Effect of a liberal versus a restrictive pre-donation blood pressure policy on whole-blood donor adverse reactions.

BACKGROUND AND OBJECTIVES: The role of pre-donation blood pressure (BP) as independent contributor to post-donation vasovagal reactions (VVRs) is still debated. Differences between a liberal (i.e., inclusion of hypotensive donors) and a restrictive policy (i.e., not accepting hypotensive donors) should be investigated. This study aims to investigate the consequences of a liberal policy in development of VVRs after whole-blood donations. MATERIALS AND METHODS: We compared the incidence of VVRs between 2015 (restrictive policy) and 2016 (liberal policy) and the associated risk factors. We evaluated respectively 22 789 vs. 21 676 blood donations obtained from 18 001 blood donors (12 501 donated in both years). RESULTS: Comparing the results we obtained between 2015 and 2016, donations showed an overlap of the cohorts. Two hundred fifteen VVRs (incidence rate 0·48%) were observed, 104 (0·46%) of which in 2015, and 111 (0·51%) in 2016. A preliminary univariate analysis showed that donors with systolic BP <110 mm Hg had a two-fold risk of VVRs compared to normotensive donors (VVR/donation rate of 0·99% vs. 0·46%; P = 0·001). The subsequent multivariable logistic regression model showed that VVRs were highly associated with weight, site of collection, age and number of donations, excluding a role for systolic and diastolic BP. CONCLUSION: A liberal pre-donation BP policy seems to be safe for blood donors. Our analysis confirms that older donors with higher body-weight who already had donated blood are unlikely to experience VVRs.

No change in the regional distribution of tidal volume during lateral posture in mechanically ventilated patients assessed by electrical impedance tomography.

We assessed the distribution of regional lung ventilation during moderate and steep lateral posture using electrical impedance tomography (EIT) in mechanically ventilated patients. Seven patients were placed on a kinetic treatment table. An elastic belt containing 16 electrodes was placed around the chest and was connected to the EIT device. Patients were moved to left and right lateral positions in a stepwise (10 degrees ) mode up to 60 degrees. EIT images [arbitrary units (AU)] were generated and scanned for assessment of relative ventilation distribution changes [tidal volume (V(T))]. A calibration procedure of arbitrary units (AUs) versus ventilator-derived V(T) performed in all patients during three predefined positions (supine, 60 degrees-left dependent and 60 degrees-right-dependent) showed a significant correlation between V(T) in supine, left and right lateral positions with the corresponding AUs (r(2) = 0.356, P<0.05). Changes in V(T) were calculated and compared to supine position, and specific regions of interest (ROIs) were analysed. In our study, in contrast to recent findings, a change in lateral positions did not induce a significant change in regional tidal volume distribution. In right lateral positions, a broader variation of V(T) with a trend towards an increase in the dependently positioned lung was observed in comparison with supine. Lateral positioning promotes the redistribution of ventilation to the ventral regions of the lung. The use of EIT technology might become a helpful tool for understanding and guiding posture therapy in mechanically ventilated patients.

Comparison of cardiac, hepatic, and renal effects of arginine vasopressin and noradrenaline during porcine fecal peritonitis: a randomized controlled trial.

