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Marlyn S Woo

Publications and source records attributed to Marlyn S Woo.

18 recordsLinked to original sources
PubMed2006

Lung transplantation for cystic fibrosis.

PURPOSE OF REVIEW: To examine recent publications on lung transplantation for cystic fibrosis for changes in surgical techniques, selection criteria of patients, and impact on quality of life. RECENT FINDINGS: Recent evidence focuses on cystic fibrosis patient subsets enabling better decisions about listing for lung transplantation as a therapeutic option. There is information about Burkholderia cepacia infection, ventilator dependence, young age, and arthropathy. In the US, the United Network for Organ Sharing has addressed perceived inequities in organ distribution by allocating organs by illness severity rather than time on the waiting list. A Lung Allocation Score ranks severity for patients 12 years of age and older for transplantation based on variables including lung function, oxygen and ventilatory needs, diabetes, weight and physical performance. Some recently studied important variables that influence survival in cystic fibrosis and after lung transplantation, including airway infections, pancreatic exocrine function and acute exacerbations, are not included in the Lung Allocation Score. Few publications have examined quality of life after transplantation, and a definitive work has yet to appear. SUMMARY: New information has refined decision-making about lung transplantation for patients with cystic fibrosis. We examine recent findings and make recommendations for patients, families and medical providers.

Cystic Fibrosis↗
PubMed2005

FMRI responses to hyperoxia in congenital central hypoventilation syndrome.

Congenital Central Hypoventilation Syndrome (CCHS) patients show partial retention of peripheral chemoreception despite impaired ventilatory responses to CO2 and hypoxia. The condition allows examination of central responses to hyperoxia, which minimizes afferent traffic from peripheral chemoreceptors. We used functional magnetic resonance imaging to assess blood oxygen level-dependent signals over the brain during a baseline and subsequent 2-min hyperoxia (100% O2) period in 14 CCHS and 15 control subjects. After partitioning gray matter and correcting for global effects, the images were analyzed using volume-of-interest time trends followed by repeated-measures ANOVA and conventional cluster analyses. Respiratory rates initially (first 20 s) fell in CCHS, but rose in control subjects; CCHS heart rate increased in the first minute, and then decreased in the second minute, as in controls, but with muted rise and extent of decline. Multiple sites within the cerebellum, midbrain, and pons responded similarly to the challenge in both groups. Response patterns differed early in the right amygdala, paralleling initial respiratory pattern deficits, and late in the right insula, concomitant with cardiac rate differences. Signals also differed between groups in the medial and anterior cingulate, hippocampus, head of caudate, and lentiform nuclei, as well as pontine and midbrain structures and regions within the superior temporal and inferior frontal cortical gyri. The findings emphasize that structures that can alter respiratory timing, such as the amygdala, and modulate sympathetic outflow, such as the right insula, are deficient in CCHS. Medullary and pontine areas targeted by PHOX2B expression are also affected.

Adolescent↗
PubMed2004

The necessity of complete CFTR mutational analysis of an infertile couple before in vitro fertilization.

OBJECTIVE: To determine the genotype of a triplet resulted from an IVF procedure, with discordant cystic fibrosis (CF) phenotype. DESIGN: Molecular diagnosis of CF. SETTING: Affected triplet followed at the CF Clinic Center of Children's Hospital Los Angeles was referred to Molecular Genetics Laboratory at Georgetown University Medical Center for comprehensive DNA analysis of the cystic fibrosis transmembrane regulator (CFTR) gene. PATIENT(S): Three affected children and the healthy parents with negative family history of CF. MAIN OUTCOME MEASURE(S): Temporal temperature gradient gel electrophoresis and direct DNA sequencing were used to detect and to identify the mutations. RESULT(S): The child with classic CF had DeltaF508 and R553X mutations. Two children with mild CF symptoms had DeltaF508 and R117C. The father carried two mutations, R553X and R117C. The mother is a carrier for DeltaF508. CONCLUSION(S): Mutational analysis of the CFTR gene should always be recommended to the infertile couples seeking for IVF. The CFTR mutation screening would be essential if the man has congenital bilateral absence of vas deferens (CBAVD) despite the negative family history of CF. Option of complete CFTR gene analysis at a cost of about 1,500-2,000 dollars should be made available if one mutation is found in the male partner with congenital bilateral absence of vas deferens.

