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Diets of six Steller sea lions (Eumetopias jubatus) were switched between a high (herring) and a low (squid) energy density food for 14 d to determine the effects on ingested prey mass, body mass, resting metabolic rate, and the heat increment of feeding. Body mass was measured daily, and resting metabolism was measured weekly by gas respirometry. Ingested food mass did not differ significantly between the squid diet and the control or the recovery herring diet periods. As a result of differences in energy density, gross energy intake was significantly lower during the squid diet phase than during either the control or recovery periods. As a result, sea lions lost an average of 1.1 kg/d, totaling 12.2% of their initial body mass by the end of the experimental period. The heat increment of feeding for a 4-kg squid meal was significantly lower than for a similarly sized meal of herring. Decreases in both absolute (24.0 to 18.0 MJ/d, -24%) and mass-corrected (903 to 697 kJ/d/kg0.67, -20%) metabolism were observed by the end of the squid feedings. This study suggests that sea lions can depress their resting metabolism in response to decreases in energy intake or body mass, regardless of satiation level.

Unlabelled: We prospectively studied topical lidocaine-prilocaine cream (EMLA) versus IV morphine in a double-blinded, randomized fashion for pain relief during thoracostomy tube (chest tube; CT) removal. Adult patients who had undergone thoracotomy or median sternotomy were randomized to receive either EMLA cream over CT sites transdermally for 3 h or IV morphine 0.5 h before CT removal. Pain behavior was observed and rated before, during, and after CT removal. Pain behavior increased less in the topical EMLA group (mean +/- SE, 4.4+/-0.39) compared with the IV morphine group (6.0+/-0.38; P < 0.01). No signs of infection were noted at the CT sites 24 or 48 h after CT removal. We conclude that EMLA cream is more effective than IV morphine in preventing the pain associated with CT removal., Implications: Postoperatively applying a topical anesthetic cream onto chest tube sites of chest surgery patients 3 h before chest tube removal is more effective than IV morphine in blunting pain response.

Sedation in children poses a great challenge, with the main concern one of safety. The importance of providing adequate sedation to children was realized only in the last decade and a half, and relevant data are severely lacking. Use of potent sedative agents is not without risk. Children are given sedative agents in a wide variety of settings by practitioners with different degrees of experience with the drugs and management of adverse effects. Controversial issues must be addressed in this area, and appropriate tools developed to measure sedation and individualize treatment based on the drugs' pharmacokinetic and pharmacodynamic properties.

The heat increment of feeding (HIF) was measured in six captive, juvenile Steller sea lions (Eumetopias jubatus), fed meals of either 2 or 4 kg of herring. HIF was calculated as the post-prandial increase in metabolism above baseline levels, and was measured using open-circuit (gas) respirometry. It averaged 12.4 +/- 0.9% (SE) of ingested energy intake for the 4-kg meal trials, and 9.9 +/- 0.9% for the 2-kg meal size. The effect lasted 8-10 hr for the larger meal size. Metabolism peaked 3.7 hr after feeding, and was 2.13 times higher than baseline levels. For the 2-kg meal size, the effect lasted 6-8 hr, with metabolism peaking 2.8 hr after ingestion at 1.76 times baseline levels. Our estimates of HIF for Steller sea lions are at the lower end of estimates for terrestrial mammals, and are consistent with estimates for other marine mammals.

Cardiopulmonary bypass (CPB) creates a myriad of pharmacological and physiological changes. Some of these changes have been studied in isolated in vitro studies. Integrating an in vitro system into an in vivo process is so complicated that many pharmacological studies simply avoid the bypass period. For the most part, the studies that do examine the bypass period deal with a single drug, reporting how it does or does not produce a predicted concentration on initiation, maintenance and termination of CPB. Based on the isolated results of these studies, this review hypothesizes a model that explains how different substances interact with the CPB system. A summary of the review's findings include the following: 1) drugs with a smaller volume of distribution are more likely to be effected; 2) the pharmacokinetic effects of lipophilic drugs undergo more alterations than hydrophilic drugs; and 3) protein binding minimizes alterations of lipophilic drugs and increase alterations of hydrophilic drugs.

