Pulsatile Lavage Research Articles

Einfluss der Knochendichte und der Zementiertechnik auf die In-vitro-Zementverteilung in der Schulterendoprothetik

Loosening of the glenoid component is one of the major causes of failure in total shoulder arthroplasty. Possible risk factors for loosening of cemented components include an eccentric loading, poor bone quality, inadequate cementing technique and insufficient cement penetration. The application of a modern cementing technique has become an established procedure in total hip arthroplasty. The goal of modern cementing techniques in general is to improve the cement-penetration into the cancellous bone. Modern cementing techniques include the cement vacuum-mixing technique, retrograde filling of the cement under pressurisation and the use of a pulsatile lavage system. The main purpose of this study was to analyse cement penetration into the glenoid bone by using modern cement techniques and to investigate the relationship between the bone mineral density (BMD) and the cement penetration. Furthermore we measured the temperature at the glenoid surface before and after jet-lavage of different patients during total shoulder arthroplasty. It is known that the surrounding temperature of the bone has an effect on the polymerisation of the cement. Data from this experiment provide the temperature setting for the in-vitro study. The glenoid surface temperature was measured in 10 patients with a hand-held non-contact temperature measurement device. The bone mineral density was measured by DEXA. Eight paired cadaver scapulae were allocated (n = 16). Each pair comprised two scapulae from one donor (matched-pair design). Two different glenoid components were used, one with pegs and the other with a keel. The glenoids for the in-vitro study were prepared with the bone compaction technique by the same surgeon in all cases. Pulsatile lavage was used to clean the glenoid of blood and bone fragments. Low viscosity bone cement was applied retrogradely into the glenoid by using a syringe. A constant pressure was applied with a modified force sensor impactor. Micro-computed tomography scans were applied to analyse the cement penetration into the cancellous bone. The mean temperature during the in-vivo arthroplasty of the glenoid was 29.4 °C (27.2-31 °C) before and 26.2 °C (25-27.5 °C) after jet-lavage. The overall peak BMD was 0.59 (range 0.33-0.99) g/cm (2). Mean cement penetration was 107.9 (range 67.6-142.3) mm (2) in the peg group and 128.3 (range 102.6-170.8) mm (2) in the keel group. The thickness of the cement layer varied from 0 to 2.1 mm in the pegged group and from 0 to 2.4 mm in the keeled group. A strong negative correlation between BMD and mean cement penetration was found for the peg group (r (2) = -0.834; p < 0.01) and for the keel group (r (2) = -0.727; p < 0.041). Micro-CT shows an inhomogenous dispersion of the cement into the cancellous bone. Data from the in-vivo temperature measurement indicate that the temperature at the glenohumeral surface under operation differs from the body core temperature and should be considered in further in-vitro studies with human specimens. Bone mineral density is negatively correlated to cement penetration in the glenoid. The application of a modern cementing technique in the glenoid provides sufficient cementing penetration although there is an inhomogenous dispersion of the cement. The findings of this study should be considered in further discussions about cementing technique and cement penetration into the cancellous bone of the glenoid.

What Is the Benefit of Instillation Therapy?

