Archive for the ‘Mechanical Ventilation’ Category

Alteration of Pulmonary Oxygenation by Pulmonary Artery Occluded Pressure Measurements in Mechanically Ventilated Patients: Conclusion

Patients with coronary artery disease or with valvular heart disease seem to be candidates for the Pa02 decrease when their resting PAP was elevated, as demonstrated in Figure 3. Both inhalational and opiate anesthetic agents also affect pulmonary oxygenation and vasoreactivity, which seem to be dependent on the existing level of vascular tone. On the other hand, sympathectomy of the pulmonary vasculatures, in this case induced by cervical epidural anesthesia, is unlikely to affect the vasoreactivity to the balloon manipulation. Thus, it remains unclear whether the Pa02 decrease during the balloon inflation was caused by purely mechanical obstruction, and/or by changes in reflex responses due to either anesthetics used or the disease per se. —Āanadianhealthcaremallinc.com
Read the rest of this entry »

Alteration of Pulmonary Oxygenation by Pulmonary Artery Occluded Pressure Measurements in Mechanically Ventilated Patients: Discussion

Alteration of Pulmonary Oxygenation by Pulmonary Artery Occluded Pressure Measurements in Mechanically Ventilated Patients: DiscussionIn the present study, we found that only seven of 101 patients (6.9 percent) developed more than a 100 mm Hg decrease in PaOg/FIOa during the inflation of PAC balloon; the majority of patients showed a relatively small decrease or increase in Pa02. Neither the decrease in PetC02 nor baseline PAP was correlated with the decrease in Pa02 during PAOP measurements. The maximum decrease in PaOa/FIo2 induced by the balloon inflation was 186 mm Hg in the present series of patients. Such a degree of decrease in Pa02 must be crucial and large enough to deteriorate oxygen delivery to the tissues if it occurs in patients with cardiopulmonary instability or acute respiratory failure, even though CO remained unaffected during PAOP measurements. Read the rest of this entry »

Alteration of Pulmonary Oxygenation by Pulmonary Artery Occluded Pressure Measurements in Mechanically Ventilated Patients: Results

Inflation of the PAC balloon caused a slight but statistically significant reduction in PetC02 (0 to 15 mm Hg, Table 1), but no significant differences in any variable of pulmonary and systemic hemodynamics (Table 2). However, there was a significant decrease (more than 50 mm Hg) in PaOa/FIOg in 15 patients (14.9 percent); seven of these patients (6.9 percent) showed a more remarkable decrease (more than 100 mm Hg) in PaOj/FIOg during PAOP measurement (Fig 1). On the other hand, 11 out of 101 patients (10.9 percent) showed a significant increase (more than 50 mm Hg) in PaCVFIo2. There was no significant correlation between changes in PaO/FIOg and those in PetC02 (r = 0.26), nor between changes in PkCV FIo2 and control PAP (r = 0.09, Fig 2). Read the rest of this entry »

Alteration of Pulmonary Oxygenation by Pulmonary Artery Occluded Pressure Measurements in Mechanically Ventilated Patients

Alteration of Pulmonary Oxygenation by Pulmonary Artery Occluded Pressure Measurements in Mechanically Ventilated PatientsThe measurements of PAOP using a flow-directed, balloon-tipped PAC may produce rapid onset of significant hypoxemia either by temporary cessation of mechanical ventilation or by occlusion of a major pulmonary arterial vasculature. The former has been well recognized and thus a simple electronic circuit was constructed for the measurements without separation of the patient from the ventilator. The latter decrease in Pa02 due to inflating the balloon of the PAC per se has recently been reported by us and others. Although the information obtained with inflating the PAC balloon is invaluable and contributes greatly to the management of both critically ill and anesthetized patients, the decrease in Pa02 could cause deterioration of the patients condition in some situations. Therefore, we expanded our study to know its incidence and to examine the types of patients who tend to develop a remarkable decrease in Pa02 during PAOP measurements and whether the changes in Pa02 are related to the existing level of pulmonary vascular tone. Read the rest of this entry »

A Prospective Comparison of IMV and T-Piece Weaning from Mechanical Ventilation: Conclusion

The majority of patients removed from protocol were weaned by IMV with a longer total ventilation time and weaning time. There was a significant difference in TVT between patients in the IMV and T-piece groups who were withdrawn from protocol because two patients (arbitrarily assigned to the IMV group) required longer stabilization, and the number of patients was small. In general, the patients on the medical service required longer mechanical ventilation (stabilization) because of preexisting lung disease and multiorgan system failure. Read the rest of this entry »

A Prospective Comparison of IMV and T-Piece Weaning from Mechanical Ventilation: Discussion

A Prospective Comparison of IMV and T-Piece Weaning from Mechanical Ventilation: DiscussionThis study showed that both medical and surgical patients assigned randomly to either an IMV or T-piece mode could be weaned from mechanical ventilation over the same period. Two-thirds of the patients who were weaned in 2 h were postsurgical patients who were ventilated for <72 h. The majority of these patients had undergone uncomplicated coronary artery bypass grafting (CABG) and usually were weaned as soon as they awoke from anesthesia. This represents a group of patients that usually present minimal problems in weaning from mechanical ventilation rapidly and may represent a bias to the hypothesis. Ideally, the use of a similar protocol with a large group of long-term ventilator patients might uncover differences in success between the two modes of weaning. Read the rest of this entry »

A Prospective Comparison of IMV and T-Piece Weaning from Mechanical Ventilation: Results

Two hundred (200) patients were initially enrolled in the study. The mean age was 53 years (range, 18 to 87) with 134 males and 66 females. Of the 200 patients, 133 were ventilated following surgery or trauma and 67 patients were ventilated for medical diseases (Table 2). There was no difference in age between patients in the IMV and T-piece groups. One hundred sixty-five (165) (82 percent) of the patients were maintained in the study until the weaning phase was initiated, and 155 of the 165 (93 percent) were weaned successfully by protocol. Of the 35 patients withdrawn from the study before the weaning phase was initiated, 20 were ventilated by AMV and 15 by IMV Twenty-four of the 35 (69 percent) patients were withdrawn from protocol because of attending physician preference; four patients were withdrawn because of procedural problems, four because of death, and three because of self-extubation. Twenty-seven of the 35 (77 percent) were surgical patients. In three patients withdrawn due to attending preference, the stabilization mode was changed from AMV to IMV because of respiratory alkalosis. However, in each instance, the change in ventilatory mode did not correct the alkalemia. All surgical patients were weaned on 5 cm HzO PEEP, while all medical patients were weaned on 0 PEEP. Read the rest of this entry »

About

So Many Advances in Medicine, So Many Yet to Come