Biomedical subjects

R L Olson

Publications and source records attributed to R L Olson.

At least 19 recordsLinked to original sources

PubMed2001

The addition of interscalene block to general anesthesia for patients undergoing open shoulder procedures.

Several studies have demonstrated that interscalene brachial plexus anesthesia alone decreases postoperative pain, nausea, vomiting, urinary retention, and unplanned hospital admissions compared with general anesthesia alone. Anecdotal evidence suggests that an interscalene block combined with general anesthesia decreases unwanted effects of general anesthesia following open shoulder surgery. We compared the effect of combined interscalene block and general anesthesia with general anesthesia alone on Aldrete scores, length of postanesthesia care unit (PACU) stay, verbal rating scale (VRS) pain scores, incidence of postoperative narcotic administration and nausea, and patient satisfaction in a convenience sample of 52 men and women, ASA physical status I, II, or III. Group 1 received standard general anesthesia alone. Group 2 received an interscalene block in combination with general anesthesia using a standard technique. Group 2 had significantly lower VRS scores than group 1 while in the PACU, on the day of surgery, and on postoperative days 1 and 2. Overall satisfaction with the anesthetic technique was higher in the group 2 than in group 1. Results suggest that adding an interscalene block to general anesthesia can be of value in today's outpatient-dominated surgery schedule.

Adult↗

PubMed1999

Quantification of insensible water loss associated with insufflation of nonhumidified CO2 in patients undergoing laparoscopic surgery.

A growing number of surgical procedures of increased duration are being performed using laparoscopic techniques. No study to date has quantitated the potential insensible water loss associated with laparoscopic surgical procedures as a result of intra-abdominal humidification of insufflated nonhumidified CO2 gas. The purpose of this study was to quantitate this insensible water loss by measuring the CO2 gas volume consumed and the relative humidity of the vented gas. Ten patients presenting for elective procedures were enrolled in this descriptive prospective IRB-approved study. After secondary trocar placement and attainment of the desired intra-abdominal pressure, vented laparoscopic gas was passed directly through a dewpoint monitor sensor. Determinations of dewpoint and gas temperature were made immediately after the start of the surgical procedure and every 15 minutes thereafter until completion. Dew-point temperature was converted to relative humidity, which was used to determine the water vapor content of the gas. The actual water content (absolute humidity) of the vented laparoscopic gas was then calculated from the water vapor volume. The mean relative humidity of the vented laparoscopic gas was 92.2% +/- 0.8%. The mean laparoscopic gas flow rate was 42.0 +/- 5.0 L/h. The mean volume of water (absolute humidity) loss attributed to humidification of dry CO2 was found to be less than 1 mL/h. Insufflation of dry CO2 during laparoscopic procedures therefore results in insignificant insensible water loss.

Adult↗

PubMed1989

Plant responses to elevational gradients of O(3) exposures in Virginia.

In Shenandoah National Park, O(3) monitoring data were characterized and attempts were made to relate O(3) concentration levels to visible foliar injury observed for five plant species surveyed. Foliar injury for three species increased with elevation. The 24-h monthly mean O(3) concentrations tended to increase with elevation; however, the number of elevated hourly occurrences did not. Although the frequency of high hourly O(3) concentrations did not consistently increase with elevation, O(3) exposures in the park may have been high enough to provoke an effect that may have been enhanced by vegetation sensitivities that differed as a function of altitude.

Journal Article↗

PubMed1988

CELSS for advanced manned mission.

An overview of the major concepts of Controlled Ecological Life Support System (CELSS) includes an identification of environmental factors, such as gravity levels, light levels, and growth volume, that influence the type of CELSS system that can be developed. Various plant growth systems are described together with their possible space applications. Life support functions performed by plants include food production, atmosphere regeneration, and water purification. Selected relationships between biological and physical-chemical life support techniques are considered as a part of these functions. Consumers in a CELSS may be humans, animals, or microorganisms, but nutritional, water, and atmosphere requirements of humans are emphasized in this report, as they are the primary requirement drivers for a CELSS design. The human role in waste generation is discussed as it affects plant nutrient availability. The role of waste management systems in recovering nutrients for plant growth and requirements for CELSS are defined for air, water, and food. Both physical and a biological nutrient recovery/waste disposal systems are examined. The separate subsystems of a CELSS are identified and discussed. Nutrient recovery, plant irradiation, automation, and facilities equipment and applications are reviewed with special attention to direct solar irradiation using fiber optics. These subsystems, along with other environmental control systems, such as thermal, humidity, and ventilation, are essential to plant growth in the space environment.

Crops, Agricultural↗

PubMed1984

CELSS transportation analysis.

Regenerative life support systems based on the use of biological material have been considered for inclusion in manned spacecraft since the early days of the United States space program. These biological life support systems are currently being developed by NASA in the Controlled Ecological Life Support Systems (CELSS) program. Because of the progress being achieved in the CELSS program, it is time to determine which space missions may profit from use of the developing technology. This paper presents the results of a study that was conducted to estimate where potential transportation cost savings could be anticipated by using CELSS technology for selected future manned space missions. Six representative missions were selected for study from those included in NASA planning studies. The selected mission ranged from a low Earth orbit mission to those associated with asteroids and a Mars sortie. The crew sizes considered varied from four persons to five thousand. Other study parameters included mission duration and life support closure percentages, with the latter ranging from complete resupply of consumable life support materials to 97% closure of the life support system. The paper present the analytical study approach and describes the missions and systems considered, together with the benefits derived from CELSS when applicable.

Cost-Benefit Analysis↗

PubMed1975

Epidermal apoptosis: cell deletion by phagocytosis.

Apoptosis is a process found in many tissues by which devitalized cells are eliminated in an orderly manner. In skin, apoptosis occurs following sunburn, in Bowen's disease and in basal cell carcinoma. Scattered cells are observed in which the cytoplasm has become condensed and dyskeratotic. These dyskeratotic cells are phagocytized, either in toto or in fragments by surrounding keratinocytes. This process involves the condensation, fragmentation, phagocytosis and digestion of individually degenerated cells. The mass of a tissue is thus related to the balance between cell formation (mitosis) and cell destruction (apoptosis). In epidermal and other surface tissues, the rate of exfoliation must also be considered.

Bowen's Disease↗

PubMed1975