Twenty-three patients undergoing elective coronary artery bypass graft surgery with moderate hypothermic bypass, under opiate-benzodiazepine anaesthesia were investigated during the first 7 h following surgery. Patients with recent myocardial infarct (< 6 weeks), reduced left ventricular ejection fraction (< 40%) or requiring inotropic support were excluded. During the first 3 h after surgery, higher oxygen uptake and oxygen extraction ratio were found in shivering patients (n = 5) compared with non-shivering patients (n = 16). A significant relation was found between oxygen uptake and the oxygen extraction ratio for the pooled data (R = 0.80 and 0.87, in shivering and non-shivering patients, respectively) as well as for the individual patients. A weaker relation was observed between cardiac output and oxygen uptake. The lack of adequate circulatory compensation could be related to the depressant effects of residual anaesthesia on the myocardium, surgical trauma, cardioplegic arrest and to peripheral vasoconstriction.

Sufentanil or a sufentanil-clonidine combination was evaluated to determine whether the basal rate in patient-controlled epidural analgesia (PCEA) might affect the daily consumption, quality of analgesia or incidence of side effects. Following Caesarean section delivery, 60 patients were randomly assigned to receive one of the four following PCA regimens (15 patients per group) for the relief of post-operative pain by the epidural route: sufentanil 2μg mL−1 in 0.9% NaCl, demand dose 5μg i.e. 2.5mL, (group S+ with, group S without an infusion at 2.5mL hr−1) or sufentanil 2μg mL−1 + clonidine 3μg mL−1, demand dose 5μg sufentanil + 7.5μg clonidine i.e. 2.5mL (group SC+ with and SC without an infusion of 2.5ml hr−1). The other PCA settings (Bard I PCA pump) were a lock out interval of 10 min and a 1h limit of 20μg sufentanil and 30μg clonidine i.e. 10mL. The parameters measured were the analgesic drug consumption and number of dose demands during the first 24h, pain scores at 6h intervals, side effects and quality of sleep. The concurrent infusion increased the dose requirements regardless of the content of the syringe. Consumption of sufentanil was the highest in those patients receiving the plain solution with a basal infusion. Clonidine addition reduced the dose requirements but only significantly in those receiving the background infusion. Patients treated with the mixture tended to reach lower pain scores than those receiving sufentanil only without basal rate. Patients receiving the mixture with basal rate requested significantly fewer additional demands compared with the three other groups, but this did not influence the quality of sleep. Since side effects were more frequently registered in the patients in this group, it was concluded that the optimum regimen was the sufentanil-clonidine combination but with deletion of the basal rate.

In order to assess if a mixture of phenylephrine/lignocaine is as effective as cocaine for local analgesia and vasoconstriction during nasal fibreoptic intubation, 99 patients receiving topical nasal analgesia either with cocaine 10% or a mixture of phenylephrine 1% and lignocaine 4% were studied in a randomized double-blind investigation. After topical analgesia a flexible fibreoptic endoscope was advanced through a nostril. Larynx, glottis and trachea were endoscopically sprayed with lignocaine. Following induction of anaesthesia a nasotracheal tube was inserted fibreoptically. Pain intensity and amount of epistaxis during endoscopy were assessed.Blood pressure, heart rate and ECG-ST segment were determined before and after topical nasal analgesia, after induction of anaesthesia and after nasotracheal intubation. There were no significant differences in painintensity or epistaxis between groups during endoscopy, nor significant alterations in haemodynamic parameters or ST-segment. It is concluded that the mixture of phenylephrine and lignocaine is a useful alternative to cocaine for local analgesia and vasoconstriction during nasal fibreoptic intubation.

The effects of different anaesthetics on the neutrophil oxidative response in vitro are compared. Neutrophils were stimulated with small amounts of the bacterial peptide N-formyl-L-methionyl-L-leucyl-phenylalanine as a physiological, receptor-dependent stimulus. A new flow cytometry-based method capable of detecting the small amounts of H2O2 generated by neutrophils in a heterogenous all-or-none response following submaximal stimulation with N-formyl-L-methionyl-L-leucyl-phenylalanine was used. Propofol and thiopentone suppressed the respiratory burst significantly (P < 0.05 and P < 0.01) in therapeutic concentrations, while midazolam and methohexitone inhibited significantly (P < 0.01) only at concentrations greater than the therapeutic range. Impairment of the neutrophil response was primarily because of a reduction in the number of neutrophils participating in the respiratory burst and not of a proportional decrease of the fluorescence of all neutrophils.

Intrathecal midazolam for use as a post-operative analgesic when given alone and in conjunction with intrathecal diamorphine was assessed. Fifty-two patients scheduled for elective Caesarean section under spinal anaesthesia were randomly allocated to receive either bupivacaine (B), bupivacaine with diamorphine (BD), bupivacaine with midazolam (BM) or all three (BMD) by intrathecal injection. Post-operatively, no differences in visual analogue score (VAS), sedation or post-operative nausea and vomiting (PONV) could be demonstrated between groups. Patient-controlled analgesia system (PCAS) usage was significantly greater in group B when compared with the other groups. Pruritus was commoner in patients receiving diamorphine (BMD & BD). No side effects attributable to midazolam were identified. Intrathecal midazolam at this dose appears safe and has clinically detectable analgesic properties. The duration of useful analgesia appears to be short-lived.

