摘要:

ObjectiveTo determine antioxidant vitamin concentrations, lipid peroxidation, and an index of nitric oxide production in patients in the intensive care unit (ICU) with septic shock and relate the findings to the presence of secondary organ failure.DesignA prospective, observational study.SettingA nine-bed ICU in a University teaching hospital.Patients90 beats/min); e) shock (systolic pressure <90 mm Hg) or receiving inotropes. Fourteen patients also had secondary organ dysfunction.InterventionsNone.Measurements and Main ResultsAntioxidant vitamin concentrations were significantly lower in the patients than the reference range obtained from a comparable group of healthy controls. The mean plasma retinol (vitamin A) concentration was 26.5 +/- 19.3 micro gram/dL compared with 73.5 +/- 18.3 micro gram/dL in healthy subjects (p < .01). Additionally, 13 (81%) patients had retinol values below the lower limit of our reference range (<37.0 micro gram/dL). Tocopherol (vitamin E) plasma concentrations were below the reference range in all patients (<9.0 mg/L), with a mean value of 3.6 +/- 2.0 mg/L compared with 11.5 +/- 1.3 mg/L in healthy subjects (p < .001). Plasma beta carotene and lycopene concentrations were undetectable (<15 micro gram/L) in eight (50%) patients, and below our reference range (<101 micro gram/L and <154 micro gram/L, respectively) in the remaining patients. In the five patients with three or more dysfunctional secondary organs, plasma thiobarbituric acidreactive substances were significantly increased (p < .05), suggesting increased lipid peroxidation. Concentrations of thiobarbituric acidreactive substances correlated negatively with both plasma retinol and plasma tocopherol (r2= .42, p < .01 and r2= .48, p < .005, respectively). In the five patients from whom we were able to collect urine, nitrite excretion was increased approximate 400-fold (p < .001).ConclusionsThese data indicate decreased antioxidant status in the face of enhanced free radical activity, and suggest potential therapeutic strategies involving antioxidant repletion.(Crit Care Med 1995; 23:646-651)

ISSN:0090-3493    

出版商:OVID    

年代:1995

数据来源: OVID

摘要:

ObjectiveTo evaluate the effect of early postoperative feeding with a nutritionally complete enteral diet supplemented with the nutrients arginine, ribonucleic acid (RNA), and omega-3 fatty acids on the immune function in patients undergoing surgery for upper gastrointestinal (GI) malignancies.DesignProspective, randomized, placebo-controlled, double-blind study.SettingSurgical intensive care unit (ICU) in a German university hospital.PatientsForty-two consecutive patients receiving an enteral diet via needle catheter jejunostomy after GI surgery for cancer.InterventionsPatients were randomized to receive either the arginine, RNA, and omega-3 fatty acids supplemented diet or an isocaloric and isonitrogenous placebo diet. Early enteral nutrition was started on postoperative day 1 in the surgical ICU with 20 mL/hr and progressed to the optimal goal of 80 mL/hr by postoperative day 5.Measurements and Main ResultsClinical examination and adverse GI symptoms were recorded on a daily basis. Body weight was determined twice weekly. Immunoglobulin concentrations were determined by laser nephelometry. Interferon-gamma concentrations were measured with a modified enzyme-linked immunosorbent assay method. Fluorescence-activated cell scan flow cytometry was performed to analyze B cells, T lymphocytes and their subsets. Clinical patient characteristics and mean caloric intake were similar between the two groups and both formulas were well tolerated. The number of T lymphocytes and their subsets, helper T cells (CD4) and activated T cells (CD3, HLA-DR), were significantly higher in the supplemented diet group on postoperative days 10 and 16 (p < .05). Mean interferon-gamma concentration after phytohemagglutinin stimulation was higher in the supplemented diet group on postoperative day 16. In the supplemented diet group, mean immunoglobulin M concentrations were significantly higher on postoperative day 10 and mean immunoglobulin G concentrations were higher on postoperative day 16 (p < .05) compared with the results in the placebo group. B-lymphocyte indices were significantly higher in the supplemented vs. the placebo diet group on postoperative days 7 and 10 (p < .05).ConclusionsSupplementation of enteral diet with arginine, RNA, and omega-3 fatty acids in the early postoperative time period improves postoperative immunologic responses and helps to overcome more rapidly the immunologic depression after surgical trauma.(Crit Care Med 1995; 23:652-659)