Adult↗
PubMed2004

Previous thoracic surgery does not increase peri-operative mortality in pediatric heart-lung transplant recipients.

BACKGROUND: Heart-lung transplant (HLT) is indicated in select children with end-stage cardiopulmonary disease. We sought to determine whether previous thoracic surgery increases peri-operative morbidity and mortality. METHODS: Retrospective data were analyzed using unpaired Student's t-test and Fisher's exact test. Results are reported as mean +/- SD. Peri-operative mortality was defined as death at </=30 days post-transplant. RESULTS: From August 1993 through April 2001, 13 patients (mean age 7.9 +/- 5.3 years; 9 girls, 4 boys) underwent HLT at our center. Eight of 13 (62%) had previous thoracic surgery and 5 of 13 (38%) did not. Interval of last surgery to transplant date was 45.5 +/- 26.4 months (range 6 to 79 months). We compared HLT patients who had previous thoracic surgery to HLT recipients who did not. There was no significant difference in weight (18.6 +/- 14.3 vs 36.5 +/- 20.7 kg, p = 0.09), age (6.5 +/- 4.5 vs 10.2 +/- 6.1 years, p = 0.23) or duration of intubation (14.1 +/- 12.9 vs 17.0 +/- 30.3 days, p = 0.83). There were no caval or tracheal anastomotic stenoses in either group. There was no significant difference in blood products transfused </=48 hours after HLT: packed red blood cells (p = 0.16); fresh frozen plasma (p = 0.13); platelets (p = 0.59), and cryoprecipitate (p = 0.27). There was no difference in cardiopulmonary bypass time (129.3 +/- 48.2 vs 160.6 +/- 73.9 minutes, p 0.39); post-operative diaphragm dysfunction (4 of 8 vs 0 of 5, p = 0.1); re-exploration for bleeding (2 of 8 vs 1 of 5, p = 1.0); or peri-operative mortality (2 of 8 vs 0 of 5, p = 0.48). CONCLUSIONS: We conclude that previous thoracic surgery in HLT recipients does not significantly increase blood product transfusion, cardiopulmonary bypass time or peri-operative mortality.

Adolescent↗
PubMed2004

A decade of living lobar lung transplantation: recipient outcomes.

OBJECTIVE: Living lobar lung transplantation was developed as a procedure for patients considered too ill to await cadaveric transplantation. METHODS: One hundred twenty-eight living lobar lung transplantations were performed in 123 patients between 1993 and 2003. Eighty-four patients were adults (age, 27 +/- 7.7 years), and 39 were pediatric patients (age, 13.9 +/- 2.9 years). RESULTS: The primary indication for transplantation was cystic fibrosis (84%). At the time of transplantation, 67.5% of patients were hospitalized, and 17.9% were intubated. One-, 3-, and 5-year actuarial survival among living lobar recipients was 70%, 54%, and 45%, respectively. There was no difference in actuarial survival between adult and pediatric living lobar recipients (P =.65). There were 63 deaths among living lobar recipients, with infection being the predominant cause (53.4%), followed by obliterative bronchiolitis (12.7%) and primary graft dysfunction (7.9%). The overall incidence of acute rejection was 0.8 episodes per patient. Seventy-eight percent of rejection episodes were unilateral. Age, sex, indication, donor relationship, preoperative hospitalization status, use of preoperative steroids, and HLA-A, HLA-B, and HLA-DR typing did not influence survival. However, patients on ventilators preoperatively had significantly worse outcomes (odds ratio, 3.06, P =.03; Kaplan-Meier P =.002), and those undergoing retransplantation had an increased risk of death (odds ratio, 2.50). CONCLUSION: These results support the continued use of living lobar lung transplantation in patients deemed unable to await a cadaveric transplantation. We consider patients undergoing retransplantations and intubated patients to be at significantly high risk because of the poor outcomes in these populations.

Adolescent↗
PubMed2004

An overview of paediatric lung transplantation.

