Search PubMed⌕ Search

Biomedical subjects

N E Green

Publications and source records attributed to N E Green.

At least 19 recordsLinked to original sources
PubMed2000

Ketamine sedation for the reduction of children's fractures in the emergency department.

BACKGROUND: There recently has been a resurgence in the utilization of ketamine, a unique anesthetic, for emergency-department procedures requiring sedation. The purpose of the present study was to examine the safety and efficacy of ketamine for sedation in the treatment of children's fractures in the emergency department. METHODS: One hundred and fourteen children (average age, 5.3 years; range, twelve months to ten years and ten months) who underwent closed reduction of an isolated fracture or dislocation in the emergency department at a level-I trauma center were prospectively evaluated. Ketamine hydrochloride was administered intravenously (at a dose of two milligrams per kilogram of body weight) in ninety-nine of the patients and intramuscularly (at a dose of four milligrams per kilogram of body weight) in the other fifteen. A board-certified emergency physician skilled in airway management supervised administration of the anesthetic, and the patients were monitored by a registered nurse. Any pain during the reduction was rated by the orthopaedic surgeon treating the patient according to the Children's Hospital of Eastern Ontario Pain Scale (CHEOPS). RESULTS: The average time from intravenous administration of ketamine to manipulation of the fracture or dislocation was one minute and thirty-six seconds (range, twenty seconds to five minutes), and the average time from intramuscular administration to manipulation was four minutes and forty-two seconds (range, sixty seconds to fifteen minutes). The average score according to the Children's Hospital of Eastern Ontario Pain Scale was 6.4 points (range, 5 to 10 points), reflecting minimal or no pain during fracture reduction. Adequate fracture reduction was obtained in 111 of the children. Ninety-nine percent (sixty-eight) of the sixty-nine parents present during the reduction were pleased with the sedation and would allow it to be used again in a similar situation. Patency of the airway and independent respiration were maintained in all of the patients. Blood pressure and heart rate remained stable. Minor side effects included nausea (thirteen patients), emesis (eight of the thirteen patients with nausea), clumsiness (evident as ataxic movements in ten patients), and dysphoric reaction (one patient). No long-term sequelae were noted, and no patients had hallucinations or nightmares. CONCLUSIONS: Ketamine reliably, safely, and quickly provided adequate sedation to effectively facilitate the reduction of children's fractures in the emergency department at our institution. Ketamine should only be used in an environment such as the emergency department, where proper one-on-one monitoring is used and board-certified physicians skilled in airway management are directly involved in the care of the patient.

Analgesics↗
PubMed1999

Leukocyte entry into sites of inflammation requires overlapping interactions between the L-selectin and ICAM-1 pathways.

Leukocyte interactions with vascular endothelium during inflammation depend on cascades of adhesion molecule engagement, particularly during selectin-mediated leukocyte rolling. Leukocyte rolling is also facilitated by members of the integrin and Ig families. Specifically, leukocyte rolling velocities during inflammation are significantly increased in ICAM-1-deficient mice, with ICAM-1 expression required for optimal P- and L-selectin-mediated rolling. Elimination of ICAM-1 expression in L-selectin-deficient mice significantly reduces leukocyte rolling. Whether disrupted leukocyte rolling in L-selectin and ICAM-1 double-deficient (L-selectin/ICAM-1-/-) mice affects leukocyte entry into sites of inflammation in vivo was assessed in the current study by using experimental models of inflammation; thioglycollate-induced peritonitis, chemokine-induced neutrophil migration to the skin, delayed-type hypersensitivity responses, rejection of allogeneic skin grafts, and septic shock. In many cases, the loss of both L-selectin and ICAM-1 expression dramatically reduced leukocyte migration into sites of inflammation beyond what was observed with loss of either receptor alone. In fact, the effects from loss of both L-selectin and ICAM-1 effectively eliminated multiple chronic inflammatory responses in L-selectin/ICAM-1-/- mice. By contrast, the combined loss of L-selectin and ICAM-1 expression had minimal effects on the generation of Ag-specific T cell responses or humoral immunity. Thus, members of the selectin and Ig families function synergistically to mediate optimal leukocyte rolling and entry into tissues, which is essential for the generation of effective inflammatory responses in vivo.

