摘要:

In vitro exposure of normal ORh−PMN to plasma obtained from patients with septic shock results in inhibition of formyl-methionyl-leucyl-phenylalanine stimulated superoxide anion (O2−) production by 40%. Although all reaction velocities and extent of reaction at 5 min were suppressed, neither lag time preceding O2−production nor duration of initial velocity linearity was affected. No such inhibition was noted when plasma from healthy controls or nonseptic critically ill patients was utilized in the reaction. These results demonstrate that neutrophils are not only a cause, but also a target of the septic shock host inflammatory response. (Crit Care Med 1989; 17:1241)

ISSN:0090-3493    

出版商:OVID    

年代:1989

数据来源: OVID

摘要:

Phagocytosis is a major mechanism of defense against bacterial infections. The ingestion of different microorganisms by blood granulocytes or monocytes may involve a variety of cell membrane recognition structures (e.g., immunoglobulin or complement receptors, lectin-like structures or other nonspecific binding sites). It is of interest to know which mechanism plays a prominent role in the management of a particular type of infection.Forty-three pathogenic bacterial suspensions were obtained from patients under mechanical ventilation at the onset of nosocomial lower respiratory tract infections. They were coincubated with blood granulocytes from the same or other patients in the presence or absence of the corresponding serum. Phagocytosis and the oxidative burst were then assayed. We conclude the following: a) Substantial phagocytosis was found under serum-free conditions and the patients' sera did not dramatically enhance bacterial uptake during the first days after the onset of clinical symptoms, b) The phagocytes from an infected patient did not display any peculiar inability to bind to the bacteria that grew successfully in this subject. Hence, the occurrence of a particular infection might be dependent on a defect of intracellular killing of ingested pathogens or on the conditions of infection development.

ISSN:0090-3493    

出版商:OVID    

年代:1989

数据来源: OVID

摘要:

Atropine is used both to treat a variety of clinical disorders and as an antidote to cholinesterase poisoning. While various conditions affect the physiologic responses to atropine, little is known of the pharmacokinetics of this drug except under resting conditions. Pharmacokinetic studies were performed in mongrel dogs under two experimental conditions, moderate hemorrhage and hypothyroidism, to determine whether im absorption and elimination of atropine (0.05 mg/kg body weight) were affected by changes in hemodynamic or metabolic status. Using a randomized, crossover experimental design, it was found that during hypovolemia the mean volume of distribution was reduced by 22% (2.50 ± 0.62 vs. 3.21 ± 0.63 L/kg), with no changes in peak serum level, total atropine availability, elimination half-life, or whole-body clearance. Hypothyroidism was associated with a significant increase in peak serum atropine concentration (26.4 ± 3.9 vs. 20.6 ± 4.9 ng/ml) and drug bioavailability (48.5 ± 8.8 vs. 30.0 ± 10.7 ng/ml-h), while the clearance was reduced by 39% (426 ± 34 vs. 696 ± 187 ng/ml-min). These results suggest that atropine kinetics are not altered appreciably during moderate hemorrhage. In hypothyroidism, alterations in atropine pharmacokinetics may warrant modification of drug dose and frequency of administration.

ISSN:0090-3493    

出版商:OVID    

年代:1989

数据来源: OVID

摘要:

Cardiac arrest has a poor prognosis, regardless of age group. Children who fail to respond to two standard doses of epinephrine (0.01 mg/kg) rarely survive to hospital discharge, and most die without the return of spontaneous circulation (ROSC). We treated seven consecutive children in cardiac arrest with high dose epinephrine (0.2 mg/kg) after failure to respond to two standard doses. Six had prompt and sustained ROSC. By comparison, in the previous 20 consecutive pediatric patients with cardiac arrest in which there was no response to two standard doses of epinephrine, none had ROSC. Previous animal data as well as anecdotal human experience suggest that the standard epinephrine dose (0.01 mg/kg) may be much too low. (Crit Care Med 1989; 17:1258)

ISSN:0090-3493    

出版商:OVID    

年代:1989

数据来源: OVID

摘要:

Nine hundred ninety-four patients were enrolled in a field trial in which ambulance crews were randomly assigned to use simultaneous compression-ventilation (SC-V) CPR or conventional CPR procedures in the prehospital setting. Survival to hospital admission and to discharge was superior in the conventional CPR group vs. the experimental group (p< .01). In a subset of adult cases whose causes of arrest were nontraumatic, survivor rates still favored the conventional CPR group: 33.5% of 337 vs. 22.5% of 365 (p< .001). In limited cases where cardiac arrest was due to other heart disease, was vascular in origin or secondary to other natural diseases or from hypertensive cardiovascular disease, or when ECG on arrival was an agonal rhythm, survival was better (but not statistically significantly) in the experimental group. There were no statistically significant differences in the Glasgow coma scores between surviving patients in either group at 24 h post-hospital admission or discharge. It is concluded that survival in the SC-V CPR group was lower, likely reflecting a deleterious effect of the experimental technique of resuscitation. Also noted was that 14% of the control patients and 6% of the experimental patients survived with manual CPR alone.

ISSN:0090-3493    

出版商:OVID    

年代:1989

数据来源: OVID

摘要:

The hemodynamic response after an iv loading dose of amiodarone for resistant supraventricular tachyar rhythmias was studied in ten critically ill patients receiving a catecholamine infusion for shock. A loading dose of amiodarone, 3.7 to 5.0 mg/kg. was infused over 2 h while the catecholamine infusion dose requirements were monitored. There was a significant decrease in heart rate (mean 16%,p< .01), and an increase in stroke volume index (mean 29%,p< .01) and left ventricular stroke work index (mean 34%,p< .01). Cardiac index, oxygen availability index, and mean arterial pressure were not changed significantly. The reported adrenoreceptor antagonism of amiodarone did not change catecholamine dose requirements in this study. In nine of ten patients, sinus rhythm was achieved and maintained. The loading dose of amiodarone had no significant acute effect on plasma digoxin concentrations. Despite good arrhythmia control, mortality was high.