Over the past decade, the concept of proper wound bed preparation as a means to improve wound healing has gained increasing attention. The principles of wound bed preparation include proper wound debridement, managing wound exudates, and managing bioburden. Proper wound bed preparation creates an optimal wound healing environment. The presence of necrotic tissue or eschar is known to impede healing. Likewise, the presence of abnormally high levels of bacteria may also impede healing. These impediments to wound healing may in part be removed by practices such as wound irrigation. Cleansing the wound by using an irrigant to remove loosely attached bacteria and cellular or other debris may decrease wound complications, thereby allowing the wound to heal in a timely fashion. Typically, wound irrigation is conducted at pressures less than 103.4 kPa using an irrigant that does not cause trauma to the surrounding tissue. Typical devices used to deliver irrigants to wounds include spray bottles, syringes, squeeze bottles, and pulsatile lavage devices. We consider all these types of approaches to fall under the category of instillation therapy. The clinical application of instillation therapy for treating wounds was first described by Fleischmann et al in 1998. Since then, several clinical articles have described various applications of instillation therapy, most of which address the treatment of wound infections. For example, Gabriel et al reported the use of instillation therapy for treating soft tissue infection. They showed that instilling silver nitrate was effective at reducing bioburden, time to wound closure, and time to hospital discharge. Others have followed with similar clinical results. Schintler et al and Timmers et al showed that instilling polyhexanide solution was effective at treating soft tissue necrotizing fasciitis and osteomyelitis. Even though the utility of wound irrigation for infected wounds is an accepted practice, cross-contamination from the splatter, which may be caused during the instillation process, is a safety concern to both the patient and the clinician. In a recent study, Angobaldo et al showed that bacteria from pulsatile lavage–treated wounds could be captured 3 feet away from the wound. The spread of organisms and especially resistant organisms in the hospital environment is a growing concern. Studies have demonstrated that methicillinresistant Staphylococcus aureus or vancomycin-resistant enterococci can be detected on the protective gowns and gloves of up to 67% of health care workers tested. With the increasing prevalence of antibiotic-resistant organisms and nosocomial infections, it is important that techniques be used to prevent the spread and possible cross-contamination of infection. This is especially true with any type of instillation therapy where outbreaks of infection have been traced back to facility contamination caused by the therapy itself. It is likely that such outbreaks could be prevented by better containment of splatter during the instillation procedure. In addition to the treatment of infection, there are a number of other potential uses for instillation therapy. The medical and scientific community recognizes additional clinical benefits for instillation therapy. Nagai et al reported that instilling the protein sericin has a potent effect on wound healing and corneal epithelialization in a rodent model. Jerome suggested using instillation therapy to provide pain management during and after dressing changes. The addition and removal of a liquid solution from a wound bed may have other clinical benefits. Instilling a wound with lactated Ringer’s solution or saline may dilute the bioburden and prevent potential clinical infections. At the same time, instillation therapy with saline may help remove necrotic tissues and reduce the level of proinflammatory mediators, leading to a shift toward the proliferative phase of healing. Reducing the amount of early inflammation may also lead to better tissue remodeling and tissue quality. Recently, Acosta et al postulated that chronic and hyperinflammation is detrimental to the repair of diabetic foot wounds. They highlighted the need for smart prophylactic interventions to reduce chronic inflammation. We believe that instillation therapy may address this clinical need for a therapeutic intervention. In summary, there are many benefits to applying instillation therapy in the treatment of wounds including lower extremity wounds. Depending on what solution is being instilled, instillation therapy can help resolve clinical infections, manage pain, reduce bioburden, and may even potentially aid in epithelialization. All these clinical benefits will help

Is the Use of Low-Pressure Pulsatile Lavage for Pressure Ulcer Management Associated With Environmental Contamination With Acinetobacter baumannii?

Ho CH, Johnson T, Miklacic J, Donskey CJ. Is the use of low-pressure pulsatile lavage for pressure ulcer management associated with environmental contamination with Acinetobacter baumannii? Objective To determine the extent of environmental contamination associated with low-pressure pulsatile lavage of stage III or IV pressure ulcers in patients with spinal cord injury (SCI) when routine infection control precautions are used for wounds colonized or infected with Acinetobacter baumannii. Design Prospective investigation in which pressure ulcer cultures and environmental cultures were obtained before and after low-pressure pulsatile lavage treatment, and before and after regular dressing changes. Environmental cultures included the patient's bedrail and settle plates placed 0.6, 1.5, and 2.4m from the wound to assess airborne spread of A. baumannii. Setting SCI inpatient unit in a Department of Veterans Affairs Medical Center. Participants Inpatients (N=15) with SCI receiving daily low-pressure pulsatile lavage treatment for stage III or IV pressure ulcers with standard dressing change, as well as regular dressing changes without low-pressure pulsatile lavage at other times of the day. Interventions Standard, regular dressing changes and dressing changes with low-pressure pulsatile lavage. Main Outcome Measures Comparison of frequency of environmental contamination with A. baumannii associated with low-pressure pulsatile lavage versus regular dressing changes. Results Of the 15 SCI inpatients meeting inclusion criteria, 9 (60%) grew A. baumannii from their wounds. Of the 9 patients with wound cultures positive for A. baumannii, only 1 (11%) had environmental contamination with this organism after performance of low-pressure pulsatile lavage, and the same patient had environmental contamination after a standard dressing change. The antibiotic susceptibility patterns of the wound and environmental A. baumannii isolates were identical. Conclusions Low-pressure pulsatile lavage using the infection control methods described is not associated with an increased rate of environmental contamination of A. baumannii in comparison with standard dressing changes.

