Search PubMed⌕ Search

Biomedical subjects

B S Carter

Publications and source records attributed to B S Carter.

At least 37 records · Page 2Linked to original sources
PubMed1998

Prospective validation of a scoring system for predicting neonatal morbidity after acute perinatal asphyxia.

OBJECTIVE: To prospectively validate a previously reported scoring system for identifying the near-term infant at risk for the multiple organ system sequelae of acute perinatal asphyxia. STUDY DESIGN: Prospective observational study. SETTING: Three Denver teaching hospitals, each providing comprehensive obstetric care. SUBJECTS: Newborn infants of 36 weeks or more gestation. INTERVENTION: None. STATISTICAL ANALYSIS: Chi-squared analysis with Fisher's exact test. OUTCOME: Scores consisting of graded abnormalities in fetal heart rate monitoring, umbilical arterial base deficit, and 5-minute Apgar score were calculated by the research nurse after admission of the infant to the nursery (range of possible scores, 0 to 9). A second nurse, blinded to these data, prospectively followed the newborn's hospital course for multiple organ system morbidity. RESULTS: Three thousand two hundred thirty-eight newborns were studied; 366 required neonatal intensive care unit admission. Eleven newborns had a score > or = 6 (mean umbilical artery pH = 6.98, base deficit = 17.1 mEq/L). Morbidities in these 11 newborns included seizures (2), hypoxic-ischemic encephalopathy (5), respiratory distress (9), hypotension (7), renal dysfunction (9), hypoglycemia/hypocalcemia (4), and thrombocytopenia or disseminated intravascular coagulopathy (3). The odds ratio (OR) and 95% confidence interval (CI) for newborns admitted to the neonatal intensive care unit with a score > or = 6 for having multiple organ system morbidity, defined as three or more affected organ systems, was 38.5 (95% CI, 9.2 to 127.8). The scoring system showed a stronger relationship with multiple organ system morbidity than did isolated individual indicators commonly used to identify asphyxia calculated on the same subjects: for those with pH < 7.00, OR 24 (95% CI, 6.4 to 94.1); base deficit > or = 10 mEq/L, OR 4.5 (95% CI, 1.9 to 10.3), and 5-minute Apgar score < or = 3, OR 7.4 (95% CI, 1.3 to 38.1). CONCLUSION: This scoring system, encompassing both immediate intrapartum and postpartum measures and acid-base status proximate to the time of delivery, is useful for rapidly identifying the term and near-term newborn at risk for multiple organ system morbidity after acute perinatal asphyxia.

Acidosis↗
PubMed1998

Biological aggressiveness of hereditary prostate cancer: long-term evaluation following radical prostatectomy.

PURPOSE: We answer the question of whether, following radical prostatectomy, prostate cancer in patients with a family history of prostate cancer relapses biochemically at the same rate as prostate cancer in appropriately matched patients with no family history. MATERIALS AND METHODS: The study was performed in 2 parts. In both parts prostate specific antigen (PSA) progression was defined as a postoperative elevation in serum PSA greater than 0.2 ng./ml. Part 1 included 656 patients who underwent radical prostatectomy by the same surgeon. Men with a family history of prostate cancer in a father or brother (94) were compared to those with no history of prostate cancer in a father or brother (562). Part 2 comprised 52 men with a family history of prostate cancer consistent with hereditary prostate cancer (HPC). HPC is defined as a family with 3 generations affected, 3 first-degree relatives affected or 2 relatives affected before age 55 years. Each member of this HPC group was matched by postoperative Gleason score and postoperative pathological stage with a patient who also underwent radical prostatectomy in the same time frame by the same surgeon but who reported no family history of prostate cancer by telephone interview and questionnaire. RESULTS: In part 1, 94 probands (14%) reported a history of prostate cancer in the father or in at least 1 brother. The remaining 562 probands (85%) reported no known history of prostate cancer in the father or brother(s). There was no statistically significant difference in the probability of maintaining an undetectable PSA between these 2 groups. In part 2, 45 of 52 pairs (87%) were matched identically for all matching criteria. Mean follow time for the sporadic and hereditary groups was 5.4 and 5.1 years, respectively. There was no statistically significant difference in the probability of maintaining an undetectable PSA between the 2 groups. CONCLUSIONS: Men with an affected father or brother, or those with a family history consistent with HPC have the same outcome following radical prostatectomy as men with no family history of the disease. Combined with our previous studies, these findings suggest that there is no biologically important difference between hereditary and sporadic prostate cancers.

