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Introduction: Severe burn injury is known to delay gastric emptying in both animals and humans; however no data are available on its effect on gastric myoelectrical activity (GMA). We aimed at studying the effect of burn injury on GMA as it might contribute to burn‐induced delayed gastric emptying. Methods: Surgical implantation of a pair of cardiac pacemaker wires onto the stomach serosa was carried out in 20 adult male Sprague‐Dawley rats. Following recovery, GMA was recorded for 30 min in both fasting and fed conditions. The following day, rats received a sham or a 3rd degree scald burn injury under anesthesia. Proper fluid resuscitation and analgesia were given to all animals. Six hours after sham/burn injury, GMA was recorded for 30 min again in both fasting and fed conditions. A methylcellulose meal was mixed with phenol red (marker), so that the percentage of gastric emptying could be calculated based on the amount of phenol red recovered from the stomach. GMA parameters were computed using previously validated spectral analysis software developed in our laboratory, including dominant frequency/power and percentages of normal slow waves, bradygastria, tachygastria and arrhythmia. The normal slow wave frequency range was 4–6 cycles per min (cpm) in rats, while ≤4 cpm and ≥6 cpm were considered bradygastria and tachygastria respectively. Arrhythmia was established if the slow wave frequency had no specific range. Results: 1) None of GMA parameters showed any statistical differences in the fasting condition after burn (p > 0.05). 2) Significant changes in GMA with burn were only observed postprandially, including: a decrease in dominant frequency (4.5 ± 0.2 vs. 5.1 ± 0.2, p = 0.002) and in the percentage of normal slow waves (67.2 ± 7.3 vs. 84.5 ± 4.1, p = 0.02) and an increase in the percentage of bradygastria (24.7 ± 6.8 vs. 9 ± 3.9, p = 0.02). 3) The percentage of gastric emptying was decreased after burn to 40.3 ± 6.5 vs. 77 ± 3.2 in previously obtained controls (p = 0.0003); however, it did not correlate significantly to any of GMA parameters before or after burn, whether in fasting or in fed conditions (p > 0.05). Conclusion: Severe burn injury impairs both GMA and gastric emptying in rats. However, these alterations are not correlated with each other, suggesting that gastric dysrhythmia is a manifestation of burn rather than the cause of burn‐induced delayed gastric emptying. 相似文献
185.
Objective : To study the effect of phototherapy for neonatal hyperbilirubinaemia on thyroid function as neonatal thyroid screening is sometimes performed during exposure to phototherapy. Methodology : Infants with non-haemolytic hyperbilirubinaemia were sequentially allocated to fibre-optic phototherapy, conventional daylight phototherapy, or a combination of both. Bilirubin concentration was monitored 12 hourly by capillary blood sampling; venous blood was sampled for thyroid stimulating hormone (TSH) and free thyroxine (fT4) determinations, at start of exposure, at 24 h, end of exposure and 1 day later. Comparable unexposed infants served as controls. Results : All 123 study infants and 25 controls remained well during the study. Bilirubin levels declined during phototherapy, being most rapid in the combination group. The TSH and fT4 values at start of exposure were 3.86 ± 0.41 mU/L (mean ± SEM) and 33.20 ± 1.16 pmol/L, respectively, in the fibre-optic group, 3.62 ± 0.38 mU/L and 37.22 ± 1.76 pmol/L in the daylight group, and 4.40 ± 0.48 mU/L and 29.91 ± 1.13 pmol/L in the combined group, compared with 5.77 ± 0.40 mU/L and 34.46 ± 1.68 pmol/L in the control group. The TSH and fT4 values declined with increasing age in the phototherapy and control groups with end of exposure values of 2.90 ± 0.28mU/L and 27.71 ± 0.71 pmol/L, 2.77 ± 0.31 mU/L and 33.52 ± 1.22pmol/L, and 3.44 ± 0.30 mU/L and 27.54 ± 0.88 pmol/L, respectively, compared with 4.21 ± 0.61 mU/L and 27.19 ± 2.33 pmol/L (at 72 h) in the control group. The pattern of TSH and fT4 decline in the exposed and control groups was similar, being related to increasing age. Conclusions : The validity of neonatal thyroid screening is not affected by fibre-optic or conventional phototherapy or by both combined. 相似文献
186.
Non-traumatic massive subdural haematoma is a rare condition in newborn infants and is usually associated with hereditary coagulation disorders or congential vascular malformation. Its occurrence in preterm very low birthweight infants secondary to systemic bacterial infection has not been reported. We describe two extremely preterm neonates who developed massive subdural haematoma as a result of Gram-negative septicaemia and disseminated intravascular coagulation. Both infants suffered severe parenchymal cerebral injury and hydrocephalus. Clinicians should be aware of this unusual and catastrophic complication if a very low birthweight infant with severe sepsis and disseminated intravascular coagulation suddenly deteriorates despite successful treatment with antibiotics. Radiological imaging by cranial ultrasound or computed tomography scanning should be routinely considered in all such infants for the detection of intracranial bleeding. 相似文献
187.
Quantification of pleural effusions: sonography versus radiography 总被引:11,自引:0,他引:11
Eibenberger KL; Dock WI; Ammann ME; Dorffner R; Hormann MF; Grabenwoger F 《Radiology》1994,191(3):681
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Hovsepian DM; Bonn J; Eschelman DJ; Shapiro MJ; Sullivan KL; Gardiner GA Jr 《Radiology》1994,190(1):137
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KL Tan 《Acta paediatrica (Oslo, Norway : 1992)》1996,85(3):277-279
Exchange transfusion for severe neonatal jaundice is a tedious and expensive procedure with high morbidity and mortality rates, and is followed by a prompt and marked bilirubin rebound. It has largely been replaced by phototherapy, which though more gradual in its effect results in a prolonged reduction of the bilirubin concentration. Its efficacy is influenced by the gestational age, birthweight and postnatal age of the infant, the aetiology of the jaundice, and the spectral emission and intensity (dose) of the light; its dose-response relationship enables it, at the optimal dose, to control very severe jaundice or a rapidly rising bilirubin concentration, including severe haemolysis. Its relative freedom from complications together with its non-invasive nature, ease of usage and convenience has resulted in widespread acceptance in virtually all neonatal units. 相似文献