USH2A Gene Mutations in Rabbits Lead to Progressive Retinal Degeneration and Hearing Loss

Purpose

Mutations in USH2A gene are responsible for the greatest proportion of the Usher Syndrome (USH) population, among which more than 30% are frameshift mutations on exon 13. A clinically relevant animal model has been absent for USH2A-related vision loss. Here we sought to establish a rabbit model carrying USH2A frameshift mutation on exon 12 (human exon 13 equivalent).

Methods

CRISPR/Cas9 reagents targeting the rabbit USH2A exon 12 were delivered into rabbit embryos to produce an USH2A mutant rabbit line. The USH2A knockout animals were subjected to a series of functional and morphological analyses, including acoustic auditory brainstem responses, electroretinography, optical coherence tomography, fundus photography, fundus autofluorescence, histology, and immunohistochemistry.

Results

The USH2A mutant rabbits exhibit hyper-autofluorescent signals on fundus autofluorescence and hyper-reflective signals on optical coherence tomography images as early as 4 months of age, which indicate retinal pigment epithelium damage. Auditory brainstem response measurement in these rabbits showed moderate to severe hearing loss. Electroretinography signals of both rod and cone function were decreased in the USH2A mutant rabbits starting from 7 months of age and further decreased at 15 to 22 months of age, indicating progressive photoreceptor degeneration, which is confirmed by histopathological examination.

Conclusions

Disruption of USH2A gene in rabbits is sufficient to induce hearing loss and progressive photoreceptor degeneration, mimicking the USH2A clinical disease.

Translational Relevance

To our knowledge, this study presents the first mammalian model of USH2 showing the phenotype of retinitis pigmentosa. This study supports the use of rabbits as a clinically relevant large animal model to understand the pathogenesis and to develop novel therapeutics for Usher syndrome.

The carbon footprint of steel corrosion

The monetary cost of corrosion is currently estimated at 3 to 4% of the global GDP considering direct costs exclusively. However, no study to date has quantified the environmental impact associated with steel corrosion. Here, we determined that the CO₂ emissions associated with the steelmaking required to replace corroded steel will be 4.1-9.1% of the total by 2030 considering the European Union and recent U.S. greenhouse gas reduction targets. We suggest that implementing corrosion management best-practices could drastically reduce the greenhouse gas emissions associated with the replacement of corroded steel and emphasize the need for coordinated international efforts.

Sarcoidosis: Pitfalls and Challenging Mimickers

Sarcoidosis, a systemic granulomatous disease of unknown etiology, may mimic other conditions at presentation often resulting in delayed diagnosis. These conditions include infections, neoplasms, autoimmune, cardiovascular, and drug-induced diseases. This review highlights the most common sarcoidosis mimics that often lead to pitfalls in diagnosis and delay in appropriate treatment. Prior to invasive testing and initiating immunosuppressants (commonly corticosteroids), it is important to exclude sarcoid mimickers.

Isolated Pulmonary Valve Endocarditis

Infective endocarditis involving the right side of the heart is typically associated with IV drug abuse and chronic indwelling catheters which commonly involve the tricuspid valve. Isolated pulmonary valve endocarditis (PVE) is a rare clinical entity. We report a rare case of a young woman with a history of end-stage renal disease (ESRD) on hemodialysis through tunneled catheter presenting with persistent coagulase-negative staphylococcus (CoNS) epidermidis bacteremia despite being on appropriate treatment with IV vancomycin for two weeks. Because of the persistent bacteremia, a transesophageal echocardiogram was performed and it revealed a thickened pulmonary valve with 1.8 cm vegetation in the left posterior cusp. She was successfully treated with IV daptomycin course for a total of six weeks. The recommended management for PVE is usually medical treatment with IV antibiotics gauged according to sensitivities of the cultures. Our article highlights the fact that the decision to manage it medically versus surgically can propose a challenge as the guidelines are not very robust. 

Probing hydrogen bonding orbitals: resonant inelastic soft X-ray scattering of aqueous NH3

Resonant inelastic soft X-ray scattering was used to probe the hydrogen bonding orbitals in aqueous ammonia.

