Guidelines 2000 for colon and rectal cancer surgery

BACKGROUND

Oncologic resection techniques affect outcome for colon cancer and rectal cancer, but standardized guidelines have not been adopted. The National Cancer Institute sponsored a panel of experts to systematically review current literature and to draft guidelines that provide uniform definitions, principles, and practices.

METHODS

Methods were similar to those described by the American Society of Clinical Oncology in developing practice guidelines. Experts representing oncology and surgery met to review current literature on oncologic resection techniques for level of evidence (I-V, where I is the best evidence and V is the least compelling) and grade of recommendation (A-D, where A is based on the best evidence and D is based on the weakest evidence). Initial guidelines were drafted, reviewed, and accepted by consensus.

RESULTS

For the following seven factors, the level of evidence was II, III, or IV, and the findings were generally consistent (grade B): anatomic definition of colon versus rectum, tumor-node-metastasis staging, radial margins, adjuvant R0 stage, inadvertent rectal perforation, distal and proximal rectal margins, and en bloc resection of adherent tumors. For another seven factors, the level of evidence was II, III, or IV, but findings were inconsistent (grade C): laparoscopic colectomy; colon lymphadenectomy; level of proximal vessel ligation, mesorectal excision, and extended lateral pelvic lymph node dissection (all three for rectal cancer); no-touch technique; and bowel washout. For the other four factors, there was little or no systematic empirical evidence (grade D): abdominal exploration, oophorectomy, extent of colon resection, and total length of rectum resected.

CONCLUSIONS

The panel reports surgical guidelines and definitions based on the best available evidence. The availability of more standardized information in the future should allow for more grade A recommendations.

The ars operon of Escherichia coli confers arsenical and antimonial resistance

The chromosomally encoded arsenical resistance (ars) operon subcloned into a multicopy plasmid was found to confer a moderate level of resistance to arsenite and antimonite in Escherichia coli. When the operon was deleted from the chromosome, the cells exhibited hypersensitivity to arsenite, antimonite, and arsenate. Expression of the ars genes was inducible by arsenite. By Southern hybridization, the operon was found in all strains of E. coli examined but not in Salmonella typhimurium, Pseudomonas aeruginosa, or Bacillus subtilis.

Virtual reality in the treatment of spider phobia: a controlled study

This study explored whether virtual reality (VR) exposure therapy was effective in the treatment of spider phobia. We compared a treatment condition vs. a waiting list condition in a between group design with 23 participants. Participants in the VR treatment group received an average of four one-hour exposure therapy sessions. VR exposure was effective in treating spider phobia compared to a control condition as measured with a Fear of Spiders questionnaire, a Behavioural Avoidance Test (BAT), and severity ratings made by the clinician and an independent assessor. Eighty-three percent of patients in the VR treatment group showed clinically significant improvement compared with 0% in the waiting list group, and no patients dropped out. This study shows that VR exposure can be effective in the treatment of phobias.

Melanocortin peptides inhibit production of proinflammatory cytokines and nitric oxide by activated microglia

Inflammatory processes contribute to neurodegenerative disease, stroke, encephalitis, and other central nervous system (CNS) disorders. Activated microglia are a source of cytokines and other inflammatory agents within the CNS and it is therefore important to control glial function in order to preserve neural cells. Melanocortin peptides are pro-opiomelanocortin-derived amino acid sequences that include alpha-melanocyte-stimulating hormone (alpha-MSH) and adrenocorticotropic hormone (ACTH). These peptides have potent and broad anti-inflammatory effects. We tested effects of alpha-MSH (1-13), alpha-MSH (11-13), and ACTH (1-24) on production of tumor necrosis factor alpha (TNF-alpha), interleukin-6 (IL-6), and nitric oxide (NO) in a cultured murine microglial cell line (N9) stimulated with lipopolysaccharide (LPS) plus interferon gamma (IFN-gamma). Melanocortin peptides inhibited production of these cytokines and NO in a concentration-related fashion, probably by increasing intracellular cAMP. When stimulated with LPS + IFN-gamma, microglia increased release of alpha-MSH. Production of TNF-alpha, IL-6, and NO was greater in activated microglia after innmunoneutralization of endogenous alpha-MSH. The results suggest that alpha-MSH is an autocrine factor in microglia. Because melanocortin peptides inhibit production of pro-inflammatory mediators by activated microglia they might be useful in treatment of inflammatory/degenerative brain disorders.

