Titanium dioxide nanoparticles require K+ and hydrogen sulfide to regulate nitrogen and carbohydrate metabolism during adaptive response to drought and nickel stress in cucumber.

Crop plants face severe yield losses worldwide owing to their exposure to multiple abiotic stresses. The study described here, was conducted to comprehend the response of cucumber seedlings to drought (induced by 15% w/v polyethylene glycol 8000; PEG) and nickel (Ni) stress in presence or absence of titanium dioxide nanoparticle (nTiO2). In addition, it was also investigated how nitrogen (N) and carbohydrate metabolism, as well as the defense system, are affected by endogenous potassium (K+) and hydrogen sulfide (H2S). Cucumber seedlings were subjected to Ni stress and drought, which led to oxidative stress and triggered the defense system. Under the stress, N and carbohydrate metabolism were differentially affected. Supplementation of the stressed seedlings with nTiO2 (15 mg L-1) enhanced the activity of antioxidant enzymes, ascorbate-glutathione (AsA-GSH) system and elevated N and carbohydrates metabolism. Application of nTiO2 also enhanced the accumulation of phytochelatins and activity of the enzymes of glyoxalase system that provided additional protection against the metal and toxic methylglyoxal. Osmotic stress brought on by PEG and Ni, was countered by the increase of proline and carbohydrates levels, which helped the seedlings keep their optimal level of hydration. Application nTiO2 improved the biosynthesis of H2S and K+ retention through regulating Cys biosynthesis and H+-ATPase activity, respectively. Observed outcomes lead to the conclusion that nTiO2 maintains redox homeostasis, and normal functioning of N and carbohydrates metabolism that resulted in the protection of cucumber seedlings against drought and Ni stress. Use of 20 mM tetraethylammonium chloride (K+- channel blocker), 500 µM sodium orthovanadate (PM H+-ATPase inhibitor), and 1 mM hypotaurine (H2S scavenger) demonstrate that endogenous K+ and H2S were crucial for the nTiO2-induced modulation of plants' adaptive responses to the imposed stress.

Radiopharmaceutical Encapsulated Liposomes as a Novel Radiotracer Im - aging and Drug Delivery Protocol.

Nuclear medicine specialty involves the administration of unsealed radioactive substances to patients to allow specific diagnostics and treatments using radiopharmaceuticals, radiotracers, and materials. Developing a radiopharmaceutical must involve considering and addressing some limitations such as its retention by unintended organs, which can influence patient and worker safety, imaging findings, and diagnostic and therapeutic accuracy. This paper presents data on the changing biodistribution, localization, stability, and accuracy patterns of radiopharmaceuticals by liposome encapsulation. METHODS: Data are presented for 5 male New Zealand white rabbits. They were injected intravenously with the 99mTc-liposomes encapsulated MIBI through a marginal ear vein, and whole-body images were acquired using a dual-head gamma camera. Cationic PEGylated liposomes were prepared using the conventional thin-film-hydration method. The liposomes were tested for particle size, zeta potential, high-performance-liquid-chromatography (HPLC), and toxicity. RESULTS: The liver activity was slightly greater than or equivalent to heart uptake, using 99mTcsestamibi, MIBI, without liposome as a reference. The absorbed doses in myocardium cells after injecting rabbits with 99mTc-MIBI labeled with free positive lower pH liposomes was greater than in the liver, whereas 99mTc labeled with encapsulated MIBI within positive liposomes showed a significantly higher heart-to-liver ratio. The heart-to-spleen activity uptake ratio in 99mTc-MIBI was higher than or equal to one but increased in 99mTc labeled with MIBI and free positive liposomes. Injecting rabbits with 99mTc labeled with encapsulated MIBI raised myocardium uptake to 2-4 times more than the spleen. Heart-to-bowel activity began to rise with 99m Tc-labeld-MIBI and liposomes. CONCLUSION: This study provides findings in radiopharmaceutical biodistribution using liposomal agents. Adding free liposomes using a pH gradient technique enhanced the uptake and localization of the radiotracer. However, tracer encapsulation during the formation of the liposomes showed even better specificity.

