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Timothy C Fabian

Publications and source records attributed to Timothy C Fabian.

At least 37 records · Page 2Linked to original sources
PubMed2004

Cerebral perfusion pressure elevation with oxygen-carrying pressor after traumatic brain injury and hypotension in Swine.

BACKGROUND: Previously, we had shown that elevation of cerebral perfusion pressure, using pressors, improved short-term outcomes after traumatic brain injury and hemorrhagic shock in swine. The current study evaluates outcomes after resuscitation with diaspirin cross-linked hemoglobin (DCLHb)--a hemoglobin-based oxygen carrier with pressor activity--in the same swine model of traumatic brain injury and hemorrhagic shock. METHODS: Anesthetized and ventilated swine received traumatic brain injury via cortical fluid percussion (6-8 atm) followed by 45% blood volume hemorrhage. One hour later, animals were randomized to either a control group (SAL) resuscitated with normal saline equal to three times shed blood volume or to one of two experimental groups resuscitated with DCLHb. The two experimental groups consisted of a low-dose group, resuscitated with 250 mL of DCLHb (Hb1), and a high-dose group, resuscitated with 500 mL of DCLHb (Hb2). Animals were observed for 210 minutes postresuscitation. Outcomes evaluated were cerebral oxygenation by measuring partial pressure and saturation of oxygen in cerebrovenous blood; cerebral function by evaluating the preservation and magnitude of cerebrovascular carbon dioxide reactivity; and brain structural damage by semiquantitatively assessing beta amyloid precursor protein positive axons. RESULTS: Postresuscitation, cerebral perfusion pressure was higher in the DCLHb groups (p < 0.05, Hb1 and Hb2 vs. SAL), and intracranial pressure was lower in the Hb2 group (p < 0.05 vs. SAL). Cerebrovenous oxygen level was similar in all groups (p > 0.05). At baseline, 5% carbon dioxide evoked a 16 +/- 1% increase in cerebrovenous oxygen saturation, indicating vasodilatation. At 210 minutes, this response was nearly absent in SAL (4 +/- 4%) (p < 0.05 vs. baseline) and Hb1 (1 +/- 5%), but was partially preserved in Hb2 (9 +/- 5%). There was no intergroup difference in beta amyloid precursor protein positive axons. Five of 20 SAL and 0 of 13 DCLHb animals developed brain death (flat electroencephalogram) (p = 0.05, SAL vs. DCLHb). Postresuscitation, DCLHb animals maintained higher mean pulmonary arterial pressure (28 +/- 1 mm Hg, SAL; 42 +/- 1 mm Hg, Hb1; 45 +/- 1 mm Hg, Hb2) (p < 0.05, Hb1 and Hb2 vs. SAL) and lower cardiac output (3.9 +/- 1.6 L/min, SAL; 2.6 +/- 0.1 L/min, Hb1; 2.7 +/- 0.1 L/min, Hb2) (p < 0.05, Hb1 and Hb2 vs. SAL). Three Hb2 animals died as a result of cardiac failure, and one SAL animal died as a result of irreversible shock. CONCLUSION: In this swine model of traumatic brain injury and hemorrhagic shock, resuscitation with DCLHb maintained a higher cerebral perfusion pressure. Low-dose DCLHb (minimal increase in oxygen carriage) failed to significantly improve short-term outcome. With high-dose DCLHb (significant improvement in oxygen carriage), intracranial pressure was lower and cerebrovascular carbon dioxide reactivity was partially preserved; however, this was at the cost of poorer cardiac performance secondary to high afterload.

Amyloid beta-Protein Precursor↗
PubMed2004

The appropriate diagnostic threshold for ventilator-associated pneumonia using quantitative cultures.

