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Aphid (Homoptera: Aphididae) seasonal flight activity and abundance in wheat, Triticum aestivum L., and the significance of aphid species as vectors of barley yellow dwarf virus were studied over a nine-year period in the South Carolina coastal plain. Four aphid species colonized wheat in a consistent seasonal pattern. Greenbug, Schizaphis graminum (Rondani), and rice root aphid, Rhopalosiphum rufiabdominalis (Sasaki), colonized seedlingwheat immediately after crop emergence, with apterous colonies usually peaking in December or January and then declining for the remainder of the season. These two aphid species are unlikely to cause economic loss on wheat in South Carolina, thus crop managers should not have to sample for the subterranean R. rufiabdominalis colonies. Bird cherry-oat aphid, Rhopalosiphum padi (L.), was the second most abundant species and the most economically important. Rhopalosiphum padi colonies usually remained below 10/row-meter until peaking in February or March. Barley yellow dwarf incidence and wheat yield loss were significantly correlated with R. padi peak abundance and aphid-day accumulation on the crop. Based on transmission assays, R. padi was primarily responsible for vectoring the predominant virus serotype (PAV) we found in wheat. Pest management efforts should focus on sampling for and suppressing this aphid species. December planting reduced aphid-day accumulation and barley yellow dwarf incidence, but delayed planting is not a practical management option. English grain aphid, Sitobion avenae (F.), was the last species to colonize wheat each season, and the most abundant. Sitobion avenae was responsible for late-season virus transmission and caused direct yield loss by feeding on heads and flag leaves during an outbreak year.

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Anesthetic experience with three cases of the resection of glucagonoma, a rare tumor of alpha cells of pancreatic islets, is presented. Marked increases of blood glucagon and glucose levels, with the potential for clinically significant metabolic and myocardial dysfunction, did not occur during anesthesia and surgery. Associated tumors of other endocrine cell types also were absent in the three study patients. Strategies for anticipating and managing other perioperative problems associated with glucagonoma also are discussed.

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The use of fentanyl by an incremental intravenous (IV) bolus technique was evaluated in eight pediatric patients (ages 4 months to 5 years, ASA III-IV) undergoing corrective surgery for congenital heart defects. Anesthesia was induced with 5 to 10 micrograms/kg of fentanyl. Additional boluses of comparable size were given intermittently thereafter, in order that a total dose of 100 micrograms/kg was achieved just before instituting cardiopulmonary bypass (CPB). Heart rate, systolic blood pressure, various measures of anesthetic depth, and plasma fentanyl levels measured by radioimmunoassay were compared at various points during anesthesia, surgery, and recovery. Decreases in heart rate were observed at the time of sternal incision and at 30 minutes thereafter, when doses of fentanyl were near-maximal. No changes from baseline in systolic blood pressure or in anesthetic depth occurred at any of the intervals studied. The plasma concentration of fentanyl was 30 +/- 8 ng/mL just after completion of the fentanyl administration, immediately before CPB. With onset of CPB, the fentanyl level fell to 13 +/- 9 ng/mL, a statistically significant difference from the baseline value. No further change occurred over the additional 231 +/- 74 minutes in the operating room. The fentanyl concentration was 10 +/- 4 ng/mL upon entry into the recovery room. It is concluded that administration of fentanyl in small, intermittent IV boluses, with dosing completed before the onset of CPB, produces satisfactory plasma levels, anesthesia, and hemodynamic stability in children undergoing corrective surgery for congenital cardiac defects.

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A successful liver transplant program needs cooperation and communication from the surgical, blood banking, pathology, primary care, and anesthesia services. Rapid availability of laboratory data, efficient blood banking services, ability to infuse blood products rapidly, coagulation management capability, and plentiful manpower are essential.

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1. Whether joint receptors contribute demonstrably to proprioception has remained uncertain. Therefore, we tested whether an articular contribution to movement sense could be revealed if the total sensory input available to signal joint movement were reduced by eliminating movement signals from muscles. With a reduced sensory input, whatever contribution articular receptors made to proprioception ought to assume a greater-than-normal importance, and any effect of eliminating articular inputs should become more apparent. The distal interphalangeal joint of the middle finger was used, because the muscles could be decoupled from this joint by positioning the fingers to slacken the tendons. 2. To further enhance the possibility for observing an effect of eliminating articular contributions, we planned to test movement sense at positions of the joint in which the articular receptors would be most active. However, the response properties of receptors in primate finger joints were unknown, so we examined activity of receptors in finger joints of monkeys prior to testing humans. 3. Activity of receptors in interphalangeal joints of monkeys was measured over a wide range of positions before and during local anesthesia of the joint. Little response was seen over intermediate positions, but activity increased as the joint approached full flexion or full extension in much the same manner as responses previously observed with receptors in the knee, elbow, wrist, and hip joints. Local anesthetic injected into the joint space abolished the nerve activity. 4. Proprioception was tested in humans before and during local anesthesia of the joint using a movement-detection paradigm.(ABSTRACT TRUNCATED AT 250 WORDS)

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Proprioceptive ability with the proximal interphalangeal (PIP) and metacarpophalangeal (MCP) joints of the index finger in human subjects was examined using a method that could assess static-position sense independently of movement sense (Clark et al., 1985). The similarity in location and function of these joints would suggest similar proprioceptive mechanisms, but proprioceptive ability was found to be quite different for the two joints. The method of distinguishing a static-position sense from a movement sense was based on whether a subject's ability to detect a small change in joint position was impaired when the rate of rotation was progressively reduced. An awareness of static-position should not depend on the rate at which a joint is placed into position. However, if subjects use movement signals to detect changes in joint position, slowing the rate of displacement should reduce the intensity of these signals and make the displacements more difficult to detect. This method indicated a static-position sense with the MCP joint but only a movement sense with the PIP joint. It was confirmed that sensory input from regions of skin not stretched or deformed by rotation of the joint can influence proprioceptive sensibility with the fingers. Anaesthesia of the tip of the index finger or of the thumb blunted subject's perceptions of movement of the PIP joint of the index finger. However, anaesthesia of the PIP joint itself had no observable effect on the ability to sense movement of the joint.