Enhanced Efficacy of Radiopharmaceuticals When Using Technetium-99m-Labeled Liposomal Agents: Synthesis and Pharmacokinetic Properties.

Challenges posed by the retention of radiopharmaceuticals in unintended organs affect the quality of patient procedures when undergoing diagnostics and therapeutics. The aim of this study was to formulate a suitable tracer encapsulated in liposomes using different techniques and compounds to enhance the stability, uptake, clearance, and cytotoxic effect of the radiopharmaceutical. Cationic liposomes were prepared by a thin-film method using dipalmitoyl phosphatidylcholine (DPPC) and cholesterol. Whole-body gamma camera images were acquired of intravenously injected New Zealand rabbits. Additionally, liposomes were assessed using stability, toxicity, zeta potential, and particle size tests. In the control cases, Technetium-99m (99mTc)-sestamibi exhibited the lowest heart uptake the blood pool and delayed images compared to both 99mTc-liposomal agents. Liver and spleen uptake in the control samples with 99mTc-sestamibi increased in 1-h-delayed images, unlike with 99mTc-liposomal agents, which were decreased in delayed images. The mean maximum count in the bladder for 99mTc-sestamibi loaded liposomes 1 h post-injection was 2354.6 (±2.6%) compared to 178.4 (±0.54%) for 99mTc-sestamibi without liposomes. Liposomal encapsulation reduced the cytotoxic effect of the sestamibi. 99mTc-MIBI-cationic liposomes exhibited excellent early uptake and clearance compared to 99mTc-MIBI without liposomes. Adding cholesterol during liposome formation enhanced the stability and specificity of the targeted organs.

Long-term outcome after endoscopic ligation of acute esophageal variceal bleeding in patients with liver cirrhosis.

Endoscopic variceal ligation (EVL) has been the standard treatment for acute variceal bleeding (AVB). However, reports of long-term prognosis after EVL are scarce. Therefore, the current work aimed to investigate the long-term outcome and prognostic modifiers of cirrhotic cases presented with acute esophageal variceal bleeding and managed with EVL. The current prospective work comprised primarily 276 consecutive grown-up cirrhotic cases presenting with AVB and managed with EVL. Two-hundred patients who completed the study till death or 3-year follow-up were enrolled in final analysis. The primary outcome measure was occurrence of rebleeding and all-cause mortality. By the end of follow up 56 patients (28%) developed rebleeding and 78 (39%) died. The independent factors associated with rebleeding were lacking follow up EVL (OR: 4.8, 95%CI: 1.9-12.2), BMI > 30 kg/m2 (OR: 0.-, 95%CI: 0.2-0.9), Child class C (OR: 3.8, 95%CI: 1.8-7.8), and grade IV varices (OR: 2.6, 95%CI: 1.3-5.3). The independent factors associated with mortality were: Age > 65 years (OR: 32.4, 95%CI: 8.7-120.3), rebleeding (OR: 98.4, 95%CI: 27.9-347.0), coexistence of HCC (OR: 7.4, 95%CI: 2.0-27.4), and lacking follow up EVL (OR: 6.1, 95%CI: 1.2-31.1). Recurrent bleeding after emergency endoscopic ligation of acute esophageal variceal bleeding in cirrhotic cases is a rather common complication that significantly increases the mortality rate. The liver condition, lack of follow up endoscopy, old age, and severity of esophageal varices are independent prognostic indicator of rebleeding and morality.

Imatinib for highly chemoresistant Kaposi sarcoma in a patient with long-term HIV control: a case report and literature review.

Kaposi sarcoma (ks) is a vascular tumour caused by oncogenic human herpesvirus type 8; it often occurs with hiv-associated immunosuppression. Numerous cellular signalling pathways are involved in the pathogenesis of ks, among which receptor tyrosine kinases such as the c-Kit and platelet-derived growth factor receptors play an important role. Imatinib mesylate, a tyrosine kinase inhibitor, has resulted in partial regression of ks lesions in one third of treated patients, but its mechanism of action remains unclear. Here, we report the case of a white man with recurrent ks despite well-suppressed hiv infection and multiple chemotherapies who received imatinib and showed a complete and sustained tumour response. To our knowledge, this report is the first showing the value of imatinib in the management of ks in the context of long-lasting hiv control with adequate quantitative CD4 recovery. Our case indicates that imatinib can be a treatment option for highly chemoresistant recurrent ks in patients on long-term antiretroviral therapy.

