Increased risk of postoperative complications with retromuscular mesh placement in emergency incisional hernia repair: A nationwide register-based cohort study

INTRODUCTION

Incisional hernia is common after abdominal surgery. Watchful waiting carries the risk of incarceration and a need for emergency intervention. The aim of this study was to examine the risk of postoperative complications after emergency versus elective incisional hernia repair.

METHODS

Patients above 18 years of age undergoing open incisional hernia repair in Denmark in 2017-2018 were identified in the Danish Ventral Hernia Database. Patients were grouped according to elective or emergency hernia repair. The primary outcome was postoperative complications requiring operative intervention within 90 days, and the secondary outcome was postoperative length of stay.

RESULTS

We included 1050 patients, of whom 882 were admitted for elective and 168 for emergency operation. Patients undergoing emergency repair were older (64.7 years vs 59.2 years, p < 0.001), more often smokers (25.8% vs 13.6%, p = 0.003), and more often had a Charlson comorbidity score ⩾2 (26.8% vs 19.2%, p = 0.005) compared to patients undergoing elective repair. In a multivariate regression analysis, emergency compared to elective operation (OR = 2.71, 95% CI = 1.4-5.25, p = 0.003) and retromuscular compared to onlay mesh placement (OR = 2.14, 95% CI = 1.08-4.24, p = 0.013) were factors significantly associated with increased risk of postoperative complications. In a subgroup analysis including only emergency repairs, risk of complications after retromuscular mesh placement was even higher (OR = 10.12, 95% CI = 1.81-56.68, p = 0.008).

CONCLUSION

Emergency incisional hernia repair was associated with increased risk of postoperative complications and this risk was accentuated with retromuscular mesh placement. The use of retromuscular mesh in the emergency setting should be avoided, and the abdominal wall could either be closed by sutures or additional onlay mesh.

Anaesthesia practices for endovascular therapy of acute ischaemic stroke: a Nordic survey

BACKGROUND

The optimal method of anaesthesia for endovascular therapy (EVT) in acute ischaemic stroke (AIS) has not been identified. Nordic departments of anaesthesiology may handle EVT cases for AIS differently. The aim of this survey was to describe the current practice patterns of Nordic anaesthesia departments in anaesthetic management of EVT in AIS.

METHODS

A survey consisting of 13 questions was sent to one qualified individual at all Nordic departments of anaesthesiology who manage anaesthesia for EVT interventions. The individual completed the questionnaire on behalf of their department.

RESULTS

Response rate was 100%. The majority of departments (84%) managed all EVT cases at their respective centres. Most departments have institutional guidelines on anaesthetic management (84%) including blood pressure management (63%) and were able to provide a 24-h immediate response to an EVT request (63%). Conscious sedation was favoured by 68% of the departments using a variety of sedation protocols. Propofol and remifentanil was preferred for GA (58%). Emergent conversion to GA due to uncontrolled patient movements or loss of airway was experienced by 82% and 35% of the departments, respectively. Majority of the departments (89%) responded that non-specialist anaesthetists occasionally handle EVT cases.

CONCLUSIONS

This survey indicates that the majority of Nordic anaesthesia departments who manage anaesthesia for EVT are able to provide immediate 24-h response to an EVT request. Most of these departments have institutional guidelines for EVT anaesthesia and haemodynamic management. Conscious sedation appears to be the preferred method of anaesthetic care.

Ultrasonically Guided Percutaneous Treatment of Liver Abscesses

Twenty-two patients with liver abscesses demonstrated by ultrasonography (US) were treated over a nine-year period. The diagnosis was in all cases verified by puncture. The patients were treated by US-guided puncture or catheter drainage. Seventeen patients (77%) were cured without surgical drainage. Four patients were cured after subsequent surgical intervention. One patient died later of pancreatic carcinoma. There were no complications from the US-guided therapy. For the treatment of liver abscesses we recommend US-guided drainage as the first choice. Close collaboration between surgeon and radiologist is mandatory since some of these patients still need surgical treatment.

Economic and environmental optimization of waste treatment

This article presents the new systems engineering optimization model, OptiWaste, which incorporates a life cycle assessment (LCA) methodology and captures important characteristics of waste management systems. As part of the optimization, the model identifies the most attractive waste management options. The model renders it possible to apply different optimization objectives such as minimizing costs or greenhouse gas emissions or to prioritize several objectives given different weights. A simple illustrative case is analysed, covering alternative treatments of one tonne of residual household waste: incineration of the full amount or sorting out organic waste for biogas production for either combined heat and power generation or as fuel in vehicles. The case study illustrates that the optimal solution depends on the objective and assumptions regarding the background system--illustrated with different assumptions regarding displaced electricity production. The article shows that it is feasible to combine LCA methodology with optimization. Furthermore, it highlights the need for including the integrated waste and energy system into the model.

Challenges when performing economic optimization of waste treatment: a review

Strategic and operational decisions in waste management, in particular with respect to investments in new treatment facilities, are needed due to a number of factors, including continuously increasing amounts of waste, political demands for efficient utilization of waste resources, and the decommissioning of existing waste treatment facilities. Optimization models can assist in ensuring that these investment strategies are economically feasible. Various economic optimization models for waste treatment have been developed which focus on different parameters. Models focusing on transport are one example, but models focusing on energy production have also been developed, as well as models which take into account a plant's economies of scale, environmental impact, material recovery and social costs. Finally, models combining different criteria for the selection of waste treatment methods in multi-criteria analysis have been developed. A thorough updated review of the existing models is presented, and the main challenges and crucial parameters that need to be taken into account when assessing the economic performance of waste treatment alternatives are identified. The review article will assist both policy-makers and model-developers involved in assessing the economic performance of waste treatment alternatives.

Regional cerebral glucose metabolism during sevoflurane anaesthesia in healthy subjects studied with positron emission tomography

BACKGROUND

The precise mechanism by which sevoflurane exerts its effects in the human brain remains unknown. In the present study, we quantified the effects of sevoflurane on regional cerebral glucose metabolism (rGMR) in the human brain measured with positron emission tomography.

