Head pain associated with sixth-nerve palsy: spontaneous dissection of the internal carotid artery

BACKGROUND: Iodixanol (Visipaque, Nycomed Imaging AS, Oslo, Norway) is a new non-ionic and isotonic X-ray contrast medium. OBJECTIVE: To assess its safety and efficacy for paediatric excretory urography. MATERIALS AND METHODS: A three-centre trial in which 72 patients were randomised into three parallel groups: iodixanol 270 mgI/ml, iodixanol 320 mgI/ml and iohexol 300 mgI/ml (Omnipaque, Nycomed Imaging, Oslo, Norway). Doses ranging from 1 to 3 ml/kg never exceeded 50 ml. Pulse rate and blood pressure were recorded before, during, and after the examination. Adverse events, including injection associated discomfort, were recorded during and up to 24 h after the examination. The diagnostic quality of the urograms was assessed on a four-level scale. RESULTS: No serious adverse event occurred in any of the three groups. One patient who was given iodixanol 270 mgI/ml, three who received iodixanol 320 mgI/ml, and one who received iohexol 300 mgI/ml experienced transient adverse events. More than 80 % of the urograms in all three groups were rated "good" or "excellent". CONCLUSION: Iodixanol, either 270 mgI/ml or 320 mgI/ml, is well tolerated and efficacious for excretory urography in children.     

Myelography in the dog with non-ionic contrast media at different iodine concentrations

Image quality and side effects were evaluated retrospectively in a series of 183 myelographic studies performed with two non-ionic contrast media (iohexol and iopamidol) at different concentrations. Side effects during and following the procedure were recorded. Image quality was assessed using an arbitrary scoring system and statistical analysis was performed with the cross-tabulation test (4 x 2 table) by comparing two groups receiving contrast medium at higher and lower concentrations. No significant differences in side effects were observed between the two groups but the ratings for image quality were significantly higher in the group receiving contrast medium at the higher concentration than in the group receiving the lower concentration. The results suggest that a high concentration of non-ionic contrast media can safely be used in dogs and may improve image quality.     

Molecular cloning and functional expression of a recombinant 72.5 kDa fragment of the 110 kDa regulatory subunit of smooth muscle protein phosphatase 1M

RATIONALE AND OBJECTIVES: We compared adverse reactions and image quality for hysterosalpingography (HSG) performed with ionic (diatrizoate meglumine combined with iodipamide meglumine [DM + IM]) and nonionic (iohexol) contrast media. METHODS: We performed a study of 95 patients who had HSG and were randomly selected to receive DM + IM or iohexol. Patients reported episodes of abdominal pain and other adverse reactions immediately and 24 hr after the procedure and categorized severity of symptoms on a subjective scale. Two radiologists evaluated image quality for diagnosis. RESULTS: Prevalence of abdominal pain and other reactions both immediately and 24 hr after HSG was lower in patients who received iohexol than in patients who received DM + IM. Moderate or severe abdominal pain was significantly lower in the iohexol group than in the DM + IM group (p < .05). Visualization of the uterine cavity and ampullary rugae was judged excellent with both contrast media (87% with iohexol and 92% with DM + IM). CONCLUSION: Iohexol and DM + IM are excellent contrast media for use during HSG; iohexol 300 may cause fewer episodes of more severe and prolonged abdominal pain.     

Treatment of sudden deafness apropos of 447 cases

Tibial nerve and S1 dermatome somatosensory evoked potentials (SSEPs) were recorded before and after iohexol lumbar myelography in order to evaluate possible neurotoxic effects of this contrast medium. No significant change in SSEP latencies nor amplitudes was noted after iohexol myelography, supporting the low neurotoxic profile of this contrast agent. Results were compared to those of a control group of patients before and after lumbar puncture (LP), without injection of contrast agent. In this group also no significant change in SSEP components was found, indicating that a preceding LP does not affect this electrophysiological examination.     

