Showing papers on "Surgical wound published in 1997"

Methicillin-resistant Staphylococcus aureus clinical strain with reduced vancomycin susceptibility.

Abstract: (MRSA) with reduced suscept-ibility to vancomycin (MIC 8 mg/L). The strain was isolated from a surgical wound infection which was refrac -tory to vancomycin therapy.In May 1996, a 4 month-old male infant underwent heartsurgery for pulmonary atresia. Two weeks followingsurgery, the infant became febrile and developed a purulent discharge from the sternal surgical incision site;culture of the purulent material yielded MRSA. The patientwas treated with vancomycin (45 mg/kg daily) for 29 days,but fever and discharge of pus continued, and the C-reactive protein (CRP) remained elevated (40 mg/L). Thetreatment was changed to a combination of vancomycin andarbekacin (an aminoglycoside approved for MRSA infec-tion in Japan). After 12 days of this regimen, the purulentdischarge subsided, the wound began to heal, and the CRPdeclined from 40 to 9 mg/L. The antimicrobial therapy wasdiscontinued. However, 12 days later the surgical siteappeared inflamed with the development of a subcutaneousabscess accompanied by a sudden onset of fever and a raised CRP level of 35 mg/L. Therapy was resumed with the com -bination of arbekacin and ampicillin/sulbactam which hasbeen shown to have synergic activity against MRSA.

Wound Tissue Oxygen Tension Predicts the Risk of Wound Infection in Surgical Patients

Abstract: Objective: To test the hypothesis that subcutaneous wound oxygen tension (PsqO2) has a predictive relation to the development of wound infection in surgical patients. Design: A noninterventional, prospective study. Setting: A university department of surgery. Patients: One hundred thirty operative general surgical patients at notable risk of infection as predicted by an anticipated Study on the Effect of Nosocomial Infection Control (SENIC) score of 1 or greater. Outcome Measures: PsqO2was measured perioperatively. Its relation to the subsequent incidence of surgical wound infection was then determined and compared with the SENIC score as a criterion standard. Results: Although the SENIC score and PsqO2are inversely correlated, PsqO2 is the stronger predictor of infection. Low PsqO2identified patients at risk and concentrated them in a cohort that was about half the size of that identified by the SENIC score. Conclusions: Subcutaneous perfusion and oxygenation are important components of immunity to wound infections. The SENIC score identifies systemic physiological variables that are important to the development of wound infection. Nevertheless, PsqO2More-he more powerful predictor of wound infection. Moreover, PPsqOcan be manipulated by available clinical means, and thus may direct interventions to prevent infection. Arch Surg. 1997;132:997-1004

Ability of chronic wound fluids to degrade peptide growth factors is associated with increased levels of elastase activity and diminished levels of proteinase inhibitors.

Abstract: The stability of peptide growth factors exposed to fluids from healing surgical wounds and from nonhealing chronic wounds was examined in vitro. (125)I-Labeled transforming growth factor-beta1 or platelet-derived growth factor-BB was incubated with fluids from healing surgical wounds and fluids from venous stasis or pressure ulcers. Fluids from healing surgical wounds had no appreciable effect on the level of (125)I corresponding to intact growth factor. In contrast, incubation with fluids from several venous stasis or pressure ulcers resulted in significant degradation of these growth factors. Degradation was blocked by broad-spectrum serine proteinase inhibitors and by specific inhibitors of neutrophil elastase. Levels of elastase activity in wound fluids correlated with the ability to degrade peptide growth factors. Further comparisons showed qualitative and quantitative differences in the endogenous proteinase inhibitors, alpha2-macroglobulin and alpha1-antiproteinase. These results could explain, in part, the variable growth factor levels which have been found in chronic wounds. More importantly, the ability of some chronic nonhealing wounds to rapidly degrade exogenously added growth factors has important implications with regard to past and future clinical attempts to use peptide growth factors to treat these types of problem wounds.

