Vocal fold paralysis following surgical ductal closure in extremely low birth weight infants: a case series of feeding and respiratory complications

Dysphagia Outcomes Following Surgical Management of Unilateral Vocal Fold Immobility in Children: A Systematic Review

OBJECTIVE

To assess dysphagia outcomes following surgical management of unilateral vocal fold immobility in children.

DATA SOURCES

Ovid Medline, Embase, Web of Science, and CENTRAL databases.

REVIEW METHODS

A systematic review of the medical literature was performed following the PRISMA guidelines. An a priori protocol was defined to identify all articles that presented quantifiable outcome data in children aged <18 years who underwent surgical treatment to improve glottal competence for dysphagia. Two authors independently determined references meeting the inclusion criteria, extracted data, and assigned levels of evidence. Data were pooled via a random effects model where possible. The quality of studies was graded with the MINORS criteria.

RESULTS

An overall 398 publications were screened, with 9 meeting inclusion criteria. A total of 115 patients were included. Of these, 75% had preoperative swallowing symptoms. Surgical intervention for dysphagia included 61 injection laryngoplasties, 11 medialization laryngoplasties, and 10 reinnervations (ansa cervicalis to recurrent laryngeal nerve). The articles consistently reported success in improving dysphagia symptoms, and limited meta-analysis demonstrated a mean improvement after surgical intervention in 79% (95% CI, 67%-91%) of children. The reported rate of minor and major complications was 15% (95% CI, 1%-29%). The MINORS scores ranged from 5 to 12.

CONCLUSION

Surgical management of unilateral vocal fold immobility in properly selected children can be an effective treatment for dysphagia when symptoms are present. Selection of surgical modalities relies on patient- and surgeon-related factors, and the rate of success is high across different interventions in treating these complex children.

The incidence of recurrent laryngeal nerve injury resulting in vocal cord paralysis following interventional congenital catheterisation procedures

BACKGROUND

Recurrent laryngeal nerve injury leading to vocal cord paralysis is a known complication of cardiothoracic surgery. Its occurrence during interventional catheterisation procedures has been documented in case reports, but there have been no studies to determine an incidence.

OBJECTIVE

To establish the incidence of left recurrent laryngeal nerve injury leading to vocal cord paralysis after left pulmonary artery stenting, patent ductus arteriosus device closure and the combination of the procedures either consecutively or simultaneously.

METHODS

Members of the Congenital Cardiovascular Interventional Study Consortium were asked to perform a retrospective analysis to identify cases of recurrent laryngeal nerve injury after the aforementioned procedures. Twelve institutions participated in the analysis. They also contributed the total number of each procedure performed at their respective institutions for statistical purposes.

RESULTS

Of the 1337 patients who underwent left pulmonary artery stent placement, six patients (0.45%) had confirmed vocal cord paralysis. 4001 patients underwent patent ductus arteriosus device closure, and two patients (0.05%) developed left vocal cord paralysis. Patients who underwent both left pulmonary artery stent placement and patent ductus arteriosus device closure had the highest incidence of vocal cord paralysis which occurred in 4 of the 26 patients (15.4%). Overall, 92% of affected patients in our study population had resolution of symptoms.

CONCLUSION

Recurrent laryngeal nerve injury is a rare complication of left pulmonary artery stent placement or patent ductus arteriosus device closure. However, the incidence is highest in patients undergoing both procedures either consecutively or simultaneously. Additional research is necessary to determine contributing factors that might reduce the risk of recurrent laryngeal nerve injury.

Long‐term Outcomes of Vocal Fold Paralysis Following Patent Ductus Arteriosus Ligation in Neonates

INTRODUCTION

In patients undergoing patent ductus arteriosus (PDA) ligation there is a significant risk of left vocal fold paralysis (LVFP) particularly in premature neonates who are small for gestational age. The objective of this study is to determine the incidence of LVFP in infants following PDA ligation and report on long-term outcomes in patients with LVFP.

METHODS

We performed a prospective study of patients undergoing PDA ligation in the newborn intensive care unit (NICU) between April 2004 and May 2014. Following PDA ligation, flexible laryngoscopy was performed to assess vocal fold mobility. Patients were then followed longitudinally to determine long-term outcomes.