ISSN:0090-3493    

出版商:OVID    

年代:1995

数据来源: OVID

摘要:

ObjectivesTo determine changes in the absorption of lactulose and mannitol in patients undergoing laparotomy following blunt or penetrating trauma and to correlate any changes in permeability with the severity of injury.DesignNonrandomized study within patient control.PatientsConsecutive patients admitted to the trauma unit following blunt or penetrating trauma with intra-abdominal injuries warranting emergent celiotomy and jejunal access.InterventionsIntestinal permeability was measured in 18 patients within 48 hrs posttrauma by the bolus infusion into the jejunum of nonmetabolized probe molecules, lactulose (molecular weight of 342) and mannitol (molecular weight of 182). Because several patients did not tolerate the bolus infusion, a 3-hr continuous infusion of the probe molecules was used in the last eight patients entered into the study. Intestinal permeability was reassessed before discharge or on days 10 to 12.Measurements and Main ResultsThere was a decrease in urinary lactulose excretion and the lactulose/mannitol ratio between the initial posttrauma measurement and the follow-up permeability measurement using both the bolus infusion (lactulose: initial 0.13 +/- 0.032 vs. follow-up 0.047 +/- 0.012 mmol/6 hrs, p <or=to .05; lactulose/mannitol: initial 0.067 +/- 0.012 vs. follow-up 0.044 +/- 0.012, p = .11) and the continuous infusion (lactulose: initial 0.044 +/- 0.013 vs. follow-up 0.014 +/- 0.002 mmol/2 hrs, p <or=to .05; lactulose/mannitol: initial 0.055 +/- 0.020 vs. follow-up 0.015 +/- 0.007, p <or=to .05). Urine excretion of mannitol was not significantly different between posttrauma and follow-up measurements of intestinal permeability, regardless of the technique used to infuse the lactulose and mannitol. Although the decrease in lactulose and the lactulose/mannitol ratio was significant, only one third of the patients had dramatically increased permeability at the initial measure. Abdominal Trauma Index and Injury Severity Score did not correlate with urinary lactulose excretion or the lactulose/mannitol ratio. Patient tolerance of jejunal administration of lactulose and mannitol was better, using a 3-hr continuous infusion of a dilute solution compared with bolus infusion.ConclusionsIntestinal permeability is increased in the first 48 hrs posttrauma and decreases with recovery. Although one third of the patients had highly increased lactulose/mannitol ratios posttrauma, severity of injury, assessed by common scoring techniques, did not correlate with the degree of permeability. Tolerance to jejunal administration of lactulose and mannitol is improved with a slow infusion of a dilute solution over a 3-hr period compared with bolus administration.(Crit Care Med 1995; 23:660-664)

ISSN:0090-3493    

出版商:OVID    

年代:1995

数据来源: OVID

摘要:

ObjectivesTo study the effects of growth hormone administration on insulin-like growth factor I concentration, nitrogen balance, and fuel utilization, and to study its safety in critically ill nonseptic patients.DesignProspective, randomized, placebocontrolled trial.SettingMedical intensive care unit of a university hospital.PatientsEighteen critically ill nonseptic patients were studied for 8 days after admission.InterventionsGrowth hormone (0.1 mg/kg/day) or placebo was administered as a continuous intravenous infusion on the second, third, and fourth days after admission. The study period was 8 days.Measurements and Main ResultsPlasma hormone concentrations were measured every 6 hrs and average daily values were calculated. The 24-hr urinary nitrogen and 3-methylhistidine excretion were measured. Indirect calorimetry was used to calculate fuel utilization. Insulin-like growth factor I concentrations increased in the treatment group from subnormal to normal values and remained increased despite discontinuation of growth hormone treatment (p = .02).Nitrogen balance differed between the groups upon admission:growth hormone group (3.9 +/- 4.1 g/day) vs. controls (13.8 +/- 5.4 g/day), but improved with growth hormone. This finding appeared independent of the imbalance between the groups. The 3-methylhistidine excretion was not different between the groups and did not change during growth hormone administration. Free fatty acids and glycerol concentrations increased during growth hormone treatment, but calculated fuel utilization did not change. During growth hormone treatment, insulin concentrations increased, due to the increased administration of insulin necessary for glycemic control. Side effects other than hyperglycemia were not observed.ConclusionsGrowth hormone administration in a heterogeneous group of critically ill nonseptic patients resulted in normalization of insulin-like growth factor I levels, even after cessation of growth hormone treatment. Nitrogen balance improved, but this change was transient. Hence, growth hormone affects nitrogen balance, probably partly independent of insulin-like growth factor I.(Crit Care Med 1995; 23:665-673)

