The most suitable time for tracheal intubation, following vecuronium 0.1 mg kg−1, was estimated in 120 patients. The trachea was intubated at cessation of the visually observed response of the orbicularis oculi muscle to facial nerve stimulation (group 1; n = 30), or of the manually detected response of the adductor pollicis to ulnar nerve stimulation (group 2; n = 30), or after waiting 3 min (group 3; n = 30), or 4 min (group 4; n = 30). There were no significant differences in intubation scores between the four groups of patients. Loss of response to train-of-four stimulation occurred significantly sooner in group 1 (orbicularis oculi) than in group 2 (adductor pollicis) P = 0.021). However, intubating conditions were poor in four patients (14%) in group 1, compared with none in group 2 and one in groups 3 and 4, respectively. Thus, contrary to expectations, the cessation of the response of the orbicularis oculi muscle did not guarantee good or even satisfactory intubating conditions. The results suggest that in fit adult patients it is as good to wait 3 min after injection of vecuronium 0.1 mg kg−1 before tracheal intubation, as to use a nerve stimulator.

Background and objective: Although combined spinal and epidural anaesthesia is efficient and easy to perform, the technique can be a double-edged sword having the potential risk that an increased flux of drugs across the meninges through the hole made in it may lead to severe adverse effects. The aim was to compare the incidence of adverse events when an epidural injection of morphine was given after combined spinal and epidural anaesthesia or after epidural anaesthesia.

Methods: Fifteen patients had an epidural catheter inserted at the L2–3 interspace, and then a spinal block administered via the L3–4 interspace. Another 15 patients only had an epidural catheter inserted. After the onset of spinal or epidural anaesthesia had been confirmed, morphine 2 mg was injected into the epidural space, and a continuous epidural infusion of morphine was started. At the end of the operation and at 4, 8 and 12 h after the administration of epidural morphine and on the next day, the following variables were examined: blood pressure, heart rate, respiratory rate, arterial blood-gas analysis, visual analogue scale pain scores, nausea/ vomiting scores, and pruritus scores.

Results: In the study population, the epidural injection of morphine was not associated with a significantly higher incidence of adverse events when given after spinal anaesthesia than after epidural anaesthesia.

Conclusions: The adverse effects associated with epidural morphine given after spinal anaesthesia did not increase significantly when a 27-G Whitacre needle was used. Thus, the morphine flux through the meningeal hole into the cerebrospinal fluid was trivial.

Dedicated nitric oxide equipped ventilators are now available commercially but are not yet common in clinical practice. With other ventilators, there is no standardized procedure for the administration or monitoring of nitric oxide. Wedescribe the use of nitric oxide in conjunction with a simple time–cycled, pressure regulated, flow generating ventilator attached to a model infant–sized lung. The measured nitric oxide concentrations were always less than calculated. Infusion site, minute ventilation and sampling port all affected nitric oxide concentration (P<0.05). Increasing minute ventilation lowered measured nitric oxide concentration exponentially. Mixing of gases improved when nitric oxide was infused closer to the ventilator. Acid contamination was found in water samples from humidifier, water trap and ventilator gas outlet. Acidification was reduced, without change in measured nitric oxide delivery, when infused prehumidifier. We recommend, when used as therapy, nitric oxide levels in inspired gases should always be measured.

Summary

Background and objective: The study was designed to identify those factors associated with early tracheal extubation following cardiac surgery. Previous studies have tended to concentrate on surgery for coronary artery bypass or on other selected cohorts.

Methods: Sequential cohort analysis of 296 unselected adult cardiac surgery patients was performed over 3 months.

Results: In total, 39% of all patients were extubated within 6 h, 89% within 24 h and 95% within 48 h. Delayed extubation (>6 h after surgery) appeared unrelated to age, gender, body mass index, a previous pattern of angina or myocardial infarction, diabetes, preoperative atrial fibrillation, and preoperative cardiovascular assessment, as well as other factors. Delayed tracheal extubation was associated with poor left ventricular, renal and pulmonary function, a high Euroscore, as well as the type, duration and urgency of surgery. Early extubation (<6 h) was not associated with a reduced length of stay in either the intensive care unit or in hospital compared with patients who were extubated between 6 and 24 h. In these groups, it is presumed that organizational and not clinical factors appear to be responsible for a delay in discharge from intensive care. Patients who were extubated after 24 h had a longer duration of hospital stay and a greater incidence of postoperative complications. Postoperative complications were not adversely affected by early tracheal extubation.

