ECONOMIC VALUATION OF ECOSYSTEM SERVICES: DISCUSSION AND APPLICATION

ABSTRACT

Ecosystems provide a wide range of services that improve human welfare. Changes in ecosystems imply potential changes in the generation of these ecosystem services and thus changes in welfare. In the lingo of economists, these welfare changes are measured as changes in economic values—increases in welfare being benefits and decreases in welfare being costs. For instance, individuals may benefit from, and thus value, reductions in risks to endangered species. Yet values for many changes in ecosystem services are not captured in market transactions, and thus measuring these values requires nonmarket valuation methods. This paper discusses ecosystem services and values from the viewpoint of an economist, explains what is meant by the valuation of ecosystems, and provides an overview of methods for valuation of ecosystem services. An example is presented from a recent natural resource damage assessment—the Green Bay total value equivalency study. Resources in the Lower Fox River and Green Bay in Wisconsin have been injured by polychlorinated biphenyl contamination from numerous paper mills along the river over several decades. The Green Bay study examines individuals' preferences and values for reducing ecosystem risks and improving ecosystem services and how these values are related to individuals' awareness of and use of ecosystem services in the area. The study uses methods from nonmarket valuation to scale potential restoration projects.     

ADDRESS TO THE INSTITUTE

The fire control problem deals with intensively managed softwood forest areas. The early use of the fire fighting truck in South Australia was associated with good access conditions in plantation areas. Improvement of truck performance in loose sand has been obtained by changes in gear ratio (to low gear of 8 to 1). and the size of wheels (reduced to 18 inches) and tyres (increased to 9 inches). Power pump equipment has changed from plunger pumps of low rate of delivery (5 gallons per minute) to centrifugal pumps, which are driven direct from high speed engines, and have an outlet of up to about 25 gallons pev minute.

The 4-ton truck is the standard fire fighting vehicle. This is equipped with a 500 gallon tank, power pump with outlet through two “live” reels, and a hand pump, all fixed to a steel frame. The latest power pump has a flexible performance, with a range of delivery from 2.5 to 28.8 gallons per minute, and a stream distance up to 80 feel. The assembly of this unit, loading methods and the small equipment of the truck are described.

Smaller trucks arc equipped in accordance with their capacity in the district they have to work. The water supply of the trucks depends on a system of 1,000 gallon overhead tanks, which are located at accessible and strategic places throughout the plantations. The truck tank can be filled from these at a rate of 80 gallons per minute. The gang on the truck usually consists of 8 men, each of whom has special duties.

The fire fighting truck has four main uses. These are the direct suppression of small fires, the holding of a back fire, the provision of water supplies for knapsacks, and mopping up. The scope of the equipment and the methods of its use arc described.

Possible future development of trucks and equipment and the organisation of their use are briefly outlined.     

The cancer-screening dilemma

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P REHOSPITAL U SE OF A NALGESIA FOR S USPECTED E XTREMITY F RACTURES

Introduction. Pain and its control have been studied extensively in the emergency department. Numerous studies indicate that inadequate treatment of pain is common, despite the availability of myriad analgesics. It has been suggested that oligoanesthesia is also a common practice in the prehospital setting. Objective. To assess the use of prehospital analgesia in patients with suspected extremity fracture. Methods. Emergency medical services (EMS) call reports were reviewed for all patients with suspected extremity fractures treated from June 1997 to July 1998 in a midwestern community with a population base of 223,000. Data collected included demographic information, mechanism of injury, medications given, and field treatment. Standing orders for administration of analgesia were available and permitted paramedics to give either morphine sulfate or nitrous oxide per protocol. Results. The EMS call reports were analyzed for 1,073 patients with suspected extremity fractures. The mean patient age was 47 years. Accidental injuries comprised 86.5% of those reviewed. Suspected leg fractures were most common (20%), followed by hips (18%), arms (11%), knees (10%), ankles (9%), shoulders (7.2%), hands (5.5%), and wrists (5.3%). Multiple trauma and assorted broken digits accounted for the remaining 14%. The most common mechanisms of injury were: fall (43%), motor vehicle collision (21%), and human assault (10%). Intravenous lines were placed in 9.4% of patients; 17% received ice packs; 16% received bandage/dressings; 25% received air splints; and 19% were fully immobilized. Analgesia was administered to 18 patients (1.8%): 16 patients received nitrous oxide and two received morphine. Conclusion. Administration of analgesics to prehospital patients with suspected fractures was rare. Prehospital identification and treatment of pain for patients with musculoskeletal trauma could be improved.     

