Charles John Palenik

Effect of Surgical Safety Checklists on Postoperative Morbidity and Mortality Rates, Shiraz, Faghihy Hospital, a 1-Year Study

Objective: The study intent was to (1) encourage the use of surgical safety checklists and (2) measure the effect checklists have in reducing surgical complications. Design: An interventional study designed to improve postsurgical outcomes was performed. Setting: The study site was a 374-bed referral educational hospital in Shiraz, Iran, with 6 operating rooms. The study lasted 6 months. Participants: Patient selection involved a convenient sampling method with all eligible patients entering. Intervention: Our checklist covered 3 surgical stages-–before anesthesia, immediately before an incision, and before moving the patient to a recovery room. Persons included were operating room team members. Main outcome measures: Rates of postsurgical complication before and after application of the surgical safety checklist underwent comparison. Results: Incidence of any complication before and after intervention was 22.9% and 10% (P = .03). Five checklist items were in total compliance. The most common complication was surgical site infection. Implementation of the checklist, responsibility in 2 stages, such as time out and sign out, were significant (P < .05). In most cases, these items reflected the performance of surgeons and anesthesia professionals as compared with the World Health Organization Surgical Safety Checklist. Conclusion: Complications decreased by 57% after intervention. Both high patient information detection and elevated levels of cooperation by surgical personnel were observed. Compliance likely helped prevent some adverse effects associated with surgery.

Inhibition of microbial adherence and growth by various glass ionomers in vitro.

This study measured the in vitro inhibition of growth and adherence of five oral bacteria by glass-ionomer materials. Disks were prepared from two cavity liners and four restorative class materials, by use of Teflon plates with circular wells, five mm wide and two mm deep. The bacterial species tested included: A. viscosus, S. mitis, S. mutans, L. casei, and S. sanguis. Growth inhibition studies were performed by the spreading of 0.1 mL of standardized inocula over agar plates produced with selective media, followed by the direct application of glass-ionomer disks onto the agar. On other plates, disks were placed onto uninoculated agars for 48 h, followed by bacterial inoculation. All agar plates were incubated under optimal growth conditions for each bacterial species. The four restorative materials were also placed aseptically into sterilized bovine incisors and placed into sucrose containing broth media, inoculated with S. mutans for three days. Adhering materials were disclosed and scored. An ion-exchange electrode was used to measure fluoride release over a seven-day period for all six glass ionomers. The two cavity liners and two of the restorative materials produced the largest growth inhibition zones by direct contact. No growth inhibition occurred when the specimens were allowed to come into contact with the agars prior to inoculation. All four restorative materials reduced bacterial accumulations on enamel surfaces by over 80%. Elevations in short-term fluoride release levels were positively correlated with growth inhibition.

A survey of sterilization practices in selected endodontic offices

Little information exists concerning the effect(s) office asepsis procedures can have on sterilization success in dental speciality offices. Therefore, 218 randomly selected private endodontic offices in five midwestern states were sent spore strips, use instructions, and a 16-question survey. The question-naire dealt with practitioner/auxillary training, continuing education practices, and office sterilization procedures. Offices returning “positive” spore strips were sent additional strips and guidelines for improving sterilizer performance. Survey data were compared with sterilizer type and spore killing results. A total of 139 sterilizers in 106 offices was monitored. Testing results indicated a 15.1% overall failure rate. Of the offices with sterilization failures, only 68.2% responded for retesting. However, all of the responding offices eventually achieved negative spore tests. Dry heat ovens were most likely to have a sterilization failure (p

The use of paraformaldehyde powder for the sterile storage of gutta-percha cones

This investigation was undertaken to determine whether the use of paraformaldehyde powder for the sterile storage of gutta-percha cones is necessary, effective, and safe. Gutta-percha cones from unopened manufacturers packages (Hygienic) were found to be sterile and to possess no inherent antimicrobial properties. Paraformaldehyde powder placed within the storage container was ineffective in sterilization of cones contaminated by bacterial endospores. Such storage did not prevent contamination of cones by air-borne agents, but storage in a covered glass container without paraformaldehyde was equally effective. Formaldehyde was found to be adsorbed onto the surface of cones exposed to formaldehyde vapors. No significant increase in the level of formaldehyde in the operatory air was detected as a result of this storage method. It is recommended that this method of “sterile storage” be discontinued and efforts be directed at the prevention of contamination of cones during transfer from storage to obturation.