Disease Progression↗
PubMed1998

A proposed comprehensive grading system to predict outcome for surgical management of intracranial aneurysms.

OBJECTIVE: By conducting a review of clinical outcomes for patients with aneurysms treated using current microneurosurgical techniques and intensive care unit management, we determined that grading systems based only on the clinical condition of the patient failed to produce a significant stratification of outcome between individual grades of patients. We hypothesized that outcome prediction for patients surgically treated for intracranial aneurysms could be improved by including factors other than clinical condition that were also strongly associated with outcome. METHODS: To identify potential factors for inclusion in a risk prediction tool, we conducted a multivariate logistic regression analysis of patient- and lesion-specific factors suspected to be associated with outcome in a series of 434 aneurysm operations. Factors that were strongly associated with outcome were used to develop a comprehensive grading system. In the system, 1 point is assigned for Hunt and Hess Grade IV or V, Fisher Scale score of 3 or 4, aneurysm size greater than 10 mm, patient age older than 50 years, and if the lesion is a giant (> or =25 mm) posterior circulation lesion. By adding the total points, a 5-point grading system (Grades 0-5) is obtained. RESULTS: Age of patient, size of aneurysm, severity of subarachnoid hemorrhage (Fisher Scale evaluation of density of blood present as revealed by computed tomography), and clinical condition (Hunt and Hess grade) were each independently and strongly (relative risk, >4) associated with long-term outcome. In addition, there was a trend for increased risk with larger (>25 mm) posterior circulation lesions. When applied to the study population, individual grades on the new grading scale correlated well with actual outcome. In a prospective assessment of the system as applied to an additional 72 operations with at least 1 year of follow-up, the correlation of individual grades and outcome was strong and validated the retrospective findings. CONCLUSION: This new grading system is easy to apply, separates patients into groups with markedly different outcomes, and is comprehensive, allowing for more accurate prediction of surgical outcome for both unruptured and ruptured cerebral aneurysms.

Adult↗
PubMed1998

Neonatal pharyngeal pseudodiverticulum mimicking esophageal atresia.

Pseudodiverticulum of the hypopharynx is an infrequent but potentially serious complication of orogastric or nasogastric tube insertion and endotracheal intubation. We report two cases of injury to the hypopharynx resulting in a pseudodiverticulum of the hypopharynx that was initially diagnosed as esophageal atresia. Both cases were managed successfully by conservative therapy. We also review the literature regarding neonatal pharyngeal pseudodiverticulum.

Diagnosis, Differential↗
PubMed1998

The neonatologist as primary care physician.

Although trained first as pediatricians, neonatologists are not typically viewed as primary care physicians. However, given their particular training and expertise, patient population, and interaction with families as the newborn's first physician in many settings, neonatologists may rightly be viewed as the most appropriate primary care physician for newborns with medical or surgical problems. We review the fundamental underpinnings of primary care medicine with particular attention to how the neonatologist functions in such capacities. Neonatologist can contribute greatly to ensuring continuity of care for the sick newborn, the comprehensive nature of that care, and the coordination of care. Neonatologists' interactions with elements of the community to which the newborn will be discharged are an asset, as is their ability to work as part of a team. Given recent changes in practice management, the availability of neonatologists in the United States, and the desire for full-service mother and infant care capabilities in community hospitals, the primary care role of neonatologists bears recognition and support in today's changing healthcare marketplace.

Continuity of Patient Care↗
PubMed1997

One-year outcome after decompressive surgery for massive nondominant hemispheric infarction.

