S12 INTRODUCTION: A number of causal factors have been described in the etiology of postoperative nausea and vomiting (PONV). PONV. is not only unpleasant and uncomfortable but delays discharge. [1] The actual incidence of PONV and the method of treatment varies widely amongst institutions and patient populations. [2] A number of different modalities and treatments have been proposed to prevent and treat PONV. The modalities with the least side effects are often newer and the most expensive, while the least expensive modalities often have bothersome side effects. Furthermore, most studies designed to study the efficacy of antiemetic agents used to treat or prevent PONV have been protocol driven and compared to placebo in selected patient populations. Yet, real patients are diverse and their care is individualized and not usually protocol driven. Thus, current studies evaluating different antiemetics often do not reflect the way they are most commonly used in clinical practice. PONV was felt to be a problem at our institution contributing to prolonged PACU stay i.e., greater than two hours. Furthermore, the overall incidence of PONV at our and other major teaching institutions was not known. To evaluate the efficacy of different methods of intraoperative antiemetic prophylaxis on the incidence of PONV, we designed a prospective study. METHODS: A 34 item continuous quality assurance (QA) document was modified to 1) identify intraoperative antiemetics, 2) determine the incidence of PONV, and 3) capture current practice patterns of an anes practice in a large Midwestern university hospital. Demographic data, anesthetic risk factors, and surgical procedures were collected to evaluate causal factors for PONV. The antiemetics commonly used to provide intraoperative prophylaxis for PONV (droperidol, metoclopramide, ondansetron, and propofol maintenance) during general anesthesia were listed. A scale was developed to classify the intensity of PONV in the Post Anesthesia Care Unit (PACU) or Ambulatory Surgery Unit (ASU) on a 10 point Visual Analogue Nausea Scale (VANS) (0=no nausea, 10=excruciating nausea). The anes dept and PACU nurses were educated regarding the new categories on the QA form via an inservice. They were instructed to complete the OR, PACU and ASU events on the QA form as they had in the past. No changes in anesthetic practice were requested or implemented. The data was compiled for three months and are presented in a descriptive fashion. RESULTS: A QA form was available for 4,606 patients during the 3 month study period. Fifty-five percent of the patients were same day admissions (ADP), 15% were inpatients (IP) and 30% were outpatients (OP). Although females accounted for 51 % of the study population they experienced more PONV than males (64 % vs. 35 %). Patients comprised all ASA classes and no differences were found between the groups. The overall incidence of PONV was 7.1%. Table I reveals the incidence of PONV by admission type. Table II demonstrates the incidence of PONV when a prophylactic intraoperative antiemetic was indicated on the QA form as being administered. The overall incidence of nausea when an intraoperative antiemetic was administered was 5.7%.Table I: Incidence Of PONV by Admission Type and LocationTable II: PACU Incidence of PONV by Intraoperative ProphylacticDISCUSSION: The incidence of nausea was greatest in OP while in the PACU. The incidence of vomiting was greatest in the IP followed by OP during their stay in the PACU. It was interesting to note that the rate of nausea was much less than vomiting. Our data suggests that the use of more expensive agents e.g., ondansetron or propofol, was not more effective than the least expensive agents e.g., droperidol or metoclopramide when used prophylactically. These preliminary data suggest that droperidol and metoclopramide are an effective method of providing prophylaxis against PONV and may also be cost effective. Further QA studies are necessary to evaluate and develop clinical practice guidelines for implementing changes to decrease PONV at a lower cost.

Measureable levels of chlorpyrifos were seen in air and on horizontal and vertical surfaces over an 84-day sampling period following application by two different methods. Pressurized aerosol applications had the highest airborne levels over the 84-day sampling period, and movement into adjacent, nontreated rooms was seen 7 days after application. Highest surface residues found were located at floor/wall interfaces and were due probably as a result of splash or overspray around treated areas. Residue levels from desk sides were very low and all surface residues were highly variable. One could not predict what surface levels would be based upon airborne concentrations.

