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K Sombolos

Publications and source records attributed to K Sombolos.

At least 19 recordsLinked to original sources
PubMed2006

Hemoglobin changes at the initiation of high-flux hemodialysis.

BACKGROUND: The aim of the present study was to assess hemoglobin changes occurring at the beginning of high-flux hemodialysis (HD). METHODS: In a group of 20 chronic HD patients (group A), total hemoglobin (tHb), hematocrit (Hct) and total serum proteins (TP) were measured in blood samples drawn from an arterial fistula needle before the initiation of high-flux HD, and from an arterial line 5 min after HD with the dialysate in the bypass mode. 31 chronic stable HD patients (group B) served as controls. In group B patients, tHb was measured in blood samples drawn from an arterial fistula needle before the initiation of high-flux HD, and from arterial and venous lines simultaneously 5 min later. Blood flow rates in groups A and B were set from the beginning of the study to 300 ml/min, while the bicarbonate dialysate flow rate and ultrafiltration rate in group B patients was set to 700 ml/min and zero, respectively. The same high-flux dialyzer was used for all patients (FLX-18, membrane PEPA 1.8 m(2)). RESULTS: A comparison of baseline (pre-dialysis) values with those derived from an analysis of the arterial line in groups A and B at 5 min revealed that tHb decreased by 0.6 +/- 0.2 g/dl (5.2 +/- 1.7%, p < 0.001) and 0.7 +/- 0.7 g/dl (5.4 +/- 6.2%, p < 0.001), respectively. At the same time, Hct and TP in group A decreased by 1.32 +/- 0.7% (3.8 +/- 2.0%, p <0.001) and 0.3 +/- 0.1 g/dl (4.8 +/- 1.4%, p < 0.001), respectively. Blood volume (BV) and plasma volume (PV) in group A patients at 5 min as calculated from tHb and TP values increased by 5.6 +/- 1.9 and 5.2 +/- 1.7%, respectively, while BV in group B patients increased by 6.1 +/- 7.0% (not significant when compared to group A). tHb did not change significantly in 14 patients (group C) studied immediately after adopting the supine position and 5 min later in the absence of HD. CONCLUSION: A 5% decrease in tHb was observed 5 min after the initiation of high-flux HD with a zero ultrafiltration rate, and was due to an increase in BV.

Acid-Base Equilibrium↗
PubMed2000

Prosthetic graft placement using the deep forearm veins in hemodialysis patients: a preliminary report.

When the superficial arm veins are not suitable for the creation of a conventional endogenous arteriovenous (A-V) fistula or the placement of a prosthetic graft in the forearm, the use of the deep forearm veins as an outflow system to construct an A-V graft access seems to be a reasonable alternative. Using this approach, we placed 6 prosthetic grafts in 6 hemodialysis patients in whom conventional methods had failed. Adequate functioning of this 'deep vein'-type vascular access in these 6 patients has been maintained for 3, 6, 11, 15, 19 and 24 months, respectively, without complications or any need for further interventions. Only one graft failed after 6 months. Our preliminary results indicate that this technique can be used successfully when the superficial forearm veins have been exhausted, thus avoiding the use of upper-arm or axillary veins.

Adult↗
PubMed1998

Serum ferritin levels are increased in patients with acute renal failure.

After having observed high serum ferritin concentrations in some patients with acute renal failure (ARF) we decided to evaluate serum ferritin and iron levels in patients with acute and chronic renal failure (CRF). The concentrations of BUN, serum creatinine, Hct, Hb, serum iron and serum ferritin were measured in 47 patients with renal failure who were divided into two groups (A and B). Group A included 24 patients with ARF (19 M, 5 F) and group B 23 patients with CRF (12 M, 11 F). The diagnosis of ARF or CRF was based on patients' history and clinical examination and confirmed by the standard laboratory findings and the subsequent clinical outcome. None of the patients had received iron, blood transfusions or erythropoietin during the last six months and none had malignancy or primary liver diseases. As controls were used 20 normal volunteers (group C) and 10 patients with acute infections (group D). Comparing groups A and B we did not found any difference in BUN, creatinine and serum iron levels. However patients in group A had significantly higher serum ferritin levels (1000 +/- 752 vs 90 +/- 56 ng/dl, p = 0.0001), higher Hct (31.8 +/- 4.4 vs 25.3 +/- 4.1%, p = 0.0001) and higher Hb concentrations (10.5 +/- 1.7 vs 8.1 +/- 1.4 g/dl, p = 0.0001). Ferritin levels in patients with ARF were also higher than the corresponding levels of normal controls (group C) (p = 0.0001), but did not differ significantly from those measured in patients with acute infection (group D). We conclude that in patients with acute renal failure serum ferritin levels are increased and do not reflect serum iron levels.