Prospective multicenter study on epidemiology of acute kidney injury in the ICU: a critical care nephrology Italian collaborative effort (NEFROINT)

Acute kidney injury (AKI) is an independent risk factor for mortality in critically ill patients whose epidemiology has been made unclear in the past by the use of different definitions across various studies. The RIFLE consensus definition has provided a unifying definition for AKI leading to large retrospective studies in different countries. The present study is a prospective observational multicenter study designed to prospectively evaluate all incident admissions in 10 Intensive Care Units (ICUs) in Italy and the relevant epidemiology of AKI. A simple user-friendly web-based data collection tool was created with the scope to serve for this study and to facilitate future multicenter collaborative efforts. We enrolled 601 consecutive patients into the study; 25 patients with End-Stage Renal Disease were excluded leaving 576 patients for analysis. The median age was 66 (IQR 53-76) years, 59.4% were male, while median SAPS II and APACHE II scores were 43 (IQR 35-54) and 18 (IQR 13-24), respectively. The most common diagnostic categories for ICU admission were: respiratory (27.4%), followed by neurologic (17%), trauma (14.4%), and cardiovascular (12.1%). Crude ICU and hospital mortality were 21.7% and median ICU length of stay was 5 days (IQR 3, 14). Of 576 patients, 246 patients (42.7%) had AKI within 24 hours of ICU admission while 133 developed new AKI later during their ICU stay. RIFLE-initial class was Risk in 205 patients (54.1%), Injury in 99 (26.1%) and Failure in 75 (19.8%). Progression of AKI to a worse RIFLE class was seen in 114 patients (30.8% of AKI patients). AKI patients were older, with higher frequency of common risk factors. 116 AKI patients (30.6%) fulfilled criteria for sepsis during their ICU stay, compared to 33 (16.7%) of non-AKI patients (P<0.001). 48 patients (8.3%) were treated with renal replacement therapy (RRT) in the ICU. Patients were started on RRT a median of 2 (IQR 0-6) days after ICU admission. Among AKI patients, they were started on RRT a median of 1 (IQR 0-4) days after fulfilling criteria for AKI. Median duration of RRT was 5 (IQR 2-10) day. AKI patients had a higher crude ICU mortality (28.8% vs. non-AKI 8.1%, P<0.001) and longer ICU length of stay (median 7 days vs. 3 days [non-AKI], P<0.001). Crude ICU mortality and ICU length of stay increased with greater severity of AKI. Two hundred twenty five patients (59.4% of AKI patients) had complete recovery of renal function, with a SCr at time of ICU discharge which was ≤120% of baseline; an additional 51 AKI patients (13.5%) had partial renal recovery, while 103 (27.2%) had not recovered renal function at the time of death or ICU discharge. Septic patients had more severe AKI, and were more likely to receive RRT with less frequency of renal function recovery. Patients with sepsis had higher ICU mortality and longer ICU stay. The study confirms previous analyses describing RIFLE as an optimal classification system to stage AKI severity. AKI is indeed a deadly complication for ICU patients where the level of severity correlated with mortality and length of stay. The tool developed for data collection resulted user friendly and easy to implement. Some of its features including a RIFLE class alert system, may help the treating physician to collect systematically AKI data in the ICU and possibly may guide specific decision on the institution of renal replacement therapy.

Different patterns of lung recruitment maneuvers in primary acute respiratory distress syndrome: effects on oxygenation and central hemodynamics

BACKGROUND

The aim of this study was to test if different recruitment maneuver (RM) patterns, that achieve the same maximum pressure for the same length of time in humans, have a similar efficacy on alveolar recruitment, intrathoracic vascular pressures and flows, and on cardiac function and ventricular filling.

METHODS

Forty patients were randomly allocated to undergo different RM patterns: sustained inflation (SI) or pressure controlled ventilation (PCV). The RM methods tested are as follows: SI was achieved by raising peak inspiratory pressure to 45 cmH(2)O and sustaining it for 40 seconds. The PCV was set to obtain a 45 cmH(2)O peak inspiratory pressure for 2 minutes, I:E 1:2, PEEP 16 RR 8/min. During the study period, patients were mechanically ventilated to obtain a volume of 6 mL/kg, FiO(2) 0.7, PEEP 14, RR 14, Pplateau < or =30 cmH(2)O according to the ARDSnet trial. All patients were sedated and paralyzed during the study period. All patients were given i.v. norepinephrine. Heart rate, pulse oxymetry, blood pressure, pulmonary artery catheter data (C.I., PVRI, MPAP, PAOP, SvO(2), CVP), and arterial and right heart side venous blood gas analysis data (ph, PaO(2), PaCO(2), SatO(2), HCO(3)(-), SvO(2)) were recorded before and immediately after the lung recruitment maneuver. The static compliance of the respiratory system (CRS) was recorded. Echocardiographic spot evaluations before and after RM were obtained in all cases.

RESULTS

Central venous pressure increased during RM. Mean pulmonary artery pressure, pulmonary capillary wedge pressure and pulmonary vascular resistance index were reduced during PCV RM compared to SI RM (P<0.05). The right ventricle stroke work index decreased to a major extent during PCV RM (P<0.05). The P/F ratio was significantly increased after PCV RM compared to SI RM (P<0.05). PaCO(2) levels were similar in the two groups. Compared to baseline, the Qs/Qt decreased significantly after the PCV recruitment maneuver. Ventricular end-diastolic and end-systolic areas decreased during both RM protocols, but they were decreased to a greater extent after SI RM than after PCV RM (P<0.05). The eccentricity index increased from baseline after the SI RM (P<0.05).

