Exploring scenarios for the food system-zoonotic risk interface

The unprecedented economic and health impacts of the COVID-19 pandemic have shown the global necessity of mitigating the underlying drivers of zoonotic spillover events, which occur at the human-wildlife and domesticated animal interface. Spillover events are associated to varying degrees with high habitat fragmentation, biodiversity loss through land use change, high livestock densities, agricultural inputs, and wildlife hunting-all facets of food systems. As such, the structure and characteristics of food systems can be considered key determinants of modern pandemic risks. This means that emerging infectious diseases should be more explicitly addressed in the discourse of food systems to mitigate the likelihood and impacts of spillover events. Here, we adopt a scenario framework to highlight the many connections among food systems, zoonotic diseases, and sustainability. We identify two overarching dimensions: the extent of land use for food production and the agricultural practices employed that shape four archetypal food systems, each with a distinct risk profile with respect to zoonotic spillovers and differing dimensions of sustainability. Prophylactic measures to curb the emergence of zoonotic diseases are therefore closely linked to diets and food policies. Future research directions should explore more closely how they impact the risk of spillover events.

Health and environmental impacts of plant-rich dietary patterns: a US prospective cohort study

BACKGROUND

Diets that are rich in animal-based foods threaten planetary and human health, but plant-rich diets have varied health and environmental effects. We aimed to characterise a healthy dietary index and three plant-based indices by their environmental impacts and associations with risk of cardiovascular disease.

METHODS

In this prospective cohort study, we used data from a food-frequency questionnaire in the US-based Nurses' Health Study II. Participants were categorised by quintiles of four dietary indices, including the alternative healthy eating index-2010 (AHEI), plant-based diet index (PDI), unhealthy PDI, and healthy PDI. We calculated environmental impacts (greenhouse gas emissions and irrigation water, nitrogenous fertiliser, and high-quality cropland needs), and relative risks (RRs) of cardiovascular disease from 1991-2017, comparing quintiles.

FINDINGS

We included 90 884 participants in the health-impact analysis and 65 625 participants in the environmental-impact analysis. Comparing the top and bottom quintiles, higher AHEI scores were associated with a decreased cardiovascular disease risk (relative risk 0·77 [95% CI 0·66-0·89]); 30% lower greenhouse gas emissions (Q5 2·6 kg CO₂ equivalent vs Q1 3·7 kg CO₂ equivalent); and lower fertiliser, cropland, and water needs (all p_trends<0·0001). Similarly, the highest healthy PDI and PDI quintiles were associated with a decreased cardiovascular disease risk (healthy PDI 0·71 [0·60-0·83] and PDI 0·74 [0·63-0·85]) and lower environmental impacts (PDI water needs p_trend=0·0014; all other p_trends<0·0001). Conversely, the highest unhealthy PDI quintile had a higher cardiovascular disease risk compared with the lowest unhealthy PDI quintile (1·15 [1·00-1·33]; p_trend=0·023) and required more cropland (p_trend<0·0001) and fertiliser (p_trend=0·0008).

INTERPRETATION

Dietary patterns that are associated with better health had lower greenhouse gas emissions and nitrogenous fertiliser, cropland, and irrigation water needs. Not all plant-based diets conferred the same health and environmental benefits. US dietary guidelines should include nuanced consideration of environmental sustainability.

FUNDING

US National Institutes of Health.

Environmental performance of blue foods

Fish and other aquatic foods (blue foods) present an opportunity for more sustainable diets^1,2. Yet comprehensive comparison has been limited due to sparse inclusion of blue foods in environmental impact studies^3,4 relative to the vast diversity of production⁵. Here we provide standardized estimates of greenhouse gas, nitrogen, phosphorus, freshwater and land stressors for species groups covering nearly three quarters of global production. We find that across all blue foods, farmed bivalves and seaweeds generate the lowest stressors. Capture fisheries predominantly generate greenhouse gas emissions, with small pelagic fishes generating lower emissions than all fed aquaculture, but flatfish and crustaceans generating the highest. Among farmed finfish and crustaceans, silver and bighead carps have the lowest greenhouse gas, nitrogen and phosphorus emissions, but highest water use, while farmed salmon and trout use the least land and water. Finally, we model intervention scenarios and find improving feed conversion ratios reduces stressors across all fed groups, increasing fish yield reduces land and water use by up to half, and optimizing gears reduces capture fishery emissions by more than half for some groups. Collectively, our analysis identifies high-performing blue foods, highlights opportunities to improve environmental performance, advances data-poor environmental assessments, and informs sustainable diets.

Reorientation of aquaculture production systems can reduce environmental impacts and improve nutrition security in Bangladesh

Aquatic foods are a critical source of human nutrition in many developing countries. As a result, declines in wild-caught fish landings threaten nutritionally vulnerable populations. Aquaculture presents an opportunity to meet local demand, but it also places pressure on natural resource inputs and causes a range of environmental impacts. Here, we examine whether current aquaculture systems in Bangladesh can be reoriented to address prevailing nutritional deficiencies while minimizing these environmental impacts. Current fish farming practices, even when optimized, cannot fully supply the same essential micronutrient densities of zinc, iron and calcium as wild-caught fish. However, when the proportion of highly nutrient-dense small indigenous fish species (SIS) was increased to at least 30% of the total output in any of the 14 aquaculture production systems analysed, these systems were able to meet or surpass the nutrient densities of average wild-capture fisheries. Extensive aquaculture systems that co-produce fish and rice had the lowest environmental burdens in six out of seven metrics examined when the composition of all aquaculture systems was modified to include 50% SIS. Nutrition-sensitive aquaculture that provides greater human health benefits and minimizes environmental impacts is a key societal challenge that requires targeted interventions and supportive policies.