Reduction of surgical site infections by use of pulsatile lavage irrigation after prolonged intra-abdominal surgical procedures

Background Surgical site infections cause significant postoperative morbidity and may be reduced by pressurized irrigation of high-risk laparotomy wounds before closure. This was a retrospective review (June 2007 to May 2008) from a surgical unit at a tertiary care center. Methods Patients undergoing laparotomy extending beyond 4 hours, when a standard wound management strategy was instituted by either simple irrigation or pressurized pulsatile lavage (<15 psi) with saline before closure, were included. The outcome measures were the surgical site infections and factors contributing to them. Results The median surgical time for the patients was 8 hours, with 34 wounds managed by simple irrigation and 42 wounds managed by pulse irrigation. Both groups had similar characteristics. Overall there were 15 (20%) surgical site infections. Significantly fewer infections occurred in the pulse irrigation group (10% vs 32%; P = .019). The use of a pulse irrigation device was the only factor associated with a reduction in wound infections ( P = .019). Conclusions Surgical site infections appear to be reduced with pulsatile lavage irrigation of wounds before skin closure in patients undergoing prolonged intra-abdominal surgeries.

QS211. Reduction of Surgical Site Infections by Use of Pulsatile Lavage Irrigation Device After Prolonged Intra-Abdominal Operative Procedures

QS211. Reduction of Surgical Site Infections by Use of Pulsatile Lavage Irrigation Device After Prolonged Intra-Abdominal Operative Procedures

A comparison between three irrigation methods in the debridement of contaminated bovine cancellous bone and the effect of duration of irrigation on the efficiency of debridement

Irrigation and debridement constitute an important part of treatment of open fractures. We investigated the efficiency of different irrigation methods and durations in cleansing contaminated bovine femur cancellous bone samples and the extent of tissue damage associated with irrigation. A total of 72 samples of 4x4x1 cm size were obtained from fresh frozen bovine distal femoral cancellous bone. The top surface of the samples were sawed to a 2-mm depth to create four squares equal in size. All the samples were contaminated with construction sand using the same method and were then randomized to three irrigation groups (bulb syringe irrigation, high-pressure pulsatile lavage, and low-pressure pulsatile lavage), each consisting of 24 samples. The duration of irrigation was set as 3, 6, or 9 minutes for every eight samples of each group. After the irrigation procedure, the images were transferred to a computer screen with a video-microscope camera and the number of sand particles on the samples were counted and irrigation-related macroscopic bone damage was assessed. The lowest number of sand particles was found on the samples irrigated by high-pressure pulsatile lavage (p<0.001). The duration of irrigation did not affect the efficiency of cleansing in all the groups (p>0.05). The least irrigation-related bone damage was observed in samples irrigated by low-pressure pulsatile lavage for 3 minutes (p<0.01). The amount of bone damage was similar in all groups after irrigations beyond 3 minutes (p>0.05). Our findings showed that the most efficient method of cleansing contaminated bone samples was high-pressure pulsatile lavage and that prolonged irrigations did not enhance the efficiency of the irrigation method; however, high-pressure irrigation of 3 minute duration resulted in the greatest bone damage.

Intraoperative monitoring for safety of total hip arthroplasty using third-generation cementing technique

Background Controversies on the safety of the cement application between cemented and uncemented total hip arthroplasty (THA) have been existing for decades. The purpose of this study was to observe the changes in mean arterial pressure (MAP), heart rate (HR) and oxygen pressure (PaO2) during cemented THA, and to evaluate the intraoperative safety of using the third-generation cementing technique and investigate whether the intraoperative risk is higher in acute femoral neck fracture patients than non-traumatic patients. Methods Forty-two patients who underwent cemented THA between November 2005 and September 2007 were prospectively included in this study. The third-generation cementing technique as vacuum mixing and pulsatile lavage was used strictly. The MAP and HR were monitored and documented during each operation. Blood gas analysis was performed at exposure, cup implantation, stem implantation and wound closure. MAP, HR and PaO2 were compared between pre- and post-cement application. Comparisons of MAP, HR and PaO2 between patients with acute femoral neck fracture and non-traumatic patiens were performed as well. Results No intraoperative cardiopulmonary complication occurred in these cases. No obvious changes were observed in MAP, HR and PaO2 after cement application. There was no significant difference in MAP, HR and PaO2 between acute femoral fracture patients (18 patients) and non-traumatic patients (24 patients). Conclusions The results of this study suggested that the invasive blood pressure monitoring and blood gas analysis are essential for patients undergoing cemented THA, especially for patients with femoral neck fracture. The third-generation cementing technique is safe to use in THA.