CONCLUSION

Given its comparable, or even superior, performance over the SI RM, we favor the PCV technique over the time-honored SI maneuver.

Relationship between A-line Autoregressive Index, Spectral Entropy and steady state predicted site-effect effective concentrations at 05-50-95 of propofol at different clinical endpoints

AIM

Target controlled infusion intravenous anesthesia is a growing phenomenon. Nowadays, many anesthesiologists feel the need to monitor depth of anesthesia during total intravenous anesthesia, even though it is not a standard technique worldwide. Spectral Entropy (SE) is a relatively new depth of anesthesia index. The aim of this study was to investigate whether predicted site-effect propofol concentrations, A-line Autoregressive Index (AAI) and SE values are useful for predicting loss of verbal contact (LVC) and loss of consciousness (LOC) during steady-state conditions.

METHODS

Forty-four patients scheduled for elective major abdominal surgery were recruited. All patients were unpremedicated. A target controlled infusion of propofol was administered using Schnider's pharmacokinetic model. The initial propofol infusion provided a site-effect concentration of 1.0 mcg mL-1, and was increased stepwise by 1.0 mcg mL-1 every 4 minutes until the concentration reached 6.0 mcg mL-1. A 4 minute interval was chosen to assure that steady state site-effect concentrations were obtained. AAI, SE and propofol site-effect concentrations were recorded when LVC occurred and also when LOC occurred. Population values for predicted site-effect concentrations at the clinical endpoints were estimated and correlated with AAI and SE values.

RESULTS

In our study for LOC the effect-site concentration to include 90% of patients was 5.85 ?mcg mL-1 (5.70-5.90) and 3.4 mcg mL-1 (3.24-3.60) for LVC. In this study, 90% of patients lost verbal contact at an AAI value of 68 (64.6-71.4) and an SE value of 68.2 (66.2-70.2). LOC occurred in 90% of patients at an AAI value of 39.2 (37.2-41.1) and an SE value of 40.2 (38.1-41.3).

CONCLUSIONS

LOC and LVC occur within a defined range of predicted site-effect concentrations. More emphasis should be given to site-effect concentrations. SE and AAI have similar values at different endpoints and similar correlation with Ceprop. AAI and SE are both useful tools in predicting both LVC and LOC.

Deformation of the 27-gauge, 3.5 inch Whitacre spinal needle: macroscopic and microscopic findings

Gross deformation of the spinal needle shaft or the tip may occur during spinal needle insertion. During a one-year period, three cases of severe deformation of 27-gauge, 3.5 inch Whitacre spinal needles (B-Braun) occurred during standard spinal anesthesia in otherwise healthy patients. During this one-year period, we collected cut-bevel-point needles when bone impact occurred and compared them to the points of identical unused needles under a microscope. We believe that these microdeformations may be the cause of anatomical damage. We should be aware of even small resistance during spinal needle insertion because of the possibilities of severe deformation and injury of the anatomical structures, or of dramatic in situ breakage of the spinal needle. We should also be vigilant with respect to bone contact of the spinal needle, because needle points are damaged and can cause dural lacerations with subsequent cerebrospinal fluid leakage.

Postraumatic ARDS: how to place patients who may offer technical problems in a prone position

Ventilation in the prone position is a valid choice in the treatment of trauma patients with acute respiratory distress syndrome (ARDS). Two cases of trauma patients with ARDS treated in the prone position are described. The technique was very easy to use and safe. The prone position technique proved very useful in the treatment of post-traumatic ARDS in these 2 cases.

Severe scombroid fish poisoning syndrome requiring aggressive fluid resuscitation in the emergency department: two case reports

Scombroid fish poisoning (scombrotoxism, scombroid ichthyotoxicosis) is a food-related illness typically associated with the consumption of dark and white meat fish. Two patients presented to the emergency department. Metilprednisone 1000 mg and ranitidine 150 mg were administered initially. A large amount of crystalloids and colloids in in combination with vasoactive drugs were required to maintain normopressure. Levels of histamine and N-methylhistamine were far above the normal mean. Carboxyhemoglobin levels were also tested to exclude a superimposition of carbon monoxide intoxication. In both cases, major symptoms occurred and were treated aggressively. Early goal directed fluid therapy corrected the DO2/VO2 unbalance, due to a distributive pattern of hypovolemic impending shock, and permitted a rapid stabilisation of both patients. It is important to recognize the syndrome as an intoxication (rather than an allergic reaction) so that the source of the toxin can be identified and further cases prevented. It is also important to investigate where the fish was cooked (i.e. in an open space vs. closed space), to exclude the possibility of a concomitant carbon monoxide intoxication, which would require transfer the patient to a hospital facility equipped with a hyperbaric chamber.

