The increasing use of ambulatory surgery requires methods of anaesthesia that allow patients to be discharged soon after the operation is completed. Spinal anaesthesia is usually simple and quick, and the incidence of post-spinal headache has been reduced by using non-cutting small-gauge needles. Limiting the spread of spinal anaesthesia, as long as it still provides analgesia for surgery, should reduce the haemodynamic effects and speed recovery. Restricted spinal anaesthesia, intended to be unilateral using 0.18% hypobaric bupivacaine via a 25G or 27G Whitacre unidirectional needle, was compared with epidural anaesthesia (using a mixture of lignocaine and prilocaine) in 64 matched-pair patients undergoing ambulatory arthroscopy. Motor blockade, assessed for the specific myotomes L2 to S1, was significantly more unilateral in the spinal group. Two patients in the spinal group and nine patients in the epidural group were treated for hypotension (P < 0.05). One patient in the spinal group developed a post-spinal headache. One patient in the epidural group rated the anaesthesia poor.

In an attempt to attenuate the cardiovascular pressor response to laryngoscopy and intubation, 30 patients presenting for routine ophthalmic surgery were studied and were randomly allocated into two groups: group A (n=15) received direct laryngeal/tracheal lignocaine spray immediately before intubation; and group B (n=15) received orolaryngeal lignocaine spray before the induction of anaesthesia. In both groups, general anaesthesia was induced with thiopentone 3–5 mg kg−1, followed by atracurium 0.6 mg kg−1 to facilitate tracheal intubation. Laryngoscopy and endotracheal intubation caused a significant increase in heart rate, by 28% in group A and 23% in group B (P<0.05 in both), and in diastolic blood pressure, by 28% in group A and 24% in group B (P<0.05 in both). In group A, the systolic blood pressure also increased significantly (by 18%) after intubation, but there was no significant change in group B. In addition, the plasma lignocaine concentrations remained well below the toxic range in both groups. It was concluded that topical lignocaine administration as an orolaryngeal spray before the induction of anaesthesia is effective in reducing but not abolishing the pressor response to laryngoscopy and endotracheal intubation

The value of pulmonary artery catheterization is a matter for discussion. Previous studies suggest that direct measurements of intravascular volume distribution and cardiac volume indices may be of greater relevance than central venous and pulmonary capillary wedge pressure. We therefore used a thermo-dye dilution technique for the quantification of central blood volume, right ventricular end-diastolic volume and left heart volume in patients undergoing coronary artery bypass surgery. Measurements were performed after the induction of anaesthesia as well as 1, 6 and 24 h after surgery. Central venous pressure was significantly increased at 1 and 6 h, whereas right ventricular end-diastolic volume was increased only at 6 h post-operatively. Pulmonary capillary wedge pressure showed a tendency to increase whereas left heart and central blood volume decreased significantly after surgery. The results of the present study suggest that changes in cardiac filling pressure do not indicate changes in indices of cardiac volume in patients after coronary bypass surgery.

This double-blind, randomized trial compared the onset of sedation with two patient-controlled sedation regimens, allowing a maximum of 16 or 25 mg min−1 propofol. Forty fit young patients presenting for elective surgery were asked to try to put themselves to sleep using the system. Onset times of sedative effect, slurred speech and amnesia were recorded. All patients achieved satisfactory sedation, and none became oversedated. Patients receiving 16 mg min−1 propofol were not reliably sedated within 5 min and took significantly longer to develop slurred speech and amnesia (P< 0.01 for both). We conclude that this maximum infusion rate does not produce amnesia or sedation rapidly enough to be clinically useful. A maximum infusion rate of 25 mg min−1 allowed rapid sedation in all patients without oversedation and may be an acceptable compromise between efficacy and safety.

Gamma-hydroxybutyrate (GHB) may well be developed as an alternative for optional sedation during spinal anaesthesia. As in the case of propofol (PRO), GHB has good sedative properties associated with cardiovascular and respiratory stability. When used as a narcotic agent, recovery times are variable (e.g. > 30 min); in contrast, sedative dosages, as used in intensive care patients (e.g. 10–20 mg kg−1 h−1), result in adequate clinical recovery. The goal of the present study was to compare the clinical properties of GHB and PRO after continuous administration during spinal anaesthesia (SPA). Thirty patients (ASA I and II) received either GHB (n=15) or PRO (n=15) at random. Patients refusing sedation (n=15) received 0.9% saline (control). At eight defined time points, haemodynamic (BP, HR), respiratory (RR, RMV, Pao2, Spo2, Peto2, Petco2, ̇Vo2, ̇Vco2) and endocrinological parameters (plasma concentrations of noradrenaline and adrenaline) as well as the clinical side-effects were assessed simultaneously. With both sedatives, the desired level of sedation was achieved. Recovery times ranged between 1.7±0.9 min with PRO and 6.1±4.9 min with GHB. GHB provided stable haemodynamic conditions without clinically relevant respiratory depression. In contrast, PRO caused a decrease in mean arterial pressue (MAP) of 15%, whereas respiratory minute volume was decreased by 53% (with periods of apnoea, Spo2<90%). ̇Vo2 and ̇Vco2 correlated with respiratory minute volume (GHB, PRO, control). Plasma noradrenaline and adrenaline concentrations remained nearly constant in the GHB and control groups and declined during sedation with PRO. Both GHB and PRO are suitable for optional sedation during spinal anaesthesia. Control and recovery are acceptable for clinical purposes. It seems that GHB and PRO have similar haemodynamic, respiratory and endocrinological characteristics. Therefore, GHB may serve as an alternative for the established management of continuous sedation during SPA with PRO.