ISSN:0090-3493    

出版商:OVID    

年代:1995

数据来源: OVID

摘要:

ObjectiveTo study if metabolic stress modifies the thermogenic effect of dobutamine.DesignProspective, increasing dose, pharmacologic study.SettingLaboratory of the Department of Intensive Care Unit at a university hospital.SubjectsTwelve normal volunteers.InterventionsDobutamine hydrochloride was infused to 12 healthy male volunteers starting at a dose of 2 micro gram/min/kg and gradually increased to 4 and 6 micro gram/min/kg. Each dose of dobutamine was infused for 20 mins. Metabolic stress was induced in six of the 12 volunteers using a triple hormone infusion (epinephrine, cortisol, and glucagon) before dobutamine, and was continued at a constant rate during the dobutamine infusion. The remaining six volunteers served as the control group and receiveDonly dobutamine.Measurements and Main ResultsOxygen consumption (VO2) was measured using a metabolic monitor. Arterial blood pressure was measured noninvasively, and cardiac output was monitored by Doppler echocardiography. Plasma concentrations of dopamine, norepinephrine, and epinephrine were measured in both groups. In the triple hormone group, blood was sampled to measure concentrations of insulin, glucagon, cortisol, free fatty acids, and glycerol to ensure the presence of a metabolic stress reaction. At the maximum dose, dobutamine induced a 19% increase (from 140 +/- 17 to 166 +/- 17 mL/min/m2) in VO2in the control group and an 11% increase (from 167 +/- 10 to 184 +/- 13 mL/min/m2) in the triple hormone group (p < .05 between the two groups) compared with baseline. No change in the respiratory exchange ratio was seen. The triple hormone infusion alone induced hypermetabolism, a marked hemodynamic response, and increased lipolysis.Conclusions10% to 15% increase in VO2in response to dobutamine may not be explained just by the thermogenic effect of the drug.(Crit Care Med 1995; 23:674-680)

ISSN:0090-3493    

出版商:OVID    

年代:1995

数据来源: OVID

摘要:

ObjectiveTo determine if treatment modalities (fluid, inotropes, and blood) would be altered based on preload measurements of right ventricular end-diastolic volume index measured by fast response thermodilution catheter, as compared with pulmonary artery occlusion pressure (PAOP).DesignA prospective clinical trial.SettingAn 11-bed surgical intensive care unit (ICU) at The Queen's Medical Center, an affiliate of the University of Hawaii Surgical Residency program.PatientsSurgical ICU patients who required pulmonary artery catheters, except those patients with arrhythmias or history of tricuspid valve disease.Interventions120 beats/min, urine output of <40 mL/hr, stroke volume of <40 mL/m2with oxygen delivery of <450 mL/min/m2, and lactic acidosis. Volume infusion was considered if PAOP was <18 mm Hg and right ventricular end-diastolic volume index was <140 mL/m218 mm Hg to prevent pulmonary edema. When PAOP and right ventricular end-diastolic volume index gave conflicting information, other clinical parameters were assessed to determine treatment.Measurements and Main ResultsTwenty-seven patients requiring 70 catheters were evaluated for the study. Thirteen patients with 46 pairs of data points completed the study. Fourteen patients were excluded from analysis due to irregular heart rate, poor quality of cardiac output at the time of volume infusion, or lack of major volume manipulation. PAOP and right ventricular end-diastolic volume index measurements agreed in 42 of 46 instances (PAOP of <18 mm Hg, right ventricular end-diastolic volume index of <140 mL/m218 mm Hg, right ventricular end-diastolic volume index was <140 mL/m218 mm Hg with right ventricular end-diastolic volume index of <140 mL/m2. A rigid abdomen accompanied hypotension, tachycardia and low urine output. Thus, a fluid bolus was administered, resulting in improved blood pressure, stroke volume, and heart rate.or=to10 cm H2O, to avoid the effects of high intrapleural pressure on PAOP readings. Cardiac output was measured at end-expiration, and stroke volume index and right ventricular end diastolic volume index were derived.ConclusionsIn this small sample of surgical patients with sepsis, adult respiratory distress syndrome, and hemorrhagic shock (n = 13), the additional information derived from right ventricular end-diastolic volume index did not change treatment in 43 of 46 instances. However, patients with increased intra-abdominal pressures may show misleadingly high PAOP despite low preload. These patients clearly benefitted from the additional information derived from ventricular volume measurements. Additionally, clinicians who are reluctant to take off-PEEP PAOP may also find this catheter useful.(Crit Care Med 1995; 23:681-686)

