ISSN:0003-3022    

出版商:OVID    

年代:2000

数据来源: OVID

ISSN:0003-3022    

出版商:OVID    

年代:2000

数据来源: OVID

ISSN:0003-3022    

出版商:OVID    

年代:2000

数据来源: OVID

ISSN:0003-3022    

出版商:OVID    

年代:2000

数据来源: OVID

摘要:

BackgroundObstacles to the use of patient-controlled analgesia (PCA) by elderly surgical patients have not been well-documented. Age differences in preoperative psychological factors, postoperative pain and analgesic consumption, treatment satisfaction, and concerns regarding PCA were measured to identify factors important to effective PCA use.MethodsPreoperatively, young (mean age ± SD, 39 ± 9 yr; n = 45) and older (mean age ± SD, 67 ± 8 yr; n = 44) general surgery patients completed measures of attitudes toward and expectations of postoperative pain and PCA, psychological distress, health opinions, self-efficacy, and optimism. On the first 2 postoperative days, pain at rest and with movement and satisfaction with pain control were assessed using visual analog scales. Daily opioid intake was recorded. When PCA was discontinued, satisfaction and concerns about it were assessed.ResultsThe older patients expected less intense pain (P≤ 0.003) and preferred less information about (P≤ 0.02) and involvement in (P≤ 0.002) health care than young patients. There were no age differences with regard to pain at rest (P≤ 0.22) or with movement (P≤ 0.68). The older group self-administered less opioid than the young group (P≤ 0.0001) and received PCA for more days than the young group (P≤ 0.004). The groups did not differ in concerns about pain relief, adverse drug effects, including opioid addiction, and equipment use or malfunction. Satisfaction with PCA was high and did not differ between the groups.ConclusionsPatient-controlled analgesia use was not hindered by age differences in beliefs about postoperative pain and opioids. Younger and older patients attained comparable levels of analgesia and were equally satisfied with their pain control.

ISSN:0003-3022    

出版商:OVID    

年代:2000

数据来源: OVID

摘要:

BackgroundCerebral hyperthermia after hypothermic cardiopulmonary bypass has been poorly documented for adults and never in children. This study was designed to monitor brain temperature during and up to 6 h after cardiopulmonary bypass in infants and children.MethodsFifteen infants and children, between 3 months and 6 yr of age, were studied. A right retrograde jugular bulb catheter was used to measure the jugular venous bulb temperature (JVBT) during the procedure and the first 6 h in the critical care unit. The temperature of the blood from the bypass machine was measured at the aorta through the cannula using an indwelling temperature probe. All data were acquired every minute.ResultsThe age of the patients ranged from 3 to 71 months (median, 15 months). The mean weight was 11.5 ± 8.4 kg. The mean JVBT recorded at the end of cardiopulmonary bypass was 36.9 ± 1.4°C but reached 39.6 ± 0.8°C after six h (P< 0.01). The kinetics of brain rewarming was determined by the slope of the mean JVBT and corresponded to y ± 0.006× + 37.21 (r2= 0.97). The JVBT differed from the tympanic temperature after 200 min (P< 0.01) and the lower esophageal (P< 0.05) and rectal (P< 0.001) temperatures after 300 min. After 6 h, the tympanic, rectal, and lower esophageal temperatures were 37.8 ± 0.9, 37.7 ± 0.6, and 38.4 ± 0.7°C, respectively, whereas the JVBT was 39.6 ± 0.8°C (P< 0.001). However, the correlation coefficients between the JVBT and the tympanic, rectal, and esophageal temperatures were 0.98, 0.85, and 0.97, respectively. No complications were recorded with placement of the jugular bulb catheter.ConclusionsMean JVBT was significantly increased over the mean core temperature at all times from rewarming by cardiopulmonary bypass onward. Although the lower esophageal, rectal, and tympanic temperatures correlated well with JVBT, all three failed to reflect JVBT during recovery. This observation might help to elucidate factors involved in the functional and structural neurologic injury known to occur in pediatric patients.

