Spontaneous rupture of a true uterine artery aneurysm: a cause of retroperitoneal haematoma.

We report the first case of spontaneous rupture of a true uterine artery aneurysm in a 69-year-old woman presenting with severe abdominal pain, a left iliac fossa mass, anaemia and a retroperitoneal haematoma on CT scanning. In this patient, the aneurysm was successfully embolised using microcoils. The different imaging modalities used for diagnosis and the treatment options are discussed.

Accuracy and precision of computer models to predict passage of crude protein and amino acids to the duodenum of lactating cows.

To evaluate the ability of several models to accurately and precisely predict the passage of crude protein (CP) and amino acids to the duodenum of lactating cows, we simulated data from six published studies using the 1989 National Research Council equations, the Mepron Dairy Ration Evaluator (version 1.1), the University of Pennsylvania release of the Net Carbohydrate and Protein System (version 2.12p), the Cornell Net Carbohydrate and Protein System (version 3), and CPM Dairy (version 1.0). Models overestimated the passage of CP from microbes by an average of 323 g/d, and underestimated the passage of CP from feed by an average of 874 g/d. These two errors were partially canceled when CP from microbes and feed were summed to estimate passage of total CP to the duodenum. Many dietary composition variables appeared to bias the predictions; however, the influence of any one variable was small. The efficiency of modeling was high for most predictions but was variable for predicting passage of specific individual amino acids to the small intestine depending on the model selected. These simulations indicated no obvious advantage for any model over the others tested. The models responded to changes in diets by altering the amount of protein from microbes and feed that reached the duodenum, resulting in improved accuracy of predictions of duodenal CP passage compared with simply assuming a constant value for passage of CP to the duodenum.

Prediction of crude protein and amino acid passage to the duodenum of lactating cows by models compared with in vivo data.

To determine whether statistical inferences obtained from predictions by models were similar to those of measured data from individual cows, data from six research trials published between 1989 and 1997 were simulated using the 1989 National Research Council Model, the Mepron Dairy Ration Evaluator (version 1.1), The University of Pennsylvania release of the Net Carbohydrate and Protein System (version 2.12p), The Cornell Net Carbohydrate and Protein System (version 3), and the CPM Dairy (version 1.0). Both predicted and measured protein fractions were analyzed by ANOVA and compared to determine whether statistical inferences among treatments from predictions by the models were similar to those from the measured data. The interpretations and statistical inferences of measured data did not always agree with those for predicted data. All models responded to changes in diet composition and often predicted that dietary changes would result in statistically different amounts of protein and amino acids passing to the duodenum than were observed in the measured data. The direction of predicted change among treatments for passage of nitrogen fractions to the duodenum also did not agree with the measured data a large percentage of the time. Discrepancies in ANOVA and interpretations between predicted and measured data may be due to the reduction in variation associated with modeling biological systems, associative effects of feeds not accounted for by models, inadequate equations in the models, inadequate description of feeds, or experimental error in measured data. Before model simulations of duodenal flow of crude protein and amino acids can be substituted for experimental measurements, better descriptors of main dietary effects, microbial protein production, ruminal protein degradation, and interactions among dietary factors must be developed.

Contribution of heating, ventilation, and air conditioning airflow and conversation to the ambient sound in a neonatal intensive care unit.

Sound reduction strategies in the neonatal intensive care unit (NICU) must focus on the sources of excessive sound. We studied the relative contribution of personnel conversation and heating, ventilation, and air conditioning (HVAC) airflow by measuring several parameters of sound during four environmental conditions: unaltered ambient sound, HVAC airflow off, HVAC airflow and conversation off, and conversation off. All measurements were decreased by interrupting HVAC airflow and conversation. The reduction was greater when conversation was stopped. The method of sound reduction did not change the frequency distribution of sound. Attention to personnel conversation may be effective in lowering sound exposure in the NICU. The contribution of HVAC airflow should be measured in new constructions and renovations.