'Danger' effect of low-density lipoprotein (LDL) and oxidized LDL on human immature dendritic cells.

Dendritic cell (DC) maturation may accelerate autoimmune diseases such as systemic lupus erythematosus and rheumatoid arthritis, and may contribute to accelerated atherosclerosis seen in these patients. The immune system responds to both exogenous and endogenous 'dangerous' signals that can induce dendritic cell maturation. We have found that autologous plasma contains danger signals that induce up-regulation of major histocompatibility complex (MHC) class II and co-stimulatory molecules in immature DCs (iDCs). The objective of this study was to determine whether low-density lipoprotein (LDL) and/or oxidized LDL (oxLDL) constitute danger signals, and to assess the effect of exposure to LDL and oxLDL following monocyte differentiation into iDCs in lipoprotein-deficient serum (LPDS). IDCs were generated in the presence of autologous plasma or LPDS. Expression of maturation and migration molecules was evaluated using flow cytometry, and morphology was assessed by light microscopy. Pro- or anti-apoptotic effect was determined using annexin V and propidium iodide binding. Phagocytosis of apoptotic cells was evaluated using autologous plasma or LPDS. LDL and oxLDL were clearly able to slightly up-regulate levels of HLA-DR and co-stimulatory molecule CD86. High oxLDL concentrations (50-100 microg/ml) were associated with expression of additional maturation molecules. Moreover, iDCs that were prepared in LPDS showed partial maturation following exposure to LDL and oxLDL, and improved tolerogenic apoptotic cell uptake. This study suggests that oxLDL, and to some extent LDL, are at least partly responsible for the iDC 'danger' response induced by autologous plasma.

Low-dose bupivacaine spinal anaesthesia for percutaneous nephrolithotomy: the suitability and impact of adding intrathecal fentanyl.

BACKGROUND: Unilateral spinal anaesthesia has been used for lower limb surgery with a stable cardiovascular state and a short recovery unit stay. We sought to test the suitability of low-dose bupivacaine spinal anaesthesia for percutaneous nephrolithotomy, a procedure hitherto performed under general anaesthesia. Furthermore, we hypothesized that adding intrathecal fentanyl to bupivacaine may improve the quality of anaesthesia. METHODS: We randomly allocated, through computer-generated randomization, 108 patients subjected to percutaneous nephrolithotomy to receive either 7.5 mg of hyperbaric bupivacaine 5 mg/ml alone or with the addition of 10 microg of fentanyl. Drugs were given at the L(2)-L(3) interspace with the patient in the lateral decubitus position. The patients remained in this position for 10 min, after which the sensory and motor blocks were assessed. Intra-operative analgesic supplementation, when deemed necessary, was achieved with intravenous fentanyl boluses (25 microg). RESULTS: The sensory and motor blocks after intrathecal bupivacaine and bupivacaine-fentanyl were similar. Sensory block, in both groups, reached the fifth and eighth thoracic dermatomes on the operative and non-operative sides, respectively. Deep motor block occurred on the operative side in all patients and in nearly 50% of patients on the non-operative side. The patients in the bupivacaine-fentanyl group required less intra-operative and post-operative analgesics, and both patients and endoscopists were better satisfied. CONCLUSION: This study demonstrated, for the first time, that intrathecal low-dose bupivacaine and fentanyl offers a reliable neuraxial block for patients subjected to percutaneous nephrolithotomy, with stable haemodynamics, good post-operative analgesia and acceptable patient and endoscopist satisfaction.

Development of a difficulty score for spinal anaesthesia.

