Patients with Chronic Paralytic/Restrictive Ventilatory Dysfunction (9)
All 37 patients underwent at least one night of Sa02 monitoring on BV assistance with a pulse oximeter with an internal printer (Model 3760, Ohmeda, Louisville, Colo). The 22 patients who were subsequently switched to nocturnal NV-PAP had at least one night of Sa02 monitoring on NV-PAP (Table 2). The overnight mean, low, and worst-hour mean Sa02 and the percentage of time below 90, 85, 80, and 70 percent Sa02 were read directly from the oximeter printout. The value for 4*fedSa0^i wjth rapid recovery from the nadir was counted manually (Fig 1). The inclusion of motion artifacts was minimized by not counting isolated 4%dSa02 episodes accompanied by erratic pulse-rate displays. Sources of interfering signals, such as xenon lamps, fluorescent or infrared lights, and the use of nail polish, were avoided. buy cheap antibiotics
Three patients underwent polysomnography with use of the Vitalog HMS-3000 monitor (Vitalog Monitoring, Redwood City, Calif) both while using BVs and after switching to NV-PAP The system includes continuous monitoring of Sa02, heart rate, body movement and sleep position, nasal air flow, and inductive plethys-mographic recording. The latter two variables denote the decreases in air movement that can result only from the presence of airway obstruction or periods of underventilation.
Table 2—Nocturnal Oxygen Measurements in 22 Patients Switched to NV-PAP
Figure 1. Oxyhemoglobin saturation monitoring of two representative patients. A, Nocturnal Sa02 monitoring demonstrates the prolonged desaturation that occurs in patients with CAH who are underventilated by their BV and who have no sign of obstructive apneas. B, Typical manual tabulation of 4%dSa02 with rapid recovery from nadir.