Characterization of the nasal, sublingual, and oropharyngeal mucosa microbiota in cleft lip and palate individuals before and after surgical repair.

OBJECTIVE: To delineate inherent differences in the microbial milieu in cleft palate patients compared with cleft lip patients and to document changes in microbial flora before and after cleft lip and palate repair. DESIGN: A prospective study of preoperative and postoperative culture results from the nasal, sublingual, and oropharyngeal surfaces of patients undergoing primary cleft lip repair and palate closure. SETTING: Shriners Hospitals for Children, Galveston, Texas, and University of Texas Medical Branch, Galveston, Texas. PATIENTS: Seventy-nine patients were included in a 3-year period. Ten patients with isolated cleft lip underwent primary lip repair. Twenty-five patients with cleft lip and palate underwent primary lip repair, and 44 patients underwent palatoplasty. RESULTS: Cleft palate patients had a significantly higher rate of colonization by staphylococcal species, but not methicillin-resistant Staphylococcus aureus , when compared to cleft lip patients (p=.0298; chi-square test). Closure of the palatal cleft coincided with significant decline in the prevalence of Klebsiella and Enterobacter species (p<.05; McNemar test). The only major complication, palatal dehiscence, was believed to be directly related to infection with group A beta-hemolytic streptococci. CONCLUSIONS: Despite a high prevalence of potential pathogenic and enteric flora preoperatively in primary palate repair, postoperative wound infection is rare in the prospective study population. However, the presence of beta-hemolytic streptococci was associated with a higher risk of repair dehiscence; therefore, screening for Streptococci prior to surgery should be performed routinely.

Topical Sulfamylon cream inhibits DNA and protein synthesis in the skin donor site wound.

BACKGROUND: Whereas Sulfamylon is effective in treatment of burn wound infection, controversy exists regarding its effect on the healing process. METHODS: A partial thickness skin donor site wound was created on the back and indwelling catheters were placed in the carotid artery and jugular vein in rabbits under general anesthesia. Sulfamylon cream (8.5%, BERTEK Pharmaceuticals Inc., Morgantown, W Va) was applied on the wound, with either open or occlusive dressing. The control wound was covered with dressings only. On day 7 after injury, stable isotope tracers were infused to determine the fractional synthetic rate (FSR) of DNA, and FSR and fractional breakdown rate (FBR) of protein in the wound. RESULTS: In the Sulfamylon-open dressing group, the DNA FSR was 1.3 +/- 0.6%/day, the protein FSR was 8.0 +/- 3.5%/day, and the net protein deposition (FSR - FBR) was -0.3 +/- 3.7%/day. These values were lower (P < .01 to .05) than the corresponding values in the control group (DNA FSR: 2.9 +/- 0.9%/day; protein FSR: 20.5 +/- 8.4%/day; net protein deposition: 7.9 +/- 6.0%/day). Sulfamylon cream selectively inhibited DNA FSR from the de novo base synthesis pathway (2.3 +/- 1.2 vs 0.8 +/- 0.5%/day, P < .05 vs control). With the occlusive dressing Sulfamylon cream did not decrease wound DNA FSR due to a stimulation of the base salvage pathway, but still decreased protein FSR (11.5 +/- 5.1%/day, P < .05 vs control). Histologic slides indicated that Sulfamylon cream inhibited re-epithelialization, collagen formation, and angiogenesis in the wound. CONCLUSIONS: Topical Sulfamylon cream application inhibited DNA and protein synthesis in the wound, which would be expected to retard the healing process.

Gentamicin improves hemodynamics in ovine septic shock after smoke inhalation injury.

