Population-based cohort study of variation in the use of emergency cholecystectomy for benign gallbladder diseases

Background

The aims of this prospective population-based cohort study were to identify the patient and hospital characteristics associated with emergency cholecystectomy, and the influences of these in determining variations between hospitals.

Methods

Data were collected for consecutive patients undergoing cholecystectomy in acute UK and Irish hospitals between 1 March and 1 May 2014. Potential explanatory variables influencing the performance of emergency cholecystectomy were analysed by means of multilevel, multivariable logistic regression modelling using a two-level hierarchical structure with patients (level 1) nested within hospitals (level 2).

Results

Data were collected on 4744 cholecystectomies from 165 hospitals. Increasing age, lower ASA fitness grade, biliary colic, the need for further imaging (magnetic retrograde cholangiopancreatography), endoscopic interventions (endoscopic retrograde cholangiopancreatography) and admission to a non-biliary centre significantly reduced the likelihood of an emergency cholecystectomy being performed. The multilevel model was used to calculate the probability of receiving an emergency cholecystectomy for a woman aged 40 years or over with an ASA grade of I or II and a BMI of at least 25·0 kg/m2, who presented with acute cholecystitis with an ultrasound scan showing a thick-walled gallbladder and a normal common bile duct. The mean predicted probability of receiving an emergency cholecystectomy was 0·52 (95 per cent c.i. 0·45 to 0·57). The predicted probabilities ranged from 0·02 to 0·95 across the 165 hospitals, demonstrating significant variation between hospitals.

Conclusion

Patients with similar characteristics presenting to different hospitals with acute gallbladder pathology do not receive comparable care.

A phase II study of the HDAC inhibitor SB939 in patients with castration resistant prostate cancer: NCIC clinical trials group study IND195

BACKGROUND

SB939 is a potent oral inhibitor of class 1, 2, and 4 histone deacetylases (HDACs). These three HDAC classes are highly expressed in castration resistant prostate cancer (CRPC) and associated with poor clinical outcomes. We designed a phase II study of SB939 in men with metastatic CRPC.

METHODS

Patients received SB939 60 mg on alternate days three times per week for 3 weeks on a 4-week cycle. Primary endpoints were PSA response rate (RR) and progression-free survival (PFS). Secondary endpoints included objective response rate and duration; overall survival; circulating tumor cell (CTC) enumeration and safety. Exploratory correlative studies of the TMPRSS2-ERG fusion and PTEN biomarkers were also performed.

RESULTS

Thirty-two patients were enrolled of whom 88 % had received no prior chemotherapy. The median number of SB939 cycles administered was three (range 1-8). Adverse events were generally grade 1-2, with five pts experiencing one or more grade three event. One patient died due to myocardial infarction. A confirmed PSA response was noted in two pts (6 %), lasting 3.0 and 21.6 months. In patients with measurable disease there were no objective responses. Six patients had stable disease lasting 1.7 to 8.0 months. CTC response (from ≥5 at baseline to <5 at 6 or 12 weeks) occurred in 9/14 evaluable patients (64 %).

CONCLUSION

Although SB939 was tolerable at the dose/schedule given, and showed declines in CTC in the majority of evaluable patients, it did not show sufficient activity based on PSA RR to warrant further study as a single agent in unselected patients with CRPC.

Cells deficient in the base excision repair protein, DNA polymerase beta, are hypersensitive to oxaliplatin chemotherapy

A significant proportion of human cancers overexpress DNA polymerase beta (Pol beta), the major DNA polymerase involved in base excision repair. The underlying mechanism and biological consequences of overexpression of this protein are unknown. We examined whether Pol beta, expressed at levels found in tumor cells, is involved in the repair of DNA damage induced by oxaliplatin treatment and whether the expression status of this protein alters the sensitivity of cells to oxaliplatin. DNA damage induced by oxaliplatin treatment of HCT116 and HT29 colon cancer cells was observed to be associated with the stabilization of Pol beta protein on chromatin. In comparison with HCT116 colon cancer cells, isogenic oxaliplatin-resistant (HCT-OR) cells were found to have higher constitutive levels of Pol beta protein, faster in vitro repair of a DNA substrate containing a single nucleotide gap and faster repair of 1,2-GG oxaliplatin adduct levels in cells. In HCT-OR cells, small interfering RNA knockdown of Pol beta delayed the repair of oxaliplatin-induced DNA damage. In a different model system, Pol beta-deficient fibroblasts were less able to repair 1,2-GG oxaliplatin adducts and were hypersensitive to oxaliplatin treatment compared with isogenic Pol beta-expressing cells. Consistent with previous studies, Pol beta-deficient mouse fibroblasts were not hypersensitive to cisplatin treatment. These data provide the first link between oxaliplatin sensitivity and DNA repair involving Pol beta. They demonstrate that Pol beta modulates the sensitivity of cells to oxaliplatin treatment.

