Biomedical subjects

R G Hahn

Publications and source records attributed to R G Hahn.

At least 199 records · Page 11Linked to original sources

PubMed1989

Complete responses and long-term survivals after systemic chemotherapy for patients with advanced malignant melanoma.

Five hundred three patients with advanced malignant melanoma were exposed to a number of clinical investigative chemotherapeutic regimens between 1971 and 1984 in an effort to assess the clinical activity of these regimens in this disease. Of the 503 patients participating in the studies, ten patients experienced a complete response. However, only three of these patients survived more than 5 years. Of this group of 503 patients, seven additional patients who did not experience a complete response survived more than five years. Of the ten patients surviving more than 5 years, two had immediate progression after institution of investigative regimens, whereas five remained stable for brief periods of time before progressive metastatic disease. Three patients experienced a complete response. It appeared that systemic therapeutic interventions in these trials were conspicuously ineffective for this large group of patients. A few long-term survivors attest to the capricious nature of this neoplasm and its association with likely spontaneous regressions. Although these long-term survivors did survive after institution of systemic chemotherapy, it is likely that this survival was related temporally, but perhaps not causally, to the institution of treatment.

Adult↗

PubMed1989

Phase II study of N-methylformamide, spirogermanium, and 4-demethoxydaunorubicin in the treatment of non-small cell lung cancer (EST 3583): an Eastern Cooperative Oncology Group study.

One hundred forty-four patients with non-small cell lung cancer, the majority (72%) of whom had received previous chemotherapy, were evaluable in this randomized phase II study of N-methylformamide (N-MF), spirogermanium, and 4-demethoxydaunorubicin. There were two partial responses, one each with spirogermanium and 4-demethoxydaunorubicin. There were eight life-threatening complications (mostly hematologic) and two lethal complications (N-MF, hematologic; 4-demethoxydaunorubicin, gastrointestinal). The overall survival ranged from 9 days to 533 days with a median of 17.6 weeks. The following factors were associated with poor survival: Poor initial performance status, prior weight loss, presence of liver or subcutaneous metastases.

Aged↗

PubMed1989

Compliance considerations with estrogen replacement: withdrawal bleeding and other factors.

Withdrawal bleeding and other side effects such as edema, bloating, premenstrual irritability, lower abdominal cramps, dysmenorrhea, and breast tenderness limit compliance with hormonal replacement therapy. Although many of these troublesome side effects can be managed by adjusting the dose or changing the source of the estrogen or progestin components, postmenopausal women view withdrawal bleeding as the most negative factor influencing their decision to use hormonal replacement therapy. Additionally, the potential link between postmenopausal estrogen use and subsequent endometrial hyperplasia and cancer concerns potential users. Cyclic progestins protect the endometrium from hyperplastic changes but may not prevent withdrawal bleeding. Both patient and physician education, including the nature of menopause and the protective role of estrogens in osteoporosis and cardiovascular disease, are critical to improving compliance with hormonal replacement therapy.

Estrogen Replacement Therapy↗

PubMed1989

Intravenous infusion of irrigating fluids containing glycine or mannitol with and without ethanol.

Irrigating fluids consisting of 5% mannitol, 3% mannitol + 1% ethanol, 2.2% glycine and 1.5% glycine + 1% ethanol in water were given by intravenous infusion to seven healthy volunteers at a constant rate of 50 ml./min. over 20 min. The irrigants containing glycine produced hyperkalemia and usually prickling and burning skin sensations and slight nausea. The severity of the symptoms apparently correlated to the blood ammonia level, which increased significantly after the glycine but not after the mannitol infusions. With 5% mannitol, there was a pronounced transient increase of the blood volume and a prolonged hyponatremia. There were no differences between the irrigants in respect to their effects on blood pressure and urine excretion. Ethanol caused no adverse effects and allowed the fluid supplementation to be followed by expired breath tests.

Adult↗

PubMed1989

Vasopressin responses during transurethral resection of the prostate.