BACKGROUND: The use of quantitative cultures of the bronchoalveolar lavage (BAL) effluent to distinguish between posttraumatic inflammatory response and ventilator-associated pneumonia (VAP) is becoming more common. However, the diagnostic threshold of either 10 or 10 colonies/mL remains debatable. Because mortality from VAP is related to treatment delay, some have chosen a lower diagnostic threshold (>10 colonies/mL). This may result in unnecessary antibiotic use with its sequelae: increased resistant organisms, antibiotic-related complications, and increased costs. The purpose of this study is to determine the optimal diagnostic threshold for VAP diagnosis using quantitative cultures of the BAL effluent. METHODS: Data on patients with fiberoptic bronchoscopy with BAL are maintained in a prospectively collected database at our Level I trauma center. This database was reviewed for timing and frequency of BAL and the colony counts of each organism identified. Indication for bronchoscopy was clinical evidence of VAP. VAP was defined as >10 colonies/mL in the BAL effluent. A false-negative BAL was defined as any patient who had <10 colonies/mL and developed VAP with the same organism up to 7 days after the previous culture. RESULTS: Over a 46-month period, 526 patients underwent 1,372 fiberoptic bronchoscopy procedures with BAL. Of these, 72% were male patients, 91% followed blunt injury, and mean age and Injury Severity Score were 43 years and 30, respectively. Overall mortality was 14%. There were 1,898 organisms identified (42% were gram-positive and 58% were gram-negative). VAP was diagnosed in 38% of BAL. Overall, there were 43 episodes in 38 patients defined as false-negative (3%). The false-negative rate was 9% in patients with 10 organisms. The most common false-negative organisms were Pseudomonas and Acinetobacter species. CONCLUSION: The VAP diagnostic threshold for quantitative BAL in trauma patients should be >10 colonies/mL. One may consider a threshold of >10 colonies/mL in severely injured patients with Pseudomonas or Acinetobacter species.

Adult↗
PubMed2004

Use of presumptive antibiotics following tube thoracostomy for traumatic hemopneumothorax in the prevention of empyema and pneumonia--a multi-center trial.

OBJECTIVE: To determine whether presumptive antibiotics reduce the risk of empyema or pneumonia following tube thoracostomy for traumatic hemopneumothorax. METHODS: A prospective, randomized, double-blind trial was performed comparing the use of cefazolin for duration of tube thoracostomy placement (Group A) versus 24 hours (Group B) versus placebo (Group C). RESULTS: A total of 224 patients received 229 tube thoracostomies. Logistic regression analysis revealed that duration of tube placement and thoracic acute injury score were predictive of empyema (p <0.05). Empyema tended to occur more frequently in patients with penetrating injuries (p=0.09). chi analysis showed pneumonia occurred significantly more frequently in blunt than penetrating injuries (p <0.05). Presumptive antibiotic use did not significantly effect the incidence of empyema or pneumonia, although no empyemas occurred in Group A. CONCLUSIONS: The incidence of empyema was low and the use of presumptive antibiotics did not appear to reduce the risk of empyema or pneumonia.

Adolescent↗
PubMed2004

Apoptosis and necrosis in the development of acute lung injury after hemorrhagic shock.

Acute lung injury can be a complication of hemorrhagic shock. Mechanisms of injury include neutrophil-derived inflammatory products that induce necrosis within the lung. Recent data has shown apoptosis, in addition to necrosis, as a pathway leading toward acute lung injury in shock models. This study quantitates apoptotic and necrotic cells in the lung after hemorrhagic shock. Mongrel pigs (20-30 kg) under general anesthesia (with pancuronium and pentobarbital) underwent instrumentation with placement of carotid and external jugular catheters. The animals were randomized to sham hemorrhage (n = 6) and to hemorrhagic shock (n = 7). The hemorrhagic shock group then underwent hemorrhage (40-45% blood volume) to a systolic blood pressure of 40-50 mm Hg for 1 hour. The animals were then resuscitated with shed blood plus crystalloid to normalization of heart rate and blood pressure. The animals were observed under general anesthesia for 6 hours after resuscitation, then sacrificed, and lungs were harvested. Lung injury parameters including histology (H&E stain), apoptosis [terminal deoxynucleotidyl transferase-mediated dUTP biotin nick end labeling (TUNEL)], and myeloperioxidase activity (spectrophotometric assay) were assessed. Hemorrhagic shock induced marked loss of lung architecture, neutrophil infiltration, alveolar septal thickening, hemorrhage, and edema in H&E staining. Furthermore, MPO activity, a marker for neutrophil infiltration and activation, was more than doubled as compared to controls (44.0 vs 20.0 Grisham units activity/g). Apoptosis (cell shrinkage, membrane blebbing, apoptotic bodies) and necrosis (cellular swelling, membrane lysis) in neutrophils, macrophages, as well as in alveolar cells was demonstrated and quantified by H&E staining use. Apoptosis was confirmed and further quantified by positive TUNEL signaling via digital semiquantitative analysis, which revealed a significant increase in apoptotic cells (16.0 vs 2.5 cells/hpf, shock vs control, respectively) and necrotic cells (16.0 vs 2.0 cells/hpf, shock vs control, respectively). Acute lung injury is a complex pathophysiologic process. Apoptosis in cells (neutrophils, macrophages, alveolar cells) is induced within the lung after hemorrhagic shock. The role of apoptosis in pulmonary dysfunction after hemorrhagic shock has yet to be determined.