Methods were developed to detect cyfluthrin in ambient air and on surfaces following its application to control pests. A variety of adsorbent media (Tenax GC, Orbo 42, polyurethane foam [PUF], fiberglass filter paper [FFP], GN-4 membrane filter and Chromosorb 102) were tested to determine the most efficient medium for trapping cyfluthrin from ambient air. Fiberglass filters were selected based on a trapping efficiency of 89% at a sensitivity of 0.5 mu g. Surface samples were taken from stainless steel plates with a cotton ball soaked in n-hexane. Recoveries averaged 99% at a sensitivity of 0.01 mu g/cm(2). The methodology was tested in empty dormitory rooms following crack and crevice applications of three different commercial formulations of cyfluthrin. No detectable cyfluthrin was found in air samples through 14 days. Cyfluthrin was detected in two surface samples up to 3 days post treatment.

Abamectin was applied into or near cracks and crevices with a Whitmire flowable dust applicator. Other forumulations were applied from self-pressurized, aerosol-type containers as pin-stream sprays into cracks and crevices. Single-family dwellings, located in Edgecombe or Lenoir counties, NC, served as test sites. Five kitchens with a minimum of 100 living German cockroaches sighted during a preliminary visual survey were assigned to each formulation. Preapplication visual tallies of living cockroaches in kitchens compared to tallies at specified intervals after treatment indicated efficacy. Insecticide reapplications were made in kitchens where any living cockroaches were observed during postapplication tallies. Non-test rooms in the dwellings were treated as needed at each visit to minimize movement of German cockroaches into treated areas. The amount of insecticide applied during the initial application and reapplications and the size, temperature, and relative humidity of the kitchens, were recorded. Analyses were based on % reduction of cockroaches (pre- versus post-treatment tallies for a kitchen). Since the area of each kitchen floor and wall space varied the active ingredient applied per kitchen was converted to a 50 m2 basis for comparative purposes. The active ingredient applied in the initial applications for all formulations ranged from 0.1 to 6.2 g and from 0.0 to 1.7 g for the reapplications, respectively. Smaller quantities of insecticide were used for the reapplications because partical cockroach control usually resulted from the initial applications.

Insect growth regulators are synthetic chemicals that mimic the function of hormones that occur naturally in arthropods. Two such insect growth regulators, methoprene and hydroprene, were tested to determine effects on growth of laboratory populations of the American house dust mite, Dermatophagoides farinae Hughes. Adults and immature mites were treated with four concentrations of each chemical in contact and diet-incorporation bioassays. Data were collected after 30 and 90 d of exposure to the treatments. Both compounds significantly suppressed population growth when compared with acetone controls at concentrations of > or = 5%. Methoprene was more effective than hydroprene in diet-incorporation bioassays and was slightly more effective for the first 30 d of the contact assays. A second set of contact and diet-incorporation assays was done using one concentration (7.5%) of methoprene and hydroprene to determine the effect of these compounds on population dynamics of D. farinae. In this experiment, population numbers were evaluated at weekly intervals for 13 wk. The average number of mites in the untreated control population increased by more than 10 times the original inoculum during the experiment while the number of mites in the treated containers did not increase significantly. This trend was similar for both contact and diet-incorporation bioassays although the average number of mites per container was significantly higher when the treatments were incorporated in the house dust mite diet than when applied directly to the substrate.

Various self-pressurized sprays, supplied by Whitmire Research Laboratories (St. Louis, MO), were directed into cracks and crevices in kitchens within single-family dwellings located in Duplin, Johnston and Sampson counties, NC. Kitchens with a minimum of 100 German cockroaches sighted in a preliminary survey served as individual plots with 5 replications per treatment. Preapplication visual tallies in kitchens compared to tallies at specified intervals after treatment indicated efficacy. The amount of insecticide applied and the size, temperature and relative humidity of the kitchens were recorded. When living cockroaches were observed during the reinspection intervals additional insecticide applications were made to the infested areas. Other rooms in the dwellings were treated as needed at each application time to minimize immigration of German cockroaches. Cockroach tallies were not made in these rooms nor was insecticide volume recorded. The active ingredient applied initially and during reapplications for all formulations ranged from 0.01-4.9 g and 0-3.0 g, respectively, per 50 m2 of kitchen floor and wall surfaces. Smaller quantities of insecticide were used for reapplications because partial cockroach control resulted from the initial applications.