METHODS

Eight volunteers underwent two dynamic 18F-fluorodeoxyglucose positron emission tomography (PET) scans. One scan assessed conscious-baseline metabolism and the other scan assessed metabolism during 1 minimum alveolar concentration (MAC) sevoflurane anaesthesia. Cardiovascular and respiratory parameters were monitored and bispectral index responses were registered. Statistical parametric maps and conventional regions of interest analysis were used to determine rGMR differences.

RESULTS

All subjects were unconsciousness at 1.0 MAC sevoflurane. Cardiovascular and respiratory parameters were constant over time. In the awake state, rGMR ranged from 0.24 to 0.35 mumol/g/min in the selected regions. Compared with the conscious state, total GMR decreased 56% in sevoflurane anaesthesia. In white and grey matter, GMR was averaged 42% and 58% of normal, respectively. Sevoflurane reduced the absolute rGMR in all selected areas by 48-71% of the baseline (P< or = 0.01), with the most significant reductions in the lingual gyrus (71%), occipital lobe in general (68%) and thalamus (63%). No increases in rGMR were observed.

CONCLUSIONS

Sevoflurane caused a global whole-brain metabolic reduction of GMR in all regions of the human brain, with the most marked metabolic suppression in the lingual gyrus, thalamus and occipital lobe.

Regional cerebral blood flow responses to hyperventilation during sevoflurane anaesthesia studied with PET

BACKGROUND

Arterial carbon dioxide tension (PaCO(2)) is an important factor controlling cerebral blood flow (CBF) in neurosurgical patients. It is still unclear whether the hypocapnia-induced decrease in CBF is a general effect on the brain or rather linked to specific brain regions. We evaluated the effects of hyperventilation on regional cerebral blood flow (rCBF) in healthy volunteers during sevoflurane anaesthesia measured with positron emission tomography (PET).

METHODS

Eight human volunteers were anaesthetized with sevoflurane 1 MAC, while exposed to hyperventilation. During 1 MAC sevoflurane at normocapnia and 1 MAC sevoflurane at hypocapnia, one H(2)(15)O scan was performed. Statistical parametric maps and conventional regions of interest analysis were used for estimating rCBF differences.

RESULTS

Cardiovascular parameters were maintained constant over time. During hyperventilation, the mean PaCO(2) was decreased from 5.5 + or - 0.7 to 3.8 + or - 0.9 kPa. Total CBF decreased during the hypocapnic state by 44%. PET revealed wide variations in CBF between regions. The greatest values of vascular responses during hypocapnia were observed in the thalamus, medial occipitotemporal gyrus, cerebellum, precuneus, putamen and insula regions. The lowest values were observed in the superior parietal lobe, middle and inferior frontal gyrus, middle and inferior temporal gyrus and precentral gyrus. No increases in rCBF were observed.

CONCLUSIONS

This study reports highly localized and specific changes in rCBF during hyperventilation in sevoflurane anaesthesia, with the most pronounced decreases in the sub cortical grey matter. Such regional heterogeneity of the cerebral vascular response should be considered in the assessment of cerebral perfusion reserve during hypocapnia.

Paradoxical Relationship of Chromosomal Instability with Breast Cancer Outcome: Identification of a Good Prognostic ER Negative/HER2 Negative Breast Cancer Cohort with Extreme Chromosomal Instability

Chromosomal Instability (CIN) is widely held to be associated with poor prognosis in solid tumours, including breast cancer, that may be related to enhanced clonal evolutionary capacity and the rapid acquisition of multi-drug resistance. Paradoxically, CIN is also associated with tumour suppression in animal models that may result from excessive genomic instability leading to autonomous cell lethality, a phenomenon analogous to "mutational meltdown" in model systems.We addressed whether such a phenomenon could be identified in breast cancer through a meta-analysis of CIN frequency in 1850 breast cancer patients. We assessed the distribution of CIN across breast cancer subtypes and its relationship with clinical outcome and prognosis using a surrogate of CIN, the CIN70 expression signature that correlates robustly with CIN in breast cancers quantified by DNA image cytometry. Increasing degrees of CIN predicted for poor outcome in multivariate analysis of 1850 patients and occurred more frequently in younger patients. Furthermore, CIN was more common in higher risk disease subtypes, including basal-like breast cancer, consistent with this pattern of genomic instability being a major determinant of breast cancer outcome.However, in agreement with previous evidence documenting a role for CIN in mediating cell lethality and tumour suppression in animal models, we demonstrate that a subset of tumours with extremes of CIN, that occur predominantly within the ER negative and HER2 negative subgroup, are associated with unexpected good prognosis in untreated breast cancer patients.We define a threshold of CIN beyond which clinical outcome improves and the relationship between CIN and proliferation is uncoupled. This evidence defines a paradoxical role for CIN in limiting tumour cell viability in vivo and suggests therapeutic strategies to tilt the balance toward CIN-mediated lethality in high-risk breast cancer subtypes in order to improve patient outcome.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 3030.

Regulators of Mitotic Transition Determine Paclitaxel Resistance In Vitro and Predict Poor Prognosis in Breast Cancer In Vivo

We have previously identified 25 kinases that regulate sensitivity to the microtubule-stabilising drug, paclitaxel (Swanton et al., 2007). Silencing these kinases by small-interfering RNA (siRNA), results in resistance to paclitaxel-induced cytotoxicity and dramatic alterations in DNA ploidy, multinucleation and centrosome amplification independent of drug treatment. These data suggest that the molecular pathways that maintain chromosome stability and mitotic fidelity are required for paclitaxel sensitivity. To further address this, we have investigated the function of the 25 kinases in mitosis, using a combination of fixed and live-cell microscopy. Several of these genes regulate mitotic progression and the formation of a bipolar mitotic spindle, and upon depletion, lead to increased rates of chromosome missegregation during anaphase. This supports the hypothesis that mechanisms of chromosomal instability that are common in cancer cells, predispose to paclitaxel resistance. In order to assess the in vivo relevance of these kinases we examined whether lower expression held prognostic power across several breast cancer datasets. Notably low expression of MAST3, CAMK1 and SKAP1 correlates with poor prognosis in breast cancer in vivo (P&lt;0.05). Interestingly, MAST3 and CAMK1 have strikingly similar mitotic phenotypes after silencing; cells arrest in early mitosis and show an increased frequency of anaphase errors that may contribute to chromosomal instability. In summary, we have identified novel regulators of mitotic transition that may be important for maintaining chromosomal stability. These kinases influence taxane sensitivity in vitro and hold prognostic power in breast cancer patients in vivo.ReferencesSwanton, C., Marani, M., Pardo, O., Warne, P.H., Kelly, G., Sahai, E., Elustondo, F., Chang, J., Temple, J., Ahmed, A.A., et al. (2007). Regulators of mitotic arrest and ceramide metabolism are determinants of sensitivity to paclitaxel and other chemotherapeutic drugs. Cancer Cell 11, 498-512

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 2151.