ISSN:0090-3493    

出版商:OVID    

年代:1995

数据来源: OVID

摘要:

ObjectivesTo compare the effects of intermittent intravenous administration and continuous intravenous infusion of famotidine on gastric pH in critically ill patients.DesignA prospective, randomized, crossover study of continuous infusion and bolus administration of famotidine in critically ill patients.SettingA 14-bed medical intensive care unit (ICU) of a 500-bed county hospital.PatientsMedical ICU patients requiring stress ulcer prophylaxis.InterventionsPatients were randomized to receive an equivalent dose of famotidine by continuous infusion or intravenous bolus for 24 hrs, and then were crossed over to the other arm of the study.Measurements and Main Resultsor=to4 over a longer time period than bolus administration (20.8 hrs vs. 12.6 hrs, respectively; p < .01). Onset of therapeutic gastric pH for continuous infusion was slightly delayed as compared with bolus administration.ConclusionsContinuous infusion of famotidine is more effective than an equivalent dose given by intermittent bolus in maintaining the appropriate gastric pH necessary for prevention of stress ulceration. Delayed onset of effect may warrant a priming dose when famotidine is given by continuous infusion.(Crit Care Med 1995; 23:687-691)

ISSN:0090-3493    

出版商:OVID    

年代:1995

数据来源: OVID

摘要:

ObjectiveTo determine if ultrasound guidance can be safely performed and improve success rates for subclavian venous catheterization performed by less experienced operators.DesignProspective, randomized study.SettingTwenty-bed trauma-surgical-medical intensive care unit in a 524-bed, community, tertiary care, teaching hospital.PatientsAfter the decision for central venous cannulation was made, informed consent was obtained, and less experienced operators then attempted to insert subclavian catheters in 33 critical care patients.InterventionsCatheter placements were attempted, either by landmark technique, ultrasound technique, or by landmark attempts with ultrasound salvage. Catheterization techniques to be used were randomized using a random number table.Measurements and Main ResultsFifty-three placement procedures were attempted in 33 patients. One procedure was excluded from data analysis. Successful catheterizations, occurrence rates of complications, number of attempts, and number of catheter kits used were recorded. In the analysis, 52 catheterization procedures were studied. Twelve (44%) catheters were successfully placed from 27 attempts using the landmark technique vs. 23 (92%) successful catheterizations during 25 ultrasound procedures (p = .0003). Fifteen failed landmark technique attempts had ultrasound salvage attempted, with 12 (80%) catheters successfully inserted. Eleven complications (minor) occurred in 27 attempts of subclavian venous catheterization using conventional landmark technique vs. one complication (minor) in 25 attempts of subclavian venous catheterization with ultrasound guidance (p = .002). There were no major complications in either group. The landmark group required an average of 2.5 venipunctures and 1.4 catheter kits per attempted catheterization. The ultrasound group required an average of 1.4 venipuncture attempts and 1.0 inserition kit. The statistical significance in differences in groups for the average number of venipunctures was p = .0007 and average number of kits used was p = .0003.ConclusionsUltrasound guidance improves the success rate of subclavian venous catheterization performed by less experienced operators. There were no major complications in either group. Ultrasound guidance is usually successful in allowing performance of subclavian venous catheterizations when landmark techniques fail.(Crit Care Med 1995; 23:692-697)

ISSN:0090-3493    

出版商:OVID    

年代:1995

数据来源: OVID

摘要:

