Monitoring technologies in the neonatal intensive care unit: implications for the detection of necrotizing enterocolitis

Necrotizing enterocolitis is the most common and fulminant gastrointestinal disease affecting neonates. Its pathogenesis is heterogeneous and not clearly understood. Early detection could prevent some of the devastating consequences of this disease, but currently there is no noninvasive method of reliable early-stage detection. Here, we review various noninvasive monitoring technologies that have already been employed or show promise for early detection. Each method may have an important role after its technical difficulties are resolved. These are discussed in detail as they relate to various aspects of the putative pathophysiology of this devastating disease.

[Manipulative treatment of the cervical spine and stroke]

Manipulative therapy of the cervical spine is associated with a considerable risk of stroke. We evaluated all cases with the diagnosis of arterial dissection submitted between 1996 and 2005 to the Schlichtungsstelle für Arzthaftpflichtfragen der Norddeutschen Arztekammern for assessment of the accusations brought against the therapists who conducted the manipulation. Neither in the 7 carotid nor in the 9 vertebral artery cases could a causal link be made between the dissection and the manipulation. However, in 5 of the 7 carotid and 7 of the 9 vertebral artery dissections there was clear evidence or high probability that the dissection was present prior to the manipulation, and had caused neck pain, segmental dysfunction and, in some cases, even neurological symptoms. Stroke after manipulative therapy was due to embolisation of thrombotic material from the dissected artery. As both cervical arterial dissection and cervical spine disorder usually cause similar signs and symptoms physicians must differentiate between these two entities prior to any manipulative therapy. Clinical indicators of pre-existent dissection and the medicolegal implications are discussed in this paper.

[Malpractice in the diagnosis and treatment of the slipped capital femoral epiphysis]

INTRODUCTION

Expert commissions (Gutachterkommissionen) and arbitration offices (Schlichtungsstellen) in Germany are expert panels for the extrajudical resolution of malpractice claims. The performance of arbitration panel proceedings ("Schlichtungsverfahren") is based on the German medical and insurance jurisdiction.

METHOD

39 arbitration panel proceedings concerning supposed malpractice in the diagnosis and treatment of slipped capital femoral epiphysis were evaluated in regard to the involved clinics and physicians and, respectively, the medical specialties, type of slippage (acute or chronic), malpractice and the disabilities caused by malpractice.

RESULTS

In 28 cases (72 %) the malpractice was confirmed, the average of confirmed failures in all proceedings being about 30 %. The failures could be classified as misdiagnosis followed by inadequate treatment and failures in operative treatment. Minor and moderate permanent disabilities due to malpractice remained in 8 cases, severe permanent disability resulted in 14 cases due to osteonecrosis of the femoral head.

DISCUSSION

The results are discussed with regard to the avoidance of mistakes in diagnosis and treatment and the problems of medical assessment.

[Injuries in anaesthesia. Results of the Hannover arbitration procedure 2001-2005]

The Schlichtungsstelle in Hannover (expert panel for arbitration), northern Germany, was founded in 1976 to settle disputes between patients and doctors. Furthermore, publications regarding the decisions of the Schlichtungsstelle serve as an important medium to prevent malpractice by increasing doctors' awareness of critical processes in their field. Between 2001 and 2005 the Schlichtungsstelle decided on 435 malpractice claims in anaesthesia. An accumulation of injuries was observed in anaesthetic procedures with respect to the airways (23.9%), injuries related to regional anaesthesia (18.2%), vasopuncture (13.1%) and positioning of the patients (9.9%). In 21.8%, the Schlichtungsstelle advised to seek a resolution without going to court by paying financial compensation in favour of the patient. In these cases the Schlichtungsstelle's evaluation had come to the conclusion that malpractice was the cause of the patient's injury. We would like to mention that 21 cases of intraoperative awareness were included in the claims, of which 52.4% (average 21.8%) were evaluated to be the result of malpractice and thus financial compensation was advised. The appropriate care for the patient, required from every doctor, calls the anaesthesiologists to avoid all possible malpractices, thus reducing patients' injury due to such malpractices to a minimum. But even injuries not caused by malpractice need to be examined closely and improvement should be sought.