A Functional Metagene Incorporating TTK Protein Kinase, Aurora Kinase B and Glucosylceramide Synthase Predicts Response to Treatment in Primary Breast Cancer

Deriving robust gene expression signatures from microarray data that predict response to a given chemotherapeutic treatment has been hindered due to over-fitting of data. To overcome this problem, we have taken the approach to combine genes known to be functionally involved in drug response into a “functional metagene” to predict pathological complete response to treatment in primary breast cancer.Using published functional genomics RNA interference data and microarray datasets we identified 46 genes that alter paclitaxel sensitivity in laboratory cell line models and are also measured by the U133A microarray platform. In order to filter genes into a functional metagene with a putative role in taxane response in breast cancer, we addressed whether the expression of these genes was predictive of pathological complete response in a primary breast cancer clinical dataset treated with taxane, 5-fluorouracil, adriamycin and cyclophosphamide (TFAC). We identified two genes, TTK protein kinase and aurora kinase B, which showed increased expression in responders, and one gene, glucosylceramide synthase, which showed decreased expression in responders (P &lt; 0.001, AUC &gt; 0.7, all 3 genes). We then combined these three genes into a functional metagene which we tested in a validation clinical trial cohort that had also received TFAC. We found that the functional metagene robustly predicted pCR in the validation clinical trial cohort (P &lt; 0.001, AUC = 0.8). These data suggest a relevance of ceramide metabolism and the expression of kinases that sense tension across the sister chromatid pair in determining response to taxane combination chemotherapy schedules in vivo. We believe that this approach of using functional genomics in combination with gene expression datasets will improve the prediction of therapeutic response in cancer medicine.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 2032.

Consistent Principal Components from Triple Negative Breast Cancer Expression Profiles Yields Agent Specific Predictors of Chemotherapy Response

Genome scale expression profiling is likely to yield improved methods for optimizing therapy for individual breast cancer patients. Microarray based predictors of response to chemotherapy have been described for ER-positive tumors, but supervised methods haven't yielded highly accurate predictors of response in triple-negative breast cancer (TNBC). The problem of deriving predictive or prognostic classifiers is not trivial, and care must be taken to avoid pitfalls such as data set-specific noise and overfitting.To overcome these problems, we developed a two-stage unsupervised method to derive consistent metagenes from multiple data sets. In the first stage, we used principal component analysis to identify aspects of gene expression profiles that are consistently observed in multiple starting data sets. We then identified a subset of genes that best captured the information derived from these components. In the second stage, we factorized this subset of genes and derived metagenes applicable to any external data set. With this method, overfitting is eliminated by virtue of the unsupervised approach, and data set-specific noise is reduced by selecting only components presented in multiple data sets.We first applied our method to four TNBC data sets not obtained in a neoadjuvant setting and derived four metagenes. We then applied these metagenes to another four independent data sets annotated with response to various neoadjuvant therapies in order to assess their predictive performances. Two of the metagenes were associated with response: one predicted pathological complete response (pCR) in the two TFAC cohorts but not in the other two cohorts (Fig. a); the other was associated with pCR to TFAC, residual disease (RD) to epirubicin single agent, but not with response to FEC (Fig. b). Notably, these metagenes derived in an unsupervised manner were more strongly predictive than were classifiers derived using conventional supervised methods.As conclusion, we report and validate an unsupervised strategy as a robust and powerful alternative to supervised methods for deriving predictors for response to chemotherapy from microarray data. If confirmed in additional independent cohorts, these metagenes may lead to clinical tests to optimize therapy for individual TNBC patients.Figure 1. ROC curves indicate the association between two metagenes and agent-specific pathological complete response to neoadjuvant therapy.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 3163.

Computational Dissection of Tumor Expression Profiles

Gene expression profiling has yielded important insights about tumor biology that may improve treatment decisions in patients. However, it is difficult to collect a specimen of pure tumor cells, and thus microarray measurements usually reflect the contribution of tumor cells as well as stromal and other normal cells. We applied unsupervised matrix factorization methods to gene expression data to derive several sets of co-expressed genes, or signatures, that together comprise a set of independent descriptors of breast tumors. Some of these signatures correspond to specific cell types (adipocytes, lymphocytes, fibroblasts), while others reflect well-known tumor-intrinsic expression programs (ER, ERBB2, proliferation). We confirmed the specificity of the signatures using expression data from purified normal cells and tumor cell lines, microdissected tumors, and bulk tumors with corresponding histological cellularity estimates. In several data sets, cell-type signatures were highly variable and anticorrelated with tumor-intrinsic signatures, confirming that variation in normal cell content is a potential source of measurement bias.Overall, these results provide an intuitive framework for the interpetation of tumor expression profiles and may lead to an improved understanding of the physiological mechanisms involved in tumor development.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 1166.

