Candida albicans septic thrombosis of the right atrium is associated with a central venous catheter.

Right atrial thrombus formation is a rare complication of central venous catheterization in adults. Infection of this thrombus is exceptional. A case of a right atrial thrombus associated with Candida albicans infection is described. Surgical thrombectomy, withdrawal of the catheter, and long-term antiinfectious therapy seem the only appropriate treatment. The literature on this unusual condition is reviewed.

Hydrochloric acid infusion for treatment of metabolic alkalosis associated with respiratory acidosis.

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 PaCO2 in 15 critically ill patients admitted with mixed respiratory acidosis and metabolic alkalosis, and a pH of between 7.35 and 7.45. HCl was infused at a constant rate of 25 mmol/h until the bicarbonate concentration decreased less than 26 mmol/L, or until the pH decreased less than 7.35 (initial pH greater than 7.40) or 7.30 (initial pH less than 7.40). Administration of 170 +/- 53 mmol of HCl decreased the bicarbonate concentration from 34 +/- 3 to 25 +/- 2 mmol/L (p less than .001), the pH from 7.41 +/- 0.03 to 7.33 +/- 0.02 (p less than .001), and the PaCO2 from 54 +/- 8 to 48 +/- 8 torr (p less than .001). Postinfusion PaCO2 could be predicted accurately from the initial status of the patients (r = .95, p less than .001) except in one patient with fixed hypercapnia. PaCO2 increased from 77 +/- 19 to 94 +/- 24 torr (p less than .001) and PaO2/PAO2 increased from 59 +/- 17 to 66 +/- 17% (p less than .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 CO2 and oxygen exchange in critically ill patients with mixed respiratory acidosis and metabolic alkalosis.

Technical and psychological complications of high-frequency jet ventilation.

The type and the incidence of complications during treatment with high-frequency jet ventilation were evaluated in 10 critically ill patients with acute respiratory failure. HFJV was used for 2 to 34 days for management of bronchopleural fistulae, tracheal rupture, laryngeal trauma or voluminous lung abscesses. The most significant technical problems observed were disconnection or kinking of the jet catheter, hypothermia and CO2 retention. Insufficient humidification could induce severe complications such as viscous bronchial secretions, desiccation of the tracheobronchial mucosa or total obturation of the endotracheal tube. Psychological tolerance of high-frequency jet ventilation was generally satisfactory but the ventilator noise was sometimes hardly tolerated. Patients could develop a psychological dependence to high-frequency jet ventilation, leading to weaning problems. Solutions are suggested to decrease the incidence and severity of the technical and psychological complications.

Hydrochloric acid infusion for treatment of metabolic alkalosis: effects on acid-base balance and oxygenation.

The effects of hydrochloric acid (HCl) administration were studied in 15 critically ill patients whose metabolic alkalosis caused a significant alkalemia (pH 7.50 to 7.58) unresponsive to sodium and potassium chloride administration. Arterial pH and bicarbonate and chloride concentrations normalized after a 6- to 12-h mean infusion of 200 +/- 54 mmol of .25 N HCl. There were no deleterious vascular, hematologic, or metabolic side-effects. HCl administration was associated with an increase in mean PaO2 from 94 +/- 21 to 121 +/- 31 torr (p less than .001). This increase was comparable in patients breathing spontaneously and those treated with controlled mechanical ventilation, and was attributed at least in part to a decrease in pulmonary shunt. These results indicate that .25 N HCl, infused at the rate of 100 ml/h into the superior vena cava, can correct metabolic alkalosis safely and rapidly. The persistence of the beneficial effects of this treatment on arterial oxygenation remains to be confirmed.

Electromechanical dissociation after ventricular fibrillation: prevention with calcium-entry blockers.

