Permanent hearing loss and tinnitus following epidural analgesia complicated by accidental dural puncture.

We report a case of permanent high-frequency hearing loss and tinnitus in a 38-year-old woman following an unrecognised dural puncture during epidural placement. The patient reported subjective unilateral hearing loss and tinnitus, along with a post-dural puncture headache, four hours post-delivery. The patient's headache resolved following two epidural blood patches, however, hearing loss and tinnitus persisted longer than two years. Long-term auditory symptoms following epidural analgesia in labour are very unusual findings.

Comparison of transversus abdominis plane block vs spinal morphine for pain relief after Caesarean section.

BACKGROUND: Transversus abdominis plane (TAP) block is an alternative to spinal morphine for analgesia after Caesarean section but there are few data on its comparative efficacy. We compared the analgesic efficacy of the TAP block with and without spinal morphine after Caesarean section in a prospective, randomized, double-blinded placebo-controlled trial. METHODS: Eighty patients were randomized to one of four groups to receive (in addition to spinal anaesthesia) either spinal morphine 100 µg (S(M)) or saline (S(S)) and a postoperative bilateral TAP block with either bupivacaine (T(LA)) 2 mg kg(-1) or saline (T(S)). RESULTS: Pain on movement and early morphine consumption were lowest in groups receiving spinal morphine and was not improved by TAP block. The rank order of median pain scores on movement at 6 h was: S(M)T(LA) (20 mm)

Ultrasound in obstetric anaesthesia: a review of current applications.

Ultrasound equipment is increasingly used by non-radiologists to perform interventional techniques and for diagnostic evaluation. Equipment is becoming more portable and durable, with easier user-interface and software enhancement to improve image quality. While obstetric utilisation of ultrasound for fetal assessment has developed over more than 40years, the same technology has not found a widespread role in obstetric anaesthesia. Within the broader specialty of anaesthesia; vascular access, cardiac imaging and regional anaesthesia are the areas in which ultrasound is becoming increasingly established. In addition to ultrasound for neuraxial blocks, these other clinical applications may be of value in obstetric anaesthesia practice.

Use of recombinant factor VIIa in massive post-partum haemorrhage.

BACKGROUND AND OBJECTIVE: Massive post-partum haemorrhage continues to be one of the world's leading causes of maternal morbidity and mortality. Any new treatment that potentially helps at risk parturients should be thoroughly investigated. Recombinant factor VIIa (rVIIa) is increasingly being used in the treatment of massive haemorrhage. We performed a case-matched analysis of its use since 2003 in the treatment of massive post-partum haemorrhage at our hospital. METHODS: Twenty-eight cases of massive post-partum haemorrhage were identified over a 3-yr period since 2003. In six of these cases, rVIIa was used as part of their management. Six case-matched controls were sought. The six women with the greatest requirement for packed red cell transfusion who also had a deranged prothrombin time were included. The groups were then compared for differences. The worst prothrombin time in each group was noted as was the best prothrombin time within 6 h, this was used as our measure of response to treatment. RESULTS: There was no statistical difference in age, gestation, parity, transfusion requirements, mode of delivery or the severity of the coagulopathy between the two groups. In both groups the prothrombin time improved with management. There was no significant difference in either the magnitude of the improvement in the value of the prothrombin time or the absolute value of the best prothrombin time (P = 0.09). Five out of the six women in the rFVIIa group had normal or low prothrombin times within 6 h yet only one woman who did not receive rFVIIa had a normal prothrombin time within 6 h though this was not significant (P = 0.08). CONCLUSIONS: This case-matched analysis supports the management of massive post-partum haemorrhage with appropriate resuscitation, surgical intervention and use of blood and blood products. This study does not support the routine use of rFVIIa in the management of massive obstetric haemorrhage. rFVIIa may have a role to play in this management but further studies and analyses will be required.

Hemodynamic effects of spinal anesthesia and simultaneous intravenous bolus of combined phenylephrine and ephedrine versus ephedrine for cesarean delivery.

BACKGROUND: Hypotension following spinal anesthesia for cesarean delivery can produce adverse maternal symptoms and neonatal acid-base effects. Single-agent prophylaxis, most notably with ephedrine, does not reliably prevent spinal anesthesia-induced hypotension; recently, however, the prophylactic use of phenylephrine with ephedrine as an infusion was observed to be effective. We postulated that this combination, when given as an intravenous bolus for prophylaxis and rescue treatment, could be similarly effective. METHOD: Forty-three term parturients were randomized to receive a bolus of ephedrine 10 mg +/- phenylephrine 40 microg (groups E and EP, respectively) simultaneously with spinal anesthesia. Hypotension was defined as a systolic blood pressure below 100 mmHg or a decrease of 20% from a baseline value. Rescue boluses comprised of ephedrine 5 mg +/- phenylephrine 20 microg. RESULTS: For groups E and EP, respectively, the incidence of hypotension was 80% vs. 95% (P=0.339), with the mean number of rescue boluses being 3.85+/-3.7 and 3.05+/-1.7 and the mean umbilical artery pH being 7.246+/-0.081 vs. 7.244+/-0.106. All comparisons were not significant (NS). CONCLUSION: The combination of ephedrine and phenylephrine given as an intravenous bolus at the doses selected is not superior to ephedrine alone in preventing or treating hypotension in healthy parturients undergoing cesarean delivery.