Previously, our group developed an ovine model of hyperdynamic sepsis associated with acute lung injury. In this study, we sought to modify this sepsis model by the administration of gentamicin to more closely simulate the symptoms observed in human sepsis in the intensive care unit. In a prospective, controlled, randomized laboratory experiment, 18 female sheep were surgically prepared for chronic study. After a tracheotomy had been performed, the sheep were randomized into sham, control, and gentamicin groups (n = 6 each). Sham animals were surgically prepared for the study but were neither injured nor treated. Control and gentamicin animals received 48 breaths of cotton smoke (<40 degrees C) followed by the instillation (via a bronchoscope) of live Pseudomonas aeruginosa (2-5 x 10(11) colony-forming units) bacteria into the lung. All sheep were mechanically ventilated with 100% O2 for the duration of the 24-h experimental period. Gentamicin (2 mg/kg) was administered at 6, 12, and 18 h after injury. The animals were resuscitated with lactated Ringer's solution to maintain filling pressures and hematocrit on a constant level. Cardiopulmonary variables were stable in sham animals, but in the control group, cardiac index increased significantly after 24 h versus baseline (BL, 5.1 +/- 0.4 L.min(-1).m(-2) vs. 24 h, 7.3 +/- 0.7 L.min(-1).m(-2); P < 0.05); this was associated with a significant drop in mean arterial pressure (BL, 95 +/- 3 mmHg vs. 24 h, 65 +/- 4 mmHg, P < 0.05) and systemic vascular resistance index (BL, 1410 +/- 118 dynes s.cm.m vs. 24 h, 598 +/- 101 dynes s.cm.m, P < 0.05). Treatment with gentamicin stabilized cardiac index (BL, 5.0 +/- 0.4 L.min(-1).m(-2) vs. 24 h, 4.7 +/- 0.4 L.min(-1).m(-2)) and attenuated the decrease in mean arterial pressure (BL, 99 +/- 3 mmHg vs. 24 h, 84 +/- 4 mmHg) and systemic vascular resistance index (BL, 1573 +/- 173 dynes s.cm.m vs. 24 h, 1263 +/- 187 dynes s.cm.m). In addition, the fluid requirement in the gentamicin group was significantly lower than in the control group. Pulmonary function remained stable in sham animals, but the PaO2/FiO2 ratio and shunt fraction deteriorated similarly in the control and the gentamicin groups. Because gentamicin improved hemodynamic variables and reduced the fluid requirement in this ovine model, we believe that this modified sepsis model might provide a clinically relevant and useful new approach for future studies focusing on hemodynamic variables and outcome.

Assessing and controlling wound infection.

Quantitatively, wounds harboring bacteria that exceed 105 colony-forming units per gram are considered infected wounds. There are acute wounds and chronic wounds, and the approach to controlling the infection is similar. Although the granulating bed may be avascular, systemic anti-infectives are employed adjunctively to circumvent systemic infection. The main armamentarium of the attack is the use of topical anti-infectives, which invade the bacteria where they reside, and, consequently, reduce their numbers and promote wound healing.

The effectiveness of processed grapefruit-seed extract as an antibacterial agent: I. An in vitro agar assay.

OBJECTIVES: Grapefruit-seed extract (GSE) Citricidal has, in recent reports, been reported to be successful in combating a variety of common infectious agents. In our study, drops of concentrated grapefruit-seed extract were tested for antibacterial properties against a number of gram-positive and gram-negative organisms. DESIGN: Sixty-seven (67) distinct biotypes were tested for their susceptibilities to the GSE as well as to 5 other topical antibacterials (Silvadene, Sulfamylon, Bactroban, Nitrofurazone, and Silvadene, Nystatin). Wells were punched into Mueller-Hinton agar plates, which were then inoculated with the organism to be tested; each well was then inoculated with one of the antibacterial agents. After an overnight incubation period, the plates were checked for zones of bacterial susceptibility around the individual wells, with a measured susceptibility zone diameter of 10 mm or more considered a positive result. RESULTS: The GSE was consistently antibacterial against all of the biotypes tested, with susceptibility zone diameters equal to or greater than 15 mm in each case. CONCLUSIONS: Our preliminary data thus suggest an antibacterial characteristic to GSE that is comparable to that of proven topical antibacterials. Although the GSE appeared to have a somewhat greater inhibitory effect on gram-positive organisms than on gram-negative organisms, its comparative effectiveness against a wide range of bacterial biotypes is significant.

Comparison of propolis skin cream to silver sulfadiazine: a naturopathic alternative to antibiotics in treatment of minor burns.