ISSN:0090-3493    

出版商:OVID    

年代:1989

数据来源: OVID

摘要:

We described 663 unanticipated monitored circulatory events in 247 high-risk surgical patients by simultaneous invasive and noninvasive hemodynamic and oxygen transport monitoring systems. Unanticipated monitored events were defined as sudden reductions (>20%) in cardiac index (CI), Pao2, Sao2, transcutaneous Po2(Ptco2), and Ptco2/Pao2index, or decreases to the lower limits of satisfactory values, specifically: Pao2<70 torr, Sao2<95%, Ptco2<50 torr, and Ptco2/Pao2<0.6. Essentially, monitored events are the small variations superimposed on the overall physiologic patterns that describe the entire course of critical illnesses. Monitored events are described by their baseline values just before each event, at the nadir of the event, and at the recovery from the event. To simplify presentation of complex changes in many variables, the circulatory changes were evaluated in terms of cardiac, pulmonary, and peripheral perfusion functions.Common patterns of these monitored events and the incidence of these patterns in high-risk surgical patients were described. Before the unanticipated monitored event, there were normal or increased heart, lung, and perfusion functions in about three fourths of the events. At the nadir, cardiac functions decreased in about two thirds, perfusion decreased in over half, and lung function fell in only one quarter of the events. Recovery occurred with increased cardiac function in two thirds, improved perfusion in over half, and increased lung function in less than one fifth of these monitored events. Noninvasive and invasive hemodynamic and oxygen transport variables were measured simultaneously to evaluate compensatory and decompensatory patterns. The data provide an information base for criteria that may be used to develop therapeutic decision rules for noninvasive monitoring systems.

ISSN:0090-3493    

出版商:OVID    

年代:1989

数据来源: OVID

摘要:

The relationships between cell metabolism and both hemodynamics and oxygen transport/utilization (Vo2/Do2) pattern were evaluated intra and postoperatively in eight patients undergoing major valvular heart surgery with the aid of moderately hypothermic cardiopulmonary bypass (CPB). Quadriceps femoris specimens were obtained by the needle biopsy technique for muscle ATP, ADP, AMP, phosphocreatine (PCr), creatine and lactate determination at anesthesia induction, after CPB, as well as in the ICU 18 h after surgery. Moreover, hemodynamic variables, oxygen transport and utilization indices, and plasma lactate were measured at the same intervals and throughout the CPB period.After CPB, muscle ATP and PCr contents were reduced (p< .05) as compared to those of both pre-CPB patients and healthy control subjects; muscle and plasma lactate levels were increased (p< .05). Mean Vo2and Do2values measured during CPB significantly decreased (p< .05), but Vo2reduction was proportionally greater than that of Do2(-62% vs. −41%). No correlation was found between Vo2and Do2at that time, but a significant relationship (p< .05) was found at the end of CPB. A further decrease in muscle ATP and PCr levels was measured in the ICU, as muscle and plasma lactate levels were still elevated. At that time, Vo2and Do2were not significantly different from pre-CPB values, but were significantly (p< .05) correlated with each other.Our investigation suggests that in patients undergoing major valvular heart surgery, the use of a moderately hypothermic low-flux, low-pressure CPB can be associated with a condition of inadequate tissue oxygenation, and that the oxygen deficit persists into the postoperative recovery period, leading to marked alterations of cell oxidative metabolic pathways and to the activation of anaerobic metabolism.

ISSN:0090-3493    

出版商:OVID    

年代:1989

数据来源: OVID

摘要:

Twenty preterm newborn infants were randomized to receive either atropine alone (20 μg/kg) or atropine plus succinylcholine (2 mg/kg) before nasotracheal intubation. Heart rate, BP, transcutaneous Po2, and intracranial pressure were monitored continuously before, during, and after intubation. No infants developed bradycardia or hypoxia. Intracranial hypertension developed during intubation in the infants receiving atropine alone, but was prevented by premedication with succinylcholine and atropine (p< .01). A 41% increase in systemic BP occurred immediately after the administration of succinylcholine (p< .01). BP increased during intubation in both groups, and the overall peak BP was not significantly different between the groups. Intubation was significantly shorter in the infants receiving succinylcholine. Premedication with succinylcholine and atropine will facilitate intubation of neonates, and ameliorate the adverse physiologic consequences of this procedure.

ISSN:0090-3493    

出版商:OVID    

年代:1989

数据来源: OVID

摘要:

Neuromuscular blockade by vecuronium infusion is described in 13 patients requiring ventilation in an ICU for periods of 15 to 68 h. A loading dose of vecuronium (0.1 mg/kg) was given, followed by continuous infusion adjusted to maintain approximately 90% block as assessed by the presence of one response to a Train-of-Four stimulation.The average infusion rate was 0.103 mg/kg-h. The average time to complete recovery of myoneural function, as assessed by an obviously sustained response to tetanic stimulation, after the termination of the vecuronium infusion was 28 min. There were no adverse cardiovascular or toxic effects noted as a result of vecuronium administration. Vecuronium administered by infusion produced satisfactory neuromuscular relaxation in patients requiring ventilation in the ICU.

ISSN:0090-3493    

出版商:OVID    

年代:1989

数据来源: OVID