Paediatric lung transplantation is indicated in selected children with end-stage lung disease that is not amenable to conventional medical or surgical therapy. The indications and complications differ from adult lung transplant patients. Due to the long waiting times for suitable cadaveric lungs, other types of lung transplantation, such as living donor lobar and split-lung procedures, have been utilised in paediatric patients. Unlike adult candidates, cystic fibrosis and primary pulmonary hypertension are the primary indications. Most recipients are in the adolescent age group. Complications that occur with greater frequency in paediatric lung recipients include somatic growth and graft function, post-transplant lymphoproliferative disease and medical non-adherence. While long-term outcome remains similar between adult and paediatric lung transplant recipients, there is a lower risk of bronchiolitis obliterans in very young recipients and in those who receive living donor lobar lung transplantation. Research into these clinical problems is hampered by the fact that only a small number of paediatric transplants are performed at each centre. Hence, improvement in outcome for these children will be dependent on developing methods to produce better tolerance, understanding the mechanisms/treatment of bronchiolitis obliterans and multi-centre studies that focus on the problems that primarily affect the paediatric lung transplant recipient.

Age Factors↗
PubMed2004

A decade of living lobar lung transplantation: perioperative complications after 253 donor lobectomies.

Living lobar lung transplantation places two donors at risk for each recipient. We examined the perioperative outcomes associated with the 253 donor lobectomies performed at our institution during our first decade of living lobar lung transplantation. There have been no perioperative or long-term deaths. 80.2% of donors (n = 203) had no perioperative complications, while fifty (19.8%) had one or more complication. The incidence of intraoperative complications was 3.6%. Complications requiring reoperation occurred in 3.2% of donors. 15.0% of donors had other perioperative complications; the most serious were two donors who developed pulmonary artery thrombosis, while the most common was the need for an additional thoracostomy tube or a thoracostomy tube for >/=14 d for persistent air leaks and/or drainage. Right-sided donors were more likely to have a perioperative complication than left-sided donors (odd ratio 2.02, p = 0.04), probably secondary to right lower and middle lobe anatomy. This experience has shown donor lobectomy to be associated with a relatively low morbidity and no mortality, and is important if this procedure is to be considered an option at more pulmonary transplant centers, given continued organ shortages and differences in philosophical and ethical acceptance of live

Adult↗
PubMed2003

Acute neurological deficits in a young adult with cystic fibrosis.

An abrupt onset of a neurological deficit is a rare occurrence in patients with cystic fibrosis (CF). As many CF patients have indwelling intravenous catheters, one of the complications may be deep venous thrombosis. Cerebral thromboembolism through an intracardiac shunt should be considered in CF patients who develop unexplained acute neurological deficits. We report on the case of a 19-year-old CF patient with insulin-dependent diabetes mellitus who was on oral contraceptives and had a Port-A-Cath(R) in place. The patient developed an acute neurological deficit after pulmonary function testing. Radiologic investigations of her head and neck were unremarkable, except for bilateral maxillary and ethmoid sinusitis. An electroencephalogram showed epileptiform discharges primarily from the right hemisphere. A transthoracic echocardiogram (TTE) revealed a small thrombus in the right atrium. A transesophageal echocardiogram (TEE) demonstrated a left-to-right shunt through a patent foramen ovale (PFO) that was not found by TTE. Extensive investigation to rule out congenital and acquired thrombophilia was negative. Treatment consisted of aspirin and discontinuation of oral contraceptives and vitamin K supplementation. Spontaneous complete recovery of the neurological deficits occurred within 24 hr after onset of symptoms.We conclude that paradoxical embolism should be in the differential diagnoses of CF patients who have indwelling intravenous catheters and who develop an unexplained stroke. An extensive investigation to rule out intracardiac abnormalities and thrombophilia should be considered. The risks and benefits of PFO closure vs. prophylactic anticoagulant and antiplatelet aggregation treatment in this group of patients should be carefully weighed.

Adult↗
PubMed2003

What are the best pulmonary function test parameters for early detection of post-lung transplant bronchiolitis obliterans syndrome in children?