Factors affecting mortality rates in patients with abdominal vascular injuries

BACKGROUND

Major vessel injury is seen in 5% to 25% of patients admitted to hospitals with abdominal trauma, and this is the most common cause of death in these patients.

METHODS

Data on 470 patients with abdominal vascular injuries seen at a Level I trauma center were reviewed retrospectively.

RESULTS

The overall mortality rate was 45%. The incidence of various types of trauma were blunt in 51 patients (11%), gunshot wounds in 329 patients (70%), shotgun wounds in 21 patients (4%), and stab wounds in 69 patients (15%). The three vessels with the highest mortality rates were aorta (at and proximal to the renals) (32 of 35 [91%]), hepatic veins and/or retrohepatic vena cava (36 of 41 [88%]), and portal vein (25 of 36 [69%]). The most significant risk factors (p < 0.001) for death were a trauma score of 9 or less, initial operating room (OR) systolic blood pressure (SBP) < 90 mm Hg, final OR core temperature < 34 degrees C, 10 or more blood transfusions in the first 24 hours, and an initial emergency department SBP < 70 mm Hg. Of 120 patients with an initial OR SBP < 70 mm Hg, 103 (86%) died. Of 29 patients with a good response to a prelaparotomy thoracotomy with thoracic aortic cross-clamping (SBP > 90 mm Hg within 5 minutes), 11 (38%) survived. Of the remaining 87 patients, only 6 (7%) survived (p = 0.01).

CONCLUSION

Rapid control of bleeding sites (to keep blood transfusions to < 10 units) and urgent correction of hypothermia seem to be the main factors improving survival over which the surgeon has some control.

Increased plasma nitrites in migraine and cluster headache patients in interictal period: basal hyperactivity of L-arginine-NO pathway?

Nitrite concentrations in plasma were investigated in a population of migraine and cluster headache patients and a group of healthy non-headache controls. A hundred migraine patients and 69 cluster headache patients in the interictal period, and 112 controls, were studied. Significantly higher nitrite concentrations were found in migraine patients, with and without aura, and cluster headache patients, in remission and cluster phase, than in controls. These findings suggest that a basal dysfunction in the L-arginine-NO pathway may be involved in the peripheral mechanisms predisposing subjects with neurovascular headaches to individual attacks.

Complete wetting on a linear wedge

We have measured the growth of liquid films of Ar adsorbed on well defined arrays of microscopic linear wedges sculpted on thin Si wafers and on a stainless steel disk. On these patterns, a clear cross-over from a planarlike to a geometry dependent growth behavior is observed. This crossover is found to depend on the characteristic wedge size. Near liquid-vapor bulk coexistence, the film mass is observed to diverge as a power law of the chemical potential difference from saturation with an exponent in very good agreement with the value of -2 expected for a linear wedge. This exponent is not affected by the opening angles of the wedges. All these findings are in accordance with a recent scaling theory.

Inhibition of systemic inflammation by central action of the neuropeptide alpha-melanocyte- stimulating hormone

The neuropeptide alpha-melanocyte stimulating hormone (alpha-MSH) reduces fever and acute inflammation in the skin when administered centrally. The aim of the present research was to determine whether central alpha-MSH can also reduce signs of systemic inflammation in mice with endotoxemia. Increases in serum tumor necrosis factor-alpha and nitric oxide, induced by intraperitoneal administration of endotoxin, were modulated by central injection of a small concentration of alpha-MSH. Inducible nitric oxide synthase (iNOS) activity and iNOS mRNA in lungs and liver were likewise modulated by central alpha-MSH. Lung myeloperoxidase activity, a marker of neutrophil infiltration, was increased in endotoxemic mice; the increase was significantly less in lungs of mice treated with central alpha-MSH. Intraperitoneal administration of the small dose of alpha-MSH that was effective centrally did not alter any of the markers of inflammation. In experiments using immunoneutralization of central alpha-MSH, we tested the idea that endogenous peptide induced within the brain during systemic inflammation modulates host responses to endotoxic challenge in peripheral tissues. The data showed that proinflammatory agents induced by endotoxin in the circulation, lungs, and liver were significantly greater after blockade of central alpha-MSH. The results suggest that anti-inflammatory influences of neural origin that are triggered by alpha-MSH could be used to treat systemic inflammation.