Identification of robust, clinically relevant phenotypes of breast cancer from genome scale molecular profiling

Abstract #2036

Genome scale analysis by microarrays or array CGH holds the promise to identify novel subclasses of breast cancer or characterize functional modules of clinical relevance in a robust fashion. However, the success of these endeavors is highly dependent on several factors such as the general noise structure and noise level of high throughput measurements or the strength of association between biomarkers/gene modules and clinical outcome. We will address two issues deeply rooted in the high throughput nature of genome scale profiling, which are relevant for the accurate analysis of clinical microarray data sets: systematic bias in clinical microarray data and establishing strategies that allow extracting robust, convergent information/classification from genome scale molecular profiling of breast cancer.&#x2028; As will be demonstrated, clinical microarray data are burdened with a high level of systematic bias. We identified sources of technical bias affecting many genes in concert, thus causing spurious correlations in clinical data sets and false associations between genes and clinical variables. A method will be presented to correct for technical bias in clinical microarray data, which increased concordance with known biological relationships in multiple data sets.&#x2028; Gene expression profiling based classification of breast cancer and prognostic or clinical response associated gene expression signatures are usually derived from a single data set. However, any result extracted from a single data set will reflect to a large extent the technical (which genes are measured reliably on the microarray) and biological (such as cohort selection) bias of the given cohort. An alternative approach uses multiple, in this case 5 different, analogous clinical data sets and determines the robust, convergent information emerging from the cross data-set analysis. We will present such a method, which will reduce the impact of data set specific bias and outline robust functional modules in breast cancer, ultimately leading to the reevaluation of gene expression profiling based subtyping and diagnostic gene expression signatures in breast cancer.&#x2028; Finally, we will present evidence for the existence of at least two fundamentally different types of genome instability in breast cancer with direct implications for response to chemotherapy.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 2036.

The Effects of 10?? Reverse Trendelenburg Position on Subdural Intracranial Pressure and Cerebral Perfusion Pressure in Patients Subjected to Craniotomy for Cerebral Aneurysm

The aim of the current study was to examine the effects of 10 degrees reverse Trendelenburg position (rTp) on subdural intracranial pressure (ICP), cerebral perfusion pressure (CPP), and dural tension. Additionally, the relationship between preoperative Hunt and Hess (H and H) grade and the subdural ICP in patients scheduled for cerebral aneurysm surgery was investigated. Twenty-eight consecutive patients with a cerebral aneurysm were subjected to craniotomy in propofol/fentanyl or propofol/remifentanil anesthesia. Subdural ICP was measured after opening of the bone flap and exposure of dura. After reference measurements of subdural ICP and mean arterial blood pressure (MABP), the measurements were repeated during 10 degrees rTp. No significant differences between the anesthetic groups were disclosed. During 10 degrees rTp, a significant decrease in MABP, ICP, and jugular bulb pressure was observed whereas CPP remained unchanged. In H and H 0 patients (unruptured aneurysm), the ICP decreased from 2.9 +/- 2.6 mmHg to 0.4 +/- 2.2 mmHg at 10 degrees rTp. In H and H I to II patients, the ICP decreased from 9.3 +/- 3.8 mmHg to 4.6 +/- 3.3 mmHg at 10 degrees rTp. A significant difference in the mean baseline subdural ICP and DeltaICP (change in ICP) was found between patients with unruptured aneurysm and patients with subarachnoid hemorrhage (H&H I and II). Furthermore, the relationship between the subdural ICP at neutral position and DeltaICP was significant. In patients without intracranial hypertension, 10 degrees rTp decreases subdural ICP and dural tension in patients with ruptured as well as patients with unruptured cerebral aneurysm; CPP is unchanged.

Effect of alfentanil on intracranial pressure during propofol-fentanyl anesthesia for craniotomy. A randomized prospective dose-response study

BACKGROUND

The effect of alfentanil on intracranial pressure (ICP) in patients with supratentorial cerebral tumors has only been sparsely examined and with somewhat contradictory results.

METHODS

Thirty-one patients were anesthetized with propofol and fentanyl. After removal of the bone flap a bolus-dose of alfentanil 10 (group 1), 20 (group 2), or 30 microg kg(-1) (group 3) was administered followed by an infusion of 10, 20, or 30 microg.kg(-1).h(-1) to patients in groups 1, 2, and 3, respectively. A control group received no alfentanil. Subdural ICP, mean arterial blood pressure (MAP), and cerebral perfusion pressure (CPP) were monitored and arterial and jugular bulb blood were sampled before and every minute for 5 min after the bolus administration of alfentanil and again after 5 min of hyperventilation to be able to calculate cerebral arterio-venous oxygen content difference (AVDO2) and carbon dioxide reactivity (CO2-reactivity).

RESULTS

No changes in subdural ICP or AVDO2 from alfentanil in the study period were observed within the groups. However, alfentanil decreased MAP and CPP. The maximum CPP decrease (mean value of each group) was 4 mmHg, 8 mmHg, and 18 mmHg in groups 1, 2, and 3, respectively. There was no difference between groups as regards the CO2-reactivity.

CONCLUSION

We conclude that administration of alfentanil to propofol-fentanyl anesthetized patients with supratentorial cerebral tumors decreases MAP and CPP in a dose-related way, but does not influence subdural ICP, AVDO2 or the CO2-reactivity.

Subdural intracranial pressure, cerebral perfusion pressure, and degree of cerebral swelling in supra- and infratentorial space-occupying lesions in children

To our knowledge comparative studies of intracranial pressure (ICP) and degree of cerebral swelling during craniotomy for supratentorial or infratentorial space occupying lesion in children are not available. In this prospective study subdural ICP, cerebral perfusion pressure (CPP), dural tension, and the degree of cerebral swelling were analysed in supine and prone positioned children subjected to craniotomy for space occupying lesions.

MATERIAL AND METHOD

48 children with space occupying tumours were subjected to either isoflurane/nitrous oxide 50%/fentanyl (n = 22) or propofol/fentanyl/air/oxygen (n = 26). 25 children were operated supratentorially in supine position, while 23 patients were operated infratentorially in the prone position. Subdural ICP, mean arterial blood pressure (MABP), and CPP were measured just before opening of the dura. Dural tension was estimated before opening of dura, and the degree of cerebral swelling was estimated after opening of dura.