INTRODUCTION: Infusing arginine vasopressin (AVP) in vasodilatory shock usually decreases cardiac output and thus systemic oxygen transport. It is still a matter of debate whether this vasoconstriction impedes visceral organ blood flow and thereby causes organ dysfunction and injury. Therefore, we tested the hypothesis whether low-dose AVP is safe with respect to liver, kidney, and heart function and organ injury during resuscitated septic shock. METHODS: After intraperitoneal inoculation of autologous feces, 24 anesthetized, mechanically ventilated, and instrumented pigs were randomly assigned to noradrenaline alone (increments of 0.05 microg/kg/min until maximal heart rate of 160 beats/min; n = 12) or AVP (1 to 5 ng/kg/min; supplemented by noradrenaline if the maximal AVP dosage failed to maintain mean blood pressure; n = 12) to treat sepsis-associated hypotension. Parameters of systemic and regional hemodynamics (ultrasound flow probes on the portal vein and hepatic artery), oxygen transport, metabolism (endogenous glucose production and whole body glucose oxidation derived from blood glucose isotope and expiratory 13CO2/12CO2 enrichment during 1,2,3,4,5,6-13C6-glucose infusion), visceral organ function (blood transaminase activities, bilirubin and creatinine concentrations, creatinine clearance, fractional Na+ excretion), nitric oxide (exhaled NO and blood nitrate + nitrite levels) and cytokine production (interleukin-6 and tumor necrosis factor-alpha blood levels), and myocardial function (left ventricular dp/dtmax and dp/dtmin) and injury (troponin I blood levels) were measured before and 12, 18, and 24 hours after peritonitis induction. Immediate post mortem liver and kidney biopsies were analysed for histomorphology (hematoxylin eosin staining) and apoptosis (TUNEL staining). RESULTS: AVP decreased heart rate and cardiac output without otherwise affecting heart function and significantly decreased troponin I blood levels. AVP increased the rate of direct, aerobic glucose oxidation and reduced hyperlactatemia, which coincided with less severe kidney dysfunction and liver injury, attenuated systemic inflammation, and decreased kidney tubular apoptosis. CONCLUSIONS: During well-resuscitated septic shock low-dose AVP appears to be safe with respect to myocardial function and heart injury and reduces kidney and liver damage. It remains to be elucidated whether this is due to the treatment per se and/or to the decreased exogenous catecholamine requirements.

Hemodynamic, metabolic, and organ function effects of pure oxygen ventilation during established fecal peritonitis-induced septic shock.

OBJECTIVE: To test the hypothesis whether pure oxygen ventilation is equally safe and beneficial in fully developed fecal peritonitis-induced septic shock as hyperoxia initiated at the induction of sepsis. DESIGN: Prospective, randomized, controlled, experimental study with repeated measures. SETTING: Animal research laboratory at a university medical school. SUBJECTS: Twenty anesthetized, mechanically ventilated, and instrumented pigs. INTERVENTIONS: Twelve hours after induction of fecal peritonitis by inoculation of autologous feces, swine, which were resuscitated with hydroxyethyl starch and norepinephrine to maintain mean arterial pressure at baseline values, were ventilated randomly with an Fio2 required to keep Sao2 >90% (controls: n = 10) or Fio2 1.0 (hyperoxia, n = 10) during the next 12 hrs. MEASUREMENTS AND MAIN RESULTS: Despite similar hemodynamic support (hydroxyethyl starch and norepinephrine doses), systemic and regional macrocirculatory and oxygen transport parameters, hyperoxia attenuated pulmonary hypertension, improved gut microcirculation (ileal mucosal laser Doppler flowmetry) and portal venous acidosis, prevented the deterioration in creatinine clearance (controls 61 (44;112), hyperoxia: 96 (88;110) mL.min(-1), p = .074), and attenuated the increase in blood tumor necrosis factor-alpha concentrations (p = .045 and p = .112 vs. controls at 18 hrs and 24 hrs, respectively). Lung and liver histology (hematoxyline eosine staining) were comparable in the two groups, but hyperoxia reduced apoptosis (Tunel test) in the liver (4 (3;8) vs. 2 (1;5) apoptotic cells/field, p = .069) and the lung (36 (31;46) vs. 15 (13;17) apoptotic cells/field, p < .001). Parameters of lung function, tissue antioxidant activity, blood oxidative and nitrosative stress (nitrate + nitrite, 8-isoprostane levels; deoxyribonucleic acid (DNA) damage measured using the comet assay) were not further affected during hyperoxia. CONCLUSIONS: When compared with the previous report on hyperoxia initiated simultaneously with induction of sepsis, i.e., using a pretreatment approach, pure oxygen ventilation started when porcine fecal peritonitis-induced septic shock was fully developed proved to be equally safe with respect to lung function and oxidative stress, but exerted only moderate beneficial effects.

Malariological baseline survey and in vitro antimalarial drug resistance in Gulu district, Northern Uganda.

