[Systemic and pulmonary vascular resistance in brain death]. / Resistenze vascolari sistemiche e polmonari nella morte cerebrale.

BACKGROUND: Hemodynamic instability is known to affect brain dead subjects and it can be dangerous for the viability of transplantable organs. Aim of the present study was to assess the hemodynamic performance in brain dead subjects, the changes during the legal observation period and the results of therapeutic management. METHODS: The authors evaluated 28 consecutive adult brain dead subjects, all in intensive treatment, controlled ventilation, infusion therapy and/or dopamine administration and continuous direct monitoring of arterial pressure. Ten hemodynamic parameters have been registered by the thermodilution method and the Swann-Ganz catheter. The Legal Committee performed measurements at the beginning (T0) and the end (T6) of the observation period, which lasts 6 hours according to the current law on death certification (Law N. 578/93). RESULTS: Low systemic and pulmonary vascular resistances have been documented in the majority of subjects (75%), both treated only with fluids and with the additional dopamine administration (dosage lower than 10 ug/Kg/min). The above-mentioned reduction was similar at the two different monitored times (T0 and T6). CONCLUSIONS: This situation can be ascribed to the destruction of the cerebral vasoactive centers and the consequent hypotension is due to autonomic nervous system dysfunction. Hemodynamic instability must be treated by fluids and inotropic drugs, but they may cause cardiac and respiratory problems, thus it is suggested to use also low doses of vasoconstrictive drugs, provided that cardiac condition allows this therapeutic strategy.

[Hormone evaluation in brain death]. / Alcune valutazioni ormonali nella morte cerebrale.

BACKGROUND: In this study, the level and the variation of a number of hormone and metabolic parameters during brain death treatment in potential organ donors have been monitored. METHODS: Thirty-nine consecutive brain-dead patients were enrolled in 3 Intensive Care Units of Regional Hospitals of the North of Italy. All patients were potential organ donors and free from diseases before the accident leading to death. The levels of ADH, ACTH, TSH, prolactin, cortisol, aldosterone, FT3, FT4, renin, serum lactate and plasma osmolality were measured immediately after the diagnosis of brain death (T0), certified following the Italian law of December 29, 1993, n. 578, and after 6 hours (T6). RESULTS: Hormone levels were normal in the majority of subjects, and there was no significant variation during the 6 hours of the observation period. No correlation was found between the hormone levels considered and the metabolic parameters; ADH levels were not correlated with plasma osmolality. FT3 levels were below the normal range in the majority of subjects, but were not associated with a higher lactate level, which is used as a marker of a shift toward tissue anaerobic metabolism. CONCLUSIONS: In conclusion, triiodothyronine administration to improve metabolic order and thus the function of organs for transplantation is not justified in brain-dead patients.

Organizational aspects of donor procurement activity in the North Italy Transplant programme (NITp).

In Italy, organ procurement is insufficient to meet patient need. The aim of this study was to estimate the potential donor pool, quantify nonused donors, identify causes of nonretrieval, and evaluate the impact of some hospital organizational problems on organ procurement. In 1995 a questionnaire was sent to 103 intensive care units (ICUs) in 92 hospitals of the NITp area. Out of 432 potential donors identified, 239 (55.3%) were used. Causes of nonretrieval included family refusal (51.7%), clinical reasons (43.9%) and organizational problems (4.4%). In comparison with 1990 and 1993 data, a higher percentage of donors were used and the donors lost for organizational reasons had decreased significantly, while no significant differences were observed in the number of donors lost for family refusal and for clinical reasons. The marked improvement in donor procurement in NITp from 1990 to 1995 was probably as result of measures aimed at motivating ICU personnel and solving their organizational difficulties.

Maintenance of and recovery from anaesthesia in elderly patients. A clinical comparison between sevoflurane and isoflurane.

BACKGROUND: The goal of this multicenter, prospective, randomized clinical investigation was to compare the clinical efficacy and safety of sevoflurane and isoflurane during the maintenance of and the recovery from general anaesthesia in elderly patients. METHODS: With the approval of the Ethical Committee and the patient informed consent, 104 ASA physical status II-III patients, aged more than 65 years, were randomized in order to receive either isofluorane (n = 54) or sevoflurane (n = 50) as the main general anaesthetic. After an oral diazepam (0.1-0.2 mg kg-1) and intramuscular atropine (0.007-0.01 mg kg-1) premedication, anaesthesia was induced intravenously and then maintained by adjusting the end-tidal concentrations of the inhalation agent for the maintainance of cardiovascular stability. At the moment of the last skin suture the inhalational agents were discontinued and the neuromuscular block was reversed. The following times were recorded: time of extubation, time of eyes opening, time of command response and readiness for discharge. The occurrence of untoward event throughout the study was also recorded. Before surgery and 24 hr after the procedure, blood was collected in order to assess renal function. RESULTS: No differences in demography, duration of surgery, exposure to the volatile anaesthetic, and renal function laboratory values were observed between the two groups. The time of extubation (median: 8 min versus 11 min, p < 0.01), emergence (median: 8.5 min versus 12.5 min, p < 0.01), command response (median: 10 min versus 15.5 min, p < 0.01), and suitability for discharge from the recovery area (median: 21 min versus 27.5 min, p < 0.01) were shorter in the sevoflurane group than in the isoflurane one. The success rate (absence of any event) during induction and maintenance periods was better in sevoflurane than isoflurane group (p < 0.02 and p < 0.001, respectively). Hypotension (systolic arterial blood pressure decrease > 30% of baseline values) was observed in 16 patients receiving isoflurane (29%) and only in 5 patients receiving sevoflurane (10%) (p < 0.02). DISCUSSION: When used in elderly patients undergoing operations of intermediate duration, sevoflurane provides a more rapid emergence from anaesthesia with a faster fulfillment of discharging criteria, and a more stable cardiovascular homeostasis than isoflurane. Renal function also appears to be equally well preserved with both anaesthetics.

[The organizational problems of the hospitals of the Nord Italia Transplant Program (NITp) engaged in the activities of organ retrieval for transplantation. The Collaborative Group of Resuscitation Anesthetists]. / Problemi organizzativi degli Ospedali del Nord Italia Transplant (NITp) impegnati nell'attività di reperimento di organi a scopo di trapianto. Il Gruppo Collaborativo degli Anestesisti Rianimatori.

If the quality of results of organ transplantation in NITp is highly satisfactory, the same cannot be said for the number of transplants performed, which only cover 20-25% of the requirement. To understand the causes of organ shortage, a study group of Anaesthesiologists and Transplant Coordinators from the North Italy Transplant Program (NITp) investigated, through a questionnaire addressed to the Heads of 103 Intensive Care Units (ICU) in 92 Hospitals in the NITp area, some of the organizational problems linked to donor identification and treatment and to organ retrieval. The questionnaire took into consideration the number of possible donors identified in 1990, those retrieved and the causes for non retrieving organs and examined a number of variables linked both to retrieval and to ICUs and Hospitals organization. The results show that potential donors were 461: 143 (31%) were used, 138 (30%) were lost due to family opposition to organ donation, 192 (20%) for clinical reasons and 88 (19%) for organizational reasons. The latter figure represents 5% of non retrieval in the most active ICUs and increases to 50% in the Hospitals that had procured no donors in 1990. The main obstacles for ICUs to procure organ donors are: convey the Medical-Legal Committee, carry out of complicated administrative procedures, availability of round the clock specialized equipment for neurological assessment (especially for ICU outside Neurosurgical and Neurological departments), inadequate number of medical and nursing staff, most of all at night, and finally the difficulty in the management of non-traumatic cerebrovascular patients.