Animals↗
PubMed2003

Tetracyclines for treating multidrug-resistant Acinetobacter baumannii ventilator-associated pneumonia.

OBJECTIVE: To report the use of tetracyclines for the treatment of multidrug-resistant Acinetobacter baumannii ventilator-associated pneumonia (VAP). DESIGN: Observational case series. SETTING: . The Presley Regional Trauma Center located within the Regional Medical Center, Memphis, Tennessee, USA. PATIENTS AND PARTICIPANTS: Seven critically ill trauma patients with VAP caused by A. baumannii isolates that were resistant to all antibiotics tested except for doxycycline or minocycline. INTERVENTIONS: Patients were treated with IV doxycycline or minocycline for an average of 13.5 (range 9-20) days. MEASUREMENTS AND RESULTS: Doxycycline or minocycline was successful in six of seven patients. CONCLUSIONS: Doxycycline or minocycline may be effective for treating multidrug-resistant A. baumannii VAP.

APACHE↗
PubMed2003

Current management of colon trauma.

This article offers a comprehensive review of colon trauma from World War I to the present. The process of evidence-based medicine was used to analyze the data from the past 25 years and define standards of care in the field. Where data are less compelling, recommendations and suggestions are provided for future research. Topics highlighted include destructive and nondestructive colon injuries, rectal injuries, on-table colonic lavage, colonic bypass tubes, risk factors, perioperative antibiotics, and colostomy closure.

Anastomosis, Surgical↗
PubMed2003

Recollections of Robert M. Zollinger, M.D.

Remembering Dr. Robert M. Zollinger are Dr. Larry C. Carey, professor of surgery at the University of South Florida, in Tampa, Florida; Dr. Dan W. Elliott, professor emeritus of surgery at Wright State University, in Dayton, Ohio; Dr. E. Christopher Ellison, the Robert M. Zollinger professor and chairman of surgery at Ohio State University, in Columbus, Ohio; Dr. Timothy C. Fabian, professor and chairman of surgery at the University of Tennessee, in Memphis, Tennessee; and Mrs. Letitia Roberts, the widow of Dr. Stuart S. Roberts, the first recipient of the Zollinger Chair of Surgery at Ohio State, of Peoria, Illinois.

General Surgery↗
PubMed2003

Cerebral perfusion pressure directed therapy following traumatic brain injury and hypotension in swine.

