Primary mediastinal malignancies in children: report of 22 patients and comparison to 197 adults

PURPOSE

Examine a contemporary series of patients with primary pediatric malignant mediastinal tumors and determine epidemiology, histology, treatment, and survival. Patients and Methods. All malignancies diagnosed between January 1, 1973 and December 31, 1995 were analyzed.

RESULTS

Twenty-two patients, age 18 years or less, with pediatric primary mediastinal malignancies were identified from a database of 110,284 patients with primary malignancies. During the same period, 197 adult patients with primary mediastinal malignancies were identified. Fifty-nine percent of the pediatric patients were male. Median age was 11 years. Lymphoma was present in 55%, neurogenic malignancies in 23%, malignant germ cell tumors in 18%, and sarcoma in 5%. Neurogenic tumors presented in infants and lymphomas and germ cell tumors presented in teens (p = 0.005). In treated children, surgery was used more often in neurogenic tumors and germ cell tumors than in lymphomas (p = 0.002). Five-year survival was 74% for lymphomas, 67% for neurogenic tumors, 25% for germ cell tumors, and 61% overall (p = 0.23). Compared to adults, children had more neurogenic tumors (p < 0.001) and fewer thymomas (p = 0.0499). There were no significant differences in staging or survival between children and adults.

CONCLUSIONS

Pediatric mediastinal malignancies occurred with a frequency of 1/5,013 patients with malignant tumors. Lymphoma, neurogenic tumors, and germ cell tumors predominated. Compared to adults, children had more neurogenic tumors and fewer thymomas. Within the pediatric group, differences were found in age of presentation between histologic groups. These differences between adults and children, and between infants and teens, should be considered when evaluating a patient suspected of having mediastinal malignancy.

Esophageal rupture after regional anesthesia: report of two cases

Esophageal perforation after anesthesia is rare. It is usually secondary to esophageal instrumentation. Only one case of barogenic rupture after regional anesthesia has been reported. We report two additional cases and present possible mechanisms for this unusual entity. Neither patient had anatomic abnormalities by history or preoperative endoscopy. However, both patients and the previously reported patient had esophageal dysmotility resulting from advanced age, alcoholism, intraoperative medications, and preexisting disease. Each patient experienced at least one episode of emesis with subsequent perforation of the distal one third of the esophagus. The previously reported patient died; both of our patients underwent successful surgical repair and are alive 2 years later. Intraoperative or postoperative emesis in patients with esophageal dysmotility appears to be the principal factor causing esophageal rupture after regional anesthesia. Prevention of nausea and vomiting and recognition of this high-risk population may minimize this complication in the future.

Primary mediastinal malignancies: findings in 219 patients

The purpose of this study was to determine the demographics, histology, methods of treatment, and survival in primary mediastinal malignancies. We did a retrospective review of the statewide New Mexico Tumor Registry for all malignant tumors treated between January 1, 1973 and December 31, 1995. Benign tumors and cysts of the mediastinum were excluded. Two hundred nineteen patients were identified from a total of 110,284 patients with primary malignancies: 55% of tumors were lymphomas, 16% malignant germ cell tumors, 14% malignant thymomas, 5% sarcomas, 3% malignant neurogenic tumors, and 7% other tumors. There were significant differences in gender between histologies (P < 0.001). Ninety-four percent of germ cell tumors occurred in males, 66% of neurogenic tumors were in females; other tumors occurred in males in 58% of cases. There were also significant differences in ages by histology (P < 0.001). Neurogenic tumors were most common in the first decade, lymphomas and germ cell tumors in the second to fourth decades, and lymphomas and thymomas in patients in their fifth decades and beyond. Stage at presentation (P = 0.001) and treatment (P < 0.001) also differed significantly between histologic groups. Five-year survival was 54% for lymphomas, 51% for malignant germ cell tumors, 49% for malignant thymomas, 33% for sarcomas, 56% for neurogenic tumors, and 51% overall. These survival rates were not statistically different (P > 0.50). Lymphomas, malignant germ cell tumors, and thymomas were the most frequently encountered malignant primary mediastinal neoplasms in this contemporary series of patients. Demographics, stage at presentation, and treatment modality varied significantly by histology. Despite these differences, overall five-year survival was not statistically different.

Successful treatment of adults with severe Hantavirus pulmonary syndrome with extracorporeal membrane oxygenation

OBJECTIVE

To describe our experience with the use of extracorporeal membrane oxygenation (ECMO) as a rescue therapy in adult patients with severe cardiopulmonary failure from Hantavirus pulmonary syndrome.

DESIGN

Case series.

SETTING

Tertiary referral center.

PATIENTS

Patients with confirmed Hantavirus infection, who developed severe cardiopulmonary failure in which conventional therapy was assessed as being unsuccessful.