Antimicrobial properties of alpha-MSH and related synthetic melanocortins

The natural antimicrobial peptides are ancient host defense effector molecules, present in organisms across the evolutionary spectrum. Several properties of α-melanocyte stimulating hormone (α-MSH) suggested that it could be a natural antimicrobial peptide. α-MSH is a primordial peptide that appeared during the Paleozoic era, long before adaptive immunity developed and, like natural antimicrobial molecules, is produced by barrier epithelia, immunocytes, and within the central nervous system. α-MSH was discovered to have antimicrobial activity against two representative pathogens, Staphylococcus aureus and Candida albicans. The candidacidal influences of α-MSH appeared to be mediated by increases in cell cyclic adenosine monophosphate (cAMP). The cAMP-inducing capacity of α-MSH likely interferes with the yeast's own regulatory mechanisms of this essential signaling pathway. It is remarkable that this mechanism of action in yeast mimics the influences of α-MSH in mammalian cells in which the peptide binds to G-protein-linked melanocortin receptors, activates adenylyl cyclase, and increases cAMP. When considering that most of the natural antimicrobial peptides enhance the local inflammatory reaction, the anti-inflammatory and antipyretic effects of α-MSH confer unique properties to this molecule relative to other natural antimicrobial molecules. Synthetic derivatives, chemically stable and resistant to enzymatic degradation, could form the basis for novel therapies that combine anti-inflammatory and antimicrobial properties.

Incidence of pneumothorax from intercostal nerve block for analgesia in rib fractures

BACKGROUND

The incidence of pneumothorax (PTX) after individual intercostal nerve block (INB) for postoperative pain reportedly varies from 0.073% to 19%.1-3 This study investigated the incidence of PTX after INB for rib fractures.

METHODS

We conducted a retrospective chart review of patients admitted between January 1996 and December 1999 with rib fractures who received INB.

RESULTS

One hundred sixty-one patients received 249 intercostal nerve block procedures (INBPs). An INBP is one session where a set of intercostal nerves are blocked. A total of 1,020 individual intercostal nerves were blocked. There were 14 pneumothoraces. The overall incidence of PTX per patient was 8.7%, with an incidence of PTX per INBP of 5.6%. The incidence of PTX was 1.4% for each individual intercostal nerve blocked.

CONCLUSION

The incidence of PTX per individual intercostal nerve blocked is low. INB is an effective form of analgesia, and for most patients with rib fractures one INBP is sufficient to allow adequate respiratory exercises and discharge from the hospital.

The neuropeptide alpha-MSH in host defense

The presence of the ancient peptide alpha-melanocyte-stimulating hormone (alpha-MSH) in barrier organs such as gut and skin suggests that this potent anti-inflammatory molecule may be a component of the innate host defense. In tests of antimicrobial activities, alpha-MSH and its fragment KPV showed inhibitory influences against the gram-positive bacterium Staphylococcus aureus and the yeast Candida albicans. Anti-tumor necrosis factor and antimicrobial effects of alpha-MSH suggest that the peptide might likewise reduce replication of human immunodeficiency virus (HIV). Treatment with alpha-MSH reduced HIV replication in chronically and acutely infected human monocytes. At the molecular level, alpha-MSH inhibited activation of the transcription factor NF-kappa B known to enhance HIV expression. alpha-MSH that combines antipyretic, anti-inflammatory, and antimicrobial effects could be useful in the treatment of disorders in which infection and inflammation coexist.

alpha-MSH in systemic inflammation. Central and peripheral actions

Until recently, inflammation was believed to arise from events taking place exclusively in the periphery. However, it is now clear that central neurogenic influences can either enhance or modulate peripheral inflammation. Therefore, it should be possible to improve treatment of inflammation by use of antiinflammatory agents that reduce peripheral host responses and inhibit proinflammatory signals in the central nervous system (CNS). One such strategy could be based on alpha-melanocyte stimulating hormone (alpha-MSH). Increases in circulating TNF-alpha and nitric oxide (NO), induced by intraperitoneal administration of endotoxin in mice, were modulated by central injection of a small concentration of alpha-MSH. Inducible nitric oxide synthase (iNOS) activity and iNOS mRNA in lungs and liver were likewise modulated by central alpha-MSH. Increase in lung myeloperoxidase (MPO) activity was significantly less in lungs of mice treated with central alpha-MSH. Proinflammatory agents induced by endotoxin were significantly greater after blockade of central alpha-MSH. The results suggest that antiinflammatory influences of neural origin that are triggered by alpha-MSH could be used to treat systemic inflammation. In addition to its central influences, alpha-MSH has inhibitory effects on peripheral host cells, in which it reduces release of proinflammatory mediators. alpha-MSH reduces chemotaxis of human neutrophils and production of TNF-alpha, neopterin, and NO by monocytes. In research on septic patients, alpha-MSH inhibited release of TNF-alpha, interleukin-1 beta (IL-1 beta), and interleukin-8 (IL-8) in whole blood samples in vitro. Combined central and peripheral influences can be beneficial in treatment of sepsis.

