Prediction of outcome from intensive care after gastroenterologic emergency

Prognostic factors determining the outcome from intensive care were studied in 952 patients admitted to 25 Finnish ICUs after gastroenterologic emergency. Logistic regression analysis was used to create predictive models based on the APACHE II–system. The models were constructed by using data from a random two–thirds of the study population and validated in the remaining independent one–third together with the original APACHE II–index. The Acute Physiology Score, age, and a pre–existing liver disease were the three most important determinants of outcome. The inclusion of the TISS score describing the intensity of treatment into a model did not enhance the accuracy of the prediction. Our models were better calibrated than the original APACHE II–equation when tested by the goodness–of–fit –statistics. These statistical models may help the clinicians to predict the outcome for an individual patient by providing them information about the relative impacts of predictive factors or about the probability of death. These probabilities should be interpreted cautiously, taking into acount the limitations of statistical methods. This is especially important when assessing the highrisk patients. Their number in our study was too low for accurate outcome prediction.     

Continuous positive airway pressure by mask in patients after coronary surgery

Thirty patients who underwent coronary artery bypass grafting were randomized to receive 30% oxygen by mask either with an ambient airway pressure or with 7.4 mmHg (1 kPa) continuous positive airway pressure (CPAP) for 8 h after extubation. Arterial blood oxygen tension (Pao₂) decreased remarkably in the control group after extubation (from 19.2± 5.3 kPa to 12.4 ± 2.7 kPa) but less in the CPAP group (from 16.4 ± 3.3 kPa to 14.0 ± 2.1 kPa). On the second postoperative morning Pao₂ was equally low in both groups (control: 8.4 ± 1.5 kPa, CPAP: 8.9 ± 1.9 kPa). Atelectatic areas were seen with similar frequency in both groups, 17% (whole material) on the first and 50% on the second postoperative morning. Atelectasis was more common in patients with internal thoracic artery grafting and/or pleural drainage. In conclusion, CPAP therapy was well tolerated, and minimized the decrease in Pao₂ after extubation, but could not prevent the poor oxygenation or the late development of atelectatic areas on the second postoperative day.     

Structural studies by H NMR of a prototypic α-helical peptide (LYQELQKLTQTLK) and homologs in trifluoroethanol/water and on sodium dodecyl sulfate micelles

The H NMR-determined structure and dynamics of a synthetic, amphiphilic α-helical peptide, PH-1.0 (LYQELQKLTQTLK), and several homologs were compared in 50% trifluoroethanol-d₂ (TFE-d₂)/H₂O and in sodium dodecyW₂₅ sulfate (SDS-d₂₅) micelles. The peptides were designed to test the influence on secondary structure of placement of favored and disfavored residues relative to a “longitudinal, hydrophobic strip-of-helix” defined by the repeating leucines. PH-1.0 was highly ordered as an α-helix in 50% TFE-d₂/H₂O and in SDS-d₂₅ micelles. Homologs PH-1.1, in which LI was replaced by T, and PH-1.4, in which LI 2 was replaced by T, were found to be partially helical in both media. Calculated structures in SDS-d₂₅ revealed that the helix of PH-1.1 was slightly disordered at the N-terminus, but that of PH-1.4 was completely disordered at the C-terminus. Examination of distributions of hydrophobic residues in protein structures revealed that, when ?= LIVFM and ?= nonLIVFM, the pattern ????? is favored and ????? is disfavored in α-helices. Several analogs of PH-1.0 incorporating these patterns were studied. Peptide PH-1.12 (L YQEL QKL L QTL K) retained a-helical structure in both 50% TFE-d₂/H₂O and in SDS-d₂₅ micelles. However, although PH-1.13 (L YQEL QKL L QTL K) was fully helical in 50% TFE, it was helical only through residue 6 in SDS micelles. Two homologs containing an additional loop of the helix and repeats of favored (PH-5.0, NYL QTL L ETL KTL L QK) or suppressed LL patterns (PH-5.11, NYL QTL EL TL KL TL QK) gave similar results, i.e. the latter peptide was helical only through residue 6 in SDS micelles. The degree of local order in these SDS micelle-adsorbed peptides correlates to placement of hydrophobic residues in motifs which are favored or disfavored in proteins in general and in α-helices specifically. © Munksgaard 1997.     