Management of postoperative infections after spinal instrumentation

Abstract: The authors retrospectively reviewed 452 consecutively treated patients who underwent a spinal instrumentation procedure at a single institution to establish which patients and which surgical approaches might be associated with an increased risk of developing deep wound infections and to determine the efficacy with which the institution's current treatment strategy eradicates these infections. Wound infections occurred in 17 patients (10 men and seven women) with spinal instrumentation (incidence 3.8%). All infections occurred after posterior spinal instrumentation procedures (7.2%); there were no infections after anterior instrumentation procedures regardless of the level. Each patient was assigned an infection risk factor (RF) score depending on the number of RFs identified in an individual patient preoperatively. The mean RF score of patients who developed infections was 2.18, whereas the mean RF score for a procedure-matched, infection-free control group was 0.71. The mean number of days from surgery to clinical presentation was 27.6 days (range 4-120 days), and the mean increase in hospitalization time for the subset of patients who developed infections was 16.6 days. The most common organism isolated from wound cultures was Staphylococcus aureus (nine of 17 cases). Of the 17 patients, five had infections involving multiple organisms. All patients were infection free at a minimum of 8 months follow-up review. The current treatment regimen advocated at this institution consists of operative debridement of the infected wound, a course of intravenous followed by oral antibiotic medications, insertion of an antibiotic-containing irrigation-suction system for a mean of 5 days, and maintenance of the instrumentation system within the infected wound.

Sternal wound complications - Incidence, microbiology and risk factors'

Abstract: Objective: Sternal wound complications, i.e. instability and/or infection (mediastinitis), are important causes of morbidity in patients undergoing cardiac surgery via median sternotomy. Coagulase negative staphylococci, a normal inhabitant of the skin, have evolved as a cause of sternal wound infections. Since these opportunistic pathogens often are multiresistant, they can cause therapeutic problems. Methods: From 1980 through 1995 open heart surgery, was performed on 13,285 adult patients. Reoperation necessitated by sternal wound complications occurerd in 203 patients (1.5%). The incidence was 1.7% 168/9987) after coronary artery bypass grafting (CABG group) and 0.7% (35/3413) after heart valve surgery with or without concomitant CABG (HVR group). Results: Factors independently related to sternal complications in the CABG group (variable odds ratio [95% C.I.]) : year of surgery, 1.9 [1.3-2.8] in 1990-1992, 2.0 [1.4-2.9] in 1993-1995; female sex, 0.4 [0.2-0.6]; diabetic disease, 1.8 [1.2-2.5]; bilateral ITA procedure, 3.3 [1.1-7.7]; and postoperative dialysis, 3.1 [1.4-6.9]. In the HVR group they were: use of ITA graft, 3.7 [1.7-7.7]; early re-exploration because of bleeding 3.0 [1.1-8.2]; and postoperative dialysis 3.1, [1.4-9.3]. Multivariate models were used to compute the risk for sternal complications in each patient. However, the prognostic models based on these risk scores provided low sensitivity and low predictive value. Patients with sternal wound complications showed no increased early mortality but worse long-term survival even after adjustment for other factors (relative hazard in CABG group 1.9 [1.2-2.8]; in HVR group 2.1 [1.1-4.3]. Conclusions: The use of ITA grafts seems to be one of the most important factors related to sternal wound complications. However, patients at truly increased risk for this complication could not be identified on the basis of the risk factors considered in this study.

Gasless laparoscopy may reduce the risk of port-site metastases following laparascopic tumor surgery.

Abstract: Objective: To compare the incidence of port-site metastases in an experimental tumor model following tumor manipulation during laparoscopy aided by conventional insufflation with laparoscopy using a gasless technique. Setting: An experimental model applied in a research laboratory. Participants and Interventions: Malignant tumors were implanted in the abdominal wall of 24 rats. Twelve rats underwent tumor laceration at laparoscopy with carbon dioxide insufflation, and 12 rats underwent the same procedure during gasless laparoscopy achieved by abdominal wall suspension. Rats were killed 1 week later and were examined for evidence of tumor metastases. The surgical wounds were examined microscopically by a histopathologist who was unaware of the operative technique used and the site of origin of the specimens. Main Outcome Measure: Histologically confirmed tumor metastasis to laparoscopic port wounds. Results: Growth of the primary tumor was equal in both groups. Wound metastases were less likely in the gasless laparoscopy group (3 of 12 vs 10 of 12; P =.01, Fisher exact test). Conclusion: The use of laparoscopy without gas insufflation may reduce the risk of wound metastasis following laparoscopic surgery for cancer. Arch Surg. 1997;132:166-168