The use of adrenaline added to bupivacaine during epidural analgesia for labour is controversial. The effects of epidural analgesia with bupivacaine containing adrenaline on maternal blood pressure and heart rate, uterine activity, progress of labour, fetal heart rate and Apgar scores, were assessed using visual analogue pain scores, upper level of sensory block and motor blockade in 60 parturients who were allocated randomly to receive: 10 mL of bupivacaine 0.25% plain (group I) or with adrenaline 5 μg mL−1 (group II) or with adrenaline 1.66 μg mL−1 (group III).

The first stage of labour was significantly longer in group II than in group I [414 ± 49 vs. 296 ± 24 min (± SD)]. There were no other significant differences. It is concluded that adrenaline at 5 μg mL−1 significantly prolongs the first stage of labour. Neither adrenaline 5 μg mL−1 nor 1.66 μg mL−1 has any beneficial effect.

The influence of haemodilution with colloids on somatosensory evoked potentials in non-premedicated volunteers is reported. In seven volunteers (randomized crossover design), blood (20 mL kg−1 within 30 min) was removed and simultaneously replaced by gelatin 3% or hydroxyethylstarch 6%. After 30 min, blood was retransfused within 30 min. Median and posterior tibial nerve somatosensory evoked potentials were recorded from the cortex, second cervical vertebra, Erb's point and 1st lumbar vertebra, respectively. One volunteer experienced a severe allergic reaction to gelatin, therefore only six gelatin trials were evaluated. Haemodilution decreased the haematocrit from 39.8 ± 1.6% (mean ± SD) to 31.1 ± 2.0% (gelatin) and from 40.7 ± 1.7% to 29.8 ± 1.5% (hydroxyethylstarch), respectively. Retransfusion increased haematocrit to 34.4 ± 0.9% (gelatin) and to 34.2 ± 1.3% (hydroxyethylstarch). Neither haemodilution with gelatin nor haemodilution with hydroxyethylstarch or retransfusion influenced evoked potentials. In conclusion, the treatment of blood loss up to 30% of estimated blood volume with gelatin or hydroxyethylstarch will not affect somatosensory evoked potential monitoring provided normovolaemic conditions are maintained.

Ketamine 3–6 mg kg−1 given by mouth to paediatric patients for anaesthetic premedication was evaluated. Forty-three children, ages 2–9 years were randomly allocated to receive either ketamine (3 or 6mg kg−1) or placebo (cola 0.2 mL kg−1). Oral use of ketamine made separation from the families easier, gave an increased level of sedation, made acceptance of mask application easier and improved the emotional state in the recovery phase. These improvements were present with ketamine 3mg kg−1 and 6mg kg−1 in comparison with the placebo. We conclude that 3mg kg−1 ketamine given by mouth to premedicate paediatric patients is as effective as 6mg kg−1 but has a decreased incidence of side effects such as nystagmus and vomiting.

The facial nerve is monitored intra-operatively using electromyography to identify and prevent damage during the excision of an acoustic neurinoma. In order to determine whether a profound level of peripheral neuromuscular blockade could be achieved without compromising facial electromyographic monitoring, 11 patients undergoing resection of acoustic neuroinoma were studied. After induction of anaesthesia, an infusion of atracurium was administered to reduce the integrated electrically evoked muscle potential (EEMP) of the hypothenar eminence by 70–100%. The facial nerve was directly stimulated in the surgical field and the facial evoked muscle potentials (EMPs) were recorded. Even under complete peripheral neuromuscular blockade (i.e. no electrically evoked muscle potential measurable over the hypothenar eminence, no palpable hypothenar muscle response) it was possible to evoke facial muscle electromyographic responses by stimulation of the facial nerve.

The changes in heart rate and arterial blood pressure following the administration of suxamethonium in healthy children (mean age 3.8 ± 0.3 years) during inhalational induction with either sevoflurane (n = 22) or halothane (n = 19) were studied. Heart rate 60 s following suxamethonium administration increased significantly in the sevoflurane but not in the halothane group. In the halothane group, four children required intravenous (i.v.) atropine as a result of bradycardia. None of the children in the sevoflurane group developed bradycardia following suxamethonium (P < 0.05). Values of oxygenation, ventilation and age corrected minimal alveolar concentration were comparable at all measurement times. The haemodynamic response to the administration of suxamethonium in children anaesthetized with sevoflurane seems to reflect the stimulation of the autonomic ganglia by suxamethonium whereas this positive chronotropic effect is attenuated or reversed by halothane.

There has been controversy over whether forward blood flow during closed-chest cardiopulmonary resuscitation (CPR) is generated by a general increase in intrathoracic pressure (chest-pump theory) or by creating atrioventricular gradients that close the mitral valve and open the aortic valve during thoracic compression (cardiac pump theory). The crucial issue is the position of the mitral valve during the downstroke of chest movement. Questions remain over the actual mechanics of mitral and aortic valve function. This report describes an intraoperative cardiac arrest followed by CPR during which routinely instituted two-dimensional transoesophageal Doppler echocardiography enabled study of the motion of the valves of the left heart and the transmitral blood flow.