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Biomedical subjects

F L Rimell

Publications and source records attributed to F L Rimell.

33 records · Page 2Linked to original sources
PubMed1997

Recovery from doxacurium infusion administered to produce immobility for more than four days in pediatric patients in the intensive care unit.

Doxacurium was administered by titrated infusion to 14 pediatric patients for 4.7-12.3 days after laryngotracheal reconstruction to produce minimum spontaneous movement and less than five posttetanic movements of the first toe after stimulation of the posterior tibial nerve. Recovery was documented by stimulation of the ulnar nerve with 2 Hz for 2 s (train-of-four [TOF]) at intervals of 1 min and measurement of the ratio of the fourth to the first response (TOF ratio) at the adductor pollicis. During spontaneous recovery, the TOF ratio was between 0.4 and 0.7 for 0.6-3.3 h, mean (SEM) 2.2 (0.31) h. The TOF ratio equaled 1 between 4.7 and 23.0 h, mean (SEM) 11.0 (2.1) h after termination of doxacurium infusion. In six of the patients, weakness and decreased coordination were noted for a few days to weeks postoperatively. There were no complications related to impairment of upper airway function or ventilation in those patients who had recovery of neuromuscular transmission to the extent of TOF ratio equal to 1 prior to extubation or in those patients in whom weakness or lack of coordination was noted after tracheal extubation.

Child↗
PubMed1997

Pediatric laser bronchoscopy.

Endoscopic laser surgery can be performed in the airway safely and effectively when a team approach is used. Our team of anesthesia and surgical personnel prefers to treat lesions involving the supraglottic, glottic, or immediately subglottic trachea with a CO2 laser through the laryngoscope, using Venturi ventilation and intravenous sedation and pharmacological paralysis. For distal airway lesions, as far as the mainstem bronchi, our preference is to use manual positive pressure ventilation through a rigid bronchoscope with a flexible KTP or argon fiberoptic laser. Oxygen concentrations should be kept below 50% if possible and one should avoid material that can ignite. For lesions distal to the mainstem bronchi, we prefer to use a flexible bronchoscope through a standard endotracheal tube.

Anesthesia↗
PubMed1997

Pediatric respiratory papillomatosis: prognostic role of viral typing and cofactors.

Children with recurrent respiratory papillomatosis vary greatly in their clinical disease course. Many have mild disease with eventual remission while others present with an early aggressive airway obstructive course. This study consisted of 24 pediatric patients whose specimens underwent polymerase chain reaction analysis for cytomegalovirus (CMV), herpes simplex virus (HSV), and human papillomavirus (HPV) type. Nineteen of 24 specimens contained enough DNA for this study. None of the specimens were found to contain DNA from HPV-16, -18, -31, -33; CMV; or HSV, which contrasts with our previous findings in adults. Ten patients were infected by HPV-11 and seven of these underwent tracheotomy because of an aggressive tumorigenic clinical course. Nine patients were infected by HPV-6 alone of whom only two required a tracheotomy (P = 0.05, Fisher's Exact Test). The early airway obstructive course associated with HPV-11, however, had no bearing on achieving eventual disease remission, with decannulation achieved in eight of nine children.

Adult↗
PubMed1997

Diagnosis and management of left main stem bronchus compression.

There are four major variants of congenital vascular tracheal compression: innominate artery, aberrant subclavian, aorta or aortic arch anomaly, and pulmonary artery sling. These forms of vascular compression typically involve the trachea and/or the right main stem bronchus. We present eight cases of congenital vascular compression involving the left main stem bronchus. These cases represent a poorly understood variant of vascular tracheal compression. This variant represents approximately 10% of our pediatric tracheobronchial compression or stenosis patients. The finding, both noted endoscopically and now illustrated by magnetic resonance imaging, is caused by compression of the left main stem bronchus between the descending aorta and a portion of the pulmonary artery. Frequently, the descending aorta is in an abnormal anterior position with relation to the thoracic spine. Recognition of this entity is important in our experience and has influenced clinical management. In four of eight children, it required a surgical procedure directed toward the relief of the left main stem compression.

Abnormalities, Multiple↗
PubMed1996

Pediatric fiberoptic laser rigid bronchoscopy.