Conclusions: In an unselected sequential cohort, both patient- and surgery-specific factors may be influential in determining the duration of postoperative ventilation of the lungs following cardiac surgery. In view of the changing nature of the surgical population, regular re-evaluation is useful in reassessing performance.

The use of a newly developed aid to jet ventilation of the lungs, a modified Ben-Jet tube (The Hunsaker Monjet tube), is described in a patient with partial upper airway obstruction. This report highlights an unusual use of this device. The Monjet is a fluoroplastic, monitored, self-centring, fine bore tube that can be inserted from the mouth through to the subglottic region. It was originally developed to anaesthetize healthy patients without airway obstruction who were undergoing suspension microlaryngoscopy.

Summary

Background and objective: We investigated whether a high bolus dose of cisatracurium (8× ED95) given at induction can provide muscle relaxation for the major part of a cardiac procedure with hypothermic cardiopulmonary bypass, avoid important postoperative residual curarization and cause no waste of product.

Methods: Twenty patients were randomly assigned either to Group 1 (n = 10) or Group 2 (n = 10). Those in Group 1 were given cisatracurium in a high bolus dose (0.4 mg kg−1). Those in Group 2 received cisatracurium 0.1mg kg−1 at induction followed after 30 min by a continuous infusion of cisatracurium. As an escape medication in case of patient movement, a bolus dose of cisatracurium 0.03 mg kg−1 was given.

Results: In Group 1 (large cisatracurium bolus dose), the clinical duration of effect (until T1/T0 = 25%) was 110 min. Six of 10 patients in Group 1 required additional boluses of cisatracurium intraoperatively. Four of these six had received an additional bolus near the end of surgery and had a train-of-four (TOF) ratio = 0 at the end. The other four patients in Group 1 had a final TOF ratio >0.9. In Group 2 (continuous cisatracurium infusion), only two patients had a TOF ratio >0.9 at the end of surgery, no patient moved and none received additional boluses. The total amount of cisatracurium used in the bolus and infusion Groups was 34.5 ± 7.8 and 21.3 ± 5.7 mg, respectively (P = 0.0004).

Conclusions: For continued neuromuscular block during hypothermic cardiac surgery, a high bolus dose of cisatracurium appears to be safe, although it is not an alternative to a continuous infusion, as its neuromuscular blockade does not cover the intraoperative period and a high incidence of movements occurs. In the patients who received a high bolus dose of cisatracurium, postoperative residual curarization appeared after additional boluses had been given. The consumption of cisatracurium by high bolus was significantly greater than with continuous infusion.

The case of a 64-year-old man who was admitted to hospital with fever, general deterioration and anorexia is reported. For the past 4 years, the patient had been receiving corticosteroid therapy for a chronic inflammatory demyelinating polyradiculoneuropathy. Soon after admission the patient developed respiratory insufficiency as a result of a massive pneumonitis, with severe hypoxia, acute anaemia, acute renal failure and a systemic inflammatory response syndrome (SIRS) requiring admission to the Intensive Care Unit (ICU). All faecal, bronchial, duodenal and urine samples showed Strongyloides stercoralis larvae. Despite antihelmintic therapy and cardiorespiratory support, the patient died from the consequences of irreversible shock. Strongyloidiasis is present worldwide and can be a chronic, essentially asymptomatic infection. This nematode can produce an overwhelming hyperinfection syndrome, especially in patients showing deficient cell-mediated immunity. Strongyloides hyperinfection syndrome is frequently fatal but is potentially a treatable clinical condition. Patients undergoing immunosuppressive therapy or with suspected immunity deficiency (HIV infection, malnutrition, lymphomas, leukaemias or other neoplasia treated with systemic radiotherapy or chemotherapy) must be also monitored for opportunistic Strongyloides stercoralis infection, because clinical manifestation of the systemic hyperinfection syndrome can be rather non-specific.

Summary

Background and objective: This prospective, randomized, controlled study evaluated the effects on oxygenation by applying a selective and patient-specific value of positive end-expiratory pressure (PEEP) to the dependent lung during one-lung ventilation.

