Water droplet evaporation in varied gravity and electric fields

Sessile water droplet evaporation in varied gravity and electric fields has been experimentally studied. Specifically, the influences of gravity and electric fields are investigated in the context of the heat flux distribution beneath the droplets, as well as the droplet mechanics and resulting shapes. Experimental testing was carried out during a European Space Agency (ESA) Parabolic Flight Campaign (PFC 66). The droplets tested evaporated with a pinned contact line, a single wettability condition, and varied droplet volume and substrate heat flux. The peak heat transfer was located at the contact line for all cases. The peak heat flux, average heat flux, and droplet evaporation rate were shown to vary strongly with gravity, with higher values noted for hypergravity conditions and lower values in microgravity conditions. The droplet thermal inertia was shown to play a significant role, with larger droplets taking more time to reach thermal equilibrium during the parabolic testing period. No significant impact of the electric field on the droplet evaporation was noted for these test conditions.

Bubble growth analysis during subcooled boiling experiments on-board the international space station: Benchmark image analysis

This work compares four different image processing algorithms for the analysis of image data obtained during the Multiscale Boiling Experiment of ESA, executed on-board the International Space Station. Two separate experimental campaigns have been performed in 2019 and 2020, aiming to investigate boiling phenomena in microgravity, with and without the presence of shear flow and electric field. A heated substrate, at the bottom of the test cell, creates a temperature profile across the liquid bulk above it. A laser beam hits a designated microcavity at the middle of the substrate, to initiate nucleation of a single, isolated bubble. In the presence of shear flow or electric field forces, the bubble slides or detaches respectively, leaving the cavity free for the nucleation and growth of a new bubble. The growth of such a bubble within the prescribed temperature profile is studied for varying experimental conditions (i.e. pressure, heat flux, subcooling temperature) by capturing high speed, black and white video images. The presence of light reflections at random locations around the bubble contour vary with bubble size and population. This, combined with the refraction induced optical distortion of vertical image dimension close to the heater, make the accurate detection of bubbles contour a real challenge. Four research teams, namely the University of Pisa (UNIPI), the Institute of Fluid Mechanics of Toulouse (IMFT), the joint group of Aix Marseille University (AMU) and Kutateladze Institute of Thermophysics (IT), and the joined group of Aristotle University of Thessaloniki (AUTH), Technical University of Darmstadt (TUD) and Foundation of Research and Technology in Crete (FORTH), developed separate specialized algorithms to: a) detect bubble edges and b) use these edges to calculate basic bubble geometrical features, such as contact line diameter, bubble diameter and contact angles. These four different approaches diverge in complexity and concept. In the absence of reference measurements at microgravity conditions, measurements efficiency is evaluated based on the comparison of the estimated bubble geometrical features along with pertinent physical arguments. Results show that the efficiency of each approach varies with the nature of measurement. The studied benchmark dataset is published allowing other research groups to test further their own image processing algorithms.

Differentiation and characterization of rat adipose tissue mesenchymal stem cells into endothelial-like cells

In this study, mesenchymal stem cells were isolated from rat adipose tissue (AD-MSCs) to characterize and differentiate them into endothelial-like cells. AD-MSCs were isolated by mechanical and enzymatic treatments, and their identity was verified by colony-forming units (CFU) test and by differentiation into cells of mesodermal lineages. The endothelial differentiation was induced by plating another aliquot of cells in EGM-2 medium, enriched with specific endothelial growth factors. Five subcultures were performed. The expression of stemness genes (OCT4, SOX2 and NANOG) was investigated. The presence of CD90 and the absence of the CD45 were evaluated by flow cytometry. The endothelial-like cells were characterized by the evaluation of morphological changes and gene expression analysis for endothelial markers (CD31, CD144, CD146). Characterization of AD-MSCs showed their ability to form clones, to differentiate in vitro and the OCT-4, SOX-2, NANOG genes expression. Immunophenotypic characterization showed the CD90 presence and the CD45 absence. The endothelial-like cells showed morphological changes, the expression of CD31, CD144, CD146 genes and the presence of CD31 membrane receptor. Matrigel assay showed their ability to form network and vessels-like structures. This study lays the foundations for future evaluation of the potential AD-MSCs pro-angiogenic and therapeutic role.

Rett syndrome: a wide clinical and autonomic picture

Background

Rett Syndrome is a neurodevelopmental disorder almost exclusively affecting females, characterized by a broad clinical spectrum of signs and symptoms and a peculiar course. The disease affects different body systems: nervous, muscolo-skeletal, gastro-enteric. Moreover, part of the symptoms are related to the involvement of the autonomic nervous system.

