Shock after blast wave injury is caused by a vagally mediated reflex.

OBJECTIVE: Bomb blast survivors occasionally suffer from profound shock and hypoxemia without signs of external injury. We hypothesize that a vagally mediated reflex such as the pulmonary defensive reflex is the cause of shock from blast wave injury. This study was a prospectively randomized, controlled animal study. METHODS: By using a previously described model of blast wave injury, we randomized rats to one of four groups: control, blast-only, bilateral cervical vagotomy plus atropine 200 microg/kg i.p. only, and bilateral cervical vagotomy plus atropine 200 microg/kg i.p. before blast injury. Cardiopulmonary parameters were recorded for 90 minutes after the blast or until death. RESULTS: Bradycardia, hypotension, and absence of compensatory peripheral vasoconstriction, typically seen in animals subjected to a blast pressure injury, were prevented by bilateral cervical vagotomy and intraperitoneal injection of atropine methyl-bromide. Hypoxia and lung injury were not statistically significant between the blasted groups, suggesting equivalent injury. CONCLUSION: Our data implicate a vagally mediated reflex such as the pulmonary defensive reflex as the cause of shock seen immediately after a blast pressure wave injury.

Treating the snakebitten child in North America: a study of pit viper bites.

BACKGROUND/PURPOSE: Snakebite envenomation is a potentially life-threatening form of trauma, the dangers of which are amplified in children because their smaller size increases the relative dose of venom received. The authors reviewed a large series of snakebitten children to address the medical and fiscal issues of treating these patients. METHODS: The records of 37 snakebitten children (1987 through 1997) were analyzed for demographic data, signs of envenomation, use of specific therapies (antivenin, blood products, or surgery), length of hospitalization, complications, and cost of care. RESULTS: Fifty-four percent of the children had a major envenomation demonstrated by systemic symptomatology, laboratory analysis, or need for surgery. All children made full recoveries with most receiving only supportive care (92%). The average time to emergency department presentation was 8 hours, where all children with major envenomations and those requiring specific therapies (surgery, clotting factors) were identified. Cost analysis showed an average of $2,450 dollars per child with the majority of expenses attributable to length of hospitalization. CONCLUSIONS: Most snakebitten children completely recover with minimal supportive care, and they can be cared for safely and cost effectively as outpatients if no signs of major envenomation are noted within 8 hours of the bite.

Extracorporeal life support for nonimmune hydrops fetalis.

BACKGROUND/PURPOSE: Most babies born with idiopathic nonimmune hydrops fetalis (NIHF) suffer generalized cardiopulmonary collapse and die despite maximal medical therapy. With reported survival rates of less than 10%, many centers consider NIHF an unsalvageable situation and the babies who have this condition, untreatable. In this study, the authors questioned if the aggressive use of extracorporeal life support (ECLS) could salvage this condition and improve the chances of survival for babies born with NIHF. METHODS: The Extracorporeal Life Support Organization's (ELSO) neonatal registry was searched for all available information on babies treated for hydrops fetalis. The ELSO records of all hydropic babies were then reviewed to exclude those babies who had identifiable causes of hydrops. Survival statistics were then calculated for the remaining core group of idiopathic NIHF babies before separating them into two groups based on survival. A detailed analysis comparing the survivors with nonsurvivors was then performed. RESULTS: A total of 28 hydropic babies were identified in the ELSO registry. Four babies were excluded from analysis because of identifiable causes of hydrops (two with congenital diaphragmatic hernia, one with Rh incompatibility, and one with fetal anemia). Of the remaining 24 babies who had NIHF, 54% (13 babies) survived the neonatal period and were discharged from the hospital. Analysis comparing the survivors with the nonsurvivors in our study showed that the groups were similar in their gestational ages, birth weights, Apgar scores and the time to initial intubation. The most distinguishing factor of survival in our study was that the survivors, on average, received ECLS support 3 days sooner than nonsurvivors (mean, 17.5 +/- 1.3 hours of life for survivors v 105 +/- 36.6 hours for nonsurvivors, P < or = .05). CONCLUSION: Idiopathic NIHF should no longer be considered an untreatable condition but a new indication for ECLS that, when begun early, may significantly improve the chances of survival for these babies previously considered "unsalvageable."

