Melatonin reduces the need for sedation in ICU patients: a randomized controlled trial

BACKGROUND

Critically ill patients suffer from physiological sleep deprivation and have reduced blood melatonin levels. This study was designed to determine whether nocturnal melatonin supplementation would reduce the need for sedation in patients with critical illness.

METHODS

A single-center, double-blind randomized placebo-controlled trial was carried out from July 2007 to December 2009, in a mixed medical-surgical Intensive Care Unit of a University hospital, without any form of external funding. Of 1158 patients admitted to ICU and treated with conscious enteral sedation, 82 critically-ill with mechanical ventilation >48 hours and Simplified Acute Physiology Score II>32 points were randomized 1:1 to receive, at eight p.m. and midnight, melatonin (3+3mg) or placebo, from the third ICU day until ICU discharge. Primary outcome was total amount of enteral hydroxyzine administered.

RESULTS

Melatonin treated patients received lower amount of enteral hydroxyzine. Other neurological indicators (amount of some neuroactive drugs, pain, agitation, anxiety, sleep observed by nurses, need for restraints, need for extra sedation, nurse evaluation of sedation adequacy) seemed improved, with reduced cost for neuroactive drugs. Post-traumatic stress disorder prevalence did not differ between groups, nor did ICU or hospital mortality. Study limitations include the differences between groups before intervention, the small sample size, and the single-center observation.

CONCLUSION

Long-term enteral melatonin supplementation may result in a decreased need for sedation, with improved neurological indicators and cost reduction. Further multicenter evaluations are required to confirm these results with different sedation protocols.

Aerophagia increases the risk of ventilator-associated pneumonia in critically-ill patients

BACKGROUND

Gastric residual volume in ventilated critically ill may complicate gut function. Over the years studies suggested to tolerate progressively higher residuals. The relationship between such volumes and the development of ventilator-associated pneumonia (VAP) is still under debate. No reports deal with the relevant anecdotal finding of air in the stomach. Aim of the present study is to test the role of air in the development of VAPs.

METHODS

Prospective observational trial in consecutive patients with a predicted length of ICU stay >3 days. The first 8 days of stay were studied. Sedation was targeted to have awake/cooperative patients. Early enteral nutrition was attempted. Gastric content was measured every 4 hours by 60 mL-syringe suction. Upper digestive intolerance (UDI) was defined as >2 consecutive findings of liquid >200 mL, aerophagia was defined as >2 consecutive findings of air >150 mL.

RESULTS

Three hundred sixty-four patients enrolled, 43 developed VAP (11.8%). Patients were sedated with enteral (76% total time), intravenous (6%) or both (28%) drugs. Conscious sedation was achieved in 54% of the observations. 326 patients began enteral nutrition during the first 24 hours (1000 kcal median calorie intake). 10% developed UDI, 15% had aerophagia. No association was found between VAP and UDI (P=0.78), while significant association was found between VAP and aerophagia (OR=2.88, P<0.01). A sensitivity analysis, excluding patients admitted with respiratory infection, confirmed the results.

CONCLUSION

High volumes of air in the stomach significantly increased the risk of developing VAP, while gastric residual volumes were not associated with the incidence of pneumonia.

Performance assessment of a glucose control protocol in septic patients with an automated intermittent plasma glucose monitoring device

BACKGROUND & AIMS

The optimal level and modality of glucose control in critically ill patients is still debated. A protocolized approach and the use of nearly-continuous technologies are recommended to manage hyperglycemia, hypoglycemia and glycemic variability. We recently proposed a pato-physiology-based glucose control protocol which takes into account patient glucose/carbohydrate intake and insulin resistance. Aim of the present investigation was to assess the performance of our protocol with an automated intermittent plasma glucose monitoring device (OptiScanner™ 5000).

METHODS

OptiScanner™ was used in 6 septic patients, providing glucose measurement every 15' from a side-port of an indwelling central venous catheter. Target level of glucose was 80-150 mg/dL. Insulin infusion and kcal with nutritional support were also recorded.