In the Tuscany Rett Center at Versilia Hospital, we collected data from 151 subjects with a clinical diagnosis of classical or variant RTT syndrome. For each subject, we assessed the severity of the condition with clinical-rating scales (ISS, PBZ), we quantified the performance of the autonomic nervous system, and we performed genetic analysis. We used multivariate statistical analysis of the data to evaluate the relation between the different clinical RTT forms, the cardiorespiratory phenotype, the different genetic mutations and the severity of the clinical picture. Individuals were classified according to existing forms: Classical RTT and three atypical RTT: Z-RTT, Hanefeld, Congenital. A correlation between C-Terminal deletions and lower severity of the clinical manifestations was evident, in the previous literature, but, considering the analysis of autonomic behaviour, the original classification can be enriched with a more accurate subdivision of Rett subgroups, which may be useful for early diagnosis.

Results

Present data emphasize some differences, not entirely described in the literature, among RTT variants. In our cohort the Z-RTT variant cases show clinical features (communication, growth, epilepsy and development), well documented by specific ISS items, less severe, if compared to classical RTT and show autonomic disorders, previously not reported in the literature. In this form epilepsy is rarely present. In contrast, Hanefeld variant shows the constant presence of epilepsy which has an earlier onset In Hanefeld variant the frequency of apneas was rare and, among the cardiorespiratory phenotypes, the feeble type is lacking.

Conclusion

A quantitative analysis of the different autonomic components reveals differences across typical and atypical forms of RTT that leads to a more accurate classification of the groups. In our cohort of RTT individuals, the inclusion of autonomic parameter in the classification leads to an improved diagnosis at earlier stages of development.

Evidence for Tunisian-Like Pestiviruses Presence in Small Ruminants in Italy Since 2007

The genus Pestivirus, which belongs to the Flaviviridae family, includes ssRNA+ viruses responsible for infectious diseases in pigs, cattle, sheep, goats and other domestic and wild ruminants. Like most of the RNA viruses, pestivirus has high genome variability with practical consequences on disease epidemiology, diagnosis and control. In addition to the officially recognized species in the genus Pestivirus, such as BVDV-1, BVDV-2, BDV and CSFV, other pestiviruses have been detected. Furthermore, most of the ruminant pestiviruses show low or absent species specificity observed in serological tests and are able to infect multiple species. Particularly, small ruminants are receptive hosts of the most heterogeneous group of pestiviruses. The aim of this study was to carry out the molecular characterization of pestiviruses isolated from sheep and goats in Sicily, Italy. Phylogenetic analysis of two viral genomic regions (a fragment of 5'-UTR and the whole N^pro regions) revealed the presence of different pestivirus genotypes in the analysed goat and sheep herds. Two of five viral isolates were clustered with BVDV-1d viruses, a strain widespread in Italy, but never reported in Sicily. The other three isolates formed a distinct cluster with high similarity to Tunisian isolates, recently proposed as a new pestivirus species. This represents the first evidence for Tunisian-like pestivirus presence in small ruminants in Italy. Furthermore, one of the isolates was collected from a goat, representing the first isolation of Tunisian-like pestivirus from this species.

Total intravenous anesthesia using remifentanil in extracorporeal shock wave lithotripsy (ESWL). Comparison of two dosages: a randomized clinical trial

BACKGROUND

Extracorporeal Shock Wave Lithotripsy is usually performed in day surgery setting, consequently people who undergo to this procedure need a safe and fast recovery. Conscious sedation with remifentanil can relieve from pain and keep patients in touch with anaesthesiologists. Few publications tell about infusion rates administered to perform this procedure7. The aim of this study is to assess which is the most appropriate infusion rate.

METHODS

Patients were randomly assigned to two groups. Two different infusion rates were compared: 0,05 mcg/kg/min, GROUP A (N.=114), vs. 0.1 µg/kg/min, GROUP B (N.=114). Patients' vital signs, additional analgesic requests, PONV (postoperative nausea and vomiting) and other side effects were registered. The deepness of sedation and patient's satisfaction were evaluated referring to Obsever's Assessment of Alertness and Sedation scale (O/ASS) and using a Likert's scale respectively. Pain intensity was assessed with a 11-points VAS (visual analogue scale). Differences between groups were analyzed using Student t test for independent variables. The χ2 test was used to analyze categorical variables.

RESULTS

The study enrolled 228 patients and assigned them to two groups (N.=114). No significant differences were found regarding Likert's scale values (P=0.20), additional analgesic request (P=0.30) and mean VAS values (P>0.05) between the two groups. The difference between the two groups about PONV, hypotension, oxygen desaturation and respiratory depression was statistically significant (P<0.05), as a matter of fact in group A these side effects occurred less frequently. The fifth degree of O/ASS was estimated in about 1.61±0.19 min and 2.987±0.20 min in group A and in group B respectively (P<0.05).

CONCLUSION

According with previous results remifentanil at the infusion rate of 0.05 µg/kg/min provides an effective analgesia, causing a lower incidence of side effect than 0.1 µg/kg/min, granting a fast and safe recovery.