Plasma concentrations of alpha-melanocyte-stimulating hormone are elevated in patients on chronic haemodialysis

BACKGROUND

Clinical and/or laboratory signs of systemic inflammation occur frequently in patients undergoing long-term haemodialysis. It is likely, therefore, that a compensatory release of endogenous anti-inflammatory molecules occurs to limit host reactions. The aim of the present research was to determine if the potent anti-inflammatory peptide alpha-melanocyte-stimulating hormone (alpha-MSH), a pro-opiomelanocortin derivative, is increased in plasma of haemodialysis patients. Because endotoxin and cytokines induce alpha-MSH in vivo and in vitro, we also measured plasma concentrations of endotoxin, interleukin-6 (IL-6), and tumour necrosis factor alpha (TNF-alpha), and the two circulating products of activated monocytes, nitric oxide (NO) and neopterin.

METHODS

Thirty-five chronic haemodialysis patients, 20 patients with chronic renal failure not yet on dialysis, and 35 normal controls were included in the study. In the haemodialysis group, blood samples were obtained before and at the end of a dialysis session. Plasma alpha-MSH was measured using a double antibody radioimmunoassay, and IL-6, TNF-alpha, and neopterin using specific enzyme-linked immunosorbent assays. Plasma nitrites were determined by a colorimetric method, and endotoxin with the quantitative chromogenic LAL (limulus amoebocyte lysate) method.

RESULTS

Mean plasma alpha-MSH was higher in haemodialysis patients than in control subjects, with the peptide concentrations being particularly elevated in dialysed patients with detectable endotoxin. High alpha-MSH concentrations were observed in the pre-dialysis samples, with no substantial change at the end of the dialysis session. Plasma concentrations of IL-6, TNF-alpha, neopterin, and NO were generally elevated in chronic haemodialysis patients and there was a negative correlation between circulating alpha-MSH and IL-6. In patients with renal failure not yet on dialysis, mean plasma alpha-MSH was similar to that of normal subjects.

CONCLUSIONS

alpha-MSH is increased in the circulation of chronic haemodialysis patients and particularly so in case of detectable endotoxaemia. Reduction of renal clearance is unlikely to contribute to the observed rise of the peptide because alpha-MSH concentration is not increased in patients with chronic renal failure who are not yet on dialysis. It is likely that dialysis-associated endotoxaemia, directly and/or through cytokine release, enhances the production of the anti-inflammatory mediator alpha-MSH that limits host reactions.

Postmortem examination of human fetuses: comparison of two-dimensional ultrasound with invasive autopsy

OBJECTIVE

To assess the diagnostic accuracy of postmortem ultrasound performed by operators blinded to prenatal findings and to invasive autopsy results in fetuses at different gestational ages and to investigate the effect of various parameters on its diagnostic success.

METHODS

We performed postmortem two-dimensional ultrasound examination, blinded to clinical details, on 163 fetuses at 13-42 weeks' gestation. Logistic regression analysis was used to investigate the effect of: (i) gestational age at postmortem ultrasound, (ii) presence of maceration and (iii) mode of death, on whether the exam succeeded or failed to reach a diagnosis. In 123 cases in which invasive autopsy was available, the diagnostic accuracy of ultrasound in detecting major organ abnormalities was evaluated, using invasive autopsy as the gold standard.