BACKGROUND: Multiple attempts at spinal puncture may be hazardous. Accurate preoperative prediction of difficulty adds to the delivery of high quality care. This clinical trial was designed to: (i). determine the predictive performance of difficulty variables; (ii). compare senior and junior anaesthetists; (iii). develop a score to predict difficulty during the performance of spinal anaesthesia. METHODS: A total of 300 patients subjected to urological procedures and scheduled for spinal anaesthesia were independently assessed and stratified according to the categories of the difficulty predictors of spinal anaesthesia into one of nine grades (0-8) and randomized according to the experience of the anaesthetist into two groups (group A, staff with more than 15 yrs' experience; group B, resident with more than 6 months but less than 1 yr in training). The number of attempts and levels, and success rate of the technique were the outcome variables. Data were analysed by multivariate analysis and receiver operating characteristic (ROC) curves. RESULTS: The bony landmarks of the back and the radiological characteristics of the lumbar vertebrae were two independent predictors of difficulty. Multivariate analysis indicated differences between junior and senior staff but ROC curves indicated no difference. Grade 4 was the difficulty score at or above which difficulty was expected whether or not radiological characteristics of the vertebrae were included. CONCLUSIONS: Spinal bony landmarks and radiological characteristics of the lumbar vertebrae are independent predictors of difficulty during spinal anaesthesia. There is no difference between senior and junior anaesthetists. Grade 4 is the difficulty score at or above which difficulty is expected.

Total intravenous anaesthesia with ketamine-midazolam versus halothane-nitrous oxide-oxygen anaesthesia for prolonged abdominal surgery.

BACKGROUND AND OBJECTIVE: Total intravenous anaesthesia (TIVA) with ketamine-midazolam (KM) can be used for prolonged abdominal surgery. We compared this technique with halothane-nitrous oxide-oxygen anaesthesia using haemodynamic and endocrine stress responses as primary outcomes and adequacy of operating conditions and recovery profile as secondary outcomes. METHODS: Fifty adult patients undergoing radical cystectomy and bladder substitution were randomly assigned to receive either TIVA with KM (n = 25) or halothane, nitrous oxide and oxygen anaesthesia (n = 25). Invasive haemodynamic and oxygenation variables were monitored along with plasma cortisol and growth hormone concentrations. Operative conditions and recovery profiles were registered. RESULTS: Cardiac index and vascular resistance remained stable during and after surgery. Cortisol concentrations doubled during surgery and remained elevated in the recovery period. Growth hormone increased after induction, peaked during surgery and decreased during recovery. Neither the haemodynamic variables nor the plasma hormone concentrations differed significantly between the two groups. Intestinal loops were collapsed in the KM groups providing better operative conditions and a reduced need for postoperative analgesics. CONCLUSIONS: The stress responses during KM anaesthesia for prolonged abdominal surgery were comparable to those during halothane-nitrous oxide-oxygen anaesthesia. However, KM anaesthesia provided better surgical conditions and better recovery.

Ketamine-midazolam total intravenous anaesthesia for prolonged abdominal surgery.

BACKGROUND AND AIM: Infusion of ketamine and midazolam can maintain prolonged anaesthesia, but delayed recovery is a limitation. We aimed to develop an approximation regimen for the infusion of ketamine and midazolam to obtain steady-state anaesthesia with acceptable recovery. METHODS: Thirty-one patients undergoing radical cystectomy were studied. The initial regimen was calculated from drug pharmacokinetic variables and tailored in a pilot study (15 patients) to develop the approximation regimen dosage. Anaesthesia was induced with midazolam (150 micrograms kg-1) and ketamine (2 mg kg-1). Tracheal intubation and ventilation with oxygen enriched air (FiO2 = 0.35) were facilitated by muscle relaxants. Anaesthesia was maintained by the approximation regimen doses. Routine monitoring was used for all patients, but pulmonary artery catheters were inserted in 11 patients, to obtain haemodynamic and oxygenation variables. RESULTS: Steady-state anaesthesia was obtained with minimal deviations in the regimen in some patients followed by reasonable recovery. CONCLUSION: It is concluded that infusion of ketamine and midazolam in the approximation regimen doses can be used to maintain anaesthesia for prolonged abdominal surgery.