RESULTS

6 septic patients were studied for 319 h (1277 measurements); 58 [45-65] hours for each patient (measurements/patient: 231 [172-265]). Blood glucose was at target for 93 [90-98]% of study time. Mean plasma glucose was 126 ± 11 mg/dL. Only 3 hypoglycemic episodes (78, 78, 69 mg/dL) were recorded. Glucose variability was limited: plasma glucose coefficient of variation was 11.7 ± 4.0% and plasma glucose standard deviation was 14.3 ± 5.5 mg/dL.

CONCLUSIONS

The local glucose control protocol achieved satisfactory glucose control in septic patients along with a high degree of safeness. Automated intermittent plasma glucose monitoring seemed useful to assess the performance of the protocol.

Intensive care of patients requiring open abdomen treatment: a case-series analysis

BACKGROUND

This retrospective overview examines the management of patients with temporary open abdomen (OA).

METHODS

The clinical characteristics and intensive care treatment of 34 consecutive patients with OA (1996-2012) were reviewed.

RESULTS

Average age was 61 years, SAPS II score 43, SOFA 8. Two patients had non-contaminated abdomen; 12 had intact gut (only 8 later during stay); 7 repaired gut (only later 4); 13 cutaneous stoma (later 14), and 2 entero-atmospheric fistula (later 8+1 entero-enteral). The median ICU stay was 48 [36-94] days. One quarter of the 2376 ICU-days were classified as severe sepsis/septic shock (antibiotics were given for two thirds of the stay); three quarters were with ventilation; in 95% of days sedatives were given (mainly enterally). Continuous cavity lavage was done in three quarters of days; in 3% of days patients were fasted whereas >20 kcal/kg was given for 74% of days; we fed the gut in 95% of fed-days, in half of them combined with parenteral nutrition. Complications are discussed; mortality was 32.4%, limited to the ICU stay.

CONCLUSION

The intensive care of patients with OA is challenging but can achieve better outcomes than expected. Continuous abdominal lavage improves the evacuation of contaminated fluid or debris and, coupled with antiseptics and low antibiotic pressure, reinforces the control of infection. The gut can be used for nutrition (even without gastrointestinal continuity), and long-term light sedation (mainly enteral) with minimal impact on perfusion, ventilation and gut motility.

Time course of endogenous nitric oxide inhibitors in severe sepsis in humans

AIM

Asymmetric and symmetric dimethylarginines (ADMA and SDMA, respectively) are protein breakdown markers; both compete with arginine for cellular transport and both are excreted in urine. Moreover, ADMA is a non-selective inhibitor of nitric oxide (NO) synthase that is metabolized by a specific hydrolase in which the activity during stress remains controversial. While an increase in ADMA is known to be associated with adverse events, little is known about SDMA. We investigated plasma ADMA and SDMA levels during ICU stay to reveal the time course of endogenous NO inhibition in patients with sepsis.

METHODS

A post hoc analysis from a prospective random controlled trial conducted in three ICUs was performed to study the pathophysiological pathways of sepsis. ADMA, SDMA, the ratio of ADMA/SDMA (a marker of ADMA catabolism), arginine, interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-alpha), and C reactive protein (CRP) were measured on days 1, 3, 6, 9, 12 and at discharge in 72 consecutive severely septic patients.

RESULTS

Fasting basal glycemia, creatinine, IL-6, TNF-alpha, CRP, ADMA, and SDMA were higher than normal. The ADMA/SDMA ratio was decreased by 50%, and arginine levels were low. ADMA levels were related to the total Sequential Organ Failure Assessment (SOFA) scores and arginine levels, and inversely related to IL-6 and CRP levels. SDMA levels were related to Simplified Acute Physiologic Scores II (SAPS II), SOFA scores, blood urea, creatinine, and arginine levels. The ADMA/SDMA ratio was inversely related to IL-6 levels. In 58 ICU survivors, creatinine, IL-6, and CRP levels decreased over time; ADMA levels increased, SDMA levels remained stable, and the ADMA/SDMA ratio increased. In 14 non-survivors, creatinine, IL-6, TNF-alpha, CRP, and ADMA levels were stable, whereas the SDMA levels increased and the ADMA/SDMA ratio remained low. In both ICU survivors and non-survivors, the levels on the last ICU day confirmed the data trends. SDMA, but not ADMA, was associated with ICU mortality.

