ISSN:0003-3022    

出版商:OVID    

年代:2002

数据来源: OVID

ISSN:0003-3022    

出版商:OVID    

年代:2002

数据来源: OVID

ISSN:0003-3022    

出版商:OVID    

年代:2002

数据来源: OVID

ISSN:0003-3022    

出版商:OVID    

年代:2002

数据来源: OVID

摘要:

BackgroundPerioperative myocardial ischemia is conventionally monitored using five electrocardiographic leads, with only one precordial lead placed at V5. This is based on studies from more than a decade ago. The authors reassessed this convention by analyzing data obtained from continuous on-line 12-lead electrocardiographic monitoring.MethodsOne hundred eighty-five consecutive patients undergoing vascular surgery were monitored by continuous 12-lead ST-trend analysis during and for 48–72 h after surgery. Cardiac troponin I was measured in the first 3 postoperative days, and cardiac outcome was prospectively recorded. Ischemia was defined as ST deviation, relative to the reference preanesthesia electrocardiogram, of 0.2 mV or more in one lead or 0.1 mV or more in two contiguous leads, lasting more than 10 min.ResultsDuring 11,132 patient-hours of monitoring, 38 patients (20.5%) had 66 transient ischemic events, with all but one denoted by ST-segment depression. Twelve patients (6.5%) sustained postoperative infarction (cardiac troponin I > 3.1 ng/ml). Among the 38 patients with ischemia, lead V3most frequently (86.8%) demonstrated ischemia, followed by V4(78.9%) and V5(65.8%). Among the 12 patients with infarction, V4was most sensitive to ischemia (83.3%), followed by V3and V5(75% each). Combining two precordial leads increased the sensitivity for detecting ischemia (97.4% for V3+ V5and 92.1% for either V4+ V5or V3+ V4) and infarction (100% for V4+ V5or V3+ V5and 83.3% for V3+ V4). On average, baseline preanesthesia ST was above isoelectric in V1through V3and below isoelectric in V5through V6. Lead V4was closest to the isoelectric level on the baseline electrocardiogram, rendering it most suitable for ischemia monitoring.ConclusionsAs a single lead, V4is more sensitive and appropriate than V5for detecting prolonged postoperative ischemia and infarction. Two precordial leads or more are necessary so as to approach a sensitivity of greater than 95% for detection of perioperative ischemia and infarction.

ISSN:0003-3022    

出版商:OVID    

年代:2002

数据来源: OVID

摘要:

BackgroundThe renin–angiotensin system is involved in blood pressure regulation. The insertion/deletion (I/D) polymorphism of the angiotensin-converting enzyme (ACE) gene is known to be associated with variation of plasma and cellular ACE concentrations. Furthermore, changes in arterial function have been suggested to be associated to theDDgenotype. The aim of the study was to investigate the arterial vascular response to a physiologic stimulus (i.e., flow) according to theI/DACEgene polymorphism.MethodsSixty patients scheduled for coronary artery bypass grafting (n = 24) or valve surgery (n = 36) under normothermic cardiopulmonary bypass were genotyped in a blind manner by polymerase chain reaction. Mean arterial pressure was measured at pump flows ranging from 1 to 3 l · min−1· m−2by 0.25 l · min−1· m−2step each 15 s, to obtain a pressure–flow relation. Independent factors associated with the variation of the slope of the pressure–flow relation curve were assessed by multivariate analysis.ResultsWe found aDallelic frequency of 0.54. Patients were separated in two groups (DD, n = 16;ID/II, n = 44). There were no significant difference with regard to preoperative and intraoperative data between the two groups.DDpatients had their pressure–flow relation curves shifted upward (with higher pressures as flow increased), indicating a lesser decrease in vascular resistance. Furthermore,DDgenotype was the only independent predictor of the slope of the curves (21.5 ± 4.2vs.18.1 ± 5 mmHg/[l · min−1· m−2] forDDandID/II, respectively;P= 0.02; values are mean ±SD).ConclusionThese results show that vasomotor properties are influenced by theI/Dpolymorphism of theACEgene.

ISSN:0003-3022    

出版商:OVID    

年代:2002

数据来源: OVID

摘要:

BackgroundThe efficacy of acute normovolemic hemodilution (ANH) in decreasing allogeneic blood requirements remains controversial during cardiac surgery.MethodsIn a prospective, randomized study, 80 adult cardiac surgical patients with normal cardiac function and no high risk of ischemic complications were subjected either to ANH, from a mean hematocrit of 43% to 28%, or to a control group. Aprotinin and intraoperative blood cell salvage were used in both groups. Blood (autologous or allogeneic) was transfused when the hematocrit was less than 17% during cardiopulmonary bypass, less than 25% after cardiopulmonary bypass, or whenever clinically indicated.ResultsThe amount of whole blood collected during ANH ranged from 10 to 40% of the patients’ estimated blood volume. Intraoperative and postoperative blood losses were not different between control and ANH patients (total blood loss, control: 1,411 ± 570 ml, n = 41; ANH: 1,326 ± 509 ml, n = 36). Allogeneic blood was given in 29% of control patients (median, 2; range, 1–3 units of packed erythrocytes) and in 33% of ANH patients (median, 2; range, 1–5 units of packed erythrocytes;P= 0.219). Preoperative and postoperative platelet count, prothrombin time, and partial thromboplastin time were similar between groups. Perioperative morbidity and mortality were not different in both groups, and similar hematocrit values were observed at hospital discharge (33.7 ± 3.9% in the control group and 32.6 ± 3.7% in the ANH group; nonsignificant)ConclusionsHemodilution is not an effective means to lower the risk of allogeneic blood transfusion in elective cardiac surgical patients with normal cardiac function and in the absence of high risk for coronary ischemia, provided standard intraoperative cell saving and high-dose aprotinin are used.