BIS - AAI and clinical measures during propofol target controlled infusion with Schnider's pharmacokinetic model

AIM

The A-line autoregressive index (AAI) and the Bispectral Index Score (BIS) are two commercially available indexes of anesthetic depth widely used in clinical practice. The aim of the current study was to compare the accuracy of AAI, BIS, Schnider's predicted effect-site concentration of propofol (Ce propofol) to assess depth of anesthesia.

METHODS

Forty-four patients scheduled for major elective abdominal surgery received target effect-site controlled infusion of propofol. Target effect-site (Ce propofol) was started at 1.5 mug/mL and increased every 4 min by 1.0 microg/mL until 5.5 microg/mL were achieved. At every step sedation level was estimated, using AAI, BIS, Observer's Assessment of Alertness/Sedation scale (OAA/S), loss of eyelash reflex and Ce propofol.

RESULTS

We enrolled 44 patients, 20 males and 24 females, ASA I/II 18/26, 48+/-10 years, 68.2+/-9 kg, 165+/-7.1 cm, body mass index (BMI) 25+/-3.5. At increasing Ce propofol BIS-AAI values decreased progressively (BIS range 97-38) (AAI range 97-17). Values of BIS < or = 50, of AAI < or = 48 and of Ce propofol > or = 5.1 resulted in OAA/S=0, while values of BIS < or = 62, AAI < or = 53 and Ce propofol < or = 3.5 resulted in OAA/S=2. Loss of eyelash reflex occurred when values were BIS < or = 64 and AAI < or 61.

CONCLUSION

BIS, AAI, propofol site effect concentration revealed information on sedation level and consciousness but no gold standard yet exists because of consistent overlap between ''conscious'' and ''not conscious'' states.

Feasibility of Primary Inguinal Hernia Repair with a New Mesh

BACKGROUND

The purpose of this study was to evaluate the feasibility of primary inguinal repair with open tension-free and sutureless technique using a new polypropylene "patch and plug system" (Prolene 3D patch), and the quality of the treatment in terms of reduction of postoperative discomfort.

METHODS

Fifty-six consecutive patients, mean age 54.5+/-11.2 years, with primary unilateral uncomplicated inguinal hernia, were treated in a day-surgery setting. Collected data included: pain scores at 24 hours, 72 hours, and 7, 15, and 30 days after operation, analgesic medications, return to work and to heavy house and/or moderate sporting activities, and quality of life as measured by Short Form 36 health survey questionnaire (SF-36) before the operation and at 6 months follow-up.

RESULTS

Postoperative pain was low: the mean visual analog scale (VAS) scores were 2.8 at 24 h, 1.8 at 72 h, and 0.9, 0.3, and 0.04 at 7, 15, and 30 days, respectively. Analgesic drugs were not used by 66.0% (n=37) of the patients. The mean global time to return to work and to heavy activities was 9.9+/-4.6 and 14.6+/-7.0, days, respectively. Patient satisfaction showed a significant improvement in all SF-36 domain scores at 6 months follow-up (P<0.001). There were no major complications, recurrences, or mortality.

CONCLUSIONS

The new mesh seems to satisfy all requirements of a feasible, reliable, and effective device for repairing primary inguinal hernia with high patient comfort.

Direct experimental evidence of free-fermion antibunching

Fermion antibunching was observed on a beam of free noninteracting neutrons. A monochromatic beam of thermal neutrons was first split by a graphite single crystal, then fed to two detectors, displaying a reduced coincidence rate. The result is a fermionic complement to the Hanbury Brown and Twiss effect for photons.

Radiation Therapy for the Treatment of Unresected Stage I-II Non-small Cell Lung Cancer

STUDY OBJECTIVES

Radiotherapy is considered to be the standard treatment for patients with stage I or II non-small lung cancer who refuse surgery or who are not surgical candidates because of significant comorbidities. To determine whether radiotherapy benefits these patients, we compared the survival of those treated with radiation alone to those left untreated.

METHODS

Using the Surveillance, Epidemiology, and End Results registry, we identified all patients in whom histologically confirmed, stage I and II non-small cell lung cancer had been diagnosed between 1988 and 2001. Among these patients, 4,357 did not undergo surgical resection. Kaplan-Meier survival curves were compared among patients who received and who did not receive radiation therapy. We used Cox regression analysis to evaluate the effect of radiation on survival after adjusting for potential confounders.