ISSN:0003-3022    

出版商:OVID    

年代:2000

数据来源: OVID

摘要:

BackgroundA new pulmonary drug delivery system produces aerosols from disposable packets of medication. This study compared the pharmacokinetics and pharmacodynamics of morphine delivered by an AERx prototype with intravenous morphine.MethodsFifteen healthy volunteers were enrolled. Two subjects were administered four inhalations of 2.2 mg morphine each at 1-min intervals or 4.4 mg over 3 min by intravenous infusion. Thirteen subjects were given twice the above doses,i.e., eight inhalations or 8.8 mg intravenously over 7 min. Arterial blood sampling was performed every minute during administration and at 2, 5, 7, 10, 15, 20, 45, 60, 90, 120, 150, 180, and 240 min after administration. The effect of morphine was assessed by measuring pupil diameter and ventilatory response to a hypercapnic challenge. Pharmacokinetic and pharmacodynamic analyses were performed simultaneously using mixed-effect models.ResultsThe pharmacokinetic data after intravenous administration were described by a three-exponent decay model preceded by a lag time. The pharmacokinetic model for administration by inhalation consisted of the three-exponent intravenous pharmacokinetic model preceded by a two-exponent absorption model. The authors found that, with administration by inhalation, the total bioavailability was 59%, of which 43% was absorbed almost instantaneously and 57% was absorbed with a half-life of 18 min. The median times to the half-maximal miotic effects of morphine were 10 and 5.5 min after inhalation and intravenous administration, respectively (P< 0.01). The pharmacodynamic parameter ke0was approximately 0.003 min−1.ConclusionsThe onset and duration of the effects of morphine are similar after intravenous administration or inhalationviathis new pulmonary drug delivery system. Morphine bioavailability after such administration is 59% of the dose loaded into the dosage form.

ISSN:0003-3022    

出版商:OVID    

年代:2000

数据来源: OVID

摘要:

BackgroundCentral venous infusion of cold fluid may be a useful method of inducing therapeutic hypothermia. The aim of this study was to quantify systemic heat balance and regional distribution of body heat during and after central infusion of cold fluid.MethodsThe authors studied nine volunteers, each on two separate days. Anesthesia was maintained with use of isoflurane, and on each day 40 ml/kg saline was infused centrally over 30 min. On one day, the fluid was 20°C and on the other it was 4°C. By use of a tympanic membrane probe core (trunk and head) temperature and heat content were evaluated. Peripheral compartment (arm and leg) temperature and heat content were estimated with use of fourth-order regressions and integration over volume from 18 intramuscular thermocouples, nine skin temperatures, and “deep” hand and foot temperature. Oxygen consumption and cutaneous heat flux estimated systemic heat balance.ResultsAfter 30-min infusion of 4°C or 20°C fluid, core temperature decreased 2.5 ± 0.4°C and 1.4 ± 0.2°C, respectively. This reduction in core temperature was 0.8°C and 0.4°C more than would be expected if the change in body heat content were distributed in proportion to body mass. Reduced core temperature resulted from three factors: (1) 10–20% because cutaneous heat loss exceeded metabolic heat production; (2) 50–55% from the systemic effects of the cold fluidper se; and (3) approximately 30% because the reduction in core heat content remained partially constrained to core tissues. The postinfusion period was associated with a rapid and spontaneous recovery of core temperature. This increase in core temperature was not associated with a peripheral-to-core redistribution of body heat because core temperature remained warmer than peripheral tissues even at the end of the infusion. Instead, it resulted from constraint of metabolic heat to the core thermal compartment.ConclusionsCentral venous infusion of cold fluid decreases core temperature more than would be expected were the reduction in body heat content proportionately distributed. It thus appears to be an effective method of rapidly inducing therapeutic hypothermia. When the infusion is complete, there is a spontaneous partial recovery in core temperature that facilitates rewarming to normothermia.