There is a paucity of studies, clinical and experimental, attesting to the benefit of cerebral perfusion pressure (CPP) directed pressor therapy following traumatic brain injury (TBI). The current study evaluates this therapy in a swine model of TBI and hypotension. Forty-five anesthetized and ventilated swine received TBI followed by a 45% blood volume bleed. After 1 h, all animals were resuscitated with 0.9% sodium chloride equal to three times the shed blood volume. The experimental group (PHE) received phenylephrine to maintain CPP > 80 mm Hg; the control group (SAL) did not. Outcomes in the first phase (n = 33) of the study were as follows: cerebro-venous oxygen saturation (S(cv)O(2)), cerebro-vascular carbon dioxide reactivity (DeltaS(cv)O(2)), and brain structural damage (beta-amyloid precursor protein [betaAPP] immunoreactivity). In the second phase (n = 12) of the study, extravascular blood free water (EVBFW) was measured in the brain and lung. After resuscitation, intracranial and mean arterial pressures were >15 and >80 mm Hg, respectively, in both groups. CPP declined to 64 +/- 5 mm Hg in the SAL group, despite fluid supplements. CPP was maintained at >80 mm Hg with pressors in the PHE group. PHE animals maintained better S(cv)O(2) (p < 0.05 at 180, 210, 240, 270, and 300 min post-TBI). At baseline, 5% CO(2) evoked a 16 +/- 4% increase in S(cv)O(2), indicating cerebral vasodilatation and luxury perfusion. By 240 min, this response was absent in SAL animals and preserved in PHE animals (p < 0.05). Brain EVBFW was higher in SAL animals; however, lung EVBFW was higher in PHE animals. There was no difference in betaAPP immunoreactivity between the SAL and PHE groups (p > 0.05). In this swine model of TBI and hypotension, CPP directed pressor therapy improved brain oxygenation and maintained cerebro-vascular CO(2) reactivity. Brain edema was lower, but lung edema was greater, suggesting a higher propensity for pulmonary complications.

Animals↗
PubMed2003

Staged management of giant abdominal wall defects: acute and long-term results.

INTRODUCTION: Shock resuscitation leads to visceral edema often precluding abdominal wall closure. We have developed a staged approach encompassing acute management through definitive abdominal wall reconstruction. The purpose of this report is to analyze our experience with this technique applied to the treatment of patients with open abdomen and giant abdominal wall defects. METHODS: Our management scheme for giant abdominal wall defects consists of 3 stages: stage I, absorbable mesh insertion for temporary closure (if edema quickly resolves within 3-5 days, the mesh is gradually pleated, allowing delayed fascial closure); stage II, absorbable mesh removal in patients without edema resolution (2-3 weeks after insertion to allow for granulation and fixation of viscera) and formation of the planned ventral hernia with either split thickness skin graft or full thickness skin closure over the viscera; and stage III, definitive reconstruction after 6-12 months (allowing for inflammation and dense adhesion resolution) by using the modified components separation technique. Consecutive patients from 1993 to 2001 at a single institution were evaluated. Outcomes were analyzed by management stage, with emphasis on wound related morbidity and mortality, and fistula and recurrent hernia rates. RESULTS: Two hundred seventy four patients (35 with sepsis, 239 with hemorrhagic shock) were managed. There were 212 males (77%), and mean age was 37 (range, 12-88). The average size of the defects was 20 x 30 cm. In the stage I group, 108 died (92% of all deaths) because of shock. The remaining 166 had temporary closure with polyglactin 910 woven absorbable mesh. As visceral edema resolved, bedside pleating of the absorbable mesh allowed delayed fascial closure in 37 patients (22%). In the stage II group, 9 died (8% of all deaths) from multiple organ failure associated with their underlying disease process, and 96% of the remaining 120 had split-thickness skin graft placed over the viscera. No wound related mortality occurred. There were a total of 14 fistulae (5% of total, 8% of survivors). In the stage III group, to date, 73 of the 120 have had definitive abdominal wall reconstruction using the modified components separation technique. There were no deaths. Mean follow-up was 24 months, (range 2-60). Recurrent hernias developed in 4 of these patients (5%). CONCLUSIONS: The staged management of patients with giant abdominal wall defects without the use of permanent mesh results in a safe and consistent approach for both initial and definitive management with low morbidity and no technique-related mortality. Absorbable mesh provides effective temporary abdominal wall defect coverage with a low fistula rate. Because of the low recurrent hernia rate and avoidance of permanent mesh, the components separation technique is the procedure of choice for definitive abdominal wall reconstruction.

Abdominal Injuries↗
PubMed2003

Novel resuscitation strategy for pulmonary contusion after severe chest trauma.