Environmentally Optimal, Nutritionally Sound, Protein and Energy Conserving Plant Based Alternatives to U.S. Meat

Because meat is more resource intensive than vegetal protein sources, replacing it with efficient plant alternatives is potentially desirable, provided these alternatives prove nutritionally sound. We show that protein conserving plant alternatives to meat that rigorously satisfy key nutritional constraints while minimizing cropland, nitrogen fertilizer (Nr) and water use and greenhouse gas (GHG) emissions exist, and could improve public health. We develop a new methodology for identifying nutritional constraints whose satisfaction by plant eaters is challenging, disproportionately shaping the optimal diets, singling out energy, mass, monounsaturated fatty acids, vitamins B_3,6,12 and D, choline, zinc, and selenium. By replacing meat with the devised plant alternatives—dominated by tofu, soybeans, peanuts, and lentils—Americans can collectively eliminate pastureland use while saving 35–50% of their diet related needs for cropland, Nr, and GHG emission, but increase their diet related irrigation needs by 15%. While widely replacing meat with plants is logistically and culturally challenging, few competing options offer comparable multidimensional resource use reduction.

A model for 'sustainable' US beef production

Food production dominates land, water and fertilizer use and is a greenhouse gas source. In the United States, beef production is the main agricultural resource user overall, as well as per kcal or g of protein. Here, we offer a possible, non-unique, definition of 'sustainable' beef as that subsisting exclusively on grass and by-products, and quantify its expected US production as a function of pastureland use. Assuming today's pastureland characteristics, all of the pastureland that US beef currently use can sustainably deliver ≈45% of current production. Rewilding this pastureland's less productive half (≈135 million ha) can still deliver ≈43% of current beef production. In all considered scenarios, the ≈32 million ha of high-quality cropland that beef currently use are reallocated for plant-based food production. These plant items deliver 2- to 20-fold more calories and protein than the replaced beef and increase the delivery of protective nutrients, but deliver no B₁₂. Increased deployment of rapid rotational grazing or grassland multi-purposing may increase beef production capacity.

Expanded view of ecosystem stability: A grazed grassland case study

Analysis of stability under linearized dynamics is central to ecology. We highlight two key limitations of the widely used traditional analysis. First, we note that while stability at fixed points is often the focus, ecological systems may spend less time near fixed points, and more time responding to stochastic environmental forcing by exhibiting wide zero-mean fluctuations about those states. If non-steady, uniquely precarious states along the nonlinear flow are analyzed instead of fixed points, transient growth is possible and indeed common for ecosystems with stable attractive fixed points. Second, we show that in either steady or non-steady states, eigenvalue based analysis can misleadingly suggest stability while eigenvector geometry arising from the non-self-adjointness of the linearized operator can yield large finite-time instabilities. We offer a simple alternative to eigenvalue based stability analysis that naturally and straightforwardly overcome these limitations.

Environmentally Optimal, Nutritionally Aware Beef Replacement Plant-Based Diets

Livestock farming incurs large and varied environmental burdens, dominated by beef. Replacing beef with resource efficient alternatives is thus potentially beneficial, but may conflict with nutritional considerations. Here we show that protein-equivalent plant based alternatives to the beef portion of the mean American diet are readily devisible, and offer mostly improved nutritional profile considering the full lipid profile, key vitamins, minerals, and micronutrients. We then show that replacement diets require on average only 10% of land, 4% of greenhouse gas (GHG) emissions, and 6% of reactive nitrogen (Nr) compared to what the replaced beef diet requires. Applied to 320 million Americans, the beef-to-plant shift can save 91 million cropland acres (and 770 million rangeland acres), 278 million metric ton CO2e, and 3.7 million metric ton Nr annually. These nationwide savings are 27%, 4%, and 32% of the respective national environmental burdens.

Land, irrigation water, greenhouse gas, and reactive nitrogen burdens of meat, eggs, and dairy production in the United States

Livestock production impacts air and water quality, ocean health, and greenhouse gas (GHG) emissions on regional to global scales and it is the largest use of land globally. Quantifying the environmental impacts of the various livestock categories, mostly arising from feed production, is thus a grand challenge of sustainability science. Here, we quantify land, irrigation water, and reactive nitrogen (Nr) impacts due to feed production, and recast published full life cycle GHG emission estimates, for each of the major animal-based categories in the US diet. Our calculations reveal that the environmental costs per consumed calorie of dairy, poultry, pork, and eggs are mutually comparable (to within a factor of 2), but strikingly lower than the impacts of beef. Beef production requires 28, 11, 5, and 6 times more land, irrigation water, GHG, and Nr, respectively, than the average of the other livestock categories. Preliminary analysis of three staple plant foods shows two- to sixfold lower land, GHG, and Nr requirements than those of the nonbeef animal-derived calories, whereas irrigation requirements are comparable. Our analysis is based on the best data currently available, but follow-up studies are necessary to improve parameter estimates and fill remaining knowledge gaps. Data imperfections notwithstanding, the key conclusion--that beef production demands about 1 order of magnitude more resources than alternative livestock categories--is robust under existing uncertainties. The study thus elucidates the multiple environmental benefits of potential, easy-to-implement dietary changes, and highlights the uniquely high resource demands of beef.

"Alice in wonderland" syndrome: a manifestation of infectious mononucleosis in children

The association between "Alice in Wonderland" Syndrome (AWS) and infectious mononucleosis (IM) has been previously described in three patients.We describe two additional cases in children, where in one case, the visual symptoms of AWS appeared during the course of active IM and in the second, 2 weeks following a clinically mild, but serologically proven attack.

A geophysical foundation for alternative farm policy

An optimization method could aid agricultural decision making by balancing societal desire(s) with resource management.

Bicycle-related injuries in children: disturbing profile of a growing problem

CONTEXT

We observed a changing pattern of bicycle-related injuries in children, with the focus changing from head trauma to thoracic and abdominal injuries, and a trend to increasingly severe injuries.

OBJECTIVE

To assess the changing injury pattern, and investigate the development of preventive measures to improve safety.

DESIGN, SETTING, AND PARTICIPANTS

Retrospective record review of 142 paediatric patients admitted to our Department of Paediatric Surgery between 1996 and 2005 following bicycle-related injuries. Clinical, laboratory, diagnostic, and therapeutic aspects were analysed. Additional information concerning children's bicycle-related injuries in Israel was obtained from the Gertner Institute (Israel National Center for Trauma and Emergency Medicine Research) and from Beterem (The National Center for Children's Safety & Health, the Safe Kids Israeli Chapter) National Report on Child Injuries in Israel 2006.

