Adverse side effects and route of administration of opioids in combined spinal-epidural analgesia for labour: a meta-analysis of randomised trials.

BACKGROUND: Studies report an increased risk of maternal and fetal adverse side effects when combined spinal-epidural, rather than standard epidural, analgesia is provided for labour and delivery. Intrathecal opioids used with local anaesthetic in combined spinal-epidural analgesia may be a cause. It is not known whether this is due to the addition of opioid to local anaesthetic in the intrathecal space only or due to concomitant administration into the intrathecal and epidural spaces. METHODS: We searched for randomised trials comparing maternal, obstetrical and neonatal outcomes in parturients having combined spinal-epidural or standard epidural analgesia, and compared subgroups of patients according to the route of administration of opioids in combined spinal-epidural techniques. Studies were evaluated for eligibility and quality. Fixed and random-effects models were used for pooled data analysis and outcomes were compared using relative risk (RR) or mean difference with 95% confidence intervals (CI). RESULTS: We identified 1658 reports and 41 fully published randomised controlled trials. In patients who received combined spinal-epidural techniques, an increased risk of nausea/vomiting (RR 1.31, CI 1.0 to 1.72), pruritus (RR 4.26, CI 2.59 to 7.0) and fetal bradycardia (RR 2.38, CI 1.57 to 3.62) was observed regardless of the route of administration. In contrast, hypotension occurred more frequently after combined intrathecal and epidural opioid (RR 1.54, 1.22 to 1.93; P-value 0.02 for subgroup difference). CONCLUSION: For combined spinal-epidural techniques, the administration of opioids in combination with local anaesthetic, particularly when used in both the intrathecal and epidural space, should be carefully considered.

[Surface recording of abnormal post-QRS micropotentials. Description and frequency in ventricular tachycardias after myocardial infarction]. / Enregistrement de surface des micropotentiels anormaux post-QRS. Description et fréquence dans les tachycardies ventriculaires après infarctus du myocarde.

In order to study abnormal post-QRS micropotentials, so called late potentials, and to determine their frequency in post myocardial infarction ventricular tachycardia (VT), high amplification electrocardiogrammes were recorded in 180 patients classified in 3 different groups: Group A comprising 36 patients who developed sustained VT after myocardial infarction; Group B comprising 124 patients with myocardial infarction uncomplicated by VT. This group was subdivided into subgroup B1 (retrospective study of 35 patients with chronic myocardial infarction, dating on average 10 months--range 7 days to 8 years) and subgroup B2 (prospective study of 89 patients investigated on the 7th and 60th days after infarction); Group C comprising 20 young, normal control subjects. Using computer assisted high amplification electrocardiography, all patients underwent at least 3 successive recordings of the following parameters: averaging 100 cycles; sampling: 1 kHz; band pass 20-300 Hz and 80-300 Hz; gain setting 10,000 and 25,000. Late potentials usually appears, after the end of the S wave, as high frequency oscillations with an amplitude (10 to 20 microV) significantly greater than that of the background noise. Our recordings also showed: the frequent presence, especially in intraventricular blocks, of fragmentation of the end of the R wave and of the S wave or terminal potentials; the presence of an abnormal giant low frequency high amplitude wave (40 to 80 microV) in 5 patients with a large left ventricular aneurysm.(ABSTRACT TRUNCATED AT 250 WORDS)