RESULTS

A total of 163 infants underwent PDA ligation. Thirty-six patients (22%) developed LVFP following the procedure. Twenty-five percent of neonates <1500 g experienced LVFP versus 5% of patients >1500 g (p = 0.033). Patients with LVFP were more likely to require a feeding tube (64% vs. 19.6%; p < 0.05) and spent more time in the NICU (135 days vs. 106 days; p < 0.05). Twenty-four patients received long-term follow-up. Six (25%) had complete resolution of LVFP, 10 (42%) were compensated, and 8 (33%) demonstrated persistent LVFP with no improvement.

CONCLUSIONS

The incidence of LVFP after PDA ligation is high especially in extremely low birth weight children. The majority of patients recovered well with time, but further surgical intervention was required in uncompensated cases. Long-term follow-up of these patients is needed to ensure improvement. Laryngoscope, 133:1257-1261, 2023.

Outpatient Respiratory Management of Infants, Children, and Adolescents with Post-Prematurity Respiratory Disease: An Official American Thoracic Society Clinical Practice Guideline

Background: Premature birth affects millions of neonates each year, placing them at risk for respiratory disease due to prematurity. Bronchopulmonary dysplasia is the most common chronic lung disease of infancy, but recent data suggest that even premature infants who do not meet the strict definition of bronchopulmonary dysplasia can develop adverse pulmonary outcomes later in life. This post-prematurity respiratory disease (PPRD) manifests as chronic respiratory symptoms, including cough, recurrent wheezing, exercise limitation, and reduced pulmonary function. This document provides an evidence-based clinical practice guideline on the outpatient management of infants, children, and adolescents with PPRD. Methods: A multidisciplinary panel of experts posed questions regarding the outpatient management of PPRD. We conducted a systematic review of the relevant literature. The Grading of Recommendations, Assessment, Development, and Evaluation approach was used to rate the quality of evidence and the strength of the clinical recommendations. Results: The panel members considered the strength of each recommendation and evaluated the benefits and risks of applying the intervention. In formulating the recommendations, the panel considered patient and caregiver values, the cost of care, and feasibility. Recommendations were developed for or against three common medical therapies and four diagnostic evaluations in the context of the outpatient management of PPRD. Conclusions: The panel developed recommendations for the outpatient management of patients with PPRD on the basis of limited evidence and expert opinion. Important areas for future research were identified.

Short-Term Complications Associated with Surgical Ligation of Patent Ductus Arteriosus in ELBW Infants: A 25-Year Cohort Study

OBJECTIVE

This article aims to determine the incidence of short-term complications of surgical patent ductus arteriosus (PDA) ligations, the factors associated with those complications, and whether complications are associated with poor long-term outcomes.

STUDY DESIGN

Retrospective cohort study of all extremely low birth weight (ELBW, < 1,000 g) infants who underwent surgical PDA ligation at a single-center neonatal intensive care unit from 1989 to 2015. Demographic, clinical, and laboratory data were reviewed. The primary outcome was development of a short-term (< 2 weeks from ligation) surgical complication. Secondary outcomes include bronchopulmonary dysplasia (BPD), length of stay, and mortality.

RESULTS

A total of 180 ELBW infants were included; median gestational age and birth weight was 24 weeks and 683 g, respectively, and 44% of infants had at least one short-term complication. Need for vasopressors (33%) was the most common medical complication and vocal cord paralysis (9%) was the most common surgical complication. Younger corrected gestational age at time of repair was associated with increased risk for complications. Mortality, length of stay, and BPD rates were similar between infants with and without complications.

CONCLUSION

Serious complications were seen in a minority of infants. Additional research is needed to determine if short-term complications are associated with long-term adverse outcomes.

Analysis of Vocal Fold Motion Impairment in Neonates Undergoing Congenital Heart Surgery

Importance

Vocal fold motion impairment (VFMI) is a known risk factor following congenital heart surgery (CHS). The impact of this diagnosis on utilization and outcomes is unknown.

Objective

To evaluate the cost, postprocedure length of stay (PPLOS), and outcomes for neonates with VFMI after CHS.

Design, Setting, and Participants

A cross-sectional analysis of the 2012 Kids' Inpatient Database (KID) of neonates who underwent CHS was carried out. The KID is an administrative data set of patients, aged 20 years or younger, and contains data on more than 10 million hospitalizations from 44 states. The KID is limited to inpatient hospitalization and contains discharge summary level of data. Patients were limited to those who were born during the hospitalization and those who were aged 28 days or younger at the time of admission for CHS. A weighted total of 4139 neonates who underwent CHS were identified, of which 3725 survived. The proportion of neonates diagnosed with VFMI was 264 (6.92%) of 3725.