Methods: Fifty patients undergoing thoracic surgery under combined epidural/general anaesthesia were randomly allocated to receive zero PEEP (Group ZEEP, n = 22), or the preventive application of PEEP, optimized on the best thoracopulmonary compliance (Group PEEP, n = 28). Patients' lungs were mechanically ventilated with the same setting during two- and one-lung ventilation (FiO2 = 0.5; VT = 9 mL kg−1, inspiratory : expiratory time = 1 : 1, inspiratory pause = 10%).

Results: Lung-chest wall compliance decreased in both groups during one-lung ventilation, but patients of Group PEEP had 10% higher values than patients with no end-expiratory pressure (ZEEP) applied – Group ZEEP (P < 0.05). During closed chest one-lung ventilation, the PaO2 : FiO2 ratio was lower in Group PEEP (232 ± 88) than in Group ZEEP (339 ± 97) (P < 0.05); but no further differences were reported throughout the study. No differences were reported between the two groups in the need for 100% oxygen ventilation (10 patients of Group ZEEP (45%) and 14 patients of Group PEEP (50%) (P = 0.78)) or re-inflation of the operated lung during surgery (two patients of Group ZEEP (9%) and three patients of Group PEEP (10%) (P = 0.78)). Postanaesthesia care unit discharge required 48 min (25th–75th percentiles: 32–58 min) in Group PEEP and 45 min (30–57 min) in Group ZEEP (P = 0.60).

Conclusions: The selective application of PEEP to the dependent, non-operated lung increases the lung–chest wall compliance during one-lung ventilation, but does not improve patient oxygenation.

Summary

Background and objective: Intrathecal ketamine as the sole anaesthetic agent has demonstrated a lack of cardiovascular depression that should be of advantage in an elderly population. S(+) ketamine has three-times the analgesic potency of R(−) ketamine and its antinociceptive effects after intrathecal administration in rats are known. We decided to evaluate the effects of intrathecal S(+) ketamine added to a small dose of spinal bupivacaine in elderly patients undergoing transurethral prostate surgery.

Methods: Forty males over 60 yr old, scheduled for transurethral prostate resection under spinal anaesthesia, were studied in a prospective, double-blinded, randomized way. Patients were allocated to receive either bupivacaine 10 mg or bupivacaine 7.5 mg combined with S(+) ketamine 0.1 mg kg−1. Spinal block onset time, maximum sensory level, duration of blockade, haemodynamic variables, postoperative analgesic requirements and adverse events were recorded.

Results: Onset times of motor and sensory block were shorter in the bupivacaine plus S(+) ketamine group. Incomplete motor block of the lower extremities was seen in 80% of the patients in bupivacaine plus S(+) ketamine group. Duration of complete motor block and spinal analgesia was shorter in the bupivacaine plus S(+) ketamine group. There was no significant difference in arterial pressure. Heart rate decreased after spinal anaesthesia in the bupivacaine plus S(+) ketamine group and was significantly lower until the end of anaesthesia. The incidence of adverse effects was not different between groups.

Conclusions: Intrathecal S(+) ketamine administered with a low dose of bupivacaine provides shorter motor and sensory block onset time, shorter duration of action and less motor blockade in elderly males.

Background and objective: The aim was to examine the course of intraocular pressure after relaxation with different doses of cisatracurium.

Methods: The investigation was carried out as a prospective, randomized double-blind study in a crossover design in 30 postoperative patients with stable haemodynamic and respiratory function (ASA I and II). To exclude any disrupting factors, patients remained intubated and continuously sedated. Twenty patients received an intubation dose (2 × ED95) of cisatracurium (0.1 mg kg−1) compared with atracurium (0.5 mg kg−1). In a second series, 10 patients were given an effective dose, ED95 (0.05 mg kg−1), and a repeat dose (0.02 mg kg−1) of cisatracurium. The intraocular pressure was determined before (T0) as well as 1 (T1), 5 (T5), 10 (T10), 15 (T15), 20 (T20) and 45 (T45) min after bolus administration.

