Randomized study of intravenous fluid preload before epidural analgesia during labour

We performed a randomized controlled trial of the effect ofintravenous fluid preload on maternal hypotension and fetalheart rate (FHR) changes in labour after the first epiduralinjection. Group 1 (49 women) received 1 litre of crystalloidpreload. Group 2 (46 women) received no preload. No statisticallysignificant difference was shown between the two groups foreither of the outcomes. Hypotension was found in three womenin group 1 and five in group 2 (P=0.4). Deterioration in FHRpattern was found in four women in group 1 and 11 in group 2(P=0.08). This study has not shown a significant increase inthe incidence of hypotension when intravenous preload is omittedbefore epidural analgesia using a low concentration of bupivacaineduring labour. Because of the clinical importance of the differencein the rate of FHR deterioration between the two groups, wecontinue to administer preload for high-risk cases. Br J Anaesth 2000; 85: 311–3 Footnotes ^* Correspondingauthor     

Sequential compression device with thigh-high sleeves supports mean arterial pressure during Caesarean section under spinal anaesthesia

Background. This study investigated the use of a SequentialCompression Device (SCD) with thigh-high sleeves and a presetpressure of 50 mm Hg that recruits blood from the lower limbsintermittently, as a method to prevent spinal hypotension duringelective Caesarean section. Possible association of arterialpressure changes with maternal, fetal, haemodynamic, and anaestheticfactors were studied. Methods. Fifty healthy parturients undergoing elective Caesareansection under spinal anaesthesia were randomly assigned to eitherSCD (n=25) or control (n=25) groups. A standardized protocolfor pre-hydration and anaesthetic technique was followed. Hypotensionwas defined as a decrease in any mean arterial pressure (MAP)measurement by more than 20% of the baseline MAP. Systolic (SAP),MAP and diastolic (DAP) arterial pressure, pulse pressure (PP),and heart rate (HR) were noted at baseline and every minuteafter the spinal block until delivery. Results. A greater than 20% decrease in MAP occurred in 52%of patients in the SCD group vs 92% in the control group (P=0.004,odds ratio 0.094, 95% CI 0.018–0.488). There were no significantdifferences in SAP, DAP, HR, and PP between the groups. Conclusion. SCD use in conjunction with vasopressor significantlyreduced the incidence of a 20% reduction of MAP. Br J Anaesth 2003; 91: 695–8     

Subarachnoid haemorrhage following spinal anaesthesia in an obstetric patient

We describe an obstetric patient who presented for removal ofa retained placenta. After insertion of the spinal anaesthetic,she developed a severe headache, and a subarachnoid haemorrhagewas diagnosed. We discuss the differential diagnosis of theheadache, the occurrence of intracranial haemorrhages afterdural puncture and the future management of this patient. Br J Anaesth 2001; 86: 442–4     

Incremental spinal anaesthesia for elective Caesarean section in a patient with Eisenmenger's syndrome

We describe a new approach to anaesthesia for elective Caesareansection in a woman with Eisenmenger’s syndrome. Incrementalregional anaesthesia was performed using a microspinal catheterand haemodynamic monitoring included transthoracic bioimpedancecardiography. This approach allowed the disadvantages of generalanaesthesia and invasive cardiac output monitoring to be avoided. Br J Anaesth 2001; 86: 723–6     

Transcutaneous electrical nerve stimulation at the PC-5 and PC-6 acupoints reduced the severity of hypotension after spinal anaesthesia in patients undergoing Caesarean section

