Bacterial reduction and shift with NPWT after surgical debridements: a retrospective cohort study.

BACKGROUND: Surgical debridement, negative-pressure wound therapy (NPWT) and antibiotics are used for the treatment of open wounds. However, it remains unclear whether this treatment regimen is successful in the reduction and shift of the bacterial load. METHODS: After debridement in the operating room, NPWT, and antibiotic treatment, primary and secondary consecutive microbiological samples of 115 patients with 120 open wounds with bacterial or yeast growth in ≥1 swab or tissue microbiological sample(s) were compared for bacterial growth, Gram staining and oxygen use at a level one trauma center in 2011. RESULTS: Secondary samples had significantly less bacterial growth (32 vs. 89%, p < .001, OR 17), Gram-positive bacteria (56 vs. 78%, p = .013), facultative anaerobic bacteria (64 vs. 85%, p = .011) and Staphylococcus aureus (10 vs. 46%, p = .002). They also tended to include relatively more Coagulase-negative Staphylococci (CoNS) (44 vs. 18%) and Pseudomonas species (spp.) (31 vs. 7%). Most (98%) wounds were successfully closed within 11 days, while wound revision was needed in 4%. CONCLUSIONS: The treatment regimen of combined use of repetitive debridement, irrigation and NPWT in an operating room with antibiotics significantly reduced the bacterial load and led to a shift away from Gram-positive bacteria, facultative anaerobic bacteria, and S. aureus, as well as questionably toward CoNS and Pseudomonas spp. in this patient cohort. High rates of wound closure were achieved in a relatively short time with low revision rates. Whether each modality played a role for these findings remains unknown.

High risk of adverse events in hospitalised hip fracture patients of 65 years and older: results of a retrospective record review study.

OBJECTIVES: Hip fracture patients of 65 years and older are a complex patient group who often suffer from complications and difficult rehabilitation with disappointing results. It is unknown to what extent suboptimal hospital care contributes to these poor outcomes. This study reports on the scale, preventability, causes and prevention strategies of adverse events in patients, aged 65 years and older, admitted to the hospital with a primary diagnosis of hip fracture. DESIGN, SETTING AND OUTCOME MEASURES: A retrospective record review study was conducted of 616 hip fracture patients (≥65 years) admitted to surgical or orthopaedic departments in four Dutch hospitals in 2007. Experienced physician reviewers determined the presence and preventability of adverse events, causes and prevention strategies using a structured review form. The main outcome measures were frequency of adverse events and preventable adverse events in hospitalised hip fracture patients of 65 years and older, and strategies to prevent them in the future. RESULTS: 114 (19%) of the 616 patients in the study experienced one or more adverse events; 49 of these were preventable. The majority of the adverse events (70%) was related to the surgical procedure and many resulted in an intervention or additional treatment (67%). Human causes contributed to 53% of the adverse events, followed by patient-related factors (39%). Training and close monitoring of quality of care and the health professional's performance were the most often selected strategies to prevent these adverse events in the future. CONCLUSIONS: The high percentage of preventable adverse events found in this study shows that care for older hospitalised hip fracture patients should be improved. More training and quality assurance is required to provide safer care and to reduce the number of preventable adverse events in this vulnerable patient group.

Risk factors for prolonged treatment and hospital readmission in 280 cases of negative-pressure wound therapy.

BACKGROUND: There is evidence of certain beneficial effects and increasing understanding of the mechanisms of action of negative-pressure wound therapy (NPWT). However, it is known that prolonged duration of NPWT is associated with increased bacterial growth and efforts should be made to decrease the duration of NPWT. It was the aim of this study to evaluate potential risk factors for the duration, from first application of NPWT to secondary wound closure and to identify factors that increase the rate of hospital readmission. METHODS: In a retrospective cohort study, 261 patients (46 ± 19 years, 70 female) who underwent 280 treatments with NPWT were analysed. Patient-specific and demographic characteristics and the presence of several risk factors were documented. The duration of treatment from first application of NPWT to secondary wound closure, the number of interventions, the duration of hospital stay and the incidence of readmissions due to complications of the wound treated by NPWT were recorded and a risk factor analysis was performed. RESULTS: The median number of NPWT procedures was 2.0 ± 2.0, the duration of NPWT was 6.0 ± 14.7 days and the length of hospital stay was 16.0 ± 27.9 days. Presence of an open fracture (p = .002) and increased age (p = .004) were identified as independent risk factors for a prolonged duration of NPWT. Patients who smoked (p = .001) or patients with alcohol/drug abuse (p = .015) were more likely to return to hospital (smoking: 18 out of 58 cases; alcohol/drug abuse: 7 out of 19 cases). No such association was seen for diabetes (p = .702), peripheral vascular disease (PVD) (p = .052), immunosuppressive medication (p = .187), immunodeficiency (p = .404), trauma (p = .358), infection (p = .298) and open fracture (p = .061). CONCLUSIONS: Patient age and presence of an open fracture are independent predictors of a prolonged duration from first application of NPWT to secondary wound closure. These results should be taken into account for the calculation of average costs and anticipated hospital stay associated with this therapy.