Exposures

Congenital heart surgery.

Main Outcomes and Measures

Cost of inpatient hospital stay, postprocedure length of stay, odds of pneumonia, gastrostomy tube placement, and tracheostomy tube placement. Risk-adjusted generalized linear models examined differences in cost and PPLOS between neonates who underwent CHS and were diagnosed with VFMI and those who were not. Risk-adjusted logistic regression compared the odds of selected outcomes (gastrostomy, tracheostomy, pneumonia). Models were weighted to provide national estimates.

Results

Of 3725 neonates (aged 0-28 days), 2203 (59.1%) were male and 1517 (40.7%) were female. Neonates diagnosed with VFMI had significantly higher total cost by $34 000 (95% CI, 2200-65 000) and PPLOS by 9.1 days (95% CI, 4.6-13.7) compared with those who did not. When PPLOS was included as a covariate in the model for cost, presence of VFMI was no longer significant. There were no differences in odds of pneumonia, gastrostomy, or tracheostomy.

Conclusions and Relevance

Vocal fold motion impairment after CHS was associated with significant increases in cost owing to increased PPLOS. These findings provide a foundation to further investigate standardized screening for VFMI following CHS; early identification and treatment may decrease cost and PPLOS.

Cadaveric Measurements of the Left Recurrent Laryngeal Nerve, Ligamentum Arteriosum, Aortic Arch, and Pulmonary Artery in the Thorax with Clinical Implications and Comparison Between Two Sexes in the American Population

The left recurrent laryngeal nerve (RLN) is prone to get compressed or damaged, leading to vocal cord palsy, due to pathologies or surgeries of the structures closely surrounding this nerve in the thorax, including the esophagus, aortic arch, pulmonary trunk, and ligamentum arteriosum. We wanted to provide a data set including nerve diameter, its distance from the esophagus, measurements of the pulmonary artery, aorta, and ligamentum arteriosum in close proximity of the nerve in a healthy population to avoid its damage during surgery and predict its chances of compression during the diseased condition. We measured the left RLN and the surrounding structures in 39 well-embalmed cadavers. We compared the values among the male and female cadavers. We found that the mean diameter of the left RLN was 1.75 mm, the mean distance of the nerve from esophagus was 9.88 mm, the mean diameters of the aortic arch and pulmonary artery just distal to the attachment of the ligamentum arteriosum were 26.14 and 19.93 mm, respectively, and the length and width of ligamentum arteriosum were 15.89 and 2.79 mm, respectively. No clinically significant differences were found between male and female parameters. This set of values might be useful while investigating the cause of vocal cord palsies or during surgeries in close proximity to left RLN to avoid its damage.

Neonatal vocal fold motion impairment after complex aortic arch reconstruction: What should parents expect after diagnosis?

OBJECTIVES

To study the incidence, sequelae, follow up, and recovery rate of vocal fold motion impairment (VFMI) after complex aortic arch reconstruction in neonates.

STUDY DESIGN

Retrospective case control study.

METHODS

We retrospectively evaluated 105 neonates who underwent complex aortic arch reconstruction from 2014 to 2016. We compared patients that did have VFMI compared to a control group of patients with normal vocal fold movement. Descriptive statistics were computed for all demographic and clinical variables by treatment group.

RESULTS

36% of patients were evaluated for VFMI (n = 38) by an otolaryngologist. The incidence of VFMI was 22% (n = 23). Females were more likely to have VFMI (p = 0.02). Aspiration was more common in patients with VFMI (p = 0.006). The difference in age, weight, incidence of pneumonia, nasogastric tube, gastrostomy, total length of stay, genetic anomaly, and reintubation was not significant between the VFMI group and control group (p > 0.05). Tracheostomy was not performed in any patients with unilateral paralysis. Only 61% of patients followed up in clinic (n = 14). 64% of patients showed improvement or resolution (n = 9). Average time to improvement was 4.8 months. Average time to complete resolution was 10.5 months.

CONCLUSIONS

VFMI after complex aortic arch reconstruction is relatively common. Despite increased aspiration in patients with VFMI, pneumonia did not occur at all in either group. Tracheostomy was not necessary in any patients with a unilateral paralysis. Most patients showed an improvement in the VFMI within 5 months of surgery. Our data support the need for otolaryngology follow-up after the diagnosis of VFMI.