BACKGROUND: Adenosine A2a receptor stimulation can increase coronary perfusion and also reduce leukocyte-mediated inflammatory responses in some conditions. Hextend is a novel colloid solution that may have antioxidant properties. All these actions might be beneficial after severe chest trauma, but have never been investigated. To fill these gaps, this study evaluated the therapeutic potential of a novel adenosine A2a agonist during fluid resuscitation from severe chest trauma with either standard-of-care crystalloid or Hextend. METHODS: Anesthetized, ventilated swine received unilateral, blunt trauma to the right chest via captive bolt gun, followed by a 10- to 12-mL/kg arterial hemorrhage. After 25 minutes of shock, ATL-146e was started (10 ng/kg/min intravenously for 180 minutes). After an additional 5 minutes, the minimum amount of either colloid (Hextend, 5% hetastarch in lactate-buffered, balanced electrolyte solution) or crystalloid (lactated Ringer's [LR] solution) was administered to maintain mean arterial pressure > 70 mm Hg and heart rate < 100 beats/min and to correct lactate for 180 minutes postinjury. Cardiopulmonary function was monitored and serial bronchoalveolar lavage samples were analyzed for protein, leukocyte infiltration, and expression of cyclooxygenase (COX)-1 and COX-2 isozymes as markers of the inflammatory cascade. RESULTS: Fluid requirements were reduced by half with Hextend compared with LR (p < 0.05). ATL-146e in either Hextend or LR transiently increased cardiac output, cardiac contractility, and systemic oxygen delivery (all p < 0.05). Pao(2)/Fio(2) ratio was 50 to 100 higher and bronchoalveolar lavage leukocytes were reduced by half with Hextend versus LR (both p < 0.05), but there was no added effect of ATL-146e. COX-1 expression was induced in macrophages (Mphis), whereas COX-2 was induced in neutrophils. Neither Hextend nor ATL-146e reduced COX expression. CONCLUSION: Hextend reduced the volume for initial resuscitation, which may offer logistical advantages in prehospital field conditions or whenever there is limited medical resources or prolonged transport times; ATL-146e improved early cardiac performance without causing hypotension or bradycardia; when administered 25 to 30 minutes after injury, neither Hextend nor ATL-146e altered inflammatory changes in pulmonary Mphis or infiltrating PMNs; and further studies are needed to determine whether these short-term benefits correlate with long-term outcome.

Animals↗
PubMed2003

Expedited discharge in trauma patients requiring anticoagulation for deep venous thrombosis prophylaxis: the LEAP Program.

OBJECTIVE: With rising health care costs, methods to decrease length of hospital stay without compromising care are necessary. One area that extends length of stay in trauma patients is inpatient anticoagulation to a therapeutic international normalized ratio. The 1998 American College of Chest Physicians guidelines recommend thromboprophylaxis with low-molecular-weight heparin (LMWH) and oral warfarin in this population. The LMWH Expedited Anticoagulation Program (LEAP) was created with the following goals: to decrease the number of inpatient warfarin days and to reduce overall number of hospital days. METHODS: Inpatient anticoagulation was initiated with warfarin and LMWH. LEAP included early multidisciplinary collaboration to ensure third-party approval, outpatient primary care physician follow-up, and LMWH self-injection before discharge. Patients were discharged on LMWH (discontinued by primary care provider when a therapeutic international normalized ratio was attained) and warfarin (continued until resolution of orthopedic injuries). From August 2000 to August 2001, adult patients were included in the prospective study. Primary inclusion criteria were blunt acetabular fracture, bilateral lower extremity fracture, and contralateral upper and lower extremity fractures. Patients with similar injuries receiving warfarin for deep venous thrombosis prophylaxis between June 1999 and June 2000 were the control population. Anticoagulation care was similar for the study and control subjects. RESULTS: There were 182 patients evaluated for LEAP inclusion. After initial evaluation, 108 patients were enrolled in LEAP (Injury Severity Score of 13). There were 69 control subjects (Injury Severity Score of 13). The average number of inpatient warfarin days was decreased from 8.8 days to 5.0 days in the control and study populations, respectively (p < 0.0001). The average length of hospitalization was shortened from 17.3 days in the control group to 12.9 days in the study (LEAP) population (p < 0.002). CONCLUSION: LEAP has successfully decreased the number of inpatient days on warfarin and total hospital days for trauma patients requiring deep venous thrombosis prophylaxis. These results have substantially decreased health care costs and increased available hospital beds in this era of high hospital occupancy.

