Presumptive delayed gas embolism after laparoscopic cholecystectomy.

A 50-year-old woman, with a history of arterial hypertension treated with beta-blocker and Ca-antagonist, presented cardiac arrest 6 hours after elective laparoscopic cholecystectomy. During surgical intervention, arterial hypotension without any respiratory change was observed. Dyspnea, asthenia and anxiety were the clinical signs appearing approximately 2 hours before cardiac arrest. After resuscitation, myocardial infarction, dissecting thoracic aortic aneurysm and major pulmonary thromboembolism were excluded. The signs of increased resistance to the right ventricular outflow and the relevant alteration of coagulation tests, lasting only a few hours, suggested venous gas embolism. Subsequently, the patient presented a cortical blindness, persisting at hospital discharge. The anesthetists should be aware about the complication that we observed after laparoscopic surgery. The least sign of cardiorespiratory instability appearing in the postoperative period must be taken into account and signal the need for increased monitoring.

Plasma dopamine concentration and effects of low dopamine doses on urinary output after major vascular surgery.

To evaluate plasma dopamine concentration and the effects of low doses infusion on urinary output after abdominal vascular surgery in patients with renal function impairment we performed a prospective clinical study. Twenty hemodynamically stable patients (mean age 66.6 years), with serum creatinine concentration < 2 mg %, who undergoing general anesthesia for major vascular surgery participated. A low dose of dopamine (3 micrograms/kg/min) was administrated to patients with postoperative protracted urinary output < 0.5 ml/kg/hr for at least eight hours. Plasmatic determinations were taken at T0 (no dopamine administration), when urinary output began to increase, or if not, after two hours (T1), at eight (T2), and 24 (T3) hours after the beginning of infusion. After 24 hours the dopamine infusion was stopped and the patient's plasmatic level was measured four hours later (T4). Dopamine plasma concentrations were measured using high-performance liquid chromatography. Plasma dopamine concentration increased in all patients and reached a steady state at T2 (T2 = 76.41 +/- 16.84 ng/ml). Dopamine induced a concentration-dependent increase in urinary output (T0 = 0.45 +/- 0.14; T1 = 1.49 +/- 1.11; T2 = 2.34 +/- 1.44; T3 = 1.57 +/- 0.57; T4 = 0.85 +/- 0.7 ml/kg/hr). Three patients did not have an enhanced urinary output after dopamine infusion; they did have a prolonged clamping time and operation time (162 +/- 24 and 570 +/ 30 min, respectively). We conclude that low dose dopamine induces a dose-dependent increase of urinary output. This phenomenon also has been found in patients when their plasma concentration had not yet reached the steady-state. Lack of responsiveness to dopamine suggests a renal function impairment probably due to the prolonged aortic clamping time.

[Low T3 syndrome (3,3',5-triiodothyronine) in relation to the extent of surgical trauma]. / La sindrome da basso T3 (3,3', 5-triiodotironina) in relazione all'entità del trauma chirurgico.

Thirty patients undergoing extra-thyroid surgery were divided into two groups (A and B) according to the extent of surgical stress (Group A: major surgery; Group B; minor surgery). Thyroid hormone levels were measured before the operation and up to the 3rd postoperative day in Group B and up to the 7th postoperative day in Group A. A low T3 syndrome was observed in all 30 patients examined of the first postoperative day (reduction of T3 and increase in rT3 without alterations of total thyroxin or signs of hypothyroidism) with normalisation of thyroid values by 3rd postoperative in Group B and later in Group A. The persistence of the syndrome in the latter group was due to the extent of surgical stress, the duration of anesthesia, the presence of stress factors such as staying in intensive therapy, painful symptoms and a negative energy balance during the first days following operation. This syndrome is indicative of a physiological adaptation process to reduce O2 consumption, basal metabolism and in particular protein catabolism.

Thrombosis of the superior vena cava due to a central catheter for total parenteral nutrition.

Total parenteral nutrition (TPN) today is a fundamental procedure in the treatment of critically ill patients, especially if they have serious gastrointestinal diseases. However, use of the central venous catheter is connected with a very important morbidity. At the "Istituto di Patologia Chirurgica" and at the "Intensive Care Unit" of the University of Ferrara, we analyzed 59 cases of deaths from different diseases, on whom a postmortem examination had been performed. Twenty-seven patients had had no central venous catheter: none of them presented thrombosis of the central veins. Thirty-two patients had had a central venous catheter for TPN: five of them presented thrombosis of the central veins at the post-mortem examination. Except for one case who had thrombosis connected with a carcinoma of the right main bronchus, four cases (12.9%) presented thrombosis due to the central venous catheter. The subclavian vein seems to be more commonly connected with thrombosis than the jugular vein.

[Severe arterial spasm and secondary thromboses of the limbs in chronic ergotism]. / Grave arteriospasmo e trombosi secondarie agli arti da ergotismo cronico.

A 40 year old woman who took a daily dose of 2-4 mg of Ergotamine Tartrate (Cafergot) regularly for 6 years to combat persistent migraine, was treated for a non-atherosclerotic arterial disease, severe arteriospasm of the great limb arteries, hyperplasia of the intima and segmental thrombosis. Binding of adrenergic alpha and beta receptors was investigated. Surprisingly it was found that the number of adrenergic beta receptors was significantly lower thant that of a healthy woman of the same age used as a control while the number of alpha receptors was not significantly different. This action of ergotamine on beta receptors could be explained by a dopamine-mimetic stimulation, due to the central nervous system, that could lead to the preferential regulation of beta receptors rather than alpha receptors, almost as a protective mechanism of alpha receptors.