RESULTS

The survival of patients with lung cancer who did not undergo resection and had been treated with radiation therapy was significantly better compared to the untreated patients (stage I cancer, p = 0.0001; stage II cancer, p = 0.001). The median survival time of patients with stage I disease who underwent radiotherapy was 21 months compared to 14 months for untreated patients. Stage II patients who received and did not receive radiation therapy had median survival times of 14 and 9 months, respectively. The survival of treated and untreated patients was not significantly different approximately 5 years after diagnosis (stage I disease, 15% vs 14%, respectively; stage II disease, 11% vs 10%, respectively). In multivariate analysis, radiation therapy was significantly associated with improved lung cancer survival after controlling for age, sex, race, and tumor histology.

CONCLUSIONS

These results suggest that radiotherapy is associated with improved survival in patients with unresected stage I or II non-small cell lung cancer. The observed improvement in median survival time was only 5 to 7 months, and radiotherapy did not offer the possibility of a cure.

Relationship between Bispectral Index, electroencephalographic state entropy and effect-site EC 50 for propofol at different clinical endpoints

BACKGROUND

State entropy (SE) is a newly available monitor for depth of anaesthesia. We investigated whether the relationship between predicted effect-site propofol concentration and both bispectral index (BIS) and SE values is useful for predicting loss of verbal contact and loss of consciousness during steady-state conditions.

METHODS

Twenty unpremedicated patients undergoing elective major abdominal surgery were recruited. A target-controlled infusion of propofol was administered using Schneider's pharmacokinetic model. The propofol infusion was set at an initial site-effect concentration of 1.0 microg ml(-1), and increased by 1.0 microg ml(-1) steps every 4 min, up to 6.0 microg ml(-1). A 4-min interval was chosen to ensure that steady-state site-effect concentrations were obtained. Propofol site-effect concentrations and BIS and SE values were recorded at loss of verbal contact (LVC) and loss of consciousness (LOC). Population values for predicted effect-site concentrations at the clinical endpoints were estimated and correlated with BIS and SE values.

RESULTS

For LVC, the effect-site concentration for 90% of patients was 1.1 (1.1-3.2) microg ml(-1) and for LOC 2.8 (2.8-5.65) microg ml(-1). LVC occurred in 90% of patients at a BIS value of 70.2 (70.2-90.2) and an SE value of 60.3 (60.3-75.5) and LOC occurred at a BIS value of 38.2 (38.2-70.4) and an SE value of 42.2 (42.2-60.4).

CONCLUSIONS

LVC and LOC occurred within a defined range of predicted effect-site concentrations. SE had a smaller range than BIS and higher correlation with effect-site concentration and may be more useful than BIS in predicting both LVC and LOC.

Relationship between Bispectral Index, electroencephalographic state entropy and effect-site EC 50 for propofol at different clinical endpoints

BACKGROUND

State entropy (SE) is a newly available monitor for depth of anaesthesia. We investigated whether the relationship between predicted effect-site propofol concentration and Bispectral Index (BIS) and SE values is useful for predicting loss of verbal contact and loss of consciousness during steady-state conditions.

METHODS

Twenty unpremedicated patients undergoing elective major abdominal surgery were recruited. A target-controlled infusion of propofol was administered using Schneider's pharmacokinetic model. The propofol infusion was set at an initial site effect concentration of 1.0 microg ml(-1) and increased by 1.0 microg ml(-1) steps every 4 min up to 6.0 microg ml(-1). A 4-min interval was chosen to ensure that steady-state effect-site concentrations were obtained. Propofol site effect concentrations and BIS and SE values were recorded at loss of verbal contact (LVC) and loss of consciousness (LOC). Population values for predicted effect-site concentrations at the clinical endpoints were estimated and correlated with BIS and SE values.

RESULTS

For LVC, the effect-site concentration for 90% of patients was 1.1 (1.1-3.2) microg ml(-1) and for LOC it was 2.8 (2.8-5.65) microg ml(-1). LVC occurred in 90% of patients at a BIS value of 70.2 (70.2-90.2) and an SE value of 60.3 (60.3-75.5), and LOC occurred at a BIS value of 38.2 (38.2-70.4) and an SE value of 42.2 (42.2-60.4).

CONCLUSIONS

LVC and LOC occurred within a defined range of predicted effect-site concentrations. SE had a smaller range than BIS and greater correlation with effect-site concentration and may be more useful than BIS in predicting both LVC and LOC.

Desflurane and sevoflurane in elderly patients during general anesthesia: a double blind comparison

AIM

To investigate pulmonary wash-out of sevoflurane and desflurane and the quality of recovery from anesthesia in elderly patients.

