International Journal of Artificial Organs, Nov 1, 1983
The high mortality rate of patients afflicted with adult respiratory distress syndrome (ARDS) may... more The high mortality rate of patients afflicted with adult respiratory distress syndrome (ARDS) may be due, in part, to the hemodynamic changes and the barotrauma accompanying mechanical ventilation, especially when high positive pressure and oxygen tension are used. Recent experimental evidence suggests that prognosis may be improved by suspending ventilation: in the apneic condition, oxygenation can be maintained by transalveolar oxygen diffusion, while extracorporeal carbon dioxide removal (ECC02R), achieved with membrane lungs, assures C02 homeostasis. This technology, however, requires high blood flow rates, and is available only to very few specially equipped centers. We report results of experiments in dogs using an alternative approach to ECC02R during apnea. Dissolved C02 was converted to bicarbonate by the systemic infusion of NaOH at the rate of 0.15 mM/kg/min; the generated bicarbonate was then removed by hemodialysis against a bicarbonate-free dialysate, at a blood flow rate of 200 ml/min. Sodium and fluid balance were maintained by ultrafiltration. Observations in five dogs confirm that systemic pC02, TC02, and pH can be maintained well within physiologic ranges, and that prolonged apnea followed by full recovery can be achieved with this methodology. Mecause of the wide availability of dialysis equipment and expertise, and of lowerr extracorporeal blood flow requirements, ECC02R by alkali administration and hemodialysis offers a potentially attractive alternative approach to the use of membrane lungs in the apneic therapy of ARDS.
The accumulation of 99mtechnetium sulfur colloid (99mTcSC) was evaluated in 47 studies performed ... more The accumulation of 99mtechnetium sulfur colloid (99mTcSC) was evaluated in 47 studies performed on 19 renal transplant patients by comparing its transplant activity to its bone marrow accumulation. There was a diagnosis of rejection of 21 of 22 studies (96.5%) in which marked transplant accumulation was noted. In 11 studies of patients with a clinical diagnosis of post-transplant acute tubular necrosis (ATN), the transplant activity varied from none to moderate. Rejection developed in 5 of 6 studies with minimal to moderate accumulation. Normally functioning renal transplant patients, or those with ATN and no superimposed rejection, do not show evidence of 99mTcSC accumulation.
The accumulation of 99mtechnetium sulfur colloid (99mTcSC) was evaluated in 47 studies performed ... more The accumulation of 99mtechnetium sulfur colloid (99mTcSC) was evaluated in 47 studies performed on 19 renal transplant patients by comparing its transplant activity to its bone marrow accumulation. There was a diagnosis of rejection of 21 of 22 studies (96.5%) in which marked transplant accumulation was noted. In 11 studies of patients with a clinical diagnosis of post-transplant acute tubular necrosis (ATN), the transplant activity varied from none to moderate. Rejection developed in 5 of 6 studies with minimal to moderate accumulation. Normally functioning renal transplant patients, or those with ATN and no superimposed rejection, do not show evidence of 99mTcSC accumulation.
JAMA: The Journal of the American Medical Association, 1984
Dried smears of urinary sediment stained with Wright's stain were examined and compared i... more Dried smears of urinary sediment stained with Wright's stain were examined and compared in 20 selected patients with hematuria. In ten patients with microscopic hematuria and glomerular lesions demonstrated by renal biopsy, the urinary red cells were characteristically dysmorphic and hypochromic. This was distinctly different from the red cell morphology in ten patients with nonglomerular causes of hematuria, which was more like peripheral blood. The pathogenesis of the changes in red cell morphology seen in glomerular hematuria is unknown, but it appears not to be due to the urine composition per se. It is concluded that with some limitations, this simple, noninvasive technique may be useful in identifying a source of bleeding in the workup of hematuria.
Background: Preference for formula versus breast feeding among women of Chinese descent remains a... more Background: Preference for formula versus breast feeding among women of Chinese descent remains a concern in North America. The goal of this study was to develop an intervention targeting Chinese immigrant mothers to increase their rates of exclusive breastfeeding. Methods: We convened a focus group of immigrant women of Chinese descent in Vancouver, British Columbia to explore preferences for method of infant feeding. We subsequently surveyed 250 women of Chinese descent to validate focus group findings. Using a participatory approach, our focus group participants reviewed survey findings and developed a priority list for attributes of a community-based intervention to support exclusive breastfeeding in the Chinese community. The authors and focus group participants worked as a team to plan, implement and evaluate a Chinese language newborn feeding information telephone service staffed by registered nurses fluent in Chinese languages. Results: Participants in the focus group reported a strong preference for formula feeding. Telephone survey results revealed that while pregnant Chinese women understood the benefits of breastfeeding, only 20.8% planned to breastfeed exclusively. Only 15.6% were breastfeeding exclusively at two months postpartum. After implementation of the feeding hotline, 20% of new Chinese mothers in Vancouver indicated that they had used the hotline. Among these women, the rate of exclusive breastfeeding was 44.1%; OR 3.02, (95% CI 1.78-5.09) compared to women in our survey. Conclusion: Initiation of a language-specific newborn feeding telephone hotline reached a previously underserved population and may have contributed to improved rates of exclusive breastfeeding.