Safety and efficacy of transdermal buprenorphine and transdermal fentanyl in the treatment of neuropathic pain in AIDS patients

BACKGROUND

Multifactor neuropathic pain is one of the most frequent symptoms in AIDS patients and analgesic treatment is primarily based on the use of drug combination of opioids, tricyclic antidepressants and antiepileptics. However, the chronic use of opioids in AIDS patients presents a risk due to the immunosuppressive action of these drugs. Until now, buprenorphine has been regarded as one of the safest opioid analgesics for the treatment of patients with compromised immune systems. To assess the suitability of transdermal fentanyl for the treatment of neuropathic pain in AIDS patients, the present study compares the efficacy, tolerability and the immunosuppressive effects of transdermal buprenorphine vs. fentanyl.

METHODS

Forty advanced AIDS patients (28 male and 12 female) with chronic peripheral neuropathic pain were enrolled onto this clinical trial. Neuropathic pain was assessed for its constituent types of pain (burning, stabbing and shooting), its overall intensity and allodynia; scores were awarded using the Neuropathic Pain Scale, expressed as 10 item VAS scores.

RESULTS

Both treatment groups showed statistically significant reductions in each of the individual types of neuropathic pain and allodynia (P<0.05; 95% CI: -14.7, -3.1) and significant improvements in Karnofsky Performance Status (P<0.05; mean value, 69; range: 40-90). Both buprenorphine and fentanyl were well tolerated. Neither buprenorphine nor fentanyl affected CD4+ or CD8+levels and both treatments, but particularly buprenorphine group, resulted in more stable CD4+ concentrations.

CONCLUSION

The high efficacy, tolerability and patient compliance of both buprenorphine and fentanyl make both these two opioids valid therapeutic options for the treatment of neuropathic pain in patients with AIDS.

Neuromuscular block in Italy: a survey of current management

BACKGROUND

Little is known about current use of neuromuscular blocking agents by Italian anesthetists. This paper reports the results of a survey conducted to obtain information about current management of neuromuscular block in Italy.

METHODS

A questionnaire was given to Italian Anesthetists attending the 64nd National Congress of the Italian Society of Anesthesia, Intensive Care, Analgesia and Intensive Therapy S.I.A.A.R.T.I. (Parma, 13th-16th October 2010). Collected data were stratified by age, geographical location, and the total number of surgical procedures performed in the hospitals concerned.

RESULTS

One thousand four hundred forty patients correctly compiled questionnaires were collected. 50% of respondents used clinical tests to monitor the level of neuromuscular blockade. The main clinical tests cited for the evaluation were: keeping the head lifted up for 5 seconds, protruding the tongue and opening the eyes. Train-of-four was used by 50% of respondents on a routine basis. Only 33% of anesthetists reply that a train-of-four ratio of 90% or more is the safe level prior to extubation.

CONCLUSION

Clinical signs are used by most of the Italian anesthetists to assess the recovery from neuromuscular blockade. There is poor awareness about their inability to indicate even a significant degree of residual neuromuscular block. A more extensive use of quantitative instrumental monitoring is required for the more rational use of neuromuscular blocking agents.

Knowledge of residual curarization: an Italian survey

BACKGROUND

The use of neuromuscular blocking agents (NMBAs) is widespread in anesthetic practice; little is known about the current use of these drugs in Italy. This survey was conducted to obtain information about the most commonly used clinical tests and the train-of-four (TOF) ratios that are considered as being reliable for assessing recovery from neuromuscular blockade at the end of anesthesia and the estimated occurrence rates of post-operative paralysis in Italian hospitals.

METHODS

The questionnaire was given to Italian anesthesiologists attending the 62nd National Congress of the Italian Society of Anesthesia, Analgesia and Intensive Therapy. Collected data were stratified by age and the total number of surgical procedures performed in the hospitals concerned.

RESULTS

Seven hundred and fifty-four correctly compiled questionnaires were collected (response rate 88.7%). Seventy three percent of the respondents only used clinical tests for monitoring the level of neuromuscular blockade. The main clinical tests cited for the evaluation of residual paralysis were keeping the head lifted up for 5 s, protruding the tongue and opening the eyes. TOF was used by 35% of the respondents on a routine basis. Only 24% of the interviewed anesthesiologists reported that before extubation, a TOF ratio of at least 0.9 should be reached.

CONCLUSIONS

Most Italian anesthetists assess the recovery from neuromuscular blockade only by clinical signs. There is poor awareness about the inability of such techniques to indicate even a significant amount of residual neuromuscular block. A more extensive use of quantitative instrumental monitoring is required for the more rational use of NMBAs.

Measurement of the sensitivity of different commercial assays in the diagnosis of CMV infection in pregnancy

To evaluate the performance of different commercial assays for the detection of recent cytomegalovirus (CMV) in pregnancy, the sensitivity and specificity of assays for CMV-specific IgM antibodies were compared. Routine specimens from pregnant women were screened for CMV IgM using the Abbott AxSYM assay. Sera that were reactive according to AxSYM were further tested for IgM by other commercial assays. In selected IgM positive samples a CMV IgG avidity assay (Radim) and virus isolation from urine (shell vial) were also performed. The positivity rate for IgM anti-CMV by AxSYM was relatively high (140 out of 492, combining reactive and grayzone results). Only 26 of the 140 samples were positive for IgM according to Radim. The IgG avidity was low in 16 of the 43 samples tested, and the Radim and DiaSorin IgM assays were negative in 5 of them; 2 of the latter cases were also positive for viral isolation according to a shell vial method. There are differences in the sensitivity of the commercially available tests for CMV antibodies. CMV screening in pregnancy is performed as a first step by immunoassays and the choice of highly sensitive IgM test associated with further serological and virological methods could help to identify early primary infections.