METHODS

Thirty-six patients aged >65 years, ASA II, were assigned in a double blind fashion to either desflurane (n=18) or sevoflurane (n=18) anesthesia. All received propofol 2 mg/kg and remifentanil 0.2 microg/kg/min for induction and 0.6 mg/kg of rocuronium. When the trachea was intubated volatile anaesthetic was administered. All data were recorded 1, 3, 5, 15, 30 min after intubation and then every 15 min. All data were recorded 1, 2, 3, 4, 5 min after suspension of all agents. Once extubated simple orders and questions were given every minute, times of appropriate response were noted. The patients were then transferred to the recovery room, until discharge to the floor. Postoperative pain control was obtained by a continuous iv infusion of ketorolac 60 mg and tramadol 100 mg. The latter was incremented by supplemental boluses of 50 mg according to patient needs (VAS <4) up to a maximum of 300 mg/24h.

RESULTS

The F(A)/F(A0) ratio was lower in the desflurane group after halogenated agent suspension (p= or <0.05). Desflurane proved to have a faster wash out curve with respect to sevoflurane. Early recovery, as indicated by the time necessary to appropriately answer simple questions after the discontinuation of anesthetics, showed a significant advantage for desflurane (p= or <0.05). VAS was higher in the desflurane group as well as the needs for postoperative analgesia.

CONCLUSIONS

Patients receiving desflurane reported faster recovery from anesthesia but an earlier and more intense perception of pain after surgery.

Proton transfer in heterocycle crystals

We study the proton diffusion process in imidazole-based molecular crystals, which are new candidate materials for fuel cell membranes. These materials are characterized by hydrogen bonded networks of molecules, which provide viable routes for the long-range diffusion of protons. By the application of a recently developed, powerful technique to determine reaction pathways in complex systems, we are able to reproduce the diffusion process in the imidazole crystal and in the more complicated and rigid structure of imidazole 2-ethyleneoxide. Our results cast new light on the atomistic details of the molecular rearrangements sustaining the ionic diffusion.

Tumour necrosis factor in sarcoidosis and its potential for targeted therapy

Tumour necrosis factor (TNF)-alpha is a potent cytokine involved in the inflammatory reactions of many acute and chronic diseases. Recently, agents that block TNFalpha either directly or indirectly have been successful in the treatment of a variety of immune-mediated inflammatory disorders including rheumatoid arthritis and Crohn's disease. Sarcoidosis is an immune-mediated inflammatory disorder characterised by the formation of granulomas. TNFalpha is important in the initiation and perpetuation of inflammation in sarcoidosis, contributing to the initiation of granulomas and the progression of fibrosis, as well as to nongranulomatous inflammation. Various agents used to treat sarcoidosis affect TNF, including the most widely used drug class, corticosteroids, which are usually effective in blocking TNFalpha release from cells. Other agents that nonspecifically inhibit TNFalpha release include methotrexate, azathioprine and pentoxifylline. Specific TNF-antagonising biological agents such as infliximab and etanercept are being tested in patients with sarcoidosis, with mixed success. Infliximab has been shown to produce clinical improvement and reduce the requirement for corticosteroids in a small number of patients with sarcoidosis. However, as infliximab can be associated with reactivation of tuberculosis, which could be mistaken as worsening sarcoidosis, it should be used with caution in this patient group.

Peri-intubation cardiovascular response during low dose remifentanil or sufentanil administration in association with propofol TCI. A double blind comparison

AIM

The aim of this study was to compare the effects on cardiovascular modifications induced by tracheal intubation when low dose infusion of remifentanil or sufentanil are used in association with propofol target controlled infusion.

METHODS

Sixty normotensive, ASA I-II-III, Mallampati Score <3 undergoing general anaesthesia for major elective abdominal surgery, received i.m. midazolam (0.05 mg/kg) and atropine (0.01 mg/kg) 30 min before induction. They were randomly divided in a double-blind fashion into two groups receiving for induction respectively target controlled infusion of propofol (site-effect 3.0 microg/ml) and sufentanil (0.01 microg/kg/min) or remifentanil (0.1 microg/kg/ min) infusion. Rocuronium (0.6 mg/kg) was administered. Following intubation, the lungs were mechanically ventilated with an oxygen/air mixture.

RESULTS

Bispectral index score and haemodynamic variables were recorded at baseline, after induction, during intubation and 1-3-5 min after the trachea was intubated. No differences in systolic and diastolic arterial pressure were observed in the sufentanil group, while the remifentanil group showed transient systolic and diastolic variations after intubating manoeuvers. The heart rate and bispectral index score were not affected in either group.

CONCLUSION

In healthy normotensive patients the use of a small dose of either remifentanil or sufentanil after standard midazolam premedication, proved to be an effective strategy to blunt the cardiovascular response to intubation.

