Modifications of the National Early Warning Score for patients with chronic respiratory disease

BACKGROUND

The National Early Warning Score (NEWS) uses physiological variables to detect deterioration in hospitalized patients. However, patients with chronic respiratory disease may have abnormal variables not requiring interventions. We studied how the Capital Region of Denmark NEWS Override System (CROS), the Chronic Respiratory Early Warning Score (CREWS) and the Salford NEWS (S-NEWS) affected NEWS total scores and NEWS performance.

METHODS

In an observational study, we included patients with chronic respiratory disease. The frequency of use of CROS and the NEWS total score changes caused by CROS, CREWS and S-NEWS were described. NEWS, CROS, CREWS and S-NEWS were compared using 48-h mortality and intensive care unit (ICU) admission within 48 h as outcomes.

RESULTS

We studied 11,266 patients during 25,978 admissions; the use of CROS lowered NEWS total scores in 40% of included patients. CROS, CREWS and S-NEWS had lower sensitivities than NEWS for 48-h mortality and ICU admission. Specificities and PPV were higher. CROS, CREWS and S-NEWS downgraded, respectively, 51.5%, 44.9% and 32.8% of the NEWS total scores from the 'mandatory doctor presence' and 'immediate doctor presence and specialist consultation' total score intervals to lower intervals.

CONCLUSION

Capital Region of Denmark NEWS Override System was frequently used in patients with chronic respiratory disease. CROS, CREWS and S-NEWS reduced sensitivity for 48-h mortality and ICU admission. Using the methodology prevalent in the NEWS literature, we cannot conclude on the safety of these systems. Future prospective studies should investigate the balance between detection rate and alarm fatigue of different systems, or use controlled designs and patient-centred outcomes.

Respiratory rates measured by a standardised clinical approach, ward staff, and a wireless device

BACKGROUND

Respiratory rate is among the first vital signs to change in deteriorating patients. The aim was to investigate the agreement between respiratory rate measurements by three different methods.

METHODS

This prospective observational study included acutely admitted adult patients in a medical ward. Respiratory rate was measured by three methods: a standardised approach over 60 s while patients lay still and refrained from talking, by ward staff and by a wireless electronic patch (SensiumVitals). The Bland-Altman method was used to compare measurements and three breaths per minute (BPM) was considered a clinically relevant difference.

RESULTS

We included 50 patients. The mean difference between the standardised approach and the electronic measurement was 0.3 (95% CI: -1.4 to 2.0) BPM; 95% limits of agreement were -11.5 (95% CI: -14.5 to -8.6) and 12.1 (95% CI: 9.2 to 15.1) BPM. Removal of three outliers with huge differences lead to a mean difference of -0.1 (95% CI: -0.7 to 0.5) BPM and 95% limits of agreement of -4.2 (95% CI: -5.3 to -3.2) BPM and 4.0 (95% CI: 2.9 to 5.0) BPM. The mean difference between staff and electronic measurements was 1.7 (95% CI: -0.5 to 3.9) BPM; 95% limits of agreement were -13.3 (95% CI: -17.2 to -9.5) BPM and 16.8 (95% CI: 13.0 to 20.6) BPM.

CONCLUSION

A concerning lack of agreement was found between a wireless monitoring system and a standardised clinical approach. Ward staff's measurements also seemed to be inaccurate.

End points for validating early warning scores in the context of rapid response systems: a Delphi consensus study

INTRODUCTION

When investigating early warning scores and similar physiology-based risk stratification tools, death, cardiac arrest and intensive care unit admission are traditionally used as end points. A large proportion of the patients identified by these end points cannot be saved, even with optimal treatment. This could pose a limitation to studies using these end points. We studied current expert opinion on end points for validating tools for the identification of patients in hospital wards at risk of imminent critical illness.

METHODS

The Delphi consensus methodology was used. We identified 22 experts based on objective criteria; 17 participated in the study. Each expert panel member's suggestions for end points were collected and distributed to the entire expert panel in anonymised form. The experts reviewed, rated and commented the suggested end points through the rounds in the Delphi process, and the experts' combined rating of the usefulness of each suggestion was established.

