New porcine test-model reveals remarkable differences between algorithms for spectrophotometrical haemoglobin saturation measurements with VLS.

UNLABELLED: The study created an 'ex vivo' model to test different algorithms for measurements of mucosal haemoglobin saturation with visible light spectrophotometry (VLS). The model allowed comparison between algorithms, but it also allowed comparison with co-oximetry using a 'gold standard' method. This has not been described before. Seven pigs were used. They were perfused with cold Haemaxel, and thus killed, chilled and becoming bloodless. The bronchial artery was perfused with cold blood with known saturation and spectrophotometrical measurements were made through a bronchoscope. Based on 42 spectrophotometrical measurements of porcine bronchial mucosa saturation with fully oxygenated blood and 21 with de-oxygenated blood, six algorithms were applied to the raw-spectra of the measurements and compared with co-oxymetry. The difference from co-oxymetry in the oxygenated and de-oxygenated state ranged from -32.8 to +29.9 percentage points and from -5.0 to +9.2 percentage points, respectively. CONCLUSION: the algorithms showed remarkable in-between differences when tested on raw-spectra from an 'ex vivo' model. All algorithms had bias, more marked at high oxygenation than low oxygenation. Three algorithms were dis-recommended.

Abdominal auscultation does not provide clear clinical diagnoses.

INTRODUCTION: Abdominal auscultation is a part of the clinical examination of patients, but the determining factors in bowel sound evaluation are poorly described. The aim of this study was to assess inter- and intra-observer agreement in physicians' evaluation of pitch, intensity and quantity in abdominal auscultation. MATERIAL AND METHODS: A total of 100 physicians were presented with 20 bowel sound recordings in a blinded set-up. Recordings had been made in a mix of healthy volunteers and emergency patients. They evaluated pitch, intensity and quantity of bowel sounds in a questionnaire with three, three and four categories of answers, respectively. Fleiss' multi-rater kappa (κ) coefficients were calculated for inter-observer agreement; for intra-observer agreement, calculation of probability was performed. RESULTS: Inter-observer agreement regarding pitch, intensity and quantity yielded κ-values of 0.19 (p < 0.0001), 0.30 (p < 0.0001) and 0.24 (p < 0.0001), respectively, corresponding to slight, fair and fair agreement. Regarding intra-observer agreement, the probability of agreement was 0.55 (95% confidence interval (CI): 0.51-0.59), 0.45 (95% CI: 0.42-0.49) and 0.41 (95% CI: 0.38-0.45) for pitch, intensity and quantity, respectively. CONCLUSION: Although relatively poor, observer agreement was slight to fair and thus better than expected by chance. Since the diagnostic value of auscultation increases with addition of history and clinics, and may be further improved by systematic training, it should still be used in the examination of patients with acute abdominal pain. FUNDING: not relevant. TRIAL REGISTRATION: not relevant.

[Kaposiform haemangioendothelioma in the small intestine of a three year-old boy]. / Kaposiformt hæmangioendoteliom i tyndtarmen hos en treårig dreng.

Kaposiform haemangioendothelioma is a rare, locally aggressive vascular tumour, which is mainly found in children. Typically, it occurs in the skin. The tumour is borderline malignant due to its rapid infiltrative growth. Metastasis has not been described. Since 1993, when this tumour was first defined, less than 160 cases have been reported. To our knowledge, this is the first case of kaposiform haemangioendothelioma in the gastrointestinal tract. We report a case of a three year-old boy, who presented with small bowel obstruction due to invagination of a kaposiform haemangioendothelioma.

Tissue hypoxaemia causes oedema, inflammation and fibrosis in porcine bronchial transsection.

OBJECTIVES: Bronchial artery revascularization in lung transplantation is disputed. This study examined the physiological consequences of porcine bronchial transsection and reanastomosis with and without bronchial artery blood supply with relation to lung transplantation. DESIGN: Translational, controlled animal study. Twelve pigs were operated through a left lateral thoracotomy. The left bronchus was transsected and reanastomosed. In the control group (n = 6), the bronchial arteries were preserved and in the study group (n = 6) they were severed. Bronchial mucosa blood flow (BMBF) was measured with laser-Doppler velocimetry and bronchial mucosa haemoglobin saturation and concentration with diffuse reflectance spectrophotometry. Measurements were made preoperatively, postoperatively and after 1 week. RESULTS: In the study group, left postoperative BMBF was significantly lower than preoperatively (115 vs. 210 PU/s, p = 0.0001) and lower than in the control group (115 vs. 205 PU/s, p = 0.002). Repeated measurement ANOVA showed a significant treatment effect depending on time (p = 0.0034). The left mucosal haemoglobin saturation in the study group was significantly reduced postoperatively, 92% versus 61%, with a treatment effect depending on time (p = 0.0080). The reduction in left/right ratio of the mucosal haemoglobin concentration 1 week postoperatively in the study group was insignificant. CONCLUSION: Bronchial transsection and reanastomosis without bronchial artery blood supply was followed by significant decrease in mucosal blood flow and saturation postoperatively, and also in tissue haemoglobin concentration at section, and provides a physiologic explanation of histological changes.

[A 10-kg ovarian mucinous cystadenoma in a 13 year-old girl]. / Ti-kilo-ovariecyste hos 13-årig.