[Left vocal cord paralysis after patent ductus arteriosus surgery]

INTRODUCTION

Patent ductus arteriosus (PDA) is a common problem in preterm newborns. Left vocal cord paralysis (LVCP) can complicate surgical closure if the recurrent nerve is damaged.

MATERIALS AND METHODS

A retrospective case series study was conducted on preterm babies diagnosed with PDA in our unit from 1999 to 2013. Their clinical features and treatment complications were reviewed. In those patients that received surgical treatment a telephone questionnaire on the symptoms of LVCP symptoms was completed, and laryncoscopy examination offered.

RESULTS

A total of 88 subjects diagnosed with PDA were found, of whom 13.64% (12/88) needed surgery. These patients had a lower gestational age and birth weight. They required mechanical ventilation more frequently, and they had more complications such as, diaphragmatic paralysis, bronchopulmonary dysplasia and intraventricular hemorrhage. One third (3/9) of the surgically treated patients had LVCP, and all of them had dysphonia (100% vs. 16.7%, p=.05).

DISCUSSION

LVCP is a common complication of PDA surgery. Further studies are needed to determine its risk factors and its short and long-term consequences.

Vocal cord paralysis and Dysphagia after aortic arch reconstruction and Norwood procedure

OBJECTIVES

To determine the incidence of vocal cord (VC) paralysis and dysphagia after aortic arch reconstruction, including the Norwood procedure.

SETTING

Tertiary children's hospital.

STUDY DESIGN

Retrospective cohort.

METHODS

Database/chart review of neonates requiring Norwood or arch surgery between January 2005 and December 2012. Demographics, postoperative VC function, dysphagia, need for gastrostomy tube and/or tracheotomy, and long-term follow-up were reviewed.

RESULTS

One hundred fifty-one consecutive subjects (96 Norwood, 55 aortic arch) were reviewed. Median age at repair was 9 days (interquartile range [IQR], 7-13) for Norwood and 24 days (IQR, 12-49) for arch reconstruction (P < .001). Documentation of VC motion abnormality was found in 60 of 104 (57.6%) subjects and unavailable in 47 (16 without documentation and 31 who died prior to extubation). There were no significant differences in proportions of documented VC motion (P = .337), dysphagia (P = .987), and VC paralysis (P = .706) between the arch and Norwood groups. Dysphagia was found in 73.5% of Norwood and 69.2% of arch subjects who had documented VC paralysis. Even without unilateral VC paralysis (UVCP), dysphagia was present (56% Norwood, 61% arch). Overall, 120 of 151 (79.5%) required feeding evaluation and a modified feeding regimen. Gastrostomy was required in 31% of Norwood and 23.6% of arch reconstruction overall. To date, mortality in this series is 55 of 151 (36.4%) patients. Of those with VC paralysis, only 23 (22%) had any otolaryngology follow-up after discharge from surgery. More than 75% with VC paralysis with follow-up after hospital discharge had persistent VC paralysis 11.5 months after diagnosis.

CONCLUSION

There is high incidence of UVCP and dysphagia after Norwood and arch reconstruction. Dysphagia was highly prevalent in both groups even without UVCP. Preoperative discussion on vocal cord function and dysphagia should be considered.

Clinical pharmacology of indomethacin in preterm infants: implications in patent ductus arteriosus closure

