Effect of chlorhexidine skin disinfection and retrosternal gentamicin sponge on post-sternotomy mediastinitis: results from a prospective controlled registry of 2340 patients.

BACKGROUND: Reducing post-sternotomy mediastinitis (PSM) requires incorporating multiple methods. However, the independent effects of these measures are not well studied. AIM: To evaluate the independent effect of preoperative disinfection using isopropyl alcohol (IPA)-chlorhexidine gluconate (CHG) and the topical application of a retrosternal gentamicin collagen sponge at wound closure on reducing PSM. METHODS: From October 2012 to August 2014, 2340 patients were included in this prospective, controlled registry. Patients were divided into four groups. In groups 1 and 2, the skin was disinfected with IPA, and in groups 3 and 4, the skin was disinfected with IPA-CHG. A retrosternal gentamicin collagen sponge was used in groups 2 and 4. Freedom from PSM up to the 30th postoperative day was the primary endpoint. The secondary endpoint was freedom from any surgical site dehiscence. A stepwise regression model was made to reveal the independent factors associated with lower incidence of PSM. FINDINGS: There were significant differences in outcome among the groups (P < 0.0001). Primary healing was highest in group 4 (91.4%), which showed the lowest rate for mediastinitis (0.9%). Multivariate analysis showed that the use of CHG and a gentamicin sponge was statistically significant (P = 0.026 and 0.013, respectively). The other significant independent factors were valve operation (P = 0.001), body mass index >30 kg/m2 (P = 0.001), preoperative stroke (P = 0.005), and blood transfusion (P = 0.022). CONCLUSION: Preoperative skin disinfection with IPA-CHG is superior to only IPA, and it should be recommended. The addition of a retrosternal gentamicin-releasing sponge further reduces the rate of mediastinitis.

The differences in testicular volumes in boys 8-36 months old with undescended, retractile and hydrocele testis--usefulness of scrotal screening ultrasound.

PURPOSE: The aim of the study was quantitative and qualitative assessments of scrotal abnormalities diagnosed in boys 8 to 36 months old during ultrasound screening and estimation if these abnormalities influence testes volume. MATERIALS AND METHODS: High frequency scrotal ultrasound was performed in 1448 patients aged 8-36 months as additional exam during screening ultrasound program for children including cervical and abdominal ultrasound. The mean age of examined boys was 17 months. For further analysis the children were divided in 5 age groups. RESULTS: The abnormalities in scrotal ultrasound were found in 20.1% of boys. Undescended, cryptorchid testes were found in 4.8% of patients, mobile testicle in 7.6% and hydrocele in 2.8%. The volume of undescended testes was statistically lower than volume of the descended testes in 3 youngest groups of boys (p=0.003-0.011). The volume of mobile testicles did not increase with age, while in patients with hydrocele the testicular volume decreased with age. CONCLUSION: Scrotal screening ultrasound performed in boys up to 3 years old may deliver information about the number and type of existing pathologies as well as their influence on the testicular volume. The volume of the pathological testes was lower than the volume of the normal ones. Improper growth of testes may potentially have important clinical implication for the function of testes in the future.

Indirect MR-arthrography in osteochondral autograft and crushed bone graft with a collagen membrane--correlation with histology.

OBJECTIVE: To analyze the spectrum of findings in indirect MR-arthrography following osteochondral autograft transfer system (OATS) and crushed bone graft using a magnetic resonance imaging (MRI) scoring and grading system in relation to histology as the standard of reference. MATERIALS AND METHODS: Iatrogenic lesions were set at ovine condylar facets (n=6/group), treated with OATS or crushed bone graft. 1.5 T MRI was performed 6 months after surgery using PD-weighted (w fat saturated (fs) fast spin echo (FSE), T1-w 2D, and 3D fs gradient echo (GE) sequences 30 min. after i.v. Gd-DTPA administration and passive joint exercise. The repair tissue was evaluated by two independent radiologists. The MR findings were compared to histology. RESULTS: In all cases, MRI and histologic grading correlated well and showed significant superior repair in OATS at 6 months (p<0.05), reproducing the original articular contour and a good subchondral restoration. FsT1-w3DGE proved most appropriate identifying characteristic post-operative findings: the OATS group demonstrated bone marrow edema at the donor site and the graft/host interface showed significant enhancement in indirect MR-arthrography, indicating fibrocartilage. After crushed bone graft, we found an irregular structure and significant contrast uptake, consistent with remnants of bone grafts surrounded by inflammatory tissue. CONCLUSION: Indirect MR-arthrography is an accurate, non-invasive monitoring tool following OATS and crushed bone graft as the MRI scoring and grading system allows a reliable evaluation of normal and pathological osteochondral repair with a high histologic correlation.

