Search PubMed⌕ Search

Biomedical subjects

F A Moore

Publications and source records attributed to F A Moore.

At least 127 records · Page 7Linked to original sources
PubMed1993

Diagnosing pneumonia in mechanically ventilated trauma patients: endotracheal aspirate versus bronchoalveolar lavage.

We prospectively investigated the diagnostic value of semiquantitative (semiQC) and quantitative (QC) cultures of endotracheal aspirate (ETA) compared with QC of bronchoalveolar lavage (BAL) fluids in 18 mechanically ventilated trauma patients with clinical signs of pneumonia. The general agreement between QC of ETA and BAL was 89% when conventional cutoffs for the QC were used and 94% if the cutoffs were adjusted for previous antibiotic therapy. In all six patients whose clinical diagnoses of pneumonia were considered definite, both QC of ETA and QC of BAL were positive; however, standard semiQC of ETA showed comparable results in this group. On the contrary, in the 12 patients whose clinical diagnoses were uncertain, QC of BAL and ETA were negative in ten patients and in five (50%) of these, pneumonia was eventually excluded. Semiquantitative cultures of ETA were positive in all these patients. Five (28%) patients experienced a decrease in PaO2/FiO2 (> 15% of previous value) 2 hours after BAL, and in three (17%) this derangement persisted for 24 hours. These data suggest that BAL may be hazardous in mechanically ventilated trauma patients and that its use should be restricted to patients in whom the diagnosis is in doubt.

Adult↗
PubMed1993

Postinjury multiple organ failure: role of extrathoracic injury and sepsis in adult respiratory distress syndrome.

Adult respiratory distress syndrome (ARDS) and multiple organ failure (MOF) occur as a result of an unbridled systemic inflammatory response (i.e., severe systemic inflammatory response syndrome [SIRS]). Early epidemiologic studies concluded that infection with systemic sepsis was the common pathway for the development of ARDS and eventual MOF. As a consequence, research investigation from 1977 to 1987 focused on later clinical events (e.g., immunosuppression, persistent hypercatabolism, and bacterial translocation). Now, it is believed that an initial massive traumatic insult can create severe SIRS independent of infection (one-hit model). Alternatively, a less severe traumatic insult can create an inflammatory environment (i.e., primes the host) such that a later, otherwise innocuous, secondary inflammatory insult precipitates severe SIRS (two-hit model). As a result of these newer inflammatory models, research interest over the last 5 yrs has shifted to investigating earlier clinical events (e.g., unrecognized flow-dependent oxygen consumption, ischemia/reperfusion, and priming/activation of the inflammatory response). The traditional infection models of ARDS and MOF are applicable to current research and patient care efforts. However, the inflammatory models emphasize the pivotal role of the initial traumatic insult. Moreover, while ARDS occurs earlier than other types of overt organ failure, it is now believed that simultaneous organ injury is occurring, presumably via similar inflammatory mechanisms.

Adult↗
PubMed1993

Platelet-activating factor-induced polymorphonuclear neutrophil priming independent of CD11b adhesion.

BACKGROUND: Our previous studies have implicated phospholipase A2-dependent platelet-activating factor (PAF) production in the genesis of polymorphonuclear neutrophil (PMN)-mediated tissue injury after gut ischemia-reperfusion. Further, these studies have suggested a discordance of PMN sequestration and tissue injury. CD11B-dependent PMN-endothelial cell adhesion has been purported to play a dominant role in PMN-mediated tissue injury. We therefore undertook this study with the hypothesis that PAF-induced PMN superoxide production requires CD11B-mediated PMN-endothelial cell adherence. METHODS: Human PMNs, isolated by Percoll gradient centrifugation, were exposed to PAF (10 ng/ml). At fixed times of exposure during 120 minutes, (1) superoxide production, (2) CD11B receptor expression, and (3) PMN adhesion to unstimulated human umbilical vein endothelial cell cultures were assayed. RESULTS: PAF induced prompt changes in PMN priming (increased superoxide production after N-formyl-methyl-leucyl-phenylalanine activation), adhesion to unstimulated endothelial cells, and CD11B receptor expression. Priming was temporally concordant with the rise and fall of CD11B expression but appeared to precede adhesion. CD11B blockade (F(Ab') 2 anti-CD11B [60.1] antibodies), before or at maximal PAF priming, reduced PMN adhesion but had no effect on superoxide production. CONCLUSIONS: In summary, PAF-induced PMN priming occurs in temporal concordance with the expression of CD11B and subsequent endothelial cell adherence, but CD11B-mediated adherence is not essential for this process.

