Cocaine-abusing parturients undergoing cesarean section. A cohort study.

BACKGROUND: Cocaine use in the United States is prevalent among pregnant women from inner city neighborhoods. To determine the anesthetic implications of cocaine use in parturients undergoing cesarean section delivery, the authors conducted a cohort study. METHODS: One thousand nine hundred seven women presenting for prenatal care were interviewed regarding substance abuse. Urine was analyzed for benzoylecgonine, tetrahydracannabinol, benzodiazepines, and opioids. Next all parturients who underwent cesarean section delivery were identified and their records reviewed for anesthetic and obstetric outcomes. RESULTS: Among the 51 women who were classified as cocaine abusers, the most frequent reasons for cesarean section were fetal distress (48%) and abruptio placenta (21%). In a multivariate model, cocaine abuse before delivery was shown to be an independent predictor of preoperative diastolic hypertension (F = 10.6, P = 0.01). Similarly, univariate analysis showed that immediately after intubation, diastolic blood pressure was significantly higher among parturients who used cocaine (99 +/- 13 mmHg v. 87 +/- 18 mmHg; P = 0.02). In contrast, epidural anesthesia was associated with hypotension significantly more often among cocaine-abusing parturients (44% vs. 10%; P = 0.04). A higher rate of perioperative wheezing was reported among patients who abused cocaine (16% vs. 6%; relative risk = 2.7); this finding, however, did not persist in multivariate analysis. Operative blood loss was similar in all groups (P = NS), and no ventricular dysrhythmias or cerebrovascular or coronary ischemic episodes were reported in any of the parturients. CONCLUSIONS: Although cocaine-abusing parturients are at higher risk for interim peripartum events such as hypertension, hypotension, and wheezing episodes, there is no significant increase in rates of maternal morbidity or death.

Parental presence during induction of anaesthesia: practice differences between the United States and Great Britain.

A questionnaire was sent to 1353 paediatric anaesthetists in Great Britain and the United States. Nineteen questions were asked about attitudes toward parental presence during induction of anaesthesia and the prevalence of such practice. Overall, respondents from Great Britain support parental presence more than the United States respondents. For example, 82% of the Great Britain respondents, vs 64% of the United States respondents thought that parental presence during induction decreases the anxiety (P = 0.001) and increases the cooperation of the child (P = 0.001). Most United States respondents (58%) allow parental presence in less than 5% of their cases, but most Great Britain respondents (84%) allow parental presence in more than 75% of their cases. We conclude that in contrast to the respondents from Great Britain, the majority of the United States sample does not feel that parental presence is useful and so does not routinely use this technique in their practice.

Anti-B4-blocked ricin synergizes with doxorubicin and etoposide on multidrug-resistant and drug-sensitive tumors.

Anti-B4-blocked ricin (anti-B4-bR) is an immunotoxin directed against CD19-positive cells that is currently being tested in several B-cell leukemia/lymphoma clinical trials. To explore the possibility of using anti-B4-bR in combination with chemotherapy protocols, we investigated the in vitro and in vivo cytotoxic effects of combining it with doxorubicin or etoposide using the lymphoma cell line Namalwa and a P-glycoprotein-expressing cell line, Namalwa/mdr-1, obtained by retroviral infection of Namalwa cells with the mdr-1 gene. Namalwa/mdr-1 cells were slightly more sensitive to anti-B4-bR than Namalwa cells; IC37 values were approximately 4 pmol/L and 8 pmol/L, respectively. When anti-B4-bR was combined simultaneously with doxorubicin or etoposide, additive to supra-additive killing of Namalwa and Namalwa/mdr-1 cells was observed. In xenografts of Namalwa/mdr-1 cells in severe combined immunodeficiency (SCID) mice, doxorubicin and etoposide at their maximum tolerated doses (3 mg/kg x 3 or 15 mg/kg x 3) showed no therapeutic effect. However, treatment with 5 daily bolus injections of anti-B4-bR (50 micrograms/kg) followed by treatment with doxorubicin or etoposide significantly increased the life span of the mice by 129% and 115%, respectively. After treatment with anti-B4-bR, the Namalwa/mdr-1 population expressed lower levels of P-glycoprotein, and this decrease may account for the synergistic action of the drug combinations. These results suggest that anti-B4-bR could be used to good effect in combination with current treatment regimens and further hint at a promising role for this immunotoxin in treatment of disease at the minimal residual disease stage, where cells may be resistant to chemotherapy.

Anti-B4-blocked ricin immunotoxin shows therapeutic efficacy in four different SCID mouse tumor models.

Anti-CD19 monoclonal antibody anti-B4 (IgG1) conjugated to the novel toxin-blocked ricin forms a potent immunotoxin, anti-B4-blocked ricin, that kills greater than 4.5 logs of CD19-positive cells in vitro after a 24-h exposure to a conjugate concentration of 5 x 10(-9) M (1.11 micrograms/ml). The efficacy of anti-B4-blocked ricin in vivo was assessed in survival models of SCID mice bearing either a human B-cell lymphoma (Namalwa), a human non-T and non-B acute lymphoblastic leukemia (Nalm-6), or a murine B-cell lymphoma transfected with the human CD19 gene (300B4). In one model, 5 x 10(7) tumor cells were injected i.p., and 1 h later the mice were treated with i.v. bolus injections of anti-B4-blocked ricin at 100 micrograms/kg/day for 5 days. Controls included similar treatment with anti-B4 antibody (72 micrograms/kg/day or 2 mg/kg/day for 5 days) alone or with the isotype-matched nonspecific immunotoxin, N901-blocked ricin (100 micrograms/kg/day). In a second model, 4 x 10(6) tumor cells were injected i.v., and 7 days later mice were treated i.v. as above. Anti-B4-blocked ricin showed efficacy by killing in vivo up to 3 logs of tumor cells, which was manifested in significant prolongation of the life of the treated animals. Only very limited or no effects were observed in animals treated with either anti-B4 antibody alone or N901-blocked ricin control conjugate. The concentration of anti-B4-blocked ricin in the blood of animals was 150 ng/ml after the first i.v. injection and about 800 ng/ml following the fifth injection of conjugate. This increase may be due to damage to the reticuloendothelial system by anti-B4-blocked ricin, since the rate of clearance of carbon from blood also decreased 5-fold after five injections as compared to the rate after only one injection. These studies indicate that anti-B4-blocked ricin has the potential to increase survival times of hosts with malignant disease.

Olfactory neuroblastoma. Cytodiagnostic features in a case with ultrastructural and immunohistochemical correlation.

In a case of olfactory neuroblastoma, originally misdiagnosed as an undifferentiated carcinoma, cytologic examination of material scraped from the superior nasal vault revealed tumor cells suggestive of neuroblastoma. The most significant cytodiagnostic feature was the presence of a fibrillary cytoplasm with ill-defined borders. Also noteworthy were the smudged hyperchromatic nuclei and structures resembling rosettes or pseudorosettes. The diagnosis was confirmed by electron microscopy, which revealed the presence of dense-core neurosecretory granules, clear vesicles, neurotubules and neurofilaments, and by immunohistochemistry, which showed positive staining for neuron-specific enolase but negative staining for keratin and glial fibrillary acidic protein. Since olfactory neuroblastoma has a relatively good prognosis and aggressive surgical resection may be curative, it is important that this tumor be distinguished from other small cell malignancies arising in the nasal cavity. The present case shows that the diagnosis can be made by the cytologic examination of scrapings from the tumor.