A comprehensive, representative malaria survey has been carried out in a population of internally displaced persons (IDP) in the district of Gulu, Northern Uganda. It included 74 households and 390 persons, and covered socio-economic and environmental information, individual physical data, malaria and the drug sensitivity of Plasmodium falciparum. The prevalence of infections with Plasmodium falciparum was 54.4% at a geometric mean asexual parasitaemia of 229/microl blood, typical for hyperendemic conditions. P. falciparum turned out to be highly resistant to chloroquine and amodiaquine. It showed also reduced sensitivity against lumefantrine and artemisinin, obviously the result of the liberal use of the lumefantrine-artemether combination without evidence-based indication.

Ultrasound-guided versus computed tomography-controlled facet joint injections in the lumbar spine: a prospective randomized clinical trial.

BACKGROUND AND OBJECTIVES: Facet joint injections are widely used for alleviation of back pain. Injections are preferentially performed as fluoroscopy or computed tomography (CT)-controlled interventions. Ultrasound provides real-time monitoring, does not produce ionizing radiation, and is broadly available. METHODS: We studied feasibility, accuracy, time-savings, radiation doses, and pain relief of ultrasound-guided facet joint injections versus CT-controlled interventions in a prospective randomized clinical trial. Forty adult patients with chronic low back pain were consecutively enrolled and evenly assigned to an ultrasound or a CT- group. RESULTS: Eighteen subjects from the group randomized to ultrasound were judged to be feasible for this type of approach. In 16 of them the facet joints were clearly visible and all of the associated facet joint injections were performed correctly. The duration of procedure and radiation dose was 14.3 +/- 6.6 minutes and 14.2 +/- 11.7 mGy.cm in the ultrasound group, and 22.3 +/- 6.3 minutes and 364.4 +/- 213.7 mGy.cm in the CT group. Both groups showed a benefit from facet joint injections. CONCLUSIONS: The ultrasound approach to the facet joints in the lumbar spine is feasible with minimal risks in a large majority of patients and results in a significant reduction of procedure duration and radiation dose.

Ultrasound-guided facet joint injections in the middle to lower cervical spine: a CT-controlled sonoanatomic study.

OBJECTIVES: The aim of this study was to investigate the efficacy of ultrasound as a guiding tool for simulated cervical facet joint injections in cadavers. METHODS: A total of 40 ultrasound examinations at 5 levels (C6-7 to C2-3) were performed on 4 embalmed cadavers. The zygapophyseal joints were located with ultrasound. First, the transverse processes of C6 and C7 were established and the facet joint of C6-7 was demonstrated. The midpoint of this joint space, defined as the middle of its cranio-caudal extension on its lateral surface, was taken as a reference point. Ipsilateral distances (A, B, C, and D) between this point and each one of the 4 facet joints of the cervical spine up to the facet joints C2-3 were then computed. Subsequently, coronal computed tomography (CT) scans were taken to verify these distances. In a second experiment, a spinal needle was advanced under ultrasound guidance to the zygapophyseal joints from C2-3 to C6-7 on both sides of 1 cadaver. The exact placement of the needle tips was again verified by CT. RESULTS: In 4 attempts, a depiction of the joint space was not possible. Ultrasound and CT provided the same mean measurements of 1.2+/-0.2 cm, 2.0+/-0.3 cm, 3.0+/-0.2, and 4.0+/-0.5 cm for distances A, B, C, and D, respectively. All 10 needle tips were located in the joint space during simulated facet joint injections, as also verified by CT. DISCUSSION: This preclinical study suggests that ultrasound is a useful guiding tool for facet joint injections in the cervical spine.

Genetic structure in contemporary south Tyrolean isolated populations revealed by analysis of Y-chromosome, mtDNA, and Alu polymorphisms.