ISSN:0003-3022    

出版商:OVID    

年代:2002

数据来源: OVID

摘要:

BackgroundNeonates with functional single ventricle often require hypoxic or hypercapnic inspired gas mixtures to reduce pulmonary overcirculation and improve systemic perfusion. Although the impact of these treatments on arterial oxygen saturation has been described, the effects on cerebral oxygenation remain uncertain. This study examined the effect of these treatments on cerebral oxygen saturation and systemic hemodynamics.MethodsNeonates with single ventricle mechanically ventilated with room air were enrolled in a randomized crossover trial of 17% inspired oxygen or 3% inspired carbon dioxide. Each treatment lasted 10 min, followed by a 10–20-min washout period. Cerebral and arterial oxygen saturation were measured by cerebral and pulse oximetry, respectively. Cerebral oxygen saturation, arterial oxygen saturation, and other physiologic data were continuously recorded.ResultsThree percent inspired carbon dioxide increased cerebral oxygen saturation (56 ± 13 to 68 ± 13%;P< 0.01), whereas 17% inspired oxygen had no effect (53 ± 13 to 53 ± 14%;P= 0.8). Three percent inspired carbon dioxide increased the mean arterial pressure (45 ± 8 to 50 ± 9 mmHg;P< 0.01), whereas 17% inspired oxygen had no effect. And 3% inspired carbon dioxide decreased arterialpH and increased arterial carbon dioxide and oxygen tensions.ConclusionsInspired 3% carbon dioxide improved cerebral oxygenation and mean arterial pressure. Treatment with 17% inspired oxygen had no effect on either.

ISSN:0003-3022    

出版商:OVID    

年代:2002

数据来源: OVID

摘要:

BackgroundThe laryngeal mask airwayProSeal™(PLMA™), a new laryngeal mask device, was compared with the laryngeal mask airwayClassic™(LMA™) with respect to: (1) insertion success rates and times; (2) efficacy of seal; (3) fiberoptically determined anatomic position; (4) orogastric tube insertion success rates and times; (5) total intraoperative complications; and (6) postoperative sore throat in nonparalyzed adult patients undergoing general anesthesia, hypothesizing that these would be different.MethodsThree hundred eighty-four nonparalyzed anesthetized adult patients (American Society of Anesthesiologists physical status I–II) were randomly allocated to thePLMA™orLMA™for airway management. In addition, 50% of patients were randomized for orogastric tube placement. Unblinded observers collected intraoperative data, and blinded observers collected postoperative data.ResultsFirst-attempt insertion success rates (91vs.82%,P= 0.015) were higher for theLMA™, but after three attempts success rates were similar (LMA™, 100%;PLMA™, 98%). Less time was required to achieve an effective airway with theLMA™(31 ± 30vs.41 ± 49 s;P= 0.02). ThePLMA™formed a more effective seal (27 ± 7vs.22 ± 6 cm H2O;P< 0.0001). Fiberoptically determined anatomic position was better with theLMA™(P< 0.0001). Orogastric tube insertion was more successful after two attempts (88vs.55%;P< 0.0001) and quicker (22 ± 18vs.38 ± 56 s) with thePLMA™. During maintenance, thePLMA™failed twice (leak, stridor) and theLMA™failed once (laryngospasm). Total intraoperative complications were similar for both groups. The incidence of postoperative sore throat was similar.ConclusionIn anesthetized, nonparalyzed patients, theLMA™is easier and quicker to insert, but thePLMA™forms a better seal and facilitates easier and quicker orogastric tube placement. The incidence of total intraoperative complications and postoperative sore throat are similar.

ISSN:0003-3022    

出版商:OVID    

年代:2002

数据来源: OVID

摘要:

BackgroundThe authors determined the efficacy of using the intubating laryngeal mask airwayFastrachTM(ILMTM) as a ventilatory device and aid to flexible lightwand–guided tracheal intubation in patients with unpredicted failed laryngoscope-guided tracheal intubation when managed by experienced anesthetists.MethodsDuring a 27-month period, 16 experienced anesthetists agreed to use theILMTMas an airway device and airway intubator in patients (aged > 18 yr) with predicted normal airways who were subsequently found to be difficult to intubate (three failed attempts at laryngoscopy). IntubationviatheILMTMwas performed with a flexible lightwand. The number of attempts atILMTMplacement, the number of adjusting maneuvers, the number of attempts at tracheal intubationviatheILMTM,and any episodes of hypoxia (oxygen saturation < 90%) were recorded.ResultsForty-four of 11,621 patients (0.4%) met the inclusion criteria.ILMTMinsertion and ventilation was successful at the first attempt in 40 of 44 patients (91%) and at the second attempt in 4 of 44 (9%). Flexible lightwand–guided tracheal intubationviatheILMTMwas successful in 38 of 44 patients (86%) at the first attempt, 3 of 44 (7%) at the second attempt, 2 of 44 (5%) at the third to fifth attempts, and failed in 1 of 44 (2%). The median number of adjusting maneuvers before successful intubation was 1 (range, 0–4). Hypoxia occurred in 5 patients beforeILMTMinsertion (range, 52–82%), but none afterILMTMinsertion. No patient developed hypoxia during or after intubationviatheILMTM.ConclusionTheILMTMis an effective ventilatory device and aid to flexible lightwand–guided tracheal intubation in adult patients with predicted normal airways in whom laryngoscope-guided tracheal intubation subsequently fails when managed by experienced anesthetists.

ISSN:0003-3022    

出版商:OVID    

年代:2002

数据来源: OVID