The last twenty years have seen an increased awareness of insecticide residues in air, food and on surfaces within structures following treatments for control of indoor pests. Studies conducted at North Carolina State University have focused on determining the environmental fate of pesticide residues in air, food, soil and on surfaces following controlled or monitored applications. The objectives of these studies were: 1) to determine methodologies to quantitate residues in air and on surfaces; 2) to follow the movement of insecticides in air and on target and non-target sites; 3) to quantitate residue levels in pest control offices, warehouses, vehicles and on personnel; and 4) to quantitate residue levels of termicides in air and soils of homes following application. These data will be summarized in this chapter.

Pin-stream sprays from self-pressurized, aerosoltype containers, were directed into cracks and crevices of dwellings. Single-family dwellings, located in Sampson or Duplin counties, NC, served as test sites. Kitchens with a minimum of 100 living German cockroaches sighted in a preliminary survey were used, with 5 replications. Preapplication visual tallies of living cockroaches in the kitchens compared to tallies at specified intervals after treatment indicated efficacy. The chlorpyrifos formulations were continued through 24 wk in order to compare the efficiencies of chlorpyrifos with and without fenoxycarb. The amount of insecticide applied and the size, temperature and relative humidity of the kitchens, were recorded. Insecticide reapplications were made in kitchens where living cockroaches were observed during post application tallies. Non-test rooms in the dwellings were treated as needed at each visit to minimize migration of German cockroaches. Analysis were calculated on percent reduction of cockroaches (pre- versus post-tallies for a kitchen). The active ingredient applied in the initial applications for all formulations ranged from 0.12 to 5.3 g and 0.0 to 1.6 g during reapplications, respectively, for 50 m2 of kitchen floor and wall surfaces.

A study was conducted to compare the efficiency of five adsorbents used by government and private laboratories to collect airborne pesticides. Six pesticides, acephate, chlordane, chlorpyrifos, diazinon, heptachlor, and propoxur, were vaporized in a closed system and collected on each of the adsorbents, Chromosorb 102, ORBO 42, ORBO 44 (chlordane and heptachlor only), polyurethane foam (PUF) or Tenax GC, by drawing 250 L of air through the adsorbent. There were no differences in collection efficiency of the five pesticides on Chromosorb 102, ORBO's 42/44, and PUF. The efficiency with Tenax was somewhat less with several of the pesticides.

Self-pressurized sprays were directed into cracks and crevices of dwellings using appropriate crack and crevice equipment. Microencapsulated chlorpyrifos was applied as a pinstream spot application from a 3.785 liter compressed air sprayer directed towards cracks and crevices. Abamectin was applied into or near cracks and crevices with a hand-type duster. Single-family dwellings, located in Wake, Harnett or Cumberland counties, NC, served as test sites. Kitchens with a minimum of 25 living German cockroaches sighted in a preliminary survey were used, with 5 replications. Preapplication visual tallies of living cockroaches in the kitchens compared to tallies at specified intervals after treatment indicated the efficacy. The amount of insecticide applied and the size, temperature, relative humidity, and sanitation condition of the kitchens, were recorded. Additional insecticide applications were made, with the amount recorded, when living cockroaches were observed during specified reinspection visits, except in 5 kitchens treated with microencapsulated chlorpyrifos. These kitchens did not have any additional insecticide applied in order to determine the efficacy of one application. Other non-test rooms in the dwellings were treated as needed at each visit to minimize migration of German cockroaches. Analyses were calculated on percent reduction of cockroaches (pre- versus post-tallies for a kitchen).

