Search PubMed⌕ Search

Biomedical subjects

R Ruiz

Publications and source records attributed to R Ruiz.

At least 145 records · Page 8Linked to original sources

Electrocardiographic monitoring during coloscopy.

Electrocardiographic abnormalities were observed in 15 of 23 patients (65%), five with known heart disease, who were monitored for one hour prior to, during and for one hour after coloscopy. In one patient, ischemic S-T depression, 2 mm. below the resting level, persisted during the one hour following coloscopy. In all other patients, the electrocariographic abnormalities disappeared before the end of the monitoring period.

Adult↗

Grammatic representation of beat sequences for fuzzy arrhythmia diagnosis.

The final stage of a system for automatic monitoring of cardiac arrhythmias is the diagnosis of the rhythm or arrhythmia present in the patient during the monitoring process. In this paper we approach the detection process by means of the analysis of the electrocardiographic signal (ECG) on a surface lead produced by those arrhythmias which can be recognized by identifying specific beat sequences and taking into account contextual information, mainly rhythm information. We have developed a diagnosis process for arrhythmias which uses a fuzzy classification of beats according to their etiology or focus of origin. The process we describe permits a more adequate consideration by the user of the arrhythmias diagnosed by the system, mainly in those cases in which the information derived from ECG analysis is not determinant.

Arrhythmias, Cardiac↗

[Role of flexible sigmoidoscopy in the early detection of colorectal tumors].

In a large endoscopic population screening study for colo-rectal polyps and cancer among 2,080 average-risk asymptomatic or with minor GI symptoms, adults of both sex, average age 56.2, were submitted to flexible sigmoidoscopy 60 cm as part of a preventive medical checkup. Procedure was very effective: 349 polyps were detected in 276 patients, with a total polyp incidence of 13.3%. In 174, more than 60% of such cases, endoscopic polypectomy was performed: 118 were tubular benign adenomas, 57 hyperplastic, 7 mixed types adenomas, 3 carcinomas in situ Dukes A, 2 villous adenomas one of them malignant, one leiomyoma and one rectal carcinoid. All in situ malignant polyps were removed endoscopically with excellent results. There was a high incidence of polyps (13.04%) in group aged 40-49, therefore changes on criteria for initiating routine flexible sigmoidoscopy must be considered. FOB tests (guaiac) showed a very low specific rate for diagnosis since only 24 out of 276 polyps bearing patients showed positive results, probably due to the fact that most polyps were non-ulcerating and small lesions. One third of the total polyps were out of the reach of the rigid scope and this procedure should be excluded in all screening programs of this type. Endoscopic polypectomy should be always an early procedure. In order to decrease the number of nondetected right side colonic lesions, non accessible to the 60 cm flexible scope, at time of polypectomy a simultaneous colonoscopy should be performed.(ABSTRACT TRUNCATED AT 250 WORDS)

Age Factors↗

[Hypotension induced by sodium nitroprusside administered via an automatic-adaptive dose regulating system. Experimental development].

Sodium nitroprusside (NPS) is a potent vasodilator which is frequently administered for the control of arterial blood pressure and peripheral resistances. Manual regulation of the dose is difficult and requires a permanent surveillance of patients under treatment. Several attempts have been made to develop an automatized system able to safely control the dose of the drug in clinical practice. However, since now the results have not been completely satisfactory. The aim of our study was to develop of a new automatic-adaptative system able to continuously control the dose of NPS. The system consists of a high precision infusion pump controlled by a microprocessor. Arterial blood pressure is continuously monitorized and according to its values NPS is automatically regulated to maintain blood pressure within a preselected range. A control "fuzzy logic" algorithm was used. We have assessed the efficacy, adaptability, and safeness of the system. The system was tested in 15 mongrel dogs. The protocol was divided into two parts. During the first part a 25% to 30% reduction in blood pressure from baseline values lasting for a period of 4 hours was attempted. The second part was devoted to test the adaptability of the control unit during induced unstable hemodynamic situations. Group I dogs were subjected to volume overload. Group II were treated with noradrenaline to increase blood pressure, and group III underwent a venous bleeding to produce arterial hypotension. Control of arterial blood pressure was achieved after a minimum of 5 min and a maximum of 19 min (mean values = 13.3 min).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

[Giant diverticulum of the sigmoid: A report on one case and review of the literature (author's transl)].

The authors report a case of giant diverticulum of the sigmoid and review the approximately forty cases published in the literature. Clinical manifestations can be either an acute abdominal syndrome of symptoms of a chronic disease. Radiological appearances are usually characteristic: the giant diverticulum is located in the sigmoid, though in one case it arose from the transverse colon. An opaque image was noted in 15 of the patients following barium meal examination, and the lesion was associated with diverticulosis of the colon in every case. Apart from 4 cases, histological appearances were also typical: the colon wall is composed of fibrous tissue which has replaced the normal layers, and the neck of the giant diverticulum is always in the antimesenteric position.

Aged↗