Acute Kidney Injury↗
PubMed1997

Plasmapheresis in toxic epidermal necrolysis.

BACKGROUND: The treatment of toxic epidermal necrolysis (TEN) is usually based on the removal of the offending drug(s), fluid replacement, nutritional support, and local management. The mortality and morbidity, however, remain high and the death rate may be reduced to 10% only in special centers that use biologic dressings. Plasma exchange (PE) was proven efficacious in small series of patients and of no particular value in others. METHODS: Seven patients suffering from severe TEN covering 30%-80% of body surface area and having two or four mucous membranes involved, were included in this open study. Malignancy (Hodgkin's disease, brain tumor) and a variety of medicaments (carbamazepine, allopurinol, diphenylhydantoin, cefaclor, amoxicyllin with clavullanic acid) were considered as causally implicated. One to four PEs of 2.5 L were given on alternate days in six patients and on a daily basis in the seventh. RESULTS: All patients recovered successfully from their disease. No new lesions appeared after the first PE in four patients. Neither adverse reactions from this therapy nor sequelae from TEN were observed after a long follow-up lasting up to 8 years. CONCLUSIONS: Although PE is expensive and requires easy venous access to be performed, it could be listed in the first line of TEN therapy. The method is safe and efficacious, providing prompt relief from pain and rapid cessation of necrolysis. The alternate day PEs are considered preferable to the everyday regimen.

Adolescent↗
PubMed1997

Clinical evaluation of four different high-flux hemodialyzers under conventional conditions in vivo.

Four types of high-flux hemodialyzers, Primus 2000 (high-flux polysulfone 2.0 m2), Altra-Flux 170 G (cellulose diacetate 1.7 m2), FLX-15 GW (polyester-polymer alloy 1.5 m2) and PAN-85 DX (polyacrylonitrile 1.7 m2) were evaluated in vivo. A total of 12 stable chronic hemodialysis patients participated in the study and each type of dialyzer was tested once in 9 of them. Blood samples for the measurement of BUN, creatinine, phosphate, uric acid, albumin and beta2-microglobulin (beta2M) were drawn before and 5 min after the end of the study dialysis. During dialysis, which was performed in all patients with a blood flow rate of 250 ml/min for 240 min, the dialysate (550-600 ml/min) was collected every hour and samples were drawn for the measurements of all the above substances. The mean total amount of low-molecular substances removed per session by each dialyzer was very close to 19.5 g for urea, 2.0 g for creatinine, 0.9 g for phosphate and 1 g for uric acid. The one-third (30-33%) of the above amounts were removed during the first hour of dialysis. Dialyzers' clearances for creatinine and uric acid were significantly higher in Primus dialyzer comparing to FLX-15 GW (p < 0.05) while the clearance for urea showed a borderline significance (p = 0.055). No difference was found either among Altra-Flux 170 G, FLX-15 GW and PAN-85 DX or between Primus and PAN-85 DX dialyzers. Phosphate clearance did not show any difference among the four dialyzers. The lowest amount of albumin removed per session was 0.75 g by PAN-85 DX and the highest 1.8 g by FLX-15 GW, while the equivalents for beta2M were 80 mg by Altra-Flux 170 G and 142 mg by PAN-85 DX. A significant adsorption of beta2M on these dialysis membranes was indicated by the combination of a satisfactory serum beta2M reduction ratio (post-/predialysis values = 0.52, 0.77, 0.60, 0.55) with a reduced beta2M clearance (23.9, 13.6, 20.2, 25.1 ml/min). During the first hour of dialysis, in comparison to the following time, the highest amounts of albumin and beta2M (expressed as percentage of total) were removed by the Primus 2000 dialyzer. Our results indicate that under conventional conditions small differences in the surface area of the high-flux dialyzers are unimportant regarding the removal of low molecules. However, the composition of the membrane seems to play an important role in the removal of high-molecular substances.