Animals↗
PubMed1998

Bilateral peroneal nerve palsy secondary to a knee board: report of two cases.

We report on two patients who developed bilateral peroneal nerve palsy after using a knee board behind a water ski boat. This device causes the rider's knees to be in a hyperflexed position secured with a strap across the thighs. Treatment for this compressive neuropathy is conservative. Recreational users may wish to limit the duration and frequency of participation in this sport, thus decreasing the predisposition to prolonged nerve compression. In addition, manufacturers may consider making fundamental design changes such as padding the nylon straps or outrigger devices that contact the proximal lateral tibia.

Adolescent↗
PubMed1997

Video-assisted thoracoscopic diskectomy and fusion.

Thoracoscopic diskectomy has been described in adults as an alternative to thoracotomy for access to the anterior spine for correction of scoliosis, but its use in children for correction of spinal deformities has not been reported. Eight patients have undergone video-assisted thoracoscopic diskectomy with fusion before posterior instrumentation. In five patients, the posterior fusion and instrumentation followed the thoracoscopic procedure under the same anesthesia; in three patients it was staged and performed 1 week later. The mean time required for the thoracoscopic procedure was 174 minutes. Intraoperative bleeding requiring transfusion developed in one patient. No other complications occurred. The authors conclude that the minimally invasive approach for access to the thoracic cavity for anterior diskectomy and fusion will be the preferred approach because of the potential for significant reduction in postoperative discomfort and complications such as atelectasis and pneumonia. Postoperative hospitalization may not be decreased, however, because the patient must still recover from the open posterior instrumentation and fusion operation.

Adolescent↗
PubMed1997

Osteochondritis dissecans as a cause of developmental dislocation of the radial head.

Osteochondritis dissecans of the capitellum produces an area of focal necrosis that may result in a potentially unstable relationship between the capitellum and the radial head. Seven patients with developmental instability of the radial head secondary to osteochondritis dissecans of the capitellum treated between 1984 and 1995 were studied. All patients were male with an average age of 13 years. The most common symptom was pain with a decrease in range of motion. Patients lacked an average of 24.3 degrees extension. Initial plain radiographs were most helpful for evaluating the relationship of the radial head to the capitellum, and tomography or magnetic resonance imaging were helpful for the detection of loose bodies. The most common direction for instability was posterolateral. Treatment varied from conservative management with nonsteroidal antiinflammatory medication to open reduction and internal fixation of an osteochondral fragment. The average followup was 3.2 years. At latest followup, 11 patients were pain free; however, they lacked an average of 17 degrees extension. Only 2 patients progressed to complete dislocation of the radial head. Developmental instability of the radial head may occur secondary to osteochondritis dissecans of the capitellum. Plain radiographs are sufficient for initial detection and followup. Treatment is determined by the presence of loose bodies and the characteristics of the osteochondral defect. Initial symptoms will resolve; however, lack of extension may persist.

Adolescent↗
PubMed1997

Paravertebral inflammation mistaken for neoplasm or abscess by MRI.

Magnetic resonance imaging (MRI) is a useful procedure for the evaluation of spinal pathology in children. The high sensitivity of soft tissue changes may lead to misinterpretation of paravertebral swelling caused by inflammation. We present a report of three patients with paravertebral soft tissue swelling caused by disk space infection or intervertebral disk space calcification. The findings shown by MRI were initially interpreted as neoplasm or abscess, which led to surgical procedures either planned or done. Surgeons need to exercise extreme care when interpreting soft tissue changes shown by MRI.

Abscess↗
PubMed1997

Decline of bone and joint infections attributable to haemophilus influenzae type b.