Post-lung transplant bronchiolitis obliterans syndrome (BOS) is defined as an unexplained fall in forced expiratory volume in 1 s (FEV1) >or=20% of baseline (B). There have been reports in adults that FEF25-75% (>30% decline from B) is more sensitive than FEV1 for the early diagnosis of BOS. Yet, it is not known if other pulmonary function test (PFT) parameters - forced expiratory flow rates at 25-75% of vital capacity (FEF25-75%) and maximal expiratory flow rate at 80% (Vmax80%), 70% (Vmax70%) and 60% (Vmax60%) - are more sensitive indicators for early diagnosis of BOS than FEV1 in post-lung transplant children. We reviewed serial PFTs of 18 patients (ages 14.1 +/- 3.7 yr, 50% female) who had lung transplantation at our institution from 1993 to 1999, and who met the criteria for BOS diagnosis. There was no significant difference in post-transplant days when decline in FEV1 >or=20% of B, FEF25-75% >30% of B, and Vmax80%, Vmax70% and Vmax60% from normal occurred (635 +/- 431, 551 +/- 422 and 454 +/- 287 days, respectively; p = 0.4). However, a decline in FEV1 was the first abnormality in only 39% of the patients, while a decline in FEF25-75% and Vmax at specific lung volume were the first abnormality in 78% and 56% of the patients, respectively. The earliest signs of BOS would be missed in 61% of patients if FEV1 was the primary parameter used for the diagnosis. In order to improve the sensitivity of the diagnosis of post-lung transplant BOS; we speculate that the diagnosis should be based on decreases in FEF25-75% rather than on FEV1.

Adolescent↗
PubMed2003

Bordetella bronchiseptica infection in pediatric lung transplant recipients.

Bordetella bronchiseptica are small, pleomorphic Gram-negative coccobacilli which are commensal organisms in the upper respiratory tract of many wild and domestic animals ('kennel cough' in dogs). While it is common for health care providers to ask about exposure to ill family/friends, most do not routinely inquire about the health or immunization status of household pets. We report two cases of B. bronchiseptica pneumonia in lung transplant recipients [cystic fibrosis (CF); ages 10 and 15 yr; one male] who contracted B. bronchiseptica from pet dogs. We compared their course and outcome to four children (two CF, one congenital heart disease and one Duchenne's muscular dystrophy; four males, age range 6 months to 14 yr) with B. bronchiseptica cultured from the respiratory tract. Two of the four patients also acquired their illnesses from pet dogs and two from unknown sources. One lung transplant recipient expired from progressive respiratory failure. We conclude that B. bronchiseptica can cause serious infections in both immunosuppressed and immunocompetent children. We speculate that a detailed history of exposure to ill pets (particularly dogs), and the immunization status of all pets should be included in the routine evaluation of all pediatric transplant recipients.

Adolescent↗
PubMed2002

Clinical findings and lung pathology in children with cystic fibrosis.

Cystic fibrosis pulmonary disease is assessed by pulmonary function tests, arterial blood gases, and chest X-rays, but the correlation with lung pathology is unknown. We reviewed the clinical findings and lung pathology of 21 cystic fibrosis patients who had lung transplant. Pulmonary function tests, Brasfield scores, arterial blood gases, and age were correlated with lung pathology. All patients had severe Brasfield scores (9.0 +/- 3.2), airways obstruction (FEV1 25.6 +/- 5.6% predicted, FEF(25-75%) 11.0 +/- 4.5% predicted), and hyperinflation (residual volume [RV] 341.8 +/- 75.8% predicted). All patients were hypoxemic (PO2 64.2 +/- 8.2 mm Hg), and 5 of 21 (24%) were hypercapneic (PCO2 > 50 mm Hg). Pulmonary function tests and Brasfield scores were within a narrow range, and did not allow correlation with lung pathology. Small airway density (airways < 2 mm/cm2) decreased with increasing age. There were no differences in small airways inflammation and fibrous narrowing between the hypercapneic and nonhypercapneic patients, but the percent of smallest airways (airways < 0.35 mm) was significantly lower in the hypercapneic group. We conclude that there is significant correlation between airway pathology and increased age and CO2 retention. We speculate that decreased small airway density in older patients and the decreased proportion of smallest airways in hypercapneic patients is caused by increased dilatation of small airways.