Acrylic Resins↗
PubMed1996

Urea concentration gradients during conventional hemodialysis.

To elucidate the intradialytic urea concentration gradients, we examined 26 hemodialysis patients wearing a double-lumen central venous catheter during their first or second fistula-punctured dialysis session. In 17 patients (group A), after 60 and 240 minutes of treatment with a mean blood flow of 196.4 +/- 9.9 mL/min, blood urea nitrogen (BUN) was measured in blood samples taken simultaneously from the central venous catheter, a vein in the arm opposite the access site, and the arterial and venous lines of the dialyzer. In 16 patients (group B), after 60 minutes of treatment with a mean blood flow rate of 197.5 +/- 12.3 mL/min, BUN was measured in blood samples taken from the dialyzer arterial line and then, after decreasing the blood flow to 50 to 60 mL/min for 1 minute, in samples taken from a vein in the arm opposite the access site, the central venous catheter, and the dialyzer arterial line. In group A, the mean BUN values in the dialyzer arterial line at 60 and 240 minutes were found to be 3.7% +/- 3.7% and 3.5% +/- 3.4% higher than the corresponding values in the central veins, respectively (P = NS between 60 and 240 minutes). In group B, after 1 minute of low blood flow, this difference was 1.5% +/- 2.4% (P = 0.06 compared with group A). The peripheral veins in group A patients at 60 and 240 minutes had 9.7% +/- 5.2% and 10.9% +/- 5.3% higher BUN values, respectively, compared with the central veins. This difference in group B patients after 1 minute of low blood flow was 6.8% +/- 4.2%. Urea access recirculation rate in group A, calculated by the classical three-samples method, was found to be 7.6% +/- 5.0% at 60 minutes and 9.9% +/- 5.8% at 240 minutes (P = NS). In group B, BUN values in the dialyzer arterial line after 1 minute of low blood flow increased significantly by 3.4% +/- 4.5% (P < 0.01). Our study shows that during conventional hemodialysis with a blood flow rate of 200 mL/min, urea concentration in the central veins is lower than in the dialyzer arterial line. This gradient after 1 minute of low-flow dialysis had a tendency to decrease. At the same time, however, the urea concentration gradient between the peripheral and central veins remained high, indicating that during conventional hemodialysis, intercompartmental disequilibrium plays a significant role in the arteriovenous gradient.

Arm↗
PubMed1994

Influence of continuous haemofiltration-related hypothermia on haemodynamic variables and gas exchange in septic patients.

OBJECTIVE: To investigate the influence of continuous haemofiltration (CHF) on haemodynamics, gas exchange and core temperature in critically ill septic patients with acute renal failure. PATIENTS AND METHODS: In 20 patients (17 male, 3 female) ultrafiltration rate, core temperature, gas exchange and haemodynamic variables were measured at regular intervals during the first 48 h of haemofiltration. Baseline data were compared to those obtained 30 min after initiating CHF and also to those during hypothermia (if observed). MAIN RESULTS: Haemodynamic variables remained remarkably constant throughout the study period. In patients with a relatively low ultrafiltration rate (855 +/- 278 ml/h) temperature did not change, while in patients with a high ultrafiltration rate (1468 +/- 293 ml/h) core temperature significantly decreased from 37.6 +/- 0.9 degrees C to 34.8 +/- 0.8 degrees C (p < 0.001). There was a statistically significant correlation between temperature decrease and ultrafiltration rate (r = -0.68, Y = 1.8-0.003 X, p < 0.01). Hypothermic patients also showed a mean decrease in VO2 from 141 +/- 22 ml/min/m2 to 112 +/- 22 ml/min/m2 (p < 0.01) with a concomitant increase in PaO2 from 103 +/- 37 mmHg to 140 +/- 42 mmHg (p < 0.001) and in PvO2 from 35 +/- 4 mmHg to 41 +/- 5 mmHg (p < 0.001). CONCLUSIONS: 1) Continuous haemofiltration does not cause significant alternations in haemodynamic variables. 2) Hypothermia frequently occurs in patients undergoing continuous haemofiltration with high ultrafiltration rates. These hypothermic patients show a reduction in VO2 leading to an increase in PvO2 and PaO2. This mild hypothermia in these circumstances has no evident deleterious effects.