MAIN OUTCOME MEASURES

The nature and severity of injuries were reviewed, and two 5-year periods compared-from 1996 to 2000 (53 children-Group 1), and from 2001 to 2005 (89 children-Group 2).

RESULTS

Head trauma was more common in the Group 1 patients (52.6% vs. 45.2%), but skull fractures and intracranial haemorrhage occurred more frequently in Group 2 (28.5% vs. 16.7%; 21.3% vs. 8.3%, respectively). Injury to the stomach or duodenum, kidneys and liver were all more common in Group 2. Splenic injury occurred with equal frequency in both groups, but more severe injuries were seen in Group 2. More children in Group 2 required intensive care (31% vs. 19.3%).

CONCLUSIONS

There is a changing pattern of bicycle-related injuries in children, with chest and abdominal injuries dominating, and an increasing incidence of more severe injury. These findings are important in decision-making regarding preventive measures.

Urban paediatric trauma due to stab wounds: an Israeli hospital experience

OBJECTIVE

To assess the incidence and types of stab wounds to hospitalized children and adolescents.

SUBJECTS

The sample consisted of patients, age 6-18 years, who were admitted to our hospital with sustained injury between 1991 and 2007.

RESULTS

In total, 83 patients were admitted as a result of penetrating (n = 51) and superficial (n = 32) injuries. Eighty-two were hospitalized, and one was declared dead upon arrival. Only 11 patients were hospitalized during the 1991-2000 period, and 71 during the 2001-2007 period. Ten patients were admitted to the intensive care unit (ICU); 23 patients were operated (hospital mortality = 0). Evacuation time (time from injury to hospital) was 10 min (mean time; maximum 35 min).

CONCLUSION

This study found higher rates of hospitalization compared with those over a decade ago. These rates reflect not only changes in hospitalization trends and/or population growth in the hospital area but also an increase of urban violence. Israeli hospitalization system deals with paediatric trauma effectively, being well trained because of permanent terrorist activity.

Geophysics and nutritional science: toward a novel, unified paradigm

This article discusses a few basic geophysical processes, which collectively indicate that several nutritionally adverse elements of current Western diets also yield environmentally harmful food consumption patterns. We address oceanic dead zones, which are at the confluence of oceanography, aquatic chemistry, and agronomy and which are a clear environmental problem, and agriculture's effects on the surface heat budget. These exemplify the unknown, complex, and sometimes unexpected large-scale environmental effects of agriculture. We delineate the significant alignment in purpose between nutritional and environmental sciences. We identify red meat, and to a lesser extent the broader animal-based portion of the diet, as having the greatest environmental effect, with clear nutritional parallels.

Adaptations to climate in candidate genes for common metabolic disorders

Evolutionary pressures due to variation in climate play an important role in shaping phenotypic variation among and within species and have been shown to influence variation in phenotypes such as body shape and size among humans. Genes involved in energy metabolism are likely to be central to heat and cold tolerance. To test the hypothesis that climate shaped variation in metabolism genes in humans, we used a bioinformatics approach based on network theory to select 82 candidate genes for common metabolic disorders. We genotyped 873 tag SNPs in these genes in 54 worldwide populations (including the 52 in the Human Genome Diversity Project panel) and found correlations with climate variables using rank correlation analysis and a newly developed method termed Bayesian geographic analysis. In addition, we genotyped 210 carefully matched control SNPs to provide an empirical null distribution for spatial patterns of allele frequency due to population history alone. For nearly all climate variables, we found an excess of genic SNPs in the tail of the distributions of the test statistics compared to the control SNPs, implying that metabolic genes as a group show signals of spatially varying selection. Among our strongest signals were several SNPs (e.g., LEPR R109K, FABP2 A54T) that had previously been associated with phenotypes directly related to cold tolerance. Since variation in climate may be correlated with other aspects of environmental variation, it is possible that some of the signals that we detected reflect selective pressures other than climate. Nevertheless, our results are consistent with the idea that climate has been an important selective pressure acting on candidate genes for common metabolic disorders.

Pediatric Scoliosis Surgery - the association between preoperative risk factors and postoperative complications with emphasis on cerebral palsy children

Scoliosis repair surgery is a common procedure. Our study's first goal was to compare pre- and postoperative parameters between the cerebral palsy (CP) and idiopathic scoliosis (IS) children. The second goal was to establish possible associations between preoperative parameters that could predict the outcome of spinal surgery and the incidence of early postoperative complications. A retrospective record review of all children who underwent scoliosis operative surgery between 1998 and 2007 was conducted. Of the 141 children included, 21 were CP and 120 were IS. The CP children attended surgery with significantly lower weight and pulmonary reserves and had larger curves and fusions compared to the IS children. CP children had a significantly higher rate of major complications, especially pulmonary and neurological, and a higher rate of delayed extubations. In addition, young age at surgery and posterior spinal fusion correlated with a more favorable immediate postoperative prognosis among the IS population. CP children attended surgery in worse physical condition and in turn had a poorer immediate and short-term postoperative prognosis than IS children. Young age at surgery and posterior fusions revealed protective characteristics among the IS population.

Nasal midazolam as a novel anticonvulsive treatment against organophosphate-induced seizure activity in the guinea pig

Seizures and status epilepticus, which may contribute to brain injury, are common consequences of exposure to organophosphorus (OP) cholinesterase inhibitors. Effective management of these seizures is critical. To investigate the efficacy of nasal midazolam as an anticonvulsive treatment for OP exposure, as compared to intramuscular midazolam, guinea pigs were connected to a recording swivel for electrocorticograph (ECoG) monitoring and clinical observation. The experimental paradigm consisted of pyridostigmine pretreatment (0.1 mg/kg i.m.) 20 min prior to sarin exposure (1.2x LD(50,) 56 micro g/kg i.m.). One minute post-exposure, atropine (3 mg/kg i.m.) and TMB-4 (1 mg/kg im) were administered. Within 3-8 min after sarin exposure all animals developed electrographic seizure activity (EGSA), with convulsive behavior. Treatment with midazolam (1 mg/kg i.m.) 10 min after the onset of EGSA abolished EGSA within 389+/-181 s. The same dose was not effective, in most cases, when given 30 min after onset. However, a higher dose (2 mg/kg) was found efficacious after 30 min (949+/-466 s). In contrast, nasal application of midazolam (1 mg/kg) was found most effective, with significant advantages, in amelioration of EGSA and convulsive behavior, when given 10 min (216+/-185 s) or 30 min (308+/-122 s) following the onset of EGSA ( P<0.001). Thus, nasal midazolam could be used as a novel, rapid and convenient route of application against seizure activity induced by nerve agent poisoning.