Adolescent↗
PubMed2002

Correlation between digital clubbing and pulmonary function in cystic fibrosis.

The correlation between digital clubbing and certain pulmonary function derangements (hypoxemia and FEV(1)) was previously described. However, the relationship between digital clubbing and other measures of pulmonary function or the presence of liver disease in patients with cystic fibrosis (CF) is poorly defined. Hence we compared the digital clubbing index (CI: ratio of distal phalangeal depth to interphalangeal depth) of 100 patients with CF (43 males, 57 females; mean age, 15.7 +/- 7.3 years) with that of 100 age- and gender-matched healthy controls. Digital clubbing was defined as a CI > or = 1.00 (mean + 2.6 SD; 99% of normal subjects). The CI and its relationship to pulmonary function and to liver disease was then evaluated in the CF patients. Digital clubbing was present in 75/100 (75%) of CF patients but was absent in all controls (P < 0.0001). In CF patients, CI was inversely correlated with PaO(2) (r = -0.555; P < 0.001), FEV(1) (r = -0.499; P < 0.001), and FEF(25-75%) (r = -0.404; P < 0.001), and was positively correlated with RV (r = 0.285; P < 0.05) and the slope of phase 3 of single-breath nitrogen washout (SP3N(2)) (r = 0.532; P < 0.01). There was no significant correlation between CI and age (r = 0.020; P = 0.84), TLC (r = -0.097; P = 0.34), PaCO(2) (r = 0.167; P = 0.10), or history of liver disease (P = 0.08). We conclude that in CF, the degree of digital clubbing is related to degree of hypoxemia, airways obstruction, hyperinflation, and nonuniformity of ventilation.

Adolescent↗
PubMed2002

Does lung growth occur when mature lobes are transplanted into children?

Lung volume increases after living donor lobar lung transplantation (LD) in children. The mechanism responsible for this increase may be alveolarization (lung growth) or alveolar dilation. The diffusing capacity of the lung for carbon monoxide adjusted for lung volume (DLco/VA) should decrease if alveolar dilation occurs, but not if lung growth occurs. Pulmonary function tests were measured 1-12 months after transplant in 20 children receiving LD transplants and in 11 children receiving cadaveric whole lung transplantation (CL). One month after transplant there were no differences between LD and CL recipients in age, gender, or height. Compared to the first month after transplant, height increased at 6-12 months after LD (p < 0.05), and only at 12 months after CL (p = 0.02). Total lung capacity (TLC) showed an 11-22% increase at 3-12 months after LD, and an 11-14% increase at 6-12 months after CL. DLco/VA showed an 11-17% decrease at 3-12 months after LD. However, in recipients of CL, DLco/VA showed a transient decrease of 10% at 3-6 months post-transplant, but was not significantly lower at 9-12 months. LD recipients had lower DLco/VA values than CL recipients at 6-12 months after transplant (p < 0.05). We conclude that following LD, lung volume increases, but DLco/VA decreases. We speculate that alveolar dilation, rather than alveolarization, is the primary mechanism of increased lung volume in children following LD.

Adolescent↗
PubMed2002

Pediatric recipients of living donor lobar lung transplants: postoperative care.

Bilateral living donor lobar lung transplantation is a treatment option for selected children and adults with end-stage lung disease. Careful donor evaluation, skilled intraoperative management and surgical technique, and diligent immediate postoperative care and follow-up all contribute to better outcomes. Although medical management of whole lung transplant recipients in the immediate postoperative period is similar to that of lobar lung transplant recipients, there are specific differences. Anatomical distinctions, such as the entire cardiac output flowing to 2 lobes instead of 5, and thoracic space issues with simultaneous mechanical ventilation and chest tube suction, contribute to these differences. Early postoperative care, including initial postoperative stabilization, ventilation, fluid management, rejection/infection surveillance and prophylaxis, and beginning rehabilitation, can be adapted to ensure successful outcomes in these patients.

Adolescent↗