Albuterol administration is commonly associated with increases in serum lactate in patients with asthma treated for acute exacerbation of asthma.

BACKGROUND: Controversy exists around the incidence and cause of hyperlactatemia during asthma exacerbations. We evaluated the incidence, potential causes, and adverse events of hyperlactatemia in patients with acute asthma exacerbation. METHODS: This study was a subanalysis of subjects receiving placebo from a prospective, randomized trial evaluating an IV b -adrenergic agonist in acute asthma exacerbation. Plasma albuterol, serum lactate, and bicarbonate concentrations were measured at baseline and 1.25 h, and dyspnea score and spirometry were measured at baseline and hourly for 3 h. All subjects had a therapeutic trial comprising 5 to 15 mg nebulized albuterol, 0.5 to 1 mg nebulized ipratropium, and at least 50 mg oral prednisone or its equivalent prior to initiation of the study. Following randomization, subjects were treated with continued albuterol and IV magnesium at the discretion of their treating physician. Subjects were followed to hospital admission or discharge with follow-up at 24 h and 1 week. RESULTS: One hundred seventy-fi ve subjects were enrolled in the parent trial, with 84 in the placebo group. Sixty-fi ve had complete data. Mean SD albuterol administration prior to baseline was 12.3 5.3 mg. Mean baseline lactate was 18.5 8.4 mg/dL vs 26.5 11.8 mg/dL at 1.25 h ( P , .001). Forty-fi ve subjects (69.2%) had hyperlactatemia. Mean baseline bicarbonate level was 22.6 2.9 mEq/L vs 21.9 4.0 mEq/L at 1.25 h ( P 5 .11). Plasma albuterol concentration correlated with lactate concentration ( b 5 0.45, P , .001) and maintained a significant association after adjusting for asthma severity ( b 5 0.41, P 5 .001). Hyperlactatemia did not increase the risk of hospitalization or relapse ( P 5 .26) or was associated with lower FEV 1 % predicted at 3 h ( P 5 .54). CONCLUSIONS: Plasma albuterol was significantly correlated with serum lactate concentration after adjusting for asthma severity. Hyperlactatemia was not associated with poorer pulmonary function as measured by 3-h FEV 1 % predicted or increased hospitalization or relapse at 1 week.

Outcomes of tricuspid valve repair and replacement: a propensity analysis.

BACKGROUND: The purpose of this study was to compare operative mortality and long-term outcome of patients undergoing tricuspid valve replacement versus tricuspid valve repair. METHODS: From February 1986 to July 2006, 315 patients underwent tricuspid valve surgery including 93 replacements (72 biologic, 21 mechanical) and 222 repairs. To control for selection bias and varying comorbidities, a matched cohort of patients undergoing repair versus replacement was selected using propensity score analysis (68 patients in each group). RESULTS: In the propensity-matched cohorts, operative mortality was similar for tricuspid valve replacement (13% +/- 4%) and repair (18% +/- 5%; p = 0.64). Intensive care unit length of stay was similar between cohorts (replacement, 4 days; repair, 3 days; p = 0.45), but the replacements had a significantly longer hospital lengths of stay (9 days versus 6 days; p = 0.01). In the replacement cohort, survival was 85% at 1 year, 79% at 5 years, and 49% at 10 years. In the repair cohort, survival rates were similar with 80% at 1 year, 72% at 5 years, and 66% at 10 years (p = 0.66 versus replacement). CONCLUSIONS: Surgical treatment of tricuspid valve disease, regardless of the operative approach, is associated with significant early and late mortality. However, there is no difference favoring tricuspid valve repair over replacement. Thus, we should not hesitate to consider tricuspid valve replacement for patients in whom we believe there is a reasonable chance for recurrence of regurgitation after repair.

Isolating the entire posterior left atrium improves surgical outcomes after the Cox maze procedure.

OBJECTIVES: The importance of each ablation line in the Cox maze procedure for treatment of atrial fibrillation remains poorly defined. This study evaluated differences in surgical outcomes of the procedure performed either with a single connecting lesion between the right and left pulmonary vein isolations versus 2 connecting lesions (the box lesion), which isolated the entire posterior left atrium. METHODS: Data were collected prospectively on 137 patients who underwent the Cox maze procedure from April 2002 through September 2006. Before May 2004, the pulmonary veins were connected with a single bipolar radiofrequency ablation lesion (n = 56), whereas after this time, a box lesion was routinely performed (n = 81). The mean follow-up was 11.8 +/- 9.6 months. RESULTS: The incidence of early atrial tachyarrhythmia was significantly higher in the single connecting lesion group compared with that in the box lesion group (71% vs 37%, P < .001). The overall freedom from atrial fibrillation recurrence was significantly higher in the box lesion group at 1 (87% vs 69%, P = .015) and 3 (96% vs 85%, P = .028) months. The use of antiarrhythmic drugs was significantly lower in the box lesion group at 3 (35% vs 58%, P = .018) and 6 (15% vs 44%, P = .002) months. CONCLUSIONS: Isolating the entire posterior left atrium by creating a box lesion instead of a single connecting lesion between the pulmonary veins showed a significantly lower incidence of early atrial tachyarrhythmias, higher freedom from atrial fibrillation recurrence at 1 and 3 months, and lower use of antiarrhythmic drugs at 3 and 6 months. A complete box lesion should be included in all patients undergoing the Cox maze procedure.

Recurrent mitral regurgitation and risk factors for early and late mortality after mitral valve repair for functional ischemic mitral regurgitation.

BACKGROUND: Mortality for patients with coronary artery disease and functional ischemic mitral regurgitation (IMR) remains high regardless of the treatment strategy. Data regarding risk factors, progression of MR, and cause of death in this subgroup are limited. METHODS: A retrospective study was performed on 257 consecutive patients undergoing mitral valve repair exclusively for IMR from 1996 to 2005. Potential preoperative and perioperative risk factors for death and postoperative echocardiographic data were recorded. RESULTS: Preoperative echocardiography demonstrated 3+ to 4+ MR in 98.4% (252 of 257). Concomitant coronary artery bypass grafting was performed in 80.9% (208 of 257). Operative mortality was 10.1% (26 of 257). Overall survival by Kaplan-Meier analysis was 68.3% at 3 years and 52.0% at 5 years. Factors associated with late mortality by multivariate analysis include advanced age (relative risk [RR], 1.037; 95% confidence interval [CI], 1.016 to 1.059; p < or = 0.001), preoperative dialysis (RR, 3.504; 95% CI, 1.590 to 7.720; p = 0.008), and diabetes (RR, 2.047; 95% CI, 1.319 to 3.177; p = 0.001). Echocardiographic data at 20 +/- 25 months were available in 57% (147 of 257). Their survival by Kaplan-Meier analysis was 76.4% at 3 years and 65.1% at 5 years with 0 to 2+ MR postoperatively (n = 106) vs 61.3% and 35.8% with 3+ to 4+ MR (n = 41; p = 0.003). Cause of death was available in 72.3% (60 of 83) of late deaths, with 42.2% (35 of 83) attributed to cardiac causes and 30.1% (25 of 83) noncardiac. CONCLUSIONS: Mortality for IMR remains high despite surgical management and may be related to risk factors for progression of coronary artery disease. Despite repair, MR progresses in many patients and is associated with poor survival, although more detailed prospective data are needed to characterize this relationship.