[Evaluation of 157 arbitration procedures against maxillofacial surgeons handled by the arbitration office of the North German Medical Associations from 2000 to 2005]

Medical work is, just like any other profession, not always without error and even when no mistake has been made the patient may suffer health damages, because such are the unavoidable risks. Arbitration procedures of medical liability disputes can in particular cases resolve the individual conflict between physician and patient. The results of these arbitration procedures can point towards the main focus of diagnosis, patient accusations (patient dissatisfaction) and treatment errors. In the space of 6 years from 2000 until 2005 the North-German arbitration office handled 157 arbitration procedures against Maxillofacial surgeons. The decisions were statistically and casuistically analysed with regard to patient accusations, type of treatment error, frequency of treatment error, health damages that were caused and not caused by errors. Liability claims against a physician result only from those errors that have caused health damages to a patient. Not all errors cause damage automatically. Patient claims were found to be justified in 28% of all procedures and a recommendation for regulation was made to the physician's insurance. Maxillofacial surgery, with reference to the 20.4% of cases analysed, clearly represents less than the total average. The main focus of accusations raised by patients and also the main focus of the observed treatment errors are operative errors as a cause of sensitivity defects of the lower lip and the tongue, also of tongue damages and their associated taste defects. Parallel to the 20.4% of cases, which showed iatrogenic health damages caused by errors, 60.9% of cases showed patients had also suffered iatrogenic damages even though no medical errors had caused them.

NICHD: AAP workshop on neonatology research and training areas of research in neonatal gastroenterology

Future research in neonatal and developmental gastroenterology should include inquiry well beyond finding a cure or better preventative measures against necrotizing enterocolitis. The gastrointestinal (GI) tract acts not only as a digestive-absorptive organ; it also serves major endocrine and neural functions. It encompasses a vast surface area exposed to the external environment and plays a major role in both innate and adaptive immunity. Numerous short- and long-term health benefits could be derived from a better understanding of the developing GI tract.

Tight junctions, leaky intestines, and pediatric diseases

BACKGROUND

Tight junctions (TJs) represent the major barrier within the paracellular pathway between intestinal epithelial cells. Disruption of TJs leads to intestinal hyperpermeability (the so-called "leaky gut") and is implicated in the pathogenesis of several acute and chronic pediatric disease entities that are likely to have their origin during infancy.

AIM

This review provides an overview of evidence for the role of TJ breakdown in diseases such as systemic inflammatory response syndrome (SIRS), inflammatory bowel disease, type 1 diabetes, allergies, asthma, and autism.

CONCLUSION

A better basic understanding of this structure might lead to prevention or treatment of these diseases using nutritional or other means.

The role of intraoperative digital subtraction angiography for quality control of standard carotid endarterectomy using patch angioplasty

The absence of technical defects is considered to be of great importance during carotid endarterectomy (CEA). In this context, both safe surgical technique and intraoperative quality control may be a fundamental part of the operative procedure. We have therefore undertaken a prospective study to evaluate the possible benefits of completion angiography in standard CEA using patch angioplasty. The objectives were three-fold: (1) to identify the incidence of defects requiring prompt revision; (2) to assess the perioperative stroke rate as well as the number of residual stenosis after 6 weeks in angiographically controlled patients and (3) to compare these results with a control group. From 1 January to 30 September 1999 111 patients with 115 consecutive CEAs which had completion angiography (Group A) were prospectively entered into this study. The results in group A were compared with a series of again 111 patients (Group B) which had 116 CEAs without intraoperative quality control between January and September in the year before. Surgical technique was identical in both groups. In general, risk factors were distributed evenly among both group with the exception that in group A were significantly more high-grade ipsilateral ICA stenoses while group B had more patients with diabetes and ipsilateral CT-defects. In group A, angiographic irregularities prompted us to immediate re-exploration in five patients (dilatation of severe ICA spasm 1; re-exploration of distal ICA occlusion 1; reopening of occluded ECA 3). With a 30 day mortality of 0% each perioperative stroke rate was comparable with 3/115 in group A and 3/116 in group B (P=1.0). 2/3 patients with neurological deficits in group A had early postoperative carotid thrombosis--in spite of a normal completion study. Duplex examination after 6 weeks revealed one asymptomatic ICA occlusion in each group. The incidence of residual stenosis (> or =50%) was not significantly different being 3.7% in group A and 3.2% in group B (P=0.85). When applying a safe and simple operative technique for CEA, the incidence of abnormalities warranting immediate correction appears to be a rare event and, therefore, the necessity for obligatory quality control may be questionable. On the other hand, completion DSA allows a simple documentation of the adequacy of the surgical procedure.