OBJECTIVE: Massive cerebral infarction is often accompanied by early death secondary to transtentorial herniation. We have tested the hypothesis that decompressive hemicraniectomy for massive nondominant cerebral infarction is lifesaving in a series of 14 patients presenting with right hemispheric infarction and clinical signs of uncal herniation and impending death. We have further analyzed, in prospective follow-up examinations, the levels of physical, psychiatric, and social disabilities in these patients. METHODS: The methods used included retrospective analysis to determine rates of immediate mortality and morbidity after surgical intervention. Prospective follow-up data were obtained to determine the level of recovery in surviving patients after 1 year. Standardized measures of outcome to assess physical, psychiatric, and social recovery included the Barthel Index, Zung Depression Scale, and Reintegration to Normal Living Index. RESULTS: With decompressive hemicraniectomy, we were able to prevent death secondary to transtentorial herniation in all cases; 11 patients experienced long-term survival after the procedure, and three deaths were related to non-neurological causes. We observed that 8 of the 11 surviving patients were at home, were functioning with minimal to moderate assistance, and had Barthel scores greater than 60. The remaining three patients were severely disabled. Seven of the 11 survivors were able to walk at 1 year after undergoing the procedure. Depression and failure to reintegrate socially were experienced by most patients. CONCLUSION: This series confirms the lifesaving nature of hemicraniectomy in patients deteriorating because of cerebral edema after infarction. In patients younger than 50 years, recovery to a state of near-independence is possible.

Activities of Daily Living↗
PubMed1996

An uncertain role for p53 gene alterations in human prostate cancers.

Inactivation of the p53 gene has been implicated in prostate cancer progression. To determine the role of p53 inactivation in the progression of clinical prostatic carcinomas, we assessed 67 tumors derived from patients with clinically localized disease for chromosome 17p and p53 gene allelic loss, p53 gene mutations using single-strand conformational polymorphism and direct sequencing, and p53 protein expression using immunohistochemical staining. Of 55 informative tumors, 10 demonstrated loss of 17p or the p53 gene; however, only a single tumor had a mutation in its remaining p53 allele. Significant p53 overexpression was observed in 2 of 38 tumors, and 9 others had faint staining of a few nuclei ( < 1%). p53 overexpression occurred in no informative tumor with allelic loss or mutation. In a 1-7-year follow-up, positive immunohistochemical staining did not confer an increased risk of recurrence (risk of recurrence, 0.86, P = 0.78), whereas allelic loss of chromosome 17p appeared to be highly correlated with recurrence (risk of recurrence, 3.7, P = 0.003). In an unrelated group of 42 patients with metastatic prostate cancer, p53 overexpression was found in 26 tumors (62%), and 15(36%) had high grade staining. Neither the presence nor the degree of expression correlated with time to progression or time to death. This series suggests that p53 gene inactivation is rare in primary prostatic tumors, not essential to the development of prostate cancer metastases, and of limited use as a prognostic marker in patients with primary or metastatic disease. Another gene or genes on chromosome 17p may be involved in prostate cancer progression.

Base Sequence↗
PubMed1996

Temporary vessel occlusion for aneurysm surgery: risk factors for stroke in patients protected by induced hypothermia and hypertension and intravenous mannitol administration.

Temporary vessel occlusion is an effective technique used by microvascular surgeons to facilitate dissection and permanent clipping of cerebral aneurysms; however, several questions remain regarding the overall safety of this technique. To identify technical and patient-specific risk factors for perioperative stroke, the authors examined a series of patients in whom induced hypertension and mild hypothermia and intravenous mannitol administration were used as protection during temporary vessel occlusion for aneurysm clipping. The study comprises a nonconcurrent prospective analysis of 132 consecutive aneurysm clippings performed with the aid of temporary vascular occlusion and a specific antiischemic anesthetic protocol at the Massachusetts General Hospital from 1991 to 1993. Factors studied included duration of the temporary clip application, number of occlusive episodes, patient age and neurological status, presence of preoperative subarachnoid hemorrhage (SAH), and intraoperative aneurysm rupture ("forced" temporary clipping), as well as whether proximal vessel occlusion or complete aneurysm trapping was used. In a univariate analysis, patient age, intraoperative aneurysm rupture, temporary clipping lasting more than 20 minutes, clipping between the 4th and 10th day after SAH, and multiple clipping episodes were all significantly associated with stroke outcome. Multivariate logistic regression revealed that intraoperative aneurysm rupture (relative risk 5.6, p = 0.02) and a duration of temporary clip application that lasted more than 20 minutes (relative risk 9.4, p = 0.04) were independently associated with stroke outcome. Overall, 5.2% of the patients had postoperative clinical strokes. Based on their findings the authors conclude that temporary clipping is a safe adjunct to aneurysm surgery, particularly when the duration of clipping is short.

