Management of the intraaortic balloon pump patient. Pharmacologic considerations

This article reviews the common pharmacologic agents used in conjunction with the IABP for treatment of LV failure. The complex interaction between the IABP and pharmacologic agents must be carefully monitored to optimize outcome in this critically ill patient group. It is important that ICU nurses be aware of the treatment goals and their rationale, as well as monitored parameters which detect, trend and predict the direction of hemodynamic change. By using these early indicators of hemodynamics, early information can be given to the physician and intervention can be implemented on a timely basis. Early and appropriate intervention can improve outcome in many patients and may ultimately reduce costs.     

Newly-developed catheter for cardio-renal assist during intraaortic balloon counterpulsation

A new catheter was developed for the cardio-renal assist during intra-aortic balloon counterpulsation. The catheter consists of both a large balloon of conventional IAB (TMP balloon) located at the distal end of the catheter and an additional small balloon 10 cm distant from the large balloon with common lumen and single shaft. Experimental study was carried out in the mock circulatory system simulating the descending aorta employing a conventional IAB catheter as a control. It was demonstrated that the flow in the mid portion between both balloons could be increased maximally by as much as 28% of that of the control under the continuous flow and 214% under the pulsatile flow. The double balloon catheter was considered to improve the renal perfusion as well as the coronary perfusion.     

Extensive bowel infarction caused by intraaortic balloon pumping

In breast cancer, oestrogen regulated genes, such as pS2, may be expressed in well differentiated tumours with a good prognosis. We have examined pS2 mRNA expression in 78 primary, untreated breast cancers and related pS2 expression to disease behaviour and known prognostic factors. pS2 mRNA expression was detected in 25/78 (32%) of cancers and was significantly associated with a moderate/high oestrogen receptor content (P = 0.045, Chi Square test). pS2 mRNA expression was associated with freedom from disease at median 31 months clinical and radiological follow-up (P = 0.015, Fisher's exact test, odds ratio 8.6). Using multiple logistic regression analysis of six potential prognostic factors only pathological axillary node status (P < 0.01) and pS2 mRNA expression (P < 0.05) provided independent prognostic information. Furthermore, pS2 was associated with a good prognosis in the axillary node positive patients where only 1/13 (8%) with pS2 mRNA expression compared with 13/29 (45%) without detectable expression had recurrence of their disease. These data provides strong support for pS2 as a useful independent prognostic factor in primary breast cancer.     

The effect of preoperative intra-aortic balloon pump support in high risk patients requiring myocardial revascularization

Differential scanning calorimetry (DSC), Fourier-transform infrared (FTIR) spectroscopy and transmission electron microscopy (TEM) have been used to determine the influence of beta-cyclodextrin (beta-CyD), hydroxypropyl-beta-CyD (HP-beta-CyD) and gamma-CyD on the structural properties of the stratum corneum from the hairless mouse. Some modest changes in the stratum corneum lipid transition temperature were induced by HP-beta-CyD and blue shifts were observed in the FTIR spectra of the C-H asymmetric and symmetric stretching of the lipids from the stratum corneum. Results from TEM studies indicated that HP-beta-CyD caused removal and possible disorganization of the lipid matrix that envelopes the corneocytes of the stratum corneum, whereas no effect was seen after treatment of the samples with beta-CyD and gamma-CyD. These results suggest that HP-beta-CyD can increase the permeability of the stratum corneum possibly as a result of extraction of lipids, and might thus enhance drug permeation through the skin.     

Prostaglandin E1 from the tip of an intraaortic balloon catheter for lower limb ischemia

A method to treat lower limb ischemia associated with the insertion of an intraaortic balloon catheter is herein reported. A low dose of prostaglandin E1 was administered into the descending aorta continuously from the tip of the intraaortic balloon catheter. Immediately after the administration of prostaglandin E1 in patients whose lower limbs were ischemic due to obstruction with the catheter, the peripheral circulation of the ischemic limbs recovered with minimal changes in the systemic arterial blood pressure. This method is simple and noninvasive and was found to induce a satisfactory effect.     

Changes of intraaortic balloon volume during pumping in a mock circulation system

The effects of hemodynamic changes on intraaortic balloon (IAB) volumes were studied experimentally using a helium tachometer in a mock circulatory system. The IAB volume decreased with increases in the heart rate and mean aortic pressure, but the degree of reduction in the IAB volume was different among 4 commercially available IAB drivers. Improvements in IAB consoles are needed to compliment the progress made in percutaneous techniques for IAB insertion resulting in smaller balloons.     