BACKGROUND: Propolis, a naturopathic substance derived from bees wax extract, has recently been praised for its antimicrobial, anti-inflammatory, and cicatrization-enhancing properties. OBJECTIVE: In our study, we compare these properties in a high-grade Brazilian propolis skin cream directly with silver sulfadiazene (SSD) in the treatment of minor burns (superficial second degree) in the ambulatory care setting (less than 20% total body surface area burned). SETTINGS/LOCATION: The study was conducted at the burn clinic in Pronto Socorro para Queimaduras, Gioania, Brazil. SUBJECT: Patients were admitted to the study only if their initial presentation for burn care was within 48 hours postinjury and if bilateral wounds of similar depth and quality were present. INTERVENTIONS: Patients had propolis skin cream applied to one wound and SSD applied to the other selected wound on initial presentation and underwent debridement and dressings change the following morning. Patients subsequently returned to the clinic every 3 days to have the wounds checked and dressings changed. At these check-ups, wounds were cultured for microbial growth and photographed to document inflammation and cicatrization. Patients were instructed not to disturb their wounds or change their dressings at home, thus propolis skin cream and SSD were applied to the wounds only at the specified 3-day intervals. RESULTS: Our preliminary results do not show any significant difference in microbial colonization between wounds treated with SSD and propolis skin cream, however, wounds treated with propolis skin cream consistently showed less inflammation and more rapid cicatrization then those treated with SSD. CONCLUSION: Propolis skin cream appears to have a beneficial effects on the healing of partial thickness burn wounds. If dressings had been changed more frequent the antimicrobial and wound healing effects would have been enhanced.

The effectiveness of processed grapefruit-seed extract as an antibacterial agent: II. Mechanism of action and in vitro toxicity.

OBJECTIVES: Recent testimonials report grapefruit-seed extract, or GSE (Citricidal) to be effective against more than 800 bacterial and viral strains, 100 strains of fungus, and a large number of single and multicelled parasites. This study investigated GSE for antibacterial activity at varying time intervals and concentration levels and tissue toxicity at varying concentrations in an effort to determine if a concentration existed that was both microbicidal and nontoxic and in what period of time. DESIGN: Gram-negative and gram-positive isolates were introduced into graduated dilutions of GSE (twofold concentrations ranging from 1:1, through 1:512) for determination of bacterial activity. In vitro assays with human skin fibroblast cells were also performed at the same dilutions to determine toxicity. RESULTS: These tests indicated that from the 1:1 through the 1:128 concentrations, GSE remained toxic as well as bactericidal. However, test results indicated that at the 1:512 dilution, GSE remained bactericidal, but completely nontoxic. CONCLUSIONS: The initial data shows GSE to have antimicrobial properties against a wide range of gram-negative and gram-positive organisms at dilutions found to be safe. With the aid of scanning transmission electron microscopy (STEM), the mechanism of GSE's antibacterial activity was revealed. It was evident that GSE disrupts the bacterial membrane and liberates the cytoplasmic contents within 15 minutes after contact even at more dilute concentrations.

Correlation of bronchoalveolar lavage with radiographic evidence of pneumonia in thermally injured children.

The diagnosis of pneumonia in the critically ill patient is very difficult because the usual signs and symptoms are unreliable in the intensive care setting. Bronchoalveolar lavage (BAL) is a diagnostic tool with a reported sensitivity of 70%. The purpose of this study was to determine the efficacy and specificity of BAL in severely burned pediatric patients. An analysis was performed in which BAL cultures were compared and correlated to chest radiographs. Patient characteristics, such as age, sex, burn size, depth of burn, and the presence of inhalation injury were evaluated. Over a period of 18 months, 58 thermally injured children were identified who underwent 101 BALs. The mean age was 6.5 +/- 5 years, mean TBSA was 39 +/- 27%, and inhalation injury was diagnosed in 20 patients (35%). Of 101 BALs, 48 were positive, and of the 101 chest radiographs, 20 demonstrated signs of pneumonia. Ten of those were associated with a positive BAL and 10 with a negative BAL. Thus, the positive predictive value of BAL was 21%, whereas the negative predictive value was 81%. Interestingly 80% of patients with tracheobronchitis from inhalation injury demonstrated a positive BAL. We conclude that in pediatric burn patients BAL correlates poorly with radiographic signs of pneumonia.