Indomethacin is a non-steroidal anti-inflammatory drug that is a potent inhibitor of prostaglandin E(2) synthesis. After birth, the ductus arteriosus closes spontaneously within 2-4 days in term infants. The major factor closing the ductus arteriosus is the tension of oxygen, which increases significantly after birth. Prostaglandin E(2) has the opposite effect to that of oxygen; it relaxes smooth muscle and tends to inhibit the closure of the ductus arteriosus. In preterm infants with respiratory distress syndrome, the ductus arteriosus fails to close (patent ductus arteriosus [PDA]) because the concentration of prostaglandin E2 is relatively high. PDA occurs in more than 70 % of neonates weighing less than 1,500 g at birth. The aim of this article was to review the published data on the clinical pharmacology of indomethacin in preterm infants in order to provide a critical analysis of the literature and a useful tool for physicians. The bibliographic search was performed electronically using the PubMed and EMBASE databases as search engines and February 2012 was the cutoff point. A remarkable interindividual variability was observed for the half-life (t(½)), clearance (CL), and volume of distribution (V(d)) of indomethacin. Prophylactic indomethacin consists of a continuous infusion of low levels of indomethacin and may be useful in preterm infants. Extremely preterm infants are less likely to respond to indomethacin. Infants with a postnatal age of 2 months do not respond to treatment with indomethacin. Indomethacin has several adverse effects, the most common of which is renal failure. An increase in serum creatinine of ≥0.5 % mg/dL after indomethacin was observed in about 10-15 % of the patients and creatinine returns to a normal level about 1 week after cessation of therapy. Indomethacin should be administered intravenously by syringe pump for at least 30 min to minimize adverse effects on cerebral, gastrointestinal, and renal blood flow velocities. A prolonged course of indomethacin appears to reduce the risk of severe intracranial hemorrhage and renal impairment in patients with PDA. In conclusion, indomethacin is a useful drug to treat PDA.

Unilateral laryngeal paralysis subsequent to surgical ligation of a patent ductus arteriosus in an 8-week-old domestic shorthair cat

CASE DESCRIPTION

An 8-week-old female domestic shorthair cat was treated for patent ductus arteriosus (PDA) with surgical ligation. Seven weeks postoperatively, the cat was evaluated because of increased upper respiratory noise, inspiratory stridor, wheezing, and episodes of intermittent open-mouth breathing that had developed 1 week following the surgical ligation.

CLINICAL FINDINGS

The cat was sedated, and examination of the larynx revealed left-sided laryngeal paralysis.

TREATMENT AND OUTCOME

At the time left-sided laryngeal paralysis was diagnosed, the clinical signs of laryngeal dysfunction were not considered severe enough to warrant surgical intervention. No treatment was administered, and the owner monitored the cat for respiratory distress and worsening of clinical signs for an additional 5 months. During those 5 months, the clinical signs improved but persisted. Seven months after PDA ligation, the cat was again sedated and the larynx examined. The examination revealed persistent left arytenoid dysfunction, which was believed to be the result of permanent damage to the recurrent laryngeal nerve that was sustained during the surgical ligation of the PDA. The owner was counseled about surgical and medical treatment options for laryngeal paralysis but elected to forego treatment at that time.

CLINICAL RELEVANCE

Unilateral laryngeal paralysis caused by iatrogenic damage to the recurrent laryngeal nerve is a potential complication subsequent to surgical ligation of a PDA. The frequency of iatrogenically induced laryngeal paralysis is likely underestimated in small animal patients. Laryngoscopy should be performed in any small animal with a history of PDA attenuation and clinical signs of respiratory tract disease.

Vocal cord paralysis post patent ductus arteriosus ligation surgery: risks and co-morbidities

OBJECTIVES

1. To determine the prevalence of left vocal cord paralysis (LVCP) post patent ductus arteriosus (PDA) ligation at a Tertiary Care Centre. 2. To identify risk factors associated with LVCP. 3. To identify co-morbidities associated with LVCP. 4. To determine the frequency of pre- and post-operative nasopharyngolaryngoscopic (NPL) examination in this patient population.

METHODS

Retrospective chart review of all infants who underwent PDA ligation surgery at a tertiary care academic hospital between July 2003 and July 2010. Data on patient age, gender, weight, method of PDA ligation, and results of NPL scoping were collected, as well as patient co-morbidities post PDA ligation.

RESULTS

One hundred and fifteen patients underwent PDA ligation surgery. Four patients were excluded due to bilateral vocal cord paralysis. Of the remaining 111 patients, nineteen patients (17.1%) were found to have LVCP. Low birth weight was identified as a significant risk factor for LVCP (p=0.002). Gastroesophageal reflux was identified as a significant co-morbidity associated with LVCP post PDA ligation (p=0.002). Only 0.9% of patients were scoped pre-operatively, and 27.9% were scoped postoperatively.

CONCLUSIONS

LVCP is associated with multiple morbidities. The authors strongly recommend routine post-operative scoping of all patients post PDA ligation surgery, and preoperative scoping when possible. A prospective study is warranted, in order to confirm the prevalence of LVCP as well as risk factors and associated co-morbidities.