Interleukin-1 beta rapidly inhibits aortic endothelium-dependent relaxation by a DNA transcription-dependent mechanism.

OBJECTIVES: This study examined the effects of interleukin-1 beta on isometric tension development and relaxation in isolated rat aortic rings in response to the alpha-1 adrenergic agonist phenylephrine, the endothelium-dependent vasodilator acetylcholine, and the endothelium-independent vasodilator sodium nitroprusside. DESIGN: Randomized, controlled, paired design. SETTING: Animal laboratory within a university department of physiology. SUBJECTS Paired aortic thoracic aortic rings from specific pathogen-free Sprague-Dawley rats. INTERVENTIONS: Series I examined the potential for interleukin-1 beta to cause early arterial endothelial dysfunction. Paired aortic rings were incubated for 2 hrs with interleukin-1 beta or vehicle. Series II examined the potential for inhibition of DNA transcription to attenuate interleukin-1 beta-mediated endothelial dysfunction. Paired rings received either dactinomycin or vehicle before interleukin-1 beta incubation. Series III quantified the degree to which inhibition of DNA transcription inhibited early interleukin-1 beta-mediated endothelial dysfunction. Paired rings received either dactinomycin pretreatment followed by interleukin-1 beta incubation, or pretreatment and incubation with inert vehicles. Series IV assessed the effects of interleukin-1 beta on responsiveness to an exogenous nitric oxide donor, sodium nitroprusside, in the presence of the nitric oxide synthesis inhibitor N omega-nitro-L-arginine methyl ester. MEASUREMENTS AND MAIN RESULTS: Incubation with interleukin-1 beta for 2 hrs had no effect on contractile response but attenuated endothelium-dependent relaxation significantly relative to control. Dactinomycin pretreatment inhibited early interleukin-1 beta-mediated endothelial dysfunction. The combination of interleukin-1 beta and dactinomycin produced effects on endothelium-dependent relaxation that were not different from that seen in rings not exposed to interleukin-1 beta. Interleukin-1 beta attenuated responsiveness to sodium nitroprusside relative to control. CONCLUSIONS: Interleukin-1 beta causes an early impairment of endothelium-dependent vasorelaxation with an onset that precedes its effects on systemic contractility. This impairment occurs via a mechanism that is wholly or predominantly dependent on DNA transcription. The altered vasorelaxation induced by interleukin-1 beta is at least partly mediated by a reduction in nitric oxide responsiveness.

Prophylactic intravenous bolus ephedrine for elective Caesarean section under spinal anaesthesia.

BACKGROUND AND OBJECTIVE: To evaluate the efficacy and optimal dose of prophylactic intravenous ephedrine for the prevention of maternal hypotension associated with spinal anaesthesia for Caesarean section. METHODS: After patients had received an intravenous preload of 0.5 L of lactated Ringer's solution, spinal anaesthesia was administered in the sitting position with hyperbaric bupivacaine 2.5 mL 0.5% combined with 25 microg fentanyl. A total of 68 patients were randomized to receive a simultaneous 2 mL bolus intravenously of either 0.9% saline (Group C, n = 20), ephedrine 6 mg (Group E-6, n = 24), or ephedrine 12 mg (Group E-12, n = 22). Further rescue boluses of ephedrine 6 mg were given if systolic arterial pressure fell to below 90 mmHg, greater than 30% below baseline, or if symptoms suggestive of hypotension were reported. RESULTS: There was a significantly higher incidence of hypotension in Group C (60% patients) compared to Group E-12 (27%), but not in Group E-6 (50%). The 95% Confidence Interval for the difference in proportions between Groups C and E-12 was 6-60%, P < 0.05. Fewer rescue boluses of ephedrine were required in Group E-12 compared with Group C (1.8 +/- 1.2 vs. 3.3 +/- 2.1, P < 0.05). There were no significant differences in the incidence of maternal nausea or vomiting, or of neonatal acidaemia between groups. CONCLUSION: A prophylactic bolus of ephedrine 12 mg intravenously given at the time of intrathecal block, plus rescue boluses, leads to a lower incidence of hypotension following spinal anaesthesia for elective Caesarean section compared to intravenous rescue boluses alone.

High dependency care: impact of lack of facilities for high-risk surgical patients.

BACKGROUND: The difference between the level of care available on general ward areas and intensive care units (ICUs) has resulted in the development of high dependency units (HDUs). AIMS: This study examined the current perioperative management techniques and clinical care settings of high-risk surgical patients in a hospital without a HDU. METHODS: A prospective audit of high-risk surgical patients was performed over an eight-week period. Using a pre-operative questionnaire, the anaesthetist categorised patient suitability for one of three post-operative care areas. In addition, desired and actual post-operative monitoring, pain management and organ support were indicated. RESULTS: Seven (25%) of 28 patients admitted to ICU were rated HDU suitable indicating inappropriate use of resources, while 27 (75%) of 36 patients admitted to the general ward were categorised as fulfilling HDU admission criteria. A total of 21/27 (78%) and 12/27 (44%) of this latter group had alteration of idealised post-operative pain management and haemodynamic invasive monitoring plans respectively. CONCLUSIONS: The absence of an intermediate care area facility in a tertiary hospital without an acute pain team impacts on the type of perioperative care provided to patients and the optimal use of resources.