Cell Adhesion↗
PubMed1993

Intravascular ultrasonography for the diagnosis of traumatic aortic disruption: a case report.

Thoracic aortic disruptions after blunt trauma are highly lethal injuries. Diagnosis of these injuries has traditionally been based on clinical suspicion, chest radiographs, and aortography. The roles of dynamic computed tomography and transesophageal echocardiography are currently under investigation. Intravascular ultrasonography is a new technology with potential as a diagnostic adjunct in the evaluation of these injuries. We present a case of traumatic aortic disruption identified by intravascular ultrasonography after nondiagnostic aortography and dynamic computed tomography studies.

Accidents, Traffic↗
PubMed1993

Fivefold enlargement of implants in a splenic autotransplant recipient.

A 30-year-old patient underwent splenectomy for trauma with splenic autotransplantation. Four years later he survived a bout of pneumococcal sepsis with only oral penicillin therapy. Seven years after splenectomy, he underwent another laparotomy with the finding of fivefold enlargement of the splenic implants. Splenic autotransplants enlarge and probably function in human beings.

Adult↗
PubMed1992

Liver injury is a reversible neutrophil-mediated event following gut ischemia.

The purposes of this study were to characterize the temporal relationship of distant organ dysfunction after mesenteric ischemia/reperfusion (I/R), and to ascertain if the neutrophil is critical to this process. Normal and neutrophil-depleted rats (vinblastine sulfate, 0.75 mg/kg intravenously) underwent 45 minutes of superior mesenteric artery occlusion and after 0, 6, and 18 hours of reperfusion, blood was sampled and liver and lungs were harvested. Iodine 125 albumin leak was used as a marker for pulmonary and liver injury, and serum acetoacetate/3-hydroxybutyrate (AcAc/3-OHB) was used as an index of hepatic mitochondrial redox state. Gut I/R at 6 hours increased 125I-albumin lung/blood ratio (gut I/R, 0.077 +/- 0.006; control, 0.045 +/- 0.004) and 125I-albumin liver/blood ratio (gut I/R, 0.120 +/- 0.007; control, 0.077 +/- 0.003), while AcAc/3-OHB decreased significantly (gut I/R, 0.420 +/- 0.040; control, 0.880 +/- 0.120). Neutrophil depletion eliminated these changes at 6 hours (blood AcAc/3-OHB, 0.720 +/- 0.100; 125I liver/blood, 0.068 +/- 0.006; 125I lung/blood, 0.046 +/- 0.007). We conclude the following: (1) intestinal I/R produces simultaneous liver and lung injury; (2) injury was present at 6 hours but is reversed at 18 hours; and (3) the I/R-induced liver and lung injuries were neutrophil mediated.

Animals↗
PubMed1992

Postinjury shock and early bacteremia. A lethal combination.

Gut bacteria translocation has been invoked as a prime cause of early postinjury death. To examine this hypothesis, we obtained emergency department blood cultures in 132 acutely injured patients requiring urgent laparotomy for trauma. In the latter half of these patients, mesenteric lymph node and liver biopsy cultures were also performed. The incidence of early bacteremia was 11% (10/94) in the patients without shock compared with 32% (12/38) in the group with shock. The majority (73%) were gram-positive bacteremias. Most notably, Staphylococcus was isolated in 13% (5/38) of the patients with shock, but these isolates were of no apparent clinical significance. In contrast, 18% (7/38) of the patients with shock had enteric bacteremias, and all of these patients died. Cultures were positive in 11% of the liver samples and 15% of the mesenteric lymph nodes. With the exception of two patients with concurrent enteric bacteremias, these hepatic and mesenteric lymph node bacteria were of no clinical significance. In conclusion, bacterial translocation occurs infrequently, and virtually all enteric bacteria were found in dying patients; the cause or effect remains to be defined.