Neonatal piglet model of intraaortic balloon pumping: improved efficacy using echocardiographic timing

Secretoneurin (SN), a 33-amino acid neuropeptide, is derived from secretogranin II that is released from sensory afferent C-fibers by capsaicin. Described functions of secretoneurin include chemotaxis of monocytes and endothelial cells, and inhibition of endothelial cell proliferation. Inhibition of monocyte chemotaxis by staurosporine indicated involvement of specific signaling pathways. We have tested effects of SN, substance P (SP), and interleukin-8 (IL-8) on eosinophil migration in modified Boyden chambers including signaling mechanisms of neuropeptide and cytokine stimulation of human eosinophils. Experiments showed SN as eosinophil chemoattractant comparable in its potency to IL-8. Checkerboard analysis, usage of a specific anti-SN-antibody, and receptor desensitization experiments confirmed the chemotactic activity. Preincubation of the cells with effective concentrations of staurosporine or tyrphostin-23 showed no effect, whereas treatment with wortmannin (WTN) or 3-isobutyl-1-methylxantin (IBMX) completely blocked SN-induced migration. Additionally, experiments ruled out tyrphostin-23- and WTN-sensitive signaling pathways for SP-induced chemotaxis of eosinophils. We conclude that SN-stimulated human eosinophil chemotaxis is mediated via a unique and specific signal transduction pathway that involves activation of phosphodiesterases and WTN-sensitive enzymes, ie, phospholipase D and phosphatidylinositol-3-kinase. In contrast, we report that activation of the latter and tyrosine kinases is required for SP-induced chemotaxis of eosinophils.     

The development of indications for the preoperative use of recombinant erythropoietin

OBJECTIVE: To develop indications for the preoperative use of recombinant erythropoietin (rHuEPO) alone and in conjunction with preoperative autologous donation (PAD). DESIGN: A 2-round modified Delphi-consensus process. PARTICIPANTS: Nine physicians representing multiple clinical specialties, practice environments and geographic locations. METHOD: From evidence tables and a literature summary (MEDLINE database from January 1985 to August 1996) provided and using the RAND-UCLA appropriateness method, the physicians developed 264 indications for the preoperative use of rHuEPO by permuting 7 clinical factors (age, history of transfusion or antibody incompatibility, hemoglobin level, anemia of chronic disease, expected blood loss, presence of cardiovascular or cardiopulmonary disease and patient anxiety). These indications were rated on a 9-point appropriateness scale. Median scores and measures of agreement were determined. OUTCOME MEASURES: The significance of cost constraints or cost and blood supply constraints and the impact of each clinical factor on the ratings as judged by statistical analysis. RESULTS: Of the 264 indications, 54% were rated appropriate, 18% uncertain and 28% inappropriate. Expected blood loss had the greatest impact on the ratings (high expected blood loss had a 5.9 point more appropriate rating on the 9-point scale than low expected blood loss [p < 0.0001]). Preoperative hemoglobin level also significantly influenced the ratings (p < 0.0001). Compared with the clinical context, the ratings under the cost constraint were 1.0 less appropriate (p < 0.0001) for rHuEPO alone and 1.2 less appropriate for rHuEPO and PAD (p < 0.0001). The ratings for patients with moderate expected blood loss were significantly influenced by the cost constraint (less appropriate). CONCLUSIONS: Expected blood loss and preoperative hemoglobin level were the best indicators of rHuEPO appropriateness. Different contexts modify the appropriateness ratings of an expensive drug like rHuEPO.     

Effect of additional intraaortic balloon support during weaning from a left ventricular assist system

A safe and reliable method of weaning from a left ventricular assist system (LVAS) is necessary for successful circulatory support in patients with marginal heart failure. The purpose of this study is to assess the effect of additional intraaortic balloon (IAB) support during weaning from an LVAS by means of the LV pressure-volume relationship. A pneumatic LVAS with a sac-type blood pump was implanted in six adult mongrel dogs weighing 14 to 20 kg. All dogs had a drainage cannula placed in the left atrium and an outflow conduit in the ascending aorta. Hemodynamic parameters, pulmonary arterial flow, and pump output were monitored. An IAB was inserted through the groin. A conductance catheter and microtip manometer were inserted into the LV cavity. As a combination driving mode, LVAS ejection in the early diastolic phase and IAB inflation in the late diastolic phase were applied. After evaluation of baseline LV function, the pressure-volume relationship was repeatedly measured during change of driving modes as isolated LVAS, LVAS + IAB (1:1), LVAS + IAB (2:1), and isolated IAB supports. Finally, LV failure was introduced by stepwise ligation of left coronary arteries, and the LV pressure-volume relationship was measured in each driving mode. Under normal conditions, the pressure-volume loop showed no significant change among the four driving modes. In contrast, the LV pressure-volume relationship significantly improved according to the degree of additional IAB support on LVAS assistance under the condition of LV failure. These results suggest that additional IAB support might improve LV energy during weaning from an LVAS.     