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Twenty-six consecutive pediatric patients undergoing reparative procedures necessitating cardiopulmonary bypass were prospectively studied to determine changes in serum levels of 6-keto-prostaglandin F1 alpha and thromboxane B2. Cardiac lesions included acyanotic lesions (five patients), obstructive lesions (10 patients), and right-to-left shunts (11 patients). There was a significant (p less than 0.05) increase in 6-keto-prostaglandin F1 alpha from preoperative levels measured at the time of arterial and venous cannula insertion. This concentration was maintained throughout cardiopulmonary bypass and remained significantly elevated (p less than 0.001) in the recovery room, but returned to preoperative levels by the morning after the operation. Preoperative levels of thromboxane B2 varied widely and were not significantly different from intraoperative levels. The postoperative levels of thromboxane B2, however, were significantly different (p less than 0.05) from the intraoperative levels. In the pediatric age group undergoing cardiopulmonary bypass, 6-keto-prostaglandin F1 alpha and thromboxane B2 change during bypass but do not significantly differ when preoperative levels are compared to postoperative values.

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We studied proprioception with the ankle joint and the metacarpophalangeal (MCP) joint of the index finger of humans by use of a method that could distinguish a position sense from a movement sense. The test measured how subjects' ability to detect a fixed displacement of a joint varied with the rate of joint rotation. A position sense should not depend on the speed of joint placement; therefore slow rates of movement should not degrade subjects' ability to sense joint displacements. However, in the absence of a position sense, subjects would presumably rely on movement signals that do depend on the rate of rotation, and their ability to detect displacements should decrease when rate decreases. Subjects could sense small displacements of the ankle (+/- 3.5 degrees) and the MCP joint (+/- 2.5 degrees lateral excursions) with no decrement in performance at speeds as low as 0.25 degrees/min for the ankle and 0.5 degrees/min for the MCP joint (the slowest tested thus far). The findings confirm the existence of a position sense with these joints. Block of the ulnar nerve at the wrist, which paralyzes the interosseous muscles that adduct and abduct the MCP joint but presumably leaves skin and joint mechanisms unaffected, substantially impaired subjects' ability to detect the lateral excursions at slow speeds. Performance fell sharply at speeds less than 128 degrees/min and leveled off at approximately 20% detections at speeds less than 4 degrees/min. Increasing displacement to +/- 7 degrees did not improve performance. Block of the common peroneal nerve at the knee, which paralyzes the ankle dorsiflexor muscles, substantially impaired subjects' ability to detect the +/- 3.5 degrees displacements at slow speeds when the foot was positioned to slacken the plantarflexion muscles (which were not affected by the block). Performance fell sharply at speeds less than 256 degrees/min and approached zero at speeds less than 16 degrees/min. However, positioning the foot to stretch the plantarflexor muscles restored subjects' performance to near normal. Local anesthetic injected into the MCP joint space produced no observable effect on the ability to detect either slow or fast excursions. The joint anesthesia went unnoticed by the subject. We conclude that independent and separable senses exist for limb position and limb movement and that normal position sense requires sensory inputs from the muscles.

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Patients receiving parenteral nutrition support frequently undergo operative procedures. Proper selection of patients and close monitoring of glucose levels are crucial if parenteral nutrition is to be maintained intraoperatively. The Dextrometer was used in 10 patients receiving parenteral nutrition intraoperatively. The difference between the Dextrometer readings and the serum glucose level obtained by laboratory analysis was less than 10% in 83% of cases and readings were most accurate in the 200 to 400 mg/dl range. The Dextrometer provides a simple, inexpensive, and reasonably accurate method of monitoring glucose intraoperatively as part of the optimal management of these patients.

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Intrapartum maternal temperatures and neonatal temperature immediately after birth were measured in 50 cases. Maternal temperatures were determined in part by the amount of hyperventilation, perspiration, and physical activity, with those who were calm and less active having the higher temperatures. Thus, with hyperventilating parturients, it was difficult to define "normal" maternal temperatures. The neonatal rectal temperature immediately after birth seemed best correlated with the maternal vaginal temperature. Two examples are presented which suggest that cases of fetal distress associated with tachycardia and decreased placental exchange may be examples of isolated fetal hyperthermia.

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PIP: The article describes the case of a 38-year-old woman on whom laparoscopic tubal ligation was performed on an outpatient basis. During the procedure a 14 mm. tear was caused in the aorta, possibly by the Verres needle or the laparoscopic trocar, with subsequent hemorrhage and cardiac arrest. Similar cases are rarely reported in the literature. Still, it is important that facilities for massive transfusion should be available even in outpatient clinics.^ieng

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