The influence of intrathecal fentanyl on the characteristics of subarachnoid block for caesarean section

Forty healthy parturients scheduled for elective Caesarean section were randomly allocated to receive either 0.3 ml 0.9% saline (control group, n = 20), or 15 micrograms (0.3 ml) fentanyl (treatment group, n = 20) added to 2.5 ml 0.5% hyperbaric bupivacaine given intrathecally in the sitting position. A sensory block to T4 was achieved after 6.5 min in those who received fentanyl compared to 8.0 min in the control group; this was not significantly different. The highest level of sensory block achieved in both groups was similar. Ephedrine was required earlier (p < 0.05) in those who received fentanyl but the total requirement of ephedrine intra-operatively was similar. Fentanyl significantly improved the quality of intra-operative surgical anaesthesia as none of the patients in the treatment group complained of discomfort compared with seven in the control group (p < 0.05). Similarly those in the treatment group had better comfort scores as evaluated by visual analogue score (p < 0.01). Regression of anaesthesia to T12 took longer (184 vs 156 min, p < 0.05) in those who received fentanyl but this did not affect the total requirement of morphine in the first 24 h after operation. There was no difference in the incidence of side effects in the mother and no adverse effects were detected in the baby. The results indicate that adding 15 micrograms fentanyl to hyperbaric bupivacaine for spinal anaesthesia markedly improves intra-operative anaesthesia for Caesarean section.     

Quantitative assessment of platelet function and clot structure in patients with severe coronary artery disease

RATIONALE AND OBJECTIVES: Although systemic absorption of enterically administered iohexol and its excretion in urine has been previously documented in rats with ischemic bowel, a practical and sensitive method of detecting urinary iohexol has not been available. We proposed to detect the presence of iohexol in the urine of rats with normal and ischemic bowel by use of a computed tomography (CT) number increase in the bladder with the use of CT. METHODS: Anesthetized rats (250 g) underwent either sham laparotomy (n = 6), ligation of two vascular arcades to the proximal jejunum (n = 5), ligation of six vascular arcades to the proximal jejunum (n = 6), or ligation of the superior mesenteric artery (n = 6). Rats were hydrated with saline (3.2 ml/hr intravenously). Each received a 3-ml enteric bolus of isotonic iohexol. Serial CT scans and plain film radiographs of the bladder were performed at 2, 4, and 6 hr to detect systemic absorption of contrast from the gut. Urine iohexol concentrations were measured by capillary electrophoresis. CT number and iohexol concentration were compared with evidence from plain film radiographs of bladder opacification. Intestinal ischemia was graded histologically. RESULTS: Histologic evidence of ischemia was present in all six-arcade and five of six superior mesenteric artery (SMA)-ligated animals. No animals in the control or two-arcade group showed evidence of bowel ischemia. Statistically significant increases (P < 0.05) in bladder density were demonstrated in the six-arcade and SMA-ligated groups. No statistical difference was noted between the two-arcade ligation and control groups. CONCLUSIONS: Experimental intestinal ischemia was reliably detected by bladder opacification after administration of enteric contrast. CT detection of systemic absorption of enteric iohexol was more sensitive than plain film radiographs and may be useful in the diagnosis of intestinal ischemia, although it may not be specific for ischemia.     

Comparative study of papaverine plus phentolamine versus prostaglandin E1 in erectile dysfunction

PURPOSE: We compared the efficacy and short-term adverse effects of 1 ml. 30 mg./ml. papaverine plus 0.5 mg./ml. phentolamine versus 1 ml. 30 micrograms./ml. prostaglandin E1 in patients undergoing pharmacological erection testing. MATERIALS AND METHODS: A total of 60 patients (mean age 58 years) with a history of sexual erectile dysfunction longer than 6 months was randomly classified into 6 groups to be tested 1 week apart with the 2 solutions and with placebo to evaluate erection response and short-term adverse effects. RESULTS: Of the patients tested with papaverine plus phentolamine 54% responded with erections adequate for penetration, compared to 50% of those tested with prostaglandin E1 (p > 0.05). Prolonged erection occurred in 18% of patients tested with papaverine plus phentolamine and 15% of those tested with prostaglandin E1 (p > 0.05). Pain was reported by 15 and 35% of patients, respectively (p < 0.05). CONCLUSIONS: One ml. 30 mg./ml. papaverine plus 0.5 mg./ml. phentolamine has the same efficacy and equal prolonged erection rate as 1 ml. 30 micrograms./ml. prostaglandin E1 but the latter agent induces significantly more pain.     