Adult↗
PubMed1996

Diagnosis of suspected intracranial metastases. Role of direct tissue examination.

Accurate histologic diagnosis is often critical to the appropriate choice of treatment of patients suspected of harboring brain metastases. In most cases, frame based stereotactic biopsy can provide an accurate histologic diagnosis with minimal risk of morbidity. In addition, newer modalities allow for efficient coupling of stereotactic biopsy with treatment in a single session. These include frameless stereotactic systems that facilitate the combination of open biopsy and resection as well as biopsy procedures that are combined with focal interstitial or external beam irradiation. These techniques provide increasingly convenient and effective means of achieving both diagnosis and treatment of cerebral metastases.

Aged↗
PubMed1995

Main routes of plasma lactate carbon disposal in the midgestation fetal lamb.

The turnover rates of plasma lactate, normalized for O2 consumption rate, are higher in the fetus than in the adult. This occurs despite very low rates of fetal gluconeogenesis which preclude the recycling of lactate carbon into glucose. In an effort to establish the main routes of disposal of fetal plasma lactate, 12 midgestation ovine fetuses (age 74 +/- 1 days) were infused intravenously at constant rate with L-[U-14C]lactate for a 4-hour period. At the end of the infusion, the amounts of 14C retained by the fetus and by the placenta, and the distribution of the retained 14C in free and protein-bound amino acids and in lipids were measured. Of the total 14C infused, 17.0 +/- 1.4% was recovered in the placenta, 4.0 +/- 0.3% in the fetal liver, and 15.0 +/- 0.8% in the extrahepatic fetal tissues. Of the retained radioactive carbon, 45-57% was recovered in the free and protein-bound amino acid fractions and 11-17% in the lipid fractions. Approximately 90% of the 14C in the free amino acid fractions was present as glutamate/glutamine, serine, glycine, and alanine carbon. In conjunction with data on fetal CO2 production from lactate carbon, these results demonstrate that the main routes of fetal lactate disposal are oxidation and synthesis of nonessential amino acids and lipids.

Amino Acids↗
PubMed1994

Increased nucleated erythrocytes in an infant with congenital hyperinsulinism.

A markedly elevated peripheral nucleated erythrocyte count is reported in a term nonmacrosomic infant with congenital hyperinsulinism born to a nondiabetic mother. With control of hypoglycemia and hyperinsulinism, the count declined to normal. A relationship of hyperinsulinism and erythropoiesis, not related to fetal hypoxemia, is considered.

Diazoxide↗
PubMed1994

Placental and fetal serine fluxes at midgestation in the fetal lamb.

Plasma serine disposal rate (DR), decarboxylation, and conversion to fetal plasma glycine by the placenta were measured in six fetal lambs at 72 +/- 1 days gestation. L-[1-13C]serine, L-[U-14C]serine, and 3H2O were infused over 3 h into the fetal circulation, the latter for measurement of uterine and umbilical blood flow. The fetal plasma serine DR was 8.7 +/- 1.0 mumol/min or 61.8 +/- 4 mumol.min-1.kg fetus-1. Approximately 90% of the DR represented placental uptake of fetal serine. There was no detectable release of fetal serine into the maternal circulation. The fetal arterial plasma glycine-to-serine enrichment ratio was approximately 0.30. The conversion rate of fetal serine to fetal plasma glycine by the placenta was 5.8 +/- 0.7% of the serine DR. Fetal and placental CO2 production from fetal plasma serine carbon was 1.9 +/- 0.4 and 1.2 +/- 0.4 mumol/min, respectively. Thus, at midgestation, there is a rapid fetoplacental serine exchange that constitutes most of the fetal plasma serine turnover. Placental conversion of serine to fetal glycine and serine oxidation together account for only 10% of the placental uptake of fetal serine.

Animals↗