Haemophilus influenzae has been a major cause of infectious diseases in children and has been attributed as a significant cause of septic arthritis and osteomyelitis in children. With the advent of widespread vaccination, the incidence of Haemophilus influenzae meningitis and other infections has been well documented. This is thought to be the first report that documents the effect of vaccination on bone and joint infections. One hundred sixty-five cases of acute hematogenous osteomyelitis or septic arthritis treated at the Department of Orthopaedics at Vanderbilt University in the years before and after the advent of the Haemophilus influenzae vaccine to assess whether vaccination affected the incidence of these diseases. The data indicate that the Haemophilus influenzae vaccine has reduced to near 0 the incidence of bone and joint infections because of Haemophilus influenzae. These findings suggest that coverage of Haemophilus influenzae as part of the empiric antibiotic coverage may be no longer needed in the management of acute hematogenous osteomyelitis and septic arthritis in children.

Acute Disease↗
PubMed1996

Humoral immune responses in L-selectin-deficient mice.

L-selectin regulates lymphocyte migration by mediating lymphocyte attachment to high endothelial venules of peripheral lymph nodes (PLN). L-selectin-deficient mice display a 70 to 90% reduction in the number of lymphocytes within PLNs and a 30 to 55% increase in spleen cellularity. The altered distribution of lymphocyte subpopulations in L-selectin-deficient mice resulted in significantly elevated serum IgM and IgG1 levels and augmented humoral immune responses to T cell-independent and T cell-dependent Ags following i.p. immunization. By contrast, s.c. immunization of L-selectin-deficient mice with a T cell-dependent Ag resulted in serum IgM responses that were 40% lower when compared with wild-type littermates on day 7, while primary IgG responses were essentially absent. Most serum Ig responses were normal by day 14 and secondary responses were higher in L-selectin-deficient mice. Although lymphocytes from L-selectin-deficient mice were unable to enter Ag-stimulated lymph nodes through high endothelial venules, the cellularity of draining lymph nodes increased significantly following immunization. Germinal centers developed rapidly following immunization, although PLNs of L-selectin-deficient mice contained few follicles. Germinal centers within PLNs and the spleen were also consistently much larger and more well defined in L-selectin-deficient mice when compared with wild-type littermates. These results confirm that lymphocyte migration plays an important role in the initiation of humoral responses and demonstrate complementary and overlapping roles for the spleen and other peripheral lymphoid tissues in the generation of immune responses.

Animals↗
PubMed1996

Lyphocyte migration in L-selectin-deficient mice. Altered subset migration and aging of the immune system.

Lymphocyte trafficking across high endothelial venules (HEV) of peripheral lymph nodes (PLN) is dependent upon lymphocyte expression of L-selectin. Mice that lack this adhesion molecule provide an opportunity to determine the long-term role of L-selectin-mediated migration in the maintenance of leukocyte subpopulations. HEV in L-selectin-deficient mice were phenotypically, morphologically, and functionally comparable with wild-type mice, although there was a 70 to 90% reduction in the number of lymphocytes within PLN. These lymphocytes most likely entered PLN through the afferent lymphatics, since they did not migrate into PLN of normal mice during short-term homing experiments. The impaired trafficking of lymphocytes across PLN-HEV resulted in the accumulation of memory (CD18highCD44high) lymphocytes within PLN, and also altered the distribution of lymphocyte subpopulations within other tissues. Specifically, a 30 to 55% increase in splenic cellularity occurred due to increases in both naive and memory lymphocytes. Circulating lymphocyte numbers or subpopulations were not altered in young L-selectin-deficient mice, but circulating monocyte numbers were increased nearly threefold. In contrast, older L-selectin-deficient mice had disproportionate increases of both naive and memory CD4+ T cells present within spleen and blood. These results and the finding that memory lymphocytes in wild-type mice expressed L-selectin demonstrate a requirement for L-selectin in the regulation of memory lymphocyte migration. Therefore, L-selectin-dependent pathways of lymphocyte migration are important for the normal migration of both naive and memory lymphocytes.