RESULTS

The age and weight of children anaesthetised with isoflurane in the prone position were significantly lower than the propofol anaesthetised groups. No significant inter-group differences as regards tumour size, midline shift, rectal temperature, MABP or PaCO2 were found. ICP in prone positioned children averaged 16.9 mm Hg against 9.0 mm Hg in supine positioned children (p < 0.001). In prone positioned children the dura was significantly tenser, and the degree of brain swelling after opening of dura was significantly more pronounced. No significant difference as regard ICP was disclosed when isoflurane/nitrous oxide/fentanyl and propofol/ fentanyl anaesthetized children were compared, but MABP and CPP were significantly lower in isoflurane anaesthetised children.

CONCLUSION

In children with cerebral tumours ICP is higher, and the degree of cerebral swelling more pronounced in the prone-compared with supine positioned children. Choice of anaesthesia did not influence ICP, but CPP was significantly lower during isoflurane anaesthesia.

Routine X-ray control of upper central venous lines: Is it necessary?

BACKGROUND

Insertion of central venous catheters (CVCs) is a procedure associated with a varying risk of complications, depending on the setting and the skill of the clinician who undertakes the procedure. The aim of this study was to monitor the complication rate of CVC insertion and evaluate the value of routine chest X-ray control.

METHODS

Anesthesiologists at eight hospitals filled in a questionnaire immediately after insertion of a CVC. The post-procedural clinical evaluation, including expected complications, was compared to actual radiological findings. Chest X-ray was ordered by the anesthesiologist, and described by staff radiologists.

RESULTS

The clinicians had from 2 months to 30 years of experience as anesthesiologists, and trainees inserted 34% and specialists 66% of the catheters, using landmark techniques. Over a period of 2 months, 473 CVC-insertion procedures were included in the investigation. Two patients (0.4%) had a pneumothorax: one was among the 11 cases in which the clinician suspected complications after the procedure, and another was found in a high-risk patient 13 h after CVC insertion. Both patients were treated successfully with chest tubes. The favorite approach was right vena jugularis interna with 324 (69%) catheters; of these patients one had a pneumothorax, catheter-tip placement was correctly predicted in 317 (97%), and no catheters were repositioned.

CONCLUSION

In the hands of trained clinicians, insertion of CVCs is a safe procedure. We found no value of routine X-ray control and omission of routine chest X-ray must be considered.

Neuromuscular blocking agents in neurointensive care

INTRODUCTION

Intensive care treatment of patients with severe head injury is aimed at preventing secondary injury. One of the cornerstones in this treatment is sedation and ventilation. Use of Neuromuscular Blocking Agents (NBA) has gained widespread use as part of the protocol for maintaining normal intracranial pressure values, without class 1 evidence for the efficacy of the treatment.

METHODS

We examined data of the use of NBA as infusion during ventilator treatment, and IntraCranial Pressure (ICP) measurements in the database from the international multicenter randomized double blind trial of the NMDA receptor antagonist Selfotel. No specific mode of sedation was recommended in the study protocol.

RESULTS

Of the 427 patients enrolled in the study 326 had a full data set, 138 received NBA during their stay in the ICU. There were no statistical difference in demographic data between the two groups. During their stay in the ICU, patients who received NBA had a median of 13.5 hours with a recorded ICP above 20 mm Hg, patients who did not receive NBA had a median of 6.5 hours with ICP above 20 mm Hg (p < 0.05).

CONCLUSION

Our data challenges the concept of using NBA as part of a routine sedation strategy in treatment of patients with severe head injury.

US-guided fine needle aspiration versus coarse needle biopsy of thyroid nodules

OBJECTIVE

The aim of this study was retrospectively to evaluate ultrasound (US) guided fine-needle aspiration (FNA), in combination with US-guided coarse-needle biopsies, (CNB) from solitary or dominant thyroid nodules routinely performed during a 2 year period.

METHODS

Seventy seven patients were biopsied using US-guided FNA and CNB. FNA was performed using a 21-Gauge needle and CNB using a 18-Gauge single action spring-activated needle biopsy system. The biopsies were performed with local anaesthesia. The Department of Pathology routinely examined the biopsy specimens. The retrieval rate in obtaining material for diagnostic evaluation was FNA (97%), CNB (88%), FNA and CNB (100%).

RESULTS

In all, 41 of the 77 patients underwent neck-surgery. The surgical specimens were used to determine the results of diagnosing neoplasia. The accuracy, sensitivity and specificity for FNA were 80, 83, and 77%. For CNB 86, 78, and 94%. For both FNA and CNB 80, 89 and 73%. The diagnostic value of the two methods showed no significant difference (P < 0.05). CNB revealed contrary to FNA, however, one additional cancer. Also a higher number of false positive findings was noticed using FNA. No serious complications were registered. Adequate biopsies were obtained in all the patients using the combination of US-guided FNA and CNB. No patient underwent rebiopsy.

CONCLUSIONS

The study demonstrated that neither US-guided CNB nor the combination of US-guided FNA and CNB were superior to US-guided FNA. US-guided CNB is only recommended in few selected patients.

Intracranial hypertension and cerebral perfusion pressure: influence on neurological deterioration and outcome in severe head injury. The Executive Committee of the International Selfotel Trial

OBJECT

Recently, a renewed emphasis has been placed on managing severe head injury by elevating cerebral perfusion pressure (CPP), which is defined as the mean arterial pressure minus the intracranial pressure (ICP). Some authors have suggested that CPP is more important in influencing outcome than is intracranial hypertension, a hypothesis that this study was designed to investigate.

METHODS

The authors examined the relative contribution of these two parameters to outcome in a series of 427 patients prospectively studied in an international, multicenter, randomized, double-blind trial of the N-methyl-D-aspartate antagonist Selfotel. Mortality rates rose from 9.6% in 292 patients who had no clinically defined episodes of neurological deterioration to 56.4% in 117 patients who suffered one or more of these episodes; 18 patients were lost to follow up. Correspondingly, favorable outcome, defined as good or moderate on the Glasgow Outcome Scale at 6 months, fell from 67.8% in patients without neurological deterioration to 29.1% in those with neurological deterioration. In patients who had clinical evidence of neurological deterioration, the relative influence of ICP and CPP on outcome was assessed. The most powerful predictor of neurological worsening was the presence of intracranial hypertension (ICP > or = 20 mm Hg) either initially or during neurological deterioration. There was no correlation with the CPP as long as the CPP was greater than 60 mm Hg.