Dreissenid mussels, Dreissena polymorpha and D. bugensis, were found to be infected by the naidid oligochaete Chaetogaster limnaei at four sites in the St. Lawrence River. This is the first report of this species infecting dreissenids anywhere in the world. Most worms inhabited the mantle cavity, where they caused erosion of the mantle and gill epithelia as determined by histopathological examination. Others penetrated various tissues; one had invaded the ovary and was feeding on oocytes and ovarian tissues. Of 606 mussels examined, 166 (27.4%) harbored at least 1 C. limnaei. The prevalence varied between 1% and 80%, depending on the collection site and date. The worms were slightly but significantly more prevalent in D. bugensis than in D. polymorpha. The intensity ranged from 1 to 18 worms per infected host. Variations in prevalence and intensity were not related to the size or sex of the host, but the data did suggest some seasonality.

The stability of propofol in three parenteral nutrient (PN) solutions was studied. Nine combinations of three PN solutions (with amino acid concentrations of 1.5, 2.5, and 5.0%) and three propofol concentrations (0.5, 2.0, and 3.0 mg/mL) were prepared in triplicate and stored at 22 degrees C under fluorescent light. Duplicate samples were visually inspected for color changes, precipitation, or gas formation, and the pH of the samples was determined. These samples were evaluated for propofol content by high-performance liquid chromatography at zero, one, three, and five hours. The stability of the vehicle for propofol injection (similar in composition to fat emulsion) was evaluated by visual inspection, pH determination, and particle-size measurements at zero, one, three, and five hours. The concentration of propofol in all of the propofol-PN combinations remained greater than 90% of the initial concentration except for the combination of propofol 0.5 mg/mL and the 1.5% amino acid PN solution, which contained only 72% of the initial propofol concentration five hours after the start of the study. Visual examination revealed no evidence of color change, precipitation, gas formation, creaming, or streaking in any of the propofol-PN solution combinations. No substantial changes in pH occurred. The particle size of the vehicle for propofol remained relatively constant throughout the study period. Propofol 2 and 3 mg/mL was stable for five hours during simulated Y-site injection with PN solutions containing 1.5, 2.5, and 5% amino acids. Propofol 0.5 mg/mL was stable during simulated Y-site injection with the same PN nutrition solutions for five hours, except for the solution containing 1.5% amino acid.

The stability of midazolam hydrochloride in flavored gelatin was evaluated after storage at 4 degrees C for 14 days and at -20 degrees C for 28 days. A flavored liquid gelatin mixture was prepared and mixed with midazolam hydrochloride injection in final concentrations of midazolam 1 and 2 mg/mL. Gelatin cups containing 5 and 15 mg of midazolam were prepared by measuring appropriate volumes of the gelatin stock solutions and were stored in a refrigerator at 4 degrees C or in a freezer at -20 degrees C. Immediately after preparation and at 7 and 14 days, three refrigerated and three frozen gelatin samples of each midazolam concentration were visually inspected, tested for pH, and assayed for midazolam concentration by high-performance liquid chromatography. The frozen gelatin samples were also evaluated at 21 and 28 days; three whole and three partial gelatin samples were assayed for midazolam content to determine the uniformity of drug distribution within each sample. All samples maintained greater than 96% of the initial midazolam concentration throughout the study. There was no appreciable change in color, odor, or pH. The midazolam content of the gelatin in the cups was uniform. An extemporaneously compounded preparation of midazolam hydrochloride in flavored gelatin was stable when stored for 14 days at 4 degrees C and for 28 days at -20 degrees C. Distribution of midazolam hydrochloride in the gelatin was uniform.