The serum vasopressin (S-AVP) concentration, serum sodium concentration and osmolality, central venous pressure and fluid balance were measured during 10-min periods in 32 patients undergoing transurethral resection of the prostate. Concentration of S-AVP was unaffected by uncomplicated resection; irrigant absorption resulted in immediate increase in S-AVP concentration, but this increase could not explain the hypertension that occurred in some patients with absorption; a sudden decrease in the systolic arterial pressure was followed by a marked increase in S-AVP concentration; and extensive blood loss did not stimulate release of AVP, provided there was no associated arterial hypotension.

Aged↗

PubMed1989

Vasopressin and amino acid concentrations in serum following absorption of irrigating fluid containing glycine and ethanol.

Absorption of glycine solution during transurethral resection of the prostate (TURP) changes the serum concentrations of most non-essential amino acids and inhibits diuresis by stimulating release of vasopressin. Ethanol was used as a marker to detect the absorption of irrigant. Measurements of the serum concentrations of vasopressin and amino acids were made in eight patients with absorption volumes from 427 to 1906 ml. Ethanol did not alleviate the vasopressin response to glycine absorption, but changes in the amino acid concentrations in serum became less pronounced than when glycine alone was used.

Absorption↗

PubMed1989

Early detection of the TUR syndrome by marking the irrigating fluid with 1% ethanol.

The ethanol concentration in the expired breath (EB-ethanol), the volumetric fluid balance and the serum sodium concentration were measured in the course of 60 transurethral resections of the prostate in which the irrigating fluid was 1.5% glycine + 1% ethanol. Measurement of EB-ethanol indicated absorption of irrigant at a rate of more than 150 ml in 10 min, as measured volumetrically. There was a significant direct linear relationship between EB-ethanol and the cumulative volume of irrigant absorbed (R2 = 0.83); this correlation was stronger when the duration of absorption was taken into account (R2 = 0.90). EB-ethanol was inversely related to the overall change in the serum sodium concentration during the operation (R2 = 0.88). Symptoms that are recognized components of the TUR syndrome developed in 8 of the 13 patients absorbing more than 11 of irrigant, while the ethanol exerted no adverse effects. The results of the study indicate that 1% ethanol is a suitable marker for monitoring irrigant absorption by means of the expired breath test in routine transurethral surgery. At this concentration the sensitivity of the test is adequate for detecting absorption, while the ethanol is less toxic than the irrigant fluid itself.

Absorption↗

PubMed1989

Estimating allowable blood loss with correction for variations in blood volume.

All the theoretical relationships between blood loss and change in haematocrit used for calculating the allowable pre-transfusion blood loss assume a strictly normovolaemic situation. In this study a formula was derived in which account was taken of the variation in blood volume. The formula was based on clinical data. Measurements of the blood loss, the blood haemoglobin concentration and the haematocrit (HCT) were performed on 230 occasions in the course of 35 transurethral prostatic resections. The change in blood volume was estimated by the haemoglobin dilution method and the value so obtained was compared to both the measured haematocrit and the theoretical value that would presumably have been recorded if there had been no change in blood volume. The relationship established from these comparisons was: blood loss = preoperative blood volume x [In preop HCT - In postop HCT (1 + 0.15 x blood volume change)].

Aged↗

PubMed1989

Influence of the fluid balance on the cortisol and glucose responses to transurethral prostatic surgery.

The serum cortisol and blood glucose concentrations were followed for up to 2 h after 35 transurethral prostatic resections performed under epidural anaesthesia. No significant variation in either of these levels was recorded in connection with the seven operations during which there was no disturbance of the fluid balance, or the seven where there was elevation in the central venous pressure indicative of intravenous fluid overload. In contrast, both the serum cortisol and the blood glucose level showed a significant increase in the nine patients with a blood loss of more than 800 ml, and in the nine recording absorption of irrigant in excess of 300 ml and immediate development of hyponatraemia. On the other hand, this response did not occur in the three patients with irrigant absorption where hyponatraemia developed with a delay of at least 20 min. These results suggest that the effect of surgery on the serum cortisol and blood glucose levels may be modified by disturbances of the fluid balance developing in the course of the operation.