Maggot excretions inhibit biofilm formation on biomaterials.

BACKGROUND: Biofilm-associated infections in trauma surgery are difficult to treat with conventional therapies. Therefore, it is important to develop new treatment modalities. Maggots in captured bags, which are permeable for larval excretions/secretions, aid in healing severe, infected wounds, suspect for biofilm formation. Therefore we presumed maggot excretions/secretions would reduce biofilm formation. QUESTIONS/PURPOSES: We studied biofilm formation of Staphylococcus aureus, Staphylococcus epidermidis, Klebsiella oxytoca, Enterococcus faecalis, and Enterobacter cloacae on polyethylene, titanium, and stainless steel. We compared the quantities of biofilm formation between the bacterial species on the various biomaterials and the quantity of biofilm formation after various incubation times. Maggot excretions/secretions were added to existing biofilms to examine their effect. METHODS: Comb-like models of the biomaterials, made to fit in a 96-well microtiter plate, were incubated with bacterial suspension. The formed biofilms were stained in crystal violet, which was eluted in ethanol. The optical density (at 595 nm) of the eluate was determined to quantify biofilm formation. Maggot excretions/secretions were pipetted in different concentrations to (nonstained) 7-day-old biofilms, incubated 24 hours, and finally measured. RESULTS: The strongest biofilms were formed by S. aureus and S. epidermidis on polyethylene and the weakest on titanium. The highest quantity of biofilm formation was reached within 7 days for both bacteria. The presence of excretions/secretions reduced biofilm formation on all biomaterials. A maximum of 92% of biofilm reduction was measured. CONCLUSIONS: Our observations suggest maggot excretions/secretions decrease biofilm formation and could provide a new treatment for biofilm formation on infected biomaterials.

Cancellations of (helicopter-transported) mobile medical team dispatches in the Netherlands.

BACKGROUND: The trauma centre of the Trauma Center Region North-West Netherlands (TRNWN) has consensus criteria for Mobile Medical Team (MMT) scene dispatch. The MMT can be dispatched by the EMS-dispatch centre or by the on-scene ambulance crew and is transported by helicopter or ground transport. Although much attention has been paid to improve the dispatch criteria, the MMT is often cancelled after being dispatched. The aim of this study was to assess the cancellation rate and the noncompliant dispatches of our MMT and to identify factors associated with this form of primary overtriage. METHODS: By retrospective analysis of all MMT dispatches in the period from 1 July 2006 till 31 December 2006 using chart review, we conducted a consecutive case review of 605 dispatches. Four hundred and sixty seven of these were included for our study, collecting data related to prehospital triage, patient's condition on-scene and hospital course. RESULTS: Average age was 35.9 years; the majority of the patients were male (65.3%). Four hundred and thirty patients were victims of trauma, sustaining injuries in most cases from blunt trauma (89.3%). After being dispatched, the MMT was cancelled 203 times (43.5%). Statistically significant differences between assists and cancellations were found for overall mortality, mean RTS, GCS and ISS, mean hospitalization, length and amount of ICU admissions (p < 0.001). All dispatches were evaluated by using the MMT-dispatch criteria and mission appropriateness criteria. Almost 26% of all dispatches were neither appropriate, nor met the dispatch criteria. Fourteen missions were appropriate, but did not meet the dispatch criteria. The remaining 318 dispatches had met the dispatch criteria, of which 135 (30.3%) were also appropriate. The calculated additional costs of the cancelled dispatches summed up to a total of 34,448 euro, amounting to 2.2% of the total MMT costs during the study period. CONCLUSION: In our trauma system, the MMT dispatches are involved with high rates of overtriage. After being dispatched, the MMT is cancelled in almost 50% of all cases. We found an undertriage rate of 4%, which we think is acceptable. All cancellations were justified. The additional costs of the cancelled missions were within an acceptable range. According to this study, it seems to be possible to reduce the overtriage rate of the MMT dispatches, without increasing the undertriage rate to non-acceptable levels.

Prehospital identification of major trauma patients.

BACKGROUND AND AIMS: Prehospital triage is aimed at getting the right patient to the right hospital. Evaluations on the performance of prehospital triage tools are scarce. This study examines the ability of the American College of Surgeons' Committee on Trauma (ACSCOT) triage guidelines to identify major trauma patients in a European trauma system. Furthermore, this study evaluates the predictive power of other prehospital measurements. MATERIALS AND METHODS: Prehospital data of 151 minor (Injury Severity Score (ISS) 1-15) and 151 major trauma patients, (ISS > 15) treated at a Dutch trauma center, were collected. Logistic regression analysis was used to identify predictors of major trauma patients. RESULTS: The major trauma patients particularly incurred severe head injuries (45.7%) and severe thorax injuries (21.9%). The ACSCOT guidelines had a sensitivity of 84.1% and a specificity of 77.5%. A new prehospital trauma triage model was constructed including nine predictors of major trauma. This model identified more major trauma patients than the ACSCOT (sensitivity 92.1%, p = 0.023) and resulted in a comparable specificity (79.5%; p = 0.711). CONCLUSION: The new triage model outperforms the ACSCOT triage guidelines in identifying major trauma patients in the prehospital setting. The new triage guidelines may improve patient outcomes but needs to be validated in a prospective study.

