摘要:

We tested prospectively 30 hypotensive shock patients using a continuous, on-line, real-time hemodynamic and oxygen transport monitoring system with a previously described predictive index, modified for the clinical conditions in our ICU. Continuous monitoring and display of cardiac output and 20 or more derived variables, together with the predictive index, were a feasible and useful approach. Unlike previously documented series of elective postoperative general surgical patients, our series consisted of patients with multiple trauma, myocardial infarction, sepsis, and other medical emergencies as well as postoperative cardiac and general surgical patients, all of whom had respiratory failure (acute respiratory distress syndrome). In addition to these differences, our patients were invariably admitted to the ICU after the nadir of their hypotensive crisis. To compare the continuous recorded values with previous studies that used intermittent measurements, three comparable time intervals were selected; data at these time intervals and the predictions derived from them were in satisfactory agreement with prior studies. Moreover, therapeutic goals based on the median values of survivors of the present series were similar, but not identical, to prior series despite differences in the clinical mix and the later postresuscitation ICU admissions of our series.

ISSN:0090-3493    

出版商:OVID    

年代:1987

数据来源: OVID

摘要:

Because of large stores of CO2in different body tissues, metabolic change cannot be detected by measuring gas exchange until the CO2stores have adapted to the new situation. Similarly, changes in the CO2stores not due to metabolic alterations, may lead to error in gas exchange measurements.We studied CO2production (Vco2) and oxygen consumption (Vo2) in mechanically ventilated ICU patients, where CO2stores were altered by: a) changing minute ventilation by 15%, b) reducing body temperature, and c) changing the level of sedation. Expired gases went through a mixing chamber and were analyzed continuously by a mass spectrometer. Signals from this instrument, together with gas-volume signals from the ventilator, were fed to a computer for calculation of Vo2and Vco2. Twenty to 120 min were required to reach a stable level, depending on the patient's size and circulatory response. Similar results were obtained by computer simulation using a five- compartment model of CO2stores.These experiments indicate that measuring Vo2(for calculation of metabolic respiratory quotient [RQ]) in ventilated patients should occur after the patients maintain a 60-min period of stable body temperature and awareness. Ventilatory variables should not be changed substantially during the 90-min period before gas sampling. Cardiac output and muscle blood flow should not have changed 2 to 3 h before measuring RQ. If muscle blood flow is low, the stable periods for body temperature and ventilatory variables should be increased.

ISSN:0090-3493    

出版商:OVID    

年代:1987

数据来源: OVID

摘要:

A prospective randomized study to compare two physiologic end-points for titrating positive end-expiratory pressure (PEEP) was performed in patients with early, moderate arterial hypoxemia after surgery or trauma. All patients initially received 5 cm H2O of PEEP. In group 1 patients, PEEP was increased only if Pao2decreased below 65 torr on an inspired oxygen fraction (FIO2) of 0.45. PEEP was then added in 2− to 3-cm H2O increments until Pao2again was above 65 torr. Group 2 patients were treated with incremental PEEP until the Pao2/Fio2ratio was greater than 300 or physiologic shunt (Qsp/Qt) was less than 0.20. All therapy other than PEEP was similar in the two groups.There were no statistically significant differences in entry Pao2(mean 85 ± 11 [SD] and 87 ± 11 torr in groups 1 and 2, respectively), and Qsp/Qt was 0.22 in each group. Five (28%) of 18 patients in group 1 and 19 (95%) of 20 patients in group 2 received more than 5 cm H2O of PEEP. Between groups 1 and 2 there were no statistically significant differences in days intubated (3.4 ± 3 vs. 5.3 ± 5, respectively), ICU days (5.3 ± 3 vs. 6.6 ± 5), hospitalization days (26 ± 24 vs. 28 ± 24), incidence of pulmonary barotrauma (0/18 vs. 1/20), ICU mortality (22% vs. 20%), or overall mortality (33% vs. 25%). The number of blood gas analyses and cardiac output measurements, and the total hospital charges were also similar in both groups.Thus, titrating PEEP therapy to a prescribed Qsp/ Qt of less than 0.20 did not improve patient outcome or decrease resource utilization. Instead, group 2 patients were subjected to more frequent manipulation of PEEP levels than group 1 patients, who received PEEP therapy titrated to saturate hemoglobin at a nontoxic Fio2.

ISSN:0090-3493    

出版商:OVID    

年代:1987

数据来源: OVID

摘要:

We used metoprolol orally or iv in 25 patients with multifocal atrial tachycardia that was complicating severe cardiopulmonary illness, and we observed its effect on heart rate and rhythm, BP, and arterial blood gases. All patients showed a dramatic slowing of heart rate, averaging 54.0 ± 4.0 beat/min (p< .001), with only small and transient fall in BP. Seventeen (68%) patients experienced conversion to sinus rhythm, 11 immediately, and six more within 3 h. Time to response averaged 5.1 h with the oral form but was less than 10 min when the drug was given iv. The mean oral dose required was 32.5 mg, and the mean iv dose was 6.5 mg. No patient experienced clinically apparent hemodynamic or respiratory deterioration as a result of metoprolol administration. While arterial pH and Paco2were unaltered by metoprolol, mean Pao2increased by 12.2 ± 5.8 torr (p< .05), the increase being greatest in patients with more severe gas-exchange derangement. We conclude that metoprolol is effective in the management of multifocal atrial tachycardia.

ISSN:0090-3493    

出版商:OVID    

年代:1987

数据来源: OVID

摘要:

We analyzed the relationship of increases in oxygen delivery to changes in oxygen consumption in ten patients with hyperdynamic septic shock. Increases in oxygen delivery from 413 ± 14 (SEM) to 535 ± 19 ml/min-m2(p< .01) were associated with increases in oxygen consumption from 136 ± 10 to 161 ± 5 ml/min-m2(p< .05). Arterial lactate decreased from 4.6 ± 1.6 to 2.1 ± 0.3 mmol/L (p< .05). These observations suggest that oxygen utilization is perfusion-limited in hyperdynamic septic shock.