Comparison of Irrigation Solutions and Devices in a Contaminated Musculoskeletal Wound Survival Model

There is much to learn about the effectiveness of different methods currently used for the irrigation of open wounds. The purpose of this study was to compare various approaches in a survival animal model. We used an established goat model involving the creation of a reproducible complex musculoskeletal wound followed by inoculation with Pseudomonas aeruginosa (lux) bacteria. This genetically altered luminescent bacterium provides the ability for quantitative analysis with a photon-counting camera system. For Study 1, wound irrigation was performed six hours after the injury and inoculation; the goats were assigned to four treatment groups: normal saline solution, bacitracin solution, castile soap, and benzalkonium chloride. All wounds received sharp débridement and irrigation with use of a pulsatile lavage device (19 psi). Images and photon counts were obtained prior to irrigation, after irrigation, and forty-eight hours after injury and inoculation. For Study 2, we used the same animal model and compared bulb syringe and pulsatile lavage irrigation with saline solution. In Study 1, the irrigation treatment lowered the bacterial counts in all treatment groups. The greatest reduction was seen with castile soap, which lowered the photon count to 13% of the pretreatment level. This was followed by benzalkonium chloride, bacitracin, and saline solution at 18%, 22%, and 29%, respectively. At forty-eight hours, imaging showed a rebound in bacterial counts in every group. The highest rebound was measured in the castile soap group, which rebounded to 120% of the pretreatment level. The benzalkonium chloride group experienced a rebound to 94% of the pretreatment level. These were followed by bacitracin solution (89%) and normal saline solution (68%). In Study 2, both treatment methods were effective in removing 75% of the bacteria initially. At forty-eight hours, the bacterial levels in the pulsed lavage group rebounded to 94% of the original levels (compared with 48% in the bulb syringe group). The difference in the mean photon count ratios at forty-eight hours was significant (p = 0.048). Approaches used to remove bacteria from wounds, such as irrigants other than saline solution or high-pressure devices, may not have the best clinical outcome.

Irrigation With Potable Water Versus Normal Saline in a Contaminated Musculoskeletal Wound Model

Although the use of potable water for wound irrigation is attractive in an austere environment, its effectiveness has not been tested. We sought to compare the effectiveness of potable water irrigation in reducing bacterial number with that of normal saline irrigation. We used an established caprine model involving the creation of a reproducible complex musculoskeletal wound followed by inoculation with luminescent bacteria that allowed for quantitative analysis with a photon-counting camera system. Six hours after injury and inoculation, wound irrigations were performed using pulsatile lavage. Fourteen goats were randomized into two treatment groups: irrigation with 9 L potable water versus irrigation with 9 L normal saline. Images obtained after irrigation were compared with baseline images to determine the reduction in bacterial luminescence resulting from treatment. The irrigation in both groups reduced the bacterial counts by 71% from the preirrigation levels. Potable water reduced the bacterial load as effectively as normal saline in our model.

Mechanical Agitation and Serial Dilution –An Option for Anterior Cruciate Ligament Graft Sterilization

Contamination of tissue grafts can occur during anterior cruciate ligament reconstruction, necessitating decontamination. This study examined whether mechanical agitation and serial dilution provides greater bacterial eradication of experimentally contaminated bone-patellar tendon-bone grafts compared with antibiotic soak or pulsatile lavage. Forty bone-patellar tendon-bone grafts were contaminated with a bacterial suspension derived from operating room floor cultures. Four groups of specimens underwent immediate culture (control), antibiotic soak, pulsatile lavage, or mechanical agitation and serial dilution. The number of colony-forming units (CFU) for each group was statistically compared using t and chi-square tests. Each method of decontamination yielded a statistically significant reduction in CFU compared with the control. Analysis of positive versus negative cultures demonstrated a statistically significant difference between mechanical agitation and serial dilution compared with the other 2 methods. Mechanical agitation and serial dilution was the only method with 0 CFU and provided superior and consistent sterilization of experimentally contaminated grafts compared with antibiotic soak and pulsatile lavage.