Adult↗
PubMed2003

A formula for prediction of posttraumatic pneumonia based on early anatomic and physiologic parameters.

BACKGROUND: Identification of risks for development of ventilator-associated pneumonia (VAP), which might be identified early after injury, would allow for prognostic estimates and targeting of high-risk cohorts for clinical trials of preventive strategies. This study was performed to develop an equation that can be applied to estimate the probability of pneumonia based on parameters collected in the early postinjury interval. METHODS: Over a 28-month period, patient admissions were reviewed for mechanism and severity of injury, patterns of injury, shock, and need for emergent intubation. Early deaths (<48 hours) were excluded. VAP diagnosis required > or = 10(5) colony-forming units/mL organisms in the bronchoalveolar lavage effluent. Multiple logistic regression analysis was used to develop the prediction equation and estimate odds ratios. The equation was then tested on consecutive patients admitted over a 2-month period. RESULTS: We reviewed 9,721 admissions (77% blunt, 23% penetrating). VAP incidence was 5.6%. Overall mortality was 2% (21% for patients with VAP vs. 1% for no VAP; p < 0.0001). Multiple logistic regression analysis for all patients produced the following equation: f(x) = -3.08 - 1.56 (MOI) - 0.12 (GCS) + 1.37 (SCI) + 0.30 (chest AIS) + 1.87 (lap) + 0.67 (tx) + 0.05 (ISS) + 0.66 (int), where MOI is mechanism of injury (penetrating = 1, blunt = 0), GCS is Glasgow Coma Scale score, SCI is spinal cord injury (yes = 1, no = 0), lap is emergent laparotomy (yes = 1, no = 0), ISS is Injury Severity Score, tx is units of blood transfused in the resuscitation room, and int is intubation in either the field or the resuscitation room (yes = 1, no = 0). The probability of VAP was calculated as follows: P(VAP) = e(f)(x)/1 + e(f)(x). This formula was concordant in 95% and discordant in 5%. CONCLUSION: It is possible to accurately predict risk for VAP in trauma patients based on data available early after injury. This calculation could be useful for counseling families relative to prognosis and research protocols, and addressing hospitalization issues with third-party payors.

Adult↗
PubMed2003

Resuscitation with a novel hemoglobin-based oxygen carrier in a Swine model of uncontrolled perioperative hemorrhage.

