摘要:

The effects of intermittent positive-pressure ventilation (IPPV) with 0, 10, and 15 cm H2O of PEEP on inferior vena cava (IVC), right and left ventricular length and septal-lateral dimensions, and cardiac output were examined in 19 patients with respiratory failure using two-dimensional echocardiography. In five patients, cardiac output was also obtained by the thermodilution technique. As PEEP was increased, IVC dimensions increased during both inspiration and expiration, and the IVC collapsibility index decreased. This indicated an increase in venous stasis and decrease in venous return to the right atrium. Increasing PEEP was associated with progressive decreases in cardiac output, and length and septal-lateral dimensions of both ventricles. The decreased cardiac output during IPPV with 10 and 15 cm H2O PEEP may be due to the decreased venous return and ventricular filling. Cardiac output determined by echocardiography was correlated closely to that by the thermodilution technique.

ISSN:0090-3493    

出版商:OVID    

年代:1989

数据来源: OVID

摘要:

Gastric alkalization of critically ill patients is associated with bacterial and fungal overgrowth in gastric contents. We studied the incidence of gastric colonization and its relation to other infections and antibiotic therapy in 25 critically ill ICU patients. All patients received 12-h NG Mylanta II and 15 received an H2-receptor antagonist. All patients had bacterial colonization of NG contents within 4 days of ICU admission and 10 had Candida colonization within 8 days. There were 70 NG isolates and the same isolates were found in tracheobronchial secretions (n = 46), blood (n = 4), urine (n = 4), and wounds (n = 8). Tracheobronchial colonization was preceded by NG colonization with the same organism in 12 instances (11 patients), was concurrent with NG colonization in 20 instances (14 patients), was followed by NG colonization in 14 instances (11 patients), and had no similar NG isolate in 18 instances (11 patients). NG culture of the same organism preceded four of eight positive blood cultures. In 35 of 70 NG isolates and five of 11 subsequent tracheobronchial isolates, colonization occurred despite concurrent appropriate antibiotics. We conclude that colonization of alkalinized NG contents is universal, is a common source of infection in other areas, and is not prevented by systemic antibiotic therapy. Local antibiotic therapy may be important in controlling this important source of infection.

ISSN:0090-3493    

出版商:OVID    

年代:1989

数据来源: OVID

摘要:

Postoperative peripheral perfusion was studied in eight male patients undergoing coronary arterial bypass grafting. Transcutaneous Po2(Ptco2), subcutaneous tissue Po2(Psco2) and skin red cell flux (RCF) were recorded continuously in the upper extremity. In addition, peripheral and core temperatures, as well as central hemodynamic and some metabolic variables, were determined. The Fio2was maintained at 0.3. Complete opening of peripheral circulation occurred within a mean of 7 h after transferring the patients to the ICU. As the fingertip temperature rose, the Ptco3index, Psco2, and RCF underwent simultaneous increases, thereby reflecting reperfusion of the peripheral vascular bed.

ISSN:0090-3493    

出版商:OVID    

年代:1989

数据来源: OVID

摘要:

In a series of 56 patients (24 uncomplicated postoperative and 32 septic patients), neopterin and elastase α1protease inhibitor complex (E-α1, PI) plasma levels were measured daily. The clinical course of each patient was evaluated with the Mulitple Organ Failure (MOF) score according to Goris. Neopterin could differentiate between septic and nonseptic patients (p< .001), and E-α1PI between septic nonsurvivors and nonseptic patients only (p< .01). In septic patients, acute pulmonary insufficiency was indicated by elevated E-α1PI values (≥ 400 μg/L) 1 day before mechanical ventilation was performed with a sensitivity of 81 % and a specificity of 82%.Defining a patient with MOF whose score was ≥5 as a high-risk septic patient, a comparison neopterin ≥40 nmol/L and E-α1PI ± 400 μg/L, measured 1 day before the evaluation of an MOF score of ≥5 yielded a sensitivity of 91% and a specificity of 99% when patients fulfilled both criteria. We conclude that neopterin and E-α1PI might be useful parameters for the diagnosis of septicemia and monitoring of the clinical course in septic patients. Moreover, they might indicate the possible central role of macrophage and PMN activation in the development of MOF.

ISSN:0090-3493    

出版商:OVID    

年代:1989

数据来源: OVID

摘要:

Multiple rewarming methods have been recommended for the treatment of hypothermia in the ED. Because the hypothermic patient population is heterogenous, a method for stratifying mortality risk when comparing therapies is desired. We used univariable and multivariable statistical analyses to identify variables which discriminated between patient death or survival in the 24 h after arrival in the ED. Prehospital cardiac arrest, a low or absent presenting BP, elevated BUN, and the need for either tracheal intubation or NG tube placement in the ED were found to be significant predictors of patient demise in a large database (n = 428). The likelihood ratio was used to develop and validate an empiric hypothermia outcome score that can be used in future hypothermia treatment studies to account for differences of patient presentation.