CONCLUSION

ADMA catabolism appears to be activated by inflammation; its increase during the advanced septic phase in surviving patients may suggest an endogenous inhibition of NO synthesis during the full-blown septic phase. In severe sepsis, SDMA, but not ADMA, appears to be a marker of alterations in vital functions and mortality.

Effects of recombinant human activated protein C on the fibrinolytic system of patients undergoing conventional or tight glycemic control

AIM

Recombinant human activated protein C (rh-APC) and tight glycemic control (TGC) have been shown to reduce mortality in septic patients. Both interventions can reduce the plasma concentration and/or activity of the most powerful suppressor of fibrinolysis, plasminogen activator inhibitor-1 (PAI-1). Our aim was to evaluate the effects on the fibrinolytic system after the administration of rh-APC in septic patients undergoing conventional or TGC.

METHODS

Posthoc analysis of data was collected from 90 patients with severe sepsis/septic shock, randomized to either conventional or TGC groups. Independent of these treatments, patients with at least two organ dysfunctions simultaneously received rh-APC. Plasma levels of multiple biochemical markers for fibrinolysis, coagulation, and inflammation were determined every day for the 1st week and then on study days 9, 11, 13, 18, 23, and 28. Clinical data and sepsis-related organ failure assessment (SOFA) scores were also recorded.

RESULTS

Patients who had received rh-APC exhibited significantly more impairments in fibrinolysis at baseline (PAI-1 activity 49.76 [24.61-71.82] vs 21.92 [6.47-55-83] IU/mL, P=0.03). The reductions in plasma PAI-1 activity over time associated with rh-APC treatment were different according to whether the treatment was administered to patients undergoing conventional or TGC (P=0.01). However, the most prominent reductions were in patients undergoing conventional glycemic control. Significant interactions between the two study interventions were also found for PAI-1 concentration (P<0.001), C-reactive protein (P=0.02), and interleukin-6 levels (P<0.001).

CONCLUSIONS

Both rh-APC and TGC appear to improve fibrinolysis in septic patients. The reduction in the impairment of fibrinolysis associated with rh-APC treatment seems greater in patients undergoing conventional glycemic control than in those undergoing TGC.

Reclamation and agricultural reuse of wastewater: the experience of the Cagliari sewage treatment plant (Sardinia, Italy)

In Sardinia, as in many other Mediterranean regions, recurrent droughts and climate change have dramatically reduced available water resources. As a result of this critical situation, in 1995 the Italian Government declared a state of emergency and drew up a program for financial support by the State and local authorities with the aim of reducing this serious deficit. One of the actions focused on reclaiming and reusing the effluent from the sewage treatment plant of Cagliari. This article reports on the multidisciplinary preliminary study performed by the Ente Acque della Sardegna (ENAS) to evaluate the suitability of reusing Is Arenas effluent for irrigation and on the operation of the tertiary treatment plant.

Metabolic treatment of critically ill patients: energy balance and substrate disposal

Oxidation of substrates is the main biochemical process used by the human body to produce energy. Different substrates (carbohydrates, lipids, and proteins) have different effects on oxygen consumption and carbon dioxide production: during the critical phase of pathologies it could be relevant pay attention to the use of various nutrients, that have some altered effect respect to the normal subjects metabolism, and during the length of metabolic treatment, too. Generally, nutrition lead to replenish body stores, while endogenous substrates are used to be oxidized. Critically ill patients show a preference for prompt energy availability (i.e. glucose) to avoid endogenous protein catabolism; lipids are shown to have a more pronounced storage effect. Adequate amount of energy intake in carbohydrates determine an increase of RQ, that means a shift from a more lipid-based to a more glucose-based oxidation. Composition of dietary intake can be usefully different for each pathology, and also for different periods of the same pathology, because critically ill patients have a variety of metabolic needs during their stay in ICU.