INTERVENTIONS

Records of previous patients treated for Hantavirus pulmonary syndrome were reviewed and findings consistent with 100% mortality were found.

MEASUREMENTS AND MAIN RESULTS

Findings associated with a 100% mortality rate were a) cardiac index of <2.5 L/min/m2; b) serum lactate concentration of >4.0 mmol/L (normal range 0.0 to 2.2); c) pulseless electrical activity or ventricular fibrillation or ventricular tachycardia; and d) refractory shock despite fluid resuscitation, and vasoactive medications. From 1994 to 1996, seven patients were admitted with confirmed Hantavirus pulmonary syndrome and severe cardiopulmonary failure. Three of the seven patients had at least two of the four criteria for a 100% mortality rate listed above, and appeared to be failing optimal conventional therapy. These three patients received support with venoarterial ECMO. The first patient was placed on ECMO during cardiac arrest and died. The next two patients who received ECMO for Hantavirus pulmonary syndrome survived after relatively short, uncomplicated ECMO runs, and were discharged without complications.

CONCLUSIONS

ECMO successfully provided cardiopulmonary support in two patients with severe Hantavirus pulmonary syndrome who survived with a good outcome. Our experience suggests that ECMO is a beneficial therapy for patients critically ill with Hantavirus pulmonary syndrome.

Role of poloxamer 188 during recovery from ischemic spinal cord injury: a preliminary study

Paraplegia following aortic surgery is not a common event. When it does occur it significantly alters the patient's outcome. Poloxamer 188 (P188) has been shown in the experimental animal to increase regional blood flow to ischemic areas. In order to investigate its protective effect during aortic cross-clamping, 23 animals were randomized to two groups (placebo n = 11, P188n = 12) and received an intravenous injection of placebo or P188 (200 mg/kg), and underwent occlusion of the thoracic aorta and both subclavian arteries for a period of 13 minutes. They were then connected to an intravenous pump delivering either placebo or P188 (250 mg/kg/hr at a rate of 0.942 ml/hour) for 48 hours. Hindlimb function was appraised, daily for 30 days, by a lesion score (0-15). Spinal cord injury was assessed by a histologic score (0-3) based on the degree of gray and white matter gliosis, number of motor neurons, and white matter myelination. Analysis of variance for repeated measures did not reveal significant difference between P188 and placebo groups (P = 0.66). Similarly, the mean histologic scores (placebo = 1.54 +/- 0.41 SE, P188 = 1.08 +/- 0.33 SE) did not differ (Wilcoxon, P = 0.43). We conclude that intravenous administration of P188 before, during, and for 48 hours after aortic cross-clamping does not prevent paraplegia or improve the long term neurologic outcome.

Gangliosides and spinal cord ischemia secondary to aortic cross-clamping in the rat model

Gangliosides, complex glycolipids of the nervous system cell membranes, have been found effective both in reducing the degree of ischemic injury and in stimulating neuronal regeneration during the recovery period. In order to investigate their neuroprotective effect during spinal cord ischemia, 60 male Sprague-Dawley rats underwent occlusion of the thoracic aorta and both subclavian arteries for 13 min. In the postoperative period, function of hindlimbs was appraised, daily for 30 days, by a deficit score (0-15). The animals were then killed and spinal cord injury was assessed by a histologic score (0-3) based on the degree of gray and white matter gliosis, number of motor neurons, and white matter myelination. The rats received intraperitoneal injection of placebo (n = 29) or GM-1 30 mg/kg (n = 31) daily, from 2 days prior to surgery to 15 days after. The scores of each group for each day were analyzed by repeated measures analysis of variance. The rate of recovery was better for GM-1 (P < 0.001) from the 15th to the 30th day. A trend was seen toward lower scores in the GM-1 group (P = 0.056). Mean histologic scores (placebo = 1.14 +/- 0.23 SE, GM-1 = 1.58 +/- 0.22 SE) did not differ (Wilcoxon, P = 0.17). The present data support the hypothesis that functional improvement after spinal cord ischemia due to aortic occlusion is enhanced by the administration of gangliosides. Optical microscopy could document only irreversible injury and might not be sensitive enough to detect subtle changes during recovery of neural elements.