BACKGROUND: Despite prophylactic measures, hypotension remains a common side-effect of spinal anaesthesia for parturients. Electroacupuncture at the Neiguan (PC-6) and Jianshi (PC-5) points influences haemodynamics. We thus hypothesized that transcutaneous electrical nerve stimulation (TENS) at traditionally used acupuncture points would reduce the severity of hypotension after spinal anaesthesia in patients undergoing Caesarean section. METHODS: After obtaining approval from the local ethics committee and written informed patient consent, 36 singleton parturients undergoing Caesarean section under spinal anaesthesia were randomized into three groups. The control group received no treatment, and the acupoint and non-acupoint groups received TENS at the PC-5 and PC-6 points of both arms and non-acupoints of both shoulders, respectively. RESULTS: The median (range) of the lowest recorded systolic blood pressure was significantly higher in the acupoint group compared with the other groups and that of the non-acupoint group was higher than that of the control group [control, 70 (68-82) mm Hg; acupoint, 94 (84-109) mm Hg; non-acupoint, 81 (70-92) mm Hg: P<0.001]. Significantly more parturients in the control and non-acupoint groups experienced hypotension [control, 10 (83%); acupoint, 4 (33%); non-acupoint, 10 (83%): P=0.013]. More ephedrine was required to maintain arterial blood pressure in the control and non-acupoint groups. CONCLUSIONS: TENS on the traditional acupuncture points reduced the severity and incidence of hypotension after spinal anaesthesia in parturients.     

Cough reflex sensitivity after elective Caesarean section under spinal anaesthesia and after vaginal delivery

BACKGROUND: In pregnancy, airway oedema and heartburn may increase cough sensitivity, whereas spinal anaesthesia (SA) with local anaesthetics and opiates may decrease it. Decreased cough sensitivity increases the risk for pneumonia or retained secretions. The aim of this study was to determine whether cough sensitivity is increased in pregnant patients and if it is decreased after planned Caesarean section (CS) under SA. METHODS: Twenty-seven non-pregnant volunteers, 27 patients after vaginal delivery (VD group), and 28 patients after CS under SA (CS group) were studied. For SA, hyperbaric bupivacaine 8-12 mg, sufentanil 5 microg, and morphine 100 microg was given. Increasing concentrations of nebulized citric acid were delivered until eliciting cough. The concentration eliciting one (C1) and two coughs (C2) were recorded and log transformed for analysis (log C1 and log C2). RESULTS: Median (inter-quartile) log C1 was 1.3 (0.6) mg ml(-1) in the VD group, 1.6 (0.6) mg ml(-1) in the non-pregnant group (P < 0.01 vs VD group), and 2.2 (0.7) mg ml(-1) in the CS group (P < 0.0001 and P < 0.01 vs VD and non-pregnant groups, respectively). Similar results were observed with log C2. In CS group, log C1 and log C2 remained increased up to 4 h after SA. CONCLUSIONS: Cough sensitivity was increased after VD but decreased for up to 4 h after SA.     

Small-dose selective spinal anaesthesia for short-duration outpatient gynaecological laparoscopy: recovery characteristics compared with propofol anaesthesia

A randomized controlled trial compared recovery characteristicsafter selective spinal anaesthesia (SSA) or propofol generalanaesthesia (GA) for short-duration outpatient laparoscopicsurgery. Forty women were randomized to receive either SSA (1%lidocaine 10 mg, sufentanil 10 µg and sterilewater 1.8 ml) or GA (propofol and nitrous oxide 50% inoxygen). Compared with the GA group, times to leaving the operatingroom, performing a straight leg raise, performing deep knee-bendsand achieving an Aldrete score >9 and the time in Phase IIrecovery were significantly shorter (P<0.05) in the SSA group. Br J Anaesth 2001; 86: 570–2     

Successful epidural anaesthesia for Caesarean section in a patient with spondyloepiphyseal dysplasia

Spondyloepiphyseal dysplasia congenita is a rare genetic entityin which it is very important to involve anaesthetists earlyon to discuss the possible anaesthetic complications for bothgeneral or regional anaesthesia. A case is described of a patientwith spondyloepiphyseal dysplasia and multifetal pregnancy inwhich successful epidural anaesthesia for caesarean sectionwas performed. Br J Anaesth 2001; 86: 133–4     

Comparison of phenylephrine infusion regimens for maintaining maternal blood pressure during spinal anaesthesia for Caesarean section