Fast response temperature measurement and highly reproducible heating methods for 96-well plates

Hyperthermia, the procedure of exposing cells to a temperature between 42° and 49°C, has been shown to be a promising approach for cancer treatment. To understand the underlying mechanisms of hyperthermic killing of cancer cells, it is critical to have an accurate temperature measurement technique and a heating method with high reproducibility. To this end, we have developed a method using fine thermocouples with fast response time to measure the temperatures in multiple wells of a 96-well plate. The accuracy of temperature measurement was ±0.2°C. Such a capability allows a complete record of the time and temperature of the treatment procedure and helps define an accurate thermal dose. We have also compared several methods for heating 96-well plates and found that use of copper blocks in contact with the lower surface of the 96-well plate in an incubator provides a highly reproducible heating method. The common method of using water bath to heat cells in vitro resulted in a decrease of cell viability even at the control temperature of 37°C and a decrease in the reproducibility of certain biological assays. In summary, using these improved techniques, proposed thermal dose can be defined more precisely, and highly reproducible heating in vitro can be achieved.

Static and quasi-static calibration of a bio-MEMS device

A bio-MEMS device that has been designed to stimulate cells by oscillatory actuation in the vertical direction has been calibrated. The displacement of this device was determined experimentally by a laser interferometer when actuated by a static voltage, and by an atomic force microsope when actuated quasi-statically at 0.1 Hz. Both experimental calibrations were compared to a simple model.

Dramatic response of teratoma-associated non--germ-cell cancer with all-trans retinoic acid in a patient with nonseminomatous germ cell tumor

A patient with nonseminomatous germ cell cancer, treated with standard chemotherapy, subsequently developed a pathologically confirmed metastatic undifferentiated adenocarcinoma (non-germ-cell elements) arising from residual teratoma. Disease was present in both lobes of the liver and was deemed unresectable at the time of presentation. The patient was treated on a National Cancer Institute-sponsored institutional protocol with all-trans retinoic acid. After 60 days of oral therapy at a dose of 150 mg/m2/d (50 mg/m2 three times daily), the patient was found to have complete radiologic resolution of his hepatic metastases. He subsequently underwent surgery and his complete response was pathologically confirmed.

Long-term follow-up of a phase III study of three versus four cycles of bleomycin, etoposide, and cisplatin in favorable-prognosis germ-cell tumors: the Indian University experience

PURPOSE

In a previously reported randomized Southeastern Cancer Study Group (SECSG) trial, three cycles of chemotherapy were found to be equivalent to four cycles in patients with favorable-prognosis germ-cell cancer. We have conducted a follow-up analysis of patients treated at Indiana University (Indianapolis, IN) to compare long-term survival between the two groups and to examine factors associated with survival.

PATIENTS AND METHODS

Sixty-nine patients with minimal-stage and 49 patients with moderate-stage disseminated germ-cell tumors were randomized to either three or four courses of bleomycin, etoposide, and cisplatin (BEP) administered every 3 weeks. Median follow-up time is 10.1 years (range, 7 months to 12.6 years). Ninety-two percent of patients have an actual follow-up time of > 5 years, and 97.5% of patients have an actual follow-up time of > 3 years.

RESULTS

Survival analysis shows no significant difference between the two treatment groups in terms of overall (P = .80) or disease-free (P = .93) survival. Several clinical variables were examined by univariate analysis; only serum human chorionic gonadotropin (HCG) had an impact on survival. There were two disease-related deaths in 104 patients with HCG < or = 1,000 mIU/mL and five disease-related deaths in 14 patients with HCG greater than 1,000 mIU/mL (P < .001). Ninety-eight percent (95% CI, 95.2 to 100) of patients with favorable prognosis germ-cell tumor with an initial HCG of < or = 1,000 mIU/mL are alive without evidence of disease at 5+ years.

CONCLUSION

With long-term follow-up, there is no statistically significant difference in survival between three or four cycles of BEP chemotherapy in patients with favorable prognosis germ-cell carcinoma. Serum HCG elevation of greater than 1,000 mIU/mL is a significant predictor of poor outcome in patients with otherwise good-risk disease.