CONCLUSIONS

Treatment protocols for the management of severe head injury should emphasize the immediate reduction of raised ICP to less than 20 mm Hg if possible. A CPP greater than 60 mm Hg appears to have little influence on the outcome of patients with severe head injury.

The frequency, antecedent events, and causal relationships of neurologic worsening following severe head injury. Executive Committee of the international Selfotel Trial

Neurologic deterioration observed following head injury is recognized as having a deleterious effect on outcome. The present study examines this occurrence in detail to determine the frequency of these episodes, their antecedent events and causal relationships in order to identify patients who are at risk. Data was collected prospectively from a consecutive series of 427 patients entered into the international trial of the NMDA receptor antagonist Selfotel. Using a definition of neurologic worsening based upon objective criteria, 117 patients were identified who suffered 164 episodes of deterioration. The occurrence of a single episode of neurologic worsening increased mortality by more than five-fold and reduced favorable outcomes (good or moderate on the Glasgow Outcome Scale), by more than 50%. Increased intracranial volume resulting in intracranial hypertension was the single most frequent cause of neurologic worsening. This serves to emphasize the importance of more adequate treatments of intracranial hypertension in improving the outcome of patients with severe head injury.

Neurological deterioration as a potential alternative endpoint in human clinical trials of experimental pharmacological agents for treatment of severe traumatic brain injuries. Executive Committee of the International Selfotel Trial

OBJECTIVE

A recently improved understanding of the pathophysiological features of head injuries has led to the development of new drug therapies. Accurate human clinical trials remain necessary to document the efficacy and safety of new agents. It would be helpful to decrease the time from drug development to clinical use and general availability for drugs found to be effective. Conversely, ineffective agents could be abandoned in a timely fashion.

RATIONALE

A new endpoint measure, defined as neuroworsening (NW), is an objective observable event that is identifiable during hospitalization. This may enable the efficacy of drugs to be demonstrated or disproved much earlier than with 6-month outcome assessments. The prospective, double-blind, multicenter trial of the N-methyl-D-aspartate receptor antagonist Selfotel was used to acquire data on the efficacy of NW in predicting neurological outcomes. The 6-month Glasgow Outcome Scale scores, which were the primary endpoints of that trial, were compared with the frequency of NW. NW was an observable event that could be objectively defined after head injuries. Patients who suffered one or more episodes of NW demonstrated significantly higher morbidity and mortality rates than did patients who did not.

CONCLUSION

Future trials should consider the use of NW as an outcome measure that can be included with more traditional measures in the study design. If the strong correlation demonstrated between NW and 6-month Glasgow Outcome Scale scores can be prospectively demonstrated in a successful trial, the time to approval of future agents could be decreased.

[Mycoplasma pneumonia affecting the central nervous system]

The authors describe a case of Guillain-Barré syndrome and a case of encephalitis, both with serological proven Mycoplasma pneumoniae infection. In the patient with Guillain-Barré syndrome, a 49 year old male who had neurological sequelae five months after discharge, a throat swab was PCR positive for M pneumonia. The patient with encephalitis was discharged 19 days after admission without sequelae.

[Use of bladder thermistor catheters in an intensive care unit. Comparative study of core temperature measurements with bladder thermometers and rectal thermometers in an intensive care unit]

Bladder temperature measured by a thermistor tipped urinary catheter was compared to rectal temperature in 14 ICU patients. During a period of five days 2 x 232 measurements were recorded, and good correlation was found between rectal and bladder temperatures (R = 0.97). There did not seem to be any drift in the bladder thermistor. Measurement was accurate during periods of oliguria. We find that bladder temperature measurement is reliable, safe, convenient and accurate for routine use in the ICU.

[Mycoplasma pneumoniae infection. Pulmonary and extrapulmonary manifestations]

Mycoplasma pneumoniae is known to cause a mild disease of the upper respiratory tract and uncomplicated pneumonia in infected individuals. Serious pulmonary and extrapulmonary complications are reported with increasing frequency. In this paper pulmonary, neurological, haematological, dermatological, cardial, gastrointestinal and renal complications are reviewed. Since the diagnosis requires laboratory confirmation and indeed is often retrospective, knowledge of the less known pulmonary and systemic manifestations is important to make proper diagnostic decisions and to ensure proper medical treatment.

[Extracorporeal shockwave crushing of gallstones. Preliminary report]

Extracorporeal shock wave lithotripsy (ESWL) was used for treatment of symptomatic x-ray negative stones in 23 patients. The number of ESWL sessions per patient was 1.8 (range 1-4). In 18 patients (78%), adequate fragmentation was seen comparable to results obtained elsewhere. Oral bile acid therapy was used after ESWL in the 18 patients mentioned and the mean follow-up period was five months (range 3-8 months). Four patients had by now passed all stones while 12 patients still had remaining stone fragments and one patient a gallstone. After ESWL, one patient was and one patient a gallstone. After ESWL, one patient was referred for cholecystectomy at his own request. Of the remaining five patients, cholecystectomy was performed in two and was scheduled for in three. Complications after ESWL were seen in two patients who developed acute pancreatitis. Thus, our preliminary experience shows that ESWL resulted in fragmentation and passing of gallbladder stones, but not without complications. Like the gallstone groups in Lyon, Montreal and Munich we are convinced that ESWL should be performed in accordance with prospectively designed protocols in order to establish optimal planning of indications and strategies for future treatment.