Background. During spinal anaesthesia for Caesarean section,the optimal phenylephrine regimen and the optimal blood pressure(BP) to which it should be titrated are undetermined. The idealregimen would balance efficacy for maintaining uteroplacentalperfusion pressure against potential for uteroplacental vasoconstriction,both of which may affect fetal acid–base status. We comparedphenylephrine infusion regimens based on three different BPthresholds. Methods. After intrathecal injection, we infused phenylephrine100 µg min^–1 for 2 min. Then, until delivery,we infused phenylephrine whenever systolic BP (SBP), measuredevery 1 min, was below a randomly assigned percentage of baseline:100% (Group 100, n=25), 90% (Group 90, n=25) or 80% (Group 80,n=24). We compared umbilical blood gases, Apgar scores and maternalhaemodynamics and symptoms. Results. Patients in Group 100 had fewer episodes [median 0(range 0–8)] of hypotension (SBP <80% baseline) comparedwith Group 80 [5 (0–18)] and Group 90 [2 (0–7)](P<0.001 in each instance). Total dose of phenylephrine wasgreater in Group 100 [median 1520 µg (interquartile range1250–2130 µg)] compared with Group 90 [1070 (890–1360)µg] and Group 80 [790 (590–950) µg]. Umbilicalarterial pH was greater in Group 100 [mean 7.32 (95% confidenceinterval 7.31–7.34)] than in Group 80 [7.30 (7.28–7.31)](P=0.034). No patient had umbilical arterial pH <7.2. InGroup 100, 1/24 (4%) patients had nausea or vomiting comparedwith 4/25 (16%) in Group 90 and 10/25 (40%) in Group 80 (P=0.006). Conclusions. For optimal management, phenylephrine should betitrated to maintain maternal BP at near-baseline values. Br J Anaesth 2004; 92: 469–74     

Dural ectasia: a likely cause of inadequate spinal anaesthesia in two parturients with Marfan's syndrome

We report two cases of Caesarean section in patients with Marfan'ssyndrome where continuous subarachnoid anaesthesia failed toprovide an adequate surgical block. This was possibly becauseof dural ectasia, which was confirmed by a computed tomographyscan in both cases.     

Cranial subdural haematoma after spinal anaesthesia

Intracranial subdural haematoma is an exceptionally rare complicationof spinal anaesthesia. A 20-yr-old male underwent appendicectomyunder partial spinal and subsequent general anaesthesia. A weeklater, he presented with severe headache and vomiting not respondingto bed rest and analgesia. Magnetic resonance imaging showeda small acute subdural haematoma in the right temporo-occipitalregion. The patient improved without surgical decompression.The pathogenesis of headache and subdural haematoma formationafter dural puncture is discussed and the literature brieflyreviewed. Severe and prolonged post-dural puncture headacheshould be regarded as a warning sign of an intracranial complication. Br J Anaesth 2001; 86: 893–5     

Prophylactic phenylephrine and fluid co-administration to reduce spinal hypotension during elective caesarean section in a resource-limited setting: a prospective alternating intervention study

Spinal hypotension is a common and clinically important problem during caesarean section. Current consensus recommendations for resource-rich settings suggest the use of a titrated phenylephrine infusion, in combination with fluid coloading, for prevention of maternal hypotension. In resource-limited settings, where syringe drivers are unavailable, these recommendations advise the addition of 500 μg phenylephrine to the first 1 l of intravenous fluid given after initiation of spinal anaesthesia, with additional vasopressor boluses as required. This prospective, alternating intervention study compared the use of a conventional phenylephrine rescue bolus strategy for prevention of hypotension, defined as systolic arterial pressure < 90 mmHg, with a phenylephrine infusion given according to the consensus recommendation. We studied 300 women having elective caesarean section. There were 77 (51%) women who developed hypotension in the bolus group vs. 55 (37%) in the phenylephrine infusion group (p = 0.011). This represented a 29% reduction in hypotension, with a number needed to treat of 6.8. The six highest systolic arterial pressure readings occurred in the phenylephrine infusion group (range 166–188 mmHg), and there were four instances of bradycardia (heart rate < 50 beats.min⁻¹) with preserved systolic arterial pressure in each group. There were no adverse clinical sequelae, and no differences in neonatal Apgar scores in either group. The consensus recommendation for phenylephrine and fluid co-administration in resource-limited settings appears effective in preventing maternal hypotension, but at the cost of sporadic systolic hypertension.     