The compatibility and stability of midazolam hydrochloride in three parenteral nutrient (PN) solutions and the stability of 15 amino acids in the presence of midazolam hydrochloride were studied. Six combinations of three PN solutions with amino acid concentrations of 1.5%, 2.5%, and 5% and two midazolam concentrations (0.1 and 0.5 mg/mL) were prepared in triplicate and stored at room temperature under normal fluorescent lighting. Duplicate samples were visually inspected for color change, precipitation, or gas formation and tested for pH. The samples were evaluated for midazolam and amino acid content by high-performance liquid chromatography at zero, one, three, and five hours. Midazolam and amino acid concentrations did not change significantly during the study. There was no evidence of color change, precipitation, or gas formation with any midazolam-PN solution combination when the combinations were examined visually and under a microscope, and no substantial changes in pH occurred. Midazolam 0.1 and 0.5 mg/mL (as the hydrochloride salt) was stable in the three PN solutions studied; in addition, the amino acids present in the 1.5%, 2.5%, and 5% amino acid PN solutions were stable when combined with midazolam at concentrations of 0.1 and 0.5 mg/mL.

Increased pulmonary blood flow and pulmonary hypertension are frequent problems in infants with congenital heart disease. Although the use of pulmonary artery banding to limit pulmonary blood flow has decreased, the procedure may still be beneficial in certain forms of complex heart disease. The ability to noninvasively relieve the obstruction caused by the band may significantly reduce later operative complexity or even avoid reoperation entirely. The present study evaluated the effectiveness of a balloon-dilatable pulmonary artery band. Twenty 1-week-old dogs had a band of an absorbable suture material (Vicryl; Ethicon, Inc., Somerville, N.J.) placed around the main pulmonary artery. Eight dogs underwent angioplasty 6 months after band placement and also underwent follow-up catheterizations 3 and 6 months after angioplasty. Balloon angioplasty acutely reduced both the right ventricle-pulmonary artery pressure gradient (from 37 +/- 7 mm Hg to 3 +/- 1 mm Hg, p less than 0.001) and the right ventricular systolic pressure (from 62 +/- 8 mm Hg to 32 +/- 2 mm Hg, p less than 0.01). At follow-up the gradient remained low, measuring 4 +/- 1 mm Hg at 3 months and 3 +/- 1 mm Hg at 6 months. Twelve dogs did not undergo balloon dilatation until 12 months after band placement to determine whether any obstruction persisted and whether the band could be relieved after long-term placement. These 12 dogs had progressive increases in right ventricle-pulmonary artery gradient, from 27 +/- 3 mm Hg at 6 months to 43 +/- 4 mm Hg at 12 months. Ten of these dogs underwent dilation 1 year after pulmonary artery band placement. This dilation significantly reduced the right ventricular outflow tract gradient (from 43 +/- 4 mm Hg to 1 +/- 1 mm Hg, p less than 0.001). The remaining two dogs underwent successful partial dilation of the band 12 months after placement. This study demonstrated that a pulmonary artery band of absorbable suture material maintains effective right ventricular outflow tract obstruction for at least 1 year. Additionally, the effect of the pulmonary band can be successfully and persistently relieved.

The pathophysiology, assessment, and pharmacologic management of acute pain in infants and children are reviewed, and the mechanism of action, pharmacokinetics, clinical efficacy, adverse effects, and dosages of opioid analgesics, nonopioid analgesics, and local anesthetics used for regional blocks are discussed. The pathophysiology of pain and the physiologic rationale for treatment of pain are similar in children and adults. Severe pain can be controlled by i.v. or epidural administration of opioid analgesics. Neonates are more susceptible to the depressant effects of opioids, and opioid analgesia must be administered with caution in infants who are not receiving mechanical ventilation because of the associated risk of respiratory depression. Patient-controlled analgesia is a useful technique in older children. Acetaminophen and NSAIDs are useful for relieving milder pain of noninflammatory and inflammatory origin, respectively. Epidural or intrathecal administration of local anesthetics provides regional analgesia with minimal physiologic alterations. Topical application of local anesthetics is effective for many minor procedures. A variety of pain management techniques are available for the management of acute pain in pediatric patients. The development of drugs having fewer adverse effects and noninvasive administration techniques will be important research priorities in the coming years.

