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A Cyna

Publications and source records attributed to A Cyna.

11 recordsLinked to original sources
PubMed2004

Prophylactic intravenous preloading for regional analgesia in labour.

BACKGROUND: Reduced uterine blood flow from maternal hypotension may contribute to fetal heart rate changes which are common following regional analgesia (epidural or spinal or combined spinal-epidural (CSE)) during labour. Intravenous fluid preloading may help to reduce maternal hypotension but using lower doses of local anaesthetic, and opioid only blocks, may reduce the need for preloading. OBJECTIVES: To assess the effects of prophylactic intravenous fluid preloading before regional analgesia during labour on maternal and fetal well-being. SEARCH STRATEGY: We searched the Cochrane Pregnancy and Childbirth Group trials register (19 February 2004). SELECTION CRITERIA: Randomised and quasi-randomised trials comparing prophylactic intravenous preloading before regional analgesia during labour with a control group (dummy or no preloading). DATA COLLECTION AND ANALYSIS: Two reviewers independently applied eligibility criteria, assessed trial quality and extracted data. MAIN RESULTS: Six studies are included (473 participants). In one epidural trial using high-dose local anaesthetic, preloading with intravenous fluids was shown to counteract the hypotension which frequently follows traditional epidural analgesia (relative risk (RR) 0.07, 95% confidence interval (CI) 0.01 to 0.53; 102 women). This trial was also associated with a reduction in fetal heart rate abnormalities (RR 0.36, 95% CI 0.16 to 0.83; 102 women); no differences were detected in other perinatal and maternal outcomes for this trial and another high-dose epidural trial. In the two epidural low-dose anaesthetic trials, no significant difference in maternal hypotension was found (RR 0.73, 95% CI 0.36 to 1.48; 260 women), although they were underpowered to detect less than a very large effect. No significant differences were seen between groups in these trials for fetal heart rate abnormalities (RR 0.64, 95% CI 0.39 to 1.05; 233 women). In the two CSE trials, no differences were reported between preloading and no preloading groups. In the spinal/opioid trial, the RR for hypotension was 0.89, 95% CI 0.43 to 1.83 (40 women) and 0.70, 95% CI 0.36 to 1.37 for fetal heart rate abnormalities (32 women). In the opioid only study (30 women), there were no instances of hypotension or fetal heart rate abnormalities in either group. REVIEWERS' CONCLUSIONS: Preloading prior to traditional high-dose local anaesthetic blocks may have some beneficial fetal and maternal effects in healthy women. Low-dose epidural and CSE analgesia techniques may reduce the need for preloading. The studies reviewed were too small to show whether preloading is beneficial for women having regional analgesia during labour using the lower-dose local anaesthetics or opioids. Further investigation of low-dose epidural or CSE (including opioid only) blocks, and the risks and benefits of intravenous preloading for women with pregnancy complications, is required.

Anesthesia, Epidural↗
PubMed2001

Laryngeal mask vs intubating laryngeal mask: insertion and ventilation by inexperienced resuscitators.

The laryngeal mask airway (LMA) has been shown to be useful in airway maintenance during resuscitation. The intubating laryngeal mask (ILM) is a modified LMA permitting both ventilation and rapid endotracheal intubation. We aimed to compare the LMA and the ILM with regard to ease of insertion and successful ventilation by inexperienced personnel. We have used anaesthetized, apnoeic, non-paralysed patients as a model to simulate resuscitation. Following standardized training, non-anaesthetic medical staff with no previous experience in laryngeal mask airway insertion (novices) inserted either the LMA or ILM in 55 patients following induction of anaesthesia. There were no differences between the two patient groups included in our study with regard to mean age and body mass index (BMI). The success rate for inserting the airway device and achieving a significant end-tidal CO2 recording within two minutes was 23/28 for the LMA (82.1%) and 22/27 for the ILM (81.5%). Reasons for failure included inability to insert the ILM past the teeth and insertion of the LMA upside down. There were no clinically relevant differences in the mean time to airway insertion and successful ventilation (62.6 vs 62 seconds) or expired tidal volume (781 vs 767 ml) for the LMA and ILM respectively. We conclude that the ILM is as easily inserted and effectively used as an LMA by novices and, because it allows the option offacilitating endotracheal intubation, may be the preferred device for maintaining an airway during resuscitation.

Adult↗
PubMed1999

Epidural analgesia for labour and delivery in a parturient with congenital hypertrophic obstructive cardiomyopathy.

We report a parturient delivering vaginally at term with symptomatic congenital hypertrophic obstructive cardiomyopathy. Epidural analgesia was used during labour and delivery and is likely to have made a useful contribution to the successful outcome. Although controversial, reported use of epidural analgesia during labour for hypertrophic obstructive cardiomyopathy parturients has been generally positive. A multi-disciplinary team approach, early anaesthetic assessment and a carefully managed epidural catheter inserted in early labour can optimize analgesia and minimize the stresses of labour and vaginal delivery provided the risks of reduced preload and afterload are minimized.

Adult↗
PubMed1999

Incidents in obstetric anaesthesia and analgesia: an analysis of 5000 AIMS reports.

We aimed to explore the first 5000 incidents reported to the Australian Incident Monitoring Study (AIMS) involving anaesthesia for obstetric patients and found 203 such incidents. Analysis and classification identified seven main incident groups; regional anaesthetic techniques (33%), anaesthetic equipment problems (13%), "wrong drug" errors (10%), other drug-related problems (16%), difficult/failed intubation (9%), problems with the endotracheal tube (9%) and other problems (10%). When compared to the incidents in the main database, obstetric cases were found to be over-represented with respect to accidental dural puncture, post dural puncture headache, failed intubation in emergency situations and the incidence of certain types of "wrong drug" error. The implications of these reports regarding safe practice of obstetric anaesthesia are discussed.

Analgesia, Obstetrical↗
PubMed1990

AURA: a new respiratory monitor.

The Aberdeen University Respiratory Alarm (AURA) is designed to monitor the respiratory rate and the inter- expiratory period (respiratory gap) in the spontaneously breathing patient using polarised polyvinylidene fluoride sensors incorporated in the Oxygen delivery mask. The monitor is composed of three modules--the sensor module includes a pair of polyvinylidene film strips mounted on the inner surface of the Oxygen mask. The difference in temperature between the ambient Oxygen enriched air and the warmer expired air allows the pyroelectric property of the sensors to be harnessed. The sensor arrangement allows a differential signal to develop between them which is amplified, filtered and rectified prior to triggering a counter. The timing module is based on a 32,768 Hz crystal oscillator that generates pulses allowing the period between expirations to be measured and compared to the maximum allowable period set by the user. The respiratory rate is also measured and compared to the minimum set by the user using EPROMS and comparators. The display module consists of a bar-graph display of the level of the sensed signal with each breath with a soft audible click. Eight segment LEDs are used to provide a digital display of the respiratory rate and the respiratory gap. Audiovisual alarms are triggered when the rate falls short of the set rate and/or when the gap exceeds the set gap. The need for continuous respiratory monitoring of the spontaneously breathing adult in hospital practice led us to develop this prototype with sensors whose design and configuration can be considerably improved.

Adult↗