Absorption↗

PubMed1989

Acid phosphatase levels in serum during transurethral prostatectomy.

Serum prostatic acid phosphatase (S-PAP), serum electrolytes, blood loss and volume of irrigating fluid absorbed were measured during 10-min periods in the course of 35 transurethral prostatic resections. Elevation of the S-PAP concentration occurred in association with a large blood loss, with absorption of irrigant followed immediately by hyponatraemia, and with a sudden drop in systolic blood pressure. The volume of blood lost during irrigant absorption was the most important index of the S-PAP level. A model for the transfer of PAP to the circulation during TURP is presented.

Acid Phosphatase↗

PubMed1989

Glycine irrigation and urinary oxalate excretion.

The short-term effect of glycine supplementation on urinary oxalate excretion was studied. An intravenous infusion of 1 litre of a solution of 2.2% glycine, 1.5% glycine + 1% ethanol or 5% mannitol (control) was given on 13 occasions to 5 healthy volunteers. Glycine irrigation was used in 9 patients undergoing transurethral prostatic resection and the absorption of irrigant was measured volumetrically (range 0-2.71). The results suggest that glycine irrigation in transurethral prostatic surgery does not raise the urinary oxalate level in the early post-operative period.

Absorption↗

PubMed1989

Dilution of blood proteins due to irrigant absorption in transurethral prostatic resection.

The serum concentrations of albumin, transferrin, IgG, IgM and sodium, the blood haemoglobin concentration (B-Hb) and the blood loss were determined for 10-min periods in the course of 16 transurethral prostatic resections in which irrigant absorption of between 0.5 and 2.8 I had been measured volumetrically. The concentrations during resection, expressed as a percentage of those recorded just before induction of anaesthesia, were: B-Hb 89.2%, S-albumin 81.0%, S-transferrin 78.4%, S-IgG 81.0%, S-IgM 80.5% and S-Na 96.5%. The blood loss was the most important predictor of the decrease in B-Hb. The dilution of serum proteins was primarily due to hydration from crystalloid fluid given intravenously and from absorbed irrigating fluid; the most specific indicator of the degree of irrigant absorption was the serum sodium level.

Aged↗

PubMed1989

Monitoring irrigating fluid absorption during transurethral resection of the prostate (TURP); a comparison between 1 and 2% ethanol as a tracer.

In a series of 35 transurethral resections of the prostate 1% ethanol was compared to 2% ethanol as a marker of the irrigating fluid. The ethanol concentration in the expired breath of the patient (EB-ethanol) correlated significantly to the irrigant absorption, as measured volumetrically, and to the change in the serum sodium concentration at 10-min intervals during the operation. The pattern of changes in EB-ethanol indicated whether the main part of the absorption entered through the intravenous or the extravascular route. With 1% ethanol added to the irrigating solution the absorption of 100-150 ml in 10 min could readily be detected. The sensitivity was twice as great with 2% ethanol; however, 1% ethanol is sufficient for routine procedures as it permits absorption to be detected long before it is large enough to produce a TUR syndrome. Monitoring ethanol in the expired breath provides the surgeon with an instrument to check that preventive steps against further absorption are effective.

Aged↗

PubMed1988

Phase I study of difluoromethylornithine in combination with recombinant alpha 2a-interferon.