Establishing biennial paramedic experience benchmarks

Objective. Since stroke symptoms are often vague, and acute therapies for stroke are more recently available, it has been hypothesized that stroke patients may not be treated with the same urgency as myocardial infarction (MI) patients by emergency medical services (EMS). To examine this hypothesis, EMS transport times were examined for both stroke and MI patients who used a paramedic-level, county-based EMS system for transportation to a single hospital during 1999. Methods. Patients were first identified by their hospital discharge diagnosis as stroke (ICD-9 430–436, n = 50) or MI (ICD-9 410, n = 55). Trip sheets with corresponding transport times were retrospectively obtained from the 911 center. A separate analysis was performed on patients identified by dispatchers with a chief complaint of stroke (n = 85) or MI (n = 372). Results. Comparing stroke and MI patients identified by ICD-9 codes, mean EMS transport times in minutes did not meaningfully differ with respect to dispatch to scene arrival time (8.3 vs 8.9, p = 0.61), scene time (19.5 vs 21.4, p = 0.23), and transport time (13.7 vs 16.2, p = 0.10). Mean total call times in minutes from dispatch to hospital arrival were similar between stroke and MI patients (41.5 vs 46.4, p = 0.22). Results were similar when comparing patients identified by dispatchers with a chief complaint indicative of stroke or MI. Conclusion. In this single county, EMS response times were not different between stroke and MI patients. Replication in other EMS settings is needed to confirm these findings.     

Pilot Study to Determine the Feasibility of Training Army National Guard Medics to Perform Focused Cardiac Ultrasonography

Abstract

Objective. To assess the ability of Army National Guard combat medics to perform a limited bedside echocardiography (BE) to determine cardiac activity after a brief training module. Methods. Twelve Army National Guard health care specialists trained to the level of emergency medical technician–basic (EMT-B) underwent an educational session consisting of a 5-minute lecture on BE followed by hands-on practical training. After the training session, each medic performed BEs, in either the subxiphoid (SX) or parasternal (PS) location at his or her discretion, on four healthy volunteers. The time required to complete the BE and the anatomic location of the examination (SX vs. PS) was documented. A 3-second video clip representing the best image was recorded for each BE. These clips were subsequently reviewed independently by two of the investigators with experience performing and interpreting BE; each BE was graded on a six-point scale designed for the study, the Cardiac Ultrasound Structural Assessment Scale (CUSAS). A score of 3 or greater was considered to be adequate to assess for the presence of cardiac activity. Where there was disagreement on the CUSAS score, the reviewers viewed the clip together and agreed on a consensus CUSAS score. We calculated the median time to completion and interquartile range (IQR) for each BE, the median CUSAS scores and IQR for examinations performed in the SX and PS locations, and kappa for agreement between the two reviewers on the CUSAS. Results. A total of 48 BEs were recorded and reviewed. Thirty-seven of 48 (77%) were obtained in the SX location, and 11 of 48 (23%) were obtained in the PS location. Forty-four of 48 (92%) were scored as a 3 or higher on the CUSAS. Median time to completion of a BE was 5.5 seconds (IQR: 3.7–10.9 seconds). The median CUSAS score in the SX location was 4 (IQR: 4–5), and the median CUSAS score in the PS location was 4 (IQR: 4–4). Weighted kappa for the CUSAS was 0.6. Conclusion. With minimal training, the vast majority of the medics in our study were able to rapidly perform a focused BE on live models that was adequate to assess for the presence of cardiac activity.     