Inhaled aerosolized prostaglandin E1, pulmonary hemodynamics, and oxygenation during lung transplantation

BACKGROUND

The use of inhaled aerosolized prostaglandin E(1) (aerPGE(1)), a pulmonary vasodilator, has not been widely analyzed. In contrast to prostacyclin, PGE(1) has a shorter lifetime and is metabolized in a greater amount from the lungs, lowering the risk of systemic effects. The aim of this study was to analyse the effects of aerPGE(1) administration on pulmonary hemodynamics and oxygenation during lung transplantation.

METHODS

Eighteen patients undergoing lung transplantation were enrolled in this study. During the first lung implantation, systemic and pulmonary hemodynamic and oxygenation data were evaluated in three phases: -- baseline in 100% O(2); during aerPGE(1) -- after 15 min of aerosolized prostaglandin E(1) administration in 100% O(2); after aerPGE(1) -- 15 min after the end of the prostaglandin E(1) administration in 100% O(2).

RESULTS

During aerPGE(1) a reduction in mPAP, PVRI, and Qs/Qt and an increase in PaO(2)/FiO(2) were observed. Soon after prostaglandin inhalation was ceased, the mPAP, the PVRI, and the Qs/Qt increased while PaO(2)/FiO(2) decreased. During the study, no significant difference in systemic pressure among the phases was noted. A high correlation between changes in mPAP, Qs/Qt and PaO(2)/FiO(2) after aerPGE(1) administration and baseline values was observed. ROC curve analysis showed that values of 40 mmHg of mPAP, 21.7% of the pulmonary shunt, and 364 mmHg for PaO(2)/FiO(2) predict a decrease in mean pulmonary arterial pressure and pulmonary shunt or an improvement in oxygenation of 10% with respect to baseline values.

CONCLUSION

A low dose of aerosolized prostaglandin E(1) decreases pulmonary arterial pressure and improves oxygenation without impairment on systemic hemodynamics, also during anesthesia for lung transplantation. The effect seems to depend on baseline values, which can be considered to be a predictor of the prostaglandin response.

Acute edema blisters in a hereditary angioedema cutaneous attack

Hereditary angioedema is a rare autosomal dominant disease characterized by recurrent episodes of acute edema affecting the skin and the respiratory and digestive tracts. Acute edema blisters or hydro-static bullae develop after rapid accumulation of interstitial fluid usually associated to cardiac insufficiency. Lesions contain sterile fluid and break up easily resolving without scars. Blisters disappear when fluid accumulation resolves. We describe a patient developing recurrent acute edema blisters as a consequence of cutaneous hereditary angioedema attacks.

Does circulating BNP normalize after heart transplantation in patients with normal hemodynamic and right and left heart functions?

BACKGROUND

Increased brain natriuretic peptide (BNP) in cardiovascular disease is thought to be a compensatory protective mechanism allowing to delay the occurrence of terminal heart failure. Heart transplantation should normalize the neuroendocrine balance but BNP remains elevated in stable heart-transplant recipients (Htx). Such increase has been related to persistent endothelial and cardiac dysfunctions. The purpose of this study was to determine whether selected Htx, presenting with normal hemodynamic and cardiac systolic and diastolic functions on both side of the heart, show a normalization of their BNP plasma values.

METHODS

Of a cohort of well-being 26 Htx, we selected 12 patients with normal hemodynamics and left and right heart systolic and diastolic functions and compared their circulating BNP, cyclic guanosine monophosphate (cGMP) (the BNP second messenger) and endothelin-1 (ET) values with that of 12 age-, body mass index- and mean arterial pressure-matched controls. Cardiac function determination by echodoppler included cardiac filling pressures assessment using tissue Doppler imaging. Blood samples for biological and hormonal determinations were drawn at rest, within 15 min before echocardiography.

RESULTS

As selected, hemodynamic and left and right heart systolic and diastolic functions were located in the normal range in Htx. Plasma ET value was also similar in Htx and controls (20.7 +/- 0.9 vs. 19.6 +/- 0.9 fmol/mL). However, circulating BNP, like cGMP, was still significantly increased after heart transplantation, when compared with controls (33.8 +/- 8.5 vs. 4.0 +/- 0.9 pg/mL, p = 0.002 and 8.2 +/- 1.1 vs. 4.4 +/- 0.3 nmol/L, p = 0.003) for BNP and cGMP, respectively, in Htx and controls. Interestingly, the sole correlation observed was between BNP and cGMP (r = 0.85, p < 0.0001) after heart transplantation.