Use of the fiberoptic laser for treatment of tracheobronchial lesions in the adult is well established. However, there is a paucity of experience with the fiberoptic laser in the pediatric airway. Tracheal obstruction caused by granulation tissue or stenosis, as is often seen in children, may be effectively treated with this approach. This article documents the successful use as well as the technologic advantage of the flexible fiberoptic laser systems, primarily the potassium titanyl phosphate (KTP) laser, combined with standard pediatric rigid bronchoscopic equipment in 73 procedures involving 52 children (43 children younger than five years. with an average age of 21 months). Visualization was excellent, assisted or spontaneous ventilation was well maintained, and complications were few.

Adolescent↗
PubMed1996

Laryngotracheal reconstruction using microplates in a porcine model with subglottic stenosis.

Current techniques of laryngotracheal reconstruction require a choice between prolonged stenting (conventional technique) or short-term stenting with maintenance of sedation and paralysis until the airway has stabilized (single-stage laryngotracheal reconstruction). An alternative method is proposed using microplates to provide immediate airway stabilization without stenting. This study was designed to evaluate the long-term effects of microplate repair of stenosis of the subglottis and trachea on the growing larynx. Subglottic stenosis was produced in piglets using a transoral endoscopic technique. Eight animals underwent repair of the stenosis using an anterior cricoid split with microplate distraction and stabilization of the cricoid cartilage and first tracheal ring. The distraction was maintained and airway growth continued for the duration of this study. However, with growth of the larynx the plates migrated away from their original position. In 50% of the animals followed up for 90 days the plates migrated into the airway lumen. This study suggests that rigid distraction of the stenotic airway with microplates is a viable alternative to more traditional methods of repair. However, plate removal at some interval after surgery is required in the growing larynx in order to prevent migration of the plate into the airway.

Animals↗
PubMed1996

Tracheotomy in children with juvenile-onset recurrent respiratory papillomatosis: the Children's Hospital of Pittsburgh experience.

Despite the risk of airway obstruction, tracheotomy has been viewed with trepidation in the management of recurrent respiratory papillomatosis (RRP). The literature suggests that the injury associated with the tracheotomy site may initiate the progression of disease to the distal airway. Alternatively, patients who require tracheotomy for RRP may be predisposed to distal spread because of more aggressive disease. In an effort to clarify this issue, we reviewed the Children's Hospital of Pittsburgh experience with 35 patients with RRP between 1984 and 1994; 13 patients received tracheotomies. Tracheotomy patients presented at a younger age with more widespread disease, often involving the distal airway prior to tracheotomy. Although distal spread occurred in 50% of patients, it was generally limited to the tracheotomy site. Overall, outcome in the tracheotomy group was satisfactory. Complications related to the tracheotomy were rare. We conclude that tracheotomy is an appropriate option for significantly airway compromise in patients with RRP.

Child↗
PubMed1995

Characteristics of objects that cause choking in children.

OBJECTIVE: To characterize the types, shapes, and sizes of objects causing choking or asphyxiation in children and to compare these characteristics to current standards. DESIGN: To evaluate morbidity, retrospective 5-year medical record survey; to evaluate mortality, data reanalysis. SETTINGS: Pediatric hospital and consumer product testing laboratory. PATIENTS: All children (n = 449) who underwent endoscopy for foreign body aspiration or ingestion at Children's Hospital of Pittsburgh (Pa) between 1989 and 1993 and children (n = 449) whose deaths due to choking on man-made objects were recorded by the Consumer Product Safety Commission (CPSC) between 1972 and 1992. MAIN OUTCOME MEASURES: Objects removed from children's aerodigestive tracts were characterized by location, procedure for removal, and type. Objects causing death were characterized by type, shape, and consistency. Three-dimensional objects that had caused asphyxiation were analyzed by computer-simulated models. RESULTS: Of the 165 children treated by endoscopy, 69% were 3 years of age or younger. Foreign bodies most often ingested or aspirated were food (in 36 children) and coins (in 60 children). Of 449 children whose deaths after aspirating foreign bodies were reported to the CPSC, 65% were younger than 3 years. Balloons caused 29% of deaths overall. Conforming objects such as balloons caused a significantly (P < .001) higher proportion of deaths in those aged 3 years or older (60%) vs those younger than 3 years (33%). Of the 101 objects causing deaths that we could analyze, 14 met current standards for use by children of any age. CONCLUSIONS: Balloons pose a high risk of asphyxiation to children of any age. Changes in regulations regarding products intended for children's use might have prevented up to 14 (14%) of 101 deaths in this study.