Ultraclean air technology and pulsatile lavage irrigation for prevention of surgical site infection after lumbar spine fusion with instrumentation

Ultraclean air technology and pulsatile lavage irrigation for prevention of surgical site infection after lumbar spine fusion with instrumentation

Epidemiologic, Clinical, and Economic Evaluation of an Outbreak of Clonal Multidrug-ResistantAcinetobacter baumanniiInfection in a Surgical Intensive Care Unit

To determine risk factors for acquisition of multidrug-resistant (MDR) Acinetobacter baumannii infection during an outbreak, to describe the clinical manifestations of infection, and to ascertain the cost of infection. Case-control study. Surgical intensive care unit in a 400-bed urban teaching hospital and level 1 trauma center. Case patients received a diagnosis of infection due to A. baumannii isolates with a unique pattern of drug resistance (ie, susceptible to imipenem, variably susceptible to aminoglycosides, and resistant to all other antibiotics) between December 1, 2004, and August 31, 2005. Case patients were matched 1 : 1 with concurrently hospitalized control patients. Isolates' genetic relatedness was established by pulsed-field gel electrophoresis. Sixty-seven patients met the inclusion criteria. Case and control patients were similar with respect to age, duration of hospitalization, and Charlson comorbidity score. MDR A. baumannii infections included ventilator-associated pneumonia (in 56.7% of patients), bacteremia (in 25.4%), postoperative wound infections (in 25.4%), central venous catheter-associated infections (in 20.9%), and urinary tract infections (in 10.4%). Conditional multiple logistic regression was used to determine statistically significant risk factors on the basis of results from the bivariate analyses. The duration of hospitalization and healthcare charges were modeled by multiple linear regression. Significant risk factors included higher Acute Physiology and Chronic Health Evaluation II score (odds ratio [OR], 1.1 per point increase; P=.06), duration of intubation (OR, 1.4 per day intubated; P<.01), exposure to bronchoscopy (OR, 22.7; P=.03), presence of chronic pulmonary disease (OR, 77.7; P=.02), receipt of fluconazole (OR, 73.3; P<.01), and receipt of levofloxacin (OR, 11.5; P=.02). Case patients had a mean of $60,913 in attributable excess patient charges and a mean of 13 excess hospital days. Infection control measures included the following: limitations on the performance of pulsatile lavage wound debridement, the removal of items with upholstered surfaces, and the implementation of contact isolation for patients with suspected MDR A. baumannii infection. This large outbreak of infection due to clonal MDR A. baumannii caused significant morbidity and expense. Aerosolization of MDR A. baumannii during pulsatile lavage debridement of infected wounds and during the management of respiratory secretions from colonized and infected patients may promote widespread environmental contamination. Multifaceted infection control interventions were associated with a decrease in the number of MDR A. baumannii isolates recovered from patients.

An experimental comparison of different devices for pulsatile high-pressure lavage and their relevance to cement intrusion into cancellous bone

Some of the systems marketed for pulsatile high-pressure lavage are clearly different in their mechanical pulse characteristics. To take the matter further we set up an experimental in vitro model to determine whether these different lavage systems might produce different cementation results because of their differing pulse characteristics, and whether the systems differed significantly in terms of cement depth penetration. A total of 48 femoral heads were obtained at operation from patients who had undergone endoprosthetic hip replacement. The specimens were subjected to manual rinsing or semiautomatic cleansing procedures with five different pulsatile lavage devices. After the cleansing procedures, polymethylmetacrylate bone cement was intruded into the cancellous bone under standardised conditions. Determination of cement penetration was done by computed tomography using an image processing software. Irrespective of the nature of the lavage system tested, superficial cement penetration, both up to 2 mm and up to 3 mm, was significantly better after pulsatile high-pressure lavage than it was after manual rinsing of the specimens with a bladder syringe (P < 0.001 in each case). Whereas our experimental model did not show any significant differences between the lavage systems as regards the cementation results to a depth of up to 2 mm (P = 0.996), there were significant differences at a target depth of 3 mm (P < 0.05). As compared with manual rinsing, pulsatile high-pressure lavage in vitro makes highly significant improvements in cement penetration into cancellous bone and should be regarded as an indispensable component of modern cementation techniques for endoprosthetic surgery. Up to the present we have not been able to ascertain what influence the different pulse characteristics of a pulsatile lavage system may have on the intended cementation result, whether it is impact force, pulse shape, pulse duration, flow rate or frequency. Appropriate investigations will be necessary.