Faster image template matching in the sum of the absolute value of differences measure.

Given an m x m image I and a smaller n x n image P, the computation of an (m-n+1) x (m-n+1) matrix C where C(i, j) is of the form C(i,j)=Sigma(k=0)(n-1)Sigma(k'=0)(n-1)f(I(i+k,j+k'), P(k,k')), 0= or

Can we increase hepatic oxygen availability? The role of intentional hypercarbia.

Our hypothesis is that hypercarbia produces sympathetic stimulant effect and local vasodilatation. We studied the effect of intentional hypercarbia (IHC) on hepatic venous oxygen saturation. The hepatic vein (HV) was cannulated in 15 patients through either the right internal jugular vein or the femoral vein to measure HV oxygen saturation and calculate oxygen content. The inferior vena cava (IVC) was cannulated in 6 patients above and below drainage of the hepatic veins for oxygen saturation and content difference along the IVC. IHC was achieved in awake patients by breathing oxygen enriched air at a flow rate of 2L/min for 10 min, and during anesthesia by increasing anesthetic dead space and reducing tidal volume. IHC increased HV blood oxygen saturation, decreased the arterio-hepatic vein oxygen content difference and decreased oxygen saturation difference and oxygen content difference along IVC.

A novel plant glutathione S-transferase/peroxidase suppresses Bax lethality in yeast.

The mammalian inducer of apoptosis Bax is lethal when expressed in yeast and plant cells. To identify potential inhibitors of Bax in plants we transformed yeast cells expressing Bax with a tomato cDNA library and we selected for cells surviving after the induction of Bax. This genetic screen allows for the identification of plant genes, which inhibit either directly or indirectly the lethal phenotype of Bax. Using this method a number of cDNA clones were isolated, the more potent of which encodes a protein homologous to the class theta glutathione S-transferases. This Bax-inhibiting (BI) protein was expressed in Escherichia coli and found to possess glutathione S-transferase (GST) and weak glutathione peroxidase (GPX) activity. Expression of Bax in yeast decreases the intracellular levels of total glutathione, causes a substantial reduction of total cellular phospholipids, diminishes the mitochondrial membrane potential, and alters the intracellular redox potential. Co-expression of the BI-GST/GPX protein brought the total glutathione levels back to normal and re-established the mitochondrial membrane potential but had no effect on the phospholipid alterations. Moreover, expression of BI-GST/GPX in yeast was found to significantly enhance resistance to H(2)O(2)-induced stress. These results underline the relationship between oxidative stress and Bax-induced death in yeast cells and demonstrate that the yeast-based genetic strategy described here is a powerful tool for the isolation of novel antioxidant and antiapoptotic genes.

Acid-base equilibrium during capnoretroperitoneoscopic nephrectomy in patients with end-stage renal failure: a preliminary report.

We have studied the acid-base equilibrium in 12 patients with end-stage renal failure (ESRF) during capnoretroperitoneoscopic nephrectomy. Bupivacaine (12 mL, 0.375%) and morphine (2mg) were given in the lumbar epidural space, and fentanyl (0.5 microg kg(-1)) and midazolam (50 microg kg(-1)) were given intravenously. Anaesthesia was induced by thiopental, maintained with halothane carried by oxygen enriched air (inspired oxygen fraction = 0.35), and ventilation was achieved with a tidal volume of 10 mL kg(-1) at a rate of 12 min(-1). This procedure resulted in a mild degree of respiratory acidosis that was cleared within 60 min. We conclude that capnoretroperitoneoscopic nephrectomy can be performed in patients with end-stage renal failure with minimal transient respiratory acidosis that can be avoided by increased ventilation.

Perioperative renal protection in patients with obstructive jaundice using drug combinations.