NMDA receptor blockade and spinal cord ischemia due to aortic crossclamping in the rat model

Recent brain research proposes that, during ischemia, synaptically released excitatory amino acid neurotransmitters accumulate at toxic concentrations with ensuing neuronal death. Their action is mediated by the receptor subtype N-methyl-D-aspartate (NMDA). The protective effect of NMDA receptor blockade with intrathecal MgSO4 and MK-801 was investigated during spinal cord ischemia induced by aortic occlusion of 12 minutes. Male Sprague-Dawley rats, 250-300g, underwent intrathecal administration of 20 microL of normal saline (SA n = 16), MgSO4 1M (MG n = 16), or MK-801, 25 mM solutions (MK n = 16) in a randomized order. After 2 hours, the animals underwent occlusion of the thoracic aorta and subclavian arteries for 12 min. An additional control group (CO n = 16) underwent occlusion for 12 minutes, without intrathecal injection. The animals were scored according to their functional performance (LS = lesion score) each day for four days by a blinded observer. Mean LS were calculated for each group at a given day. Treatment and control groups were not different at day 1 (P = 0.302). Group MG was improved from groups SA (P = < 0.0039) and CO (P = < 0.0048) at day 4. This study demonstrates that although intrathecal NMDA receptor blockade with MgSO4 or MK-801 does not prevent paraplegia due to spinal cord ischemia in the rat, it could however influence the rate of recovery after ischemic injury.

Cardiac stab wound resulting in a left anterior descending artery to left ventricular fistula with delayed pericardial tamponade

We describe the third known case of a traumatic left anterior descending artery to left ventricular fistula. Emergency operative repair was required on day 7 for delayed pericardial tamponade. The significant incidence of late serious sequelae with traumatic coronary artery fistulas suggests that early surgery is warranted.

Constrictive pericarditis from Nocardia asteroides infection

Human nocardiosis usually involves the respiratory tract or the skin but may disseminate to virtually any organ. It occurs in immunocompromised hosts as well as individuals with no apparent predisposition. Involvement of the pericardium is uncommon, having been reported infrequently in the past, but mandates surgical management. This report describes the course of a patient with chronic constrictive pericarditis from nocardia successfully treated with pericardiectomy and appropriate antibiotic therapy.

Peritoneopericardial diaphragmatic hernia discovered at coronary bypass operation

A 68-year-old man was discovered to have a large peritoneopericardial hernia when operated on for coronary artery bypass. Such hernias are very unusual. The pathogenesis, clinical presentation, and management of this problem are discussed.

Great vein and right atrial thrombosis in critically ill infants and children with central venous lines

We performed a retrospective review of echocardiographic data files of infants and children hospitalized in the Newborn and Pediatric Intensive Care Units. Echocardiograms were examined to detect the presence and evolution of great vein and right atrial thrombosis in patients with central venous lines. Thirty-seven patients were identified over a five-year period. Echocardiograms were performed, not routinely, but in response to specific indications including catheter malfunction, thrombocytopenia, persistent chylothorax, bacterial or fungal sepsis, and superior vena cava syndrome. Fifteen of 37 patients died, 13 of them during the hospitalization in which the thrombus was discovered. Thrombolytic agents and surgery were used to treat selected patients, with mixed results. Two of the 22 survivors have significant disability related to the thrombus or complications arising from it. We conclude that great vein and/or right atrial thrombosis is a common complication of central venous catheterization in small infants and children; moreover, the morbidity and mortality relating to this complication is substantial.

Rate-adaptive cardiac pacing in children using a minute ventilation biosensor

Chronotropic integrity is required for a normal cardiac output response to exercise. We evaluated a rate-adaptive ventricular demand pacemaker (Telectronics, META-MV) which uses minute ventilation as the sensed physiological variable for adjusting pacing rate, in seven young patients with a mean age of 11.4 years. All patients had clinically significant bradycardia related to complete heart block (n = 4) or sinus node dysfunction (n = 3). For the entire group, paced heart rates increased from 70 +/- 10 beats/min to 151 +/- 19 beats/min with exercise testing. The onset of rate adaptation took less than 30 seconds. Changes in paced rate were linearly related to workload, VO2 (5.9 to 20.7 mL/min/kg) and minute ventilation (8-65 L/min). The decline in pacing rate after exercise was related directly to the gradual decrease in minute ventilation and VO2. Our data show that minute ventilation closely and accurately reflects the metabolic demands of varying workloads in children and can be used to achieve physiological, rate-adaptive pacing.

Communicating hydrocephalus: a reversible complication of the Mustard operation with serial hemodynamics and long-term follow-up

Severe superior vena caval (SVC) obstruction following the Mustard operation resulted in substantially increased intracranial pressure in 3 patients. A pathophysiological mechanism is postulated to explain the cerebral edema in 1 and the communicating hydrocephalus in 2. Following surgical relief of the obstruction in the latter 2, there was a decrease in both the rate of head growth and the ventricular size. It is of note that despite the angiographic appearance of azygous decompression, the pressure elevation from the SVC obstruction was transmitted to the brain. The long-term follow-up at three and four years of the 2 infants with communicating hydrocephalus suggests that aggressive treatment is compatible with a favorable outcome.