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Notes: The efficacy of thoracic epidural sufentanil 50 μg was compared with lumbar epidural sufentanil 50 μg in 30 patients (n = 15 in each group) undergoing lateral thoracotomy. Sufentanil was administered epidurally after induction of anaesthesia with sufentanil 1 μg.kg-1 and thiopentone 2–5 mg.kg-1 intravenously. Anaesthesia, nitrous oxide 66%, halothane 0.3% and sufentanil 25 μg intravenously were given whenever the systolic arterial blood pressure increased more than 15 mmHg above the pre-operative value and heart rate exceeded 90 beat.min-1 in the absence of hypovolaemia, or when other autonomic or somatic signs were seen. Four patients in the thoracic epidural group and five in the lumbar epidural group needed supplementary sufentanil. Six patients in the thoracic epidural group and three in the lumbar epidural group each had a single hypotensive episode. Lumbar and thoracic epidural sufentanil are equally effective in contributing to intra-operative analgesia for lateral thoracotomy.

Notes: The efficacy of thoracic epidural sufentanil 50 μg was compared with bupivacaine 0.5% with adrenaline 5 μg.ml-1 (dose 40 mg) or saline, in 30 patients (n = 10 in each group) undergoing lateral thoracotomy. Sufentanil, bupivacaine or saline was administered epidurally after induction of anaesthesia with sufentanil 1 μg.kg-1 and thiopentone 2–5 mg.kg-1. Anaesthesia was maintained with nitrous oxide 66% and halothane 0.3%. Supplementary sufentanil 25 μg was given whenever the systolic arterial blood pressure increased more than 15 mmHg above the pre-operative value, whenever heart rate exceeded 90 beat. Min-1 in the absence of hypovolaemia, or when other autonomic or somatic signs occurred. Fewer patients in the epidural sufentanil (n = 4, p 〈 0.005) and bupivacaine (n = 1, p 〈 0.001) groups required supplementary sufentanil compared to the placebo group, in which all patients needed supplementary sufentanil, but there was no statistical difference between the sufentanil and bupivacaine groups. One or more hypotensive episodes occurred in five patients in the sufentanil group, in all patients in the bupivacaine group and in no patient in the placebo group, and the differences were significant (p 〈 0.02).

Notes: From a prospectively defined cohort of patients who underwent either general, regional or combined anaesthesia from 1 January 1995 to 1 January 1997 (n = 869 483), all consecutive patients (n = 811) who died within 24 h or remained unintentionally comatose 24 h after anaesthesia were classified to determine a relationship with anaesthesia. These deaths (n = 119; 15%) were further analysed to identify contributing aspects of the anaesthetic management, other factors and the appropriateness of care. The incidence of 24-h peri-operative death per 10 000 anaesthetics was 8.8 (95% CI 8.2–9.5), of peri-operative coma was 0.5 (0.3–0.6) and of anaesthesia-related death 1.4 (1.1–1.6). Of the 119 anaesthesia-related deaths, 62 (52%) were associated with cardiovascular management, 57 (48%) with other anaesthetic management, 12 (10%) with ventilatory management and 12 (10%) with patient monitoring. Inadequate preparation of the patient contributed to 30 (25%) of the anaesthesia-related deaths. During induction of anaesthesia, choice of anaesthetic technique (n = 18 (15%)) and performance of the anaesthesiologist (n = 8 (7%)) were most commonly associated with death. During maintenance, the most common factors were cardiovascular management (n = 43 (36%)), ventilatory management (n = 12 (10%)) and patient monitoring (n = 12 (10%)). In both the recovery and the postoperative phases, patient monitoring was the most common factor (n = 12 (10%) for both). For cardiovascular, ventilatory and other anaesthetic management, human failure contributed to 89 (75%) deaths and organisational factors to 12 (10%). For inadequate patient monitoring, human factors contributed to 71 (60%) deaths and organisational factors to 48 (40%). Other contributing factors were inadequate communication (30 deaths (25%) for all four aspects of the anaesthetic management) and lack of supervision (particularly for ventilatory management). Inadequate care was delivered in 19 (16%) of the anaesthesia-related deaths with respect to cardiovascular management, in 20 (17%) with respect to ventilatory management, in 18 (15%) with respect to patient monitoring and in 23 (19%) with respect to other anaesthetic management.

Notes: To date, anaesthesia-related mortality, morbidity and risk factors have almost exclusively been studied qualitatively rather than quantitatively. Therefore, knowledge of the relative risk associated with many anaesthesia-related factors is still lacking. Recently, a quantitative study of the determinants and prevention of morbidity and mortality in anaesthesia was started in the Netherlands. Its objective is to study severe peri-operative morbidity and mortality as a function of anaesthesia-related risk factors. The study is designed as a case-control study within a prospectively defined cohort. The cohort comprises all patients undergoing an anaesthetic procedure, either general, regional or a combination, in one of 61 hospitals between 1 January 1995 and 1 January 1997. A ‘case’ is a patient who dies within 24 h of undergoing an anaesthetic procedure or who remains comatose 24 h after an anaesthetic procedure. A ‘control’ patient is a randomly chosen patient who has undergone anaesthesia and is matched for gender and age. The present report discusses the study protocol.

Notes: The effects of epidural administration of alfentanil on the intravenous alfentanil dose requirements and the plasma concentrations required to suppress responses to surgical stimulation during nitrous oxide-oxygen-alfentanil anaesthesia in 20 patients undergoing lower abdominal surgery were studied. Before induction of anaesthesia, patients in one group (E) received an epidural injection of 1mg alfentanil, followed by an epidural infusion of alfentanil 0.2mg.h-1 until skin closure, whilst patients in the other group (C, control) received a continuous infusion of sodium chloride via a sham catheter in order to blind the main investigator to the treatment. Anaesthesia was induced and maintained with nitrous oxide (66%) in oxygen and a‘target’-controlled intravenous infusion of alfentanil. During surgery, the‘target’alfentanil concentration was increased or decreased according to patients’responses. The number of responses to surgical stimulation was smaller in patients from group E (median 1, range 0-3) than in patients from group C (median 4, range 1–15; p 〈 0.005), even though the alfentanil intravenous infusion rates were smaller in group E [mean (SD): 1.6(0.5)μg.kg-1min-1] than in group C [2.9(1.2)μg.kg-1min-1, p 〈 0.02]. Both the lowest concentrations associated with no response [133(40)ng.ml-1]and the highest concentrations associated with a response [155(65)ng.ml-1] in group E were lower than those in group C [238(100) ng.ml-1, p 〈 0.01 and 334(163) ng.ml-1, p 〈 0.05, respectively]. We concluded that epidural administration of alfentanil reduces intravenous alfentanil requirements during nitrous oxide-oxygen-alfentanil anaesthesia for lower abdominal surgery. The results indicate a spinal mechanism of action of epidural alfentanil.

Notes: The plasma concentration-time profile of alfentanil following epidural administration was determined in eight patients undergoing lower abdominal surgery under nitrous oxide (66%)-oxygen (33%)-halothane (0.3%) anaesthesia, supplemented with intravenous sufentanil. Alfentanil (1 mg) was administered epidurally before induction of general anaesthesia. Blood samples for the determination of plasma alfentanil concentrations by capillary gas chromatography were collected at intervals until 12h after the epidural injection. Peak plasma concentrations [mean (SD)] were 9.7 (2.3)ng.ml-1, and were attained in a median (range) time of 90 (30-120) min. The results suggest that alfentanil is slowly absorbed from the epidural space into the general circulation.