BACKGROUND/AIMS: The effectiveness of dopamine alone or in combination with mannitol or furosemide in preventing postoperative renal dysfunction in patients with obstructive jaundice was assessed in this study. METHODOLOGY: Forty patients having obstructive jaundice were randomly allocated into 4 equal groups. Preoperative hydration was performed by infusing all patients 1L of 5% dextrose the night before surgery and another 1L in the morning before surgery. Intra- and postoperative maintenance of adequate intravascular volume was assured by fluid and blood replacement guided by the monitoring of central venous pressure urine output and blood pressure. The 1st group was kept as a control. The other 3 groups received dopamine 2.5 micrograms/kg/min for 2 postoperative days starting before surgery. The 2nd group was maintained on dopamine alone, while mannitol (0.25 g/kg), every 12 hours for 2 postoperative days, was added to the 3rd group. Similarly furosemide (1 mg/kg) every 12 hours for 2 postoperative days, was infused to the patients of the 4th group. Postoperative renal functions were assessed by 24-hour urine output, serum creatinine, creatinine clearance and urine to plasma osmolality ratio. RESULTS: All these tests did not show significant changes in the 1st, 2nd and 7th postoperative days. Only transient decreased creatinine clearance and elevated serum creatinine were observed in the patients of the 4th group in the 1st and 2nd postoperative days. This may be attributed to fluid imbalance induced by furosemide in these patients who were older than the other groups. CONCLUSIONS: The study showed that careful attention to perioperative hydration is the cornerstone in preserving adequate renal function following surgery in patients with obstructive jaundice. Administration of dopamine alone or in combination with mannitol or furosemide did not confer more renal protection.

Does spinal anesthesia affect cerebral oxygenation during transurethral prostatectomy?

BACKGROUND AND OBJECTIVES: Transurethral resection of the prostate (TURP) is associated with the unique complication of transurethral resection of prostate syndrome (TURS), which is attributed to the absorption of irrigating fluid. This study was initiated to investigate the effects of spinal anesthesia and TURP on cerebral oxygen balance. METHODS: Thirty patients scheduled for TURP were included. Jugular bulb oxygen saturation (SjbO2) was measured via retrograde cannulation of jugular venous bulb. Spinal anesthesia was initiated by 3 mL hyperbaric 0.5% bupivacaine injected at L3-L4 in the sitting position, producing a block to the T10 dermatome. Hemodynamic measurements and arterial and jugular bulb blood gasometry were performed before and after spinal anesthesia, throughout surgery, and during the postoperative period. RESULTS: A significant decrease of cerebral perfusion pressure after spinal anesthesia was accompanied by a significant decrease of SjbO2 below a preoperative value of 61% +/- 1. Eight patients developed yawning, irritability, restlessness, and nausea toward the end of surgery, and these were considered to be early signs of TURS. These patients demonstrated SjbO2 below 55% and 50% in 63% and 42% of respective data set points. CONCLUSION: The neurologic symptoms in patients undergoing TURP during spinal anesthesia might not only be caused by absorption of irrigating fluid but also by impairment of cerebral oxygenation.

Morphine-midazolam combination doses for presurgical analgesia in children.

We have examined the use of presurgical morphine-midazolam combination in 80 children aged 2-10 y undergoing repair of hypospadias. They were allocated randomly, in a double-blind study, to receive one of four morphine-midazolam combination doses (n = 20 each); (group I: 75 microg/kg each) [corrected] (group II: 75 microg/kg [corrected] morphine, 50 microg/kg [corrected] midazolam); (group III: 50 microg/kg [corrected] morphine, 75 microg/kg [corrected] midazolam); (group IV: 50 microg/kg [corrected] each). Drugs were given after induction of anesthesia and before the start of surgery. Observational scoring system, using crying, movement, agitation, posture and localization of pain as scoring criteria, was used to assess the children during their stay in the recovery room together with their sedative and/or analgesic requirement. Pre-surgical morphine-midazolam administration produced stable hemodynamic variables with satisfactory postoperative analgesia suggesting 75 microg/kg [corrected] dose of both morphine and midazolam as upper permissible dose, and 50 microg/kg [corrected] each as lower effective dose.

Pectin with low molecular weight and high degree of esterification increases absorption of 58Fe in growing rats.

