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J Kraidin

Publications and source records attributed to J Kraidin.

4 recordsLinked to original sources

Predictors of pulse oximetry data failure.

BACKGROUND: Pulse oximeters have been reported to fail to record data in 1.12-2.50% of cases in which anesthesia records were handwritten. There is reason to believe that these may be underestimates. Computerized anesthesia records may provide insight into the true incidence of pulse oximetry data failures and factors that are associated with such failures. METHODS: The current study reviewed case files of 9,203 computerized anesthesia records. Pulse oximetry data failure was defined as the presence of at least one continuous gap in data > or = 10 min in duration in a case. A multivariate logistic regression model was used to identify predictors of pulse oximetry data failure, and a modified case-control method was used to determine whether extremes of blood pressure and hypothermia during the procedure were associated with pulse oximetry data failure. RESULTS: The overall incidence of cases that had at least one continuous gap of > or = 10 min in pulse oximetry data was 9.18%. The independent preoperative predictors of pulse oximetry data failure were ASA physical status 3,4, or 5 and orthopedic, vascular, and cardiac surgery. Intraoperative hypothermia, hypotension, hypertension, and duration of procedure were also independent risk factors for pulse oximetry data failure. CONCLUSIONS: Pulse oximetry data failure rates based on review of computerized records were markedly greater than those previously reported. Physical status, type of surgery, and intraoperative variables were risk factors for pulse oximetry data failure. Regulations and expectations regarding pulse oximetry monitoring should reflect the limitations of the technology.

Humans↗

Continuous noninvasive cardiac output as estimated from the pulse contour curve.

We developed a noninvasive computer-based system for estimating continuous cardiac output by a modified pulse contour method using a finger pressure waveform. The method requires no individual patient calibration or baseline cardiac output. First, we calibrated the system in a "learn" group of 20 patients. The computer-based cardiac output was then compared with thermodilution cardiac output in 27 patients undergoing coronary artery bypass surgery. A total of 94 cardiac outputs were performed (three averaged per determination) at four predetermined time periods: preinduction, postinduction, prebypass, and postbypass. During determination of each thermodilution cardiac output, the pulse wave data were simultaneously recorded on cassette tape. The patients had cardiac outputs ranging from 2.9 to 6.4 L/min. The correlation coefficient was 0.75. The average thermodilution cardiac output was 4.50 (+/- 0.83 SD) L/min, while the cardiac output derived from the finger pressure wave was 4.48 (+/- 0.7 SD) L/min (95% confidence interval [CI] of difference, 0-3.2%). The mean difference between the two methods was 0.02 (+/- 0.55 SD) L/min. The 95% CI for the bias was 0.0001 to 0.036 L/min. The 95% CI for the lower limit of agreement was -1.12 to -1.06 L/min; the upper limit for the 95% CI was 1.09 to 1.16 L/min. The program demonstrated that information about cardiac output can be obtained by using the Finapres device (Ohmeda, Boulder, CO). The cardiac output values obtained by this continuous noninvasive technique were within +/- 20% of the simultaneous thermodilution values 87% of the time. This was true over the narrow range of cardiac outputs (2.9 to 6.4 L/min) and wide range of heart rates (45 to 140 beats/min).

Adult↗