24 patients with advanced, histologically proven cancer were treated with difluoromethylornithine 2.25 g/m2 orally every 6 h for the first 7 days of each 4-week treatment cycle. These patients also received daily i.m. doses of recombinant human alpha 2a-interferon (IFN) on Days 3 through 7 of each cycle. IFN doses of 3, 6, 12, 24, 36, and 48 X 10(6) units/m2 have been studied utilizing three patients at each daily dose level. Three additional patients have been observed at each of the two highest doses for better toxicity definition. This combination produced slight transient declines in leukocyte and platelet counts and transient rises in serum aspartate aminotransferase; however, these changes were no more pronounced at the higher IFN doses than at daily doses of 6 X 10(6) units/m2. Mild nausea and vomiting occurred in most patients and mild diarrhea also was common at all IFN dose levels. Chills, fever, myalgia, lethargy and fatigue, and anorexia were also observed at all IFN doses; however, lethargy and fatigue (lassitude) seemed to be the major factor which limited patient tolerance of IFN to 48 X 10(6) units/m2 daily. No ototoxicity was identified clinically or audiometrically and no life-threatening toxicity has occurred. Initial Phase II studies in melanoma are currently in progress.

Adult↗

PubMed1988

Chemotherapy of malignant hepatomas with sequential intraarterial doxorubicin and systemic 5-fluorouracil and semustine.

Twenty patients with malignant hepatoma were treated with sequential intraarterial doxorubicin (72-hour continuous infusion) followed by systemic 5-fluorouracil (5-FU) and semustine (methyl CCNU). Objective tumor responses were seen in three patients (15%). The durations of response were 6, 19, and 27+ months, respectively. Median patient survival was 7 months. A variety of problems were encountered with the use of transcutaneous angiographic catheters for doxorubicin administration, including inability to adequately perfuse the liver, sepsis, and catheter dislodgement during chemotherapy infusion. Although some patients experienced palliation of reasonable duration, we do not believe that the overall results warrant further studies of this regimen.

Adult↗

PubMed1988

An evaluation of recombinant leukocyte A interferon with aspirin in patients with metastatic renal cell cancer.

The authors designed a clinical trial to assess the impact of aspirin (ASA) (600 mg four times daily) on the constitutional sequelae of recombinant leukocyte A interferon (IFN-alpha 2A), 20 X 10(6) U/m2 thrice weekly, in 29 patients with advanced renal cell cancer (RCC). Aspirin provided no meaningful amelioration of side effects compared to our prior experience of IFN-alpha 2A alone. Interestingly, the objective response rate of 34% (10/29) was considerably higher than the 15% recently reported from an aggregate of 344 patients participating in 14 prospective clinical trials. In light of small numbers, subtle selection biases, and the well-recognized hazards of retrospective analyses, currently it is unclear if the apparent therapeutic advantage from ASA plus IFN-alpha 2A reflects chance occurrence or therapeutic potentiation from ASA. A randomized trial is planned to determine if ASA may have enhanced the efficacy of IFN-alpha 2A in patients with advanced RCC.

Anorexia↗

PubMed1988

Phase II trials of 5-day vinblastine infusion (NSC 49842), L-alanosine (NSC 153353), acivicin (NSC 163501), and aminothiadiazole (NSC 4728) in patients with recurrent or metastatic renal cell carcinoma.

One hundred and forty-four evaluable patients with recurrent or metastatic renal cell carcinoma (RCC) were treated with vinblastine infusion (n = 35), L-alanosine (n = 36), acivicin (n = 27), or aminothiadiazole (n = 46). Observed objective response rates of 9%, 3%, 4%, and 2%, respectively indicate that noe of these agents has significant antineoplastic activity in recurrent or metastatic RCC. Multivariate analysis of survival data suggests that initial performance status, time from initial diagnosis to study entry, and the presence or absence of lung metastases are important prognostic factors for survival. After adjustment for these factors, treatment assignment was also seen to be of prognostic value. All four treatments were generally well tolerated. There were no reports of life-threatening or lethal toxicities; however, 37% of the patients experienced severe reactions to treatment, primarily myelosuppression, anemia, neuropathies, and mucositis.

Adult↗

PubMed1988

Hallucination and visual disturbances in transurethral prostatic resection.

The successful treatment of a patient who developed the TUR syndrome is described. Glycine 2.2% in water was used as irrigating fluid. Initial symptoms were visual disturbances and hypertension. Repeated blood chemistry analyses revealed elevations in the serum concentrations of most non-essential amino acids. Later on the patient experienced vivid hallucinations.

Absorption↗