Acute Kidney Injury↗
PubMed1993

Supraglottic laryngectomy: experience with 66 patients over 20 years.

We reviewed the records of 66 consecutive patients with previously untreated supraglottic laryngeal carcinoma who underwent a supraglottic laryngectomy in our department between 1970 and 1989. There were 23 T1, 30 T2 and 13 T3 cases. Eight patients had neck metastases and underwent neck dissection also. Twenty-four (36 per cent) patients received post-operative radiotherapy. Two-year and five-year survival rates were 88.9 per cent and 82.2 per cent respectively. When the survival rates of the patients with T1, T2 and T3 lesions were calculated separately and compared with each other the differences were not statistically significant. Recurrences, post-operative complications, time to progression and indications for supraglottic laryngectomy are discussed.

Adult↗
PubMed1993

Efficacy of dual lumen jugular venous catheter hemodialysis when venous lumen is used as arterial lumen.

In 12 patients who underwent hemodialysis by a dual lumen jugular venous catheter, urea recirculation rate was measured during conventional treatment under normal conditions (R1), as well as when the venous lumen of the catheter was used as arterial lumen and the arterial as venous lumen (R2). Although the mean value of R2 was, as expected, higher than R1 (8.25 +/- 2.7 versus 4.25 +/- 1.00; p = 0.0004), it was still within the acceptable rate. We conclude that during hemodialysis by a dual lumen jugular venous catheter, efficient treatment can be provided when the venous is used as arterial lumen.

Adult↗
PubMed1993

Long-term continuous ambulatory peritoneal dialysis.

Of 174 patients who entered our CAPD program, 58 received transplants, 7 were transferred to another center, one recovered satisfactory kidney function, 22 were transferred to hemodialysis, 24 to IPD, 52 died and 10 remained on CAPD for at least seven years, when this study was completed. These 10 patients (8 women and 2 men) who are described here in detail had a median age of 46 (range of 24 to 63) years at entry. Their primary renal disease was glomerulonephritis (6), polycystic kidney disease (2), nephrosclerosis (1) and Alport's disease (1). They spent 91 to 134 (average 113) months on CAPD. They had a significant (p = 0.025) increase in body weight from 54.5 +/- 2.8 kg to 59.6 +/- 3.0 kg during the first 3 years, and a decrease in ultrafiltration capacity; BUN and serum creatinine remained relatively stable. Mean total protein and serum albumin remained unchanged at 65 and 35 g/l respectively, throughout the study. There were no significant changes in the hemoglobin and lipid values. Renal osteodystrophy progressed slowly. Peritonitis rate in this group was one episode every 18.9 patient months. These 10 patients had a total of 25 catheters implanted during the study period. The average hospitalization rate was 8.76 days per patient year, 5.34 of which were for peritonitis. Of these 10 patients, one was transferred to hemodialysis, 5 died (4 of or during peritonitis, one of myocardial infarction) and 4 remained on CAPD. Our experience with these 10 patients indicates that CAPD can be carried out over long periods.(ABSTRACT TRUNCATED AT 250 WORDS)

Body Weight↗
PubMed1992

Vertical partial laryngectomy: our results after treating 81 cases of T2 and T3 laryngeal carcinomas.