One may have to use a monitor of cortical suppression to maintain the optimal level of sedation and hypnosis. The bispectral index (BIS), a processed EEG parameter, which incorporates coupling along with the frequency and amplitude of EEG waveforms, has been proposed as a measure of the pharmacodynamic anaesthetic effect on the central nervous system. The numerical value of BIS varies from 0 to 100 (no cerebral activity to fully awake patient). In order to achieve the desired level of propofol sedation or hypnosis, a target concentration of propofol at the effect site or in the blood must be delivered. Alternately, one may use BIS monitoring to monitor hypnosis or sedation levels or to reflect propofol concentrations in the blood. Significant correlations between plasma propofol concentrations and BIS values (r=0.68–0.78) have been reported by many investigators. During propofol-induced sedation, BIS values may be maintained above 75 to prevent airway obstruction and hypoxia. During propofol intravenous anaesthesia, BIS values from 40 to 60 have been proposed to maintain the desired level of hypnosis, with values below 50 associated with an insignificant probability of recall. However, the major limitation of the BIS monitor (monitor of hypnosis) relates to the fact that balanced anaesthesia comprises hypnosis, areflexia and analgesia and requires the administration of hypnotic agents, muscle relaxants and analgesics to achieve the desired clinical effects. Therefore, besides using the BIS value guidelines, one may also consider the haemodynamic, autonomic and somatic responses of the patient, the anaesthetic technique and the surgical interventions before deriving definite conclusions about the overall anaesthetic state of the patient.

Sixteen patients suffering from rheumatoid or osteoarthritis of the shoulder joint were studied. All patients complained of pain and limitation of active movement of the shoulder joint. Combined neural blockade of the suprascapular nerve (SSNB) and articular branches of the circumflex nerve (ACNB) was carried out using 4 mL of 1% prilocaine and 4 mL of 6% aqueous phenol. Following this procedure, the mean value for pain intensity decreased by 69% (VASP 2.7) and for abduction, adduction and flexion increased by 36–67% over a mean time of 13 weeks. Functional external and internal rotation of the shoulder joint also increased after neural blockade. These findings were significant (P<0.05). Further clinical evaluation of combined SSNB and ACNB in relation to previously reported methods of neural blockade of the shoulder joint is warranted using a randomized, controlled, comparative study. Conventional power calculations (80% power, 5% test) indicate that 17 patients per group would be necessary to detect one standard deviation (about 2 VASP) or 64 per group to detect a change of 0.5 standard deviations.

In a prospective randomized study in children, we compared caudal bupivacaine–clonidine with bupivacaine–morphine to evaluate whether clonidine can be used as an alternative to morphine in caudal anaesthesia. Caudal anaesthesia was administered in 36 children undergoing orchidopexy, hernia repair or circumcision, using 1.5 mL kg−1 bupivacaine 0.18% with either 1 μg kg−1 clonidine (group 1) or 30 μg kg−1 morphine (group 2). Haemodynamic and respiratory parameters, anaesthetic requirements, recovery time and pain score were monitored for 24 h. Eleven children in group 1 and nine children in group 2 did not need any supplementary systemic analgesics throughout the 24-h observation period. Mean (±SD) duration of analgesia in the remaining patients was 6.3 h (±3.3 h) in group 1 and 7.1 h (±3.4 h) in group 2 (P=0.43). Recovery time after anaesthesia was significantly longer in group 1 (16.6±8.8 min) than in group 2 (11.5±4.7 min) (P< 0.05). We conclude that analgesia provided by 1 μg kg−1 clonidine added to caudal bupivacaine is comparable with that provided by 30 μg kg−1 caudal morphine with bupivacaine. Clonidine at this low dose did not cause respiratory depression.