RESULTS

A gross list of 86 suggestions for end points, relating to 13 themes, was produced. No items were uniformly recognised as ideal. The themes cardiac arrest, death, and level of care contained the items receiving highest ratings.

CONCLUSIONS

End points relating to death, cardiac arrest and intensive care unit admission currently comprise the most obvious compromises for investigating early warning scores and similar risk stratification tools. Additional end points from the gross list of suggested end points could become feasible with the increased availability of large data sets with a multitude of recorded parameters.

Management of Bleeding Duodenal Varices with Combined TIPS Decompression and Trans-TIPS Transvenous Obliteration Utilizing 3% Sodium Tetradecyl Sulfate Foam Sclerosis

OBJECTIVES

Endoscopic experience in the management of duodenal varices (DVs) is limited and challenging given the anatomic constraints and limited experience. The endovascular management of DVs is not yet established and the controversy of whether to manage them by decompression with a transjugular intrahepatic portosystemic shunt (TIPS) or by transvenous obliteration is unresolved. In the literature, the 6-12 month rebleeding rate of DVs after TIPS is 21-37% and after transvenous obliteration is 13%. The purpose of the study is to evaluate the clinical outcome of combined TIPS decompression and transvenous obliteration/sclerosis.

MATERIALS AND METHODS

This is a retrospective study (case series) of two institutions, evaluating patients who underwent TIPS and/or transvenous obliteration/sclerosis for bleeding DVs (from January 2009 to June 2013). TIPS was performed according to a standard procedure using covered stents. Transvenous obliteration (variceal sclerosis) from the systemic and/or portal venous circulation was performed utilizing 3% sodium tetradecyl sulfate foam. Transvenous obliteration was commonly augmented with coils and/or vascular plugs. Technical (technical success of establishing TIPS and completely obliterating the DVs) and clinical outcomes (rebleeding rate and survival) were evaluated.

RESULTS

Five patients with liver cirrhosis presenting with bleeding DVs were included in the study with all eventually (and coincidentally) receiving TIPS and transvenous obliteration. Two of the five patients underwent concomitant TIPS and transvenous obliteration in the same procedural setting. However, three patients underwent transvenous obliteration due to bleeding despite a patent TIPS that had been previously placed. The average time from TIPS placement to transvenous obliteration was 125 days (range: 3-324 days). After having both procedures, there was no rebleeding in the patients during a mean follow-up period of 22 months (6-50 months). Coils and/or metallic vascular plugs were used to augment the sclerosant obliteration in four of five patients.

CONCLUSION

The combination of TIPS decompression and foam sclerosant transvenous obliteration appears to be effective in preventing rebleeding in this limited case series and compares favorably with the existing evidence for either approach [TIPS or balloon-occluded retrograde transvenous obliteration (BRTO)] alone.

Ectopic varices: anatomical classification, hemodynamic classification, and hemodynamic-based management

Ectopic varices are dilated splanchnic (mesoportal) veins/varicosities and/or are dilated portosystemic collaterals that can occur along the entire gastrointestinal tract outside the common pathologic variceal sites. Ectopic varices are complex and highly variable entities that are not fully understood. Ectopic varices represent 2%-5% of a gastrointestinal tract variceal bleeding. However, ectopic varices have a 4-fold increased risk of bleeding when compared with esophageal varices and can have a mortality rate as high as 40%. All treatment strategies and techniques have been utilized in managing these potentially mortal varices and have shown poor outcomes. The debate of whether to manage these varices by decompression with a transjugular portosystemic shunt, or other portosystemic shunts, vs transvenous obliteration is unresolved. The rebleed rates after transjugular portosystemic shunt decompression are 20%-40%. The rebleed rates after transvenous obliteration and the mortality rate at 3-6 months are 30%-40% and 50%-60%, respectively. Hemodynamically from an etiology standpoint, there are 2 types: occlusive (type-b) and nonocclusive (oncotic or type-a). Hemodynamically from a vascular-shunting standpoint, there could be a component of portoportal or portosystemic shunting or both with varying dominance. This is the basis of the new classification system described herein. Management strategies (decompression vs sclerosis) are discussed. The ideal management strategy is a treatment that leads to prompt hemostasis but also addresses the etiology or hemodynamics of the ectopic varices. It is the hope that with better understanding, description, and categorization of ectopic varices comes a more systematic approach to this rare but menacing problem.