A randomised trial comparing 5 mL/kg and 10 mL/kg of pentastarch as a volume preload before spinal anaesthesia for elective caesarean section

BACKGROUND: Colloid solutions are more effective at preventing hypotension than crystalloids when used as a volume preload before caesarean delivery under spinal anaesthesia. The ideal volume to infuse has not been established. METHOD: In a randomised double-blind trial 70 women presenting for elective caesarean section received either 5 mL/kg of pentastarch (group A) or 10 mL/kg of pentastarch (group B) as a volume preload before spinal anaesthesia. Hypotension was defined as a systolic pressure below 90 mmHg or a decrease of 30% from a baseline value. Treatment was with 6-mg increments of ephedrine until resolution. RESULTS: In group B, 7/35 patients (20%) developed hypotension, significantly fewer than the 15/35 (42.8%) in group A (P<0.05). The patients in group B also required less ephedrine (total in group, 114 mg) than those in group A (total in group, 198 mg) CONCLUSIONS: Pentastarch, 10 mL/kg is more effective than 5 mL/kg at preventing hypotension following spinal anaesthesia for caesarean delivery.     

Haemodynamic effects of three doses of dihydroergotamine during spinal anaesthesia

We performed a randomized study comparing the haemodynamic effectsof three doses of the vasopressor dihydroergotamine (DHE) (5,10 and 15 µg kg^–1) in 30 ASA 1 and 2 patients,aged 53–87 yr, undergoing spinal anaesthesia. Non-invasivesystolic arterial pressure (SAP), heart rate and central venouspressure (CVP) were recorded continuously for 25 min. Intravenousfluids were withheld during this period. All three doses ofDHE reversed the lowering effects of spinal anaesthesia on SAPand CVP (P<0.0001), and these effects were smooth in onsetand sustained. Whereas the lowest (5 µg kg^–1)dose restored SAP and CVP to near prespinal values, the higher(10 and 15 µg kg^–1) doses resulted inabove-baseline increases in SAP of 7% and in CVP of 2.7 cm H₂O(P<0.05). The haemodynamic profile of DHE makes it a usefulagent for managing hypotension during spinal anaesthesia. Adose of 5–10 µg kg^–1 is recommended. Br J Anaesth 2001; 87: 499–501     

Unusually early onset of post-dural puncture headache after spinal anaesthesia using a 27G Whittacre needle

We present a case of a post-dural puncture headache occurring20 min after spinal anaesthesia using a 27-Gauge Whittacre needle.The unusually early occurrence of this complication is thoughtto be the first of its kind reported in the literature and highlightsthe novelty of this case.     

Minimum dose of intrathecal diamorphine required to prevent intraoperative supplementation of spinal anaesthesia for Caesarean section

Background. Intraoperative discomfort during spinal anaesthesiafor Caesarean section is the commonest cited anaesthetic causeof litigation in obstetric practice. Intrathecal opioids areused to improve intraoperative comfort and postoperative analgesiafor these operations. The minimum intrathecal diamorphine dosethat prevents intraoperative supplementation requires determination. Method. After ethics committee approval, 200 ASA I, II womenwith     

Crystalloid versus colloid for circulatory preload for epidural Caesarean section

Sixty mothers were randomly allocated to receive either 2 litres of crystalloid or 1 litre of colloid solution (hydroxyethyl starch) in order to preload the circulation prior to elective Caesarean section under epidural anaesthesia. There were no differences in the incidence of hypotension, degree of haemodilution, umbilical cord blood gas tensions or umbilical blood osmolalities between the two groups.     

