ABSTRACT
Cardiac output during cardiac catheterization is often estimated using the modified Fick method (COFick). In this proof-of-concept, prospective non-randomized study carried out in a single academic healthcare centre, we examined whether replacing COFick in the Gorlin formula with Cheetah-NICOM monitor cardiac output (COCheetah) could produce an accurate and precise estimate of aortic valve area in patients with severe aortic stenosis. In twenty-six subjects, COFick and COCheetah were obtained concurrently. A spot and 3-minute running average of COCheetah was used. Bland and Altman analysis was used to derive bias, 95% limits of agreement (LOA) and confidence intervals (CI). The mean difference (bias) between AVACheetah (average) and AVAFick was 0.11 cm2 and the 95% LOA were ±0.42 cm2. The 95% CI of the bias was 0.02-0.2 cm2. The bias and 95% LOA of AVACheetah (spot value) were 0.14 ± 0.42cm2, with a 95% CI of 0.06-0.23 cm2. No proportional bias was present. AVACheetah thus appears to be a reasonably accurate measure of AVA in patients with severe aortic stenosis compared to AVAFick measured using a modified Fick CO. However, the limits of agreement were not narrow enough to consider AVACheetah and AVAFick interchangeable.
Subject(s)
Aortic Valve/physiology , Cardiac Output , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Pilot ProjectsABSTRACT
AIMS: The clinical effectiveness of buprenorphine-naloxone (bup-nx) and clonidine for opioid detoxification in in-patient and out-patient community treatment programs was investigated in the first studies of the National Institute of Drug Abuse Clinical Trials Network. DESIGN: Diagnostic and Statistical Manual version IV (DSM IV)-diagnosed opioid-dependent individuals seeking short-term treatment were randomly assigned, in a 2 : 1 ratio favoring bup-nx, to a 13-day detoxification using bup-nx or clonidine. METHODS: A total of 113 in-patients (77 bup-nx, 36 clonidine) and 231 out-patients (157 bup-nx, 74 clonidine) participated. Supportive interventions included appropriate ancillary medications and standard counseling procedures guided by a self-help handbook. The criterion for treatment success was defined as the proportion of participants in each condition who were both retained in the study for the entire duration and provided an opioid-free urine sample on the last day of clinic attendance. Secondary outcome measures included use of ancillary medications, number of side effects reported and withdrawal and craving ratings. FINDINGS: A total of 59 of the 77 (77%) in-patients assigned to the bup-nx condition achieved the treatment success criterion compared to eight of the 36 (22%) assigned to clonidine, whereas 46 of the 157 (29%) out-patients assigned to the bup-nx condition achieved the treatment success criterion, compared to four of the 74 (5%) assigned to clonidine. CONCLUSION: The benefits of bup-nx for opioid detoxification are supported and illustrate important ways in which clinical research can be conducted in community treatment programs.