Clearance of iohexol, chromium-51-ethylenediaminetetraacetic acid, and creatinine for determining the glomerular filtration rate in pigs with normal renal function: comparison of different clearance techniques

RATIONALE AND OBJECTIVES: We wanted to improve determination of the glomerular filtration rate (GFR) with plasma clearance techniques because the alternative-renal clearance techniques-may involve inaccurate urine sampling or risk of urinary tract infection when bladder catheterization becomes necessary. Therefore, we compared the renal and plasma clearances of iohexol and chromium-51-ethylenediaminetetraacetic acid (51Cr-EDTA), as well as endogenous creatinine clearance, in 19 normal pigs using different techniques. METHODS: After an intravenous bolus injection of the GFR markers, 16 plasma samples were used to plot the marker concentrations versus time for 4.5 hr. Urine was collected during nine 30-min periods. Plasma clearance was calculated by dividing the dose of marker with the area under the plasma concentration curve (AUC) from the time of injection to infinity using one-compartment (ClAUC-slope) and three-compartment (ClAUC-3comp) models. The renal clearance was calculated by dividing the amount of marker excreted in the urine in a period with the AUC in the same period. This AUC was determined by integrating the total area in the period (Clren adv)--our reference method representing the "true" GFR--or by using the arithmetic mean of the plasma concentrations of the marker at the beginning and end of the urine collection period (Clren simple). Creatinine clearance was determined according to Clren simple. RESULTS: Renal clearances of iohexol and 51Cr-EDTA were significantly higher than creatinine clearance (P = .0002). There was no significant difference between the renal clearances of iohexol and 51Cr-EDTA or between their plasma clearances. The two mathematical methods of calculating the renal clearance of iohexol were highly correlated (rs = .99), as were the two methods of calculating its plasma clearance (rs = .95). Because of the extrarenal clearance of the markers, the plasma clearance methods for iohexol and 51Cr-EDTA always overestimated the true GFR. ClAUC-3comp was the method closest to the true GFR. For iohexol, the median overestimation of the GFR was higher with ClAUC-slope when early plasma samples (30-120 min) after injection of the marker were used (5.5 ml.min-1.10 kg-1) than when late samples (180-270 min) were used (4.0 ml.min-1.10 kg-1). After subtracting the median extrarenal clearances of iohexol and 51Cr-EDTA (previously determined in nephrectomized pigs) from their plasma clearances (ClAUC-3comp), the median overestimation of the true GFR was reduced from 2.0 to 1.1 ml.min-1.10 kg-1 with iohexol and from 2.1 to 1.3 ml.min-1.10 kg-1 with 51Cr-EDTA. CONCLUSION: GFR determination with plasma clearance techniques can be improved in three- and one-compartment models by taking late plasma samples and by subtracting the extrarenal plasma clearance of the species. One-compartment models can be improved by determining a correction formula in the species for the early parts of the decay curve of the plasma concentration of the marker.     

Aspirin and fraxiparine in the prevention of laser induced thrombosis in the presence of iodinated contrast media

The purpose of this study was to investigate the thromboembolic properties of ionic and nonionic contrast media in rats pretreated with aspirin and/or fraxiparine using an experimental model of laser induced thrombosis in the mesenteric microvessels of 17 groups of five male Wistar rats each. Two ionic (ioxaglate and diatrizoate) and two nonionic contrast media (iopamidol and iohexol), alone or associated with antithrombotic drugs (aspirin and/or fraxiparine) were studied. To evaluate the effects of these substances in this model, the number of laser beams needed to induce platelet thrombus formation, the number of emboli detached from the thrombus and the duration of embolization were quantified. Platelet aggregation induced by ADP, induced hemorrhagic time (IHT) and haemoglobin loss level were also determined. Both contrast media injected at 3 ml/kg caused a significant increase in the number of emboli and the duration of embolization (p<0.05). Pretreatment with aspirin and/or fraxiparine in the presence of ionic contrast media showed antithrombotic activities equal to those obtained when they were tested alone (p<0.05), while in the presence of nonionic contrast media, these drugs only neutralised the prothrombotic effects. There were no differences with the NaCl treated group (p>0.05). The ionic contrast media, and to a lesser extent the nonionic contrast medium: iohexol, inhibited platelet aggregation, while iopamidol behaved as an activator. The antithrombotic drugs tested in this study prevent the prothrombotic activities of contrast media therefore suggesting their use before radiographic procedures.     