Spinal anaesthesia using hyperbaric 0.75% vs hyperbaric 1% bupivacaine: a double blind comparison

AIM

The aim of this study was to compare the anesthetic effects, potency and postoperative outcome of 0.75% and 1% concentrations of hyperbaric bupivacaine in selective spinal anesthesia.

METHODS

We enrolled 40 patients in a double blind fashion in 2 groups (A= 0.75% bupivacaine; B= 1% bupivacaine). Demographic data were respectively for Groups A and B: age 40.6+/-16 and 67+/-16, weight 74+/-14.4 and 68+/-10.2; sex 10M/10F and 6M/14F; ASA I-II 11/9 and 14/6. All patients received 11.25 mg bupivacaine. In all cases a 27G Whitacre needle was introduced at L1-L2, L2- L3, L3-L4 introduced with a midline approach. Time to onset and offset of sensitive and motor block, dermatomeric extension non invasive blood pressure, heart rate, ephedrine dose, deambulation time, diuresis time and request for supplemental analgesia were recorded.

RESULTS

No statistically significant differences between the 2 groups for demographic data were found. Group B revealed a faster onset and a more adequate dermatomeric extension (4.1+/-0.8 min vs 6.5+/-1.2 min). Both concentrations guaranteed good hemodynamic stability. Motor offset times were 115.8+/-145 min and 142+/-4.8 min respectively in groups A and B. Sensitive offset times were 197.5+/-12 min and 168+/-5.2 min respectively in groups A and B. No statistically relevant differences were noticed for intraoperative Bromage, sensitive block or for postoperative motor and sensitive offset time, diuresis time and deambulation time. There are no advantages of 1% hyperbaric bupivacaine over 0.75% for selective spinal anesthesia, while several disadvantages presented shorter duration of postoperative analgesia and higher incidence of headache.

Small doses of remifentanil and alfetanil in continuous total intravenous anesthesia in major abdominal surgery. A double blind comparison

AIM

The purpose of this study was to test the safety and efficacy of small doses of remifentanil and alfentanil in a continuous total intravenous anesthesia technique for patients undergoing major abdominal surgery.

METHODS

Sixty patients were enrolled in the study, and received in a double blind fashion either remifentanil (0.1 microg/kg/min) or alfentanil (alfentanil 0.75 microg/kg/min) in association with propofol (12 mg/kg/h at induction; 6-9 mg/kg/h for maintenance) and cisatracurium. Hemodynamic data, hypnosis monitoring data (Bispectral Index Score), ventilatory parameters and settings, drug utilisation were monitored during stress moments and during all the intraoperative period. Patients were evaluated also in the first 6 postoperative hours.

RESULTS

Mean amount of propofol for induction (BIS<60) was lower in the remifentanil group than in the alfentanil group. Significantly fewer patients receiving remifentanil responded to intubation in comparison with patients receiving alfentanil in terms of non invasive blood pressure (>30 mmHg) and heart rate variations. Significantly more patients receiving alfentanil had 1 or more responses to surgery. Incidence of hypotension was significantly higher in patients receiving remifentanil. There were no differences between the 2 groups in the times for spontaneous respiration, adequate respiration, adequate responsivness (OAA/s=5) and discharge from the recovery room. Time to extubation resulted slightly shorter (p<0.05) in patients who received remifentanil.

CONCLUSIONS

The use of remifentanil and alfentanil in association with propofol, in a continuous infusion total intravenous anesthesia technique, demonstrated to be safe and reliable strategies.

Thromboembolism in pregnancy: a new temporary caval filter

BACKGROUND

Our aim was to check out the advantages of temporary caval filtration in pregnancy with a retrievable filter: Tempofilter (tCF).

METHODS

During a period of 2 years we implanted tCF in four patients at the third pregnancy trimester with serious acute deep venous thrombosis (DVT) of the lower limbs for prophylaxis of pulmonary thromboembolic disease (TED) in the pre-partum, during Caesarian section (CS), and in the post-partum period. tCF has been placed percutaneously in local anaesthesia using the Seldinger technique and under image intensifier control. All procedures were performed in a polyvalent ICU.

RESULTS

tCF positioning was always easy. No complications linked to the adopted technique occurred. No incidence of pulmonary embolism was reported (PE). The permanence period of tCF in situ was 14 to 29 days (mean+/-SD: 21+/-6). The CS always took place without complications either for the patient or for the foetus.

CONCLUSIONS

The combined use of tCF and an anti-coagulating therapy resulted in an effective prophylaxis of TED for the pregnant woman without any interferences with CS and with no consequence as for permanent endovascular prosthesis for the young patient herself.