Elements for a report card: one institution's experience moving from theory to trial

The emerging computerized patient record, the movement toward a unified nursing language, and increasing accountability to the public for clinical outcomes are converging forces that require a coherent plan if nursing is to evaluate outcomes. The article describes a nursing service and school of nursing's approach and beginning experiences in identifying concepts and indicators that are useful to clinicians. These concepts and indicators have the potential to be embedded in a concurrent information system that would feed a data repository used retrospectively by clinicians and researchers. The article also discusses results to date and lessons learned.

Early effect of carotid endarterectomy on arterial blood pressure measured with an ambulatory monitor

BACKGROUND

Carotid artery disease and hypertension are associated, and carotid endarterectomy is often followed by acute changes in blood pressure. As the carotid sinus is responsible for short-term blood pressure control, occlusive carotid disease may contribute to the mechanism of preoperative hypertension.

METHODS

Ten patients undergoing carotid endarterectomy and eight having a peripheral bypass procedure were studied 2 weeks before and 2 weeks after operation, using home ambulatory blood pressure measurement.

RESULTS

A significant fall in both mean systolic (-14.4 mmHg) and mean diastolic (-12.7 mmHg) pressure was observed after carotid endarterectomy (P < 0.006), whereas no change was seen in controls.

CONCLUSION

These results suggest that there is an increase in carotid sinus activity in patients following carotid endarterectomy and supports the hypothesis that carotid sinus dysfunction contributes to hypertension in patients with carotid artery disease.

Activation of coagulation and platelets is affected by the hydrophobicity of artificial surfaces

Clot formation is a limiting factor in the use of biomaterials. We investigated the effect of surface hydrophobicity on haemostatic activation in vitro, using five polyetherurethanes of varying surface hydrophobicity (C94, C74, C54 and C34), C94 the most, and C34, the least hydrophobic, and compared them with a commercial standard pellethane. Sterilised sacks were filled with heparinised blood, rotated at 37 degrees C for 24 h and sequential samples collected into 0.103 M sodium citrate. Thrombin generation measured by thrombin-antithrombin III complexes showed a difference between the polymers at 3 h through to 6 h (P < 0.05), C94 showing the least activation and C34 the most. Factor XIIa and D-dimer levels increased between 12 (P < 0.05) and 24 h (P < 0.01) for all polyetherurethanes. The ratio of soft:hard segments (which determine hydrophobicity) of the polyetherurethanes showed a direct relationship with the degree of activation of coagulation and fibrinolysis. There was no significant increase in monocyte tissue factor expression at 5 and 105 min. Platelet function as measured by whole blood platelet aggregation showed a reduction with pellethane and C94 after 1 h using collagen, with no changes for C34, Altering surface hydrophobicity has diverse effects on haemostatic pathways, with the most hydrophobic surfaces causing least activation of coagulation but most activation of platelets.

The utility of a single sputum specimen in the diagnosis of tuberculosis. Comparison between HIV-infected and non-HIV-infected patients

STUDY OBJECTIVES

(1) To assess the utility of a single sputum specimen in the evaluation of HIV-infected patients who are suspected of having tuberculosis (TB). (2) To identify radiographic findings that discriminate between HIV-infected patients with TB and those with pneumonia of other causes.

DESIGN

Retrospective cohort analysis.

PATIENTS

All patients evaluated at Harborview Medical Center, Seattle, between January 1986 and July 1994 in whom culture of respiratory secretions grew Mycobacterium tuberculosis or Mycobacterium avium-complex. Patients who were coinfected with HIV formed the primary study group. Their chest radiographs were then compared with those of a matched group of patients with pneumonia of other causes.

MEASUREMENTS AND RESULTS

We identified 164 patients with TB, 20 of whom were HIV infected. The initial sputum specimen grew M tuberculosis in all HIV-infected patients and 99% of non-HIV-infected patients. Seventy percent of HIV-infected and 71% of non-HIV-infected patients had at least one positive smear. Most of these patients tested positive on their initial smear, and no significant difference was found between HIV-positive and HIV-negative patients (79% and 90%, respectively [p = 0.34]). The addition of a second sputum smear identified all HIV-infected patients and all but one in non-HIV-infected patients who were ultimately determined to be smear positive. A total of 27 HIV-infected patients had a positive acid-fast bacilli sputum smear during the study period, 14 of which were attributable to TB (specificity = 52%). The only radiographic findings that discriminated between HIV-infected patients with TB and those with pneumonia of other causes were the presence of cavitation or a miliary pattern (p = 0.014).

