摘要:

The need for the prophylactic insertion of a pacemaker before pulmonary artery catheterization in patients with pre-existing left bundle-branch block (LBBB) is controversial. To determine the incidence of new right bundle-branch block (RBBB) and complete heart block during bedside pulmonary artery catheterization, 293 patients undergoing 307 pulmonary artery catheterizations were prospectively studied. Nine patients had pacemaker rhythms and 19 patients had an RBBB on their precatheterization ECGs and therefore were exluded from analysis. In the remaining 279 pulmonary artery catheterizations, eight (3%) were associated with the development of a new RBBB. None of the 14 patients with a pre-existing LBBB developed complete heart block. The incidence of complete heart block during pulmonary artery catheterization of patients with previous LBBB was not higher than the incidence of RBBB in patients without underlying conduction defects. Because of the rare but grave consequences of RBBB in patients with pre-existing LBBB, we recommend the use of standby external pacemakers and equipment for transvenous pacemaker insertion in these patients during pulmonary artery catheterization. We do not recommend prophylactic pacemaker insertion.

ISSN:0090-3493    

出版商:OVID    

年代:1989

数据来源: OVID

摘要:

We reviewed the ICU courses of 50 bone marrow transplant recipients treated for respiratory problems. Seven of nine postoperative patients survived compared to one of 40 patients with progressive interstitial pneumonia. Nonsurvivors accounted for 94% of the ICU days, 98% of intubated days, and 99% of blood products used. All survivors were extubated within 4 days. Intensive respiratory care is effective for patients with readily reversible causes of respiratory failure, but is generally futile for patients with progressive interstitial pneumonia. We recommend providing these patients with realistic prognostic estimates early in their treatment.

ISSN:0090-3493    

出版商:OVID    

年代:1989

数据来源: OVID

摘要:

We compared CVP and pulmonary capillary wedge pressure (WP) measurements with left atrial pressure (LAP) in postcoronary bypass surgical patients with preserved cardiopulmonary function. Measurements were obtained under normal conditions and conditions likely to induce WP-LAP discrepancies (PEEP and catheter tip malposition). Patients were in both supine and lateral positions; the catheter tip was placed vertically below (tip down; n = 12) or above (tip up; n = 5) the left atrium. Our data showed that both CVP and WP correlated well with LAP at all PEEP levels in the supine and tip down lateral positions. However, in the tip up lateral position, WP overestimated LAP (13.3 ± 3.4 vs. 8.0 ± 2 mm Hg; p < .01) at 20 cm H2O of PEEP, whereas CVP (8.8 ± 2.1 mm Hg) closely reflected LAP. Thus, by placing the catheter tip vertically below the left atrium in supinely and laterally positioned patients, CVP and WP both produced reliable estimates of LAP despite an acute increase in alveolar pressure. When the pulmonary artery catheter tip was vertically above the left atrium, WP overestimated LAP. Under these conditions, CVP remained a reliable estimate of LAP. We conclude that CVP measurement as an estimate of LAP in this patient population could be used and not ignored. This is true in patients with previously documented good LAP-CVP correlation who are subjected subsequently to conditions which may produce an LAP-WP discrepancy (high PEEP and catheter tip malposition).

ISSN:0090-3493    

出版商:OVID    

年代:1989

数据来源: OVID

摘要:

We report that the pediatric cardiogenic shock and septic shock populations show similar hemodynamic and oxygen utilization physiologic relationships during aggressive intensive care therapy. We examined the mathematical relationships between vascular tone and flow, and oxygen utilization and oxygen delivery (DO2) in the early and middle stages of cardiogenic and septic shock. The fitted curves between cardiac index and systemic vascular resistance, and oxygen consumption (VO2) and DO2were clinically and statistically similar in both shock populations. We found no evidence for decreased oxygen extraction in sepsis as compared to the cardiogenic shock population. In addition, it appears that the major determinant of VO2in these populations is DO2, not oxygen extraction. We suggest that patients with cardiogenic or septic shock can be treated according to similar physiologic principles.

ISSN:0090-3493    

出版商:OVID    

年代:1989

数据来源: OVID

摘要:

Modifications of the Physiologic Stability Index (PSI) and Therapeutic Intervention Scoring System (TISS) were used to evaluate the physiologic stability and need for therapeutic intervention in 55 infants hospitalized in the newborn ICU. After modifying the PSI to reflect neonatal physiology, we found that PSI scores correlated significantly with TISS values (r = .75,p< .001) and Nursing Utilization Management Intervention System (NUMIS) classifications (r = .62,p< .001). TISS values also correlated with NUMIS scores (r = .72,p< .001). PSI and TISS scores increased significantly with each increase in NUMIS classification(p< .001 for all comparisons). PSI and TISS scores decreased significantly between admission and either discharge (n = 41) or day 14 of hospitalization (n = 14,p< .001). PSI and TISS scores were greater on days 1 and 5 in infants with hyaline membrane disease when compared with infants with transient tachypnea(p< .001). Infants with PSI scores ≥4 and TISS scores ≥7 on day 1 took significantly longer to achieve adequate protein-calorie intakes than infants with lower first-day scores (p< .002). The modified PSI and the TISS scoring systems are both useful objective measurements of the degree of physiologic instability in newborn infants requiring intensive care, and both scores identify those at increased risk for nutritional morbidity.