Prevalence of antibodies to Chlamydia pneumoniae in an Israeli population without clinical evidence of respiratory infection

AIMS

To estimate the occurrence of recent, past, and "persistent" infections with Chlamydia pneumoniae--as indicated by serology--in an Israeli population without clinical evidence of respiratory infection.

METHODS

Serum samples from 402 subjects (172 children and 230 adults), without known respiratory symptoms, were collected. Antibodies to C pneumoniae (IgG, IgA, and IgM) were evaluated using the microimmunofluorescence (MIF) assay. Antibody prevalence and indication of recent, past, and persistent infections were calculated and their distribution determined according to age, sex, and season.

RESULTS

Antibodies to C pneumoniae were detected in 53 children (31%) and 171 adults (74%). Recent infection was indicated in only one of 50 children under 5 years of age, in nine of 122 older children, and in 19 of 230 adults. IgM antibodies were detected in nine children, but only in three adults. Past infection was indicated in six of 96 young children (aged 1-10 years), in 28 of 76 teenagers, and in 128 of 230 adults. Persistent infection was indicated in three young children, in six teenagers, and in 24 adults, with a significantly higher frequency (p = 0.012) in men (18 of 117) than in women (six of 113). No seasonal differences could be detected.

CONCLUSIONS

Infection with C pneumoniae was detected serologically in children and adults without clinical signs of respiratory disease. These results should serve as a basis for studies on the role of C pneumoniae infections and their sequelae in Israel and contribute to the general understanding of asymptomatic infection with C pneumoniae.

Snakebite poisoning in children--a call for unified clinical guidelines

In Israel, there are no uniform guidelines for the treatment policy of children snake-bitten by the Vipera palaestinae, the most abundant venomous snake in the country. We conducted a retrospective study aiming to compare treatment policies in two different medical centers. We found significant differences regarding admission and steroid administration criteria. Although the differences between the centers regarding anti-venom administration did not reach statistical significance, there were substantial differences. Neither of the centers had a well-established policy for the treatment of snake envenomation in children. In the era of cost containment, a policy of routine admission of children to the PICU service following V. palaestinae envenomation is unjustified, especially since the introduction of a specific monovalent anti-venom into the therapeutic armamentarium.

Heliox use in the treatment of acute hyperammonemia

The objective of this study was to evaluate a new method for the treatment of acute hyperammonemia with a helium-oxygen mixture (heliox). We conducted a prospective, randomized, controlled study of male Sprague-Dawley rats. Experimental hyperammonemia was induced by 7 days of a high-ammonia diet. Subsequently, the animals were randomly divided into two groups: the study group treated with heliox breathing for 24 hours and a control group breathing room air for 24 hours. A prospective, randomized, controlled laboratory animal study was conducted at an animal research facility. The baseline plasma ammonia level was 9.49 +/- 10.96 micromol/L. After 7 days of a high-ammonia diet, the plasma ammonia level rose to 31.53 +/- 8.86 micromol/L. There was a significant statistical difference between the plasma ammonia level following 24 hours of heliox therapy (23.14 +/- 13.97 micromol/L) and the ammonia level in the control group (42.31 +/- 24.25 micromol/L) (P < .05). Heliox breathing was found to be an efficient treatment modality for decreasing plasma ammonia levels in an animal model. Further studies are required to evaluate its potential application in the treatment of patients with hyperammonemia.

Peritoneal ventilation with oxygen improves outcome after hemorrhagic shock in rats

OBJECTIVE

In experimental pulmonary consolidation with hypoxemia in rabbits, peritoneal ventilation (PV) with 100% oxygen (PV-O2) improved PaO2. We hypothesized that PV-O2 could improve outcome after hemorrhagic shock (HS) with normal lungs, by mitigating dysoxia of the abdominal viscera.

DESIGN

Randomized, controlled, laboratory animal study.

SETTING

University animal research facility.

SUBJECTIVE

Male Sprague-Dawley rats.

INTERVENTIONS

Thirty rats under light anesthesia (N2O/oxygen plus halothane) and spontaneous breathing underwent blood withdrawal of 3 mL/100 g over 15 mins. After volume-controlled HS phase 1 of 60 mins, resuscitation phase 2 of 60 mins included infusion of shed blood and, if necessary, additional lactated Ringer's solution intravenously to control normotension from 60 to 120 mins. This was followed by observation phase 3 for 7 days. We randomized three groups of ten rats each: group I received PV-O2, starting at 15 mins of HS at a rate of 40 inflations/min, and a peritoneal "tidal volume" of 6 mL, until the end of phase 2. Group II received the same PV with room air (PV-Air). Control group III was treated without PV.

MEASUREMENTS AND MAIN RESULTS

During the second half of HS phase 1, mean arterial pressures were higher in the PV-O2 group I compared with the PV-Air group II and control group III (p < .05). All 30 rats survived the 120 mins of phases 1 and 2. Survival to 7 days was achieved by ten of ten rats in PV-O2 group I; by nine of ten in PV-Air group II; and by five of ten in control group III (p < .05 vs. group I; NS vs. group II). Survival times of <7 days were 5 days in the one death of group II and ranged between 6 hrs and 4 days in the five deaths of group III. In 7-day survivors, neurologic deficit scores (0% to 10% = normal, 100% = death) were normal, ranging between zero and 8%. Necropsies of rats that died during phase 3 showed multiple areas of necrosis of the gut, some with perforations. Necropsies in the five survivors to 7 days of group III showed marked macroscopic and microscopic changes (scattered areas of necrosis of stomach and intestine, adhesions, and pale areas in the liver). These changes were absent or less severe in the nine survivors of group II. Viscera appeared normal in all ten rats of PV-O2 group I.