From 1976 to 1989, 81 patients with T2 and T3 laryngeal carcinomas were treated with vertical patrial laryngectomy at the University ENT Department of Thessaloniki, Greece. All patients were male with a median age of 56 years (33-71 years). Four patients had N1 lymph nodes. Ten patients received post-operative radiotherapy. Seventeen patients developed local recurrences or distant metastases. Mean follow-up was more than seven years. Absolute three-year survival was 94.6 per cent for 74 patients and absolute five-year survival was 89.6 per cent for 58 patients. Actuarial five-year survival of the whole group of 81 patients was 91 per cent calculated with the Kaplan-Meier method. Recurrence rate and survival of stage II and III patients are also discussed and compared using the log-rank test. We conclude that vertical partial laryngectomy is a very successful treatment selection for T2 glottic and false vocal cord carcinomas and for some selected T3 glottic lesions.

Adult↗
PubMed1991

Carboplatin, continuous infusion fluorouracil and mid-cycle high-dose methotrexate as initial treatment in patients with locally advanced head and neck cancer. Hellenic Co-operative Oncology Group Study.

Forty-nine patients with locally advanced squamous cell carcinoma of the head and neck (SCCHN) were treated with 3 cycles of induction chemotherapy prior to definitive local treatment (surgery and/or radiation therapy). Chemotherapy consisted of carboplatin 300 mg/m2 on day 1, fluorouracil 1000 mg/m2 daily as a continuous infusion on days 1 to 5 and high-dose methotrexate 1.2 g/m2 with leucovorin rescue on day 14. After completing the induction chemotherapy, 9 patients (18%) achieved a complete remission (CR), 26 (54%) a partial remission (PR), 7 had stable disease and 7 a progression. The response rates increased to 53% CR and 18% PR following locoregional treatment. Survival at 12 months was 61% and its actuarial probability at 24 months 31%. Median time to progression was 14 months. Toxicity from chemotherapy was generally mild. Nausea was observed in 35%, vomiting in 26%, stomatitis in 57%, anemia in 22%, leukopenia in 36%, thrombocytopenia in 26% and diarrhea in 6% of the patients. In conclusion, the combination of carboplatin, 5-day continuous-infusion fluorouracil and mid-cycle high-dose methotrexate is a moderately effective, well tolerated regimen in patients with SCCHN but does not seem superior to the combination of carboplatin and fluorouracil only.

Aged↗
PubMed1991

Lack of correlation between urea kinetic indices and clinical outcomes in CAPD patients.

We examined the predictive value of urea kinetics for patient outcomes in CAPD by measuring dialysis index (DI; a means of quantifying CAPD dose using urea kinetics), KT/V and normalized protein catabolic rate (PCRN) on 222 occasions in 76 new patients at the time of starting CAPD and at subsequent six month intervals. We investigated how these indices altered with time and in relation to each other, and how they correlated with a wide range of subsequent patient outcomes. DI, KT/V and PCRN all tended to decrease with time on CAPD (P less than 0.0004, less than 0.0001 and 0.0005, respectively). DI and KT/V were highly correlated with each other (r = 0.89, P less than 0.0001) and both correlated with PCRN (r = 0.57, P less than 0.0001 and r = 0.60, P less than 0.0001, respectively). DI and KT/V both correlated inversely with subsequent values for serum creatinine (P less than 0.0001), urea (P less than 0.0002), potassium (P less than 0.02) and phosphate (P less than 0.002), and directly with bicarbonate (P less than 0.0001). PCRN correlated inversely with serum creatinine (P less than 0.0002) and directly with urea (P less than 0.0001) and with the number of blood transfusions received (P less than 0.03). None of these indices correlated with levels of hemoglobin, PTH, alkaline phosphatase or albumin, or with nerve conduction velocity or any other subsequent clinical outcomes including death, technique failure, hospital days, peritonitis rate and subjective indices of fatigue, pruritus and insomnia. We conclude that the urea kinetic model is predictive of some biochemical outcomes but not of clinical outcomes in CAPD patients.

Adolescent↗