Results: Intraocular pressure decreased after an intubation dose of either cisatracurium or atracurium, and reached a minimum after 10 min (6.7 ± 2.2 and 7.9 ± 2.1 mmHg, respectively). There was no significant difference between either muscle relaxant (P = 0.27). When lower doses of cisatracurium (0.05 and 0.02 mg kg−1) were applied, the intraocular pressure also decreased, albeit to a lesser extent and with a delayed onset (8.4 ± 1.9 mmHg after 10 min, 9.9 ± 3.4 mmHg after 15 min). There was no significant difference between dosages (P = 0.44).

Conclusions: Cisatracurium is a useful drug in patients when a decrease of intraocular pressure is wanted and where muscle relaxation is necessary and acceptable.

Summary

Background and objective: To compare the effects of sevoflurane and desflurane anaesthesia on lipid peroxidation.

Methods: We studied 40 healthy patients undergoing elective laparoscopic cholecystectomy. Patients were randomly allocated to be anaesthetized either with sevoflurane (n = 20) or desflurane (n = 20). Anaesthesia was maintained with inspiratory concentrations of sevoflurane 1–1.5 MAC (n = 20) or desflurane (n = 20). Samples were taken for plasma malondialdehyde and superoxide dismutase assays before induction of anaesthesia, before skin incision and at the end of surgery. Alveolar cell samples were obtained from the lungs using the technique of protective blind bronchoalveolar lavage, after induction of anaesthesia and at the end of surgery for malondialdehyde and superoxide dismutase concentrations.

Results: Plasma malondialdehyde increased more after the administration of desflurane than after sevoflurane: after induction 5.9 ± 0.6 nmol mL−1 for desflurane vs. 3.8 ± 0.5 nmol L−1 for sevoflurane (P < 0.001); at the end of the surgery: 6.7 ± 0.4 nmol mL−1 for desflurane vs. 4.2 ± 0.3 nmol mL−1 for sevoflurane (P < 0.001). There was a small but significant increase in plasma superoxide dismutase concentration after desflurane – from 24.2 ± 1.2 to 24.9 ± 0.9U mL−1 after induction and 25 ± 1U mL−1 at the end of the surgery (P < 0.01) but no increase with sevoflurane. Malondialdehyde concentrations increased significantly in the cells obtained by protective blind bronchoalveolar lavage at the end of surgery in the desflurane group (from 0.3 ± 0.1 to 1.7 ± 0.2 nmol mL−1 (P < 0.001)), but not in the sevoflurane group. There were no significant differences between the two anaesthetics in the amounts of superoxide dismutase in the samples obtained by protective blind bronchoalveolar lavage.

Conclusions: Desflurane may cause more systemic and regional lipid peroxidation than sevoflurane during laparoscopic cholecystectomy in healthy human beings.

Summary

Background and objectives: During partial liquid ventilation perfluorocarbons are instilled into the airways from where they subsequently evaporate via the bronchial system. This process is influenced by multiple factors, such as the vapour pressure of the perfluorocarbons, the instilled volume, intrapulmonary perfluorocarbon distribution, postural positioning and ventilatory settings. In our study we compared the effects of open and closed breathing systems, a heat-and-moisture-exchanger and a sodalime absorber on perfluorocarbon evaporation during partial liquid ventilation. Methods: Isolated rat lungs were suspended from a force transducer. After intratracheal perfluorocarbon instillation (10 mL kg−1) the lungs were either ventilated with an open breathing system (n = 6), a closed breathing system (n = 6), an open breathing system with an integrated heat-and-moisture-exchanger (n = 6), an open breathing system with an integrated sodalime absorber (n = 6), or a closed breathing system with an integrated heat-and-moisture-exchanger and a sodalime absorber (n = 6). Evaporative perfluorocarbon elimination was determined gravimetrically. Results: When compared to the elimination half-life in an open breathing system (1.2 ± 0.07 h), elimination half-life was longer with a closed system (6.4 ± 0.9 h, P < 0.01), a sodalime absorber (5.0 ± 0.6 h, P < 0.01) or a heat-and-moisture-exchanger (4.5 ± 0.8 h, P < 0.01). The combination of all three methods (7.1 ± 0.8 h) showed no significant additional effects (P > 0.05) when compared to a closed system. Conclusions: Evaporative perfluorocarbon loss can be reduced effectively with closed breathing systems, followed by the use of sodalime absorbers and heat-and-moisture-exchangers.