Surecut 0.6 mm liver biopsy in the diagnosis of cirrhosis

Liver biopsy with the 0.6 mm (23 gauge) Surecut needle was compared to conventional Menghini biopsy in the diagnosis of cirrhosis. Seventy-seven consecutive patients (mainly alcoholics) with a clinical indication for liver biopsy had both biopsies performed simultaneously. In 71 patients sufficient material for a morphological diagnosis concerning liver architecture was obtained with both biopsy techniques (Surecut insufficient in 5 cases and Menghini insufficient in 2 cases). The biopsies were classified as cirrhosis or non-cirrhosis. There was agreement in 69 cases (97%, confidence limits 90-100%). Using the result of the Menghini biopsy as the final diagnosis, the predictive values for a positive and negative diagnosis for the Surecut needle were 96% and 98%, respectively. There were no complications to either of the biopsies. It is suggested that the 0.6 mm Surecut biopsy may be used in the diagnosis of cirrhosis in cases where conventional Menghini needle biopsy is contraindicated.

Ultrasonically guided percutaneous treatment of liver abscesses

Twenty-two patients with liver abscesses demonstrated by ultrasonography (US) were treated over a nine-year period. The diagnosis was in all cases verified by puncture. The patients were treated by US-guided puncture or catheter drainage. Seventeen patients (77%) were cured without surgical drainage. Four patients were cured after subsequent surgical intervention. One patient died later of pancreatic carcinoma. There were no complications from the US-guided therapy. For the treatment of liver abscesses we recommend US-guided drainage as the first choice. Close collaboration between surgeon and radiologist is mandatory since some of these patients still need surgical treatment.

Doctors' requirements for reproducibility of diagnostic information

Two radiologists independently assessed 100 leg vein phlebograms for the presence or absence of deep venous thrombosis. In a subsequent questionnaire, 66 physicians were asked to state the level of agreement they would require to use conventional phlebography in their diagnostic decisions, and whether they would reduce their requirements if the phlebographic technique were made less painful and less expensive. The responses indicated physicians' requirements for reproducibility of a well-known routine diagnostic method may be unrealistic, and that physicians do not consider the inconvenience of an examination to the patient or its cost in setting their requirements for diagnostic precision.

Ultrasonically guided 125iodine seed implantation with external radiation in management of localized prostatic carcinoma

Thirty-three patients with localized prostatic carcinoma (16 poorly differentiated) were treated with transperineal 125Iodine seed implantation (160 Gy) guided by transrectal ultrasonography and subsequent external beam irradiation (47.4 Gy). The observation time was six to sixty-eight months with a median follow-up of thirty-five months. Median change in prostatic volume was a reduction of 35 percent. Re-biopsy or transurethral resection of the prostate was performed in 25 patients after one to two years, revealing still malignant histology in 12 (48%). Development of distant metastases occurred in 14 patients (44%), and 8 have died of prostatic cancer. Fourteen patients suffered from late complications of which surgical intervention was indicated in 3 cases.

Abdominal ultrasound versus intravenous urography in the evaluation of infravesically obstructed males

In a prospective study intravenous urography (IVP) and abdominal ultrasonography (US) were compared in 100 consecutively admitted male patients with symptoms of infravesical obstruction. No pathology was found in 67 patients on IVP and in 61 patients on US. Both modalities disclosed 5 bilateral, 4 unilateral hydronephroses and one patient with contracted kidneys. IVP found 7 renal masses: one solid tumour, 2 "possibly solid" tumours and 4 "possibly cysts", whereas US found one solid tumour and 16 cysts. Both modalities detected 3 kidney stones, 5 bladder stones and 3 bladder tumours. It is concluded that "imaging" of the urinary tract is only indicated in cases of haematuria, elevated creatinine, history of renal calculous disease and other clinical suspicion of upper urinary tract disease. It is further concluded that US is preferable to IVP in this patient category due to (1) better characterization of renal masses, (2) the possibility of investigating the liver and the retroperitoneum in the same setting, (3) better evaluation of the prostate with respect to size, (4) better evaluation of the bladder, and (5) last but not least for economical reasons. However, bone metastases will be missed.

The polyploidizing growth pattern of normal rat liver is replaced by divisional, diploid growth in hepatocellular nodules and carcinomas

DNA content was measured by flow cytometry in isolated nuclei from 71 neoplastic nodules and 15 hepatocellular carcinomas isolated from rat liver at various times after treatment with an initiation--promotion regimen employing diethylnitrosamine and 2-acetylaminofluorene. Nodules and carcinomas contained mostly diploid nuclei as compared with both surrounding and normal hepatocytes which were predominantly polyploid. There appears to be a positive correlation between the degree of diploidy in nodules and their rate of proliferation. No aneuploid populations were identified in any neoplasm despite good peak resolution. These results show that an alteration in proliferation pattern from normal polyploidizing growth to diploid--diploid divisional growth is a consistent characteristic throughout the carcinogenic process in our experimental model.

Tetracycline for sclerosis of thyroid cysts. A randomized study

In a prospective study, 53 consecutive patients with solitary thyroid cysts were randomized to ultrasonically guided cyst aspiration and subsequent flushing with isotonic saline (n = 30) or tetracycline hydrochloride (n = 23). The patients were followed up clinically and ultrasonically 1, 3, 6, and 12 months after treatment. If the cyst recurred, a repeated treatment was offered. Cure was defined as the absence of any residual nodule and an ultrasonic cyst volume of less than 1 mL 12 months after the last treatment. During follow-up, two patients without recurrence after saline treatment and six patients without recurrence after tetracycline treatment developed solid cold nodules. Fourteen (47%) of 30 patients in the saline group and ten (43%) of 23 patients in the tetracycline group were cured (not statistically significant). Tetracycline does not seem to offer any advantage over isotonic saline in the treatment of thyroid cysts, and some of these patients still need thyroid surgery.

The long-term influence of vasectomy on prostatic volume and morphology in man

During the past two decades several papers have described the changes in prostatic secretory capacity following vasectomy. Based upon results indicating a reduction of secretory function, it was suggested that even prostatic size and the incidence of benign prostatic hyperplasia (BPH) might be altered after the operation. In this study, which included 56 males who had been vasectomized 8 years previously and 56 age-matched control persons, transrectal ultrasonic scanning of the prostate was used for exact measurements of the prostatic volume and for the investigation of intraprostatic echo pattern. The total prostatic volume, the volume of the periurethral gland, and the volume of the peripheral zone were not influenced by the vasectomy; nor was the growth rate of these zones affected. In the vasectomy group, the frequency of adenomatous prostates was 19.6%, whereas 30.3% of prostates in the control group had ultrasonic signs of BPH. However, this is not a statistically significant difference. Subdividing the material according to age did not reveal altered BPH frequency in any age group when vasectomized and controls were compared.