Prevention of hypotension after spinal anaesthesia for caesarean section: a systematic review and network meta-analysis of randomised controlled trials

Spinal anaesthesia for caesarean section commonly causes maternal hypotension. This systematic review and network meta-analysis compared methods to prevent hypotension in women receiving spinal anaesthesia for caesarean section. We selected randomised controlled trials that compared an intervention to prevent hypotension with another intervention or inactive control by searching MEDLINE and Embase, Web of Science to December 2018. There was no language restriction. Two reviewers extracted data on trial characteristics, methods and outcomes. We assessed risk of bias for individual trials (Cochrane tool) and quality of evidence (GRADE checklist). We assessed 109 trials (8561 women) and 12 different methods that resulted in 30 direct comparisons. Methods ranked by OR (95%CI) from most effective to least effective were: metaraminol 0.11 (0.04–0.26); norepinephrine 0.13 (0.06–0.28); phenylephrine 0.18 (0.11–0.29); leg compression 0.25 (0.14–0.43); ephedrine 0.28 (0.18–0.43); colloid given before induction of anaesthesia 0.38 (0.24–0.61); angiotensin 2, 0.12 (0.02–0.75); colloid given after induction of anaesthesia 0.52 (0.30–0.90); mephentermine 0.09 (0.01–1.30); crystalloid given after induction of anaesthesia 0.78 (0.46–1.31); and crystalloid given before induction of anaesthesia 1.16 (0.76–1.79). Phenylephrine caused maternal bradycardia compared with control, OR (95%CI) 0.23 (0.07–0.79). Ephedrine lowered umbilical artery pH more than phenylephrine, standardised mean difference (95%CI) 0.78 (0.47–1.49). We conclude that vasopressors should be given to healthy women to prevent hypotension during caesarean section with spinal anaesthesia.     

Evaluation of the efficacy of elastic compression stockings in prevention of hypotension during epidural anaesthesia for elective caesarean section

The ability of graduated compression elastic stockings to prevent hypotension during elective epidural caesarean section was evaluated. Twenty women were randomly assigned to two groups of ten, one group being fitted with the stockings. The incidence and degree of hypotension were the same in both groups. Graduated compression elastic stockings are of no benefit in reducing the incidence of maternal hypotension during caesarean section.     

Development of a difficulty score for spinal anaesthesia

Background. Multiple attempts at spinal puncture may be hazardous.Accurate preoperative prediction of difficulty adds to the deliveryof high quality care. This clinical trial was designed to: (i)determine the predictive performance of difficulty variables;(ii) compare senior and junior anaesthetists; (iii) developa score to predict difficulty during the performance of spinalanaesthesia. Methods. A total of 300 patients subjected to urological proceduresand scheduled for spinal anaesthesia were independently assessedand stratified according to the categories of the difficultypredictors of spinal anaesthesia into one of nine grades (0–8)and randomized according to the experience of the anaesthetistinto two groups (group A, staff with more than 15 yrs’experience; group B, resident with more than 6 months but lessthan 1 yr in training). The number of attempts and levels, andsuccess rate of the technique were the outcome variables. Datawere analysed by multivariate analysis and receiver operatingcharacteristic (ROC) curves. Results. The bony landmarks of the back and the radiologicalcharacteristics of the lumbar vertebrae were two independentpredictors of difficulty. Multivariate analysis indicated differencesbetween junior and senior staff but ROC curves indicated nodifference. Grade 4 was the difficulty score at or above whichdifficulty was expected whether or not radiological characteristicsof the vertebrae were included. Conclusions. Spinal bony landmarks and radiological characteristicsof the lumbar vertebrae are independent predictors of difficultyduring spinal anaesthesia. There is no difference between seniorand junior anaesthetists. Grade 4 is the difficulty score ator above which difficulty is expected. Br J Anaesth 2004; 92: 354–60