ISSN:0090-3493    

出版商:OVID    

年代:1987

数据来源: OVID

摘要:

Specimen cultures were evaluated in 49 catheterized patients who had a known focus of infection (primarily intra-abdominal peritonitis). Bacteria were recovered from 2% of flush solutions, 14% of transducer domes, 18% of diaphragms, and 24% of cardiac output fluids; however, these bacteria were not found in cultures of the pulmonary artery (PA) catheter segments. The rates of positive PA catheter-aspirate cultures were 30.6% on day 1, 20.4% on day 2, and 32.7% on day 3 (not statistically different). PA catheter-aspirate cultures had a sensitivity of 5.7% and a positive predictive value of 30% for catheter-related infection, and 15% sensitivity and 40% positive predictive value for peripheral bacteremia. While 95% (55 of 58) of the catheter- aspirate cultures were false-positives, only 0.5% (3 of 588) were true-positives. Peripheral blood cultures were positive in 10% of the patients, but the catheter segments were sterile or grew different organisms. Arterial line cultures had zero sensitivity and predictive value to detect catheter-related infection, and 15% sensitivity and 40% predictive value to detect peripheral bacteremia.Thus, PA catheter-aspirate cultures, routine peripheral blood cultures, and arterial cultures cannot be recommended to detect PA catheter-related infection. Catheter-related infection confirmed by catheter-segment cultures was 10.2% when the PA catheters were removed after 73 ± 6.5 (SD) h. Bacteria from catheter- segment cultures corresponded to those from the primary infection site.

ISSN:0090-3493    

出版商:OVID    

年代:1987

数据来源: OVID

摘要:

We compared complications of pulmonary artery catheter (PAC) insertion and maintenance at internal jugular (IJ) vs. subclavian (SC) sites. Patients were randomized into groups using an IJ or SC route, and insertions were timed. An air-permeable dressing and anticontamination shield were used.Catheters were removed 72 h after insertion. If PAC monitoring was still needed, a new catheter was either inserted over a guidewire at the initial insertion site or inserted at a new site. On removal, the catheter tip, introducer-sheath tip, and catheter within the shield were submitted for semiquantitative culture.Sixty-six catheters were initially inserted, and 26 were changed. No determinative differences in the time for venous cannulation were found, but the IJ route was slightly faster. In 3% of the catheterizations, serious complications arose. The infection rate was 2% for initial catheters, 8% for second catheters placed over a guidewire, and 15% for second catheters placed at a new site. These differences were not consequential. No local infection or catheter-related sepsis occurred.Thus, using a standard, sterile-insertion technique and a catheter-maintenance protocol yielded a low risk of insertion and infectious complications at either the IJ or SC site. Our data indicated that PACs can be changed safely over a guidewire at 72 h, avoiding further insertion risks without increasing infectious complications.

ISSN:0090-3493    

出版商:OVID    

年代:1987

数据来源: OVID

摘要:

Oxygen delivery (Do2) in patients with acute respiratory failure has been correlated with total lung and chest wall compliance (CT), the optimal positive end- expiratory pressure (PEEP) level reportedly corresponds to maximal Do2. To test the validity of the relationship, we studied the correlation between CT and Do2in 12 septic pigs with acute respiratory failure induced by continuous infusion of livePseudomonas aeruginosabacteria. Cardiac output, pulmonary and systemic arterial BP, blood gases, extravascular lung water, tidal volume, and airway pressure were measured serially in six control animals and six animals receiving increasing amounts of PEEP. There was no significant correlation between Do2and CT in either group; however, animals receiving PEEP had less extravascular lung water.

ISSN:0090-3493    

出版商:OVID    

年代:1987

数据来源: OVID

摘要:

Disturbingly low survival rates after CPR prompted us to carry out a series of studies. Of 272 patients receiving CPR at our 600-bed community hospital in 1984,102 (37.5%) patients survived initial resuscitation and 30 (11%) survived their hospitalization. Of the 102 initial survivors, only 15 patients had received full CPR including cardiac compression and/or defibrillation, endotracheal intubation, and cardiotonic drugs. These data were compared with those for 129 patients admitted to our critical care units in 1982 and 1983 in whom CPR was withheld. These patients had been designated “No CPR” primarily because of their poor response to therapy. There was an 11% survival rate for patients who had received CPR compared to a 16% survival rate for the “No CPR” group. These data suggest that criteria for administering CPR to hospitalized patients should be improved.

ISSN:0090-3493    

出版商:OVID    

年代:1987

数据来源: OVID

摘要:

Management of postoperative diabetes insipidus (DI) frequently requires intermittent treatment with multiple subcutaneous injections of pituitrin or vasopressin, in doses averaging 20 IU/24 h. Use of a syringe pump for a continuous infusion of ultralow doses of pituitrin produced uniform, constant, and sustained reduction of urinary output, thus facilitating regular fluid replacement. Twelve patients with postoperative DI received iv pituitrin at a dose of 1.6 ± 0.26 mIU/kg·h (1 to 2 IU/24 h). The antidiuretic effect began at the third hour of treatment, peaked by the sixth hour (diuresis of 37 ml/h, specific gravity of 1.018 ± 0.002), and was sustained throughout infusion. Polyuria recurred 3 h after the infusion was discontinued; this rapid reversibility is highly advantageous when excessive fluid intake causes overhydration. Pressor effects were not observed during the treatment period.

ISSN:0090-3493    

出版商:OVID    

年代:1987

数据来源: OVID