[Experience with the first 10 cases of percutaneous tracheostomy carried out at the recovery unit]. / Experiencia con los diez primeros casos de traqueostomía percutánea realizados en la unidad de reaninación.

The indications for percutaneous tracheostomy (PT) are the same as those for conventional tracheostomy. First described in 1969, PT has gradually become more widely used. We analyze the first 10 cases in which the procedure was performed in our postoperative intensive care unit. PT was performed in 10 patients admitted to the postoperative intensive care unit needing tracheostomy, following the procedure of Cook (Bjaeverskov, Denmark). Complications appearing during the procedure or later in the study period were recorded. All 10 PT procedures were successful. The mean time was 11.9 min (+/- 5.9). Minor complications developed in 5 patients. In 3 of these, the problems were technical (stylete slipping out, cannula hitting the endotracheal tube, and difficult insertion of a prepared cannula). The other 2 complications were small hemorrhages in the tracheostomy. No episodes of hypoxemia occurred during PT. The only late complication was a tracheostomy infection in a patient. In our experience PT is a useful alternative to conventional tracheostomy. The technique is easy to learn and performed quickly. Complications that develop do not affect the ultimate success of threaten patient stability.

[Anesthesia in heart transplantation. Experience at the Clínica Puerto de Hierro]. / Anestesia en el trasplante cardíaco. Experiencia de la Clínica Puerta de Hierro.

The anaesthetic management of 41 patients who underwent cardiac transplantation during a 40 month period at Clínica Puerta de Hierro is reviewed. The study includes the preoperative assessment, anaesthetic agents used and intraoperative incidences. The anaesthesia was induced with etomidate whereas a high-dose fentanyl, supplemented with diazepam, was the most commonly anaesthetic technique used. There was no intraoperative mortality in this series. Several interesting concerns related to the physiology of the denervated heart and the effects of vasoactive agents after extracorporeal circulation are reviewed.

The diuretic properties of dopamine in patients after open-heart operation.

Dopamine and dobutamine were administered to 12 patients who had undergone open cardiac operations. To eliminate the effects of variation in systemic blood flow upon renal function the drug infusion rates were adjusted to achieve equal cardiac outputs. Under conditions of equivalent systemic pressure and flow, dopamine (5.0 +/- 1 micrograms X kg-1 X min-1) and dobutamine (3.5 +/- 1.8 micrograms X kg-1 X min-1) had similar effects upon glomerular filtration rate (90 +/- 29 vs. 83 +/- 27 ml X min-1 X 1.73 m-2) and effective renal plasma flow (375 +/- 119 vs. 357 +/- 126 ml X min-1 X 1.73 m-2). However, dopamine administration resulted in a significantly greater diuresis (2.8 +/- 2.7 vs. 1.0 +/- 0.3 ml/min), natriuresis (0.32 +/- 0.39 vs. 0.07 +/- 0.10 mEq Na+/min), and kaliuresis (0.15 +/- 0.06 vs. 0.10 +/- 0.03 mEq K+/min) (P less than 0.05). In patients with modest depression of cardiac performance and renal vasoconstriction, dopamine's selective renal vasodilator effects were not evident. Furthermore, these data suggest that dopamine inhibits tubular solute reabsorption directly. Thus, the diuresis and natriuresis that frequently accompany dopamine administration may occur independently of any effects of dopamine upon renal blood flow.

A new surgical technique for aneurysmal right atrium.

A new surgical technique for reduction in size of aneurysmal right atrium (ARA) is described. The extracorporeal perfusion is based on extrapleural single stage caval return and profound hypothermia, with circulatory arrest. This method enabled us to diminish the cavity dimensions in the presence of a giant friable ARA, by excising the thinned portion of the free atrial wall and double-layer closure of the remaining edges (close to the AV groove) to the crista terminalis.

Pulmonary function and tissue oxygenation studies during anesthetic induction with etomidate.

The modifications of pulmonary function and peripheral oxygenation arising during anesthetic induction with Etomidate were studied in 36 unpremedicated patients programmed for elective surgery. The evaluation was carried out through measurement of ventilatory parameters and of the blood gases and oxygen saturation in arterial and mixed venous blood, calculation of the cardiac output, and derivation of data of peripheral oxygenation. A global reduction of the minute volume was observed with a minimal effect on the blood-gas values. The arterial blood oxygenation was reduced during the anesthesia time due to increased alveolo-arterial oxygen gradients and to increased intrapulmonary shunt. The tissular oxygenation data evidenced no significant alterations.

Cardiac arrest due to digitalis intoxication with normal serum digoxin levels: effects of hypokalemia.

A case of cardiac arrest due to digitalis toxicity is described. The patient had normal serum digoxin levels and hypokalemia, and treatment with potassium chloride, phenytoin, and pacing was successful. Comment is made on the serum digoxin levels in relation to serum potassium.

The renal effects of sodium nitroprusside in postoperative cardiac surgical patients.

Sodium nitroprusside (SNP) is frequently used to control hypertension and/or improve systemic blood flow following cardiac operations. Although SNP causes renal vasodilation when infused into isolated kidneys, the reported effects of SNP on renal vascular resistance and blood flow in intact animals and humans have varied. To define the effects of SNP in postoperative cardiac surgical patients, renal clearances and hemodynamics were measured in seven patients within 24 hours of coronary bypass grafting. Studies were delayed until patients were stabilized and had rewarmed following operation. Following baseline measurements (off SNP), SNP infusion was used to lower mean arterial pressure to 85 torr. Pulmonary wedge pressure was maintained by appropriate fluid therapy, and the measurements repeated 1 h later. SNP administration resulted in equivalent decreases in renal (-31 per cent), pulmonic (-29 per cent) and systemic (-33 percent) vascular resistance. Notwithstanding the decrease in arterial pressure (109 +/- 14 to 91 +/- 9 torr, P less than 0.01), renal blood flow increased by 20 per cent (653 +/- 193 to 792 +/- 210 ml . min-1 . 1.73 m-2, P less than 0.02), in direct proportion to the increase in cardiac index (2.5 +/- 0.4 to 3.0 +/- 0.3 1 . min-1 . m-2, P less than 0.01). Thus, in postoperative cardiac surgical patients, SNP administration can be expected to improve renal blood flow, so long as left atrial hypotension is avoided, and the decline in systemic arterial pressure is not excessive. The improvement in renal blood flow achievable with SNP may be critical for patients with severely depressed left ventricular function in whom severe depression of renal blood flow may occur as an antecedent to acute renal failure.

Induction of anaesthesia with etomidate: haemodynamic study of 36 patients.

The haemodynamic effects of anaesthetic induction with i.v. etomidate have been assessed in 36 patients. The variables studied were recorded under basal conditions and 3 and 10 min after induction, before surgical stimulus. There was a reduction in cardiac output, stroke volume and arterial pressure, and a compensating increase in heart rate. Pulmonary arterial pressure and vascular resistance, central venous pressure and pulmonary capillary wedge pressure were virtually unchanged. Although etomidate has a negative inotropic effect, the variables which were depressed remained at all times within acceptable limits.