Biomedical subjects

David W Tuggle

Publications and source records attributed to David W Tuggle.

8 recordsLinked to original sources

PubMed2005

Pediatric major resuscitation--respiratory compromise as a criterion for mandatory surgeon presence.

UNLABELLED: The American College of Surgeons Committee on Trauma has indicated that there are minimum criteria for a trauma surgeon to respond to a major resuscitation (MR) within 15 minutes. These criteria have been required for children without significant data to support their validity. Our hypothesis is that prehospital intubation/respiratory compromise (IRC) as a criterion to define an MR will be an accurate predictor. METHODS: The trauma registry of a level I trauma center was used for data collection of age, injury severity score (ISS), IRC, mortality, hospital days, intensive care unit (ICU) days, and emergency operations. Chi2 with Yates correction and Mann-Whitney rank-sum testing was used for statistical analysis expressed as mean +/- SEM. RESULTS: One hundred eighteen patients were encoded as MR. Forty patients had prehospital IRC and 78 patients did not. There were statistically significant differences seen in ISS, ICU length of stay, and mortality (P < .001). Forty-five percent of patients with IRC died. None of the patients without IRC died. CONCLUSION: Injured children with prehospital IRC are significantly more likely to die, have a higher ISS, and a longer ICU length of stay. Prehospital respiratory distress in injured children in our trauma system is a reasonable criterion to define an MR in children.

Child↗

PubMed2004

Using a bioabsorbable copolymer plate for chest wall reconstruction.

Reconstruction of the chest wall in a child is an uncommon problem for pediatric surgeons. The available material for chest wall reconstruction typically has been borrowed from the adult experience. The authors describe their recent experience with a commercially available bioabsorbable plate in a variety of conditions that require chest wall reconstruction.

Absorbable Implants↗

PubMed2004

Surgeon-directed ultrasound for trauma is a predictor of intra-abdominal injury in children.

This study investigated the efficacy of surgeon-directed focused assessment with sonography for trauma (FAST) in conjunction with physical exam (PEx) as a predictor of intra-abdominal injury in children. Injured children (ages < or = 17) presenting to a level I trauma center with abdominal trauma were evaluated in the emergency department (ED) by the trauma team of surgical attendings and residents. PEx and FAST were performed immediately upon arrival to the ED and results compared to CT, the standard exam for presence of intra-abdominal injury. Data was collected prospectively from July 1, 2000, until April 30, 2002. One hundred and twenty injured children underwent evaluation of abdominal trauma with PEx, FAST, and abdominal CT. Two patients had false-negative CT scans. Bayesian analysis was applied to the results of the remaining 118 patients. FAST compared with CT findings revealed sensitivity 70 per cent, specificity 100 per cent, positive predictive value 100 per cent, and negative predictive value 92 per cent. FAST results were combined with PEx findings such that either suggestive of intra-abdominal injury was regarded as a "positive exam." Sensitivity was 100 per cent, specificity 74 per cent, positive predictive value 53 per cent, and negative predictive value 100 per cent. Surgeon-directed FAST with consideration of PEx is a predictor of intra-abdominal injury in children.

Abdominal Injuries↗

PubMed2003

Selected-area growth of carbon nanotubes by the combination of focused ion beam and chemical vapor deposition techniques.

In this article, we report a technique for growing carbon nanotubes in a more controllable fashion, which enables us to synthesize nanotubes directly in various forms of designed patterns. This nanofabrication process is based on a combination of focused ion beam (FIB) and chemical vapor deposition (CVD) techniques. In this process, arrays of conductive patterns were first deposited on silicon substrates by directing a gaseous compound (C(9)H(16)Pt) via the capillary needle-sized nozzles within a FIB system. The substrates were then coated with catalyst and further modified by the FIB to localize the position of the catalyst. Finally, the growth of carbon nanotubes on the designed substrates was carried out by CVD of hydrocarbon gases. This fabrication technique has the advantage of positioning carbon nanotubes in selected locations. This may open up opportunities for the direct synthesis of carbon nanotubes onto almost any substrate material, thus allowing fabrication of carbon nanotube-based devices.

Gases↗

PubMed2003

The impact of intra-abdominal hypertension on gene expression in the kidney.