International Journal of Artificial Organs, Nov 1, 1983
The high mortality rate of patients afflicted with adult respiratory distress syndrome (ARDS) may... more The high mortality rate of patients afflicted with adult respiratory distress syndrome (ARDS) may be due, in part, to the hemodynamic changes and the barotrauma accompanying mechanical ventilation, especially when high positive pressure and oxygen tension are used. Recent experimental evidence suggests that prognosis may be improved by suspending ventilation: in the apneic condition, oxygenation can be maintained by transalveolar oxygen diffusion, while extracorporeal carbon dioxide removal (ECC02R), achieved with membrane lungs, assures C02 homeostasis. This technology, however, requires high blood flow rates, and is available only to very few specially equipped centers. We report results of experiments in dogs using an alternative approach to ECC02R during apnea. Dissolved C02 was converted to bicarbonate by the systemic infusion of NaOH at the rate of 0.15 mM/kg/min; the generated bicarbonate was then removed by hemodialysis against a bicarbonate-free dialysate, at a blood flow rate of 200 ml/min. Sodium and fluid balance were maintained by ultrafiltration. Observations in five dogs confirm that systemic pC02, TC02, and pH can be maintained well within physiologic ranges, and that prolonged apnea followed by full recovery can be achieved with this methodology. Mecause of the wide availability of dialysis equipment and expertise, and of lowerr extracorporeal blood flow requirements, ECC02R by alkali administration and hemodialysis offers a potentially attractive alternative approach to the use of membrane lungs in the apneic therapy of ARDS.
The accumulation of 99mtechnetium sulfur colloid (99mTcSC) was evaluated in 47 studies performed ... more The accumulation of 99mtechnetium sulfur colloid (99mTcSC) was evaluated in 47 studies performed on 19 renal transplant patients by comparing its transplant activity to its bone marrow accumulation. There was a diagnosis of rejection of 21 of 22 studies (96.5%) in which marked transplant accumulation was noted. In 11 studies of patients with a clinical diagnosis of post-transplant acute tubular necrosis (ATN), the transplant activity varied from none to moderate. Rejection developed in 5 of 6 studies with minimal to moderate accumulation. Normally functioning renal transplant patients, or those with ATN and no superimposed rejection, do not show evidence of 99mTcSC accumulation.
The accumulation of 99mtechnetium sulfur colloid (99mTcSC) was evaluated in 47 studies performed ... more The accumulation of 99mtechnetium sulfur colloid (99mTcSC) was evaluated in 47 studies performed on 19 renal transplant patients by comparing its transplant activity to its bone marrow accumulation. There was a diagnosis of rejection of 21 of 22 studies (96.5%) in which marked transplant accumulation was noted. In 11 studies of patients with a clinical diagnosis of post-transplant acute tubular necrosis (ATN), the transplant activity varied from none to moderate. Rejection developed in 5 of 6 studies with minimal to moderate accumulation. Normally functioning renal transplant patients, or those with ATN and no superimposed rejection, do not show evidence of 99mTcSC accumulation.
JAMA: The Journal of the American Medical Association, 1984
Dried smears of urinary sediment stained with Wright's stain were examined and compared i... more Dried smears of urinary sediment stained with Wright's stain were examined and compared in 20 selected patients with hematuria. In ten patients with microscopic hematuria and glomerular lesions demonstrated by renal biopsy, the urinary red cells were characteristically dysmorphic and hypochromic. This was distinctly different from the red cell morphology in ten patients with nonglomerular causes of hematuria, which was more like peripheral blood. The pathogenesis of the changes in red cell morphology seen in glomerular hematuria is unknown, but it appears not to be due to the urine composition per se. It is concluded that with some limitations, this simple, noninvasive technique may be useful in identifying a source of bleeding in the workup of hematuria.
Background: Preference for formula versus breast feeding among women of Chinese descent remains a... more Background: Preference for formula versus breast feeding among women of Chinese descent remains a concern in North America. The goal of this study was to develop an intervention targeting Chinese immigrant mothers to increase their rates of exclusive breastfeeding. Methods: We convened a focus group of immigrant women of Chinese descent in Vancouver, British Columbia to explore preferences for method of infant feeding. We subsequently surveyed 250 women of Chinese descent to validate focus group findings. Using a participatory approach, our focus group participants reviewed survey findings and developed a priority list for attributes of a community-based intervention to support exclusive breastfeeding in the Chinese community. The authors and focus group participants worked as a team to plan, implement and evaluate a Chinese language newborn feeding information telephone service staffed by registered nurses fluent in Chinese languages. Results: Participants in the focus group reported a strong preference for formula feeding. Telephone survey results revealed that while pregnant Chinese women understood the benefits of breastfeeding, only 20.8% planned to breastfeed exclusively. Only 15.6% were breastfeeding exclusively at two months postpartum. After implementation of the feeding hotline, 20% of new Chinese mothers in Vancouver indicated that they had used the hotline. Among these women, the rate of exclusive breastfeeding was 44.1%; OR 3.02, (95% CI 1.78-5.09) compared to women in our survey. Conclusion: Initiation of a language-specific newborn feeding telephone hotline reached a previously underserved population and may have contributed to improved rates of exclusive breastfeeding.
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