CONCLUSIONS

Peritoneal ventilation with oxygen during and after severe hemorrhagic shock in rats seems to decrease morbidity and mortality by helping preserve viability of abdominal viscera.

[Aortopexy for tracheomalacia in infants and children]

During the past 12 years (1985-1998), 28 infants and children were operated on here for tracheomalacia. The diagnosis was made in all using rigid bronchoscopy. During the examination the infants breathed spontaneously, but the trachea collapsed on forced expiration. Indications for surgery were repeated cyanotic spells ("dying spells") in 22, recurrent pneumonia, and inability to extubate (in 8). In 11 there were more than 1 indications. Age at surgery was from 7 days to 3 years (average 11.7 months). All 28 children underwent bronchoscopy and guided aortopexy via a left-third intercostal approach. The ascending aorta and aortic arch (and in 6 the proximal innominate artery as well) were lifted anteriorly, using 3-5 non-absorbable sutures (5.0). The sutures were placed through the adventitia of the great vessels and then passed through the sternum. Respiratory distress was significantly improved in 21. Another 2 required external tracheal stenting with autologous rib grafts, and in 1 other an internal Palmaz stent was introduced for tracheal stability. In 4 aortopexy failed, 1 of whom had tracheobronchomalacia throughout, and another 3 had laryngomalacia which required tracheostomy to relieve the respiratory symptoms. Postoperative complications were minor: pericardial effusion in 1 and relaxation of the left diaphragm in another. 1 infant subsequently died, of unknown cause 10 days after operation, after having been extubated on the 1st postoperative day. On long-term follow-up (6 months to 12 years) 25 were found free of residual respiratory symptoms and 3 remained with a tracheostomy. Thus, infants and children with severe tracheomalacia associated with severe respiratory symptoms, can be relieved by bronchoscopic guided suspension of the aortic arch to the sternum.

Talismans and amulets in the Pediatric Intensive Care Unit: legendary powers in contemporary medicine

BACKGROUND

For centuries talismans and amulets have been used in many cultures for their legendary healing powers.

METHODS

We asked the parents of every child (Jews and Arabs) admitted to the Pediatric Intensive Care Unit over a 2 month period to complete a questionnaire, which included demographic data on the patient and the family, the use of talismans or other folk medicine practices, and the perception of the effects of these practices on the patient's well-being. A different questionnaire was completed by the ICU staff members on their attitude toward the use of amulets.

RESULTS

Thirty percent of the families used amulets and talismans in the ICU, irrespective of the socioeconomic status of the family or the severity of the patient's illness. Amulets and talismans were used significantly more by religious Jews, by families with a higher parental educational level, and where the hospitalized child was very young. The estimated frequency of amulet use by the children's families, as perceived by the staff, was significantly higher than actual use reported by the parents. In Jewish families the actual use of amulets was found to be 30% compared to the 60% rate estimated by the medical staff; while in Moslem families the actual use was zero compared to the staff's estimation of about 36%. Of the 19 staff members, 14 reported that the use of amulets seemed to reduce the parents' anxiety, while 2 claimed that amulet use sometimes interfered with the staff's ability to carry out medical treatment.

CONCLUSIONS

The use of talismans in a technologically advanced western society is more frequent than may have been thought. Medical and paramedical personnel dealing with very ill patients should be aware of the emotional and psychological implications of such beliefs and practices on patients and their families.

[Laser treatment of airway obstruction in infants and children]

Airway obstruction during infancy and childhood requiring surgical ablation is rare, and surgical intervention poses a significant challenge. During recent decades, appropriate endoscopic instrumentation, together with advanced laser beam technology have provided new operative modalities for such patients. From 1993 to 1995 we treated 40 infants and children, 26 males and 14 females, 13 days to 11 years old (mean 3.3 years) with Nd-YAG or CO2 laser. Obstructing lesions included granulation tissue or polyps (16 cases), septa or webs (27), or benign tumors (4). 7 had more than a single lesion. All were treated endoscopically under general anesthesia without any operative or postoperative deaths. Surgical intervention removed the obstruction and related symptoms in 34. In 6, laser treatment failed, necessitating additional surgical procedures. 3 had circumferential subglottic web. Operative complications included bleeding during removal of a hemangioma in 1 and recrudescence in another. Postoperative complications were transient respiratory failure and pneumonia in 6, all of which resolved with appropriate treatment. This series proves that laser technology is feasible in the treatment of airway obstruction during infancy and childhood, and is safe and effective.

Acute iron intoxication: the efficacy of deferiprone and sodium biocarbonate in the prevention of iron absorption from the digestive tract

To determine whether enteral deferiprone given after a loading dose of liquid iron interferes with iron absorption from the digestive tract, prospective randomized animal study was initiated using Sprague-Dawley rats. The rats were given 20 mg elemental iron/kg as a ferrous sulfate solution + 1 mEq sodium bicarbonate/kg, and then dosed orally with 150 mg deferiprone/kg immediately or after 15 min. Serum iron levels were measured at 1, 3, 5 and 24 h; feces were collected for 24 h. The 20 mg elemental iron/kg caused a significant and rapid increase in serum iron levels to > 350 micrograms/dL within 20 min of oral dosing. Deferiprone, if given immediately after the iron, produced a significant decrease in serum iron levels and a 2-fold increase in iron excretion in feces. Effectiveness was delayed when the deferiprone was given 15 min after the iron dosing. Enteral deferiprone might be useful in preventing cases of acute iron intoxication.

