Search PubMedSearch

Biomedical subjects

D E Barker

Publications and source records attributed to D E Barker.

At least 19 recordsLinked to original sources

Early criteria predictive of prolonged mechanical ventilation.

This study was performed to determine if prolonged mechanical ventilation (MV) could be predicted by objective clinical variables present at 48 hours after MV was instituted. During a 3-month period, 49 (54%) of 91 mechanically ventilated surgical intensive care unit patients required MV for 2 or more days. Twelve (24%) of these patients died. Patients requiring 2-13 days of MV had significantly lower alveolar-arterial oxygen gradients (PAO2 - PAO2), PEEP, and FIO2 on MV day 2 compared with patients with MV greater than or equal to 14 days. PAO2 - PAO2 greater than or equal to 175 mm Hg on day 2 in patients without chronic obstructive pulmonary disease (COPD) was 60% sensitive and 91% specific for MV greater than or equal to 14 days. In survivors, a day-2 PAO2 - PAO2 greater than or equal to 175 mm Hg (without COPD) or a GCS score less than or equal to 9 had a 91% positive predictive value and a 96% negative predictive value for MV greater than or equal to 14 days. We conclude that mechanical ventilation for 14 or more days can be accurately predicted at 48 hours after the institution of ventilatory support by these objective criteria.

Female

The unique sequence of the herpes simplex virus 1 L component contains an additional translated open reading frame designated UL49.5.

We present evidence for the existence of an additional herpes simplex virus 1 gene designated UL49.5. The sequence, located between genes UL49 and UL50, predicts a hydrophobic protein with 91 amino acids. Attempts to delete UL49.5 were not successful. To demonstrate that UL49.5 is expressed, we made two recombinant viruses. First, we inserted in frame an oligonucleotide encoding a 15-amino-acid epitope known to react with a monoclonal antibody. This gene, consisting of the authentic promoter and chimeric coding domain, was inserted into the thymidine kinase gene of wild-type virus and in infected cells expressed a protein which reacted with the monoclonal antibody. The second recombinant virus contained a 5' UL49.5-thymidine kinase fusion gene. The protein expressed by this virus confirmed that the first methionine codon of UL49.5 served as the initiating codon. The predicted amino acid sequence of UL49.5 is consistent with the known properties of NC-7, a small capsid protein whose gene has not been previously mapped. A homolog of UL49.5 is present in the genome of varicella-zoster virus, located between homologs of UL49 and UL50.

Animals

Hip disarticulation: factors affecting outcome.

Hip disarticulation, especially in patients with peripheral vascular disease, has been associated with high morbidity and mortality rates. This report describes patient characteristics that influence the clinical outcome of hip disarticulation. The medical records of all patients undergoing hip disarticulation from 1966 to 1989 were reviewed for surgical indication, perioperative wound complications, and postoperative deaths. Fifty-three patients underwent hip disarticulation for limb ischemia (10), infection (12), infection and ischemia (14), or tumor (17). The overall incidence of wound complications was 60%, and no significant differences were found among the groups. Prior above-knee amputation and urgent/emergent operations were significantly associated with increased wound complications (p less than 0.05). The overall mortality rate was 21%, ranging from 0% (tumor) to 50% (ischemia) and differed significantly among the groups (p less than 0.02). Mortality was significantly associated with urgent/emergent operations (p less than 0.01). Age, diabetes mellitus, and previous inflow procedures did not influence mortality rates. The presence of limb ischemia influenced mortality rates to a greater extent than did infection, and a history of cardiac disease was statistically predictive of death. Wound complications frequently accompanied hip disarticulation, regardless of operative indication, and were significantly increased by urgent/emergent operations and prior above-knee amputation. Hip disarticulation can be performed with low mortality rates in selected patients. Both limb ischemia and infection substantially increase operative mortality rates.

Adult

Brachial plexus injury: association with subclavian and axillary vascular trauma.