CONCLUSIONS

A single sputum specimen was sufficient to establish the diagnosis in all HIV-infected patients with pulmonary TB. A single negative sputum smear made the diagnosis of TB significantly less likely. However, a minimum of two smears were necessary to achieve an acceptable early diagnostic yield. The presenting chest radiograph failed to discriminate between HIV-infected patients with TB and pneumonia of other causes in most cases.

Effect of insulin on renal sodium handling in hypertensive rats

Spontaneously hypertensive rats have reduced peripheral insulin sensitivity. To determine whether hypertensive rats demonstrate reduced response to the antinatriuretic effect of insulin, urinary sodium excretion was determined in hypertensive and normotensive rats (n = 7 per group) before and during euglycemic insulin administration at two infusion rates (21 milliunits/kg load and 4 milliunits/kg/min or 85 milliunits/kg load and 8 milliunits/kg/min). Hypertensive and normotensive time controls received the vehicle for insulin administration. Mean arterial pressure was greater (p less than 0.05) and inulin clearance was less (p less than 0.05) in hypertensive than normotensive rats before insulin infusion. Baseline fractional sodium excretion was not different between groups. Low dose insulin infusion reduced (p less than 0.05) fractional sodium excretion from 0.81 +/- 0.43% to 0.31 +/- 0.07% in hypertensive rats and from 1.05 +/- 0.37% to 0.47 +/- 0.18% in normotensive rats. High dose insulin infusion reduced (p less than 0.05) fractional sodium excretion from 0.67 +/- 0.22% to 0.21 +/- 0.08% in hypertensive rats and from 0.81 +/- 0.15% to 0.30 +/- 0.09% in normotensive rats. Sodium excretion was unchanged in time controls. The reduction in sodium excretion was similar in both rat groups during low dose and high dose insulin infusions. Mean arterial pressure and inulin clearance were unchanged from baseline values during insulin infusion in all rat groups. Glucose requirement to maintain euglycemia was greater (p less than 0.05) in normotensive than hypertensive rats at both insulin infusion rates. Thus, while hypertensive rats have reduced sensitivity to the hypoglycemic effects of insulin, the antinatriuretic response to insulin is not different from that of normotensive rats.(ABSTRACT TRUNCATED AT 250 WORDS)

A theoretical approach to nursing assessment

Nurses use theory to sharpen their observations and to facilitate their understanding of the human responses to which they direct their interventions. An assessment tool, derived from the nursing theory 'modelling and role-modelling', was developed by nurses at the University of Michigan Hospitals. This tool appears to elicit the data necessary to assess and diagnose the health status of clients. This article describes the assessment tool, why it was developed, the objectives in utilization of the tool and suggestions for implementation.

Neuronal response of the hippocampal formation to injury: blood flow, glucose metabolism, and protein synthesis

The reaction of the hippocampal formation to entorhinal lesions was studied from the viewpoints of cerebral blood flow ([123I]isopropyl-iodoamphetamine[IMP])-glucose utilization ([14C]2-deoxyglucose), and protein synthesis ([14C]leucine), using single- and double-label autoradiography. Our study showed (i) decreased glucose utilization in the inner part, and increased glucose utilization in the outer part of the molecular layer of the dentate gyrus, starting 3 days after the lesion; (ii) increased uptake of [123I]IMP around the lesion from 1 to 3 days postlesion; and (iii) starting 3 days after the lesion, marked decrease in [14C]leucine incorporation into proteins and cell loss in the dorsal CA1 and dorsal subiculum in about one-half of the rats. These changes were present only in animals with lesions which invaded the ventral hippocampal formation in which axons of CA1 cells travel. By contrast, transsection of the 3rd and 4th cranial nerves resulted, 3 to 9 days after injury, in a striking increase in protein synthesis in the oculomotor and trochlear nuclei. These results raise the possibility that in some neurons the failure of central regeneration may result from the cell's inability to increase its rate of protein synthesis in response to axonal injury.

Hyperbolic geometry as an alternative to perspective for constructing drawings of visual space

It is demonstrated by the use of drawings: (i) that two-point perspective drawings based on projective geometry possess systematic distortions, and (ii) that these distortions can be eliminated in drawings based on hyperbolic geometry.

Description of a new visual illusion: a drawing of a four-dimensional cube

The visual responses evoked by an oblique projection of a four-dimensional cube are discussed and attention is drawn to the visual complexity and illusions evoked by this figure.