MMDB: 3D structure data in Entrez.

Three-dimensional structures are now known for roughly half of all protein families. It is thus quite likely, in searching sequence databases, that one will encounter a homolog with known structure and be able to use this information to infer structure-function properties. The goal of Entrez's 3D structure database is to make this information accessible and useful to molecular biologists. To this end, Entrez's search engine provides three powerful features: (i) Links between databases; one may search by term matching in Medline((R)), for example, and link to 3D structures reported in these articles. (ii) Sequence and structure neighbors; one may select all sequences similar to one of interest, for example, and link to any known 3D structures. (iii) Sequence and structure visualization; identifying a homolog with known structure, one may view a combined molecular-graphic and alignment display, to infer approximate 3D structure. Entrez's MMDB (Molecular Modeling DataBase) may be accessed at: http://www.ncbi.nlm.nih.gov/Entrez/structure.html

MMDB: Entrez's 3D structure database.

The three dimensional structures for representatives of nearly half of all protein families are now available in public databases. Thus, no matter which protein one investigates, it is increasingly likely that the 3D structure of a homolog will be known and may reveal unsuspected structure-function relationships. The goal of Entrez's 3D-structure database is to make this information accessible and usable by molecular biologists (http://www.ncbi.nlm.nih.gov/Entrez). To this end Entrez provides two major analysis tools, a search engine based on sequence and structure 'neighboring' and an integrated visualization system for sequence and structure alignments. From a protein's sequence 'neighbors' one may rapidly identify other members of a protein family, including those where 3D structure is known. By comparing aligned sequences and/or structures in detail, using the visualization system, one may identify conserved features and perhaps infer functional properties. Here we describe how these analysis tools may be used to investigate the structure and function of newly discovered proteins, using the PTEN gene product as an example.

Administration of drugs outside of Product Licence: awareness and current practice.

An interactive audience response system was used to collect information from members of the Obstetric Anaesthetists' Association at the 1997 Annual Meeting about the drug use that is unsupported by the Product Licence. The responses confirm that both licensed and unlicensed drugs are widely used in clinical practice outside the limitations imposed by Product Licence. The commonest types of unlicensed administration in obstetric anaesthetic practice are the use of mixtures and epidural or spinal administration of opioids. Despite widespread awareness of the subject, there appears to be considerable ignorance about the indications for which many commonly used drugs are licensed, even amongst a specialist audience. A majority of audience members expressed a view that the OAA should play a pro-active role, either by polling members about their current practice, or by issuing guidelines on reasonable drug practice in obstetric anaesthesia, or both. Potential implications of these are discussed.

Accidental oral poisoning with carbamate in a 26-year-old patient.

Acute, accidental, oral poisoning with carbofuran in a chronic alcoholic was presented. In clinical picture muscarinic and nicotinic symptoms dominated. Toxicological examination revealed non acetylcholinesterase activity. A role of an interview and physical symptoms in diagnosing the poisoning with cholinesterase inhibitors, a specific treatment conduct and its side effects were discussed. So far six cases of poisoning with cholinesterase inhibitors have been treated at II Department of Internal Diseases and Acute Poisoning in Tarnów. The case presented below was characteristic for a considerable intensification of side effects during the treatment conduct. It was the reason for presenting this case.

Adequacy of information and acceptability of pain relief as assessed by a postpartum questionnaire.

An audit cycle has been completed looking at the availability of information about different types of anaesthesia in labour, their usage and the degree of maternal satisfaction. The initial audit 7 years ago led to the production of an information leaflet on pain relief in labour. The current audit (1996) demonstrated that the majority of patients receive the leaflet and find the information useful. The leaflet may have helped improve satisfaction and selection of analgesia in primigravide. However, the leaflet needs updating to include some information on caesarean section now that this has become such a common form of delivery.

Surprising similarities in structure comparison.

Examination of a protein's structural 'neighbors' can reveal distant evolutionary relationships that are otherwise undetectable, and perhaps suggest unsuspected functional properties. In the past, such analyses have often required specialized software and computer skills, but new structural comparison methods, developed in the past two years, increasingly offer this opportunity to structural and molecular biologists in general. These methods are based on similarity-search algorithms that are fast enough to have effectively removed the computer-time limitation for structure-structure search and alignment, and have made it possible for several groups to conduct systematic comparisons of all publicly available structures, and offer this information via the World Wide Web. Furthermore, and perhaps surprisingly given the difficulty of the structure-comparison problem, these groups seem to have converged on quite similar approaches with respect to both fast search algorithms and the identification of statistically significant similarities.