Adolescent↗
PubMed1995

Head and neck manifestations of Beckwith-Wiedemann syndrome.

Beckwith-Wiedemann syndrome is a congenital disorder manifested by organomegaly, omphalocele, hypoglycemia, and macroglossia. We have found a significant number of these children to be at risk for upper airway obstruction during infancy or childhood. In this review of 13 children, 2 required tracheotomy during infancy for cor pulmonale caused by macroglossia. Seven of nine children older than 1 year required tonsillectomy and adenoidectomy to relieve upper airway obstruction. Although macroglossia can be a cause of airway obstruction in infants with Beckwith-Wiedemann syndrome, we have found that airway obstruction during childhood is related to tonsillar and adenoidal hypertrophy and not to macroglossia. Anterior tongue reduction is reserved for the correction of malocclusion, articulation errors, or cosmesis, whereas tonsillectomy and adenoidectomy may be curative of obstructive symptoms.

Adenoidectomy↗
PubMed1995

Adult respiratory papillomatosis: human papillomavirus type and viral coinfections as predictors of prognosis.

Pathologic material and the records of 29 patients with laryngeal papillomatosis were reviewed. The relationship between the type of human papillomavirus (HPV) and the presence of viral coinfections was correlated with clinical outcome. Using polymerase chain reaction, paraffin-embedded specimens were analyzed for the presence of HPV, Epstein-Barr virus (EBV), cytomegalovirus (CMV), and herpes simplex virus (HSV). The HPV type could be identified in 24 patients' specimens. Twenty-one patients were infected with HPV type 6. The other 3 were infected with HPV type 11 or 16. Three patients developed squamous cell carcinoma, of whom 2 had HPV type 11 or 16. We found HSV, EBV, and CMV in 50%, 12.5%, and 0% of specimens, respectively. An aggressive clinical course was observed in 17 patients. Evidence of coinfection with other viruses was identified in 11 (65%) of these patients. In contrast, a benign clinical course was observed in 7 patients, of whom 2 (29%) had viral coinfections. We conclude that the HPV type and the presence of viral coinfections may be predictive of an aggressive clinical course.

Adult↗
PubMed1995

Diagnosis and management of pediatric tracheal stenosis.

Pediatric tracheal stenosis is a difficult problem that requires very careful preoperative evaluation and classification. Most forms of extrinsic compression are vascular in origin but can be associated with tracheomalacia, complete tracheal rings, and other anomalies of the aerodigestive tract. Optimally, both the vascular malformation and the intrinsic tracheal malformation should be repaired at the same procedure. Long tracheal stenosis, most commonly caused by complete tracheal rings, is best treated by pericardial patch tracheoplasty or cartilage augmentation. Areas of short-segment intrinsic stenosis can sometimes be corrected endoscopically with or without intraluminal stenting, depending on severity. When endoscopic methods fail, resection with end-to-end anastomosis is the procedure of choice for short-segment stenosis.

Anastomosis, Surgical↗
PubMedDate not supplied

Porcine model of airway mucosal injury.

PURPOSE: The development of a reliable animal model of laryngeal or tracheal stenosis has been limited by lack of reproducibility, high morbidity and mortality, and cumbersome technique. The small size of previously proposed models has limited the development of innovative reconstructive techniques. MATERIALS AND METHODS: Eleven of 15 post-weanling commercial piglets underwent injury by a sharpened metal rod to the anterior half of the subglottic region at repeated intervals under endoscopic guidance. Four of 15 animals did not undergo injury and served as control for normal subglottic growth over time. Each airway was sized by endotracheal tube (ETT) passage and endoscopic photography over time, and the degree of total stenosis was estimated in comparison to the control animals. RESULTS: The first two animals underwent daily injury and expired from copious granulation tissue. Eight additional animals developed symptomatic subglottic stenosis manifested by audible stridor and intercostal retractions while undergoing injury every third day. Photographs documented the size of the stenosis to be greater than 50% (40% by ETT sizing) with a mean of three injuries in a mean time of 18 days. CONCLUSION: The porcine model shows a high degree of tolerance with minimal morbidity and consistent reliable results in an animal model of airway stenosis that is suitable for further innovative studies.

Animals↗