Coronary sinus retroperfusion combined with intraaortic balloon pumping to perfuse the acutely ischemic myocardium

This study was planned to show the effect of retroperfusion and intraaortic balloon pumping (IABP) on myocardial hemodynamic recovery. Twelve dogs entered this study. Half of them received IABP and coronary sinus retroperfusion (CSPR) combination (Group II) and the remaining received IABP alone (Group I). Left anterior descending artery was occluded for a period of three hours. 15 minutes after occlusion IABP and IABP + CSRP were initiated. The average cardiac output was 1.41 +/- 0.18 L/min in the group I and 1.72 +/- 0.24 L/min in the group II (p < 0.03) after 3 hours of occlusion. Mean arterial pressure was 82.1 +/- 4.8 mmHg in the group I and 89.7 +/- 2.6 mmHg in the group II (p < 0.03). On the basis of this study it was concluded that CSRP + IABP could be an alternative treatment to IABP alone during the acutely developing ischemia.     

Left intraventricular balloon pump optimization during intractable cardiac arrest

This work aims to determine optimal balloon shape and volume during left intraventricular balloon pumping (IABP) in the fibrillating dog heart. A balloon volume equal to the left ventricular end-diastolic volume (LVEDV) maintained a higher systolic aortic pressure and flow (106.4 +/- 2.7 mmHg and 84.7 +/- 2.35 ml/kg/min, x +/- SEM, respectively) than a 25% smaller (97.8 +/- 3.3 mmHg, P = 0.002 and 63.7 +/- 4.1 ml/kg/min, P = 0.002, respectively) or a 25% larger balloon (87.4 +/- 2.3 mmHg, P = 0.002 and 70.9 +/- 3.4 ml/kg/min, P = 0.002, respectively). Among 5 different balloon shapes tested, a pear-shaped balloon inflated from the apex to the base of the left ventricle induced the highest (P varying from 0.042 to 0.01, compared to the remaining balloon shapes) systolic aortic pressure and flow (104.6 +/- 4.5 mmHg and 77.9 +/- 1.7 mg/kg/min, respectively). In conclusion, a pear shaped balloon, inflated to a volume equal to the LVEDV, from the apex to the base of the left ventricle, induced an optimal hemodynamic effect during LVBP.     

Glenohumeral arthroplasty: a critical review of indications and preoperative considerations

Total shoulder arthroplasty has become an effective treatment for advanced glenohumeral arthritis. The results depend, in part, on the underlying degenerative process. This article reviews the indications for glenohumeral arthroplasty, including important preoperative considerations. The different types of glenohumeral arthritides are discussed with respect to their clinical and radiographic manifestations, as well as their impact on preoperative planning.     

Hemodynamic profiles during concurrent intraaortic balloon pumping and venoarterial bypass--a canine study comparing subclavian and femoral artery perfusion sites

Concomitant use of venoarterial bypass (VAB) with centrifugal pump and intraaortic balloon pumping (IABP) is a common technique for cardiopulmonary resuscitation. This experimental study examines whether coronary perfusion and hemodynamics are affected by the site of the blood supply, comparing the subclavian artery and the femoral artery. VAB and IABP were performed in 11 mongrel dogs with cardiopulmonary failure induced by acute myocardial infarction and hypoventilation. Aortic root pressure (AP), left atrial pressure, central venous pressure and coronary sinus blood flow (CSF) were measured, and blood gas analysis was performed. Subclavian artery perfusion (SAP) and femoral artery perfusion (FAP) were compared at bypass ratios of 25, 50, 75, 85, 100%. At bypass ratios of 75% and 85% the mean systolic AP was higher with SAP than with FAP. The mean diastolic AP was higher with SAP than with FAP at a bypass ratio of 50% or higher. CSF was higher with SAP than with FAP at a bypass ratio of 50% or higher. The coronary arteriovenous O2 content difference was lower with SAP than with FAP at a bypass ratio of 85% or higher. In conclusion, at a high bypass ratio, SAP was more effective than FAP in achieving diastolic augmentation, thus enhancing myocardial oxygen balance, even though SAP had less of a systolic unloading effect. These data support the use of SAP over FAP in patients with severe cardiopulmonary dysfunction requiring high-flow bypass, and especially in patients with myocardial ischemia.     

