The influence of labetalol on arterial blood gas data, pulmonary haemodynamics and pulmonary shunting.

The arterial oxygen and carbon dioxide tensions, pulmonary and systemic haemodynamics and pulmonary shunting and mechanics were measured during the first 30 min after intravenous labetalol administration. Thirty patients, recovering in the intensive care unit after neurosurgical interventions were randomly divided in 2 groups of 15 patients, receiving either labetalol or placebo. In the labetalol treated group the arterial oxygen tension decreased from 553.6 +/- 16.8 to 529.3 +/- 19.8 mmHg 5 min after the injection of labetalol. A concomitant increase in arterial carbon dioxide tension from 40.1 +/- 1.1 to 45.5 +/- 1.3 mmHg was noticed. Pulmonary vascular resistance decreased from 159.6 +/- 14.7 to 116.7 +/- 11.7 dynes.sec.cm-5 and pulmonary shunting increased from 4.8% +/- 1.4% to 8.1% +/- 2.4% 5 min following injection. All these changes were statistically significant for p less than 0.01. After 30 min all values had returned to their initial level. No changes were registered in the control group. As airway resistance appeared not to be affected by the labetalol administration it may be concluded that the observed changes in blood gas data are most likely due to a transient decrease of the pulmonary vascular resistance with a concomitant increase in pulmonary shunting.

Parathyroidectomy and postoperative hypocalcemia: a retrospective study.

The data of 24 patients, operated for different types of hyperparathyroidism were reviewed in order to evaluate the evolution of calcium levels during the first week following surgery. A correlation with the preoperative values of alkaline phosphatase could be demonstrated. It may be concluded that in the primary affected patients a stay in the ICU, only for hypocalcemia-related problems, is not required. In secondary hyperparathyroidism however, the more spectacular drops of calcium levels and the risk of other vital complications, justify a follow-up in the ICU for at least 48 hours.

Needs for computing facilities in anesthesiology.

The use of computers in the practice of anesthesiology appears to be very promising--therefore the time has come to reflect on ways to utilize the possibilities of computers in this field. The anesthesiologist is faced with an existing "medical information science" and system developments and must now address these questions: How do computers fit in these systems? What is the kind of support and help one can expect from the use of computers? Next one attempts to define the needs for computer support, taking into account the specific working conditions of various anesthesia teams. A description is made of how a system for medical information is automatized--and by way of an example--how such a computer system for anesthesiologists is linked to a larger regional facility. Advantages and disadvantages of such a system are discussed.

Intranasal sufentanil for pre-operative sedation.

Sufentanil, a short-acting and potent narcotic agent, was studied as a premedicant administered by the nasal route. A total dose of 5 micrograms appeared to be too low, while either 10 or 20 micrograms was very effective in producing sedation. Side effects were minor. There appeared to be no differences between nose drops and spray. In a further study, sufentanil nose drops were compared with saline 0.9% in a double-blind fashion. Sedation of rapid onset but of limited duration was observed in the majority of patients who received sufentanil.

[Low-frequency jet ventilation in laryngoscopic surgery]. / Laagfrekwente jetventilatie bij laryngoscopische chirurgie.

The principle and technique of low frequency pre-glottic jet ventilation for direct laryngoscopy are outlined. A discussion on the advantages and contra-indications in relation to other techniques concludes that low frequency pre-glottic jet ventilation has in our experience become the first choice ventilating technique for direct laryngoscopy.

Preglottic low-frequency Venturi jet ventilation in laryngoscopic microsurgery in adults. The influence of inspiratory time and frequency of ventilation.

The influence of inspiratory time and frequency of jet ventilation was investigated in an experimental model of a jet ventilator and a set of artificial lungs. The optimal ventilatory settings, when used in the clinical context, result in safe, adequate ventilation, as was proved by Astrup and intratracheal pressure measurements in 15 patients.

A comparison of the anaesthetic properties of propofol and methohexitone when used as the sole induction agent for thermocoagulation of the gasserian ganglion.

Methohexitone and propofol were compared when used as the sole induction agent for thermocoagulation of the Gasserian ganglion. Sleeping and apnoea times were not significantly different for both drugs, nor were they for the same drug during repetitive inductions. However, the haemodynamic data showed a better stability when propofol was used. Amnesia may be in favour of propofol. There were no significant differences concerning pre- and post-operative side-effects in both groups.

Safety of labetalol-induced controlled hypotension during middle ear microsurgery.

In order to study the influence of labetalol on the peroperative oxygenation during deliberate hypotension, 50 patients undergoing middle ear microsurgery were randomly divided in two groups of 25 patients; one group receiving labetalol to induce hypotension, the other group receiving placebo in a double blind manner. In the group receiving labetalol the arterial oxygen tension (PaO2) decreased significantly 5 minutes after the intravenous bolus injection. Within 30 minutes the PaO2 returned to the starting level. The arterial carbon dioxide tension (PaCO2) increased within 5 minutes and also returned to the initial level after 30 minutes. These changes were absent in the control group. It is concluded that, although labetalol produces a statistically significant change in PaO2 and PaCO2, this finding has only minor clinical implications and so labetalol remains a safe drug to be used for the induction of deliberate hypotension during middle ear microsurgery.