ISSN:0090-3493    

出版商:OVID    

年代:1989

数据来源: OVID

摘要:

Patient awareness of intermittent positive-pressure ventilation (IPPV) treatment in the ICU was studied in 304 patients. These ICU patients were divided into three groups: those treated for internal medical diseases (IMD; n = 129), patients admitted after major surgical procedures (MSP; n = 126), and patients treated for trauma (T; n = 49). All patients were interviewed 2 months to 4 yr after IPPV treatment. The IPPV period was recalled by 52% of all patients. The awareness of the treatment was similar in the IMD (51%) and MSP (59%) groups, but was significantly lower in the T group (37%; p < .01). The ability to recall the IPPV treatment was reduced in patients with head injuries, those unconscious on admittance, and in elderly individuals. Treatment awareness was found to increase with the duration of the IPPV period in the IMD and T groups. Preoperative information of the treatment, given to elective surgical patients in the MSP group, did not increase treatment awareness.

ISSN:0090-3493    

出版商:OVID    

年代:1989

数据来源: OVID

摘要:

Sixty children aged 6 wk to 10 yr were studied. The children were undergoing cardiopulmonary bypass (CPB) for correction of congenital heart defects. The aim of the study was to provide prophylaxis for stress-induced gastric ulceration by elevating the gastric pH to at least 3.5. Two infusion regimes of ranitidine were compared: 0.1 and 0.2 mg/kg-h. The period of study was from induction of anesthesia until the end of the first 24 h after surgery. Both regimes were effective. The 0.2-mg/kgh infusion produced a significantly higher plasma concentration of ranitidine throughout the study period without any additional clinical benefit. Both regimes produced, within 3 h of cessation of CPB, a significant elevation in mean gastric pH to at least 5.3. This paper concludes that 0.1-mg/kgh infusion of ranitidine is a safe and efficacious regime for the critically ill pediatric patient.

ISSN:0090-3493    

出版商:OVID    

年代:1989

数据来源: OVID

摘要:

Histamine has been suggested as an important mediator of the cardiovascular abnormalities during septic shock. To determine if blood histamine levels were increased during human sepsis and septic shock, plasma histamine was measured using a very sensitive radioenzyme assay employing histamine N-methyltransferase (HNMT) in the following patient groups: normal controls (n = 76), nonseptic critically ill (n = 12), nonseptic shock (n = 2), sepsis without shock (n = 28), and septic shock (n = 41). Using this enzyme binding assay, all these groups had similar, normal plasma histamine concentrations, except those patients with septic shock whose mean histamine measurements were significantly reduced (p< .002). This decrease was found to be due to an artifact of the assay: plasma contained a circulating inhibitor that falsely lowered the measured histamine level. Fractionation of septic shock plasma using molecular exclusion membranes and gel filtration revealed a 5000 MW inhibitory factor. After removal of this inhibitor from plasma, septic shock plasma histamine levels were normal. Thus, septic shock patients may have a circulating inhibitor of the HNMT enzyme, but plasma histamine concentrations are normal. Histaminemia is unlikely to play an important role in the pathogenesis of septic shock in humans.

ISSN:0090-3493    

出版商:OVID    

年代:1989

数据来源: OVID

摘要:

Two commercially available pulse oximeters were found to read reliably early during periods of low cardiac index (CI) and low peripheral temperature (Tp). The lowest mean CI and mean Tp values at which a reading could be obtained were 2.4 L/min m: and 26.5°C. respectively. The highest mean systemic vascular resistance index was 2930 dyne -sec/cm5m2. The reliability of one monitor was equally good both in a normal and low perfusion mode (i.e. when the monitor displayed a low-quality signal message). The use of locally applied vasodilating creme widened the physiologic limits within which reliable measurements could be obtained. All oximeters and sensors overestimated slightly the saturation as compared to the hemoximeter readings. possibly because of a high mean carboxyhemoglobin concentration that was found to be present.

ISSN:0090-3493    

出版商:OVID    

年代:1989

数据来源: OVID

摘要:

Effects of PEEP on cardiac function, myocardial blood flow (MBF) and myocardial oxygen consumption (mVO2) were studied in eight mongrel dogs anesthetized with pentobarbital. Myocardial oxygen demand was increased by isoproterenol infusion or atrial pacing, or decreased by β-receptor blockade. PEEP was set to 15 cm H2O in all groups. The greatest reduction in cardiac output due to PEEP was seen during isoproterenol infusion (44%), and the smallest during β-receptor blockade (18%). This is attributed to increased sensitivity to the reduced left ventricular (LV) preload induced by PEEP, when cardiac inotropy is augmented by isoproterenol, compared to normal and reduced cardiac inotropy. PEEP decreased MBF similarly and significantly in all groups. However, myocardial oxygen extraction did not increase, and reduction in MBF caused by PEEP was closely related to concomitant reduction in mVO2;A significant correlation was also observed between reductions in I.N work and reduction in mVO2when PEEP was applied in all groups. We conclude that the reduced MBF observed with use of PEEP was probably due to reduced myocardial oxygen demand.

ISSN:0090-3493    

出版商:OVID    

年代:1989

数据来源: OVID