BACKGROUND: Systemic and pulmonary hypertension, possibly related to nitric oxide scavenging by free hemoglobin (Hb), is often seen during resuscitation with hemoglobin-based oxygen carriers (HBOCs). Recently, a second-generation HBOC, rHb2.0 for Injection (rHb), has been developed using recombinant human Hb that has reduced reactivity with nitric oxide. The current study evaluates the efficacy of this novel compound for resuscitation in a swine model of uncontrolled perioperative hemorrhage. METHODS: After instrumentation, animals underwent splenectomy and rapid hemorrhage to a systolic blood pressure of 35 mm Hg and isoelectric electroencephalography. 15 minutes of shock was followed by resuscitation over 30 minutes. In phase I, 18 animals were randomized into three resuscitation groups: (1) lactated Ringer's (LR) equal to three times the shed blood, the negative control group; (2) heterologous blood (BL) equal to Hb 2 g/kg, the positive control group; and (3) rHb equal to 2 g/kg, the treatment group. In phase II, six animals underwent the same experiment with a first-generation HBOC, diaspirin cross-linked Hb (DCLHb) equal to 2 g/kg, an additional control group. On day 0 after 2 hours of observation, spontaneously breathing animals were returned to their cages. Surviving animals were redosed on days 1, 2, and 3 (rHb/DCLHb 1 g/kg; LR/BL-LR 500 mL). Survivors were killed on day 5 and organs harvested for histologic examination. Group comparisons were performed using Student's t test, repeated-measures analysis of variance, and chi2 test. Significance was set at 95% confidence intervals. RESULTS: After resuscitation, systemic mean arterial pressure (MAP) (baseline = 107 +/- 15 mm Hg) was 128 +/- 34 and 108 +/- 15 mm Hg in rHb and BL animals, respectively, and remained stable. In LR and DCLHb animals, after normalization, MAP declined to 67 +/- 13 and 84 +/- 34 mm Hg, respectively. The rHb group maintained higher MAP than the LR and BL groups (p < 0.05 vs. both). With resuscitation, mean pulmonary arterial pressure (PAP) (baseline = 25 +/- 5 mm Hg) increased in rHb (40 +/- 4 mm Hg), BL (34 +/- 3 mm Hg), and DCLHb (40 +/- 3 mm Hg) groups, but stayed elevated only in the DCLHb group (36 +/- 3 mm Hg). PAP in the rHb group was similar to the BL group (p > 0.05), and both rHb and BL groups showed a higher PAP than the LR group (p < 0.05 vs. both). PAP was highest in the DCLHb group (p < 0.05 vs. rHb). Cardiac output of rHb and BL groups was similar (p > 0.05) throughout the observation period. Arterial lactate increased to 5.6 +/- 2.5 mmol/L with shock and then normalized to < 2.0 mmol/L in the rHb, BL, and LR groups within 30 minutes of resuscitation. It remained elevated to > 3.5 mmol/L and showed a delayed increase in the DCLHb group (p < 0.05). Causes and number of deaths were as follows: rHb, zero of six; BL-transfusion reaction, one of six; LR-irreversible shock, four of six; and DCLHb-ventricular failure, six of six. There was no significant increase in plasma methemoglobin (rHb) and no difference in liver or cardiac enzymes (rHb vs. BL). No histologic abnormalities were seen in the rHb group except for cytoplasmic vacuolation, a process thought to be related to metabolism of the test article. CONCLUSION: rHb2.0 for Injection, a second-generation recombinant human HBOC, performs as well as heterologous blood for resuscitation after perioperative blood loss, does not cause sustained pulmonary hypertension, maintains adequate cardiac output and oxygen delivery, and is superior to either LR or DCLHb.

Animals↗
PubMed2003

Multiplicity of solid organ injury: influence on management and outcomes after blunt abdominal trauma.

OBJECTIVE: The current study was undertaken to examine how concomitant injury to liver and spleen after blunt abdominal trauma affects management and outcomes. METHODS: This study was a retrospective chart review of all blunt abdominal trauma patients admitted with a diagnosis of liver or spleen injury at two Level I trauma centers over a 4-year period. Presentation, injury grade, management, and outcomes were analyzed. Patients with single-organ injury (liver or spleen) were compared with patients having injury to both organs (liver and spleen). Significance was set at 95% confidence intervals. RESULTS: Of 1,288 patients who met entry criteria, 1,125 had single (spleen, 573; liver, 552) organ injury (group S) and 163 had injury to both organs (group B). Group B patients had significantly higher Injury Severity Score, higher admission lactate, and lower admission systolic blood pressure and base excess. Eighty-one percent (915 of 1,125) of group S and 69% (112 of 163) of group B patients were managed nonoperatively (p < 0.05). Of the nonoperatively managed patients, 5.8% (53 of 915) in group S and 11.6% (13 of 112) in group B failed this form of therapy (p < 0.05). Higher failure rate in group B was because of bleeding from injured solid organ(s), and not non-solid organ related failures. Mortality, intensive care unit and hospital lengths of stay, and transfusion requirements were all significantly higher in group B. CONCLUSION: Blunt trauma patients with concomitant injury to liver and spleen have higher Injury Severity Score, mortality, lengths of stay, and transfusion requirements. There is a higher failure rate with nonoperative management, and therefore extra vigilance is warranted when choosing this form of therapy in the presence of injury to both organs.

Abdominal Injuries↗
PubMed2003

The predictive value of preliminary bacterial colony counts from bronchoalveolar lavage in critically ill trauma patients.