The Effect of Balloon-Occluded Transvenous Obliteration of Gastric Varices and Gastrorenal Shunts on the Hepatic Synthetic Function

Purpose:

To evaluate the effect of balloon-occluded transvenous obliteration (BRTO) on the model for end-stage liver disease (MELD) and the Child-Pugh (C-P) score and their individual components.

Methods:

A retrospective review of patients undergoing only BRTO without transjugular intrahepatic portosystemic shunt was performed (08, 2007 to 06, 2010). Pre- and post-BRTO MELD and C-P scores were calculated. The post-BRTO MELD and C-P score samplings were categorized as (1) immediate (within 14 days), (2) early (14-90 days), and (3) delayed (90-180 days) post-BRTO. The C-P and MELD scores and their individual components before and after (various sample intervals) were compared.

Results:

A total of 29 consecutive successful BRTO procedures were found and assessed. In all, 26 had immediate post-BRTO sampling (average 1.8 days after BRTO), 13 (57%) had an early post-BRTO sampling (average 47 days from BRTO), and 10 (38%) had a delayed post-BRTO sampling (average 121 days from BRTO). The bilirubin rises significantly ( P = .007) within days after BRTO, but synthetic function improves significantly between 1.5 and 4.0 months post-BRTO (international normalized ration: P = .02, bilirubin: P = .027, and albumin: P = .012). However, 31% (N = 8/ 26) of the patients had worsening ascites with or without hydrothorax. The MELD score significantly improved circa 4 months post-BRTO (from 14.1 to 10.7, P = .0008). However, the C-P score did not change significantly (from 7.6 to 6.7, P = .063).

Conclusion:

The BRTO has a positive effect on the hepatic synthetic function. However, there is a high incidence of post-BRTO ascites (31% of the patients). As a result, the MELD score appears to be a more sensitive gauge for hepatic synthetic function compared to the C-P score for patients undergoing BRTO.

Balloon-occlusion catheter rupture during balloon-occluded retrograde transvenous obliteration of gastric varices utilizing sodium tetradecyl sulfate: incidence and consequences

Balloon-occluded retrograde transvenous obliteration (BRTO) is an established procedure for the management of bleeding gastric varices in Asia. Invariably, the sclerosant utilized in Asia is ethanolamine oleate and the inventory used (vascular sheaths, balloon-occlusion catheters, and microcatheters) is not available outside Asia. A total of 41 BRTO procedures were performed with a technical and obliterative (gastric varix obliteration) success rate of 95% (n = 39 of 41) and 85% (n = 35 of 41), respectively. Complications were 4.9% (n = 2/41). A total of 6 balloon ruptures occurred (14.6%, n = 6 of 41). One rupture (16.7%, n = 1 of 6 of ruptures) lead to a technical failure and 2 ruptures (33.3%, n = 2 of 6 of ruptures) lead to an obliterative failure. Balloon rupture contributed to 50% of technical failures (n = 1/2, P = .274) and 33% of obliteration failures (n = 2/6, P = .148). In conclusion, the incidence of balloon-occlusion catheter rupture utilizing 3% sodium tetradecyl sulfate (STS) and inventory unique to the United States is significantly higher than in Asia (<8% rupture rate). However, these ruptures have no significant technical or clinical consequences.

Prevalence, presentation, and endovascular management of hemodynamically or clinically significant arterio-portal fistulae in living and cadaveric donor liver transplant recipients

PURPOSE

To compare the prevalence (cadaveric vs. living donor transplants), clinical features, and the effectiveness of endovascular management of significant arterio-portal fistulae (APF) in liver transplant recipients.