RESULTS

For the fetal brain, postmortem ultrasound exam was non-diagnostic in significantly more fetuses with maceration (39.5%; 17/43) vs those without maceration (20.0%; 24/120) (P = 0.013). For the fetal thorax, the exam was non-diagnostic in 34.1% (15/44) of fetuses < 20 weeks of gestation and in 10.9% (13/119) of fetuses ≥ 20 weeks (P < 0.001). For the heart and abdominal organs, there was no association between non-diagnostic postmortem ultrasound and the variables tested. For fetuses < 20 weeks, specificity of postmortem ultrasound examination was 83.3% for detection of anomalies of the brain, 68.6% for the thorax and 77.4% for the heart. For fetuses ≥ 20 weeks, sensitivity and specificity were, respectively, 61.9% and 74.2% for detection of anomalies of the brain, 29.5% and 87.0% for the thorax and 65.0% and 83.1% for the heart. For the fetal abdominal organs, sensitivity was 60.7% and specificity 75.8%, and postmortem ultrasound was particularly useful for detection of abnormalities of the kidneys, irrespective of gestational age.

CONCLUSION

Although maceration may lead to failure of postmortem ultrasound examination in some cases, this technique achieves diagnostically acceptable levels of accuracy for fetal brain and abdominal organs, compared with conventional autopsy. It may therefore play a role as a first-line examination before other virtual autopsy techniques are indicated. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.

Ostomy as a risk factor for posttraumatic infection in penetrating colonic injuries: univariate and multivariate analyses

BACKGROUND

Primary repair for penetrating colonic injury is an acceptable practice in uncomplicated injuries, but it is still viewed with trepidation in high risk patients.

METHODS

The records of 350 patients evaluated at an urban Level I trauma center for penetrating colonic injuries over an 8-year period (1989-1997) were reviewed. These included 33 stab and 317 gunshot wounds. Thirty-nine patients died within 48 hours. Of the remaining 311 patients, 78 (25%) developed 152 infections. These infections were classified as traumatic or nosocomial in nature. Traumatic infections (46%) included abdominal abscesses or peritonitis (28), wound infections (30), missile tract infections (8), and fistulas (4), whereas nosocomial infections (54%) included pneumonia (25), bacteremia (25), urinary tract infections (17), miscellaneous (8), empyema (4), and sinusitis (3). Significance for analyses was set at p < 0.05.

RESULTS

Univariate analysis was performed to identify risk factors for the development of infections. The five most significant risk factors, using all infections as an outcome, were as follows: penetrating abdominal trauma index (PATI) greater than 30, presence of an ostomy, multiple transfusions, Injury Severity Score (ISS) of 16 or greater, and Revised Trauma Score less than 7.8. All were highly significant (p < 0.0001). Multivariate analysis with all infections as an outcome revealed that four of the five risk factors had independent effects, with the following significance: PATI greater than 30, ISS of 16 or greater, ostomy, and multiple transfusions. Multivariate analysis for traumatic infections revealed only two of the above to be independent risk factors: presence of an ostomy (p = 0.004) and a PATI greater than 30 (p = 0.039), both of which can be considered local factors. Conversely, multivariate analysis of nosocomial infections revealed independent risk for the two other factors, both of which can be considered systemic factors: multiple transfusions (p = 0.011) and ISS of 16 or greater (p = 0.026).

CONCLUSION

Although most of the above factors are beyond the control of the trauma surgeon, the creation of an ostomy is a clinical decision. The creation of an ostomy in high-risk patients does not protect them from septic complications and, indeed, may independently contribute to local abdominal infections.

Accuracy of 2-Phase Parathyroid CT for the Preoperative Localization of Parathyroid Adenomas in Primary Hyperparathyroidism

BACKGROUND AND PURPOSE

Minimally invasive parathyroidectomy requires accurate preoperative localization of suspected adenomas, and multiphase CT allows adenoma characterization while providing detailed anatomic information. The purpose of this study was to assess the feasibility of a protocol using only arterial and venous phases to localize pathologic glands in patients with primary hyperparathyroidism.

MATERIALS AND METHODS

We identified 278 patients with primary hyperparathyroidism who had undergone 2-phase CT with surgical cure. All scans were read prospectively by board-certified neuroradiologists. A neuroradiology fellow retrospectively reviewed images and reports and classified suspected adenomas on the basis of anatomic location. Accuracy was determined by comparing imaging results with surgical findings. The ability of 2-phase CT to localize adenomas to 1 of 4 neck quadrants and lateralize them to the correct side was assessed. Accuracy of identifying multigland disease was also evaluated.