Routine gynecologic care for persons with mental retardation may be difficult to provide, especially to those women who do not allow a pelvic examination to be performed. Of 275 women referred to a multidisciplinary clinic addressing the reproductive health concerns of mentally retarded women, 61 patients (22%) did not allow a gynecologic examination to be performed. The administration of ketamine alone, midazolam alone, or a combination of midazolam and ketamine allowed for the successful performance of a gynecologic examination in 81% of previously uncooperative women. No adverse effects of the medications were noted. We conclude that sedation of difficult-to-examine, mentally handicapped women can be safely performed in the outpatient setting, thus avoiding the need for general anesthesia and its inherent risks.

This retrospective study examines data from 55 patients sedated in a paediatric intensive care unit (PICU) with midazolam. Midazolam sedation was initiated with a bolus of 0.25 mg.kg-1 followed by a continuous infusion of 0.4-4 micrograms.kg-1.min-1. Physiological and metabolic parameters, infusion rates, duration, and sedation scores were monitored. Midazolam infusions were effective in sedating all the children studied during all or part of their PICU admission. The median duration of sedation was 74 h with a range of 4 to 1272 h. Haemodynamics were unchanged. Of the patients 46% were effectively alimented by the enteral route, and enteral alimentation was successful in all patients in whom it was attempted. Unassisted ventilation occurred in 44% of the patients during infusion. Oxygen consumption was 28% lower than in the control. Disadvantages of midazolam infusion have included inability to sedate during extracorporeal membrane oxygenation and development of acute tolerance.

The Equal Employment Opportunity Commission (EEOC) recently issued its final regulations on the Americans with Disabilities Act (ADA). Although the regulations offer some guidance for employers on how to comply with the Act, they fail to provide specific answers to the many complicated compliance questions that will surely arise. Further, the regulations are almost totally silent on certain critical issues related to insurance, workers' compensation, and potential conflicts between ADA obligations and terms of collective bargaining agreements. The EEOC has essentially left the resolution of many important ADA questions to case-by-case determination and the litigation process.

To evaluate the results of palliative surgery for hypoplastic left heart syndrome, we reviewed the records of 57 infants who underwent first-stage reconstruction at our institution between July 1983 and April 1989. Of the 57 infants, 12 (21%) are long-term survivors and 45 (79%) have died. Thirty-one infants died within the first 30 days after surgery. Twenty-six of the 31 early deaths occurred within the first 24 hours after surgery. Causes of early mortality were low cardiac output (23), sepsis (two), sudden death (two), pulmonary vein atresia (three), and cardiac transplant (one). Late death occurred in 14 infants due to sepsis (three), sudden death (four), and death at reoperation (seven - three after Fontan procedure, three after shunt replacement, and one after transplant). Of the 31 patients who survived more than 24 hours, the complications noted by echocardiography and confirmed by catheterization when reoperation was indicated were significant arch obstruction (13%), branch pulmonary artery stenosis (23%), small atrial septal defect (16%), inadequate shunt (26%), neoaortic regurgitation (13%), tricuspid regurgitation (13%), ventricular dysfunction (29%), thrombus (6%), and superior vena cava obstruction (3%). Of the 31 patients who survived more than 24 hours, 16 additional palliative surgical procedures were performed in eight patients. These procedures included arch reconstruction (four), additional shunt (four), Glenn shunt (three), atrial septectomy (two), coarctation balloon angioplasty (two), and pulmonary artery reconstruction and reshunting (one). Of the 12 long-term survivors, four have had a successful Fontan procedure, one has had a transplant, and seven are awaiting a second-stage procedure. Thus, 69% of all deaths occurred within the first 30 days of surgery, and 58% of all deaths occurred within the first 24 hours due to cardiovascular collapse.(ABSTRACT TRUNCATED AT 250 WORDS)