The effect of diazepam in the recovery of rabbits from acute acetaminophen intoxication

We have recently shown that diazepam can reduce mortality of acute iron overdose in rats. The mechanism for that effect is not yet defined. Our objective in the present study was to assess whether diazepam can similarly reduce mortality of experimental acute acetaminophen intoxication. Survival of rabbits was compared among four groups receiving 3 g/kg (body weight) of acetaminophen (LD40) orally each, followed by: 1) nothing (group I), 2) one oral dose of 140 mg/kg N-acetylcystein (NAC) an hour later (group II), 3) intramuscular injection of 7 mg/kg diazepam (group III), 4) intramuscular injection of 7 mg/kg diazepam and one oral dose of 140 mg/kg NAC an hour later (group IV). 37.5% of rabbits in group I died after 16 hours, whereas none of the rabbits in group III died, (p = 0.04). No animal died during the 96-hour observation period in groups II and IV. Two and four hours post drug administration, acetaminophen plasma concentrations (APC) were significantly lower among rabbits in group III than in group I (p = 0.0007 and 0.01, respectively) and significantly lower among rabbits in group IV than in those in group II (p<0.0001 and p = 0.03, respectively). Acetaminophen plasma concentrations 2 hours after drug administration were also significantly lower among rabbits in group III than in those in group II (p = 0.0002). Seven and 24 hours after dosage, APC tended to be higher among rabbits in group III than in those in group I, but not significantly so. Administration of diazepam without NAC did not prevent liver and renal dysfunction. We conclude that early administration of diazepam in acute experimental acetaminophen overdose in rabbits reduced APC and mortality, probably by slowing intestinal motility, which resulted in delayed acetaminophen absorption from the gastrointestinal tract.

Vipera palaestinae snake envenomations: experience in children

In Israel, Vipera palaestinae (V. palaestinae) is the most common venomous snake, accounting for 100-300 reported cases of envenomation every year. However, V. palaestinae snakebites in children have not been extensively investigated. The demographic features, treatment and outcome of V. palaestinae envenomation in 37 children treated in two medical centers over a 9 year period were retrospectively reviewed. The victims age ranged from 2-18 years with a mean age of 8.9 years. Twenty-nine children were males and eight were females. Twenty-one patients resided in rural areas, and 16 children were living in urban areas. Twenty-three (63%) of the patients were bitten on the lower limb; Twelve (33%) on the upper limb, and two on the head or neck (4%). Using a grading scale of one to three from minimal to severe envenomation, 15 (40.5%), 15 (40.5%) and 7 (19%) patients had mild, moderate and severe envenomation, respectively. Major complications of envenomation that were manifested after arrival consisted of compartment syndrome (two patients) and respiratory dysfunction (two patients). Specific monovalent antiserum for the treatment of V. palaestinae bite was given to 16 children (43%) of whom, four patients were in the severe group, seven and five in the moderate and mild groups respectively. No patient suffered a significant infection, tissue loss, permanent disability or death. We conclude that early ICU admission along with close monitoring and antivenom therapy is important in reducing morbidity and mortality in children systemically envenomed by V. palaestinae.

Acute iron intoxication: significant differences between sexes

Iron, one of the common medications in use among children and adults, is the leading cause of pediatric unintentional ingestion fatalities and is not an uncommon poisoning among adults. Accidental ingestion is common because iron-containing compounds are readily available, brightly colored, often sugar coated, and frequently considered harmless vitamins. There are no data on differences between sexes with regard to iron intoxication, and the management of iron overdose is the same for females and males. After oral administration by gavage of the LD50 of iron to Wistar rats, the pharmacokinetics of iron, baseline and peak serum iron levels, and mortality rates were compared between sexes. Prepubertal females died significantly more than males (p < 0.01), pubertal females died significantly earlier than males (p < 0.04), and the same was true among adult rats (p = 0.02). Baseline serum iron levels were not significantly different between prepubertal female and male rats, but female pubertal rats had significantly higher baseline iron levels than males (p = 0.006). After iron administration, females had significantly higher peak serum iron concentrations (p < 0.03). Mechanisms of iron absorption are still not completely known and, probably, there are differences in iron absorption between sexes, which may account for the differences in serum iron levels and mortality rates. While the therapeutic approach in cases of intoxication is individual, iron intoxication, as may be true for other poisonings also, treatments administered to females may need to be different from that given to males.

Heliox therapy for pneumothorax: new indication for an old remedy

STUDY OBJECTIVE

To evaluate a new method of treating pneumothorax: having the subject breathe a helium/oxygen mixture (heliox).

METHODS

We conducted a prospective, randomized, controlled study of nine white rabbits weighing 2.5 to 3.5 kg. Experimental pneumothorax was induced in all rabbits with the injection of 20 mL of air into the pleural space. The rabbits then breathed heliox, oxygen, or room air for 2 hours. Chest radiography was performed 5 minutes after induction of pneumothorax, then at 1 and 2 hours. We determined pneumothorax size on the chest radiograph by measuring the interpleural distance and expressing it as a percentage of the hemithorax.

RESULTS

At 2 hours the pneumothoraces in the heliox group had diminished from 17.50% +/- .50% to .17% +/- .29%; in the oxygen-breathing group they had diminished from 17.83% +/- 2.25% to .50% +/- .50%; and in the air-breathing group they had diminished from 18.50% +/- 3.12% to 17.33% +/- .25%. The difference between the air-breathing and the oxygen-breathing or heliox-breathing animals was highly significant; no significant difference was found between the oxygen and heliox groups (P<.0001).

CONCLUSION

Heliox, a safe and convenient therapy, is as effective as oxygen in reducing the volume of an experimental pneumothorax in rabbits.

Purpura fulminans induced by disseminated intravascular coagulation following infection in 2 unrelated children with double heterozygosity for factor V Leiden and protein S deficiency

Purpura fulminans is associated with homozygous protein C and homozygous protein S deficiency or may follow bacterial or viral infections. We present 2 children from 2 unrelated Arab families with purpura fulminans who were double heterozygotes for factor V Leiden inherited from their fathers and protein S deficiency inherited from their mothers. No previous thrombotic events have occurred in either patient or their respective family members. In one patient sepsis accompanied by disseminated intravascular coagulation appeared to be the trigger of purpura fulminans. In the other patient varicella infection preceded purpura fulminans and was also associated with disseminated intravascular coagulation. This report emphasizes the need for evaluation of hereditary defects in the inhibitory mechanisms of blood coagulation in patients with purpura fulminans at any age.