CONCLUSIONS

After heart transplantation, BNP remained increased despite the normalization of hemodynamic and cardiac systolic and diastolic functions. This suggests that such endocrine heart stimulation should not be viewed only as a hemodynamic marker in Htx. Further studies will be useful to investigate the role of pro-inflammatory cytokines and whether elevated BNP still possesses antifibrotic properties, further supporting the interest of enhancing its activity after heart transplantation.

Sexual dysfunction in patients with cancer

19653

Background: Malignant diseases have a strong influence in quality of life, being sexuality one of the most affected variables. The objetive is to determine the prevalence of sexual dysfunction in a cohort of patients with cancer and its relationship with the following: pain, fatigue, nausea, vomiting, mechanisms of adaptation to stress, anxiety and depression. Methods: Anonymous questionnaires were used, including: treatment, adverse events, Zimong and Snaith depression and anxiety scale, sexual dysfunction questionnaire, coping strategies of Tobin David, Hopwood body image scale and the analogical visual test for pain evaluation. Results: Between January and August 2006, sixty four patients were evaluated; 72% were women; median age: 50 years old. Libido was absent in 50%; this was associated with gender (better in men; p=0,05) and the presence of pain (p=0,05) and fatigue (p=0,05) but not with age. All patients who had intact libido also had arousal and orgasms; this was more prevalent in men than in women and in subjects younger than 60 years. Arousal was absent in 47% of cases. Forty four percent of men had erectile dysfunction; this was present in all patients older than 60 years. Frequency of intercourses was decreased in 75%. Fifty eight percent of patients said that their sexuality was better before the diagnosis of their disease. Interestingly, 85% didn’t talk to their doctors about their sexual problems. Conclusions: One out of 2 patients had sexual dysfunction, predominantly women. Sexuality was affected mainly by pain and fatigue. Although normal libido was present in all ages, subjects older than 60 years had less arousal and orgasms.

No significant financial relationships to disclose.

Photophysics of an electrophosphorescent platinum (II) porphyrin in solid films

We examine electronic processes in platinum (II) octaethyl porphyrin (PtOEP) embedded in an organic solid state matrix and in the form of vacuum-evaporated neat films in conjunction with potential applications of this compound to organic photovoltaic and electrophosphorescent devices. Absorption, photoexcitation, and luminescence spectra indicate the excitonic dimers to be dominant excited states, and their dissociation underlies the charge photogeneration process. Different charge separation distance (1.5 nm and 2.6 nm) in opposite charge carrier pairs preceding dissociation can be distinguished based on the fit of the three-dimensional Onsager theory of geminate recombination to electromodulated luminescence and photoconduction measurements. The near-positive electrode concentrated triplet dimer excitons, produced by strongly 370 nm absorbed light in neat PtOEP films, are efficiently quenched by electron transfer to the metal (Al), generating the positive charge with an efficiency eta+ exceeding 0.15 at high electric fields and dominating the measured photocurrent. Their dissociation efficiency in the bulk, eta- (negatively biased illuminated electrode), is more than one order of magnitude lower than eta+. The dissociation of singlet dimer states dominates the bulk photogeneration process induced by the weakly-absorbed light at 450 nm, with comparable eta+ and eta-. The "hot excited state" underlying the temperature-increasing emission at 540 nm has been attributed to the upper excitonic component Q+ of the first absorption band Q consistent with the exciton concept applied successfully to the interpretation of all dimer-underlain spectroscopic features of PtOEP samples studied.

Fenoldopam mesylate and renal function in patients undergoing liver transplantation: a randomized, controlled pilot trial

To test the relative effects on serum creatinine (CRE), blood urea nitrogen (BUN), and urine output of small-dose dopamine and fenoldopam in patients undergoing liver transplantation, we randomized 43 patients to 1 of 2 continuous infusions over 48 h, starting with anesthesia induction: fenoldopam, 0.1 microg . kg(-1) . min(-1) or dopamine, 2 microg . kg(-1) . min(-1). We used predetermined hemodynamic and intravascular volume goals (intrathoracic blood volume index 800-1000 mL/m(2), extravascular lung water index <7 mL/kg) to manage patients with an algorithm for use of mannitol and furosemide to maintain urine output >1 mL . kg(-1) . h(-1). At postoperative day 3, the median CRE increase was 0.2 mg/dL (interquartile range [IQR] -0.2-0.5) with fenoldopam and 0.5 mg/dL (IQR 0.3-0.9, P = 0.004) in the dopamine group. The BUN increase was median 2 mg/dL (IQR -2-8) versus 8.5 mg/dL (IQR 5-12, P = 0.01), respectively, with fenoldopam versus dopamine. Urine output was similar; however, significantly fewer fenoldopam patients required furosemide compared with dopamine patients (median 1 [IQR 0-3] versus 3 [IQR 2-4], respectively, P = 0.003). The hemodynamic effects of dopamine and fenoldopam were similar. Compared with dopamine, in the setting of liver transplantation, fenoldopam is associated with better CRE and BUN values.