Different types of hysterectomy in the radio-surgical treatment of early cervical cancer (FIGO Ib-IIa)

PURPOSE OF INVESTIGATION

Surgery and radiotherapy achieved equivalent results for FIGO stages Ib-IIa invasive cervical carcinoma. The integration of radiotherapy and surgery provided the same results for a selected series of patients without increasing the rate of complications. The aim of the study was to verify if, applying a radio-surgical protocol, the reduction of the surgery extension on the parametrium in one of two consecutive series might achieve the same results in terms of survival and recurrence rates with fewer complications.

MATERIAL AND METHODS

We analysed actuarial survival (with >10-year follow-up), local control rates and morbidity of 390 patients who had different the kinds of surgery applied in the radio-surgical treatment protocol: Protocol A: brachytherapy plus type III radical hysterectomy vs Protocol B: brachytherapy plus type II radical hysterectomy. Patients were all included in an analysis of complications according to the French-Italian glossary.

RESULTS

Analyses showed no differences in terms of survival, patterns of recurrences and onset time within the two protocols. Urinary complications were more frequent and severe in protocol A vs protocol B (G2: 26.5% vs. 6.1%; G3: 5.3% vs. 3.6%).

CONCLUSION

Our study pointed out that the reduction of the surgery extension allowed the same overall survival and relapses with fewer complications particularly in terms of grade of severity.

Stable transformation of erysiphe graminis an obligate biotrophic pathogen of barley

Barley powdery mildew, Erysiphe graminis f.sp. hordei, is an obligate biotrophic pathogen and as such cannot complete its life cycle without a living host. The inability to transform this fungus and manipulate its genome has constrained research towards understanding its life cycle and pathogenicity. Here we describe an in planta transformation system based on delivery of DNA using a gold-particle gun and selection using benomyl or bialaphos. Using this method, we consistently obtained stable transformants with efficiencies comparable to other filamentous fungi. Stable expression of the beta-glucuronidase in E. graminis was demonstrated by co-transforming the uidA gene with the selectable markers.

[Ciaglia's percutaneous dilatative tracheostomy in intensive care. Perioperative complications and long-term results]

BACKGROUND AND AIM

The introduction of percutaneous tracheostomic techniques using dilatation (PDT) has led to the gradual disuse of conventional methods of surgery. The aim of this study was to evaluate ventilatory function in critical patients during the execution of PDT using Ciaglia's method as well as, in the postoperative phase, the long-term results, namely endotracheal lesions and cosmetic deformities of the stoma.

EXPERIMENTAL DESIGN

A prospective study was carried out on a consecutive series of adult patients.

SETTING

The intensive care ward of a 600-bed teaching hospital.

PATIENTS

A group of 50 critical patients undergoing PDT from 1993 to 1996. Valuations of ventilatory function: expiratory volume (EV), PaO2 and PaCO2, were calculated in 40 patients undergoing PDT. Endoscopic controls of the trachea were performed in 21 surviving patients 60 days after the removal of the tracheostomic tube and a cosmetic evaluation of the tube insertion site was also made in the same patients.

RESULTS

During PDT a mean reduction of EV was observed of 1.41/min and PaO2 values also diminished 15% accompanied by a 14.2% increase in PaCO2. The endoscopic control performed after 60 days in 21 out of 50 patients revealed a subglottal stenosis in 1 patient, the presence of nonstenosing cicatricial granuloma in 2 patients, edema in 2 patients and dysepithelisation of the tracheal mucosa in a further 2 patients. The remaining 66% showed flattening of the mucosa and complete restitutium ad integrum. No usurpations and cicatricial tractions of the tube insertion site were observed.

CONCLUSIONS

This prospective study of intraoperative ventilatory function and the final outcome of PDT according to Ciaglia confirms that this is a reliable technique for the ventilatory management of critical patients with a low percentage of long-term complications.