The membrane oxygenator has replaced the bubble oxygenator in a wide variety of clinical settings. The membrane oxygenators now manufactured can be grouped into three categories based on composition and design: (1) silicone with a true membrane structure; (2) polypropylene with a microporous sheet; and (3) polypropylene with a microtubular structure. The capacity for fentanyl uptake by membrane oxygenators from these three categories was studied in vitro. Representative membrane samples were incubated in solutions containing tritiated fentanyl in Normosol-R (Abbott, North Chicago, IL) with pH adjusted to 7.4 at 37 degrees C. Fentanyl analysis was performed using liquid scintillation and radioimmunoassay techniques. The uptake of fentanyl at various concentrations (340 to 10 ng/mL) was studied. The SciMed (type 1; SciMed, Minneapolis, MN) membrane showed the greatest capacity for fentanyl uptake at all concentrations. The SciMed oxygenator was capable of binding 130 ng fentanyl/cm2 membrane. When presented with a smaller concentration (less than or equal to 20 ng/mL) of fentanyl, the membrane was able to extract all available fentanyl from solution. All of the microporous polypropylene oxygenators (types 2 and 3) absorbed significantly less fentanyl than did the SciMed brand. When exposed to 10 or 20 ng/mL, the Shiley and Omnis brands (type 2) absorbed 0.1 and 0.4 ng/cm2, respectively. Using the higher fentanyl concentrations (greater than or equal to 200 ng/mL) uptake by the Omnis membrane was 11 ng/cm2 compared with only 2 ng/cm2 by the Shiley. The Bentley BCM 7 and Terumo Capiox II 08 microtubular microporous membranes (type 3) did not show absorption of fentanyl using isolated or intact membrane models.(ABSTRACT TRUNCATED AT 250 WORDS)

The incidence and predisposing factors for bilateral branch vein occlusions were evaluated in a retrospective study. Complete medical and ocular histories of 49 patients with angiographically proven branch vein occlusion were studied. Nine of these patients had bilateral vein occlusions that were unsuspected clinically. Hypertension was the only significant predisposing risk factor for this occurrence. The relationship between control of the hypertension and retinal vascular disease could not be evaluated in this study.

A patient had visual field loss and optochiasmatic arachnoiditis and subsequently developed other evidence of multiple sclerosis. The possibility is raised that many of the "idiopathic" cases of optochiasmatic arachnoiditis may have a similar origin. Special emphasis is placed on the functional role of the fibrosis in the pathogenesis of optochiasmatic arachnoiditis.

Experimental branch vein occlusion by laser photocoagulation in the rhesus monkey leads to early, marked, and lasting reduction of blood flow to the affected retinal region. The radioactive microsphere method demonstrates this reduction of blood flow in both gamma counting and autoradiography. The reduction of flow becomes evident as early as 2 hours after occlusion and persists up to 1 week. The mechanism of the altered flow is discussed.

Two patients with visual loss after cataract extraction were found to have prominent pallid optic disc edema, peripapillary hemorrhage, and cystoid maculopathy. A diagnosis of anterior ischemic optic neuropathy, with coincidental aphakic cystoid macular edema, was initially considered. The clinical course, however, favored a diagnosis of visual loss secondary to maculopathy. In both cases, fluorescein angiography disclosed leakage of fluorescein dye from macula, optic disc, and peripapillary foci. Fluorescein angiography and stereo color photographs of 51 patients with aphakic cystoid maculopathy were reviewed to determine the incidence of optic disc edema. Although optic disc swelling was rarely recognized on fundus photography, optic disc hyperfluorescence was observed in 75% of cases.