Empiric antibiotic therapy for seawater injuries: a four-seasonal analysis.

BACKGROUND: Previous seawater studies found Vibrio species associated with morbidity, suggesting that seawater-contaminated wounds should be treated early. The purpose of this study was to identify common seawater pathogens and antibiotic sensitivities to provide empiric antibiotic therapy until patient-specific culture results are available. METHODS: Seasonal samples were collected from 25 Galveston beach locations and cultured. Colonies were identified and sensitivities were performed using MicroScan Positive and Negative Breakpoint Combo Panels. RESULTS: In the fall (28.3 degrees C), of 15 species isolated, the three most common isolates were Escherichia coli, Enterococcus faecium, and Klebsiella pneumoniae. Gram-negative isolates were sensitive to levofloxacin, lomefloxacin, and cefepime. Gram-positive isolates were sensitive to penicillin and ampicillin. In the winter (11.1 degrees C), of 14 species isolated, the three most common isolates were Enterobacter agglomerans, E. faecium, and E. coli. Gram-negative isolates were sensitive to levofloxacin, lomefloxacin, and cefepime. Most Gram-positive isolates were sensitive to vancomycin, levofloxacin, penicillin, and ampicillin. In the spring (26.6 degrees C), of 14 species isolated, the three most common isolates were E. coli, Bacillus species, and E. faecium. Gram-negative isolates were sensitive to levofloxacin, lomefloxacin, and cefepime. Most Gram-positive isolates were sensitive to penicillin, ampicillin, vancomycin, and levofloxacin. In the summer (29.7 degrees C), of 17 bacterial species isolated, the three most common isolates were Bacillus species, Enterobacter cloacae, and K. pneumoniae. Gram-negative isolates were sensitive to cefepime, lomefloxacin, and levofloxacin. Gram-positive isolates were sensitive to penicillin, ampicillin, vancomycin, levofloxacin, and chloramphenicol. CONCLUSIONS: Cultured pathogens were sensitive to penicillin, ampicillin, or levofloxacin. The authors recommend a combination of penicillin or ampicillin with levofloxacin for empiric antibiotic coverage for seawater-contaminated injuries.

The potential benefit of 5% Sulfamylon Solution in the treatment of Acinetobacter baumannii-contaminated traumatic war wounds.

BACKGROUND: The recent report of high numbers of Acinetobacter baumannii bloodstream infections among service members injured in Iraq and Afghanistan during the period January 2002 through August 2004 has prompted an investigation into their etiology. A review of the current guidelines for open combat casualty wounds as part of this broad investigation was not mentioned in the report. OBJECTIVE: The objective of this study was 2-fold: to ascertain the susceptibility of A. baumannii to currently available topical antibacterial agents and (2) to propose an alternative, effective treatment protocol for contaminated combat-related wounds so as to reduce or eliminate the likelihood of the wound serving as the source of A. baumannii infection or septicemia. METHODS: A standardized antimicrobial susceptibility study of 43 strains of A. baumannii collected from a tertiary care burn center was conducted using 2 commonly used topical antibacterial agents, 1% silver sulfadiazine cream (Silvadene) and 5% mafenide acetate solution (5% Sulfamylon Solution). RESULTS: Both were effective, but 5% Sulfamylon Solution demonstrated significantly greater antibacterial activity. CONCLUSION: Five percent Sulfamylon Solution, initially developed for wartime use, and currently limited by the Food and Drug Administration to soaks following meshed split-thickness autografts following excision of second-degree and third-degree burns, has a broad spectrum of antibacterial activity and extensive off-label applicability. It is an ideal agent for use in the treatment of war wounds, and should be considered as a superior replacement for normal saline in the current guidelines for open combat casualty wounds.

Comparison of in vitro disc diffusion and time kill-kinetic assays for the evaluation of antimicrobial wound dressing efficacy.