A common strategy for the diagnosis of ventilator-associated pneumonia (VAP) includes quantitative cultures from bronchoalveolar lavage (BAL). Often, empiric antibiotic therapy is initiated and continued until the final culture report. However, approximately 60 per cent of BAL cultures rule out VAP. Preliminary BAL results, obtained earlier, may identify these patients and allow early discontinuation of empiric antibiotics. This is desirable because unnecessary antibiotic therapy results in increased bacterial resistance, adverse drug events, and increased costs. The purpose of this study was to determine the value of preliminary BAL results for predicting final BAL results. A total of 1579 isolates from 868 BAL cultures over a 3-year period were analyzed. Preliminary and final colony counts for each isolate were categorized as either no growth (NG), insignificant (1-99,999 cfu/mL), or significant (> or = 100,000 cfu/mL). Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of preliminary results were calculated based on individual isolates and individual BAL samples. The presence of concurrent antibiotic therapy was collected for all false-negative isolates. On preliminary report, there were 367 isolates with NG, 820 isolates with insignificant growth, and 392 isolates with significant growth. Overall preliminary culture results had a sensitivity of approximately 90 per cent and specificity of >90 per cent for the presence of VAP. Preliminary culture results accurately predicted the presence or absence of VAP in 838 (96.5%) of the BALs performed. Individual isolates and BAL samples with insignificant preliminary growth had greater reliability in predicting the absence of VAP than those with NG. There was no difference in the number of false-negative isolates that were taken while concurrent antibiotic therapy was present between insignificant and NG groups. Preliminary culture results yielding either insignificant or significant growth are highly predictive for final colony counts of similar magnitude. BALs with preliminary results demonstrating no growth are not as reliable. Isolates with significant preliminary growth should be considered clinically important, and antibiotic therapy should be changed, if necessary, to target such organisms. Isolates with insignificant preliminary growth have a low rate of false negatives; therefore, empiric antibiotic therapy specific for such organisms could be discontinued before obtaining final results. Empiric antibiotics should be continued until the final results are available in those patients with NG BALs.

Adult↗
PubMed2002

Risk factors for late-onset nosocomial pneumonia caused by Stenotrophomonas maltophilia in critically ill trauma patients.

Patients with nosocomial pneumonia caused by Stenotrophomonas maltophilia often receive inadequate empiric antibiotic therapy, potentially increasing mortality. Knowledge of the risk factors associated with S. maltophilia pneumonia may better guide the selection of empiric antibiotic therapy. Potential risk factors for S. maltophilia pneumonia were retrospectively analyzed for critically ill trauma patients with late-onset gram-negative pneumonia. The effects of S. maltophilia infection and inadequate empiric antibiotic therapy on patient outcomes were also assessed. By multivariate analysis, S. maltophilia pneumonia was found to be associated with cefepime exposure and tracheostomy in patients with a single pneumonia episode and with higher Injury Severity Score and pulmonary contusion in patients with multiple pneumonia episodes. S. maltophilia pneumonia was associated with increased patient morbidity; only inadequate empiric antibiotic therapy was associated with a higher mortality rate. In critically ill trauma patients with late-onset ventilator-associated pneumonia and these risk factors, empiric antibiotic therapy should include agents active against S. maltophilia.

Adult↗
PubMed2002

Comparison of ampicillin-sulbactam and imipenem-cilastatin for the treatment of acinetobacter ventilator-associated pneumonia.

Acinetobacter organisms, which are a common cause of ventilator-associated pneumonia (VAP) in some health care centers, are becoming more resistant to such first-line agents as imipenem-cilastatin (Imi-Cil). Sulbactam has good in vitro activity against Acinetobacter organisms; thus, ampicillin-sulbactam (Amp-Sulb) may be a viable treatment alternative. The outcomes for critically ill trauma patients with Acinetobacter VAP treated with either Amp-Sulb or Imi-Cil were compared retrospectively. A total of 77 episodes in 75 patients were studied. Fourteen patients were treated with Amp-Sulb, and 63 patients were treated with Imi-Cil. Treatment efficacy was similar in the Amp-Sulb and Imi-Cil groups (93% vs. 83%, respectively; P>.05). No statistically significant differences between groups were noted with regard to associated mortality, duration of mechanical ventilation, or length of stay in the intensive care unit or hospital. However, adjunctive aminoglycoside therapy was used more often in the Amp-Sulb group. Patients generally received Amp-Sulb because of imipenem resistance. Amp-Sulb was effective in treating a small number of patients with Acinetobacter VAP; however, more data are needed.

Acinetobacter↗