Pool film boiling experiments on a wire in low gravity: preliminary results

This paper reports preliminary results for pool film boiling on a wire immersed in almost saturated FC72 recently obtained during an experimental campaign performed in low gravity on the European Space Agency Zero-G airplane, (reduced gravity level 10(-2)). This is part of a long-term research program on the effect of gravitational and electric forces on boiling. The reported data set refers to experiments performed under the following conditions: (1) Earth gravity without electric field, (2) Earth gravity with electric field, (3) low gravity without electric field, and (4) low gravity with electric field. Although a decrease of gravity causes a heat transfer degradation, the electric field markedly improves heat exchange. This improvement is so effective that, beyond a certain field value, the heat flux is no longer sensitive to gravity. Two main film boiling regimes have been identified, both in normal and in low gravity: one is affected by the electric field and the other is practically insensitive to the field influence.

Post-thoracotomy analgesia: epidural vs intravenous morphine continuous infusion

BACKGROUND

We compared thoracic morphine epidural analgesia (TEA) and I.V. analgesia (IVA) with morphine, in respect to the time to extubation, the quality of postoperative analgesia, side effects, complications, postoperative hospital length of stay in patients having thoracotomy lung resection.

METHODS

We prospectively studied 563 consecutive patients, undergoing thoracotomy (lobectomy, bilobectomy or pneumonectomy), randomized in two groups: TEA 286 patients and IVA 277 patients. In the epidural group, before the induction of anesthesia, continuous infusion of 15 mg of morphine in 250 mL of normal saline at 5 mL/h was started. In the IVA group a continuous infusion of 30 mg of morphine associated with 180 mg ketorolac in 250 mL of normal saline at 5 mL/h was started before the induction of anesthesia. The pain degree was evaluated on an analogic scale by Keele modified at 1 (end of anesthesia) 6, 12, 24, and 48 postoperative hours, at rest and after movements. Data obtained were analysed by means of the analysis of variance for repeated measures.

RESULTS

The time from the end of surgery to tracheal extubation was similar in both groups. Significantly lower numeric verbal pain scores at rest and after movements were found in the epidural group (p<0.001). Postop complications, nausea and vomiting were higher in the IVA group (p<0.05). Postoperative mean hospital length of stay was 9+/-4 days in TEA and 11+/-4 in the IVA group (p<0.05).

CONCLUSIONS

In our study the epidural root was superior in terms of analgesia, side effects, length of stay and postoperative complications after thoracotomy.

Role of pre-emptive analgesia in reduction mammaplasty

Pre-emptive analgesia is an antinociceptive treatment that prevents altered central excitability from high intensity noxious stimuli. The aim of this study was to evaluate the efficacy of pre-emptive analgesia in patients due to have elective breast reduction that usually requires drugs for postoperative pain control. Sixty women, ASA grades I-II, were randomly divided into two groups: 30 patients were given ropivacaine infiltration 1.5 mg/ml plus adrenaline 1/200,000 in normal saline 100 ml before the skin incision, and 30 had normal saline 100 ml plus adrenaline 1/200,000 infiltrated. Postoperative pain was evaluated by an observer who was unaware of the treatment given, and scored on a visual analogue score (VAS) during the first 72 hours postoperatively. Analgesic requirements were recorded. There was a statistically significant difference between groups in the amount of additional pain control required during the early postoperative period, which suggests that pre-emptive analgesia reduces pain after reduction mammaplasty.

[Anesthesia for lung volume reduction surgery]

BACKGROUND

Lung volume reduction surgery (LVRS) has become a novel palliative procedure for a subgroup of patients with advanced non-bullous emphysema.

METHODS

Seventy-six patients with severe emphysema were evaluated: ten patients were considered for lung transplantation and only 24 underwent LVRS. In all patients an epidural catheter was inserted between the T5-T9 space. During one lung ventilation (OLV), ventilatory setting was adjusted to avoid air trapping and/or dynamic hyperinflation and high frequency jet ventilation was used when PaO2/ FiO2 was lower than 60 mmHg in 5 patients. Permissive hypercapnia (PaCO2=53 mmHg) was allowed to avoid hyperinflation and reach hemodynamic stability.

RESULTS

During OLV PaO2/FiO2 was 148+/-80 mmHg, PaCO2 53+/-11 mmHg, mPA 27+/-2 mmHg and Qsp/Qt was 38+/-6%. Although the high risk patients, there were no complications due to hypercapnia during surgery. Twenty-three patients were extubated successfully at the end of the surgery (PaO2/FiO2 179+/-34 mmHg and PaCO2 59+/-11 mmHg) and only one patient was not extubated because of air leakage and died for postoperative respiratory failure after 20 days. Another patient died because of sepsis after 15 days. Numeric Ordinal Verbal Scale (by Keele modified) was used for postoperative pain degree at 0, 12th and 24th hours. No patients had pain>2.

CONCLUSIONS

In conclusion, a careful anesthesia technique with an accurate intraop monitoring associated with thoracic epidural analgesia even in Video Assisted Thoracic Surgery is suggested in LVRS patients; 12 months postoperative data confirm the validity of the procedure (FEV1 24 AE 36%, FVC 53 AE 70%, RV 265 AE 199% and 6MWT 213 AE 330 m).