BACKGROUND: Intra-abdominal hypertension (IAH) has been recognized as a source of morbidity and mortality in the injured patient. Research concerning this entity has focused predominantly on the pathophysiology. We developed a model of IAH to determine whether gene expression is altered in the presence of this condition. METHODS: Using general anesthesia, adult Sprague-Dawley rats were intubated and instrumented with a carotid and jugular catheter. Three pairs of rats (three control; three IAH 25 mm Hg) were used at each time interval. Continuous measurements of heart rate, blood pressure, cardiac output, and temperature were recorded. Arterial blood gases were measured every 30 minutes. A catheter was placed in the peritoneum and warm saline was infused up to a pressure of 25 mm Hg that was measured through this catheter continuously. At 30 and 60 minutes, the kidneys were harvested and standard protocols were used to extract nucleic acid and perform cDNA microarray analysis screening for 4,000 genes. Each experimental rat was paired with a control rat and each set underwent individual cDNA array analysis. RESULTS: Hemodynamic changes occurred that were consistent with IAH, including depression of cardiac output and acidosis. Although widespread changes in gene expression were identified, only genes that were up-regulated and down-regulated by a ratio of fivefold, a difference in magnitude of 150 molecular dynamic counts, and p < 0.05 were considered significant. When comparing IAH of 25 mm Hg at 30 and 60 minutes, there was a surprising decrease in up-regulated genes from 10 to 1. In addition, there was an increase in down-regulated genes from zero to five genes. CONCLUSION: IAH causes changes in gene up- and down-regulation in the kidney. The number and types of genes change in magnitude and type over time. Further investigation into renal gene expression may offer insight into the molecular pathophysiology of IAH.

Animals↗

PubMed2003

Blast injury.

Individuals with a blast injury are the victims most likely to be seen by any healthcare professional. An awareness of the potential injuries is important. Individual care should follow standards established for all trauma patients.

Blast Injuries↗

PubMed2002

Pediatric vacuum packing wound closure for damage-control laparotomy.

BACKGROUND/PURPOSE: Recent studies advocate the use of the open-abdomen technique for managing the abdominal compartment syndrome and uncontrolled intraperitoneal sepsis. The authors have used vacuum packing (Vac-Pac) in pediatric patients with excellent results and have developed a method for closing widely distracted fascial edges to avoid the need for skin grafting. METHODS: Patients who had an intraabdominal catastrophe best managed by a temporary open-abdomen technique were included. After damage control laparotomy, the Vac-Pac temporary closure was used. In 2 patients a corsetlike lacing was used to bring the widely separated fascial edges together gradually. RESULTS: Five patients with intraabdominal sepsis and one with the abdominal compartment syndrome were included. The length of time the Vac-Pac was used ranged from 3 to 21 days. In 2 patients, the corset closure allowed wound approximation within 5 to 7 days. One patient died of overwhelming sepsis, the remainder of the patients survived. CONCLUSIONS: The Vac-Pac technique for abdominal closure is a simple and inexpensive means by which to manage the open abdomen in the pediatric patient effectively. Use of a corset-type closure for wounds with widely distracted edges should eliminate the need for skin grafting over an open abdomen.

Abdomen↗

PubMed2002

Effects of hydrogen on the formation of aligned carbon nanotubes by chemical vapor deposition.

Well-aligned carbon nanotubes with controllable properties were grown on porous silicon substrates by thermal chemical vapor deposition. The morphologies of the carbon nanotubes were varied with the introduction of H2 during the catalyst activation and/or carbon nanotube growth processes. It was found that H2 promotes the growth of carbon nanotubes while preventing the formation of spherical amorphous carbon particles. Without the introduction of H2 during the C2H2 thermal decomposition, aligned carbon nanotubes mixed with spherical carbon particles were formed on the substrate. However, with the introduction of H2, pure carbon nanotubes were synthesized. These nanotubes also had uniform diameters of 10-20 nm, which is much smaller than nanotubes synthesized without H2. The average growth rate of nanotubes was also affected by the introduction of hydrogen into the reaction chamber during nanotube growth. With the addition of hydrogen, the average growth rate changed from 78 nm/s to 145 nm/s. A possible growth mechanism, including the effect of a high ratio of H2 to C2H2, is suggested for the growth of these well-aligned carbon nanotubes with uniform diameters.

Carbon↗