METHODS

A retrospective audit of liver transplant recipients in two institutions was performed (1996-2009). Significant APF were included and were defined as symptomatic and/or hemodynamically significant (causing graft dysfunction and/or having abnormal Doppler findings in the portal vein). Patients with significant APF were evaluated for presenting symptoms, imaging features, size/branch order portal vein involvement, and effectiveness of the endovascular management (coil embolization).

RESULTS

Four significant APF were found in 1992 (0.2%) liver transplants. Two were symptomatic and two were asymptomatic but were hemodynamically significant with liver function test abnormalities. All four APF were found in cadaveric donor graft recipients (0.23%, N = 4/1753) and none in 239 living donor graft recipients. However, there was no statistical difference between cadaveric and living donor graft recipients (p = 1.0, odds ratio = 1.23). Coil embolization was technically and clinically successful in all 4 without complications and causing normalization of the abnormal Doppler findings.

CONCLUSION

Significant APF are a rare diagnosis (0.2% of transplants). Coil embolization is a safe and effective treatment option for APF in transplants.

Hydrophobic interaction and charge accumulation at the diamond-electrolyte interface

The hydrophobic interaction of surfaces with water is a well-known phenomenon, but experimental evidence of its influence on biosensor devices has been lacking. In this work we investigate diamond field-effect devices, reporting on Hall effect experiments and complementary simulations of the interfacial potential at the hydrogen-terminated diamond/aqueous electrolyte interface. The interfacial capacitance, derived from the gate-dependent Hall carrier concentration, can be modeled only when considering the hydrophobic nature of this surface and its influence on the structure of interfacial water. Our work demonstrates how profoundly the performance of potentiometric biosensor devices can be affected by their surfaces' hydrophobicity.

Training trauma teams in the Nordic countries: an overview and present status

BACKGROUND

During the last decade there has been an increased interest in the organisation and quality of trauma care in the Nordic countries. Still, most patients are initially cared for at hospitals with low caseloads of severe trauma. More than 200 hospitals offer initial care to trauma patients. Training of trauma teams using simulators or simulated patients has evolved in the same period, as one important factor to overcome lack of practical training. This overview describes the present state of trauma team training in the Nordic countries.

METHODS

Members of a Nordic working group on the use of simulation in medicine reviewed present literature on training with simulation and described the present use of team training in their own countries during winter 2004.

RESULTS

There is an increasing amount of evidence indicating that training of teams with simulation reduces treatment errors and improves performance. The training activities do not need to be complex, but skilled debriefing seems necessary. Few Nordic hospitals train their trauma teams. The training activities vary considerably between and within countries.

CONCLUSION

There is considerable evidence supporting an increased use of experience gained in other high-risk domains where training in communication, leadership and decision-making is the focus for safety and improvement efforts. There is a need for more widespread training of trauma teams. The different training activities actually undertaken should be scientifically evaluated.

Implementation of team training in medical education in Denmark

In the field of medicine, team training aiming at improving team skills such as leadership, communication, co-operation, and followership at the individual and the team level seems to reduce risk of serious events and therefore increase patient safety. The preferred educational method for this type of training is simulation. Team training is not, however, used routinely in the hospital. In this paper, we describe a framework for the development of a team training course based on need assessment, learning objectives, educational methods including full-scale simulation and evaluations strategies. The use of this framework is illustrated by the present multiprofessional team training in advanced cardiac life support, trauma team training and neonatal resuscitation in Denmark. The challenges of addressing all aspects of team skills, the education of the facilitators, and establishment of evaluation strategies to document the effect of the different types of training on patient safety are discussed.

Implementation of team training in medical education in Denmark

In the field of medicine, team training aiming at improving team skills such as leadership, communication, co-operation, and followership at the individual and the team level seems to reduce risk of serious events and therefore increase patient safety. The preferred educational method for this type of training is simulation. Team training is not, however, used routinely in the hospital. In this paper, we describe a framework for the development of a team training course based on need assessment, learning objectives, educational methods including full-scale simulation and evaluations strategies. The use of this framework is illustrated by the present multiprofessional team training in advanced cardiac life support, trauma team training and neonatal resuscitation in Denmark. The challenges of addressing all aspects of team skills, the education of the facilitators, and establishment of evaluation strategies to document the effect of the different types of training on patient safety are discussed.