A class of chromatin particles associated with nonhistone proteins

Unfixed nucleoproteins may be banded isopycnically in metrizamide (2(3-acetamido-5-N-methylacetamido-2,4,6-triiodobenzamido)-2-deoxy-D-glucose) according to the protein/nucleic acid ratio. Unsheared or lightly sheared chromatin bands sharply (p=1.2 g/ml); it has a protein/DNA ratio of 1.4. Chromatin sheared by sonication to approximately 350 base pairs of DNA contains two components with protein/nucleic acid ratios of approximately 1.3 (p=1,185 g/ml) and 2 (p=1.245 g/ml). When chromatin is digested exhaustively with staphylococcal nuclease, two density components are found, one with a protein/DNA ratio of 1.5 (p=1.21 g/ml), the other with a protein/DNA ratio of 2 (p=1.24 g/ml). In both instances the denser particle (p=1.24 g/ml) contains nearly all the nonhistone proteins, while both dense and light fractions contain histones in similar amounts. The base sequence complexity of DNA from the fractions is not distinguishable from that of total DNA and there is no evidence of any concentration of sequences complementary to polysomal polyadenylated RNA molecules.     

Antianginal response to once-daily diltiazem CD in patients receiving concomitant beta-blockers, long-acting nitrates, or both. Diltiazem CD Study Group

STUDY OBJECTIVE: To determine the safety and efficacy of diltiazem CD 180 mg administered once/day in patients with chronic stable angina inadequately controlled with P-blockers, long-acting nitrates, or both. DESIGN: Multicenter, randomized, double-blind, placebo-controlled, parallel-group trial. SETTING: Medical clinics in the private and academic sectors. PATIENTS: Of 172 patients, 170 completed the 2-week double-blind treatment period. INTERVENTION:. Patients received either diltiazem CD 180 mg or placebo once/day in combination with existing antianginal therapy. MEASUREMENTS AND MAIN RESULTS: The time to termination of exercise tolerance testing, 24 hours after the dose increased significantly in the diltiazem CD group (37.2 sec) compared with the placebo group (21.3 sec, p=0.0438). Time to onset of angina during exercise testing also increased (57.6 vs 35.0 sec, respectively, p=0.0324), as did time to moderate angina (37.5 vs 20.6 sec, respectively, p=0.0354). The rates of total angina attacks and of angina attacks on exertion were significantly reduced in the diltiazem CD group versus placebo (p<0.05). Significant reductions in systolic and diastolic blood pressures and heart rate-blood pressure product measured at rest, submaximum exercise, and exercise termination were observed in diltiazem CD-treated patients compared with placebo (p<0.05). The frequency of treatment-related adverse events was identical in the two groups, 15.1%. CONCLUSION: Diltiazem CD 180 mg once/day is an effective, safe, and beneficial initial dosage when added to existing antianginal therapy.     

Orbitography with a new non-ionizing water-soluble contrast medium

Metrizamide is a non-ionic water-soluble contrast medium which is isotonic with human blood and tissue fluid at a concentration of 170 mgI/ml. Retrobulbar injection of 3 ml isotonic metrizamide in the muscular conus of rabbits causes slight and inconstant cellulitis, but a similar reaction can also be found after injection of the same amount of saline. It seems probable that the introduction of fluid sufficient to cause an increase in the retrobulbar pressure can cause inflammatory changes in the orbital tissue, and that this is not always caused by the contrast medium itself. Four patients were examined by orbitography with injection of 4 ml isotonic metrizamide. There were no side effects, and the orbitograms showed contrast of good quality. Metrizamide is therefore considered very suitable for orbitography, especially in hospitals where computer-tomography is not yet available.     

Use of iohexol to quantify hemodialysis delivered and residual renal function: technical note