Adult↗
PubMed1992

Endotoxin after gut ischemia/reperfusion causes irreversible lung injury.

We have recently reported that 45 min of gut ischemia causes moderate 125I-albumin lung leak at 6 hr of reperfusion which was reversed at 18 hr. Our purpose was to determine the effect of a second insult, low dose endotoxin (LPS, 2.5 mg/kg), given 6 hr after gut ischemia/reperfusion (I/R) on this lung injury as assessed by 125I-albumin leak, neutrophil influx (myeloperoxidase assay, MPO), histopathology, and mortality. Rats were randomized to either sham laparotomy (LAP) or 45 min of superior mesenteric artery occlusion and 6 hr later were treated with LPS or saline. At 18 hr reperfusion the lungs were harvested, assayed for 125I-albumin leak and MPO, and microscopically examined by an unbiased observer after routine H&E staining. We observed that LPS increased lung neutrophil levels both with or without gut I/R. However, only the combined insult (I/R + LPS) increased 125I-albumin leak at 18 hr of reperfusion. Lung histology confirmed that the sequential combination of I/R + LPS caused marked interstitial edema and neutrophil sequestration accompanied by alveolar edema, hemorrhage, and fibrinous exudate, while I/R or LAP + LPS did not. The mortality rate of I/R + LPS was 39% which was significantly higher than LAP alone (0%), gut I/R alone (0%), or LAP + LPS (4%). In conclusion, a delayed exposure to low dose endotoxin converts moderate gut I/R-induced lung dysfunction into advanced organ failure.

Albumins↗
PubMed1992

Gut and liver coordinated metabolic response following major torso injury.

Major trauma provokes a stress response which is mediated, in part, via glucagon, catecholamines, and cortisol. These stress hormones modulate the choice of energy substrate for various tissues. While glucose and fatty acids are considered the preferred fuels, ketone bodies (26/ATP/mole) may be a viable alternative. In this study, we measured the concentrations of acetoacetate and beta-hydroxybutyrate (3-OHB) in the portal as well as systemic circulations of 10 critically injured patients (revised trauma score = 6.8 +/- 0.5, injury severity score = 27 +/- 3) during the first 5 postoperative days. At 6 hr postinjury, 3-OHB was elevated in the portal system (0.34 +/- 0.01 mM) while depressed systemically (0.09 +/- 0.02 mM), indicating that the gut was capable of ketogenesis. In contrast, at 24 hr, 3-OHB rose systemically (0.39 +/- 0.02 mM) while decreasing in portal blood (0.09 +/- 0.01 mM) implying gut ketone consumption. Moreover, the systemic ketone body ratio became elevated at 24 hr, suggesting an enhanced liver energy status. In summary, we believe ketogenesis is stimulated by major trauma. Initially, the gut supports ketone concentration in the systemic circulation, whereas, by 24 hr, the gut becomes a ketone consumer and the liver maintains circulating levels.

Abdominal Injuries↗
PubMed1992

Gut ischemia/reperfusion-induced liver dysfunction occurs despite sustained oxygen consumption.

We have previously shown that gut ischemia/reperfusion (I/R) causes liver dysfunction in vivo (increased [I125]albumin leak, decreased mitochondrial redox potential). Our purpose was to investigate liver dysfunction due to gut I/R in an ex vivo model where oxygen delivery (DO2) could be controlled. Rats underwent laparotomy (sham) or 45 min of superior mesenteric artery (SMA) occlusion (I/R) and 6 hr later the gut and liver were isolated in situ. Pressures were monitored while recirculating blood was perfused via the hepatic artery (2.5 ml/min) for 90 min and the SMA (7.5 ml/min) for the first 30 min, then the portal vein (7.5 ml/min) for 60 min. Both gut and liver DO2 and VO2 (Fick method) were maintained throughout the study period in the gut I/R as well as sham groups. Despite maintenance of liver VO2, however, gut I/R resulted in a marked and persistent reduction in bile flow. In conclusion, dysfunctional bile production after gut I/R is not due to impaired VO2, but rather gut-liver signaling yet to be defined.