Residents lack knowledge and practical skills in handling the difficult airway

BACKGROUND

Full-scale simulators have been developed in anaesthesia. We aimed at assessing Danish anaesthesia residents' knowledge and management of a standardized difficult airway situation in an advanced airway simulator. The reliability of the assessment was also determined.

METHODS

Thirty-six residents answered a questionnaire testing their knowledge on difficult airway management and practice patterns. Secondly, all residents attempted management of a standardized 'cannot ventilate, cannot intubate' airway scenario. Three observers independently assessed a video recording of the performance.

RESULTS

Only 17% of the residents passed the written test. Ninety-seven per cent stated that they had difficulties recalling the American Society of Anesthesiologists'(ASA) difficult airway algorithm and 53% did not know how to oxygenate through the cricothyroid membrane. Seventeen per cent had previously been involved in emergency situations with severe complications due to insufficient airway management. In the scenario 75% of the residents established ventilation using a laryngeal mask airway. After establishing ventilation, 26% would continue with surgery without a definitive airway, despite the risk of aspiration. Analysis of the interobserver agreement showed good (Kappa = 0.63) to excellent (Kappa = 0.78) consistency for objective parameters in the scoring scheme. Inter-observer reliability was satisfactory (R = 0.43) for trained Crisis Resource Management evaluators.

CONCLUSIONS

Theoretical and practical education in difficult airway management needs to be improved among Danish anaesthesia residents. Simulator assessment should only be performed using well-defined objective parameters and trained assessors.

[Survey of the availability and utilization of Doppler ultrasound in German-speaking areas]

The study was performed about the spread and usage of Doppler ultrasound measurements. Standardised questionnaires were sent to the obstetrical departments of 253 universities and teaching hospitals. 59% of the hospitals answered the questions. At the university departments, the method was used regularly. On the average twice the number of patients have been examined compared to the teaching hospitals. The obstetricians in the university departments were more experienced in safety determinations and quality control. Most of the university departments used their own norm curves. When measuring the resistance in the favoured vessels umbilical artery, middle cerebral artery and arcuate arteries, the resistance index (RI) was preferred to the pulsatility Index (PI) in both kinds of hospitals. The most severe pathological findings, zero and reverse flow, occurred with an incidence of more than 2% only in hospitals with less than 500 patients a year, indicating false positive results due to inexperienced physicians. Relevant software is not commercially available; therefore documentation and evaluation of the data was done manually in most of the departments. There are different opinions about the use of Doppler ultrasound as a screening test. However, Doppler ultrasound is seen as a valuable method for diagnosis of hypoxia especially in cases of intrauterine growth retardation and pregnancy-induced hypertension. In the year 2000 the method might be widely used in nearly every small hospital and even in offices. This development without adequate training of the obstetricians might result in a high incidence of false positive results.

Hyponatremia and hyperkalemia associated with idiopathic or experimentally induced chylothorax in four dogs

Two dogs with idiopathic chylothorax and 2 dogs with experimentally induced (ie, ligation of the cranial vena cava) chylothorax were treated by intermittent thoracic drainage. Of these 4 dogs, 3 that did not have evidence of renal failure had normal or near-normal serum sodium and potassium concentrations before thoracic drainage began, and all 3 developed repeatedly marked hyponatremia and hyperkalemia during thoracic drainage. Another dog became weak and depressed, ostensibly because of hyperkalemia. Serum sodium and potassium concentrations in 1 dog with spontaneous chylothorax returned to normal after chylothorax resolved and thoracic drainage was stopped. The other 3 dogs died or were euthanatized, and the effect of stopping thoracic drainage could not be evaluated. In 3 dogs in which it was measured, normal-to-high plasma cortisol concentration was observed before and after adrenocorticotropin administration, and 2 dogs also had hyperaldosteronemia. Hyponatremia was hypothesized to be caused by sodium loss via thoracic drainage whereas hyperkalemia may have been multifactorial in origin, but probably was attributable, at least, in part to decreased renal potassium clearance.