Incidence of recurrent intussusception following barium versus air enema

The aim of this study was to determine whether using air enema for acute intussusception is related to a higher rate of recurrence than other methods of treatment. A 10-y (1986-95) retrospective study was performed in a university-affiliated paediatric division. The overall recurrence rate for 97 patients with acute intussusception was 7.8% (10% of whom were treated non-surgically). There were no recurrences following the surgical treatment. In matched groups of patients, no risk factors were found for recurrence following air vs barium enema.

Hyperthermia-induced cardiac arrest in monkeys: limited efficacy of standard CPR

BACKGROUND

Successful resuscitation from heatstroke cardiopulmonary arrest has been only partially explored and the data covering the post resuscitation pathophysiology leading to secondary arrest is, in most cases, insufficient.

HYPOTHESIS

Following heatstroke-cardiopulmonary arrest, successful resuscitation may be achieved by standard CPR with surface cooling and administration of glucose. We ponder the sequence of early circulatory responses and the pathophysiological changes following successful resuscitation.

METHODS

We exposed 12 pigtail monkeys to total-body hyperthermia (cerebral T 42 degrees C) until cardiac arrest ensued. Standard external CPR with surface cooling and glucose 5% IV were administered for up to 30 min. Control group A (n = 6) was compared with experimental group B (n = 6), which received additional steroid, glucagon and hypertonic glucose during CPR attempts.

RESULTS

No significant differences were found between the outcome of the two groups. The 30-min CPR attempt succeeded in restoration of spontaneous circulation (ROSC) in 8/12 monkeys-5 animals from group A and 3 in group B. The animals in whom resuscitation was unsuccessful had significantly prolonged periods of rectal temperature exceeding 42.5 degrees C (p < 0.05), and significantly higher rectal temperatures at the end of 30 min of CPR and cooling (p < 0.05). All the resuscitated animals later rearrested at 158 +/- 68 (95-228) min after ROSC; pulmonary edema occurred in 6/8 animals.

CONCLUSIONS

We conclude that experimentally-induced heatstroke can be transiently reversed by standard resuscitative procedures, but is followed by a delayed, irreversible, secondary shock state, which could not be prevented by the treatment we employed. We were, however, able to document in detail the pathophysiologic processes involved in the resuscitation, and the irreversible shock one sees after "successful" CPR.

Intussusception: a 9-year survey (1986-1995)

BACKGROUND

Acute intussusception has different clinical features in various parts of the world. The goal of this study was to determine the clinical presentation in different ethnic groups in Israel.

METHODS

A retrospective chart review of a 9-year period (1985-1995) was carried out at a university medical center. Data extracted included age, sex, ethnic origin, presenting symptoms and signs, the type of enema (barium or air), and the success rate of non-surgical reduction of the intussusception.

RESULTS

Ninety patients suffering from intestinal obstruction due to acute intussusception were admitted. The triad of intermittent screaming attacks, lethargy, and vomiting was observed in 37.5% of study subjects. The majority of patients were admitted during the warmer months of the year. The average age of the patients was 7.8 +/- 3.7 months; 70% of them were between the ages of 4 and 9 months and 92.5% under 1 year of age. The female-to-male ratio was 1:2.1. Air enema was superior to the barium enema in achieving reduction (p < 0.01). The incidence in the Jewish population was similar to that observed in other surveys, and twice that found in the Arab population in our region (p < 0.05).

CONCLUSIONS

The overall clinical presentation of acute intussusception found in our study does not differ from other studies. The lower incidence of acute intussusception found in the Arab population can be explained by ethnic, genetic, or nutritional factors.

Visual evoked potentials: a diagnostic test for migraine headache in children

Visual evoked potentials (VEPs) were performed in a blind fashion in 114 children aged 3 to 17 years with different types of headaches, in order to investigate whether this could be helpful in the diagnosis of migraine versus other types of headaches in children. The study showed that the amplitude between P100 and N2 was significantly larger in children with migraine headaches (mean 19.8 microvol, SD 7.75) compared with other types of headaches (mean 13.1 microvol, SD 7.45). These results suggest that the sensitivity of VEP P100 amplitude to distinguish migraine headaches in children is 67%, the specificity of VEP is 83%, and the predictive positive value is 83%. VEP study might be helpful in work-up of a child with headache, particularly a young child, when signs and symptoms may not be characteristic.

Postural stability by computerized posturography in minor head trauma

Mild head injuries are very common among young children. Often, these injuries are followed by a variety of subjective complaints termed posttraumatic syndrome. Posturography (balance test) was performed immediately after the trauma in 21 children who had sustained mild head injury. Significant difference in performance was observed in head-injured children in all subparts of the test as compared with a control group. We conclude that posturography may serve as a simple cost-effective method in qualifying the posttraumatic imbalance.

Severe pseudohypoaldosteronism in a pair of twins not associated with hydramnios

A pair of non-identical twins with severe pseudohypoaldosteronism (PHA) were followed over a period of 4 years. The diagnosis was based on dehydration, hyponatremia, hyperkalemia, high urine sodium/potassium ratios, and high serum concentrations of aldosterone and renin. Sweat and saliva electrolyte concentrations were high, suggesting multifocal target-organ unresponsiveness to mineralocorticoids. No hydramnios was observed during pregnancy. Despite continuous treatment with sodium chloride and sodium bicarbonate (< or = 20 g/day) and cation exchange resin (Kayexalate, sodium polystyrene sulfonate, < or = 4 g/kg per day), the children had repeated episodes of dehydration, hyponatremia, and hyperkalemia. Growth velocity was normal in both twins. Catch-up growth was observed following infancy in the first twin. Normalization of plasma aldosterone, electrolytes, and renin concentrations was achieved at the age of 9 months.