Effects of pectins with different degrees of esterification (DE) and molecular weights (MW) on iron bioavailability were investigated in healthy growing rats by following erythrocyte incorporation of a dose of 58Fe. Rats were fed a control diet for 8 d and then deprived of food for 16 h. Two hours after the start of feeding iron-deficient diets, with or without pectin (80 g/kg diet), a dose of FeSO4 rich in 58Fe (60.28%) was intubated into the stomach; rats were then allowed to feed for an additional 4 h before withdrawal of food for 10 h. Rats were then fed iron-adequate diets for 9 d. The pectins differed in DE and MW, respectively, as follows: P-A (73%, 860,000), P-B (75%, 89,000), P-C (22%, 1,260,000) and P-D (24%, 114,000). Rats fed pectin-free diet with free access to food or restricted to the same quantity consumed by a respective pectin group served as controls. Iron absorption was 48% in the control group and 57% in rats fed P-B. Rats fed P-B had higher (P 2 < or = 0.05) serum iron, transferrin saturation, hematocrit and liver and spleen iron than the control group or the group fed P-C. These indices, except for transferrin saturation, were also higher In rats fed P-A and P-D compared with those fed P-C and controls, but to a lesser extent than in rats fed P-B. The data indicate that bioavailability of dietary non-heme iron was enhanced when pectin of low MW and high DE was added to the diet. This improvement was not evident with pectins having high MW and/or low DE.

Plasma bupivacaine concentrations following epidural administration in kidney transplant recipients.

BACKGROUND AND OBJECTIVE: The typical hemodynamic and biochemical characteristics of kidney transplant recipients may influence the pharmacokinetic profile of bupivacaine following its epidural administration. The objective of this study was to test this hypothesis in kidney transplant recipients compared with kidney surgery patients. METHODS: In a prospective open comparative study, 10 kidney transplant recipients and 10 kidney surgery patients received bupivacaine by the lumbar epidural route during the course of their operations. Arterial blood sampling was carried out before administration of bupivacaine and at 2, 5, 10, 15, 20, 25, 30 minutes and subsequently at 1, 1.5, 2, 4, 8, and 24 hours, after its administration. RESULTS: The calculated pharmacokinetic variables did not show any significant difference between the two groups. CONCLUSIONS: Lumbar epidural administration of bupivacaine is not associated with higher plasma bupivacaine concentrations in kidney transplant recipients than in nonuremic patients undergoing kidney surgery.

Hemodynamic and oxygenation variables during radical cystectomy. Does the anesthetic technique really matter?

The effect of anesthetics on hemodynamic variables (HV) has been clarified, but ambiguity existed concerning their effect on oxygenation variables (OV). Radical cystectomy provided a clinical setting for studying the effect of anesthetics on perioperative HV and OV. Patients subjected to radical cystectomy (n = 33) were assigned through balanced randomization to receive one of four anesthetic modalities, namely; group I: inhalation anesthesia using N2O:O2, halothane, d-tubocurarine (n = 11); group II: inhalation anesthesia using N2O:O2, halothane, d-tubocurarine, and supplemented with epidural analgesia (EA) (n = 11); group III: total intravenous anesthesia (TIVA) using ketamine 10-30 ug.kg-1.min-1, propofol 2 mg.kg-1.h-1, d-tubocurarine, and supplemented with continuous EA (n = 6): and group IV:TIVA using ketamine 20-50 ug.kg-1.min-1, midazolam in increments of 1.5 to 5 mg, and supplemented with intermittent EA (n = 5). Monitoring entailed continuous ECG, pulse oximerty, invasive arterial pressure, and pulmonary artery catheter for HV (HR, MAP, PAP, PAOP, CO, SVR, and PVR) and OV. (PaO2, SaO2, PvO2, SvO2, a-vDO2, O2ext, Qs/Qt, DO2, and VO2). The heart rate was lower in TIVA while other HV did not show striking differences, Group I showed higher arterial oxygen tension than group II and IV. Mixed venous oxygen tension and saturation were higher in group I over group IV. Other OV did not show remarkable differences. In conclusion, HV and OV in 4 anesthetic modalities did not elicit striking differences.