Use of monoclonal antibodies to determine biomass of Cladosporium fulvum in infected tomato leaves

A monoclonal antibody, OX-CH1, was raised against surface washings of Cladosporium herbarum. This antibody recognizes an epitope that is found in various fungi belonging to the genus Cladosporium, including C. fulvum, the causal agent of tomato leaf mold. The epitope is present at comparable levels in two different races of C. fulvum and in transgenic isolates derived from them. The epitope is heat-and protease-resistant but sensitive to oxidation with periodate and it is constitutively expressed in C. fulvum grown in pure culture and on the plant. C. fulvum can be detected in infected tissues at levels starting from around 1 mg fresh weight of fungus per g fresh weight of leaf tissue. Noninfected tomato leaves do not cross-react with OX-CH1. We have developed an enzyme-linked immunosorbent assay (ELISA) for fungal biomass in tomato leaves and compared it with the assay based on measurements of beta-glucuronidase (GUS) activity in tissues infected with a transgenic isolate of C. fulvum race 4 carrying a uidA gene; the two assays give similar results.

HCF-1, a hydrophobin from the tomato pathogen Cladosporium fulvum

A hydrophobin, named HCF-1, was isolated from the culture medium of Cladosporium fulvum, the causal agent of tomato leaf mould. The protein forms insoluble aggregates when the medium is vigorously aerated. These aggregates can be dissociated by trifluoroacetic acid into monomers which migrate as 10-kDa molecules on SDS-PAGE. HCf-1 is encoded by a single gene, HCf-1. The gene contains two small introns and is translated into a 105-amino acid protein which is then processed to give a mature 83-amino acid protein. The position of the eight cysteine residues and the predicted hydrophobicity profile are typical of fungal hydrophobins. HCf-1 RNA is expressed in growing mycelium and conidia but its quantity diminishes transiently after germination; its abundance does not change when the fungus is grown on nitrogen- or carbon-deficient medium. This is the first step in evaluating the role of hydrophobins in establishment of basic compatibility between C. fulvum and tomato.

The Apparent Turnover of 1-Aminocyclopropane-1-Carboxylate Synthase in Tomato Cells Is Regulated by Protein Phosphorylation and Dephosphorylation

In suspension-cultured cells of tomato (Lycopersicon esculentum Mill.), the activity of 1-aminocyclopropane-1-carboxylate synthase (ACC-S) rapidly increases in response to fungal elicitors. The effect of inhibitors of protein kinases and protein phosphatases on the regulation of ACC-S was studied. K-252a, an inhibitor of protein kinases, prevented induction of the enzyme by elicitors and promoted its apparent turnover in elicitor-stimulated cells, causing a 50% loss of activity within 4 to 8 min in both the presence and absence of cycloheximide. Calyculin A, an inhibitor of protein phosphatases, caused a rapid increase of ACC-S in the absence of elicitors and an immediate acceleration of the rate of ACC-S increase in elicitor-stimulated cells. In the presence of cycloheximide there was no such increase, indicating that the effect depended on protein synthesis. Cordycepin, an inhibitor of mRNA synthesis, did not prevent the elicitor-induced increase in ACC-S activity but strongly reduced the K-252a-induced decay and the calyculin A-induced increase of its activity. In vitro, ACC-S activity was not affected by K-252a and calyculin A or by treatments with protein phosphatases. These results suggest that protein phosphorylation/dephosphorylation is involved in the regulation of ACC-S, not by regulating the catalytic activity itself but by controlling the rate of turnover of the enzyme.

The protein phosphatase inhibitor calyculin A mimics elicitor action in plant cells and induces rapid hyperphosphorylation of specific proteins as revealed by pulse labeling with [33P]phosphate

Suspension-cultured tomato cells react to microbial signals, so-called elicitors, with rapid alkalinization of the growth medium and increased biosynthesis of the stress hormone ethylene. These responses to elicitors can be blocked by staurosporine and K-252a, two specific inhibitors of protein kinases. Here we show that calyculin A, a potent inhibitor of protein phosphatases, mimics the action of elicitors and, at nanomolar concentrations, induces medium alkalinization as well as a strong increase in the activity of 1-aminocyclopropane-1-carboxylate synthase, the key enzyme of ethylene biosynthesis. Both responses were strongly inhibited by K-252a, and calyculin A induced both responses more rapidly than did a fungal elicitor, xylanase. For example, the lag phase for medium alkalinization was only 0.2-0.4 min for calyculin A, compared with 2 min for xylanase. To study changes in the dynamics of protein phosphorylation, cells were labeled with 30-sec pulses of [33P]orthophosphate. Calyculin A strongly increased phosphorylation of several polypeptide bands within 40 sec of treatment. The same phosphorylated bands also appeared in response to xylanase, but only after a lag phase of 2-3 min. These results show that the protein phosphatase inhibitor calyculin A leads to rapid hyperphosphorylation of specific proteins in cultured cells and indicate that elicitor action could be based on inhibition of a protein phosphatase as well as on activation of a protein kinase.

