Unilateral vocal fold paralysis after congenital cardiothoracic surgery: a meta-analysis.

BACKGROUND AND OBJECTIVE: There is variation in the literature in regard to the occurrence of unilateral vocal fold paralysis (UVFP) after congenital cardiothoracic surgery. The objective of this study was to identify and appraise the evidence for the occurrence of UVFP after congenital cardiothoracic surgery in a meta-analysis. METHOD: A comprehensive search strategy in Medline, Embase, and the Cochrane Library was conducted, limited to English publications. Two independent reviewers screened studies for eligibility criteria. Of the 162 identified studies, 32 (20%) met the inclusion criteria. Using the Oxford Centre for Evidence-Based Medicine guidelines, 2 reviewers appraised the level of evidence, extracted data, and resolved discrepancies by consensus. Weighted pooled proportion and 95% confidence intervals (CIs) are reported. RESULTS: Thirty-two studies (n = 5625 patients) were included. Levels of evidence varied from level 3 to 4. Among all studies, the weighted pooled proportion of UVFP was 9.3% (95% CI, 6.6% to 12.5%), and among 11 studies (n = 584 patients) that postoperatively evaluated patients with flexible nasopharyngolaryngoscopy to document presence of UVFP, the weighted pooled proportion of UVFP was 29.8% (95% CI, 18.5% to 42.5%). Twenty-one studies (n = 2748 patients) evaluated patients undergoing patent ductus arteriosus ligation surgery, and the weighted pooled proportion of UVFP was 8.7% (95% CI, 5.4% to 12.6%). Six of these (n = 274 patients) assessed all patients postoperatively, and the weighted pooled proportion of UVFP was 39% (95% CI, 18% to 63%). Pooled analyses of risk factors and comorbidities are reported. Heterogeneity and publication bias were detected. CONCLUSIONS: UVFP is a demonstrated risk of congenital cardiothoracic surgery. Routine postoperative nasopharyngolaryngoscopy for vocal fold assessment by an otolaryngologist is suggested.

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.

Antibacterial activity of liposomal gentamicin against Pseudomonas aeruginosa: a time-kill study.

Cystic fibrosis (CF) is a common and lethal genetic disorder with a carrier frequency of 1 in 29 Caucasians. Chronic respiratory infections with Pseudomonas aeruginosa are the leading cause of morbidity and mortality in individuals with CF. Aminoglycoside antibiotics, including gentamicin, are highly effective against P. aeruginosa, but severe toxicity limits their use. One potential strategy for avoiding this problem is to encapsulate aminoglycosides in liposomes. In this study, we compared the bactericidal capacity of liposome-encapsulated gentamicin with that of free antibiotic against clinical isolates of P. aeruginosa. Liposome size, encapsulation efficiency and minimal inhibitory concentrations (MICs) of the free and liposomal gentamicin against gentamicin-sensitive and -resistant strains of P. aeruginosa were determined. In vitro time-kill studies were performed using free and liposomal gentamicin at 1, 2 or 4 times the MICs. The average liposomal size was 426.25 +/- 13.56 nm, with a gentamicin encapsulation efficiency of 4.51 +/- 0.54%. The MICs for liposomal gentamicin were significantly lower than those of corresponding free gentamicin. In addition, the time-kill values for liposomal gentamicin were either equivalent to or better than those of the free antibiotic. In conclusion, our liposomal gentamicin formulation is a more potent antipseudomonal drug with an improved killing time and prolonged antimicrobial activity.