Effects of intraaortic balloon pumping on septal arterial blood flow velocity waveform during severe left main coronary artery stenosis

OBJECTIVES: We sought to evaluate the effect of intraaortic balloon pumping on the phasic blood velocity waveform into myocardium with severe coronary artery stenosis. BACKGROUND: In the presence of severe coronary artery stenosis, it is not clear whether intraaortic balloon pumping augments intramyocardial inflow during diastole or changes systolic retrograde blood flow from the myocardium to the extramural coronary arteries. METHODS: Using anesthetized open chest dogs (n=7), we introduced severe stenosis in the left main coronary artery to reduce the poststenotic pressure to approximately 60 mm Hg (>90% diameter stenosis). Septal arterial blood flow velocities were measured with a 20-MHz, 80-channel ultrasound pulsed Doppler velocimeter. Left anterior descending arterial flow, aortic pressure and poststenotic distal coronary pressure were measured simultaneously. The diastolic anterograde flow integral and systolic retrograde flow integral were compared in the presence and absence of intraaortic balloon pumping. RESULTS: Although intraaortic balloon pumping augmented diastolic aortic pressure, this pressure increase was not effectively transmitted through stenosis. Septal arterial diastolic flow velocity was not augmented, and left anterior descending arterial flow was unchanged during intraaortic balloon pumping. CONCLUSIONS: In the presence of severe coronary artery stenosis, intraaortic balloon pumping failed to increase diastolic inflow in the myocardium and did not enhance systolic retrograde flow from the myocardium to the extramural coronary artery. Thus, the major effect of intraaortic balloon pumping on the ischemic heart with severe coronary artery stenosis may be achieved by reducing oxygen demand by systolic unloading.     

Clinical and hemodynamic criteria for use of the intra-aortic balloon pump in patients requiring cardiac surgery

In order to establish criteria for elective use of the intra-aortic balloon pump (IABP) in patients having cardiac surgery, we conducted a retrospective study of 43 patients who required counterpulsation, because of inability to be weaned from cardiopulmonary bypass, between May, 1972, and June, 1974. Patients in cardiogenic shock preoperatively were excluded. The 43 patients included 23 (Group A) who had severe preoperative left ventricular dysfunction with a mean cardiac index less than 1.8 L. per minute per square meter, ejection fraction less than 30 per cent, and end-diastolic pressure greater than 22 mm. Hg; 20 patients (Group B) had a combination of moderate cardiac dysfunction (cardiac index less than 2.2, ejection fraction less than 40, end-diastolic pressure less than 18) in the presence of acute infarction or severe aortic stenosis (gradient greater than 80 mm. Hg) with or without coronary disease. An inverse relationship was noted between survival and delay from completion of operation to the use of 1ABP. Thirty-two of 43 patients were weaned off bypass and were balloon assisted for 12 to 96 hours postoperatively; 25 patients were discharged (58 per cent). In Subgroup A, 14 of 23 (60 per cent) and, in Subgroup B, 9 of 20 (45 per cent) were long-term survivors. Based on these findings, 45 patients were operated upon between June, 1974, and December, 1975, with elective use of 1ABP and were assessed by serial hemodynamic studies. Sixteen had severe preoperative left ventricular dysfunction similar to Subgroup A and 29 had moderate dysfunction in combination with pathology similar to Subgroup B. Fifteen of these patients were hemodynamically unstable at time of arrival in the operating room; 1ABP was inserted under local anesthesia. Thirty-nine patients (87 per cent) were weaned off bypass and were hospital survivors. In Subgroup A, 13 of 16 (81 per cent) and, in Group B, 21 of 29 (72 per cent) were long-term survivors. Criteria for elective use of 1ABP in cardiac surgery should include severe preoperative left ventricular dysfunction or a combination of moderate dysfunction with coronary or valvular pathology. Elective 1ABP improves the survival with trivial iatrogenic morbidity.     

Detecting vascular problems in patients with diabetes treated with an intra-aortic balloon pump

Individuals with diabetes are at increased risk for both peripheral vascular disease and coronary artery disease. In patients with severe coronary artery disease, a cardiac assist device called an intra-aortic balloon pump (IABP) often is used to aid the failing heart and prevent further cardiac ischemia. Because this device is inserted via the femoral artery, patients are at risk of limb ischemia distal to the insertion site. Patients with diabetes are particularly prone to this complication. Detecting the early signs and symptoms of ischemia is crucial to preventing serious sequelae. Standard vascular examination techniques, in addition to being subjective and not easily reproducible, may be misleading in patients with diabetes. This article provides a review of the signs and symptoms of lower limb ischemia and noninvasive vascular tests that clinicians can use to evaluate lower extremity circulation. Also included are protocols for patient care during and after hospitalization, and two case studies of cardiac patients with diabetes who were treated with an IABP.