RESULTS

In patients with single-gland disease, the sensitivity and specificity of 2-phase CT to correctly localize the quadrant were 55.4% and 85.9%, respectively. The sensitivity and specificity of correct lateralization were 78.8% and 67.8%, respectively. The sensitivity and specificity to identify multigland disease were 22.9% and 79.5%, respectively.

CONCLUSIONS

While the 2-phase CT protocol in this study demonstrates lower accuracy compared with reports of other techniques, its lower radiation compared with 3- and 4-phase techniques may make it a feasible alternative for preoperative parathyroid localization. Further prospective studies are needed to identify patients for whom this technique is most suitable.

Crossover effects in the wetting of adsorbed films in linear wedges

We have measured the growth of liquid Ar adsorbed on arrays of linear wedges structured in different ways. In the most regular patterns, a clear crossover from a planarlike to a geometry-dependent growth behavior is observed. This crossover is found to depend on the characteristic wedge size and its position, in the case of a regular pattern, agrees well with theoretical predictions. Near liquid-vapor bulk coexistence, the film mass is observed to diverge as a power law of the chemical potential difference from saturation with an exponent in very good agreement with the value of -2 expected for a linear wedge. This exponent is not affected by the opening angles of the wedges. The form of the next-to-leading order singular term in the asymptotic divergence of the mass has also been investigated. The experimentally determined value of the exponent is consistent with the expected theoretical result of -4/3.

Differences in arterial and mixed venous IL-6 levels: the lungs as a source of cytokine storm in sepsis

BACKGROUND

Several investigators have shown that blood levels of interleukin 6 (IL-6) correlate with the severity of illness in critically ill or injured patients. However, little is known about differential arterial and venous blood levels of the cytokine, especially across the lungs.

METHODS

We measured differences in IL-6 levels in pulmonary and systemic arterial blood and then documented the production or elimination of IL-6 by the lungs in 19 patients with severe illness. Prospective data were obtained from multiple, simultaneous systemic arterial (ART) and mixed venous (MV) blood samples that were drawn for IL-6 analysis from systemic arterial and pulmonary artery catheters in 7 patients awaiting vascular operation and in 12 trauma patients being treated in the intensive care unit.

RESULTS

A lung disorder was present in 5 patients (pneumonia [n = 1], lung trauma [n = 4]) and absent in the remaining 14 patients. The following data were obtained (mean +/- SD) from the highest MV IL-6 levels (pg/mL) in each patient. In patients with a lung disorder (n = 5) compared with those with no disorder (n = 14), ART IL-6 was 9309 +/- 12,521 versus 134 +/- 128 (P =.010), MV IL-6 was 5516 +/- 7420 versus 137 +/- 129 (P =.011), the absolute difference was 3793 +/- 5271 versus -3 +/- 15 (P =.011), and the percentage difference was 37.4% +/- 29.8% versus 1.5% +/- 12.3% (P =.001). The ART and MV IL-6 levels tended to be much higher in the 5 patients with pneumonia (n = 1) and lung injuries (n = 4) than in the patients without apparent pulmonary problems. In addition, the patients with a primary lung disorder demonstrated a net increase in IL-6 levels across the lungs, whereas there was no increase, but rather, a net reduction of IL-6 levels across the lungs in patients without a lung disorder.

CONCLUSIONS

The lung appears to be a major producer of IL-6 in patients with an inflammatory lung process. There is a 39% increase in the level of IL-6 as it passes through inflamed lung, producing a marked difference in ART and MV IL-6 levels. Normal lung demonstrated little effect on either ART or MV IL-6 levels.

Diffuse Placental Chorioangiomatosis and Fetal Hydrops

A highly unusual case of a pregnancy complicated by diffuse placental chorioangiomatosis that resulted in a live-birth and short-term fetal survival is reported. The potential for antenatal diagnosis and intrauterine treatment to optimise fetal outcome is discussed.

Rapid development of vitamin K deficiency in an adolescent boy receiving total parenteral nutrition following bone marrow transplantation

In this case report the development of a vitamin K deficiency in a neutropenic adolescent receiving parenteral nutrition following bone marrow transplantation is described. The parenteral nutrition solution did not provide vitamin K and the patient had been receiving oral antibiotics prior to and during use of the intravenous feeding. Oral intake was minimal. Standard adult oral and intravenous multivitamin preparations for use in individuals older than 11 years do not routinely contain this vitamin. The function of vitamin K and causes for development of a deficiency are reviewed. Recommended intakes and guidelines for supplementation are also discussed.