Most of the inhabitants of South Tyrol in the eastern Italian Alps can be considered isolated populations because of their physical separation by mountain barriers and their sociocultural heritage. We analyzed the genetic structure of South Tyrolean populations using three types of genetic markers: Y-chromosome, mitochondrial DNA (mtDNA), and autosomal Alu markers. Using random samples taken from the populations of Val Venosta, Val Pusteria, Val Isarco, Val Badia, and Val Gardena, we calculated genetic diversity within and among the populations. Microsatellite diversity and unique event polymorphism diversity (on the Y chromosome) were substantially lower in the Ladin-speaking population of Val Badia compared to the neighboring German-speaking populations. In contrast, the genetic diversity of mtDNA haplotypes was lowest for the upper Val Venosta and Val Pusteria. These data suggest a low effective population size, or little admixture, for the gene pool of the Ladin-speaking population from Val Badia. Interestingly, this is more pronounced for Ladin males than for Ladin females. For the pattern of genetic Alu variation, both Ladin samples (Val Gardena and Val Badia) are among the samples with the lowest diversity. An admixture analysis of one German-speaking valley (Val Venosta) indicates a relatively high genetic contribution of Ladin origin. The reduced genetic diversity and a high genetic differentiation in the Rhaetoroman- and German-speaking South Tyrolean populations may constitute an important basis for future medical genetic research and gene mapping studies in South Tyrol.

An unusual cause of sepsis during pregnancy: recognizing infection with chlamydophila abortus.

BACKGROUND: Chlamydophila abortus (formerly Chlamydia psittaci serovar 1) is a rare but severe cause of gestational septicemia, with particular problems in diagnosis and clinical management. CASE: A 32-year-old woman in her fourth pregnancy (16th week of gestation) presented with progressive septicemia after extensive contact with abortive material from her goat flock. Treatment with levofloxacin could not prevent abortion. Multiorgan failure requiring catecholamines and artificial ventilation developed in the patient. After the agent was identified by polymerase chain reaction from acute-phase serum, macrolides were administered and yielded clinical improvement. The patient fully recovered. There were no sequelae in the subsequent 6 months. CONCLUSION: Cp abortus must be considered in gestational septicemia after contact with ruminants. Polymerase chain reaction from acute-phase serum is a quick and easy way to establish the diagnosis. Macrolide antibiotics are still the treatment of choice.

Plasma disappearance of indocyanine green: a marker for excretory liver function?

OBJECTIVE: To investigate whether the plasma disappearance rate of indocyanine green (ICG) assessed using a commercially available bedside monitor provides an accurate estimation of cumulative biliary ICG excretion in a clinically relevant model of long-term, hyperdynamic porcine endotoxemia. DESIGN AND SETTING: Prospective experimental study in the animal laboratory in a university hospital. SUBJECTS: Fifteen domestic pigs. INTERVENTIONS: Pigs were anesthetized, mechanically ventilated, and instrumented. Intravenous endotoxin was continuously infused over 12 h concomitant with fluid resuscitation. Measurements were performed before and 12 h after the start of endotoxin infusion. MEASUREMENTS AND RESULTS: All animals developed hyperdynamic circulation characterized by a sustained increase in cardiac output. Despite well maintained portal venous and consequently total liver blood flow endotoxemia decreased hepatic lactate uptake, which was accompanied by a significant fall in portal and hepatic venous pH. Both the cumulative bile flow and biliary ICG and bicarbonate excretion measured during 1 h after intravenous bolus of 25 mg ICG fell significantly. By contrast, neither the plasma disappearance rate of ICG nor the rate corrected for liver blood flow exhibited any changes over time. CONCLUSIONS: In hyperdynamic porcine endotoxemia the plasma disappearance rate of ICG failed to accurately substitute for direct short-term measures of biliary ICG excretion. Hence normal values of plasma disappearance rate of ICG should be interpreted with caution in early, acute inflammatory conditions.

Ultrasound-guided periradicular injections in the middle to lower cervical spine: an imaging study of a new approach.