Animals↗
PubMed1995

Reduction of forearm fractures in children using axillary block anesthesia.

One hundred eleven patients (age range 15 months-16 years, mean 9.6 years) with displaced forearm fractures who had axillary blocks performed by orthopaedists in the emergency room were retrospectively reviewed. Thirty-seven fractures involved the distal radius, 56 involved both bones of the forearm, and 12 involved the physis of the distal forearm. Three Monteggia fractures, one radial neck fracture, one olecranon with an associated radial neck fracture, and one distal radius fracture with an associated elbow dislocation also were included. Of the 111 axillary blocks, 105 were rated as effective. Potential complications of axillary block anesthesia (systemic toxicity, hematoma, infection, and brachial neuralgia) were not observed in this group of patients. The cost of axillary block reduction in the emergency room was less than one third that of general anesthesia in the operating room. Axillary block anesthesia is reliable, safe, and cost effective, and this study supports its use by orthopaedists in displaced forearm fractures in children.

Adolescent↗
PubMed1993

Late-onset pseudarthrosis of the dysplastic tibia.

Eleven children in whom a tibial fracture occurred after minor trauma had pre-existing dysplastic changes evident radiographically. These changes included cortical tapering, sclerosis, and formation of a cyst in the region of the medullary canal. Ten of the eleven patients had had no more fractures an average of fifteen years after the most recent fracture. Six of the fractures healed following prolonged immobilization in a cast, but four of the six tibiae were abnormally bowed anteriorly, and it was thought that a stress fracture could occur in the future. Four of the patients had a clinically straight tibia and radiographic evidence of thick cortices following corrective osteotomy, intramedullary fixation with bone-grafting, and prolonged immobilization in a cast. At the most recent follow-up examination, the eleventh patient had a persistent pseudarthrosis despite several operative procedures. While there were too few patients in this series for us to draw definite conclusions, our findings suggest that late-onset pseudarthrosis of a dysplastic tibia has a better prognosis than does congenital pseudarthrosis.

Bone Diseases, Developmental↗
PubMed1993

Acute transphyseal hematogenous osteomyelitis caused by Haemophilus influenzae with 5-year follow-up.

Acute hematogenous osteomyelitis is a well-recognized entity in infants and children. Over 90% of cases are caused by coagulase-positive Staphylococcus aureus, with other organisms only rarely implicated. Transepiphyseal osteomyelitis, because of the presence of infection on either side of the physis, usually results in growth arrest. The authors report the case of a 4-month-old child who had a transphyseal acute hematogenous osteomyelitis caused by Haemophilus influenzae and document complete resolution of the infection at 5-year follow-up with no clinical or radiographic evidence of growth arrest.

Acute Disease↗
PubMed1992

Comparison of closed reduction and percutaneous pinning versus open reduction and percutaneous pinning in displaced supracondylar fractures of the humerus in children.

A retrospective review of 29 children with displaced supracondylar humerus fractures was performed. Fifteen patients treated with closed reduction and percutaneous pinning and 14 patients treated with open reduction and percutaneous pinning were evaluated at a minimum of 18 months (range 18-80 months). Results were graded according to the criteria of Flynn et al. (Flynn JC, Matthews JG, Benoit RL: Blind pinning of displaced supracondylar fractures of the humerus in children. J Bone Joint Surg [Am] 56:263-272, 1974) using both cosmetic and functional evaluations. Excellent or good results were obtained in 14 of the 15 fractures treated with closed reduction and percutaneous pinning and in 12 of the 14 fractures treated with open reduction and percutaneous pinning. The three fair cosmetic results were associated with inadequate reduction and residual medial angulation. Ten to 15 degrees of motion loss occurred in three older patients. One patient in each group had a minor pintract infection. There were no cases of iatrogenic nerve injury or myositis ossificans. The treatment goal in displaced supracondylar humerus fractures in children is anatomic reduction. If an anatomic reduction cannot be achieved with closed reduction, open reduction is indicated. This can be done without an increased risk of complications.

Bone Nails↗