Peritoneal ventilation in rabbits: augmentation of gas exchange with cisapride

BACKGROUND

Peritoneal ventilation has been shown to be effective in achieving extrapulmonary oxygenation and carbon dioxide elimination in an animal model of severe adult respiratory distress syndrome (ARDS). Cisapride is a "prokinetic" agent (increases gastric emptying), that may increase the splanchnic circulation and thus favourably affect gas exchange in peritoneal ventilation.

METHODS

Using Doppler ultrasound the effect of cisapride on the portal venous circulation was examined in eight spontaneously breathing rabbits and the effect of cisapride on gas exchange in five rabbits spontaneously breathing room air was compared with that of a control group who did not receive cisapride. Its effect on gas exchange in five rabbits with ARDS being treated with mechanical lung and peritoneal ventilation was compared with that of a control group, and its effect on gas exchange in five rabbits with ARDS treated with conventional ventilation was also compared with that of a control group.

RESULTS

Enteral administration of cisapride increased portal venous blood velocity, as measured ultrasonographically, by a mean of 188% one hour after receiving the drug. In rabbits with ARDS being treated with both peritoneal ventilation and mechanical ventilation to the lungs, those receiving cisapride had arterial oxygen tensions 1.5-3 times that of controls. Cisapride had no effect on arterial blood gas tensions in rabbits who were spontaneously breathing room air, nor in rabbits with ARDS who received only conventional mechanical lung ventilation.

CONCLUSIONS

Cisapride increases arterial oxygenation in rabbits with severe ARDS treated with peritoneal ventilation, probably due to its ability to increase splanchnic circulation. It should be considered as an adjuvant medication to peritoneal ventilation.

Airway obstruction in neonates and children: surgical treatment

OBJECTIVE

This review of 54 infants and children with airway obstruction who were treated surgically emphasizes the importance of the surgical indications with respect to various anomalies causing airway obstruction and the surgical approach to their management.

PATIENTS

There were 4 etiologic groups of airway obstruction. Group A comprised 12 infants with subglottic stenosis; Group B--20 infants with tracheomalacia; 21 patients (Group C) with anatomic narrowing of the trachea; and 1 infant (Group D) with laceration of a main bronchus.

METHODS

The surgical procedures performed included anterior laryngotracheal decompression in 12 infants, aortopexy in 19; 1 pulmonary arteriopexy; tracheal stenting with an autologous rib graft in 3 and with Marlex mesh in 1. Tracheal widening, using a free tibia autologous graft, was performed in 3 patients; transbronchoscopic excision in 12; anterior tracheal wedge resection in 4, and segmental tracheal resection and anastomosis in 1 patient. The lacerated bronchus was repaired with fine Dexon sutures.

RESULTS

There were no operative deaths. With respect to the original indications for surgery, there were 3 failures--2 in Group A and 1 in Group C. Two patients died from causes unrelated to the procedures--one 10 days postoperatively, and the other 3 months after surgery.

CONCLUSIONS

The surgical approach to tracheal obstruction in infants and children offers effective treatment, with no operative mortality, a low complication rate, and good long term survival.

Acute scrotal pain complicating familial Mediterranean fever in children

Twenty-nine children with familial Mediterranean fever presented with 39 attacks of acute scrotal pain. Of these, 25 patients had an acute scrotum complicating familial Mediterranean fever and only four had testicular torsion. Scrotal pain was the only manifestation of a familial Mediterranean fever crisis in 36 episodes and in 15 boys scrotal involvement was the first manifestation of the condition. Fourteen patients were treated medically. Of 15 patients who underwent scrotal exploration there were no definite diagnostic findings in 11 and four had testicular torsion. Three cardinal features strongly suggest the diagnosis of acute scrotum in familial Mediterranean fever in a boy of Mediterranean origin with a relevant family history: recurrent scrotal pain or swelling; body temperature above 37.5 degrees C; and gradual onset of pain, usually of more than 12 h duration. Conservative management can safely be undertaken in these boys without fear of losing a salvageable testis.

Peritoneal ventilation: an animal model of extrapulmonary ventilation in experimental adult respiratory distress syndrome

Adult respiratory distress syndrome (ARDS) is a critical medical problem in which severe arterial hypoxemia is often poorly responsive to conventional modes of mechanical ventilation. We studied the efficiency of mechanical ventilation of the peritoneal cavity in rabbits with experimental ARDS caused by lung lavage. The study shows that peritoneal ventilation is significantly effective in oxygenation of hypoxemic animals with ARDS and is also effective for carbon dioxide elimination. Peritoneal ventilation may be considered as an investigational method for extrapulmonary oxygenation in severe intractable hypoxemia caused by ARDS.

Holocarboxylase synthetase deficiency: a treatable metabolic disorder masquerading as cerebral palsy

A 20-month-old boy of Jewish-Turkish origin presented with severe metabolic acidosis. He was born prematurely and had bacteremia during the neonatal period. Scaly skin eruption, developmental delay, generalized muscular hypertonia, and mild ventriculomegaly were noted during the 1st year. Holocarboxylase synthetase deficiency was diagnosed, and biotin and carnitine were administered. The skin rash and the organic aciduria resolved within several days, and at 30 months, his psychomotor development was appropriate for age. Metabolic evaluation should be performed in patients with combined neurologic and dermatologic symptoms even when medical history suggests a nonmetabolic etiology.

The management of epidural haematomas--surgical versus conservative treatment

We treated 14 children and infants during 1990-1993 who suffered severe head trauma with consequent epidural haematomas. We tried, in accordance with several recent publications, to follow part of them conservatively. The report describes the clinical and radiological features of these patients and discusses the criteria for conservative management of epidural haematoma in paediatric patients. The relevant literature is reviewed.

Phenothiazine treatment and respiratory distress syndrome in a child

An 11-year-old boy who was treated with a relatively high dose of methotrimeprazine meleate (Levemepromazine) a phenothiazine antipsychotic drug, was admitted to the pediatric intensive care unit suffering from respiratory distress syndrome. He required intensive treatment and support for 13 days. The persistent effects of methotrimeprazine meleate on various organs are typical of the prolonged biological action of the phenothiazine metabolites. The association of phenothiazine overdose and respiratory distress syndrome merits consideration.