Inhaled nitric oxide administration during one-lung ventilation in patients undergoing thoracic surgery

OBJECTIVE

To evaluate the effects of inhaled nitric oxide (iNO) on hemodynamics and oxygenation during one-lung ventilation (OLV) in the lateral decubitus position in patients undergoing elective thoracic surgery.

DESIGN

Prospective study.

SETTING

University hospital.

PARTICIPANTS

Thirty consecutive patients scheduled for thoracotomy.

INTERVENTIONS

Anesthesia consisted of thoracic epidural analgesia combined with general anesthesia (isoflurane, fentanyl, and vecuronium bromide). Systemic and pulmonary circulations were monitored with a radial artery catheter and a pulmonary artery catheter. Inhaled NO, 40 ppm, was administered during OLV, and the inhaled gas mixture was monitored for NO and nitrogen dioxide (NO2). Hemodynamic and oxygenation data were collected before and during inhaled NO administration.

MEASUREMENTS AND MAIN RESULTS

Inhaled NO caused a reduction of pulmonary vascular resistance index from 249 +/- 97.6 dyne. sec. cm(-5) to 199.3 +/- 68.9 dyne. sec. cm(-5) (p < 0.05), without effects on systemic hemodynamics or impairment of oxygenation. A stratification of the patients according to values of QS/QT (< 30%, 30% to 44%, > or = 45%), PaO(2)/fraction of inspired oxygen (> or = 200, 100 to 199, < 100), and pulmonary hypertension (mean pulmonary arterial pressure < 24 or > or = 24 mmHg) showed that inhaled NO causes a significant reduction of mean pulmonary artery pressure in patients with pulmonary hypertension, mainly as a result of a reduction of pulmonary vascular resistance index, and improves oxygenation by reducing intrapulmonary shunt in patients with severe hypoxemia during OLV.

CONCLUSIONS

Inhaled NO administration neither significantly decreased mean pulmonary arterial pressure in patients with normal pulmonary artery pressure nor improved oxygenation in nonhypoxic patients. Nevertheless, inhaled NO is effective in patients with pulmonary hypertension and hypoxemia during OLV.

Pediatric renal transplantation: anesthesia and perioperative complications

The appropriate choice of anesthesia for patients (pts) undergoing renal transplantation (Ktx) requires minimal toxicity and accurate monitoring for pts at high risk for metabolic, cardiovascular, and respiratory perioperative complications. We evaluated the anesthetic management and postoperative follow-up in pediatric Ktx performed in the last 12 years in our institution. From 1988 to 1999, 75 ASA class II-III pts (45 males, 22 females) younger than 18 years scheduled for Ktx were studied: 49 received a graft from a cadaveric donor (CD) and 26 from a living donor (LD). All pts were treated with dialysis within 24 h before the procedure. Standard monitoring consisted of an electrocardiogram, central venous pressure, non-invasive arterial pressure, pulse oximetry, and inspiratory and expiratory gas analysis. If necessary, an arterial cannula and pediatric pulmonary catheter were introduced. Anesthesia was induced with sodium thiopental, propofol, halothane, or sevoflurane and maintained with isoflurane and/or fentanyl and droperidol in O2:N2O (FiO2 0.4%). As muscle relaxants atracurium or cisatracurium besilate were used, except in allergic pts, in whom vecuronium or rocuronium bromide was administered. Dopamine, 20% mannitol, and furosemide were used to increase diuresis. Continuous morphine and ketoralac infusions were used for postoperative pain relief. The surgical technique was the same in all cases. Complications and renal-function (RF) recovery were evaluated relating to CD and LD using the chi-square test; differences in mean anesthesia and surgical time were evaluated by Student's t-test; survival curves were calculated from the day of Ktx to death or last follow-up and estimated by the Kaplan-Meier method. Values of P below 0.05 were considered significant. Postoperative immunosuppressive therapy was based on cyclosporine together with other conventional drugs. Mean anesthesia time was 228 +/- 65 min. Mean kidney ischemia time for CD was 16.5 +/- 4 h. Four pts (3 CD, 1 LD) died within 72 h postoperatively: 3 due to cardiac failure and 1 to metabolic coma. Six pts showed cardiovascular and 3 had infective complications, all successfully treated. Three pts (2 CD, 1 LD) died within 2 to 12 months after, surgery; 10 (6 CD, 4 LD) had graft failure and are still alive on dialysis; 58 (38 CD, 20 LD) are alive in good health after a mean follow-up of 57.6 +/- 36.6 months (range 12-120 months). Fifteen of 26 pts younger than 12 years (21 CD and 5 LD) recovered RF intraoperatively (10 CD, 5 LD); 1 with CD and 1 with LD showed postoperative graft failure and 2 with CD died within 72 h postoperatively, 22 (18 CD and 4 LD) are alive in good health. This group showed no statistical difference compared to pts older than 12 years. Of 16 pts (15 CD and 1 LD) with body weight (BW) less than 25 kg, 6 showed intraoperative (5 CD, 1 LD) recovery of RF. The 3 deaths were all in CD pts, 2 within 72 h and one 2 months after surgery; only 1 LD had postoperative graft failure. Twelve pts (75%) (12 CD, 80%) are alive in good health. Compared to pts with BW of 25 kg or more, this group showed lower intraoperative recovery of RF (P < or = 0.05). No peri- and postoperative complications occurred in all 26 LD pts (100%). Recent advances in surgery, anesthesia, immunosuppression, and antimicrobial prophylaxis have made Ktx a more predictable procedure even in pediatric pts. For high-risk pts, mortality and morbidity can be controlled by accurate surgical, anesthetic, and postoperative management. Pts younger than 12 years and with BW less than 25 kg are more likely to develop peri- and postoperative complications.