Infektbehandlung durch Vakuum-versiegelung

Abstract: Vom 01.01.1992 bis zum 31.07.1995 wurden 313 Patienten mit akuten und chronischen Infektionen durch Vakuumversiegelung (VVS) behandelt. Die durchschnittliche Dauer der Versiegelungen betrug 16,7 Tage, und es erfolgten im Mittel 3,1 Wechsel des Versiegelungssystems. Der Abschlus der Behandlung bestand bei akuten Infekten (n = 203) aus Sekundarnaht (65,5%), spontaner Epithelisierung (17,2%), Hauttransplantationen (12,3%) und Lappenplastiken (2%); 6 Patienten starben (3%). Bei 3,9% traten Infektrezidive auf, die durch VVS ausbehandelt wurden. Instabile Narbenbildungen (1%) wurden durch freie mikrovaskulare Lappen beseitigt. Die kostengunstige VVS bietet gegenuber der offenen Wundbehandlung Vorteile im Hinblick auf Krankenhaushygiene, Patientenkomfort und Behandlungsergebnis.

Postoperative Serratia marcescens wound infections traced to an out-of-hospital source.

Abstract: From 25 August to 28 September 1994, 7 cardiovascular surgery (CVS) patients at a California hospital acquired postoperative Serratia marcescens infections, and 1 died. To identify the outbreak source, a cohort study was done of all 55 adults who underwent CVS at the hospital during the outbreak. Specimens from the hospital environment and from hands of selected staff were cultured. S. marcescens isolates were compared using restriction-endonuclease analysis and pulsed-field gel electrophoresis. Several risk factors for S. marcescens infection were identified, but hospital and hand cultures were negative. In October, a patient exposed to scrub nurse A (who wore artificial fingernails) and to another nurse-but not to other identified risk factors-became infected with the outbreak strain. Subsequent cultures from nurse A's home identified the strain in a jar of exfoliant cream. Removal of the cream ended the outbreak. S. marcescens does not normally colonize human skin, but artificial nails may have facilitated transmission via nurse A's hands.

Effect of NSAID administration on tissue levels of immunoreactive prostaglandin E2, leukotriene B4, and (S)-flurbiprofen following extraction of impacted third molars

Abstract: Post-operative pain and inflammation are frequently managed with non-steroidal anti-inflammatory drugs (NSAIDs). Despite the prevalence of their use, however, relatively little is known about in vivo tissue concentrations of inflammatory mediators at the site of tissue injury and their modulation by NSAIDs. This study compares the effect of oral administration of the NSAID flurbiprofen, to placebo, on tissue levels of immunoreactive prostaglandin E2 (iPGE2), leukotriene B4 (iLTB4), and (S)-flurbiprofen within the surgical wound using implanted microdialysis probes in the dental impaction pain model. Twenty-four healthy patients in need of extraction of partial to complete bony mandibular third molars were recruited for this randomized, double-blind, placebo-controlled study. Following pre-operative administration of N2O/O2, midazolam i.v., and regional block anesthesia with 3% mepivacaine, each patient underwent surgical removal of their impacted third molars. Immediately following completion of the surgery, two semi-permeable microdialysis probes (3 kDa molecular weight cut-off) were implanted into each mandibular surgical site. Patients were taken to a recovery room and microdialysis samples and patient pain reports (visual analog scale, VAS) were collected at 30 min intervals for 4 h. Patients randomly received either flurbiprofen (200 mg orally) or placebo at the onset of post-operative pain. Dialysate samples were collected, frozen, and later assayed for iPGE2, iLTB4, and (S)-flurbiprofen levels. Results of this study show that flurbiprofen decreased post-operative pain by approximately 70% compared to placebo-treated patients (P < 0.001). During the 4 h post-operative timecourse of this study, flurbiprofen treatment significantly reduced peak tissue levels of iPGE2 (9.2 +/- 2.6 vs. 0.4 +/- 0.15 nM; P < 0.001), without having a significant effect on peak tissue levels of iLTB4 (2.5 +/- 1.4 vs. 1.49 +/- 0.86 nM) compared to placebo treatment. Levels of (S)-flurbiprofen significantly increased within the surgical wound exceeding therapeutic levels by 60 min after administration. Flurbiprofen is able to significantly suppress the local production of iPGE2 and provide significant analgesic efficacy without altering iLTB4 tissue levels in this model of acute post-operative inflammatory pain. These data indicate that NSAIDs selectively alter eicosanoid levels within surgical wound and evoke analgesia at time points coincident with elevated wound levels of the drug. The combined use of microdialysis probes in awake patients who provide simultaneous pain reports may offer insight into peripheral mechanisms of inflammatory mediator release and pain.