A MBULANCE,F IRE,AND P OLICE D ISPATCH T IMES C OMPARED WITH THE A TOMIC C LOCK

Objectives. To quantify any differences between the times used by public safety answering points (PSAPs) in a multijurisdictional county compared with the atomic clock and to determine whether there was consistency in any time differences. Methods. All 25 ambulance, fire, and police PSAPs were contacted by telephone. The current time in hours, minutes, and seconds on the dispatch center's timepiece was -requested. The atomic clock time was simultaneously recorded. Time differences between the reported and atomic clock times were calculated and the absolute values were used to calculate the mean difference. The procedure was repeated one week later. Consistency in time deviation was evaluated by subtracting the time differences between weeks 1 and 2 for each center. Results. All 25 centers were contacted and three declined to participate. Time differences ranged from ?551 to 117 seconds (mean difference: 61.2 ± 120.3) for week 1 and ?103 to 79 seconds (mean difference: 36.9 ± 33.4) for week 2. Time deviations between weeks 1 and 2 were: 0 seconds for one center, 1 to 30 seconds for 12 centers, 31 to 60 seconds for four centers, and more than 60 seconds for five centers. Conclusions. The maximum time difference between dispatch center and atomic clock times was 551 seconds. This difference may be clinically significant for time-dependent research, quality improvement tasks, or medical legal reviews when multiple PSAPs are involved. Lack of consistency in time deviation over one week suggests systematic adjustment for these differences may not be possible.     

R EDUCTION OF THE C ALL -R ESPONSE I NTERVAL WITH A MBULANCE B ASE P AGING

Objective. To determine whether the call-response interval for an emergency medical services (EMS) system would be decreased through the introduction of ambulance base paging. Methods. The study community included a mixture of urban and rural areas with a total population of approximately 400,000. The EMS system is composed of two ambulance services and one central ambulance communication center with computer-aided dispatching capabilities. Approximately 30,000 calls are responded to yearly by the combined ambulance services. A before-and-after study design was used. In a retrospective review of one ambulance service, there were 224 calls collected in the period before base paging and 200 calls collected in the period after base paging was introduced. In the other ambulance service, there were 571 calls captured in the period before base paging and 515 calls captured in the period after base paging. Results. The call-receipt-to-crew-notified interval was reduced from the before period to the after period in both ambulance services: Cambridge—61.8 to 49.8 seconds (p < 0.0001); Kitchener—66.6 to 46.2 seconds (p < 0.0001). The crew-notified-to-vehicle-mobile interval was reduced from the before period to the after period in both ambulance services: Cambridge—91.8 to 73.2 seconds (p < 0.0001); Kitchener—80.4 to 66.0 seconds (p < 0.0001). Conclusions. The introduction of ambulance base paging reduced components of the call-response interval in this EMS system. Overall, the reduction in time was approximately 30 seconds, which was found to be statistically significant.     

Tourniquets: A Review of Current Use with Proposals for Expanded Prehospital Use

Objective. To perform an initial screening study of methicillin-resistant Staphylococcus aureus (MRSA) contamination in an ambulance fleet. Methods. This was a cross-sectional study of MRSA contamination in an ambulance fleet operating in the western United States in June 2006. Five specific areas within each of 21 ambulances (n = 105) were tested for MRSA contamination using dacron swabs moistened with a 0.85% sterile saline solution. These samples were then plated onto a screening media of mannitol salt agar containing 6.5% NaCl and4 mcg/mL oxacillin. Results. Thirteen samples isolated from 10 of the 21 ambulances (47.6%) in the sample group tested positive for MRSA. Conclusions. The results of this preliminary study suggest that ambulances operating in the emergency medical services (EMS) system may have a significant degree of MRSA contamination andmay represent an important reservoir in the transmission of potentially serious infections to patients.     

The Effect of Ambulance Diversions on the Development of Trauma Systems

This report examines the complex relationship between the diversion of ambulances within an emergency medical services system andthe management of trauma patients.