A report is presented on the use of the carbon dioxide (CO2) laser for the removal of recalcitrant warts of hands and feet of 27 patients. Of the 27 patients 22 (81%) required only one laser treatment to eradicate warts and remain free of lesions at the 6-month follow-up visit. The other patients required up to 3 retreatments with the laser during the first 6 months to remain free of lesions at a 6-month follow-up. The CO2 laser provided a bloodless surgical field, accurate control, minimal postoperative pain, and decreased postoperative infection. The authors conclude that, while the CO2 laser is not without its disadvantages, it should be considered an important adjunct in the treatment of difficult, widespread, or recalcitrant verrucae.

Two patients had uniocular visual loss after methylprednisolone acetate (Depo-Medrol) injection for control of chronic inflammatory conditions in the nose. The cause of the visual loss was embolic retinal and choroidal vascular occlusion. The emboli were presumably aggregates of microcrystals of methylprednisolone acetate.

A 69-year-old black woman had ocular findings consistent with birdshot retinochoroidopathy; these included cream-colored depigmented spots at the level of the retinal pigment epithelium and vitreitis. She also had peripheral retinal neovascularization with localized vitreous hemorrhage. There were no laboratory or systemic findings consistent with other disease entities.

Two patients with malignant histiocytosis were found to have capillary occlusion by aggregates of neoplastic histiocytes, in skeletal muscle in one, and in renal glomeruli in the other. One patient had clinical evidence of similar occlusions in the arterioles and capillaries of the ocular fundi. Occlusion of small vessels by tumour cells may explain the confusion of both patients.

The ability to deliver fluid to the pediatric patient is a function of many variables. In addition to patient-specific factors such as patient age, size, and weight, and venous size, number, and character, there exist further universal limitations inherent in the equipment which is utilized. Mechanical variables include cannula number, length, brand, and gauge; tubing length, band, style, and gauge; use of extensions; and presence and type of pressure system. This study evaluated a few of these variables. The flow rates were determined for 10 brands of 20-, 22-, and 24-gauge peripheral intravenous catheters. The catheter brands were divided into two groups, slow or faster. The differences in flow between the two categories were statistically significant. The disparities between the slowest and most rapid catheters of the same gauge were only 6.6, 5.4, and 7.7 ml/min for the 20, 22, and 24 gauges, respectively. The tubing apparatus was also a significant determinant of flow. The addition of any extensions further decreased flow. The magnitude of this slowing was a function of both the tubing and the type of extension.

A 50-year-old white woman had bilateral visual loss associated with fever, chills, and myalgias. Her systemic complaints responded to steroid therapy but visual reductions and retinal lesions have persisted for one year. Fluorescein angiographic findings are identical to those seen in acute retinal pigment epitheliitis but the clinical history is more suggestive of acute macular neuroretinopathy. These two entities may represent different clinical expressions of the same disease.

The safety and efficacy of epidural morphine injected into the caudal space for control of postoperative pain following open cardiac surgery in children was studied. Thirty-two children between the ages of 2-12 yr for whom early postoperative tracheal extubation was anticipated were randomly assigned to control and study groups. Study subjects received a caudal injection of preservative free morphine sulfate (0.075 mg/kg) in preservative-free normal saline (5-10 ml) following completion of surgery, but prior to awakening and extubation of the trachea. Supplemental intravenous morphine administration and pain scores were recorded for 24 h. Patients in the study group received significantly less (P less than 0.03) morphine (0.32 mg.kg-1.24 h-1) and had significantly lower pain scores than did patients in the control group (0.71 mg.kg-1.24 h-1). The mean duration of complete analgesia in patients receiving caudally administered morphine was 6 h (range 2-12), but decreased analgesic requirements were noted for the entire 24 h. No respiratory depression was evident by clinical variables or repeated arterial blood gas values. Nausea without vomiting occurred in 4/16 patients in the study group. No patient described pruritus. The authors were unable to evaluate the occurrence of urinary retention because all patients had indwelling urinary catheters. They found caudal epidural morphine to be safe and effective in the treatment of postoperative pain in children following open heart surgery.