The effect of high and low pressure pulsatile lavage on soft tissue and cortical blood flow: a canine segmental humerus fracture model

To determine the effect of high pressure pulsatile lavage (HPPL) and low pressure pulsatile lavage (LPPL) on cortical and soft tissue blood flow in a canine humerus segmental fracture model. Midshaft humeral osteotomies to create a 2-cm segment of diaphyseal bone were performed on bilateral canine humeri. Each osteotomy site was irrigated using either high pressure (n = 6) or low pressure (n = 5) pulsatile lavage prior to stabilization with a 5-mm steinman pin. Perfusion of cortical bone, periosteum, and biceps muscle was measured using Laser Doppler Flowmetry during four intraoperative intervals: pre-osteotomy, post-osteotomy, post-lavage, and post-nailing. Following osteotomy, a significant drop occurred in cortical perfusion (HPPL P = 0.049, LPPL P = 0.021) and in periosteal flow (HPPL P = 0.019, LPPL P = 0.012). Following irrigation there was no significant decrease in blood flow in either group for muscle (HPPL P = 0.249, LPPL P = 0.41), periosteum (HPPL P = 0.381, LPPL P = 0.402), or cortex (HPPL P = 0.398, LPPL P = 0.352) measurements. There was no significant difference between irrigation groups in post-lavage perfusion values for muscle (P = 0.326), periosteum (P = 0.452), and cortex (P = 0.464). Cortical perfusion decreased significantly post-nailing (HPPL P = 0.027, LPPL P = 0.047). Measurements did not differ significantly between groups at any other time interval. Although previous work has demonstrated an association between HPPL and detrimental structural changes in bone, this study demonstrates that HPPL does not adversely affect cortical or soft tissue blood flow acutely. Further, LPPL offers no acute benefit to cortical or soft tissue perfusion.

Early Wound Irrigation Improves the Ability to Remove Bacteria

Although most surgeons prefer to treat contaminated wounds as soon as possible, the effect of timing on the ability of irrigation to reduce the amount of bacteria in a wound is not fully known. We evaluated the effect of different delays in irrigation on bacterial removal in an animal model. A complex musculoskeletal wound was created in the proximal part of the leg of goats. The wound was contaminated with Pseudomonas aeruginosa (lux) bacteria, genetically modified to emit photons, in order to allow for quantitative analysis of bacterial concentration with a photon-counting camera system. The contaminated wounds were closed, and wound irrigation was performed with 6 L of normal saline solution by means of pulsatile lavage after the assigned time-intervals of three, six, and twelve hours. Images were made before and after treatment. Relative luminescent units and clearance ratios were obtained and calculated for each wound. Earlier wound irrigation resulted in superior bacterial removal in our model. Irrigation resulted in a 70% +/- 2%, 52% +/- 3%, and 37% +/- 4% reduction in bacterial counts from the pre-irrigation level at three, six, and twelve hours, respectively. The clearance ratios were significantly different at all time-points (p < 0.004). Earlier irrigation in our contaminated wound model resulted in superior bacterial removal.