Sound transmission into incubators in the neonatal intensive care unit.

OBJECTIVE: To measure the attenuation of sound by modern incubators. STUDY DESIGN: LEQ, LMAX, LPEAK, and frequency distribution were measured simultaneously inside and outside two recent model incubators. RESULTS: The attenuation of sound (outside minus inside) was 15 to 18 dBA with the motor off and 4 to 8 dBA with the motor on. There was a significant difference between incubators in their attenuation of sound. Octave band analysis showed attenuation in frequency bands of > 31.5 Hz with the motor off. With the motor on, the sound level inside the incubator was higher than outside at frequency bands of < 250 Hz. CONCLUSION: Caring for infants inside modern incubators reduces "averaged" sound exposure to levels near those recommended for the neonatal intensive care unit. Lower frequency sounds are louder inside the incubator and arise from the incubator motor.

Peak noise distribution in the neonatal intensive care nursery.

OBJECTIVE: To measure short duration sounds (L(PEAK)) in the neonatal intensive care unit and describe their intensity, incidence, and periodicity in relationship to activities within the unit. STUDY DESIGN: We measured 1-minute L(PEAK) at four locations within the intensive care unit, accumulating 48 hours of data for each weekday. RESULTS: Thirty-one percent of the L(PEAK) exceeded 90 dB. For further analysis, the data were transformed to the proportion exceeding 90 dB. These values varied significantly with day, week, location, and time of day. During physician rounds, there was a 16% relative increase in L(PEAK). CONCLUSION: These data demonstrate the intensity, incidence, and periodicity of short duration sounds in the intensive care nursery. Short duration sounds are known to affect the infant's physiological and behavioral states and should be addressed in future recommendations for sound control and reduction strategies.

Establishing a noise measurement protocol for neonatal intensive care units.

OBJECTIVES: To compare three noise exposure measurement methods and determine the effect of location within the nursery, time of day, day of week, shift, and activities such as nursing shift change and physicians' rounds on noise measurements. STUDY DESIGN: We performed a noise distribution survey, central site measurements, and quadrant area measurements in our nursery. The measurements made were sound pressure level and hourly LEQ, LMAX, and L10. RESULTS: The noise distribution survey method was least useful because steady-state noise sources were the exception. Differences between central site and quadrant area measurements were minimal. There was no significant effect of time of day, shift change, or physician rounds on the noise measurements. CONCLUSIONS: In an open nursery with excessive noise levels central site measurements over a relatively short time accurately reflect the noise exposure. A protocol for measuring noise exposure in the neonatal intensive care unit is appended.

Does ibuprofen affect bilirubin-albumin binding in newborn infant serum?

Intravenous ibuprofen is being studied in sick, premature infants for the prevention of intraventricular haemorrhage and closure of the ductus arteriosus. We tested the effect of ibuprofen on bilirubin-albumin binding in adult and newborn infant serum by measuring the free ibuprofen concentration in the presence of bilirubin (reverse displacement method). At clinically appropriate ibuprofen concentrations the free fraction of bilirubin is increased by a factor of 4. Ibuprofen may increase the risk of bilirubin encephalopathy when used in sick, premature infants.

The role of industry in international animal agriculture.

The role of agribusiness and the linkages needed with other organizations and governments to be effective in developing countries are examined. After these links are established, then the strengths of business (organizing knowledge, capital, and people into productive and profitable enterprises) can contribute to improved agricultural productivity in developing countries. Technologies and products already transferred and examples of future products of biotechnology (bovine somatotropin to increase milk production and virus-resistant sweet potatoes) are discussed. Higher input systems can be successful in developing countries, as exemplified by the Saskawa-Global 2000 project, which had doubled crop yields of small-holders in some of the poorest countries of West Africa. Combining the forces of U.S. agriculture and its related agribusiness and the new products of biotechnology, the United States has an opportunity to provide the leadership in both a moral and material way to ensure there is sufficient food for all people as we move into the third millennium.