Field tests were conducted to determine he relative efficiency of Baythroid compared to Orthene, which has a wasp control label, for single-comb wasp reduction. Adults of Polistes sp. resting on rests attached to buildings were tallied. Nests were sprayed with a 0.25% Baythroid self-pressurized spray or a 1.0% Orthene PCO concentrate (20 replications each). The Orthene was applied at 20 psi using a coarse fan spray from a 3.8-liter compressed-air sprayer. Both sprays were applied randomly to nests for 2-3 s from a distance 2.5 to 3 ft between 6:15 and 10:30 A.M. on Aug 23. Five nests were used as untreated checks. Evaluation of insecticide efficacy and residual life was accomplished by comparing the percent wasp reduction on nests over time. Posttreatment counts were taken at intervals of 8 h and 1, 3, 7, 14, 21, and 28 days.

Field tests were conducted to determine the relative effectiveness of self-pressurized sprays containing 1 of 2 concentrations of cyfluthrin or 1 concentration of an avermectins bait or dusttype baits of avermectins, boric acid, or fenoxycarb. MaxForce™ (hydramethylnon) bait and a self-pressurized spray of 0.5% chlorpyrifos, both labeled for cockroach control, were used as standards. Dry baits were applied with a Getz™ or Controlbulb™ duster. MaxForce was used as sold to homeowners; the self-pressurized formulations were applied as supplied by Whitmire Research Laboratories, St. Louis, Mo. All formulations were applied to cracks and crevices, except the MaxForce bait stations, which were attached to kitchen surfaces as directed by the label. Single-family houses located in Sampson County, N.C., served as test sites. Only houses with a minimum of 25 cockroaches sighted in a preliminary survey of the kitchen were used. Visual counts in the kitchen before the initial application and at specified intervals afterward determined the percent reduction in cockroach populations. The amount of insecticide for kitchen applications was recorded. No additional MaxForce stations were placed in the MaxForce test houses after the initial application. Other rooms in all test houses were treated, but cockroach numbers and amount of insecticide applied were not measured. Each formulation was replicated 5 times. Analyses were calculated on percent reduction of cockroaches (pre- versus postcounts for a house) using a general linear models procedure and the Goodnight [1982] Waller-Duncan K-ratio t test for variables. The combined wall and floor surfaces in the kitchens ranged from 35 to 90 m2 with a mean of 55 m2. The active ingredient applied in the initial application and during reapplications ranged from 0.007 to 4.2 g and from 0.0 to 1.4 g, respectively, for 50 m2 of kitchen floor and wall surfaces. Smaller quantities of insecticide were used for the reapplications because partial cockroach control had resulted in most of the dwellings.

A 10% solution of DDVP was sprayed until a total volume of 20.9 liters of the solution had been released into the air in a tobacco-storage warehouse. Air samples were taken at various times after application in three different experiments to measure DDVP levels with time and to determine if DDVP concentrations exceeded the threshold limit (TVL). In the three experiments, residue levels were highest initially in the center of the warehouse compared to a corner, but residue levels tended to equalize over the sampling period. The data indicated that workers entering storage warehouses after application of DDVP would not encounter hazardous levels of this material.

Known amounts of acephate, chlorpyrifos, and diazinon were applied to Formica, unfinished plywood, stainless steel, and vinyl tile. Cotton-ball and dental wick materials were dipped in 2-propanol and "swiped" over the treated surface area two time. More acephate was found on the second swipe compared to the first from vinyl tile, similar amounts on both swipes from plywood, and less on the second swipe from formica and stainless steel. The ratio of chlorpyrifos on Swipe 1 compared to Swipe 2 found with cotton-ball on both formica and stainless steel surfaces was equivalent (6:1), but a considerable difference was seen when two dental wick swipes were used. Residues of diazinon removed from formica and stainless steel were equivalent, regardless of the swiping material used. Residues of chlorpyrifos were detected by taking swipes of surfaces in two restaurants and a supermarket up to 6 mo after a prescribed application by a commercial pest control firm. The data show that measurable amounts of chloropyrifos can be detected on surfaces not treated with the insecticide for at least 6 mo.