ISSN:0090-3493    

出版商:OVID    

年代:1989

数据来源: OVID

摘要:

Hypercapnia due to respiratory failure can be more severe when accompanied by coexistent metabolic alkalosis. We therefore tested the hypothesis that hydrochloric acid (HCl) infusion could improve Paco2in 15 critically ill patients admitted with mixed respiratory acidosis and metabolic alkalosis, and a pH of between 7.35 and 7.45. HO was infused at a constant rate of 25 mmol/h until the bicarbonate concentration decreased <26 mmol/L, or until the pH decreased < 735 (initial pH > 7.40) or 730 (initial pH < 7.40).Administration of 170 ± 53 mmol of HCl decreased the bicarbonate concentration from 34 ± 3 to 25 ± 2 mmol/L (p< .001), the pH from 7.41 ± 0.03 to 733 ± 0.02 (p< .001), and the Paco2from 54 ± 8 to 48 ± 8 torr (p< .001). Postinfusion Paco2could be predicted accurately from the initial status of the patients (r = .95,p< .001) except in one patient with fixed hypercapnia. Paco2increased from 77 ± 19 to 94 ± 24 torr (p< .001) and Pao2/Pao2increased from 59 ± 17 to 66 ± 17% (p< .001). The effects of HCl were still present 12 h after the end of the infusion. No complications related to the acid infusion were noted. These results indicate that, even in the absence of alkalemia, active correction of metabolic alkalosis by HCl infusion can improve CO2and oxygen exchange in critically ill patients with mixed respiratory acidosis and metabolic alkalosis.

ISSN:0090-3493    

出版商:OVID    

年代:1989

数据来源: OVID

摘要:

End-tidal Pco2(Petco2) is a quantitative indicator of pulmonary blood flow generated by precordial compression and therefore predicts resuscitability during CPR. A striking increase in Petco2follows return of spontaneous circulation. Since Paco2is closely related to alveolar Pco2(Paco2) and therefore Petco2, we hypothesized that Paco2may itself serve as an indicator of the blood flow generated during CPR.In a porcine model of cardiac arrest, Paco2during precordial compression was highly correlated with Petco2(r = .89), cardiac output (r = .72), and coronary perfusion pressure (CPP) (r = .74). In 14 successfully resuscitated animals, Paco2, Petco2, and CPP during precordial compression were significantly higher than in nine nonresuscitated animals. After restoration of spontaneous circulation, there was a marked increase in Paco2to levels exceeding control values, which corresponded to the sharp increase in Petco2that is characteristic of successful resuscitation.We therefore confirm that both Petco2and Paco2correspond to the pulmonary blood flow and therefore cardiac output which is generated by precordial compression during CPR. Moreover, both serve as prognosticators of cardiac resuscitability and early indicators that spontaneous circulation has been restored.

ISSN:0090-3493    

出版商:OVID    

年代:1989

数据来源: OVID

摘要:

The effects of PEEP and subsequent augmentation of cardiac output by sodium nitroprusside (SNP) were examined in a canine model of asymmetric oleic acid injury to the right lung. PEEP (9.2 ± 0.5 cm H2O) was added to six animals to decrease venous admixture (Qsp/Qt) from 50.6 ± 4.4% to 16.0 ± 1.3 (p< .05). With PEEP, intrapulmonary blood flow distribution (assessed by radioactive microspheres) decreased significantly to nondependent lung regions while increasing to dependent regions. In six other animals, zero end expiratory pressure (ZEEP) did not alter intrapulmonary blood flow distribution. SNP was then administered to increase cardiac output by 40% (to 2.60 ± 0.21 L/min in the ZEEP group and to 1.75 ± 0.27 L/min in the PEEP group). SNP produced no adverse effects on Qsp/Qt or intrapulmonary blood flow distribution. Specifically, SNP did not preferentially dilate pulmonary vessels injured by oleic acid with or without end-expiratory pressure. Thus, administration of a vasodilator drug in asymmetric pulmonary edema appears well tolerated.

ISSN:0090-3493    

出版商:OVID    

年代:1989

数据来源: OVID

摘要:

Endotoxin protects against pulmonary oxygen toxicity in rats, and both prostaglandins and polymorphonuclear leukocytes (PMN) are implicated as playing an important role in this protective action. In this study, a bronchoalveolar lavage (BAL) technique was used to analyze cellular and eicosanoid composition of the lavage fluid of endotoxin-protected oxygen-exposed rats. The BAL fluid of the endotoxin-protected oxygenexposed rats contained the highest number of PMN, while the BAL fluid of the nonprotected oxygen-exposed rats contained the highest number of macrophages. Thus, morbidity due to pulmonary oxygen toxicity was correlated with the number of macrophages but not with the number of PMN present in the BAL fluid. Leukotriene B4, thromboxane B2, and prostaglandin E2levels were significantly higher in the lavage fluid of nonprotected oxygen-exposed rats compared to the levels in the lavage fluid of air-exposed rats. Eicosanoid levels in the BAL fluid of endotoxin-protected oxygen-exposed rats did not differ significantly from the levels found in air-exposed control rats. These findings suggest that endotoxin protects against hyperoxia-induced changes in eicosanoid metabolism.

ISSN:0090-3493    

出版商:OVID    

年代:1989

数据来源: OVID

摘要:

We compared the administration of sodium bicarbonate via a catheter inserted in the external jugular and extending to the junction with the subclavian vein (group 1) and a peripheral hindpaw vein (group 2) in puppies. During spontaneous cardiac activity, the increases in pH (0.12 ± 0.04 in group 1 vs. 0.08 ± 0.04 in group 2) and Pco2(11 ± 2.8 torr in group 1 vs. 6 ± 3.2 torr in group 2) in blood from the right atrium 10 sec after the injection of bicarbonate differed significantly. However, the increases in pH (0.31 ± 0.07 in group i vs. 0 .30 ± 0.15 in group 2) and Pco2(86 ± 33 torr in group 1 vs. 72 ± 35 torr in group 2) in blood from the right atrium during closed chest CPR were similar in the two groups. We found that the sodium bicarbonate reached the central circulation more rapidly when administered in the external jugular vein as compared to a peripheral site, but this difference was small and did not reach the level of significance during CPR. Our findings do not provide evidence of any advantage to obtaining central venous access (a potentially complicated procedure) in children with cardiac arrest in regard to the delivery of medications to the heart.

ISSN:0090-3493    

出版商:OVID    

年代:1989

数据来源: OVID