ObjectiveThis study was done to assess the effects of temperature on bleeding time and clotting time in normal male and female volunteers.DesignOpen study utilizing normal volunteers.SettingUniversity research laboratory.SubjectsFifty-four healthy male and female volunteers, ranging in age from 19 to 35 yrs, who were not receiving medications. The study was done and the samples of venous blood and shed blood collected at the template bleeding time site were obtained at a convenient time for each volunteer.InterventionsSkin temperature was changed from +20 degrees to +38 degrees C and blood samples were obtained from the antecubital vein of each volunteer.Measurements and Main ResultsThe effect of local skin temperature ranging from +20 degrees to +38 degrees C on bleeding time was evaluated in 38 normal volunteers (19 male and 19 female). Skin temperature was maintained at +20 degrees to +38 degrees C by cooling or warming the forearm. At each temperature, measurements were made of complete blood count, bleeding time, and thromboxane B2concentrations in shed blood collected at the template bleeding time site and in serum and plasma isolated from blood collected from the antecubital vein. Clotting time studies were measured in 16 normal volunteers (eight male and eight female) at temperatures ranging from +22 degrees to +37 degrees C.At +32 degrees C, the bleeding time was longer and hematocrit was lower in female than in male volunteers.However, at local skin temperatures of <+32 degrees C, both the males and females exhibited significantly increased bleeding times, which were associated with a reduction in shed blood thromboxane B2. Each 1 degree C decrease in temperature was associated with a 15% decrease in the shed blood thromboxane B2concentration. Clotting times were three times longer at +22 degrees C than at +37 degrees C. Each 1 degree C reduction in the temperature of the clotted blood was associated with a 15% reduction in the serum thromboxane B2concentration.ConclusionOur data indicate that during surgical procedures, it is important to maintain normothermia to ensure that platelets and clotting proteins function optimally.(Crit Care Med 1995; 23:698-704)

ISSN:0090-3493    

出版商:OVID    

年代:1995

数据来源: OVID

摘要:

ObjectiveTo determine the effects of the inhibition of endothelium-derived relaxation factor in an animal model of neonatal group B streptococcal sepsis.DesignComparison of three experimental protocols: a) N-nitro-L-arginine; b) group B streptococcal; and c) group B streptococcal/N-nitro-L-arginine.SubjectsPiglets, 1 to 2 wks old.InterventionsEndothelium-derived relaxation factor inhibition was produced in nonseptic piglets by the infusion of a competitive inhibitor of nitric oxide synthase, N-nitro-L-arginine, at 30 mg/kg (N-nitro-L-arginine protocol; n = 6). Human group B streptococcal sepsis was modeled in piglets by the continuous infusion of live group B streptococcal organisms at approximate 5 times 109organisms/kg cumulative dose (group B streptococcal protocol; n = 8). Endothelium-derived relaxation factor inhibition during a group B streptococcal sepsis was produced by N-nitro-L-arginine infusion during continuing group B streptococcal infusion (group B streptococcal/N-nitro-L-arginine protocol; n = 7).Measurements and Main ResultsBoth N-nitro-L-arginine and group B streptococcal infusion significantly increased systemic and pulmonary vascular resistance and decreased cardiac output and oxygen delivery. N-nitro-L-arginine differed from group B streptococcal infusions in its effects on systemic blood pressure (BP) (N-nitro-L-arginine increased BP while group B streptococcal infusions did not), and pulmonary/systemic vascular resistance ratio (group B streptococcal infusions increased pulmonary/systemic vascular resistance ratio more than N-nitro-L-arginine did). The group B streptococcal/N-nitro-L-arginine group differed significantly from piglets receiving continued group B streptococcal infusion without N-nitro-L-arginine in cardiac output (significantly lower in group B streptococcal/N-nitro-L-arginine), oxygen delivery (significantly lower in group B streptococcal/N-nitro-L-arginine), and pulmonary vascular resistance (significantly higher in group B streptococcal/N-nitro-L-arginine).ConclusionsGroup B streptococcal sepsis in human newborns and in animal models of human newborns is characterized by a hemodynamic constellation of "cold shock''--increased vascular resistance and reduced systemic blood flow. Endothelium-derived relaxation factor inhibition during group B streptococcal sepsis in piglets exacerbated many of the adverse hemodynamic consequences of group B streptococcal infusion.We speculate that endothelium-derived relaxation factor inhibition has no foreseeable therapeutic role in neonatal septic shock.(Crit Care Med 1995; 23:705-714)

ISSN:0090-3493    

出版商:OVID    

年代:1995

数据来源: OVID