Ultrasound-guided percutaneous nephrostomy in the treatment of advanced gynecologic malignancy

Adjuvant to cancer therapy, 35 percutaneous ultrasound-guided nephrostomies have been applied in 21 patients with ureteral occlusions or lesions secondary to advanced gynecologic malignancies. Application of the catheters was uncomplicated. Dislodgement of the catheters was the major problem with this technique, occurring in 9 cases. There were no serious complications. In 14 patients, normal ureteral function was restored after the cancer therapy, 2 had to be nephrectomized, and in 5 patients the nephrostomies had to remain permanently. It is concluded that nephrostomy is a useful tool in the management of advanced gynecologic malignancies in patients who have a prospect of cure or a period of meaningful tumor regression.

Bladder tumor staging by transurethral ultrasonic scanning

To determine tumor stage, 115 bladder cancer patients with cystoscopic suspicion of invasion underwent transurethral ultrasonic scanning. Seventeen patients who had received radiotherapy were excluded because it proved impossible to differentiate between tumor and irradiation sequelae. Of the remaining 98 examinations, 4 (4.1%) were inconclusive, 73 tumors (74.5%) were correctly staged, 16 tumors (16.3%) were overstaged and 5 tumors (5.1%) understaged. Transurethral ultrasound is regarded a useful supplement to cytoscopy and biopsy in staging of bladder tumors suspected of invasion.

Electron microscopy of ultrasound-guided fine-needle biopsy specimens

A prospective 3-year study was undertaken in order to assess the value of electron microscopy (EM) as a supplement to routine light microscopy (LM) in ultrasound-guided fine-needle biopsy of suspected abdominal and retroperitoneal tumours. Eight-six of the 899 ultrasound-guided fine-needle biopsies performed during this period were supplemented with EM using the following indications: metastatic lesions with unknown primary tumour, primary retroperitoneal tumours, tumours with atypical clinical histories and where the primary LM evaluation was unable to determine tumour cell type. Two methods of obtaining material for EM were tested, namely, fine-needle aspiration and fine-needle histological biopsy (Surecut). Both methods yielded suitable material for EM evaluation in approximately 80% of the 76 cases where tumour cells were identified by LM. However, it was technically easier to process material for EM when obtained by fine-needle histological biopsy. The results of the 62 cases where suitable material for EM was obtained were grouped according to the histopathological and clinical value of the diagnosis. In 23 cases (37%) EM was without additional diagnostic value. In 12 cases (19%), EM supplied a more precise histopathological diagnosis, but the diagnostic gain was without clinical significance. In 27 cases (44%) EM was of significant clinical value, as the diagnosis by itself was enough to change the investigative procedure and/or the treatment of the patient.

Ultrasonographic diagnosis of renal stones

To illucidate the diagnostic accuracy of ultrasound in the detection of renal stones we performed a blind comparative study of ultrasonography and i.v. urography. In 92 kidneys with 58 stones, 10 stones smaller than 6 mm were overlooked by ultrasound, whereas all stones 6 mm or larger were correctly detected. In one case of uric acid stone disease i.v. urography was inconclusive in determining the true nature of a renal pelvic filling defect, whereas ultrasound correctly diagnosed a stone. We conclude that ultrasonography has a place in diagnosis and control of renal stones.

Bladder tumour control by abdominal ultrasound and urine cytology

A blind study comparing abdominal ultrasound and cystoscopy was carried out in 186 patients. 20 bladder tumours sized from 2 to 5 mm were overlooked. Combination with urine cytology increased the diagnostic sensitivity. In order to reduce costs and patient inconvenience in the bladder tumour control population abdominal ultrasound and urine cytology is advocated as an alternative to cystoscopy. This control modality seems safe in patients with "low-risk" bladder tumour disease.

Comparison of ultrasonography and transhepatic cholangiography in the evaluation of obstructive jaundice

The diagnostic value of ultrasonography and percutaneous cholangiography was compared in 114 consecutive patients with obstructive jaundice. The final diagnosis was obtained by surgery or autopsy. Transhepatic cholangiography diagnosed obstruction and its level in all patients, whereas ultrasonography failed to find obstruction in 3 patients and was unable to determine the level in 11 patients. The cause of obstruction was correctly assessed in 106 patients by transhepatic cholangiography and in 74 by ultrasonography. In 15 patients with obstruction caused by common duct calculi ultrasonography only diagnosed the five, and in 9 patients malignant obstruction was diagnosed as calculi. Ultrasonography is a reliable tool for diagnosis of obstructive jaundice and in most cases for localisation of the level of the obstruction. However, diagnosis of the cause of obstruction and of its precise topography requires direct cholangiography.

Ultrasonically guided fine needle aspiration biopsy of renal masses

A consecutive series of 301 ultrasonically guided fine needle aspiration biopsies of renal masses was reviewed. The retrieval rate was 95 per cent and a correct cytological diagnosis was established in 82 per cent of the cases. There were 14 false positive aspirates, for a predictive value of a malignant aspirate of only 93 per cent. All false positive results were misinterpreted as relatively well differentiated adenocarcinoma. We conclude that renal fine needle aspiration biopsy may add information but the risk of a false positive finding must always be considered.

Influence of vasectomy on the volume of the non-hyperplastic prostate in men

The influence of vasectomy on the volume of the non-hyperplastic prostate was investigated in 24 men referred consecutively for vasectomy. A comparison of trans-rectal prostatic volume determined ultrasonically before vasectomy and three months post-operatively revealed a highly significant decrease (P less than 0.01) in the volume of the peri-urethral portion of the gland. The volume of the outer zone of the prostate did not change significantly (P greater than 0.1). This may indicate that the prostate is not a functionally homogenous organ. It is postulated that there may be a local influence on the prostate via a hormone transported in the deferent duct and/or the deferential vein.