Silver aids healing in the sterile skin wound : experimental studies in the laboratory rat

Abstract: Incisional wounds 15 mm long were induced surgically in the back skin of young adult Wistar rats. They were sutured and used as an experimental model in the therapeutic evaluation of daily applications of 0.5 mL of silver nitrate (SN) at 0.01, 0.1 or 1.0% w/v aqueous solution, or 0.5 g silver sulphadiazine (SSD) over a 10-day period. Control wounds received deionized water only. The silver preparations were not toxic but SN did stain the hair and superficial layers of the stratum corneum. The wounds remained microbiologically clean. Wounds exposed to SN (0.1 or 1.0%) or SSD healed more rapidly than controls. From about the fourth day of treatment, we noted a more rapid exteriorization of sutures, improved wound closure and an earlier loss of scabs and wound debris. Silver treatment appeared to reduce the inflammatory and granulation tissue phases of healing and enhance epidermal repair. Silver from SN was deposited as silver sulphide in extrafollicular hair shafts and superficial aspects of the skin and wound debris but not at deeper levels. Silver uptake was four-fold higher in damaged skin than in intact tissue. SSD was absorbed by intact and wounded skin but the silver did not precipitate as silver sulphide and its localization in the tissue is not known. Uptake of silver from SN or SSD was associated with changes in the concentrations of zinc and calcium in the skin. Zinc levels were depressed during the inflammatory and proliferative phases of healing and then increased. Zinc concentrations had normalized by 10 days when wound healing was achieved. Calcium levels remained higher than normal throughout the observation period. The mechanism of action of silver in advancing wound healing in the rat is unclear. Its ability to reduce the inflammatory and granulation phases of healing, and to invoke metallothionein production and influence metal ion binding are possibly important.

The effect of laparoscopy on the movement of tumor cells and metastasis to surgical wounds

Abstract: Background: A variety of mechanisms have been proposed to explain tumor growth in port sites following laparoscopic cancer surgery. We devised two experimental models to determine whether carbon dioxide (CO2) insufflation during laparoscopic surgery influences the movement of tumor cells and leads to tumor implantation and growth in surgical wounds.

Molecular cell biology for the refractive corneal surgeon: programmed cell death and wound healing.

Abstract: BACKGROUND Variability of outcome following refractive surgical procedures is affected by corneal wound healing Interactions between the corneal epithelium and stromal keratocytes affect both stromal remodeling and healing of the epithelium These processes contribute to regression of initial effect, surface irregularity, and stromal scarring that occur following excimer laser photorefractive keratectomy (PRK) I review recent discoveries related to stromal-epithelial molecular interactions that provide insights into the cellular responses to refractive surgical procedures RESULTS Injury to the corneal epithelium stimulates programmed cell death (apoptosis) of the underlying anterior stromal keratocytes I hypothesize that apoptosis of the keratocytes occurring immediately after epithelial injury associated with refractive surgical procedures initiates the subsequent wound healing response Activated keratocytes subsequently repopulate the anterior corneal stroma where they produce collagen and other components associated with stromal remodeling In addition, secretion of hepatocyte growth factor and keratinocyte growth factor by keratocytes increases after corneal epithelial wounding and these growth factors stimulate proliferation and inhibit differentiation of epithelial cells, effects which could promote epithelial hyperplasia associated with regression after photorefractive keratectomy CONCLUSION Corneal stromal-epithelial interactions help explain the different results that occur following excimer laser photorefractive keratectomy and laser in situ keratomileusis

Wound Infections Following Spinal Fusion with Posterior Segmental Spinal Instrumentation

Abstract: Twenty-three of 238 patients (9.7%) developed wound infections following segmental spinal instrumentation. When the infected group and a matched control group were compared, the infected group had a significantly higher number of patients with cerebral palsy and myelodysplasia (non-ambulatory), patients with wound hematomas, patients with fusions that extended into the sacral region, and patients who were incontinent of urine. A high incidence of infections with gram-negative aerobic bacilli correlated with the extension of the surgery into the sacral region and bowel andlor bladder incontinence. Prophylactic antibiotics with broader coverage for gram-negative bacilli may be warranted for these procedures. Postoperative wound infections were managed by surgical drainage and debridement as well as antibiotics. Removal of the hardware was not necessary to control the infection in these patients who underwent segmental spinal instrumentation.