The cardiopulmonary system and movement dysfunction.

Physical therapy primarily involves the identification and treatment of problems related to movement. Movement dysfunction usually is attributed to impairments of the neuromuscular and musculoskeletal systems. The cardiopulmonary system plays an important role in movement because of its function of transporting oxygen to skeletal muscle. Abnormalities of the cardiovascular and pulmonary systems can produce limitations in physical function. The purposes of this article are to describe the steps involved in the transfer of oxygen from atmospheric air to skeletal muscles and to provide examples of problems that can occur with each step of the process. Common signs and symptoms of potential problems involving the cardiovascular and pulmonary systems also will be discussed.

Effects of cardiovascular medications on exercise responses.

Many patients who are referred for physical therapy take medications that affect either their physiological responses to exercise or their ability to exercise. The purpose of this article is to discuss how medications potentially can affect cardiovascular responses to exercise. The effects of selected medications on heart rate, blood pressure, and electrocardiographic responses during exercise; on exercise performance; and on training adaptations are discussed. The types of medications included in this review are beta-adrenergic receptor antagonists, vasodilators, diuretics, digitalis, and antiarrhythmic agents. The mechanisms of action and the clinical indications are described for each category of drugs. Ways in which each of the categories of drugs interacts with exercise responses, exercise performance, and training adaptations are described. Knowledge of a person's medications can provide valuable information on current physical condition and medical history and can alert therapists as to how exercise responses may be altered. Potential complications that are likely to occur during exercise can be identified, facilitating the design of safe and effective treatment programs.

Pressure ulcer prophylaxis in elderly patients using polyurethane foam or Jay wheelchair cushions.

A significantly lower proportion of the patients in the Jay group (25%) experienced pressure ulcer formation during the three months of observation as compared to the foam group (41%). No statistically significant differences were found between groups on the location, severity, or healing duration of the pressure ulcers. Most lesions (65%) were limited to persistent erythema of intact skin, and healed in three to four weeks. Significantly higher proportions of patients in the Jay groups (7%) rejected their cushion because of discomfort as compared to foam (1%). The incidence of pressure ulcers was significantly higher among those patients who experienced peak interface pressures recorded at 60 mmHg or higher, had low Norton scores (< or = 11), or were malnourished.

Oxygen consumption using the K2 telemetry system and a metabolic cart.

The purpose of this study was to compare measurements of oxygen consumption (VO2), ventilation (VE), and respiratory rate (RR) between a relatively new portable, telemetry system (K2) and a system that has been shown to be valid and reliable. Duplicate measurements were made at rest and during four levels of exercise in 10 subjects. Heart rate values were comparable for exercise at the same work level during gas collection using the two systems, indicating that the metabolic stresses were similar. Oxygen consumption measurements were significantly lower using the K2 system compared with a metabolic measurement cart (MMC). There was no significant difference in VE, but RR was lower for measurements made with the MMC. Compared with the MMC, the K2 system uses a slightly different formula to calculate VO2 because the content of carbon dioxide in expired air is not measured. To determine differences resulting from the method of calculating VO2, MMC measurements were applied to the formula used by the K2 system, and K2 values were adjusted using the RER values obtained from the MMC. There were no differences between these calculated values and the values obtained directly from either the MMC or the K2 system. Consequently, we concluded that the lower VO2 values obtained with the K2 system were attributed to the method of collecting and analyzing expired air, rather than to the method of calculating VO2.

Cardiovascular responses to voluntary and nonvoluntary static exercise in humans.