Pediatric Splenic Injury: Nonoperative Management First!

BACKGROUND AND PURPOSE: In the past splenectomy was the standard procedure for traumatic blunt splenic injury, when bleeding of the spleen occurred. Since the spleen performs important immunological functions the advantage of a spleen-saving approach is preservation of immunological functions. Especially in the pediatric population splenic preservation is an important objective. Spleen-saving treatment, in particular selective nonoperative management, has gained ground in the past 20 years. An 18-year retrospective review was performed to evaluate our cumulative experience with nonoperative management. ENDPOINTS: hemodynamical instability and splenectomy. METHODS: Forty-six patients were identified. Demographics, methods of management, mechanism of injury, injury grade, associated injuries, hemodynamical parameters, bloodtransfusion, complications, ICU and hospital stay were documented and analyzed to determine statistical significance between modes of management. RESULTS: Initially, 34 patients were managed nonoperatively, while 12 patients underwent laparotomy - with 7 (58.3% of the operative group) of these having splenectomy performed. Three patients (out of 34) failed nonoperative management and required delayed splenorraphy or splenectomy, a 91.2% (3 out of 34 failed) success rate for intended nonoperative management versus 85.7% for intended splenorraphy (1 out of 7 failed). Thus, overall rates of 67.4% nonoperative management and 82.6% splenic conservation were achieved. Analysis of parameters between treatments showed significant differences between nonoperative management and splenorraphy for splenic injury grade II and IV. CONCLUSION: We recommend based on our data on children with splenic injury grades II and IV that the standard treatment for children aged 0 to 18 years due to blunt abdominal trauma should be nonoperative management. However management of blunt splenic injury remains a clinical decision, for this reason does not preclude on CT-scan grade V for nonoperative management.

Maggot excretions/secretions inhibit multiple neutrophil pro-inflammatory responses.

There is renewed interest in the use of maggots (Lucilia sericata) to aid in healing of chronic wounds. In such wounds neutrophils precipitate tissue damage rather than contribute to healing. As the molecules responsible for the beneficial actions of maggots are contained in their excretions/secretions (ES), we assessed the effects of ES on functional activities of human neutrophils. ES dose-dependently inhibited elastase release and H(2)O(2) production by fMLP-activated neutrophils; maximal inhibition was seen with 5-50 microg of ES/ml. In contrast, ES did not affect phagocytosis and intracellular killing of Candida albicans by neutrophils. Furthermore, 0.5 microg of ES/ml already inhibited neutrophil migration towards fMLP. ES dose-dependently reduced the fMLP-stimulated expression of CD11b/CD18 by neutrophils, suggesting that ES modulate neutrophil adhesion to endothelial cells. ES did not affect the fMLP-induced rise in [Ca(2+)](i) in neutrophils, indicating that ES act down-stream of phospholipase C-mediated activation of protein kinase C. In agreement, ES inhibited PMA-activated neutrophil functional activities. ES induced a rise in intracellular cAMP concentration in neutrophils and pharmacological activators of cAMP-dependent mechanisms mimicked their inhibitory effects on neutrophils. The beneficial effects of maggots on chronic wounds may be explained in part by inhibition of multiple pro-inflammatory responses of activated neutrophils by ES.

Prehospital triage and survival of major trauma patients in a Dutch regional trauma system: relevance of trauma registry.

BACKGROUND AND AIMS: Since 1999, the Dutch trauma care has been regionalized into ten trauma systems. This study is the first to review such a trauma system. The aim was to examine the sensitivity of prehospital triage criteria [triage revised trauma score (T-RTS)] in identifying major trauma patients and to evaluate the current level of trauma care of a regionalized Dutch trauma system for major trauma patients. PATIENTS AND METHODS: Major trauma patients (n=511) (June 2001-December 2003) were selected from a regional trauma registry database. The prehospital T-RTS was computed and standardized W scores (Ws) were generated to compare observed vs expected survival based on contemporary US- and UK-norm databases. RESULTS: The T-RTS showed low sensitivity for the prehospital identification of major trauma patients [34.1% (T-RTS< or =10)]. Nevertheless, 78.0% of all major trauma patients were directly managed by the trauma center. These patients were more severely injured than their counterparts at non-trauma-center hospitals (p<0.001). No significant difference emerged between the mortality rates of both groups. The Ws {-0.46 calculated on the US model [95% confidence interval (CI) ranging from -1.99 to 1.07]} [0.60 calculated on the UK model (95% CI ranging from -1.25 to 2.44)] did not differ significantly from zero. CONCLUSION: The trauma center managed most of the major trauma patients in the trauma system but the triage criteria need to be reconsidered. The level of care of the regional trauma system was shown to measure up to US and UK benchmarks.