Further study on the specificity and incidence of neutralizing antibodies to interferon (IFN) in relapsing remitting multiple sclerosis patients treated with IFN beta-1a or IFN beta-1b

The development of neutralizing antibodies (NAbs) to interferon (IFN) is a common phenomenon of IFN beta therapy for relapsing-remitting multiple sclerosis (RRMS) patients. Here we examine the specificity of NAbs developed during therapy for RRMS with recombinant interferon (rIFN) beta-1a or rIFN beta-1b, and study the effect of switching from rIFN beta-1a to rIFN beta-1b on the incidence and specificity of NAbs. The relative ability to neutralize rIFN beta-1a and beta-1b was assayed in sera positive for NAbs derived from RRMS patients treated with either rIFN beta-1a (N=9) or rIFN beta-1b (N=16), while the incidence and specificity of NAbs to IFN beta developed during therapy were studied in 50 RRMS patients who were treated for two years with rIFN beta-1a followed by a further year either switching to rIFN beta-1b (N=34) or continuing treatment with rIFN beta-1a (N=16). The results show that all positive sera, independent of the source, may recognize both forms of rIFN beta and that a further year of treatment does not significantly affect the incidence and specificity of the NAbs developed during the first two years of treatment even if treatment is switched to a different type of IFN beta. The data then suggests that it is unlikely that the administration of rIFN beta-1b to anti-rIFN beta-1a NAbs-positive patients can overcome the inhibitory effect exerted by the serum antibodies (and vice versa), and that a further period of treatment with IFN beta-1b in patients previously treated with rIFN beta-1a does not significantly change the pattern of antibody response to IFN beta.

Calcium chloride minimizes the hemodynamic effects of propofol in patients undergoing coronary artery bypass grafting

OBJECTIVE

To assess the hemodynamic effects of propofol and the counteracting effect of calcium chloride (CaCl2) in patients undergoing coronary artery bypass grafting (CABG).

DESIGN

Prospective, randomized study.

SETTING

University hospital, department of cardiac surgery.

PARTICIPANTS

Fifty-eight patients undergoing elective CABG, divided into group A (n = 29) and group B (n = 29).

INTERVENTIONS

Anesthesia was induced with a combination of fentanyl, 7 microg/kg; pancuronium, 0.1 mg/kg; and propofol, 1.5 mg/kg, administered over 60 seconds. A blinded investigator administered saline in group A patients and 10 mg/kg of CaCl2 in group B patients at the same speed and same time as propofol administration through another lumen of the central venous catheter.

MEASUREMENTS AND MAIN RESULTS

Hemodynamic data were obtained at baseline (T0), 2 minutes after anesthesia induction (T1), and 2 minutes after tracheal intubation (T2). Heart rate decreased significantly in group A patients (86.2+/-11.3 beats/min at T0 and 72.8+/-7.5 beats/min at T2; p < 0.001). Mean arterial pressure decreased significantly in patients in both groups (group A, 108.0+/-12.0 mmHg at T0; 74.6+/-14.6mmHg at T2;p < 0.001 and group B, 106.0+/-10.2 mmHg at T0; 90.4+/-10.0 mmHg at T2; p < 0.05). Stroke volume index, cardiac index, and cardiac output decreased in group A patients (39.4+/-4.1 mL/beat/m2 at T0 and 28.8+/-5.2 mL/beat/m2 at T2; p < 0.05; 3.4+/-0.6 L/min/m2 at T0 and 1.9+/-0.3 L/min/m2 at T2; p < 0.001; 5.9+/-0.9 L/min at T0 and 3.4+/-0.4 L/min at T2; p < 0.001, respectively), whereas in group B patients, changes were negligible (38.1+/-7.0 mL/beat/m2 at T0 v 35.7+/-6.6 mL/beat/m2 at T2; (NS) 3.3+/-0.5 L/min/m2 at T0 v 2.7+/-0.3 L/min/m2 at T2; (NS) 5.7+/-0.9 L/min at T0 v 4.7+/-0.5 L/min at T2; (NS), respectively).

CONCLUSION

Simultaneous administration of CaCl2 during the induction of anesthesia minimizes the potential negative effect of propofol on cardiac function in cardiac patients.