We have measured the cardiovascular responses during voluntary and nonvoluntary (electrically induced) one-leg static exercise in humans. Eight normal subjects were studied at rest and during 5 min of static leg extension at 20% of maximal voluntary contraction performed voluntarily and nonvoluntarily in random order. Heart rate (HR), mean arterial pressure (MAP), and cardiac output (CO) were determined, and peripheral vascular resistance (PVR) and stroke volume (SV) were calculated. HR increased from approximately 65 +/- 3 beats/min at rest to 80 +/- 4 and 78 +/- 6 beats/min (P < 0.05), and MAP increased from 83 +/- 6 to 103 +/- 6 and 105 +/- 6 mmHg (P < 0.05) during voluntary and nonvoluntary contractions, respectively. CO increased from 5.1 +/- 0.7 to 6.0 +/- 0.8 and 6.2 +/- 0.8 l/min (P < 0.05) during voluntary and nonvoluntary contractions, respectively. PVR and SV did not change significantly during voluntary or nonvoluntary contractions. Thus the cardiovascular responses were not different between voluntary and electrically induced contractions. These results suggest that the increases in CO, HR, SV, MAP, and PVR during 5 min of static contractions can be elicited without any contribution from a central neural mechanism (central command). However, central command could still have an important role during voluntary static exercise.

Responses by lactating cows in commercial dairy herds to recombinant bovine somatotropin.

Cows (890) in 15 US herds were assigned randomly in equal numbers to control or bST injections (500 mg in a prolonged-release form every 14 d for 12 wk) within three stages of lactation (57 to 100, 101 to 140, and 141 to 189 d postpartum) and two parity groups (primiparous and multiparous). Yield and milk composition were monitored 1 d/wk for 16 wk including 2 wk pretreatment and 2 wk posttreatment. Increases in milk and FCM due to bST injections were less at 57 to 100 d than at 101 to 189 d postpartum (milk 3.6 vs. 5.5; FCM 3.9 vs. 6.1 kg/d per cow), and increases in milk and FCM were more for multiparous than for primiparous cows (milk 5.5 vs. 4.2; FCM 6.0 vs. 4.7 kg/d cow). Temporarily, concentration of milk fat increased and protein decreased; later, concentrations for control and injected cows were similar. Postinjection milk fat concentration decreased, but milk protein concentration increased temporarily. The net increase in milk (and FCM) varied significantly among herds from 2.9 to 7.6 kg/d per cow (mean, 4.9 kg). Responses in FCM were similar over a wide range of pretreatment yields. A great variety of feed ingredients were fed as total mixed rations, and nutrient concentrations varied greatly. The SCC were similar before, during, and after treatment, but increase in FCM of injected cows exhibited a negative correlation with pretreatment SCC. Changes in body condition score of sometribove-injected cows varied among herds (.25 to -.45) and averaged -.02 compared with .07 for controls. There was no pattern in incidence of mastitis during sometribove injections.

Cardiovascular responses to isokinetic trunk exercise.

Isokinetic trunk ergometers are relatively new devices. Because the stresses on the cardiovascular system when using these types of devices were unknown, the purpose of this study was to document the heart rate (HR) and blood pressure (BP) responses during a typical exercise session. Twelve subjects participated in three sessions of trunk flexion and extension exercises conducted on separate days. Exercises at one speed (ie, 60 degrees, 90 degrees, or 120 degrees/sec) were performed at each session. During each session, five 30-second exercise periods were separated by 60-second rest intervals. There were no differences in the HR and BP responses between exercise sessions at the three speeds. There was a progressive increase in HR to a value approximating 77% of predicted maximal HR by the end of the exercise sessions. Systolic blood pressure did not change from rest to exercise; diastolic blood pressure decreased initially and remained stable at the lower value throughout the exercise sessions. Several subjects reported light-headedness and dizziness during rest intervals. Because of the symptoms reported, we recommend that therapists monitor BP and observe patients for signs and symptoms of exercise intolerance when performing this type of exercise.

Effect of bovine somatotropin on metabolism of lactating dairy cows: energy and nitrogen utilization as determined by respiration calorimetry.