Analysis and cloning of the ethylene-forming enzyme from tomato by functional expression of its mRNA in Xenopus laevis oocytes

The last step in biosynthesis of the plant hormone ethylene, oxidation of 1-aminocyclopropane-1-carboxylic acid (ACC), is catalysed by the elusive ethylene-forming enzyme (EFE). EFE is induced by fungal elicitors in suspension-cultured tomato cells. We demonstrate that Xenopus laevis oocytes injected with RNA from elicitor-treated tomato cells gain the ability to convert ACC to ethylene. The enzyme expressed in the oocytes under the direction of plant RNA is indistinguishable from genuine plant EFE with regard to its saturation kinetics, its iron dependency and its stereospecificity to the diastereomeric ethyl derivatives of ACC, allocoronamic acid and coronamic acid. In tomato cells stimulated for different times with elicitor, the level of EFE correlates with the level of RNA directing EFE expression in oocytes. Hybridization and co-injection experiments demonstrate that the tomato RNA species directing EFE expression in oocytes are homologous to clone pTOM13 which has been shown to inhibit ethylene production in plants when expressed in antisense. Using a cDNA library from elicitor-stimulated tomato cells, we have isolated several homologues of pTOM13 and identified one of them, pHTOM5, as a clone of EFE on the basis of its functional expression in the Xenopus oocytes.

Inactivation of stress induced 1-aminocyclopropane carboxylate synthase in vivo differs from substrate-dependent inactivation in vitro

The activity of 1-aminocyclopropane carboxylate (ACC) synthase increased rapidly in tomato (Lycopersicon esculentum Mill.) leaf discs after vacuum infiltration, reached a maximum after about 30 minutes, and subsequently decayed with an apparent half-life of about 20 minutes. Aminoethoxyvinylglycine, a known inhibitor of ACC synthase, did not alter the apparent turnover of ACC synthase in vivo although it efficiently blocked inactivation of the enzyme by its substrate S-adenosylmethionine in vitro. Similar results were obtained, using a novel assay with permeabilized cells, for ACC synthase in tomato cell cultures treated with a fungal elicitor. The results indicate that inactivation of ACC synthase in vivo differs from substrate-dependent inactivation in vitro.

Chitinase in roots of mycorrhizal Allium porrum: regulation and localization

Chitinase (EC 3.2.1.14) activity was measured in roots of Allium prorrum L. (leek) during development of a vesicular-arbuscular mycorrhizal symbiosis with Glomus versiforme (Karst.) Berch. During the early stages of infection, between 10 and 20 d after inoculation, the specific activity of chitinase was higher in mycorrhizal roots than in the uninfected controls. However, 60-90 d after inoculation, when the symbiosis was fully established, the mycorrhizal roots contained much less chitinase than control roots. Chitinase was purified from A. porrum roots. An antiserum against beanleaf chitinase was found to cross-react specifically with chitinase in the extracts from non-mycorrhizal and mycorrhizal A. porrum roots. This antiserum was used for the immunocytochemical localization of the enzyme with fluorescent and gold-labelled probes. Chitinase was localized in the vacuoles and in the extracellular spaces of non-mycorrhizal and mycorrhizal roots. There was no immunolabelling on the fungal cell walls in the intercellular or the intracellular phases. It is concluded that the chitin in the fungal walls is inaccessible to plant chitinase. This casts doubts on the possible involvement of this hydrolase in the development of the mycorrhizal fungus. However, fungal penetration does appear to cause a typical defense response in the first stages that is later depressed.