BACKGROUND: Classically, urea (molecular wt = 60) is used to determine the urea reduction ratio (URR) or clearance, based on volume of distribution (Kt/V). These methods are subject to many errors. The purpose of this study was to determine whether iohexol (Io; molecular wt = 821) could be used instead of urea and provide better information as well as middle molecule clearance data. METHODS: Ten hemodialysis (HD) patients were evaluated. All were dialyzed for three hours, and a single bolus of 100 ml of Io was injected immediately post-HD. For direct dialysis quantification (DDQ), the spent dialysate was collected in a drum, and urea and iodine (I) determined immediately prior to, at the end of, and 30 minutes post-HD. As routinely used, DDQ measures clearance directly rather than estimates the levels. RESULTS: Calculated Kt/V urea (1.21+/-0.05) significantly overestimated DDQ Kt/V urea (0.78+/-0.04, P < 0.001) whereas calculated and DDQ Kt/V Io were similar (1.44+/-0.10 vs. 1.36+/-0.05). The URR and iohexol reduction ratio (IoRR) were also different (0.63+/-0.02 vs. 0.69+/-0.02; P < 0.002) with a urea but not Io rebound (URR30 min 0.59+/-0.02, P < 0.05). Calculated urea clearance (C(urea)), 247+/-21 ml/min, significantly overestimated DDQ C(urea) (157+/-10 ml/min P < 0.001). Calculated CIo and DDQ CIo, however, were similar (109+/-8 vs. 104+/-7 ml/min). Total body clearance (TBC) in six anuric subjects was 2.5+/-0.3 ml/min, and in four oliguric subjects was 5.2+/-0.5 ml/min. In 10 additional patients, direct urine measurements demonstrated a non-renal clearance (NRC) of 2.97+/-0.18 ml/min, which was 4.0+/-0.3% of body wt. Use of this factor allowed an estimation of residual renal function (RRF) that accurately reflected measured RRF (1.32+/-0.53 vs. 1.42+/-0.55 ml/min) CONCLUSION: A single injection of Io can be used to determine Kt/V, RR, and RRF without rebound or the inconvenience of urine collection. It may also represent middle molecule clearance better than urea kinetics, and may serve as a superior method for determining HD delivered and dialysis adequacy.     

Intrapleural streptokinase versus urokinase in the treatment of complicated parapneumonic effusions: a prospective, double-blind study

Intrapleural administration of fibrinolytics has been shown in small numbers of patients with complicated parapneumonic effusions (CPE) and pleural empyema to be effective and relatively safe. Although streptokinase (SK) is recommended as the fibrinolytic of choice, there are no comparative studies among fibrinolytics. We therefore compared the efficacy, safety, and the cost of treatment two of the most used thrombolytics, SK and urokinase (UK). Fifty consecutive patients with CPE or empyema were randomly allocated to receive either SK (25 patients) or UK, in a double-blind fashion. All patients had inadequate drainage through chest tube (< 70 ml/24 h). Both drugs were diluted in 100 ml normal saline and were infused intrapleurally through the chest tube in a daily dose of 250,000 IU of SK or 100,000 IU of UK. The chest tube was clamped for 3 h after instillation. Response was assessed by clinical outcome, fluid drainage, chest radiography, pleural ultrasound, and/or computed tomography. Clinical and radiologic improvement was noted in all but two patients in each group, who required surgical intervention. The mean volume drained during the first 24 h after instillation was significantly increased; 380 +/- 99 ml for the SK group (p < 0.001) and 420.8 +/- 110 ml for the UK group (p < 0.001). The total volume (mean +/- SD) of fluid drained after treatment was 1,596 +/- 68 ml for the SK group, and 1,510 +/- 55 ml for the UK group (p > 0.05). The SK instillations (mean +/- SD) were 6 +/- 2.16 (range, 3 to 10) and those of UK 5.92 +/- 2.05 (range, 3 to 8). High fever as adverse reaction to SK was observed in two patients. The total cost of the drug in the UK group was two times higher than that of SK ($180 +/- 47 for SK and $320 +/- 123 for UK). The mean total hospital stay after beginning fibrinolytic therapy was 11.28 +/- 2.44 d (range, 7 to 15) for the SK group and 10.48 +/- 2.53 d (range, 6 to 18) for the UK group (p = 0.32). We conclude that intrapleural SK or UK is an effective adjunct in the management of parapneumonic effusions and may reduce the need for surgery. UK could be the thrombolytic of choice given the potentially dangerous allergic reactions to SK and relatively little higher cost of UK.     

Capillarovenous angioma of the maxillary sinus. Apropos of a case with review of the literature