Effect of Prednisolone on the Systemic Response and Wound Healing After Colonic Surgery

Abstract: Objective: To study the effect of preoperative treatment with a single high-dose glucocorticoid on the systemic and immunologic responses, wound healing, and convalescence after colonic surgery. Design: Double-blind, placebo-controlled, randomized trial. Setting: Department of surgery in a university hospital. Patients: Thirty patients scheduled for open colonic resection; 6 patients were excluded from the study (N=24). Interventions: Patients were randomized to either of 2 treatment regimens: methylprednisolone sodium succinate 90 minutes before induction of anesthesia and epidural analgesia (group 1, n=12), or placebo 90 minutes before anesthesia and epidural analgesia (group 2, n= 12). Main Outcome Measures: Assessments of pain, pulmonary function, convalescence, and various injury and wound-healing factors were done several times until 10 days after surgery. Results: Conventional reduction in pulmonary function and mobilization was improved in group 1. Interleukin-6 and C-reactive protein levels increased significantly less in group 1, as delayed-type hypersensitivity was abolished in group 1. Plasma cascade system activations were significantly less pronounced in group 1. Reduction of collagen turnover was observed in group 1, but without detrimental effects on collagen accumulation. Conclusion: Treatment with a single high-dose glucocorticoid before colonic surgery may improve postoperative pulmonary function and mobilization and reduce plasma cascade system activations, the inflammatory response, and immunofunction, but without detrimental effects on wound healing. Arch Surg. 1997;132:129-135

Adverse impact of pneumoperitoneum on intraperitoneal implantation and growth of tumour cell suspension in an experimental model.

Abstract: Background: An investigation of the effect of laparoscopy and CO2 pneumoperitoneum on the pattern of tumour implantation and growth in the peritoneal cavity was carried out. Methods: A suspension of viable adenocarcinoma cells was introduced into the left upper quadrant of the peritoneal cavity of 36 syngeneic immune-competent rats at laparotomy, laparoscopy with CO2 insufflation, and gasless laparoscopy (12 rats in each group). Six days later the peritoneal cavity and surgical wounds were examined for macroscopic evidence of implanted tumour. The abdominal cavity was divided into sectors and macroscopic tumour implantation was determined for each sector and wound. This was confirmed by histological examination. Results: While tumour implantation occurred in the vicinity of the tumour suspension introduction site in the laparotomy and gasless laparoscopy groups, implantation occurred throughout the peritoneal cavity, including areas remote to the introduction site, in the laparoscopy with CO2 insufflation group. Tumour growth was more likely in the port wounds of rats undergoing laparoscopy with insufflation than without. Conclusions: In this model, CO2 insufflation during laparoscopy resulted in widespread tumour dissemination and implantation, when compared to laparotomy and gasless laparoscopy, supporting the postulate that wound metastasis and tumour spread may be more likely following laparoscopic cancer surgery in humans when CO2 insufflation is used.

Cell and matrix reactions at titanium implants in surgically prepared rat tibiae.

Abstract: The tissue response of rat tibiae to the surgical placement of commercially pure titanium implants was examined at 2, 6, 10, and 28 days. The transcortical placement of 1.5-mm x 2-mm implants resulted in the apposition of threaded implant surfaces within cortical and cancellous regions of the tibia. In all regions, evidence of bone formation was obtained through pre-embedding fracture of the implant from the bone tissue interface. Scanning electron microscopy examination of early responses revealed a fibrin clot and rapid formation of a loosely organized collagenous matrix. Many extravasated blood cells contacted the implant surface. At day 6, a more organized matrix containing many blood vessels opposed the implant surfaces, and few extravasated blood cells remained in contact with the implant surface. By day 10, the surgical wound was filled with woven bone that approximated the contours of the threaded implant. Later, few cells were attached to the retrieved implants. The consolidation of the forming matrix was clearly evident at 28 days. The tissue interface was an amorphous matrix that revealed the surface characteristics of the machined implant. Light microscopic analysis of ground sections indicated that, from day 6 onward, cells morphologically consistent with the osteoblastic phenotype were predominant within the gap between the surgical margin and implant surface. Osteoblastic cells had achieved the formation of an osteoid seam upon which bone formation progressed. The matrix that had formed represented woven bone containing many osteocytes. At day 6, evidence of remodeling was observed at sites distant from the surgical site, and by day 28 osteoclastic activity was observed at trabecular sites adjacent to the implant surface. The rat tibia model provides evidence of rapid formation of bone at implant surfaces.