The spectrum of pediatric injuries after a bomb blast.

The spectrum of pediatric injuries seen after a bomb blast is poorly documented. The pathophysiology of blast injuries differ significantly from other forms of trauma and typically result in large numbers of distinctly patterned injuries. On April 19, 1995, a truck bomb was detonated directly adjacent to the Alfred P. Murrah Federal Building in Oklahoma City, Oklahoma. A total of 816 adults and children were injured or killed as a direct result of the blast. Twenty infants and children were seated by the window of the second floor day care center at the time of the explosion. The injuries incurred by all children involved in the blast were studied. Nineteen children, 16 of whom were in the day care center, died as a direct result of the blast. The injury patterns among the 19 dead children included a 90% (17 of 19) incidence of skull fractures, 15 of those with cerebral evisceration (skull capping); 37% with abdominal or thoracic injuries; 31% amputations; 47% arm fractures, 26% leg fractures; 21% burns; and 100% with extensive cutaneous contusions, avulsions, and lacerations. Forty-seven children sustained nonfatal injuries with only seven children requiring hospitalization. The injuries sustained by the seven hospitalized children included two open, depressed skull fractures, with partially extruded brain, two closed head injuries, three arm fractures, one leg fracture, one arterial injury, one splenic injury, five tympanic membrane perforations, three corneal abrasions, and four burn cases (1 > 40% body surface area [BSA]). After a bomb blast, pediatric patients sustain a high incidence of cranial injuries. Fractures and traumatic amputations are common. Intraabdominal and thoracic injuries occur frequently in the deceased but infrequently in survivors.

Abdominal wall defects in infants. Survival and implications for adult life.

OBJECTIVE: The authors study reviewed patients who underwent operations for omphalocele and gastroschisis to determine survival, morbidity, and long-term quality of life. METHOD: Clinical follow-up of 94 patients cared for with omphalocele and gastroschisis during a 10- to 20-year period after birth. RESULT: Eighty-three patients survived initial treatment. Sixty-one had long-term follow-up. Mean follow-up in the group was 14.2 years. Survival was favorable in the absence of lethal or co-existing major congenital anomalies. Nineteen patients required 31 reoperations, most for abdominal wall hernias and the sequelae of intestinal atresia. Current quality of life was described as favorable (good) in 80% of patients. CONCLUSIONS: Survival rate in patients with abdominal wall defects is favorable and deaths occur substantially in patients with co-existing lethal, or multiple, congenital anomalies. Reoperative surgery is necessary principally in those patients who have postclosure abdominal wall hernias, and in those with bowel atresia at birth. Reoperations are not likely to be necessary after school age. Quality of life in survivors is patient-perceived as entirely satisfactory.

Transseptal decompression of the left heart during ECMO for severe myocarditis.

A 16-month-old boy suffered a cardiac arrest as a result of acute myocarditis, and venoarterial extracorporeal membrane oxygenation was instituted. Twelve hours later, acute left heart distention developed with cessation of left ventricular ejection. Under transesophageal echocardiographic guidance, a long introducer was placed into the left atrium through a transseptal puncture and connected in-line to the venous circuit. Within hours, left ventricular function improved and ejection returned. Left heart decompression was continued for 5 days, and the patient was weaned from extracorporeal membrane oxygenation after 6 days with normal cardiac and neurologic function.

An appropriate negative bronchoscopy rate in suspected foreign body aspiration.

Aspiration of foreign bodies in children can lead to illness and even death if not recognized and treated promptly. Seventy-six patients were referred to our hospital for suspected foreign body aspiration. The following is a retrospective review of their diagnosis and treatment. There was no foreign body found at bronchoscopy in seven patients (9 percent), and there were nine patients (12 percent) with bronchial foreign bodies who had a delay in diagnosis of foreign body aspiration. The delay averaged 35 days. These children, as a result of a prolonged period before diagnosis, were treated unnecessarily for pneumonia and asthma. Once correctly diagnosed, they had a significantly longer hospital stay. We propose that some negative bronchoscopies are necessary in order to prevent the morbidity that occurs from a missed foreign body aspiration.