[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.