Effects of exogenous bovine somatotropin (bST) on energy and nitrogen utilization by high producing dairy cows were examined. Nine cows received bST (51.5 IU/d) or exipient (control) in a single reversal design involving 14-d treatment periods. Energy and nitrogen balances were measured in open-circuit respiration chambers. Yield of 4% solids-corrected milk was increased by 22% with bST treatment. Dry matter intake and the apparent digestibilities of dry matter, energy and nitrogen were not altered by treatment. The only significant component of nitrogen utilization that was altered by bST treatment was an increase in milk nitrogen secretion. Cows were in negative tissue nitrogen balance during the control period (-21 g/d) and tended to become more negative during the bST treatment period (-34 g/d). Heat energy loss and milk energy secretion were increased with bST treatment. Tissue energy balance was -1.1 Mcal/d during the control treatment period and the use of energy reserves with bST treatment decreased tissue energy balance to -9.8 Mcal/d. Changes in heat production with bST treatment were equal to those predicted from the changes in milk and body tissue. Overall, the results demonstrated that bST treatment increased yield of milk and milk components even when cows were in negative nitrogen and energy balance. Effects of bST were predominantly associated with nutrient partitioning, and observed heat loss (associated with maintenance and partial efficiencies of milk synthesis and tissue utilization) did not differ from predicted heat loss.

Effect of bovine somatotropin on metabolism of lactating dairy cows: influence on rates of irreversible loss and oxidation of glucose and nonesterified fatty acids.

Effects of bovine somatotropin (bST) on irreversible loss rate (ILR) and oxidation rate of glucose and nonesterified fatty acids (NEFA) were examined. Nine lactating cows received bST or excipient in a single reversal design using 14-d periods. Kinetic variables were estimated by compartmental analysis of blood metabolite and expired CO2 specific activity values obtained during infusion of [U-14C]glucose or [1-14C]palmitate. With bST treatment, milk energy yield increased by 31% but feed intake was unchanged. Blood glucose concentrations were not affected by treatment or correlated with any glucose kinetic variables. In the control period, glucose ILR was 12.1 mol/d with 66.5% utilized for milk lactose synthesis and 17.4% oxidized to CO2. Treatment with bST increased glucose ILR (+1.5 mol/d) and reduced glucose oxidation (-0.4 mol/d); this accommodated the additional glucose (+1.3 mol/d) required for the increase in lactose secretion. Increases in milk energy yield with bST treatment caused cows to be in a substantial negative net energy balance (-9.8 Mcal/d). No acute lipolytic response occurred with bST treatment, but plasma NEFA were chronically elevated (+104 mumol/L) and NEFA ILR increased (+2.3 mol/d). Increased NEFA turnover was primarily used for increased oxidation to CO2 (+0.5 mol/d) and 41% increase in milk fat (equal to approximately 1.3 mol fatty acids/d). For NEFA, plasma concentrations were correlated with ILR (r = +0.80), oxidation to CO2 (r = +0.74) and net energy balance (r = -0.78). Overall, bST resulted in an exquisite coordination of metabolism to meet nutrient needs for increased synthesis of milk components.

Somatotropin and lactation.

Somatotropin, which can now be produced by biotechnology, could have an enormous impact on the dairy industry. Milk yield has been increased up to 40% with daily injections of somatotropin. Cows adjust their nutrient intake to support this increase. Somatotropin does not adversely affect cows' health, although all studies to date have been for less than one complete lactation. The search for a single biochemical or physiological event to account for the effects of somatotropin on milk production is elusive. Coordinated changes in many tissues and physiological processes occur to support the increases in the synthesis of lactose, fat, and protein in the mammary gland. Changes in the irreversible loss and oxidation rates of two key metabolites, glucose and free fatty acids, can quantitatively account for increases in lactose and milk fat during the short-term administration of somatotropin. Similarly, feed intake and live weight changes can account for increases in milk production in the longer experiments. Parallels between physiological changes that occur during somatotropin administration and differences between genetically high and lower yielding cows are highlighted, and the rates of improvement that can be expected from various new technologies are quantified. Existing data on the safety of somatotropin to both the consumer and the animal are evaluated.