High-performance Thin-layer Chromatography for the Determination of Nimesulide in Human Plasma,and its Use in Pharmacokinetic Studies

A rapid and sensitive high-performance thin-layer chromatographic assay has been developed for the measurement of nimesulide in human plasma. Its use for pharmacokinetic studies has been evaluated. The method includes a single-stage extraction procedure without the use of an internal standard. Analysis was performed on plasma containing known amounts of the drug, on drug-free plasma, and on plasma containing an unknown quantity of the drug. Known amounts of extract and nimesulide (100 and 200 ng, as external standard) were spotted on precoated silica-gel 60F₂₅₄ plates by means of a Camag Linomat IV autosampler. Quantification was achieved using a Camag TLC scanner 3. The recovery of the method was 97.10 ± 2.22%. The method was applied for the determination of plasma levels and pharmacokinetic parameters of nimesulide after oral administration of two formulations (100 mg) in healthy volunteers. The method is a sensitive, economical, rapid and specific assay for nimesulide in human plasma, and is suitable for pharmacokinetic studies after therapeutic doses.     

Anaesthesia for carotid body tumour resection

Anaesthetic management is described for the resection of a non-secreting carotid body tumour in a woman who had previously had a pneumonectomy. A brief review of the literature includes mention of some of the complications associated with the resection of carotid body tomours.     

Characteristics of Ischemic and Peri-Ischemic Regions During Ventricular Fibrillation in the Canine Heart

INTRODUCTION: Although premature beats originating in areas of ischemia have been shown to be important in initiating ventricular fibrillation (VF), the participation of the ischemic zone in maintenance of VF has not been investigated. METHODS AND RESULTS: Ten normal dogs underwent induction of two separate episodes of VF, before and 10 minutes after left anterior descending coronary artery ligation. Ischemic VF was allowed to occur spontaneously or was induced by burst pacing after 10 minutes of ischemia. Unipolar epicardial electrograms were recorded using an 8 x 14 plaque electrode array (interelectrode distance 2.5 mm) placed over the anterior wall. Activation during VF was characterized by VF cycle length (CL) and wavefront organization based on linking analysis of epicardial activation directions at adjacent sites. Individual plaque sites were separated into regions based on electrogram morphology during ischemia: R1 = no ischemia; R2 = mild-to-moderate ischemia (minor ST elevation and QRS widening); and R3 = severe ischemia (marked ST elevation and QRS widening). Percent conduction block was calculated based on the percent of cycles during which sites were not activated during VF. There were no significant differences noted in mean CL or mean percent conduction block in the peri-ischemic region R1 compared to the same region under nonischemic (control) conditions. During ischemia, the mean CL was noted to increase in R2 from 111+/-14 msec (control) to 128+/-29 msec (ischemia) and in R3 from 113+/-14 msec (control) to 150+/-42 msec (ischemia) (P < 0.05). The percentage conduction block in R2 increased from 6%+/-11% (control) to 14%+/-16% (ischemia) and in R3 from 4%+/-6% (control) to 44%+/-21% (ischemia) (P < 0.05). Linking analysis revealed no significant changes in VF organization at distances of 2.5 mm in regions R1 and R2 under both control and ischemic conditions. Premature beats initiating fibrillation originated at the border between the normal and mildly ischemic zones. CONCLUSIONS: (1) Some VF characteristics are altered in ischemic regions including a longer VFCL and greater percentage of functional block. (2) VF characteristics are unchanged in immediately adjacent nonischemic myocardium. (3) Although the ischemic zone may be involved in the initiation of VF and has unique activation characteristics during VF, it does not affect VF characteristics in the adjacent nonischemic zone, suggesting that it may not play a major role in VF maintenance.     

A clinico‐radiological phenotype of voltage‐gated potassium channel complex antibody‐mediated disorder presenting with seizures and basal ganglia changes

In childhood, central nervous system (CNS) presentations associated with antibodies to voltage‐gated potassium channel (VGKC) complex include limbic encephalitis, status epilepticus, epileptic encephalopathy, and autistic regression. We report the cases of two individuals (a 6‐year‐old male and an 11‐year‐old female) who presented with an acute‐onset explosive seizure disorder with positive VGKC complex antibodies and bilateral basal ganglia changes on magnetic resonance imaging (MRI). Both patients made a complete clinical recovery, without immunotherapy, with resolution of the MRI changes and normalization of the antibody levels. Extended antibody testing, including testing for leucine‐rich glioma‐inactivated 1 (LGI1), contactin‐associated protein 2, and contactin‐2 was negative. This could suggest that the clinico‐radiological phenotype in our patients may in fact be associated with a novel autoreactive target(s) within the VGKC complex, as may be the case in other children with VGKC complex‐mediated CNS disorders.     

Small cell neuroendocrine carcinoma of the rectum associated with chronic ulcerative colitis

A case of small cell carcinoma of the rectum in a patient with chronic ulcerative colitis is described. There was no evidence of enteroendocrine cell hyperplasia.