Experience With Wound VAC and Delayed Primary Closure of Contaminated Soft Tissue Injuries in Iraq

Wartime missile injuries are frequently high-energy wounds that devitalize and contaminate tissue, with high risk for infection and wound complications. Debridement, irrigation, and closure by secondary intention are fundamental principles for the management of these injuries. However, closure by secondary intention was impractical in Iraqi patients. Therefore, wounds were closed definitively before discharge in all Iraqi patients treated for such injures at our hospital. A novel wound management protocol was developed to facilitate this practice, and patient outcomes were tracked. This article describes that protocol and discusses the outcomes in a series of 88 wounds managed with it. High-energy injuries were treated with rapid aggressive debridement and pulsatile lavage, then covered with negative pressure (vacuum-assisted closure [VAC]) dressings. Patients underwent serial operative irrigation and debridement until wounds appeared clean to gross inspection, at which time they were closed primarily. Patient treatment and outcome data were recorded in a prospectively updated database. Treatment and outcomes data from September 2004 through May 2005 were analyzed retrospectively. There were 88 high-energy soft tissue wounds identified in 77 patients. Surprisingly, for this cohort of patients the wound infection rate was 0% and the overall wound complication rate was 0%. This series of 88 cases is the first report of the use of a negative pressure dressing (wound VAC) as part of the definitive management of high-energy soft tissue wounds in a deployed wartime environment. Our experience with these patients suggests that conventional wound management doctrine may be improved with the wound VAC, resulting in earlier more reliable primary closure of wartime injuries.

Debridement of Cancellous Bone: A Comparison of Irrigation Methods

This study tests the bone debridement efficacy and damage to cancellous bone produced by different wound irrigation methods. Cancellous bone slices of bovine distal femurs (3 cm x 3 cm) were divided into eight test groups and scored with a saw in a latticed pattern. Four test groups were contaminated with 1.0 g rock dust and four were not. The specimens were then treated as follows: no treatment (control), bulb irrigation, brush-suction irrigation, or high-pressure pulsatile lavage (HPPL). Runoff from the irrigation was collected, filtered, lyophilized, and ashed to allow for quantitative determination of organic and inorganic material removed from the bone by each irrigation method. The bone samples were subjected to blinded grading on two five-point scales to assess: 1) macroscopic tissue damage and 2) amount of contaminant remaining following treatment. Significantly more (P < or = 0.05) mean organic material was removed from samples treated with HPPL (744.8 +/- 120.0 mg) than with bulb syringe (115.2 +/- 11.9 mg) or brush-suction irrigation (95.1 +/- 9.2 mg). Brush-suction irrigation removed statistically significantly more (P < or = 0.05) of the 1.0 g of initial inorganic contaminant (937.7 +/- 6.3 mg) than bulb syringe irrigation (866.2 +/- 30.1 mg), while HPPL (900.2 +/- 19.0 mg) did not. Past studies have shown HPPL to damage both soft tissue and bone structure. The tissue damage that HPPL produces has been accepted in the past in exchange for its presumed superiority in contaminant removal. In this study, HPPL damaged samples more than other irrigation methods by removing significantly more organic material from them. However, HPPL and bulb syringe removed a statistically similar amount of inorganic contaminant, while brush-suction irrigation removed a significantly greater amount of inorganic contaminant than bulb syringe. It is proposed that HPPL may drive some contaminants deeper into the tissue rather than removing them, rendering HPPL not only more deleterious to bone structure and healing, but also less efficacious at removing contaminant than brush-suction irrigation.

Moderatorsʼ Summary: Amputee Care

Moderatorsʼ Summary: Amputee Care

Brain monitoring of apnea; antimicrobial surgical mask coating; stress and surgeon performance; pulsatile Lavage

Brain monitoring of apnea; antimicrobial surgical mask coating; stress and surgeon performance; pulsatile Lavage

Der Einfluss des Jet-Lavage-Systems auf das In-vitro-Zementierergebnis

The benefit of pulsatile lavage on cement penetration in femoral cancellous bone is well known. The aim of this study was to determine the influence of different jet-lavage systems on cement penetration in a standardized cadaver study. Four different jet-lavage systems were compared (right vs left) in 30 paired human femora. After broaching, the femoral canal was lavaged with 1 l saline. The specimens were embedded in plastic pots, bone cement was applied in a retrograde manner and cement was pressurized using a standard pressure protocol with a constant force of 3,000 N. Horizontal sections were obtained at predefined levels using an automatic saw. Microradiographs were taken and analysed using image analysis to assess the extent of cement penetration. There were no significant differences in cement penetration into cancellous bone using the different jet-lavage systems. This technique is of great importance for obtaining a good interdigitation with cancellous bone. The different jet-lavage systems investigated in our study, however, seemed to be equally effective.