Successful treatment of a massive atenolol and nifedipine overdose with CVVHDF.

The aim of this paper was to describe a case of massive atenol and nifedipine poisoning, complicated by the co-existence of liver cirrhosis, where standard therapies (fluid replacement, vasopressors and inotropic agents, insulin, glucagon, calcium and bowel decontamination) were ineffective in restoring an adequate heart rate, blood pressure, renal and intestinal blood flow. This led to consequent anuric renal insufficiency and incipient multiple organ failure syndrome (MOFS). The patient recovered completely after Continuous Veno-Venous Hemo-Dia-Filtration (CVVHDF); this treatment removed atenolol from blood, with predicted clearance levels. The patient was a 45-year old female with a history of hypertension, liver cirrhosis, neurological and psychiatric disorders, with a massive atenolol (69.6 microg/mL) and nifedipine (63 ng/mL) overdose. CVVHDF at an ultrafiltration rate of 1 500 mL/h was started on day 1. From day 2 onwards, as the plasma atenolol concentration decreased, the blood pressure rose at a slow but constant rate. On day 5, there was restoration of an adequate blood pressure, which restored both renal and intestinal function, and also improved MOFS. The standard therapeutic approach was ineffective at eliminating both substances from the blood, and the clinical picture became worse due to incipient MOFS. CVVHDF was used in order to maintain the fluid and electrolyte balance and also to clear the beta blocker from the blood. The clearance kinetics of atenolol were consistent with the expected clearance values, on the basis of a CVVHDF ultrafiltration flow of 1 500 mL/h, which corresponds to a creatinine clearance of about 25 mL/min.

[Monitoring of cuff pressure in double-lumen endotracheal tubes during anesthesia for thoracic surgery]. / Il monitoraggio della pressione di cuffia in tubi endotracheali a doppio lume durante anestesia per chirurgia toracica.

It is well known that cuff overinflation in endotracheal tubes may cause serious damage to the tracheal mucosa. Cuff overinflation is also related to the diffusion of nitrous oxide across the cuff membrane, thus giving way to a progressive volume/pressure increase up to overcoming, critical capillaric perfusion pressure. The kinetics of hi-lo cuff-pressure in single-lumen endotracheal tubes during general anesthesia using nitrous oxide has been well documented. The authors have investigated the cuff-pressure modifications in 40 left double-lumen tubes (DLTs), monitoring the inflation pressure for both the endotracheal and endobronchial cuffs at the sealing of the airways and at different phases of the anesthetic procedures performed using nitrous oxide, in 40 male patients undergoing thoracic surgery. In ten of these case, special equipment was used in order to keep the cuff-pressures steady and at the lowest sealing level. The pressure shows the same trend in both cuffs but, depending on the medium calibre of the main left bronchus and the volume/pressure relations of the endobronchial cuffs, the pressure in the latter increases faster. The investigation was performed using an original equipment developed by the authors; such equipment is able not only to monitor the cuff-pressures, but also to maintain them at steady controlled levels (below 20 cm water seal), by means of counterregulating all the volume variations due either to anesthetic requirements, or to the diffusion of nitrous oxide.(ABSTRACT TRUNCATED AT 250 WORDS)