A qualitative study of the causes of improper segregation of infectious waste at Nemazee Hospital, Shiraz, Iran

BACKGROUND AND OBJECTIVES Medical waste management is a major concern for healthcare facilities. One important element is the segregation of infectious waste from domestic, non-infectious waste. The aim of this qualitative study was to identify factors that negatively affect proper segregation at Nemazee Hospital, which is affiliated with Shiraz University of Medical Sciences. METHODS Study data came from focus groups involving hospital workers. Participants expressed their opinions regarding barriers to proper segregation of medical wastes. The participants gave their permission to have their comments recorded. Data analyses were based on a grounded theory approach. RESULTS The results indicated that managerial weakness was an important factor in suboptimal disposal of medical waste. It appears that hospital authorities should pay better attention to educational planning, organizational resources and supervision. Together, these considerations should help reduce waste-management errors. The results also suggest that healthcare worker training needs improvement. In general, patients and their companions, as well as the local population, did not appear to have sufficient knowledge concerning disposal of infectious medical waste. CONCLUSIONS Hospital authorities should conduct a broad review of medical waste management, including improved employee training. This step should have a positive effect on local health, as well as the environment. Improvement is also needed in the infection prevention performance of hospital healthcare workers. This approach should reduce additional production of infectious waste and costs associated with healthcare.

Disinfection of Bacterially Contaminated Hydrophilic PVS Impression Materials

PURPOSE This study evaluated disinfection of bacterially contaminated hydrophilic polyvinylsiloxane (PVS) and polyether impressions. MATERIALS AND METHODS Four light-bodied PVS (Examix, Genie, Take 1, Aquasil) and one polyether (Impregum) impression materials were evaluated using three disinfectants (EcoTru [EnviroSystems], ProSpray [Certol], and bleach [diluted 1:9]) as spray and immersion disinfections for 10-minute exposures. Pseudomonas aeruginosa ATCC 15442, Salmonella choleraesius ATCC 10708, and Staphylococcus aureus ATCC 6538 was the microbial challenge. Test specimens were prepared using aluminum molds with ten tapered cones. Mucin covered each cone, followed by 0.01 mL of each bacterium. Impressions were made using low viscosity impression material that was injected over the cones and filled custom trays. One-half of the impressions were spray disinfected, while the others underwent immersion disinfection. Trays that were contaminated but not disinfected served as positive controls, while those not bacterially contaminated or disinfected served as negative controls. The impressions were poured with Silky Rock Die Stone, and after setting, two cones were placed within a sterile capsule and triturated into powder. Four milliliters of TRIS buffer (0.05 M, pH 7.0) containing sodium thiosulfate (0.0055% w/v) were poured in each tube. After mixing, the solution was serially diluted and spread-plated onto selective agars. After incubation, colony counting occurred. RESULTS No viable bacteria transferred to casts from either spray- or immersion-disinfected impressions. Negative controls produced no microbial colonies. Positive controls produced on average 3.35 × 10(5) bacterial cells. CONCLUSION Results suggest the methods used could disinfect contaminated impression materials. Microbial transfer from nondisinfected impressions to cones approached 33.5%.

Effects of steam sterilization on the contents of sharps containers.

BACKGROUND One form of medical waste known to be capable of transmitting disease is the contaminated sharp. Safe handling and disposal of sharps is an essential element of any infection control program. Many areas allow the on-site treatment of sharps containers. However, little information currently exists as to the most effective sterilization procedures and container designs. METHODS This study was intended to evaluate the effect treatment with various autoclaves had on bacterial endospores present on strips or needled syringes. Strips contained 1.7 x 10(5) Bacillus stearothermophilus spores; syringes were soiled with equal numbers of spores or with spores plus blood. Syringes were tested capped and uncapped. A gravity-displacement autoclave and a high-vacuum autoclave were used. Strips and syringes were placed within sharps containers three quarters filled with representative materials. Six types of containers were tested. Containers were processed sitting up or on their sides. Processed strips and needles were aerobically cultured at 56 degrees C for 7 days. If sterilization was not accomplished initially, additional exposure time was added. RESULTS (1) Soiled syringes were more difficult to sterilize than strips. (2) Capping or the presence of blood did not affect sterilization efficiency. (3) Container positioning was important only for the gravity-displacement autoclave. (4) Additional exposure time was required in the gravity displacement autoclave when sterilizing soiled syringes but not strips. (5) High-vacuum autoclaving killed all spore challenges within the normal processing interval. CONCLUSIONS The data indicate that processing of sharps containers within a gravity-displacement autoclave appears to require extended exposure intervals to achieve sterilization.

