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R Rodríguez

Publications and source records attributed to R Rodríguez.

349 records · Page 20Linked to original sources

[Synergism of midazolam and propofol in the induction of anesthesia].

INTRODUCTION: The purpose of this study was to determine the possible interaction of midazolam and propofol in the induction of anesthesia. METHODS: A double-blind study of 90 ASA I-II women undergoing elective general surgery and gynecology was performed. The patients were divided into three groups of 30 patients receiving midazolam, propofol and a combination of both as the anesthesia induction agent. As a test of anesthetic induction the response to the verbal order of opening their eyes was evaluated. The dose-response curves for each group were determined by a logistic regression procedure while isobolographic analysis compared the actions of both agents separately and together. RESULTS: The ED50 in the propofol group was 1.56 mg.kg-1 and that of the midazolam group was 0.24 mg.kg-1. In the midazolam-propofol group the ED50 of midazolam was reduced approximately a quarter (0.068 mg.kg-1) when associated to the half of the ED50 of propofol anteriorly obtained. Isobolographic analysis revealed that the conjunctive action of both drugs was synergic (p = 0.04). CONCLUSIONS: Propofol potentiates the action of midazolam in anesthetic induction. Although this synergism also reduces with the association of thiopental-midazolam, the mechanism of action is not demonstrated as the same. Thiopental increases the affinity of the benzodiazepines for the GABA complex receptors which has not been described for propofol.

Adult↗

[Use of hospital services by the aged population of Mexico City].

OBJECTIVE: The purpose of this study was to determine the characteristics of hospital utilization by the elderly in three hospitals in Mexico City during 1992 and 1993. Main reason for admission, average length of stay and type of treatment received were some of the variables studied. MATERIAL AND METHODS: A random sample of 820 clinical files were selected, 308 from the Instituto Nacional de la Nutrición Salvador Zubirán (INNSZ), 189 from the Hospital General Manuel Gea González (HGMGG) and 323 from the Hospital Regional Adolfo López Mateos (HRALM). The principal reasons for admission, average days spent in the hospital and type of treatment received were identified for patients 60 years and older. Univariate and bivariate analysis was performed with hypothesis test for differences between sexes. RESULTS: Diabetes mellitus and hypertension were the principal reasons for admission length of stay varied considerably and was the longest at the INNSZ (median: 12 days) and the shortest at the HRALM (median: 8 days). Most of the patients were admitted through the emergency service, except in the INNSZ where most came for ambulatory visit.

Aged↗

Prognostic significance of pathological response of primary tumor and metastatic axillary lymph nodes after neoadjuvant chemotherapy for locally advanced breast carcinoma.

PURPOSE: The prognostic significance of pathological response of primary tumor and metastatic axillary lymph nodes after neoadjuvant chemotherapy was assessed in patients with noninflammatory locally advanced breast carcinoma. PATIENTS AND METHODS: Between January 1989 and April 1995, 148 consecutive patients with locally advanced breast carcinoma participated in the study. Of these, 140 fully evaluable patients (67, stage IIIA; 73, stage IIIB) were treated with three courses of 5-fluorouracil, doxorubicin, and cyclophosphamide (FAC), followed by modified radical mastectomy when technically feasible or definitive radiation therapy. The median age was 53 years (range, 26 to 75 years); 55% of patients were postmenopausal. RESULTS: Objective response was recorded in 99 of 140 patients (71%; 95% confidence interval, 63% to 79%). Complete response occurred in 11 patients (8%), and partial response occurred in 88 patients (63%). No change was recorded in 37 patients (26%), and progressive disease occurred in 4 patients (3%). One hundred and thirty-six patients underwent the planned surgery. Maximal pathological response of the primary tumor (in situ carcinoma or minimal microscopic residual tumor) was observed in 24 (18%); 112 patients (82%) presented minimal pathological response of the primary tumor (gross residual tumor). The number of metastatic axillary nodes after neoadjuvant chemotherapy was as follows: N0, 39 patients (29%); N1-N3, 35 patients (26%); > N3, 62 patients (45%). Considering the initial TNM status, 75% of the patients had decreases in tumor compartment after neoadjuvant chemotherapy. Also, 31% and 23% of patients with clinical N1 and N2, respectively, showed uninvolved axillary lymph nodes. A significant correlation was noted between pathological response of primary tumor and the number of metastatic axillary lymph nodes. Median disease-free survival was 34 months, whereas median overall survival was 66 months. Pathological responses of both primary tumor and metastatic axillary lymph nodes were strongly correlated with disease-free survival and overall survival in univariate analyses. Additionally, in a proportional hazard regression model and in an accelerated failure time model, metastatic axillary lymph nodes significantly influenced both disease-free survival and overall survival, whereas pathological response of primary tumor did so on disease-free survival only. CONCLUSION: After neoadjuvant chemotherapy, pathological responses of both primary tumor and metastatic axillary lymph nodes had a marked prognostic significance and influenced outcome for patients with locally advanced breast carcinoma. Our results suggest that maximal tumor shrinkage and sterilization of potentially involved axillary nodes may represent a major goal of neoadjuvant chemotherapy. Further studies are warranted to clarify whether these results reflect the therapeutic effect or intrinsic biologic factors of the tumor.

Adenocarcinoma↗

[Explicit and implicit memory during inhalation and intravenous anesthesia].

OBJECTIVE: Patients rarely report memory or knowledge of surgery after general anesthesia. During apparently adequate surgical anesthesia, however, information processing of high level functions, such as language comprehension and learning, can continue unconsciously. Our objective is to assess whether different anesthetic techniques (two inhalational and two intravenous) guarantee the absence of both types of memory. PATIENTS AND METHOD: One hundred patients were randomly assigned to receive the following anesthetic procedures: desflurane/N2O (group 1), isoflurane/N2O (group 2), fentanyl/N2O (group 3) and total intravenous anesthesia (group 4). A cassette with the same music was played in all cases, and an order requiring a nonverbal response was given to 15 randomly chosen patients in each group. Response was evaluated at a visit 24 to 48 hours after surgery. Fifteen patients, therefore, constituted the study group for each anesthetic procedure, and 10 patients formed the control group. We assessed the presence of explicit memory in a structured interview, and implicit memory by way of the relation between the number of times the nonverbal order was obeyed and the time of the interview. RESULTS: Explicit memory was absent in all patients. The presence of implicit memory was confirmed, however, in the isoflurane (p = 0.02) group. Significant differences between the isoflurane group and both the desflurane and total intravenous anesthesia groups (p = 0.03) were found. CONCLUSION: Explicit memory was absent with all four anesthetic techniques used in our study. Implicit memory was more difficult to inhibit, however, with isoflurane/N2O.

Adolescent↗