Myocarditis and pericarditis with tamponade associated with disseminated tuberculosis

Tuberculous involvement of the myocardium is relatively rare. Tuberculous pericarditis with tamponade and myocarditis in a young woman with no evidence of immunosuppression and disseminated tuberculosis is described. Three distinct forms of myocardial involvement are recognized: nodular tubercles (tuberculomas) of the myocardium; miliary tubercles of the myocardium; and an uncommon diffuse infiltrative type. The myocardium is involved by a hematogenous route, by lymphatic spread or contiguously from the pericardium. The diagnosis can be made by endomyocardial biopsy if clinical suspicion is strong and echocardiographic findings are suggestive. Antituberculosis drugs may be curative. With an increasing prevalence of tuberculosis, the possibility of potentially lethal myocardial tuberculosis is important to consider.

Intravascular hemolysis after mitral and aortic valve replacement with different types of mechanical prostheses

Heart valve replacement with mechanical prosthesis is associated with mild intravascular hemolysis. In this study we evaluated the incidence of hemolysis in patients with different combinations of two mechanical valves. Between 1974 and 1996, 680 patients underwent mitral and aortic valve replacement with mechanical prostheses; we selected 90 patients, divided into six groups according to the prosthetic model (Group A, ball and tilting disc; Group B, ball and bileaflet; Group C, tilting disc and tilting disc; Group D, tilting disc and bileaflet; Group E, bileaflet and tilting disc; Group F, bileaflet and bileaflet; respectively, in mitral and aortic position). Blood tests were performed to check blood hemoglobin, serum lactic dehydrogenase, percent-correlated reticulocyte fraction, serum haptoglobin, and schistocytes. Chi square test was performed for categorical data. ANOVA and Bonferroni tests were performed in order to evaluate significant statistical differences between media and variance of the hematological data. A mild degree of intravascular hemolysis was observed in 30% of patients with double mechanical prostheses. LDH values were above the normal values in all groups, although a significant difference was found only between Group B versus Groups C and D. Reticulocytes and schistocytes and serum haptoglobin values were within the normal range and no differences were found between the groups. Low levels of blood hemoglobin were found in Groups D and F. The difference was statistically significant when compared with Groups A and E. In conclusion, hemolysis is frequent but never severe in patients with mitral and aortic mechanical prostheses. A higher incidence of subclinical hemolysis was found in patients with bileaflet valves regardless of the position of the implant.

Monitoring of fibrin and fibrinogen degradation products (FDP) in the cerebrospinal fluid of patients with subarachnoid haemorrhage due to ruptured aneurysm. Report of 55 cases

Fibrin and fibrinogen degradation products in the cerebrospinal fluid (CSF-FDP) were first studied in a group of 29 patients observed during the first and the second week after subarachnoid hemorrhage (SAH), then in a second group of 26 patients for a total of 55 patients. In the latter group only the first FDP value obtained as soon as possible after SAH was taken in consideration. In the whole series of 55 patients several noteworthy factors were found: 1) FDP determination should be performed as soon as possible after SAH; 2) CSF-FDP at or above 40, 80 micrograms/ml was found both in the patients with severe neurological deficits and in those with cerebral ischemia (statistically significant); 3) the significance of CSF-FDP in patients who rebled was also evaluated. In conclusion CSF-FDP could be considered useful in predicting cerebral ischemia.

The gene for the alpha i1 subunit of human guanine nucleotide binding protein maps near the cystic fibrosis locus

The gene for the alpha i1 subunit of human guanine nucleotide binding (G) protein was mapped by in situ hybridization to chromosome 7 at band q21. The regional chromosomal location of the human alpha i1 gene was confirmed using human/mouse somatic-cell hybrid lines containing portions of human chromosome 7. Because the alpha i1 gene mapped near the cystic fibrosis locus and because an abnormal G protein might be expected to contribute to the pathophysiology of this disease, the alpha i1 gene was mapped with respect to the cystic fibrosis locus as defined by the Met oncogene and anonymous DNA marker pJ3.11. The location of the alpha i1 gene proved to be distinct from that of the cystic fibrosis locus.

The diagnosis, pathogenesis, and treatment of adult respiratory distress syndrome

ARDS is well recognized as a major medical emergency resulting in respiratory failure and refractory hypoxemia. The risk factors and attack rate of ARDS have been identified and principles of management established. The pathogenesis involves the release of toxic cell products that damage the air-blood interface, resulting in pulmonary edema, loss of functioning lung units, and reduced compliance. Today, management is supportive and results in the salvage of approximately 40% of patients suffering ARDS from all causes. Certain roentgenographic features can be identified in both acute and late phases of ARDS. The prognosis of survivors is favorable in the long term.