ISSN:0003-3022    

出版商:OVID    

年代:2000

数据来源: OVID

摘要:

BackgroundVentilator-associated pneumonia is the leading nosocomial infection in critically ill patients. The frequency of ventilator-associated pneumonia caused by multidrug-resistant bacteria has increased in recent years, and these pathogens cause most of the deaths attributable to pneumonia. The authors, therefore, evaluated factors associated with selected multidrug-resistant ventilator-associated pneumonia in critical care patients.MethodsThe authors prospectively recorded potential risk factors at the time of intensive care unit admission. An endotracheal aspirate was obtained in all patients who met clinical criteria for pneumonia. Patients were considered to have ventilator-associated pneumonia only when they met the clinical criteria and aspirate culture was positive for bacteria 48 h or more after initiation of mechanical ventilation. Pediatric patients were excluded. Adult patients with ventilator-associated pneumonia were first grouped as “early-onset” (< 5 days) and “late-onset,” determined by episodes of ventilator-associated pneumonia, and then, assigned to four groups based on the bacteria cultured from their tracheal aspirates:Pseudomonas aeruginosa,Acinetobacter baumanii,methicillin-resistant staphylococci, and all others. The first three bacteria were considered to be multidrug resistant, whereas the others were considered to be antibiotic susceptible. Potential risk factors were evaluated with use of univariate statistics and multivariate regression.ResultsAmong 486 consecutive patients admitted during the study, 260 adults underwent mechanical ventilation for more than 48 h. Eighty-one patients (31%) experienced 99 episodes of ventilator-associated pneumonia, includingPseudomonas(33 episodes), methicillin-resistant staphylococci (17 episodes),Acinetobacter(9 episodes), and nonresistant bacteria (40 episodes). Sixty-six of these episodes were early onset and 33 episodes were late onset. Logistic regression analysis identified three factors significantly associated with early-onset ventilator-associated pneumonia caused by any one of the multidrug-resistant bacterial strains: emergency intubation (odds ratio, 6.4; 95% confidence interval, 2.0–20.2), aspiration (odds ratio, 12.7; 95% confidence interval, 2.4–64.6), and Glasgow coma score of 9 or less (odds ratio, 3.9; 95% confidence interval, 1.3–11.3).A.baumanii–related pneumonia cases were found to be significantly associated with two of these factors: aspiration (odds ratio, 14.2; 95% confidence interval, 1.5–133.8) and Glasgow coma score (odds ratio, 6.0; 95% confidence interval, 1.1–32.6).ConclusionsThe authors recommend that patients undergoing emergency intubation or aspiration or who have a Glasgow coma score of 9 or less be monitored especially closely for early-onset multidrug-resistant pneumonia. The occurrence of aspiration and a Glasgow coma score of 9 or less are especially associated with pneumonia caused byA.baumanii.

ISSN:0003-3022    

出版商:OVID    

年代:2000

数据来源: OVID

摘要:

BackgroundContracting muscle emits sounds. The purpose of this study was to compare the time course of muscular paralysis at the adductor pollicis muscle (AP) with use of acoustic myography and mechanomyography.MethodsThirteen elective surgery patients, American Society of Anesthesiologists physical status I, received rocuronium (0.6 mg/kg intravenously) as a bolus dose during general anesthesia. Force of AP was measured with use of a strain gauge, and sounds were recorded simultaneously with use of a small condenser microphone fixed on the palmar surface of the hand over the AP. Supramaximal stimulation was applied to the ulnar nerve at 0.1 Hz for 45–60 min. In seven patients, the response to train-of-four stimulation was also recorded during recovery.ResultsForce and sounds both were equally sensitive in measuring maximum block. The relation between sound and force was curvilinear, with good agreement near 0 and 100% and acoustic response exceeding mechanical response at intermediate levels of block. The acoustic signal had a slower onset and a faster recovery than the force response. The fade response of sound to train-of-four stimulation also recovered faster than that of force.ConclusionAcoustic myography is an alternative method to monitor muscular paralysis that is easy to set up and applicable to most superficial muscles. However, the time course of relaxation at AP using acoustic myography differs from the time course of force relaxation. Therefore, these two methods are not equivalent when applied to AP.

ISSN:0003-3022    

出版商:OVID    

年代:2000

数据来源: OVID