Abstract

In a prospective investigation of perioperative cardiac edema formation requiring a delayed sternal closure, we identified thrombin increase combined with a simultaneous decrease of factor XIII as a probable cause. After experimental studies additionally revealed that factor XIII could protect endothelial barrier function, we did another prospective randomized trial in which factor XIII or placebo was preoperatively substituted. The substitution finally showed distinct effects minimizing the incidence of myocardial swelling. Therefore, the clinical application of factor XIII may have a valuable therapeutic benefit in cases of leakage syndrome during extracorporeal circulation in congenital heart surgery.

Abstract

OBJECTIVE Both albumin and synthetic colloids such as hydroxyethyl starch (HES) solution are used to optimize hemodynamics in the critically ill. The influence of different long-term infusion regimes on platelet function was studied. DESIGN Prospective, randomized study. SETTING Clinical investigation on a university hospital surgical intensive care unit. PATIENTS Twenty-eight consecutive trauma patients (injury severity score > 15 points) and 28 consecutive nontraumatized surgical patients with sepsis. INTERVENTIONS The patients received either 20% human albumin (HA trauma, n = 14; HA sepsis, n = 14) or 10% low-molecular-weight HES solution HES 200/0.5 (HES trauma, n = 14; HES sepsis; n = 14) for 5 days to maintain central venous pressure and/or pulmonary capillary wedge pressure between 12 and 16 mmHg. MEASUREMENTS AND RESULTS Platelet function was assessed by aggregometry (= turbidimetric technique) using adenosine diphosphate 2.0 mumol/l, collagen 4 microliters/ml, and epinephrine 25 mumol/l as inductors. Arterial blood was sampled on the day of admission or the day of diagnosis of sepsis (= baseline value) and over the next 5 days. Standard coagulation parameters (antithrombin III, fibrinogen, partial thromboplastin time) were also measured. Total use of HES by the 5th day totalled 4870 +/- 990 ml in the trauma and 3260 +/- 790 ml in the sepsis patients (HA trauma: 1850 +/- 380 ml; HA sepsis: 1790 +/- 400 ml). Maximum platelet aggregation decreased significantly during the first 2-3 days after baseline in all groups. At the end of the investigation period, platelet aggregation variables had recovered and reached (or even exceeded) baseline values. Within the entire investigation period, the course of platelet aggregation variables did not differ significantly between HA and HES-treated patients irrespective of whether they were trauma or sepsis patients. CONCLUSIONS Alterations in hemostasis may occur for several reasons in the critically ill. Human albumin is the preferred first-line volume therapy in patients at risk for coagulation disorders. With respect to platelet function, volume replacement with (lower-priced) low-molecular-weight HES solutions can be recommended in this situation without any risk.

Abstract

Sufficient intravascular fluid therapy is of major importance in the treatment of the critically ill patient. The present study assessed whether the cardiorespiratory response of long-term volume replacement with low-molecular weight (LMW) hydroxyethyl starch solution (HES) differs from that of human albumin (HA). According to a randomized sequence, 30 trauma patients (injury severity score [ISS] between 15 and 30) and 30 sepsis patients (secondary to major general surgery) received either 10% HES (mean molecular weight 200,000 daltons; HES trauma [n = 15], HES sepsis [n = 15]) or human albumin 20% (HA trauma [n = 15], HA sepsis [n = 15]) over 5 days to keep pulmonary capillary wedge pressure (PCWP) between 12 and 18 mm Hg. Cardiorespiratory variables were measured by a pulmonary artery catheter on the day of inclusion into the study and daily during the next 5 days. Gastric intramucosal pH (pHi) was measured by tonometry. Central venous pressure and PCWP were comparable within the subgroups (trauma/sepsis) throughout the entire study period. In the trauma patients, cardiac index (CI), oxygen consumption index (VO2I), and oxygen delivery index (DO2I), significantly increased only in the HES-treated patients. In the sepsis patients, CI, VO2I, and DO2I increased and remained higher than baseline only in the HES group (P < 0.01). Right ventricular ejection fraction (RVEF) was reduced (< 40%) in the HA patients and increased only in the HES patients (from 34% +/- 4% to 42% +/- 3%; P < 0.05). pHi remained normal (> 7.35) in both trauma groups and in the HES-treated sepsis patients. In the HA sepsis group, pH, decreased (> 7.20) within the study period (7.15 +/- 0.12 on Day 4), indicating deteriorated splanchnic perfusion. We conclude that long-term intravascular fluid therapy with HA in traumatized and sepsis patients has no advantages in comparison to LMW-HES. In both groups, volume replacement with HES even resulted in improved systemic hemodynamics. Decrease in pHi in the sepsis patients was blunted by HES infusion indicating improved splanchnic perfusion by this regimen of volume therapy.

Abstract

To study the hemostyptic effect of aprotinin (Trasylol) in patients undergoing extracorporeal circulation for coronary artery bypass operations, we randomized 12 of 24 patients to receive aprotinin in high dosage (about 800 mg) during extracorporeal circulation. From the resulting two groups each, one patient was excluded from the study because of postoperative myocardial infarction (control group) and surgical hemorrhage (aprotinin group) leading to a second operation. Although heparin was used for anticoagulation in all 22 patients, all had a marked increase in plasma levels of thrombin-antithrombin III complexes during extracorporeal circulation, indicating an intravasal activation of coagulation. By monitoring the plasma levels of fibrin degradation products in patients without aprotinin therapy, we recorded a concomitant hyperfibrinolysis significantly less pronounced in patients receiving aprotinin (p less than 0.005). The mean total postoperative blood loss was lower in patients receiving aprotinin (620 ml) than in control patients (1000 ml; p less than 0.03). The results confirm previous reports of a hemostyptic effect of aprotinin in cardiac operations. This effect is probably due to a prevention of hyperfibrinolysis.