Extracellular Invertase Activity from Actinomyces viscosus

Actinomyces viscosus forms dental plaque and has been implicated as a causative agent of periodontal disease and dental caries (JORDAN and KEYES, Arch Oral Biol 9: 401, 1964; JORDAN, KEYES, and BELLACK, J Periodont Res 7: 21, 1972; REGOLATI, GUGGENHEIM, and MUHLEMANN, Helv Odontol Acta 16: 84, 1972). The importance of sucrose to the development of these oral diseases has been well established. It serves as a substrate for the synthesis of plaque matrix polymers and when degraded to glucose or fructose can be fermented to organic acids that demineralize tooth enamel. A viscosus is capable of utilizing sucrose for levan synthesis by an enzyme apparently associated with the cell surface (KRICHEVSKY, HOWELL, and LIM, J Dent Res 48: 938, 1969; HOWELL and JORDAN, Arch Oral Biol 12: 571, 1967) . In the present study, the ability of A viscosus to catabolize sucrose by extracellular enzymes was determined. Actinomyces viscosus, ATCCa 15987, was cultured at 37 C for 48 hours in a complex medium (JORDAN, FITZGERALD, and BOWLER, J Dent Res 39: 116, 1960) supplemented with 2% sucrose. The cells were removed by centrifugation at 15,000 x g for 15 minutes at 4 C, and the protein was precipitated from the supernatant fluid by addition of solid ammonium sulfate to 80%0 saturation. The suspension was stirred for 30 minutes at 4 C, and the precipitate was collected by centrifugation, dissolved in water, and dialyzed against 0.05 M sodium acetate buffer (pH, 5.75) for 40 hours, with two changes of buffer. Protein concentrations were measured bv the method of Lowry et al (J Biol Chem 193: 265, 1951) . Degradation of sucrose was determined by measuring the release of reducing suirars (SoMoGYI, J Biol Chem 160: 69, 1945) and by measuring the production of free glucose

The numbers game: Sample-size determination

Sample-size determination is a crucial component of study design. Estimates of sample size are influenced by the amount of change that must occur between study groups and the degree of risk that the investigator is willing to accept in evaluating the null hypothesis. A complete understanding of the impact of sample size on the interpretation of study data is therefore a prerequisite for quality, innovative, valid research.

Effect of Water Soluble Components Derived from Cocoa on Plaque Formation

Cariostatic and antibacterial properties of cocoa and chocolate products have been reported. The presence in cocoa of tannins, theobromine, xanthine and anthocyanins has been proposed as possible causative agents (Madsen, Dietary Chemicals vs Dental Caries, Washington, Amer Chem Soc, 1970, p. 67). This study tested the effect of water soluble components of cocoa on plaque formation by Streptococcus mutans 6715. A water spluble extract of non-sweetened cocoa powdert (5% W/V) was obtained by autoclaving at 1210C for 15 min and then centrifuging the solution at 6000 rpm for 20 min. Chemical analysis revealed the presence of carbohydrate and protein: 84.06 mg/ml of total sugar (Dubois et al., Anal Chem 28:350, 1956) was obtained, and 18.22% of this sugar (15.78 mg/ml) was pentose (Brown, Arch Biochem 11:269, 1946). The anmount of protein was 89.88 mg/ml (Lowry et a ., J Biol Chenm X 93:26 5, 1 95 1). To test the effect on plaque formation, tubes containing 5 ml of complex basal medium (Jordan et al., J Dent Res 39:116, 1961) supplemented with sucrose (5% W/V), a micro-coverslip (11 x2.5 cm) and sterile cocoa extract in varying concentrations (4 tubes/concentration) were inoculated with 0.05 ml of a S. mutans culture grown for 18 hrs in CBM supplemented with 0.25% (W/V) glucose. The inoculated tubes were incubated at 370C for 18 hrs, and the coverslips were then removed, gently washed in distilled water and dried overnight in a 55°C oven. The coverslips were then placed in a fabricated specimen holder, and the light absorbances were measured at 350