Threading a database of protein cores.

We present an analysis of 10 blind predictions prepared for a recent conference, "Critical Assessment of Techniques for Protein Structure Prediction." The sequences of these proteins are not detectably similar to those of any protein in the structure database then available, but we attempted, by a threading method, to recognize similarity to known domain folds. Four of the 10 proteins, as we subsequently learned, do indeed show significant similarity to then-known structures. For 2 of these proteins the predictions were accurate, in the sense that a similar structure was at or near the top of the list of threading scores, and the threading alignment agreed well with the corresponding structural alignment. For the best predicted model mean alignment error relative to the optimal structural alignment was 2.7 residues, arising entirely from small "register shifts" of strands or helices. In the analysis we attempt to identify factors responsible for these successes and failures. Since our threading method does not use gap penalties, we may readily distinguish between errors arising from our prior definition of the "cores" of known structures and errors arising from inherent limitations in the threading potential. It would appear from the results that successful substructure recognition depends most critically on accurate definition of the "fold" of a database protein. This definition must correctly delineate substructures that are, and are not, likely to be conserved during protein evolution.

Threading analysis suggests that the obese gene product may be a helical cytokine.

The ob gene encodes a protein that, in mutant form, is associated with obesity and type II diabetes in mice. Sequence analysis has revealed no similarities to other proteins, however, and no clues as to possible functions. The possibility nonetheless remains that ob is functionally or ancestrally related to other proteins, whose sequences are divergent to the point that only a comparison of three-dimensional structures might detect relationship. To explore this possibility, we conduct a 'threading' search of a 3-dimensional structure database, to determine whether the ob protein might adopt a fold similar to any known structure. This search reveals that the ob sequence is compatible, at a significance level of P < 0.05, with structures from the family of helical cytokines that includes interleukin-2 and growth hormone. A structural model of ob based upon these results is physically and biologically plausible and leads to testable predictions, including the prediction that ob may activate the JAK-STAT pathway, via binding to a receptor resembling those of the cytokine family.

Balanced analgesia with intravenous ketorolac and patient-controlled morphine following lower abdominal surgery.

STUDY OBJECTIVE: To investigate the efficacy, opioid-sparing effects and any reduction in adverse events of a continuous intravenous (i.v.) infusion of ketorolac following lower abdominal surgery. DESIGN: Randomized, double-blind, placebo-controlled, parallel-group study. SETTING: Inpatient elective gynecologic surgical patients. PATIENTS: 60 ASA physical status I or II patients aged 18 to 70 years scheduled for elective abdominal hysterectomy. INTERVENTIONS: Following standardized preparation and anesthesia, continuous i.v. infusions of either ketorolac or placebo were administered for 24 hours postoperatively with a patients' standardized postoperative protocol. Supplementary analgesia was administered by an i.v. patient-controlled analgesia (PCA) system. MEASUREMENTS AND MAIN RESULTS: A significantly lower proportion of the patients in the ketorolac group (6%) rated their pain at 24 hours as moderate or severe compared with patients in the placebo group (34%) (p = 0.04). Mean 24-hour morphine consumption was significantly lower in the ketorolac group (43 mg; SEM 5 mg) compared with the placebo group (55 mg SEM 5 mg) (p = 0.02). There was no significant difference in the incidence of postoperative hypoxemia between the groups with respect to mean times per hour spent with oxygen saturation (SPO2) less than 85%, more than 85% but less than 90%, or more than 90% but less than 94%, mean hourly SPO2, or the incidence and duration of severe hypoxemic episodes. Nausea and vomiting were the only significant adverse events, and they occurred in 30% of patients in both groups. CONCLUSION: Intravenous infusion of ketorolac combined with morphine delivered via a PCA device would appear to be a valuable method of providing balanced analgesia following lower abdominal surgery.

Extradural infusion analgesia for postoperative pain relief.