A 13 year-old girl was admitted to hospital with abdominal pain and weight gain. The physical examination showed pronounced abdominal distension, but slim extremities. A magnetic resonance imaging scan revealed a left cystic ovarian tumour. The ovarian tumour was removed and the weight turned out to be 10.3 kg. Pathology showed a borderline mucinous cystadenoma. Ovarian tumours represent less than 2% of all tumours in girls under the age of 16. In this age group 50% of the ovarian tumours are neoplastic and 60% derive from the surface epithelia of the ovary.

[Endoscopic complication: unsuspected impact of gastroscope into the oesophagus in a patient with a large hiatal hernia]. / Uventet komplikation ved gastroskopi hos patient med stort hiatushernie.

Gastroscopy is used world-wide and it is considered as a safe procedure. In a case study we describe an impaction of a gastroscope into the oesophagus. A gastroscopy in full narcosis was performed on a patient with a large size hiatal hernia. During the procedure the gastroscope recurved into the oesophagus. With the assistance of another gastroscope and fluoroscopic guidance the gastroscope was removed successfully. This complication may occur more often than described in literature.

[Use of skills among ambulance crews assessed by ambulance on-line record-keeping system]. / Kompetenceanvendelse hos ambulancebehandlere vurderet med ny elektronisk ambulancejournal.

INTRODUCTION: To fulfil the increasing requirements for documentation and quality assurance, amPHI, an ambulance on-line record-keeping system has been developed. We present the data from the pilot study to access how often ambulance crews use their skills. MATERIALS AND METHODS: As a pilot study amPHI was installed and tested in an emergency ambulance for 21 months. Data was entered using a computer with touch-enabled screen. Communication between the ambulance and the hospital was established through a special secured network based on the GSM mobile telephone network. RESULTS: The ambulance was dispatched for 830 high-priority services and amPHI was used in 674 cases (81%) during the pilot study. A total of 26 out of 31 skills were used less than ten times a year per EMT (Emergency Medical Technician). Three of these skills--mask-ventilation, CPR (Cardio Pulmonary Resuscitation) and suction are technically difficult and require routine. CONCLUSION: The initial treatment is of prime importance for the outcome of the patient. It is therefore necessary to ensure that the ambulance crew is able to maintain their skills. In this connection amPHI can be very useful. Important and sometimes life-saving skills such as mask-ventilation, CPR and suction were used to a very limited extent. It is of great importance for the EMT to keep up these skills in another way. The ambulance crews are satisfied with the amPHI system and find it easy to use.

Diffuse reflectance spectrophotometry with visible light: comparison of four different methods in a tissue phantom.

The purpose of the study was to compare algorithms of four methods (plus two modifications) for spectrophotometric haemoglobin saturation measurements. Comparison was made in tissue phantoms basically consisting of a phosphate buffer, Intralipid and blood, allowing samples to be taken for reference measurements. Three experimental series were made. In experiment A (eight phantoms) we used the Knoefel method and measured specific extinction coefficients with a reflection spectrophotometer. In experiment B (six phantoms) the fully oxygenated phantoms were gradually deoxygenated with baker's yeast, and simultaneous measurements were made with our spectrophotometer and with a reference oxymeter (ABL-605) in 3 min intervals. For each spectrophotometric measurement haemoglobin saturation was calculated with all algorithms and modifications, and compared with reference. In experiment C (11 phantoms) we evaluated the ability of a modification of the Knoefel method to measure haemoglobin concentration in absolute quantities using extinction coefficients from experiment A.Results. Experiment A: with the Knoefel method extinction coefficients (+/-SD) for oxyhaemoglobin at 553.04 and 573.75 nm were 1.117 (+/-0.0396) ODmM(-1) and 1.680 (+/- 0.0815) ODmM(-1), respectively, and for deoxyhaemoglobin 1.205 (+/- 0.0514) ODmM(-1) and 0.953 (+/-0.0487) ODmM(-1), respectively. Experiment B: high correlation with the reference was found in all methods (r = 0.94-0.97). However, agreement varied from evidently wrong in method 3 and the original method 4 (e.g. saturation above 160%) to high agreement in method 2 as well as the modifications of methods 1 and 4, where oxygen dissociation curves were close to the reference method. Experiment C: with the modified Knoefel method the mean haemoglobin concentration difference from reference was 8.3% and the correlation was high (r = 0.91). We conclude that method 2 and the modifications of 1 and 4 were superior to the others, but depended on known values in the same or similar phantoms. The original method 1 was independent of results from the tissue phantoms, but agreement was slightly poorer. Method 3 and the original method 4 could not be recommended. The ability of the modified method 1 to measure haemoglobin concentration is promising, but needs further development.

Multi-centre comparison of five eye movement detection algorithms.

Although various investigators have suggested algorithms for the automatic detection of eye movements during sleep, objective comparisons of the proposed methods have previously been difficult due to different recording arrangements of different investigators. In this study the results of five eye movement detection algorithms applied to the same data were compared to visually scored data. The percentages of true and false detections are given for various threshold levels in rapid and slow eye movement detections. The methods gave best results when they were used with the same electrode montage they were designed for but the performance decreased when other montages were used. Subtracting the cross-talk of EEG delta activity improved the correctness of eye movement detections.