twice daily, and group B received 40 mg twice daily. Demographics and rates of venous thromboembolism were compared between dose groups and patients with inadequate or adequate anti-Xa levels. RESULTS: One hundred twenty-four patients were included, 90 in group A and 34 in group B. Demographics were similar, except that patients in group B had a higher mean body weight. Despite this, only 9% of group B patients had inadequate anti-Xa levels, compared with 33% of those in group A (P = .01). Imaging studies were available in 69 patients and revealed 8 venous thromboembolic events (P = NS, group A vs group B) with significantly more venous thromboembolic events occurring in patients with low anti-Xa levels (P = .02). CONCLUSIONS: Although higher dosing of enoxaparin led to improved anti-Xa levels, this did not equate to a statistical decrease in venous thromboembolism.

Use of computed tomography in the initial evaluation of anterior abdominal stab wounds.

BACKGROUND: The purpose of this study was to assess the ability of computed tomography (CT) to facilitate initial management decisions in patients with anterior abdominal stab wounds. METHODS: A retrospective review was conducted of patients with anterior abdominal stab wounds who underwent CT over 4.5 years. Any abnormality suspicious for intra-abdominal injury was considered a positive finding on CT. RESULTS: Ninety-eight patients met the study's inclusion criteria. Positive findings on CT were noted in 30 patients (31%), leading to operative intervention in 67%. Injuries were confirmed in 95% of cases, but only 70% were therapeutic. Ten patients had nonoperative management despite positive findings on CT, including 5 patients with solid organ injuries. One patient underwent operative intervention for clinical deterioration, with negative findings. No computed tomographic evidence of injury was noted in the remaining 68 patients (69%), but 1 patient was noted to have a splenic injury while undergoing operative evaluation of the diaphragm. All remaining patients were treated nonoperatively with success. CONCLUSIONS: In patients with anterior abdominal stab wounds, CT should be considered to facilitate initial management decisions, as it has the ability to delineate abnormalities suspicious for injury.

Incidence of blunt cerebrovascular injury in low-risk cervical spine fractures.

BACKGROUND: It has been suggested that specific cervical spine fractures (CSfx) (location at upper cervical spine [CS], subluxation, or involvement of the transverse foramen) are predictive of blunt cerebrovascular injury (BCVI). We sought to determine the incidence of BCVI with CSfx in the absence of high-risk injury patterns. METHODS: We performed a retrospective study in patients with CSfx who underwent evaluation for BCVI. The presence of recognized CS risk factors for BCVI and other risk factors (Glasgow coma score ≤ 8, skull-based fracture, complex facial fractures, soft-tissue neck injury) were reviewed. Patients were divided into 2 groups based on the presence/absence of risk factors. RESULTS: A total of 260 patients had CSfx. When screened for high-risk pattern of injury for BCVI, 168 patients were identified and 13 had a BCVI (8%). The remaining 92 patients had isolated low CSfx (C4-C7) without other risk factors for BCVI. In this group, 2 patients were diagnosed with BCVI (2%). Failure to screen all patients with CSfx would have missed 2 of 15 BCVIs (13%). CONCLUSIONS: We propose that all CS fracture patterns warrant screening for BCVI.

Empiric, broad-spectrum antibiotic therapy with an aggressive de-escalation strategy does not induce gram-negative pathogen resistance in ventilator-associated pneumonia.

BACKGROUND: Early, empiric, broad-spectrum antibiotics followed by de-escalation to pathogen-specific therapy is the standard of care for ventilator-associated pneumonia (VAP). In our surgical intensive care unit (SICU), imipenem-cilastatin (I-C) in combination with tobramycin (TOB) or levofloxacin (LEV) has been used until quantitative bronchoalveolar lavage results are finalized, at which time de-escalation occurs to pathogen-specific agents. With this practice, however, alterations in antimicrobial resistance remain a concern. Our hypothesis was that this strict regimen does not alter antimicrobial susceptibility of common gram-negative VAP pathogens in our SICU. METHODS: After Institutional Review Board approval, a retrospective review of SICU-specific antibiograms was performed for the sensitivities of common gram-negative VAP pathogens. Time periods were defined as early (January-June 2005) and late (July-December 2006). Chart review of empiric and de-escalation antibiotic usage was obtained. Data were collated, and statistical significance was assessed with the chi-square test using the on-line Simple Interactive Statistical Analysis tool. RESULTS: Imipenem-cilastatin was used 198 times for empiric VAP coverage (811 patient-days), whereas TOB and LEV were given a total of 149 (564 patient-days) and 61 (320 patient-days) times, respectively. Collectively, the susceptibility of gram-negative organisms to I-C did not change (early 91.4%; late 97%; p = 0.33). Individually, non-significant trends to greater sensitivity to I-C were noted for both Pseudomonas aeruginosa (early 85.7%; late 90.9%; p = 0.73) and Acinetobacter baumannii (early 80%; late 100%; p = 0.13). Further, both TOB (early 77.1%; late 70.0%; p = 0.49) and LEV (early 74.3%; late 70.0%; p = 0.67) were found to maintain their susceptibility profiles. The frequency of resistant gram-positive VAPs was unchanged during the study period. Our de-escalation compliance (by 96 h) was 78% for I-C, 77.2% for TOB, and 59% for LEV. When infections requiring I-C were removed from the analysis, de-escalation compliance was improved to 92%. CONCLUSIONS: In our SICU, early, empiric broad-spectrum VAP therapy followed by de-escalation to pathogen-specific agents did not alter antimicrobial resistance and is a valid practice. Further, our compliance with de-escalation practices was higher than published rates.