We describe 4-yr experience providing extradural infusion analgesia in a district hospital for treatment of postoperative pain. A total of 770 patients recovering from major surgery were treated on general surgical wards between April 1989 and March 1993. The results of a retrospective audit showed that pain control, assessed with both a visual analogue scale (VAS score (0-10 cm)) and a verbal rating scale (VRS), was good. At rest, more than 80% of patients scored pain as absent or mild (VAS score 0-3) during the first 24 h, with only 4% experiencing severe pain (VAS score 7-10). On movement, 50% of patients had good pain control (VAS score 0-3) while 20% of patients experienced severe pain (VAS score 7-10). Minor complications such as emetic sequelae and pruritus were common; these conditions were mild and rarely required treatment. Hypotension (< 100 mm Hg) occurred in 34% of patients in the first 24 h. Ventilatory frequencies of 8 b.p.m. or less occurred in 2.6% of patients. Four patients (0.52%) developed severe respiratory depression. These patients demonstrated increased sedation but only one had a low ventilatory frequency. Three patients died while receiving extradural infusion analgesia.

Hamiltonians for protein tertiary structure prediction based on three-dimensional environment principles.

We describe a computational approach to protein tertiary structure prediction that combines ideas from the three-dimensional (3D) profile method of Bowie, Lüthy and Eisenberg and the associative memory Hamiltonians of Friedrichs and Wolynes. The ultimate goal of our work is to extend and generalize the capabilities of these heuristics so as to be able to predict novel structures that might be found in nature or designed proteins. In our approach we approximate the interactions between residues through a pseudo-potential function similar to an associative memory Hamiltonian. This function is constructed based on 3D environment principles. Favorable inter-residue contacts for each residue in a target protein are inferred by using 3D environment propensities of the residues and a collection of 3D environment templates derived from a dataset of protein crystal structures. A Hamiltonian encoding this information is used to guide an optimization phase via molecular dynamics with annealing, which then leads to the folded structure. With our algorithm we can recover the structure of dataset proteins and have also succeeded in constructing the fold for a protein with little sequence similarity to any dataset protein.

Assessing introduction of spinal anaesthesia for obstetric procedures.

To assess the impact of introducing spinal anaesthesia for obstetric operative procedures on use of general anaesthesia and quality of regional anaesthesia in a unit with an established epidural service a retrospective analysis of routinely collected data on method of anaesthesia, efficacy, and complications was carried out. Data were collected from 1988 to 1991 on 1670 obstetric patients requiring an operative procedure. The introduction of spinal anaesthesia in 1989 significantly reduced the proportion of operative procedures performed under general anaesthesia, from 60% (234/390) in 1988 to 30% (124/414) in 1991. The decrease was most pronounced for manual removal of the placenta (88%, 48/55 v 9%, 3/34) and emergency caesarean section (67%, 129/193) v 38%, 87/229). Epidural anaesthesia decreased in use most significantly for elective caesarean section (65%, 77/118 v 3% 3/113; x2=139, p<0.0001). The incidence of severe pain and need for conversion to general anaesthesia was significantly less with spinal anaesthesia (0%, 0/207 v 3%, 5/156; p<0.05). Hypotension was not a problem, and the incidence of headache after spinal anaesthetic decreased over the period studied. Introducing spinal anaesthesia therefore reduced the need for general anaesthesia and improved the quality of regional anaesthesia.

Hypoxaemia and pain relief after lower abdominal surgery: comparison of extradural and patient-controlled analgesia.

We have examined postoperative pain in patients allocated randomly to receive extradural bolus diamorphine 3.6 mg, extradural infusion of 0.15% bupivacaine with 0.01% diamorphine or patient-controlled i.v. administration of diamorphine at a maximum rate of 1 mg per 5 min, after total abdominal hysterectomy. Extradural infusion analgesia produced the smallest pain scores from 12 to 24 h after surgery (P < 0.05). More patients in the extradural infusion group were moderately hypoxaemic (SpO2 < 90% > 12 min h-1) after operation, compared with the two other groups (P < 0.05). The group using patient-controlled analgesia received more diamorphine and suffered a greater incidence of emetic sequelae (P < 0.05).

Hypoxaemia and pain relief after upper abdominal surgery: comparison of i.m. and patient-controlled analgesia.

Forty patients recovering from upper abdominal surgery were allocated randomly to receive i.m. morphine 0.15 mg kg-1 as required or patient-controlled analgesia (PCA), with i.v. morphine 1 mg and a 5-min lock out time. Arterial oxygen saturation (SpO2) was measured continuously the night before and for 24 h immediately after surgery. A significantly greater proportion of patients in the PCA group (nine of 19) rated their analgesia as excellent compared with the i.m. group (two of 20) (P < 0.05). There was no significant difference in the incidence of postoperative hypoxaemia in the two treatment groups. Severe postoperative hypoxaemia (SpO2 < 85% for more than 6 min h-1) was seen in three patients receiving i.m. analgesia and one patient in the PCA group.