Glutamine in the fetus and critically ill low birth weight neonate: metabolism and mechanism of action

Of all the amino acids, glutamine is the most versatile. Studies in the maternal-fetal-placental unit demonstrate that both glutamine and glutamate play an important role in fetal and placental metabolism. If an infant is born very prematurely, the supply of glutamine from the mother is suddenly interrupted. The infant is dependent on endogenous synthesis or an exogenous supply of glutamine to meet the challenges of the external environment and a tripling of body weight in the first 3-4 mo of life. Studies of glutamine supplementation in low birth weight infants and critically ill adults suggest benefits, especially in terms of decreased nosocomial infections. Two large multicenter trials are currently underway that are designed to address these potential benefits in very low birth weight infants. These trials will not explain the mechanism of action. This review raises hypotheses about the role of the amide nitrogen of glutamine for nucleotide and glucosamine synthesis in the small intestine and how this might relate to greater integrity of the intestinal mucosa, hence preventing bacterial translocation and/or the subsequent proinflammatory response that might lead to multiorgan failure.

Effect of protein shape on multibody interactions between membrane inclusions

The elastic interaction of membrane inclusions provides one of the simplest physical realizations of multibody forces. Here we show how the cross-sectional shape of the inclusion greatly changes the character of the interaction, and illustrates a pattern formation mechanism. The formalism provides a transparent framework for modeling bilayer-inclusion boundary effects on the multibody interaction.

Glutamine supplementation in low-birth-weight infants: mechanisms of action

Very low-birth-weight infants have minimal endogenous nutritional reserves and are at high risk for stresses that induce further breakdown of these diminished reserves. They frequently receive very little glutamine because enteral feedings are often delayed and glutamine is not included in parenteral nutrition. Here we describe studies of glutamine supplementation in very low-birth-weight infants and discuss potential mechanisms for the beneficial effects.

Necrotizing enterocolitis: pathophysiology and prevention

Necrotizing enterocolitis (NEC) is the most common gastrointestinal emergency in the neonatal intensive care unit. It is a disease of medical progress in that more very low-birth-weight neonates are surviving than ever before and are thus susceptible to this potentially devastating disease. NEC received very little attention in the literature before the 1970s but now is well known to all neonatologists and pediatric surgeons. The 1500 to 2000 infants that die every year from this disease in the United States and the large number of infants who develop short gut syndrome from this disease only represent the tip of the iceberg of the problems NEC causes. The widespread fear of NEC among neonatologists and pediatric surgeons has contributed in large part to the use of the IV route rather than the gastrointestinal tract for nourishing these infants for relatively long periods. The consequences of this include a high incidence of sepsis, high hospital costs, and potential long-term neurodevelopmental disability because of poor nutrition during a very vulnerable period of growth and development. The purpose of this review is to provide a brief overview of the clinical presentation and current treatment for NEC, then provide a discussion of the pathophysiology on which strategies for prevention can be formulated.

Glutamine synthetase: a key enzyme for intestinal epithelial differentiation?

BACKGROUND

We have previously shown that glutamine synthetase protein and mRNA are concentrated in the crypt region of the rat small intestine and that the activity of this enzyme is highest around the time of weaning. This anatomical location and time of peak activity are sites and periods of active enterocyte differentiation. This led to our current hypothesis that glutamine synthetase is important in the differentiation of enterocytes.

METHODS

To test our hypothesis, we treated Caco-2 cells with physiologic (0.6 mM) glutamine concentrations in cell culture medium. The experimental group was treated with methionine sulfoximine, an irreversible glutamine synthetase inhibitor, and the control group with phosphate buffered saline. Three standard and well-defined markers of intestinal differentiation-sucrase-isomaltase activity, microvillus formation, and electrical impedance in transwell plates-were compared between the two groups.

RESULTS

The methionine-sulfoximine-inhibited group was found to have lower sucrase-isomaltase activity, a lower density of microvilli, and lower electrical impedance values over time compared with the control group.

CONCLUSION

The experimental group was found to be less differentiated by all three markers of differentiation. Therefore, glutamine synthetase is important for Caco-2 cell differentiation.