There is a plethora of new silver-containing dressings on the market today. Various manufacturers attempt to show that their dressings are the most efficacious and therefore should be preferentially employed by health care workers based on the results of their in vitro tests. However, there have been no studies that clearly identify which tests are appropriate for comparison purposes. The purpose of this study was to determine which in vitro test is most appropriate for evaluating the antimicrobial efficacy of silver-containing dressings. This was done by testing seven silver-containing dressings and two non-silver-containing topical agents against 17 clinically relevant microorganisms using zone of inhibition assays and time-kill kinetic assays in complex media. The results for the two assays were then correlated to determine whether the methods generated similar results. It was determined that the two methods do not correlate at all. This is most likely a result of the silver interacting with the media in the zone of inhibition test, thus invalidating the results of this test. We therefore conclude that zone of inhibition data generated for silver-containing dressings is of little value when assessing antimicrobial efficacy and that time-kill assays are of greater use.

Effects of interleukin-1alpha administration on intestinal ischemia and reperfusion injury, mucosal permeability, and bacterial translocation in burn and sepsis.

OBJECTIVE: To evaluate the effect of interleukin-1alpha (IL-1alpha) on the mesenteric circulation, intestinal mucosal integrity, and bacterial translocation in a burn/endotoxemia chronic porcine model. SUMMARY BACKGROUND DATA: Major burn and sepsis are associated with a high mortality, ischemia/reperfusion injury to the intestine, and an increased rate of bacterial translocation. Pathologic alterations of IL-1 synthesis, degradation, and binding to receptors have been reported. Manipulation of IL-1-mediated effects might be of therapeutic utility. METHODS: Twenty-one female pigs were instrumented with an ultrasonic flow probe on the superior mesenteric artery and a catheter into the superior mesenteric vein. After 5 days, all animals were anesthetized, and 14 received 40% total body surface area third-degree burn. IL-1alpha was administered intravenously at 1,000 ng/kg to seven pigs immediately after burn. Eighteen hours after burn, 100 microg/kg lipopolysaccharide (LPS) was administered intravenously. Systemic and splanchnic hemodynamics were measured and blood samples were drawn for blood gas analysis. Intestinal permeability was assessed every 6 hours by measuring the lactulose/mannitol (L/M) excretion ratio. At the end of the study (42 hours), tissue samples were harvested for bacteriologic cultures. RESULTS: Mesenteric blood flow was significantly decreased after burn and endotoxin. Administration of IL-1alpha significantly improved mesenteric blood flow postburn and post-LPS. Mesenteric oxygen supply and consumption showed a significant reduction after burn. In contrast, animals treated with IL-1alpha showed an increase in postburn mesenteric oxygen supply and consumption. LPS-induced mesenteric hypoxia was also ameliorated by IL-1alpha treatment. Intestinal permeability, as assessed by the L/M ratio, showed a 7- and 10-fold elevation after thermal injury and LPS, respectively. In contrast, IL-1alpha-treated animals showed an increase of only three- and fourfold in the L/M ratio, respectively. Bacterial translocation was significantly increased in the burn/endotoxin group. IL-1alpha significantly reduced the rates of bacterial translocation. CONCLUSIONS: IL-1alpha treatment attenuates mesenteric ischemia and reperfusion injury induced by thermal injury and endotoxemia by improving mesenteric blood flow and oxygenation. Subsequently, IL-1alpha reduces intestinal permeability and bacterial translocation after burn and sepsis.

Effects of early excision and aggressive enteral feeding on hypermetabolism, catabolism, and sepsis after severe burn.

BACKGROUND: Severe burn induces a systemic hypermetabolic response, which includes increased energy expenditure, protein catabolism, and diminished immunity. We hypothesized that early burn excision and aggressive enteral feeding diminish hypermetabolism. METHODS: Forty-six burned children were enrolled into a cohort analytic study. Cohorts were segregated according to time from burn to transfer to our institution for excision, grafting, and nutritional support. No subject had undergone wound excision or continuous nutritional support before transfer. Resting energy expenditure, skeletal muscle protein kinetics, the degree of bacterial colonization from quantitative cultures, and the incidence of burn sepsis were measured as outcome variables. RESULTS: Early, aggressive treatment did not decrease energy expenditure; however, it did markedly attenuate muscle protein catabolism when compared with delay in aggressive treatment. Wound colonization and sepsis were diminished in the early treatment group as well. CONCLUSION: Early excision and concurrent aggressive feeding attenuate muscle catabolism and improve infectious outcomes after burn.