Animals↗
PubMed1992

Efficacy of selective intrabronchial air insufflation in acute lobar collapse.

Flexible fiberoptic bronchoscopy (FFB) to remove mucous plugs followed by selective intrabronchial air insufflation (SII) to expand the atelectatic lung was used in 17 surgical intensive care unit (SICU) patients with pulmonary lobar collapse. Thirteen patients were admitted for acute trauma, and the remainder were elderly postoperative patients. Lobar collapses occurred on SICU days 1 to 18 (mean +/- SEM: 5 +/- 1 days), and duration ranged from 4 to 258 hours (mean: 77 +/- 18 hours). Indications for FFB with SII included critical hypoxemia in 5 patients, worsening collapse in 2, and failure to respond to aggressive respiratory care in 10 (59%). FFB with SII was effective in 14 (82%) patients: 10 achieved full lung re-expansion, and 4 partial lung re-expansion. When lobar collapse was of less than 72 hours' duration, 92% (12 of 13) of patients had lungs re-expanded compared with 50% (2 of 4) whose collapse existed for more than 72 hours. The mean PaO2/FIO2 (fraction inspired oxygen) ratio was 135 +/- 18 prior to FFB with SII and increased to 205 +/- 21 after FFB with SII. Complications were minor and clinically insignificant. In conclusion, SII appears to be a simple, safe, effective adjunct to FFB in the treatment of SICU patients with pulmonary lobar collapse.

Acute Disease↗
PubMed1992

Early enteral feeding, compared with parenteral, reduces postoperative septic complications. The results of a meta-analysis.

This two-part meta-analysis combined data from eight prospective randomized trials designed to compare the nutritional efficacy of early enteral (TEN) and parenteral (TPN) nutrition in high-risk surgical patients. The combined data gave sufficient patient numbers (TEN, n = 118; TPN, n = 112) to adequately address whether route of substrate delivery affected septic complication incidence. Phase I (dropouts excluded) meta-analysis confirmed data homogeneity across study sites, that TEN and TPN groups were comparable, and that significantly fewer TEN patients experienced septic complications (TEN, 18%; TPN, 35%; p = 0.01). Phase II meta-analysis, an intent-to-treat analysis (dropouts included), confirmed that fewer TEN patients developed septic complications. Further breakdown by patient type showed that all trauma and blunt trauma subgroups had the most significant reduction in septic complications when fed enterally. In conclusion, this meta-analysis attests to the feasibility of early postoperative TEN in high-risk surgical patients and that these patients have reduced septic morbidity rates compared with those administered TPN.

Adult↗
PubMed1992

Simultaneous liver and lung injury following gut ischemia is mediated by xanthine oxidase.

We have previously shown that gut ischemia/reperfusion (I/R) causes simultaneous liver and lung dysfunction and that neutrophils play a critical role in this process. The purpose of this study was to ascertain whether xanthine oxidase (XO) was likewise operational. Normal and XO-inactivated rats (given a tungsten-enriched, molybdenum-depleted diet for 3 weeks) underwent 45 minutes of occlusion of the superior mesenteric artery, and control rats were subjected to a sham laparotomy. After zero and six hours of reperfusion, blood was sampled and livers and lungs harvested. Iodine-125-labeled albumin leak was used as a marker for pulmonary and liver capillary permeability barrier function, and serum acetoacetate/3-hydroxybutyrate (AcAc/3-OHB) levels as an index of hepatic mitochondrial redox state. Gut ischemia/six hours of reperfusion (I/R) increased the 125I albumin lung/blood ratio and the 125I albumin liver/blood ratio; AcAc/3-OHB levels decreased significantly. Xanthine oxidase activation eliminated the observed lung and liver capillary leak as well as the hepatic metabolic derangement induced by gut I/R. In conclusion, the simultaneous lung and liver dysfunction produced by gut I/R is mediated by XO.

Animals↗
PubMed1992

Incommensurate oxygen consumption in response to maximal oxygen availability predicts postinjury multiple organ failure.