Metabolic side-effects of antihypertensive drugs may increase the risk of coronary heart disease despite an adequate blood pressure reduction. Since combinations of different antihypertensive drugs are often necessary and frequently used, we performed a randomized study comparing the effects of a fixed combination of hydrochlorothiazide and sotalol (group A), or hydrochlorothiazide and captopril (group B) on blood pressure and on lipid and glucose metabolism in 40 men with essential hypertension over 1 year. Significant blood pressure reductions (p < 0.001) were achieved in both treatment groups: from 160/105 to 128/88 mmHg in group A (mean doses: hydrochlorothiazide 33 and sotalol 197 mg) and from 162/106 to 135/89 mmHg in group B (hydrochlorothiazide 33 and captopril 64 mg) after 12 months, respectively. No significant changes in body weight were observed in either treatment group. Triglycerides increased (p < 0.05) in both treatment groups (from 183 to 262 mg/dl in A, and from 160 to 196 mg/dl in B) and HDL cholesterol decreased (p < 0.001 and < 0.05) in both groups (from 45.1 to 35.7 mg/dl in A, and from 49.3 to 46.3 mg/dl in B), whereas LDL cholesterol increased significantly (p < 0.05) only in group A from 153 to 164 mg/dl. No significant changes were observed in total cholesterol nor in lipoprotein(a) concentrations in either treatment group. Fasting plasma glucose and hemoglobin A1 increased significantly (p < 0.05) only in group A after 1 year of treatment (from 91.6 to 98.0 mg/dl, and from 6.3 to 6.9%, respectively). Serum levels of creatinine and potassium decreased, and uric acid increased significantly under either combination. Our data show that the diuretic/beta-blocker combination has adverse effects on lipid and glucose metabolism after long-term therapy. The effects of the diuretic/ACE inhibitor combination on lipid metabolism are less pronounced and there are no adverse effects on glucose metabolism. However, the ACE inhibitor component could not completely counteract the metabolic effects of the diuretic. Both combinations have no effects on Lp(a). We conclude that the combination of hydrochlorothiazide with an ACE inhibitor has a better metabolic profile for the treatment of essential hypertension than the combination with a beta-blocker.     

Parkinson's disease: improved function with GM1 ganglioside treatment in a randomized placebo-controlled study

BACKGROUND/OBJECTIVE: Studies in animal models of Parkinson's disease (PD) suggest that GM1 ganglioside treatment can restore neurologic and dopaminergic function. In view of positive preclinical findings and the results of a previous open-label study demonstrating efficacy of GM1 in PD patients, this study compared effects of GM1 ganglioside and placebo on motor functions in PD patients. METHODS: Forty-five patients with mild to moderate PD were studied. The primary efficacy measure was change in the Unified Parkinson's Disease Rating Scale (UPDRS) motor score. After three independent baseline assessments, patients received IV infusion of the test drug (1,000 mg GM1 or placebo) and then self-administered either GM1 or placebo twice daily (200 mg/day, subcutaneously) for 16 weeks. Patients were examined during monthly follow-up visits. RESULTS: There was a significant difference between groups in UPDRS motor scores at 16 weeks (p=0.0001). The activities of daily living portion of the UPDRS (off-period assessment) also showed a significant effect in favor of the GM1-treated patients (p=0.04). GM1-treated patients also had significantly greater mean improvements than placebo-treated patients in performance of timed motor tests including tests of arm, hand, and foot movements, and walking. GM1 was well tolerated and no serious adverse events were reported. CONCLUSIONS: This study demonstrates that GM1 ganglioside treatment enhances neurologic function significantly in PD patients. Further study is warranted to evaluate long-term effects of GM1 in PD patients and to elucidate further the mechanisms underlying patient improvements.     

Rate of neuronal fallout in a transsynaptic cerebellar model

PURPOSE: A retrospective study was undertaken of the late adverse reactions following the injection of contrast media. The purpose was to determine whether there was a difference between non-ionic monomeric (iohexol) and non-ionic dimeric (iodixanol) contrast media in the reactions produced. MATERIAL AND METHODS: A total of 3,408 patients were sent a written questionnaire in which they were asked to confirm or deny any subjective discomfort or adverse event during a period of one hour to one week after a previous radiological examination with contrast medium. Patients who had undergone angiography (i.v. or i.a. injection) and CT (i.v. injection) were included. Objective signs of an allergy-like reaction were listed and the patients were asked to subjectively quantify any consequent discomfort. RESULTS: The compliance rate was 84%. Of the 3075 injections finally included in the study, 133 (4.3%) had resulted in contrast-medium-related adverse reactions of which 72 (2.3%) were immediate and 61 (2%) were late. Iohexol induced late reactions in 14/851 (1.7%) cases, and iodixanol in 24/1218 (2.0%) cases following i.v. injection and in 23/1006 (2.3%) cases following i.a. injection. The differences were not significant. There were no differences between the two contrast media in the subjective rating of discomfort except that the patients who had received iodixanol also had the highest individual-intensity score. No patient had been hospitalized owing to an adverse reaction and all reactions had been regarded as mild or moderate. CONCLUSION: The number of late adverse reactions was low. There was no difference in the frequency of the late adverse reactions following i.v. injection between iodixanol and iohexol. There was also no difference in the reactions between the i.a. and i.v. injections of iodixanol.     