Postsurgical wound progression monitored by temporal changes in the expression of matrix metalloproteinase‐9

Abstract: It is important to monitor the early stages of postoperative wound repair in order to identify those problems associated with impaired healing. Many of the crucial cellular responses of early wound healing, such as inflammatory infiltration, angiogenesis and re-epithelialization, are made possible through the action of matrix metalloproteinases (MMPs). Expression of MMP-2 and MMP-9 is elevated in acute wounds, and still greater levels are found in chronic wounds, indicating that uncontrolled proteolysis is a characteristic of retarded healing. Therefore, comparative measurements of MMPs may be used to monitor the progression of early wound healing. To investigate this, wound fluids and sera were collected from mastectomy and colectomy patients throughout early stages of repair, and the temporal expression profile established. Wounds which were healing were expressed maximal levels of MMP-9 at 24 h, followed by a significant decline by 48 h. Persistent elevation of MMP-9 expression was associated with infected and chronic wounds, and was identified in postoperative wounds by the absence of the significant decline between 24 and 48 h. Measurement of MMP-9 in postoperative wound fluids, therefore, provides an early indicator of impaired healing, which may be evaluated non-invasively within 48 h of closure.

Risk factors for surgical-wound infection in general surgery: a prospective study.

Abstract: Objective To quantify surgical-infection rate, to assess adherence with the antibiotic prophylaxis protocol, and to identify independent factors associated with surgical-wound infection (SWI). Methods We carried out a prospective study of a cohort of 2,237 general surgery patients with postsurgery stays of more than 48 hours. Odds ratios (OR) were estimated using unconditional multiple logistic regression. Setting A 1,300-bed, university-affiliated, tertiary-care hospital in Madrid, Spain. Results 254 patients developed SWI. The rate of adherence to the antibiotic prophylaxis protocol was 63.5%. Eight factors were independently associated with risk of SWI: age (OR = 1.2 for every 10 years of age); wound classification (clean-contaminated, OR = 6.4; contaminated, OR = 3.7; dirty or infected, OR = 9.3); antimicrobial prophylaxis (OR = 0.5); stay prior to surgery (OR = 1.1 for every 3 days); duration of operation (OR = 1.5 for every 60 minutes); malignant neoplasm (OR = 1.7); emergency procedure (OR = 1.99); intensive-care unit stay prior to surgery (OR = 2.6); and antimicrobial prophylaxis administered 2 or more hours before operation (OR = 5.3). Conclusion In general, antimicrobial prophylaxis protects against SWI (OR = 0.5); however, administration 2 hours or more before the operation increases the risk of SWI by a factor of 5.3. Therefore, measures should be taken to ensure the correct timing of antimicrobial prophylaxis.

Proliferative response of human and animal tumours to surgical wounding of normal tissues: onset, duration and inhibition.

Abstract: Acceleration of secondary tumour growth and metastases following excision of a primary tumour has been attributed to the consequent removal of primary tumour-generated inhibitory factors. However, our studies have shown that surgical wounding of normal tissues significantly stimulated the growth of malignant tissues without the concomitant presence or excision of a tumour mass. A humoral stimulating component was indicated by the proliferative response of tumours and metastases distant from the surgical wound. All 16 human and murine tumours, of nine different histologies, showed a measurable acceleration of growth when implanted in surgically treated animals, suggesting that the ability of malignant tissue to respond to surgical wounding of normal tissue was not histologically or species specific. The proliferative surge of malignant tissues was detectable soon after wounding and had a duration of 2-3 days. The surgical wound as the source of the tumour-stimulating factor(s) was affirmed by the significant inhibition of tumour proliferative responses when a somatostatin analogue was applied topically to the surgical wound within 1 h of wounding, and/or during the critical tumour-stimulatory period of 1-2 days after wounding. A potential therapeutic window for reducing a risk factor that may be inadvertently imposed upon every surgical/oncology patient is indicated.

Basics of surgical-site infection surveillance.