Proximal upper extremity (subclavian and axillary) vascular injury (SAVI) and brachial plexus injury (BPI) occur uncommonly. However, BPI may be associated with SAVI and frequently is an important determinant of long-term disability. The medical records of patients with traumatic SAVI, BPI, or both over a 5-year period were reviewed. A total of 31 patients were identified. The group was predominantly male (28 men/3 women) with a mean age of 30.5 +/- 1.8 years (range, 15-63 years). Blunt trauma accounted for 43.5% of SAVI cases and 77.8% of BPI cases. Thirteen patients (41.9%) sustained SAVI alone (group I), 10 patients (32.2%) had combined SAVI and BPI (group II), and 8 patients (25.9%) had BPI alone (group III). Subclavian and axilliary vascular injury occurred in 10 of 18 patients (55.6%) with a BPI. Brachial plexus injury occurred in 10 of 23 patients (43.5%) with a SAVI. Patients with SAVI from blunt trauma were significantly more likely to have an associated complete BPI than patients with penetrating trauma. All patients with a complete BPI (6 patients) had an associated SAVI regardless of mechanism of injury. Only one patient with a partial BPI from blunt trauma had an associated SAVI. The Injury Severity Score was significantly higher for patients in group II. An average of 2.8 and 3.3 associated injuries were observed in patients with SAVI (groups I and II) versus patients without SAVI (group III), respectively. No patient who had a complete BPI showed an improvement in neurologic status during a mean follow-up of 7.2 months. No late vascular sequelae occurred in group-III patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent

Identification of three genes nonessential for growth in cell culture near the right terminus of the unique sequences of long component of herpes simplex virus 1.

We report the construction of herpes simplex virus 1 recombinants from which all or part of the coding sequences of four open reading frames have been deleted. In recombinants R7101 and R7108, the BamHI D' fragment containing the coding sequences of the dUTPase gene and the promoter-regulatory domain of a late gene was either replaced with a fragment containing a thymidine kinase gene or deleted, respectively. The recombinant R7107 lacks, in addition to BamHI D', 202 of a total of 244 predicted amino acids from the 3' end of the adjacent open reading frame UL51. The deletion in recombinant R7105 encompasses two genes, i.e., the entire open reading frame of UL47 and the amino terminus of UL46. These genes map next to that specifying the alpha trans-inducing factor. R7105, R7101, and R7108 do not exhibit demonstrable defects in viral replication. The recombinant R7107 forms minute plaques and replicates best in multiplying cells in subconfluent cultures. The results indicate that the multiplying cells supply at least some of the functions expressed by the protein encoded in UL51.

Animals

Unintentional injury death rates in rural Appalachia.

Rural unintentional injury (UI) death rates are higher than rates for urban regions. Our trauma center serves 49 rural Appalachian (AP) counties in a 120-county rural state. We investigated the impact of prehospital and hospital resources on UI death rates in our referral area. Age-adjusted and average age- and sex-specific UI death rates from 1979-1985 were compared among 49 rural AP counties, the 71 non-Appalachian (NAP) counties, and the United States. Counties were grouped for comparisons by level of prehospital care (Advanced Life Support [ALS] vs. Basic Life Support [BLS]) and by presence (H) or absence (NH) of a hospital. Death rates were calculated using data from the 1980 population census, the National Center for Health Statistics (NCHS), and state vital statistics. Within AP, all 49 counties have ambulance service. Only 9/49 (18%) have ALS service and 13/49 (26%) have no hospital. Age-specific AP rates were higher than NAP and US rates in the 25-44 and 45-64 year age groups. AP death rates were highest for BLS and NH counties across all age groups. Rural UI death rates in the region remain unacceptably high. The reason(s) that AP death rates exceed the NAP rates is uncertain. ALS service and an available hospital were associated with lower death rates. We propose both educational and epidemiologic programs to better identify and define additional problems.

Adult

Prolonged labetalol infusion for management of severe hypertension and tachycardia in a critically ill trauma patient.

A trauma victim sustained multiple injuries including cervical spine injuries, splenic laceration, and left kidney fracture. His recovery was complicated by acute renal failure, resistant hypertension, and tachycardia refractory to multiple therapies. The patient was ultimately managed with continuous infusions of labetalol 2-3 mg/min for 14 days, with adequate control of both blood pressure and heart rate. The sustained labetalol infusion was not associated with clinically significant adverse effects although a progressive decrease in heart rate was noted near the end of therapy. This downward trend in heart rate was not associated with hemodynamic compromise and returned to pretreatment baseline of 90-110 beats/min upon discontinuation of parenteral therapy and initiation of oral labetalol. The prolonged use of labetalol infusions may be beneficial in certain patients. Further work needs to be done to identify the safety and efficacy of labetalol infusions.

Adult

Monokine depression of bile flow in the isolated perfused rat liver.