Calcium-entry blockers were administered in an attempt to protect myocardium during cardiac arrest due to ventricular fibrillation in mechanically ventilated dogs. An intravenous injection of verapamil, nifedipine, or lidoflazine was administered prior to successively prolonged episodes of ventricular fibrillation, during which no thoracic compression was performed. It is of interest that ventricular defibrillation was more easily obtained after treatment with the three drugs. As previously observed in this model, nine control dogs developed electromechanical dissociation (EMD) after 120 seconds of ventricular fibrillation. In contrast, six of the 11 dogs treated with 0.3 mg/kg of verapamil recovered mechanical systole after 120 seconds of ventricular fibrillation (p less than 0.05). Nifedipine administration also postponed the onset of EMD in three of four dogs. However, lidoflazine postponed the onset of EMD in only one of the eight dogs. The later onset of EMD after administration of verapamil or nifedipine in this model was attributed to myocardial protection by calcium-entry blockers during ventricular fibrillation. Decreased energy utilization during cardiac arrest was considered to be the principal protective mechanism. These observations indicate calcium-entry blockers, and especially verapamil and nifedipine, can be valuable drugs during cardiac resuscitation for ventricular fibrillation.

Bretylium in severe ventricular arrhythmias associated with digitalis intoxication.

Bretylium has been well-recognized as an effective antiarrhythmic agent for acute ventricular arrhythmias, but its use is believed to be contraindicated in digitalis intoxication. We report of two patients in whom digitalis-induced malignant ventricular arrhythmias were refractory to lidocaine. One patient had had repeated episodes of ventricular fibrillation associated with digitoxin and quinidine intoxication, and one patient had had malignant premature ventricular beats associated with digoxin intoxication. Cardiac electrical activity was paced in both instances. In the two patients, ventricular arrhythmias rapidly resolved, and no side effect was encountered. These observations support the administration of bretylium for severe digitalis-induced ventricular arrhythmias.

Oxygen-carrying substitutes other than fluorochemicals.

Beside the fluorochemicals, the research for oxygen carrying blood substitutes is pursued in two directions: hemoglobin derivatives and oxygen-binding chelates. Trials with hemoglobin had to overcome the following difficulties: renal toxicity, leakage outside the intravascular compartment, high affinity for oxygen and intravascular clotting effects. For several of these untoward effects, a satisfactory correction has been found. Other substances studied for possible oxygen-carrying fluids are various metal chelates. Several of these appear to be promising compounds, whereas no chelate is yet ready for in vivo investigation.

Serial lactate determinations during circulatory shock.

The time course of lactacidemia was studied prospectively in 17 patients during fluid resuscitation for an episode of noncardiogenic shock, in 5 patients after grand mal seizures, and in 5 patients after successful CPR for cardiac arrest. The 9 patients in whom shock was reversed with fluid administration demonstrated a regular decrease in lactate concentrations, which exceeded 5% of the initial value during the first 60 min of treatment. In the other patients who expired despite similar therapy, lactacidemia was not significantly affected. During circulatory shock, repeated lactate determinations represent a more reliable prognostic index than an initial value taken alone. Changes in lactate concentration can provide an early and objective evaluation of the patient's response to therapy.

Acetate-induced myocardial depression during hemodialysis for acute renal failure.

We studied the cardiovascular effects of hemodialysis in five critically ill patients with ultrafiltration using, alternately, bicarbonate and acetate in the dialysate. After 3 hr of dialysis with acetate, significant decreases in both arterial pressure and stroke volume resulted in lowered left ventricular stroke work (P less than 0.025). This effect persisted 30 min after the end of the dialysis (P less than 0.025). Differences in the patients' cardiac preload were ruled out by similar pulmonary artery balloon-occluded pressures during both types of dialysis. These observations suggest that dialysis with acetate can result in myocardial depression. The use of bicarbonate dialysate is thus advisable for acute hemodialysis in critically ill patients.

[Comparison between the mobile emergency care systems of the Free University of Brussels and the Catholic University of Leuven]. / Comparaison entre les services d'aide médicale urgente de l'Université Libre de Bruxelles et la Katholieke Universitiet Leuven.

Populations concerned with mobile emergency care systems have the same age distribution in Leuven and in Brussels. Interventions for trauma are more frequent in Leuven and cardiac emergencies more frequent in Brussels, but these digfferences decrease when only critical patients are taken into consideration. The origin of calls is quite different in Brussels and in Leuven. The mobile emergency care system is underused in Brussels. The distribution of emergencies is influenced by the information and the formation of firemen, physicians and public.