Evaluation of academic and community surgery clerkships at a Midwestern medical school

BACKGROUND

The equivalency of surgical clerkship experience between academic and community sites is an issue that is assessed with difficulty. We examined the objective performance of 222 medical students after completion of the 8-week surgical clerkship. Six different consecutive semesters were analyzed. There were two objective examinations reviewed, the National Board of Medical Examiners' subject examination and the surgical subportion of the Objective Structured Clinical Examination (OSCE) given at the end of the third year.

METHODS

Medical students were classified into three separate groups based on the site of their surgical clerkship. The medical students were in either academic (100), community (79), or combined (academic and community) (43) locations. Medical student performance on the subject examination and OSCE was examined after completion of the general surgical clerkship. Single-factor analysis of variance testing was done to compare each of the three groups with respect to subject examination test score, or OSCE score. Significance was defined as P < 0.05.

RESULTS

The combined group scored highest on the subject examination (73.6%). The community group scored highest on the OSCE (80.7%). However, no statistical significance exists between the three groups with regard to subject examination (P = NS) or OSCE (P= NS). Subject examination scores did not correlate with OSCE scores (r = 0.095). Objective measurements of surgical subject examination and OSCE were not statistically different between academic, community, and academic and community surgical clerkship participants.

CONCLUSIONS

No statistically significant differences exist between the three groups with regards to OSCE failure rates, but the small amount of failures may have caused Type 2 error. Surgical clinical skills as tested by an OSCE and surgical knowledge as tested by a subject examination are equally attained by an academic or community surgical clerkship.

Assay for valproic acid and its E-delta2 metabolite in rat plasma by capillary gas chromatography without prior derivatization

A new and improved gas chromatographic assay method for valproic acid and a metabolite, E-delta2 valproic acid, in rat plasma has been developed. The assay has sufficient sensitivity to measure free levels of the parent drug and metabolite. By employing a Stabilwax-DA capillary column, symmetrical chromatographic peaks were obtained without the need for prior derivatization. Standard curves for valproic acid were linear from 0.1 to 640 microg/ml. Standard curves for the metabolite were linear from 0.1 to 556 microg/ml.

Screening for atrial fibrillation in the community: A multicenter validation trial

BACKGROUND

Atrial fibrillation (AF) is an important public health problem. This arrhythmia is common and associated with a high risk of stroke. Further, appropriate interventions in AF can reduce the risk of stroke by approximately 68%. Population studies show that a large group of patients have intermittent or chronic AF that remains unrecognized. If a simple screening test for this arrhythmia could be developed and validated, application of the technique across populations might identify AF patients for early treatment, potentially reducing the incidence of stroke. In this study, we sought to determine whether individuals taken from the general community could be taught to find and classify the pulse of another as very irregular, implying AF, or regular, implying normal sinus rhythm (NSR). The aim was to establish that pulse examination for potential AF could be performed by individuals with sufficient sensitivity and specificity to be effectively used as a screening procedure for this medically important arrhythmia.

METHODS

We enrolled 178 subjects selected from the general community from four centers. Subjects received standardized education on the medical importance of AF and its signature, a very irregular pulse. A technique for palpating and characterizing the rhythm of the radial pulse was also taught. Without further coaching, subjects were then asked to find their pulse and then to find and classify the pulse of two models randomly presented who may or may not have had AF.

RESULTS

Of the 178 subjects tested, 92% were able to find their own pulse; 17 (9.6%) were unable to find the pulse of one or both patient models and were, therefore, excluded from the study. Of the remaining 161 subjects, 76% (122 of 161) correctly identified the pulse in an AF model, and 86% (139 of 161) correctly identified the pulse in an NSR model. Results did not statistically differ as a function of age, educational status, or location.

DISCUSSION

This multicenter trial established that given minimal standardized instructions, subjects from the general community can reliably and consistently find both their pulse as well as the pulse of another and to differentiate a regular pulse from a very irregular pulse. If similar educational programs were widely applied across large populations, periodic screening for AF might lead to earlier diagnosis and appropriate treatment for patients who have this major risk factor for stroke. These screening programs should be focused on the population over the age of 55 where the risk of stroke in AF increases with each decade.