Multiple system organ failure (MSOF) is a progressive dysfunction of vital organs that may develop in clinical settings such as sepsis or multiple trauma. One component of this syndrome is cholestasis and impaired liver function. The mechanism(s) for this liver failure (and the failure of other organs) remains obscure. Macrophages and Kupffer cells have been shown to secrete cytokines such as interleukin-1 and tumor necrosis factor. These cytokines mediate many aspects of the acute phase response, and they also can produce cellular injury. The purpose of this study was to evaluate the effects of a semipurified murine monokine preparation having interleukin-1 activity on bile flow in the rat isolated perfused liver (IPL). The monokine preparation produced a significant reduction of bile flow in the IPL system. The effect could not be explained by a venoocclusive phenomenon or residual endotoxin in the monokine preparation. We conclude that a semipurified monokine preparation having interleukin-1 but not tumor necrosis activity produced a significant depression of bile flow in the IPL, and we suggest that macrophage secretory product(s) may be responsible for the cholestasis in MSOF.

Animals

Gastrointestinal disconnection and the treatment of intra-abdominal sepsis.

Current operative treatment for intra-abdominal sepsis secondary to internal gastrointestinal fistulas is aimed at wide drainage of septic foci and elimination of continued peritoneal soilage. Although methods for surgical drainage of abscesses and fistulous tracts are well established, the optimal method for surgical prevention of continued peritoneal soilage remains controversial. The authors applied the principle of complete gastrointestinal disconnection and performed diversion of the gastrointestinal tract and tube decompression proximal to the fistulous opening in the treatment of 22 critically ill patients with intra-abdominal sepsis from gastric or small bowel fistulas. Patient survival varied according to the level of the site of gastrointestinal leakage. All patients (5 out of 5) who had leakage in the distal small bowel survived. Six of nine (66%) patients with leakage from the proximal jejunum and six of eight (75%) of patients with gastroduodenal leakage survived. The overall survival rate of 77 per cent observed in this group of patients supports the authors' hypothesis that complete gastrointestinal disconnection is a valuable adjunct in the treatment of these severely ill patients.

Abdomen

Resistance of rapidly expanded random skin flaps to bacterial invasion.

This study tested the hypothesis that rapidly expanded random pattern skin flaps demonstrate enhanced resistance to bacterial invasion from intradermal injection of Staphylococcus aureus in a porcine model. Sites for a 6 X 12 cm expanded, a 6 X 9 cm sham-expanded, and a 6 X 6 cm acute random pattern skin flap were outlined, but not elevated, on the backs of 14 white pigs. A 450-cc tissue expander inserted beneath the panniculus carnosus at the site for expansion was sequentially filled to the limits of skin viability each day for 5 days. At the sham site a tissue expander was similarly inserted but left unexpanded; the acute flap site was left undisturbed. On day 8, flaps were elevated, immediately sutured in place, and 0.1 ml of saline solution containing 10(7) Staphylococcus aureus inoculated intradermally at four corresponding sites in each flap and at three sites in normal skin. In seven animals these sites were at the proximal base of the flaps; in seven others the sites were distal. The resulting areas of erythema and skin ulceration were measured on each of the next 3 days and the measurements compared. At corresponding proximal sites, the mean area of erythema and ulceration measured over the next 3 days in expanded flaps (31.2 mm2) and in sham-expanded flaps (33.8 mm2) was significantly less than in acute flaps and control skin (47.5 mm2, 43.4 mm2, p less than 0.05). Measurements in the rapidly expanded flaps were not significantly different than those in the sham-operated expanded flaps.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals

New low-bleed implant--Silastic II.

A new low-bleed breast implant has been tested both clinically and experimentally. In the guinea pig, two-thirds of the capsules are thin; there is less inflammation and less foreign body reaction than we have seen in previous implants. Evaluations by various investigators show good patient and surgeon acceptance of the new low-bleed implants.

Animals

Cause for alarm.

Explore the source record for details and available documents.

Dental Offices

"Bleeding" of silicone from bag-gel breast implants, and its clinical relation to fibrous capsule reaction.

We present evidence of the following. 1. Modern silicone bag-gel breast implants leak silicone gel through the bag. 2. The amount of silicone leaked by an intact implant varies from one implant to another, and is not constant for any type or brand. 3. The leaked silicone, together with fibrous thickening and various degrees of inflammation will be found in capsules surrounding the implants if extensive biopsies are taken and many sections are examined.

Biopsy