Hypnotic endpoints and/or EEG variables, e.g. bispectral index, 95% spectral edge frequency and median frequency, have been studied to monitor anaesthetic (hypnotic) depth during total intravenous anaesthesia. In this study, the relation between the hypnotic endpoints of unresponsiveness to verbal commands, loss of eyelash reflex and body movement response to mechanical nasal membrane stimulation vs. bispectral index, 95% spectral edge frequency and median frequency during propofol anaesthesia with or without fentanyl is presented. Forty-two patients were randomly assigned to receive either propofol infusion, 30 mg kg−1 h−1 (n=22), or propofol infusion, 30 mg kg−1 h−1+fentanyl bolus, 2 μg kg−1 i.v. (n=20). Bispectral index, 95% spectral edge frequency and median frequency and propofol doses were monitored and recorded at unresponsiveness to verbal commands, loss of eyelash reflex and inhibition of nasal body movement response. The bispectral index values were significantly higher in the propofol+fentanyl compared with the propofol group, i.e. 74.7±10.9, 73.1±10.5 and 47.1±9.2 vs. 65.8±9.8, 59.6±10 and 33.8±5.7 at unresponsiveness to verbal commands, loss of eyelash reflex and inhibition of nasal body movement response respectively. Doses of propofol for achieving the hypnotic endpoints were significantly lower in the propofol+fentanyl compared with the propofol group. Plasma propofol concentrations at inhibition of nasal body movement response were lower in the propofol+fentanyl compared with the propofol group (9.2±2.0 μg mL−1 vs. 14.1± 4.2 μg mL−1). Our results suggest that fentanyl pretreatment potentiates the effects of propofol and achieves the hypnotic endpoints at higher bispectral index values and lower propofol doses and concentrations (measured at inhibition of nasal body movement response).

Oxygen consumption (̇Vo2) measured by indirect calorimetry (Nellcor-Puritan-Bennett 7250; Carlsbad, CA, USA) has been compared with ̇Vo2 calculated by the Fick method in 22 volume-controlled ventilated general surgical patients in the early post-operative period. For 198 pairs of measurements, ̇Vo2 Fick and ̇Vo2 indirect calorimetry correlated significantly (y=1.00x–35.8, P=0.0001, r=0.77). ̇Vo2 indirect calorimetry was 212±32 mL min−1 and ̇Vo2 Fick was 177±41 mL min−1 (P=0.0001). The bias was 35±26 mL min−1. This difference represents 16±13% of the total body ̇Vo2. ̇Vo2 calculated by the Fick method did not accurately predict ̇Vo2 measured by indirect calorimetry, and the two methods were not interchangeable. ̇Vo2 calculated by the Fick method underestimated ̇Vo2 as measured by indirect calorimetry by a systematic quantity that could be attributed, in part, to ̇Vo2 of the lung. Indirect calorimetry should be the preferred method for measuring total body ̇Vo2 in mechanically ventilated surgical patients.

This study was undertaken to determine the minimum effective dose of granisetron, 5-hydroxytryptamine type 3 receptor antagonist, for the prevention of post-operative vomiting in children undergoing general inhalational anaesthesia for surgery (inguinal hernia and phimosis). In a randomized, double-blind manner, 120 children, ASA physical status I, aged 4–10 years, were assigned to receive placebo (saline) or granisetron at three different doses (20 μg kg−1, 40 μg kg−1, 100 μg kg−1) intravenously immediately after inhalation induction of anaesthesia (n=30 of each). A complete response, defined as no emesis and no need for another rescue antiemetic during the first 24 h after anaesthesia, occurred in 57% with placebo, 67% with granisetron 20 μg kg−1, 90% with granisetron 40 μg kg−1 and 90% with granisetron 100 μg kg−1 respectively (P<0.05; overall Fisher's exact probability test). No clinically important adverse events were observed in any of the groups. Our results suggest that granisetron 40 μg kg−1 is the minimum effective dose for the prevention of emesis after paediatric surgery, and that increasing its dose to 100 μg kg−1 provides no demonstrable benefit.

Patients treated with bleomycin (BLM) are at risk of developing acute respiratory distress syndrome (ARDS) post-operatively, and this has been associated with high intraoperative concentrations of oxygen. We report progressive arterial desaturation noticeable 2 h after the start of a 4-h radical neck dissection for which the anaesthesia included 50% O2 in N2O. The patient had received two courses of bleomycin within the previous 2 months and had undergone an uneventful right hemiglossectomy under shorter but otherwise similar anaesthesia 4 weeks previously. His pulmonary function tests before the second procedure showed a slight depression of diffusing capacity (DLco) to 80% of predicted and minimal airway obstruction consistent with his history of smoking. The pulse oximetric reading during his second procedure reached 75%, but rose to 95% after treatment with methylprednisolone, salbutamol and inspired O2 concentrations between 80% and 100%. By the end of the procedure, he satisfied the criteria for ARDS and was transferred to the ICU, where he developed bilateral pneumonia, deteriorated and died of multiple organ failure. This case suggests that the risk of hyperoxic pulmonary damage in patients exposed to bleomycin may increase not only with the degree and duration of hyperoxia in a given exposure, but also with the latent effects of recent previous exposure. Near normality of pulmonary function tests cannot be taken as reassurance, and small changes may have more adverse prognostic significance than in patients who have not been exposed to bleomycin.

Complication during a drum catheter placement via an antecubital fossa vein is presented.