Bile duct ligation induced acute inflammation up-regulates cyclooxygenase-2 content and PGE2 release in guinea pig gallbladder smooth muscle cell cultures.

INTRODUCTION: This study examines hypotheses that BDL induces increased guinea pig gallbladder smooth muscle PGE2 release by up-regulation of COX-2. METHODS: BDL, Sham and Control Hartley guinea pig gallbladders were placed in cell culture, grown to confluence and underwent Western Blot analysis for smooth muscle cell content of COX-1, COX-2, Prostacylin Synthase, actin, caldesmon, vinculin, meta-vinculin and tropomyosin and were assayed for basal release of 6-keto-PGF(1alpha), PGE2 and TxB2 by EIA. RESULTS: BDL did not alter content of smooth muscle cytoskeletal proteins. BDL for 48 h increased smooth muscle cell release of PGE2 and 6-keto-PGF(1alpha) by 3-fold or more when compared to the Control and Sham groups. Western Blot analysis showed increased content of COX-2 in the BDL group. CONCLUSIONS: BDL for 48 h markedly increased endogenous guinea pig smooth muscle cell PG release, which was due to increased COX-2 synthesis.

Interleukin-6 levels in serum and lung lavage fluid of children undergoing open heart surgery correlate with postoperative morbidity.

OBJECTIVE: To evaluate the relationship of perioperative levels of interleukin 6 (IL-6) in serum and bronchoalveolar fluid with morbidity and mortality in children undergoing cardiopulmonary bypass (CPB). DESIGN: Prospective, noninterventional study. SETTING: Operating room and pediatric intensive care unit (PICU) of a university hospital. INTERVENTIONS: None. MEASUREMENTS AND RESULTS: IL-6 levels were measured in serum and lung lavage fluid obtained before, during, and after CPB using the B9.9 bioassay. Alveolar epithelial lining fluid (AELF) volume was calculated using the urea correction method. Mean intraoperative AELF IL-6 levels increased fourfold compared to preoperative levels, and mean serum IL-6 levels increased fivefold after CPB. Mean intraoperative AELF IL-6 levels correlated with intraoperative blood transfusion (r2 = 0.18; p = 0.049) and duration of inotropic support (r2 = 0.29; p = 0.009), mechanical ventilation (r2 = 0.24; p = 0.019), and PICU stay (r2 = 0.29; p = 0.008). Mean serum IL-6 levels 2 h after CPB correlated with intraoperative blood transfusion (r2 = 0.3;p = 0.007), and with Pediatric Risk of Mortality score on postoperative day 3 (r2 = 0.24; p = 0.022), and were higher in patients with massive fluid retention (p = 0.014) and in nonsurvivors (p = 0.003). CONCLUSIONS: Serum and alveolar IL-6 levels increase after CPB, and correlate with postoperative morbidity. Serum IL-6 levels also correlate with mortality. They may be useful in assessing the severity of the systemic inflammatory response after CPB.

Circulating neuropeptide Y in humans: relation to changes in catecholamine levels and changes in hemodynamics.

Neuropeptide-Y (NPY) is a sympathetic cotransmitter, which causes vasoconstriction, decreases coronary blood flow and decreases cardiac output. Circulating immunoreactive NPY (ir-NPY) levels increase with exercise, in patients admitted to the coronary care unit, and during thoracic surgery, and may play a role in postoperative hemodynamics. We studied changes in ir-NPY, epinephrine (E) and norepinephrine (NE) arterial plasma levels, and their correlation to simultaneous hemodynamic measurements at 8 perioperative time points in 13 patients undergoing open heart surgery. Changes in circulating ir-NPY negatively correlated with changes in systemic vascular resistance index (SVRI), mean arterial pressure (MAP) and mean pulmonary arterial pressure (MPAP) (P < 0.05), suggesting that the hemodynamic changes were the cause of the changes in ir-NPY levels, inducing overflow of NPY into the circulation via sympathetic activation. Changes in NE and E levels positively correlated with changes in heart rate (HR), SVRI and MPAP. Changes in E levels also positively correlated with changes in stroke volume index (SVI), central venous pressure (CVP) and cardiac index (CI). NE levels correlated well with E levels, but catecholamine levels did not correlate with ir-NPY levels. These results suggest, that the elevation in circulating NPY levels previously noted in patients with heart failure and acute myocardial infarction may reflect changes in NPY overflow and/or clearance secondary to increased sympathetic activity and to hemodynamic changes.

Initial evaluation of an intracorporeal oxygenation device.

We describe a recently developed intracorporeal gas transfer device, its potential applications and hazards. To date, patients with potentially reversible respiratory failure have been treated with controlled oxygen therapy and positive pressure ventilation, but this treatment may itself contribute to lung parenchymal damage from barotrauma and oxygen toxicity. Total or partial extracorporeal gas exchange can be used to reduce these risks, but this treatment is complex and has significant morbidity and mortality. This gas exchange device has been designed to provide partial gas transfer with simplicity of insertion and use. The oxygenator lies in the vena cava to provide prepulmonary gas exchange. In preliminary studies with three calves we have shown that the device increases both mean mixed venous and arterial oxygen content and reduces mean arterial carbon dioxide tension.