Long-term morbidities associated with vocal cord paralysis after surgical closure of a patent ductus arteriosus in extremely low birth weight infants

OBJECTIVE

Determine associations between left vocal cord paralysis (LVCP) and poor respiratory, feeding and/or developmental outcomes in extremely low birth weight (ELBW) infants following surgical closure of a patent ductus arteriosus (PDA).

STUDY DESIGN

ELBW infants who underwent PDA ligation between January 2004 and December 2006 were identified. We compared infants with and without LVCP following ligation to determine relationships between LVCP and respiratory morbidities, feeding and growth difficulties and neurodevelopmental impairment at 18 to 22-month follow-up. Student's t-test, Fisher's exact test and multivariable regression analyses were used to determine associations.

RESULT

In all, 60 ELBW infants with a mean gestational age of 25 weeks and mean birth weight of 725 g had a PDA surgically closed. Twenty-two of 55 survivors (40%) were diagnosed with LVCP post-operatively. Infants with LVCP were significantly more likely to develop bronchopulmonary dysplasia (82 vs 39%, P=0.002), reactive airway disease (86 vs 33%, P<0.0001), or need for gastrostomy tube (63 vs 6%, P<0.0001).

CONCLUSION

LVCP as a complication of surgical ductal ligation in ELBW infants is associated with persistent respiratory and feeding problems. Direct laryngoscopy should be considered for all infants who experience persistent respiratory and/or feeding difficulties following PDA ligation.

Indomethacin pharmacodynamics are altered by surfactant: a possible challenge to current indomethacin dosing guidelines created before surfactant availability

The effect of surfactant administration for respiratory distress syndrome (RDS) on indomethacin (INDO) pharmacodynamics and dosing requirements for patent ductus arteriosus (PDA) closure and renal toxicity was evaluated. A 22-year prospective cohort study including 442 INDO-treated patients given 466 INDO treatment courses. The database included demographic information, medical problems, and medications. Neonates with a PDA confirmed by echocardiography were treated with INDO, 0.25-0.3 mg/kg. Subsequent INDO dosing was based on a combined pharmacokinetic/pharmacodynamic (PK/PD) approach. Data were fit to an Emax model and ANOVA was used to compare mean closure levels between groups. PDA closure was successful in 405 of 442 patients (91.6%) and in 434 of 466 treatment courses (93.1%) using an individualized PK/PD dosing approach. Renal toxicity was documented in 56 of 442 patients (12.7%) or 56 of 466 treatment courses (12.0%). Patients not treated with synthetic surfactant trended toward lower mean INDO concentrations at PDA closure compared to patients treated with synthetic surfactant (1.65 vs. 2.01 mg/l; P > 0.05) and significantly lower mean INDO concentrations at PDA closure compared to patients treated with natural surfactant (1.65 vs. 2.15 mg/l; P < 0.002). This requires an increased total dose of ~0.3 mg/kg or an individual dose increase of 0.1 mg/kg. Administration of natural or synthetic surfactant for RDS may increase the INDO concentrations and doses needed for PDA closure in premature infants.

Unilateral vocal fold paralysis in premature infants after ligation of patent ductus arteriosus: vascular clip versus suture ligature

OBJECTIVES

We investigated risk factors associated with unilateral iatrogenic vocal fold paralysis (IVFP) in the context of ligation of patent ductus arteriosus (PDA) and compared the rates of paralysis between vascular clip and suture ligation procedures.

METHODS

We performed a prospective examination of infants with isolated PDA treated surgically during 1995 to 2005. Statistical significance was determined with a 2-tailed t-test.

RESULTS

Of 68 PDA ligations, 13 cases of left-sided IVFP were diagnosed, for an overall incidence of 19%. All cases of IVFP occurred in 55 infants who weighed less than 1 kg at birth. Suture ligature was used in 60% of all PDA ligation patients, and vascular clips in 40%. The incidence of IVFP in patients with vascular clips (19%) was similar to the incidence in those with suture ligature (20%). Hoarseness or stridor was present in 69% of patients with IVFP, compared to 17% of normal controls (p <0.001). The rate of aspiration was not increased in the IVFP group; however, 15% of the patients with IVFP had episodes of decreased oxygen saturation, versus 7% of infants with normal vocal fold mobility.

CONCLUSIONS

A hoarse infant with a birth weight of less than 1 kg who has undergone PDA ligation should be examined for unilateral IVFP. Vascular clips and suture ligature are associated with similar rates of IVFP.