BACKGROUND AND OBJECTIVES: The objective of this study was to show the efficacy of ultrasound in facilitating the performance of a simulated cervical periradicular injection in cadavers. METHODS: A total of 40 ultrasound-guided examinations at 4 levels (C3 to C7) were performed on 4 embalmed cadavers. The cervical spinal nerves were located with ultrasound. First, the transverse process of each level was taken as a sonoanatomic landmark. The most lateral aspect of the transverse process of the seventh cervical vertebra was then established as the reference point. Ipsilateral distances (A, B, C, and D) between this point and each one of the transverse processes of the cervical spine up to the third vertebra were then computed. Subsequently, coronal computed tomography (CT) scans were taken to verify these distances. In a second part, a spinal needle was advanced under ultrasound guidance to the spinal nerves C5 to C8 on both sides of one cadaver. The exact placement of the needle tips was checked by CT. RESULTS: The transverse processes were identified in all cadavers. In 5 attempts, a depiction of the spinal nerves was not possible. Ultrasound and CT provided the same mean measurements of 1.1 cm, 2.1 cm, 3.1 cm, and 4.1 cm for distances A, B, C, and D, respectively. All 8 needle tips were placed within 5 mm dorsal to the spinal nerve and less than 5 mm away from the posterior tubercle of each level's transverse process, as also verified by CT. CONCLUSIONS: This preclinical study suggests that ultrasound is a useful guiding tool for periradicular injections in the cervical spine.

Ultrasound guidance for facet joint injections in the lumbar spine: a computed tomography-controlled feasibility study.

UNLABELLED: We conducted this study to develop an ultrasound-guided approach for facet joint injections of the lumbar spine. Five zygapophyseal joints (L1-S1) on each side of 5 embalmed cadavers were examined by ultrasound for a total of 50 examinations. The joint space was demonstrated under ultrasound guidance. The midpoint of the joint space, defined as the middle of its cranio-caudal extension on its dorsal surface, was taken as a reference point, and its position was computed from its depth and lateral distance from the spinous process. Forty-two of 50 approaches could be clearly visualized. Subsequently, these distances were compared to those obtained by computed tomography (CT). To assess the efficacy of ultrasound in the needle placement, all lumbar facet joints were approached in one embalmed cadaver. The exact placement of the needle tips was again evaluated by CT. Ultrasound and CT measurements showed the same mean depth and lateral distance to the reference point, 3.15 +/- 0.5 cm and 1.9 +/- 0.6 cm, respectively. Pearson's coefficient of correlation was 0.86 (P < 0.0001) between ultrasound and CT. All 10 needle tips were within the joint space during simulated facet joint injections. We conclude that ultrasound guidance might be a useful adjunct for facet joint injections in the lumbar spine. IMPLICATIONS: This study was designed to develop an ultrasound-guided approach to the facet joints of the lumbar spine and to assess its feasibility and accuracy by means of a comparison to computed tomography images. The imaging study demonstrated a significant correlation between ultrasound and computed tomography measurements. During simulated facet injection, ultrasound guidance consistently resulted in accurate needle placement.

Real-time sonographic imaging for periradicular injections in the lumbar spine: a sonographic anatomic study of a new technique.

OBJECTIVE: We conducted this study to develop a sonographically guided approach to the spinal nerve of the lumbar spine and to assess its feasibility and accuracy by means of computed tomography (CT). METHODS: Fifty sonographically guided approaches at 5 levels (L1-S1) were performed on 5 embalmed cadavers, which were positioned prone. The spinal nerves of the lumbar spine were shown under sonographic guidance. In 1 cadaver, the most lateral aspect of the roof of the intervertebral foramen was defined as a reference point. Its position was computed as a distance from the tip of the spinal process (A), the midline (B), and the intervertebral disk (C). Subsequently, axial transverse CT scans were made to verify these distances. In a second part of the experiment, a spinal needle was advanced under sonographic guidance to the spinal nerves for each lumbar spinal level on 1 embalmed cadaver. The exact placement of the needle tips was checked with the help of CT. RESULTS: This technique for a sonographically guided approach to the periradicular area proved to be feasible and accurate. Sonography and CT provided the same mean measurements of 4.0, 2.5, and 1.4 cm for distances A, B, and C, respectively. The Pearson correlation coefficient was 0.99 (P < .001) between sonography and CT. In the experimental study, all 10 needle tips were placed periradicular to the spinal nerves. CONCLUSIONS: Sonographic guidance is a useful adjunct to increase the safety and efficacy of periradicular injections in the lumbar spine.

Adenosine triphosphate-magnesium dichloride during hyperdynamic porcine endotoxemia: effects on hepatosplanchnic oxygen exchange and metabolism.