Oxygen administration increases plasma digoxin-like substance and renal sodium excretion in chronic hypoxic patients

Despite the absence of cardiac or renal pathologies, edema and mild hyponatremia may often occur in patients affected by chronic obstructive pulmonary disease (COPD). Therefore, it has been suggested that hypoxia may influence the release of different hormones regulating renal sodium handling. To evaluate the effect of hyperoxia and O2 removal on plasma digitalis-like substance (DLS) levels, 9 patients affected by COPD and 7 normal subjects were studied. After 1 h in supine position, O2 was administered for 3 h by a tight-fitting face-mask. Blood samples for plasma DLS were taken at time 0, 60, 180 min and then for 3 h after O2 removal. In normal subjects, plasma DLS did not vary after O2 administration (from basal values of 162.25 +/- 8.59 to 107.75 +/- 6.65 pg/ml at 180 min; NS), and O2 removal (143.7 +/- 16.87 pg/ml after 3 h from O2 removal; NS). On the contrary, in patients affected by COPD, plasma DLS levels increased during O2 administration (from basal values of 138.98 +/- 8.31 to 202.14 +/- 8.21 pg/ml at 180 min; p < 0.05), and returned to baseline levels (142.59 +/- 8.28 pg/ml) 3 h after O2 removal. In the same patients, DLS increase was accompanied by a rise in Na+ excretion (from 0.08 +/- 0.01 at time 0 to 0.16 +/- 0.02 mEq/min after 3 h of O2 administration; p < 0.05). In conclusion, our findings showed an oxygen-related increase in plasma DLS levels and in urinary Na+ excretion in patients affected by COPD. This phenomenon could promote Na+ urinary loss during prolonged O2 therapy in these patients and should be taken into account in their management.     

Comparison of 0.25% ropivacaine and bupivacaine for epidural analgesia for labor and vaginal delivery

STUDY OBJECTIVE: Part 1: To measure ropivacaine levels in the mother and infant at delivery after continuous lumbar epidural infusion. Part 2: To compare epidural ropivacaine to epidural bupivacaine for labor analgesia in regard to effectiveness, motor blockade, and maternal and neonatal effects. DESIGN: Part 1: Open-labelled, non-blind study. Part 2: Randomized, double-blind study. SETTING: Labor and delivery units of two academic hospitals. PATIENTS: Part 1: 20 ASA physical status I and II parturients in active labor. Part 2: 81 ASA physical status I and II parturients in active labor. INTERVENTIONS: For Part 1, 8 to 12 ml of 0.25% ropivacaine was administered through a lumbar epidural catheter to achieve a T10 dermatomal sensory level. An infusion of 0.25% ropivacaine, 8 to 10 ml/hr, maintained this sensory level. Maternal and umbilical cord blood samples obtained at delivery were analyzed for ropivacaine concentration. For Part 2, anesthetic management was similar to that previously described except patients were randomized to receive either 0.25% ropivacaine or 0.25% bupivacaine. Onset, regression, maximal spread of sensory block, and onset and degree of motor blockade were measured. Contraction pain as assessed using a visual analog scale (VAS), maternal blood pressure, and heart rate were determined every 5 minutes until a stable VAS-contraction score was achieved, and every 30 minutes thereafter. Neonatal assessment included Apgar scores and neurologic and adaptive capacity scores (NACS) at 15 minutes, 2 hours, and 24 hours. MEASUREMENTS AND MAIN RESULTS: For Part 1, the total and free maternal arterial concentrations of ropivacaine at delivery were 0.64 +/- 0.14 microgram/ml and 0.10 +/- .02 microgram/ml, respectively; the umbilical venous total and free concentrations were 0.19 +/- 0.03 microgram/ml and 0.12 +/- 0.07 microgram/ml, respectively (n = 12). The umbilical arterial and venous concentrations did not differ for both the free and total concentrations. For Part 2, there was no difference between ropivacaine and bupivacaine in the variables measured. Umbilical cord gases and Apgar scores were not different between the two groups; NACS were higher at 15 minutes and 2 hours in the ropivacaine group (p < 0.05) than the bupivacaine group. CONCLUSION: Both ropivacaine and bupivacaine produced excellent analgesia for labor with no major adverse effect on the mother or neonate.