Abstract: Surgical-site infections, the third most common class of nosocomial infections, cause substantial morbidity and mortality and increase hospital costs. Surveillance programs can lead to reductions in surgical-site infection rates of 35% to 50%. Herein, we will discuss the practical aspects of implementing a hospital-based surveillance program for surgical-site infections. We will review surveillance methods, patient populations that should be screened, and interventions that could reduce infection rates.

Shaving of the Scalp May Increase the Rate of Infection in CSF Shunt Surgery

Abstract: Hydrocephalic patients undergo repetitive surgical procedures, most of which involve the scalp. 141 shaveless operations involving scalp incisions for cerebrospinal fluid (CSF) shunts as well as 218 historical controls were reviewed after the senior author ceased shaving the scalp. The study population has been followed for a mean of 13.4 months and the control population for a mean of 38.6 months. The actuarial rate of infection at 1 year was 3.3% in the study population and 6.9% in the control population. Anesthesia times were not significantly different. Shaving of the scalp is not a critical step in the prevention of CSF shunt infection.

Time course of subjective pain ratings, and wound and leg tenderness after hysterectomy

Abstract: Background: Little information is available on time course of wound tenderness and relationship to subjective pain ratings following surgery. Furthermore, it is not clarified whether surgical procedures may induce hyperalgesia to mechanical stimulation outside the area of the surgical incision. We have therefore assessed postoperative pain and pressure pain thresholds (PPT) adjacent to and remote from the surgical incision in 16 patients undergoing hysterectomy. Methods: Pressure pain threshold was assessed with pressure algometry preoperatively, 4 and 6 h and 1, 4 and 8 d after surgery on the abdominal wall 0.5, 5, 10 and 15 cm perpendicular to the wound, and on the anterior surface of the left thigh and tuberositas tibia. Furthermore, pain was assessed on a visual analogue scale (VAS) at rest and during cough. Results: PPT decreased significantly 0.5, 5, 10 and 15 cm from skin incision up to 96 h after surgery (P < 0.01) with a trend towards higher PPT with increasing distance from the wound. There was no significant changes in PPT on the thigh or the tuberositas tibia (P = 0.49 and P = 0.12) and no correlation be tween changes in PPT near the wound and in remote areas (the legs) (Rs=-0.082, P = 0.44 and Rs=-0.0664, P = 0.53, respectively). VAS at rest increased from 4 to 24 h and the cough values, remained elevated throughout the study (P < 0.05). An inverse relationship was observed between PPT 5 cm from the incision and VAS at rest (Rs=-0.406, P = 0.0002) and during cough (Rs=-0.398, P = 0.0002). Conclusion: These results indicate that wound pressure algometry correlates to postoperative pain at rest and during movement and may be an alternative way of assessing wound pain and tenderness. Increased tenderness to mechanical stimulation remote from the surgical wound could not be demonstrated.

Effect of timing of postoperative chemotherapy on survival of dogs with osteosarcoma

Abstract: BACKGROUND After excision of primary tumors, initiation of chemotherapy for micrometastases is often delayed for 2 to 4 weeks to permit patient recovery and early healing of the surgical wound. However, studies using murine tumors have indicated that removal of a primary tumor may cause increased cell proliferation within micrometastases during the first 7 to 10 days after surgery, potentially rendering the micrometastases more susceptible to chemotherapy. Clinical trials assessing the value of early postoperative initiation of chemotherapy for human breast carcinoma have yielded conflicting results. Osteosarcoma of dogs is a naturally occurring model for human tumors likely to have micrometastases at the time of diagnosis. METHODS Before surgery, 102 dogs with osteosarcoma were randomized to receive cisplatin and doxorubicin chemotherapy beginning either 2 days or 10 days after amputation. Survival analysis was performed for each treatment group and for a historic control group comprised of 162 dogs treated by amputation alone. RESULTS Median survival times for dogs treated by amputation alone and for dogs receiving chemotherapy beginning 2 or 10 days after surgery were 5.5, 11.5, and 11.0 months, respectively. Survival was significantly longer for each of the two groups of dogs receiving chemotherapy than for control dogs (P < 0.0001). There was no significant difference in survival between treatment groups (P = 0.727). CONCLUSIONS These results do not disprove the theory that removal of a primary tumor alters the growth kinetics of metastases, but do imply that there is no substantial advantage to early postoperative initiation of adjuvant chemotherapy for spontaneous tumors of large species. Cancer 1997; 79:1343-50. © 1997 American Cancer Society.