Untreated flow-dependent oxygen consumption (VO2) has recently been implicated as an unrecognized risk factor for multiple organ failure (MOF). We therefore prospectively studied 39 severely injured patients with known risk factors for multiple organ failure who were subjected to an established resuscitation protocol aimed at maximizing oxygen delivery (DO2 greater than 600 mL/min.m2) to attain a VO2 goal of greater than 150 mL/min.m2. Fifteen (38%) of these high risk patients did not meet this VO2 goal by 12 hours. These nonresponding patients had significantly elevated lactate levels, suggesting defective aerobic metabolism. Of note, this blunted VO2 response despite maximal efforts to enhance peripheral oxygen availability predicted MOF. These data serve to re-emphasize the importance of the initial shock insult in causing or priming the host for the development of late MOF.

Adult↗
PubMed1992

Percutaneous tracheostomy/gastrostomy in brain-injured patients--a minimally invasive alternative.

Tracheostomy and gastrostomy are frequent adjunctive procedures required in the management of patients with severe brain injuries to facilitate neurorehabilitation. We therefore evaluated the use of two minimally invasive surgical procedures, percutaneous tracheostomy (PT) and percutaneous endoscopic gastrostomy (PEG), in 27 patients with severe brain injuries. The mean age was 41 +/- 4 years, and 23 (85%) were men. All patients were intubated, and 19 (70%) required mechanical ventilator support on the day of PT/PEG. The endotracheal tubes had been in place for 1 to 21 days (mean, 8.7 +/- 0.8). All patients were stable from their acute brain injury; 13 had intracranial pressure (ICP) monitors in place. The Seldinger technique, as described by Ciaglia, was employed for PT. Following PT, a PEG was inserted by a modification of the Sachs-Vine "push" technique. We were uniformly successful in placing these access tubes. Complications were minor and not clinically significant. Three of 13 patients (23%) with ICP monitors had a transient rise in ICP related to PT and one of these patients developed local subcutaneous emphysema. Another patient experienced a mild cellulitis at the tracheostomy site. Of note, there were no PEG-related complications. In conclusion, PT and PEG are readily learned, minimally invasive procedures. In our experience with patients with severe brain injuries combined PT/PEG is a uniformly safe alternative to gain long-term access to the airway and gut.

Adolescent↗
PubMed1992

Invalidation of the APACHE II scoring system for patients with acute trauma.

The APACHE II scoring system has been promulgated as a useful tool in the assessment of the severity of injury and prognosis for acutely ill patients. The physiologic basis for stratification is weighted toward older patients with chronic medical conditions. Recently, the APACHE II system has been proposed as a method for determining diagnosis related group (DRG) reimbursement for individual trauma patients. The present study applied the APACHE II scoring system to 280 patients with blunt or penetrating trauma who had documented systolic blood pressure < 90 mm Hg. Fifty-seven (20%) died of their injuries within the first 24 hours. APACHE II scores were recorded both in the emergency room (ED) and at 24 hours following admission. Injury Severity Scores (ISS), Revised Trauma Scores (RTS), and TRISSCAN were calculated. The APACHE II (n = 223) recorded at 24 hours (2.5 +/- 0.2) was significantly less than that recorded in the ED (6.6 +/- 0.3, p < 0.05, Mann-Whitney analysis). Using regression analysis, there was no correlation between APACHE II and ISS if recorded in the ED (r2 = 0.06) or 24 hours following admission (r2 = 0.08). APACHE II also demonstrated a poor correlation with the length of hospital stay (r2 = 0.03 [ED], = 0.19 [24 hours]). Whereas APACHE II may be helpful in defining severity of disease among patients with acute-on-chronic medical conditions, the classification lacks an anatomic component, which is essential to assess the magnitude of acute injury in patients who are typically otherwise healthy.

Acute Disease↗
PubMed1992

Balloon tamponade for bilobar transfixing hepatic gunshot wounds.

The nonresectional approach to major liver trauma is clearly preferred. Unfortunately, trachotomy with vessel ligation, selective hepatic arterial ligation, perihepatic pack, and fibrin glue are not viable options with high-energy bilobar liver injuries. We have fashioned a balloon tamponade device that has proved very effective for these transfixing hepatic gunshot wounds.

Adolescent↗