The use of an implantable left ventricular assist device following irreversible ventricular fibrillation secondary to massive myocardial infarction.

A TCI1 rough surface left ventricular assist device (LVAD) was implanted in a 47-year-old man who had sustained a recent massive myocardial infarction complicated by ventricular failure which remained unresponsive to intra-aortic balloon pump therapy and which was further complicated by irreversible ventricular fibrillation. Following implantation of the device and while awaiting a suitable donor organ for transplantation, further extension of the previous infarct resulted in left ventricular rupture and massive haemorrhage which led to his death. We report the successful use of the device in providing haemodynamic support, but caution against inordinate delay in bridging to transplantation patients who are at risk of extension of infarction.

Intrathecal morphine in cardiac surgery.

The effects of intrathecal morphine in 60 patients undergoing open-heart surgery were studied in an observer-blind control trial. The patients were randomly allocated into three groups of 20 each: (A) Control, (B) 2 mg and (C) 4 mg of intrathecal morphine. This study confirms that intrathecal morphine provides useful post-operative analgesia. Patients given intrathecal morphine required less postoperative analgesia and sedation and their respiratory function tests were less depressed than the control group. Since the completion of this study, reports have suggested that 1 mg of morphine intrathecally avoids the serious complications of respiratory depression. In the study described, the patients were electively ventilated post-operatively and respiratory depression was therefore not a problem. Of the other associated side-effects of intrathecal morphine, vomiting (20%) and pruritus (20%) proved the most troublesome.

Endocrinological effects of intrathecal morphine.

This study was designed to evaluate the metabolic effects of intrathecal morphine in patients undergoing coronary artery surgery. Ten patients received 4 mg preservative-free morphine in 6 ml saline intrathecally before surgery and were compared with 10 patients anaesthetised in a similar manner, though without intrathecal morphine. Catecholamines, cortisol and glucose measurements were made during surgery and for 24 h post-operatively. The control group had a higher post-operative requirement for papaveretum, indicating that intrathecal morphine provided some post-operative analgesia. In the period from end of surgery to 5 h after surgery, cortisol secretion was suppressed in the intrathecal morphine group.

The role of intensive plasma exchange in the prevention and management of haemorrhage in patients with inhibitors to factor VIII.

A strategy for the prevention and management of haemorrhage in patients with inhibitors to factor VIII by intensive plasma exchange and human factor VIII infusion is described. The advantages and disadvantages of this approach are discussed in the light of the authors' experience with the technique and the alternative methods of treatment described in the literature.

Cardiorespiratory changes following induction of anaesthesia with etomidate in patients with cardiac disease.

The cardiorespiratory effects of etomidate were measured in two groups of six patients with aortic or mitral valve disease. The induction of anaesthesia with etomidate 0.3 mg kg-1 was followed by a second dose 10 min later. After the first dose, a 19% decrease in systemic arterial pressure was associated with a decrease in systemic vascular resistance and left ventricular heart work. Cardiac index, pulmonary artery pressure and wedge pressure all decreased slightly. Central venous pressure and heart rate did not change. A slight increase in respiratory frequency failed to prevent an increase in PACO2. Changes after the second dose were similar. The two groups of patients did not differ significantly in their response to etomidate. No patient complained of pain during injection, nor did myoclonic movements occur.

Femoral artery pressure monitoring. Use of the Seldinger technique.

A case of bilateral femoral arterial occlusion following the Seldinger technique of arterial puncture for monitoring blood pressure is described. Sixty patients were closely studied for possible complications of this technique, using pedal blood pressure, and skin temperature to supplement clinical observation. Despite the occasional complications which are described we consider this to be a safe and valuable technique in selected circumstances.

A comparison of some cardiorespiratory effects of althesin and ketamine when used for induction of anaesthesia in patients with cardiac disease.

Cardiorespiratory effects of ketamine and Althesin were measured in two groups of premedicated patients with cardiac disease. The drugs were given in clinically equivalent doses with a second dose administered about 10 min after induction. The first dose of ketamine caused a marked increase in systemic and pulmonary arterial pressure, heart rate, and central venous and wedge pressures and cardiac index. The first dose of Althesin caused a decrease in systemic arterial pressure, central venous pressure, cardiac index and heart work, but little change in heart rate. The second dose of induction agent was administered before the cardiorespiratory effects of the initial dose had resolved. The second dose of Althesin caused changes similar to those following the first dose, but less marked. The changes following the second dose of ketamine were opposite to those following the first dose.

Cardio-respiratory changes during pneumoencephalography.

Carbon-respiratory changes associated with changes in posture and injection of intrathecal oxygen were studied in fifeen patients undergoing pneumoencephalography in a Phillips isocentric chair, while breathing spontaneously and anaesthetised with halothane in oxygen. Haemodynamic changes associated with changes in posture were of a minor nature. A rise in PaCO2 occurred in the prone position in two obese patients. There were significant rises in blood pressure following injection of more than 5 ml of oxygen as a bolus into the subarachnoid space.

Pulmonary damage from a Swan-Ganz catheter.

A patient developed pulmonary damage following the insertion of a Swan-Ganz catheter into the pulmonary artery. Suggestions are made on how to avoid this complication.