OBJECTIVE: To assess the effects of adenosine triphosphate-magnesium dichloride (ATP-MgCl2) on systemic and hepatosplanchnic hemodynamics, oxygen exchange, and energy metabolism over 24 hrs of hyperdynamic normotensive porcine endotoxemia. DESIGN: Prospective, randomized, controlled experimental study with repeated measures. SETTING: Investigational animal laboratory. SUBJECTS: Seventeen pigs were divided into two groups: eight animals receiving endotoxin served as a control group and nine animals received endotoxin (lipopolysaccharide) and ATP-MgCl2. INTERVENTIONS: Pigs were anesthetized, mechanically ventilated, and instrumented. Endotoxemia was achieved by continuous intravenous infusion of Escherichia coli lipopolysaccharide. Animals were resuscitated by hetastarch targeted to maintain mean arterial pressure of >75 mm Hg. Twelve hours after the start of the endotoxin infusion, ATP-MgCl2, or its vehicle, were administered for 12 hrs. MEASUREMENTS AND MAIN RESULTS: Mean arterial pressure was maintained in the control group because of a sustained increase in cardiac output achieved by fluid resuscitation, whereas ATP-MgCl2 significantly decreased mean arterial pressure because of further systemic vasodilatation. ATP-MgCl2 markedly increased portal venous flow. In contrast to the controls, hepatic arterial flow remained unchanged until the end of the experiment, despite the further increase in cardiac output. The ileal mucosal-arterial PCO2 gap (Delta PCO2) progressively increased (p <.05) in control animals, whereas it was restored to prelipopolysaccharide levels during ATP-MgCl2 infusion. Changes in Delta PCO2 correlated with those of portal vein blood flow in these animals (r = -.68, p <.05). Moreover, ATP-MgCl2 blunted the lipopolysaccharide-induced decrease in hepatic lactate balance but did not affect portal venous pH, hepatosplanchnic oxygen exchange, splanchnic lactate/pyruvate ratios, isoprostane, NO2- + NO3-, cytokine concentrations, or tissue nucleotide content. CONCLUSION: During long-term hyperdynamic porcine endotoxemia, ATP-MgCl2 normalized the otherwise progressive rise of the ileal mucosal-arterial Delta PCO2. Furthermore, it allowed blunting of the continuous decrease in hepatic lactate clearance, thus preserving the metabolic coupling between lactate release from the intestine and lactate utilization by the liver.

Inhaling nitrous oxide or xenon does not influence bowel wall energy balance during porcine bowel obstruction.

UNLABELLED: Xenon (Xe) is less soluble than nitrous oxide (N(2)O) and hence may be more suitable during bowel obstruction. Therefore, we compared the intestinal mechanical and biochemical effects of these two gases with those of total IV anesthesia in a porcine model of small-bowel obstruction. Intestinal obstruction was induced in 33 anesthetized pigs, in 18 of which segmental ileal perfusion was reduced by partial arterial occlusion. Pigs received total IV anesthesia, Xe, or N(2)O (in 30% oxygen) for 4 h, and we determined the intraluminal pressure and volume, the arterial-ileal PCO(2) gap, and the lactate and pyruvate levels in the segmental mesenteric vein. Under both experimental conditions, Xe or N(2)O ventilation caused the volume to significantly increase with a concomitant significant increase in the intraluminal pressure during N(2)O ventilation. Regardless of the anesthesia technique, none of the biochemical variables was influenced in the animals with maintained ileal blood supply. In contrast, reducing the segmental perfusion induced pronounced alterations of all variables of bowel wall energy metabolism. The type of anesthesia, however, had no further statistically significant effect. Short-term inhalation of Xe or N(2)O seems to have no deleterious effects on the metabolic balance of the gut wall during intestinal obstruction. IMPLICATIONS: In anesthetized pigs, short-term inhalation of xenon or nitrous oxide over 4 h when compared with total IV anesthesia had no additional deleterious effects on the metabolic balance of the gut wall during intestinal obstruction, no matter whether the arterial blood flow was reduced or not.