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     

Randomized controlled study of colloid preload before spinal anaesthesia for caesarean section

We randomized women having elective Caesarean section to receiveeither no preload (control group, n=33) or 4% gelatin solution(Gelofusine) 15 ml kg^–1 (colloid group, n=35)i.v. before spinal anaesthesia. Intravenous metaraminol wastitrated at 0.25–0.75 mg min^–1 to maintainsystolic arterial pressure (SAP) in the target range 90–100%of baseline after the spinal injection. The control group requiredmore vasopressor in the first 10 min [median 1.7 (range 0–2.9)mg vs 1.4 (0–2.8), P=0.02] at a greater maximum infusionrate [0.5 (0–0.75) vs 0.25 (0–0.5) mg min^–1,P=0.0005] and had a lower minimum SAP [90 (51–109) vs101 (75–127) mm Hg, P=0.006] than the colloid group. Nauseawas less frequent in the colloid group (6 vs 24%) but neonataloutcome was similar in the two groups. Colloid preload improvedhaemodynamic stability but did not affect neonatal outcome whenarterial pressure was maintained with an infusion of metaraminolduring spinal anaesthesia for Caesarean section. Br J Anaesth 2001; 87: 772–4     

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     

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.     

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     

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     

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     

Evaluation of pre-emptive intramuscular phenylephrine and ephedrine for reduction of spinal anaesthesia-induced hypotension during Caesarean section

Pre-emptive intramuscular (i.m.) vasopressors were evaluatedin 108 patients undergoing elective Caesarean section underspinal anaesthesia, assigned to four groups in a randomized,double-blind, placebo-controlled study. Group 1 received pre-emptivephenylephrine 4 mg i.m., group 2 received phenylephrine 2 mgi.m., group 3 received ephedrine 45 mg i.m., while controlsreceived an i.m. injection of saline, all given immediatelyafter induction of spinal anaesthesia. Hypotension was definedas a 25% decrease in mean arterial pressure (MAP). Rescue intravenous(i.v.) boluses of ephedrine were given if the patient was hypotensiveor reported nausea, vomiting or dizziness. The incidence ofhypotension was 33% in the phenylephrine 4 mg group comparedwith 70% in the control and phenylephrine 2 mg groups (P=0.03),and 48% in the ephedrine 45 mg group. The phenylephrine 4 mgand ephedrine 45 mg groups had a significantly lower percentagereduction in MAP (–21 (SD 14)% and –22 (14)%) comparedwith controls (–32 (18)%, P=0.04). They also had a lowertotal dose of rescue i.v. ephedrine (15.7 (15.7) mg and 15.8(15.6) mg) compared with controls (28.8 (20.6) mg, P=0.02).We conclude that pre-emptive i.m. phenylephrine 4 mg and ephedrine45 mg reduce the severity of hypotension and the total doseof rescue i.v. ephedrine during spinal anaesthesia for Caesareansection. Br J Anaesth 2001; 86: 372–6     

Haemodynamic effects of oxytocin given as i.v. bolus or infusion on women undergoing Caesarean section

Background. The cardiovascular effects of oxytocin in animalmodels and women undergoing Caesarean section include tachycardia,hypotension and decrease in cardiac output. These can be sufficientto cause significant compromise in high-risk patients. We aimedto find a simple way to decrease these risks whilst retainingthe benefits of oxytocin in decreasing bleeding after delivery. Method. We recruited 30 women undergoing elective Caesareansection. They were randomly allocated to receive 5 u of oxytocineither as a bolus injection (bolus group) or an infusion over5 min (infusion group). These women had their heart rate andintra-arterial blood pressure recorded every 5 s throughoutthe procedure. The haemodynamic data, along with the estimatedblood loss, were compared between the groups. Results. Marked cardiovascular changes occurred in the bolusgroup; the heart rate increased by 17 (10.7) beats min^–1[mean (SD)] compared with 10 (9.7) beats min^–1 in theinfusion group. The mean arterial pressure decreased by 27 (7.6)mm Hg in the bolus group compared with 8 (8.7) mm Hg in theinfusion group. There were no differences in the estimated bloodloss between the two groups. Conclusion. We recommend that bolus doses should be used withcaution, and further studies should ascertain if oxytocin isequally effective in reducing blood loss when given at a slowerrate.     

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.     

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     

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.     

Dextromethorphan and intrathecal morphine for analgesia after Caesarean section under spinal anaesthesia

Background. Dextromethorphan is an N-methyl-D-aspartic acidantagonist which can attenuate acute pain with few side-effects.In this prospective, randomized, double-blind study of dextromethorphanand intrathecal morphine, we investigated postoperative pain,pruritus, nausea and vomiting in women undergoing Caesareansection under spinal anaesthesia. Methods. Women were allocated randomly to one of six groups,to receive intrathecal morphine 0.05, 0.1 or 0.2 mg plusoral dextromethorphan 60 mg or placebo. Results. The addition of dextromethorphan did not reduce postoperativepain scores (P=0.83). Compared with women receiving intrathecalmorphine 0.05 mg, women receiving higher doses had a significantlyhigher incidence of nausea and vomiting [odds ratio for intrathecalmorphine 0.1 mg, 4.0 (95% confidence interval 1.2–14.1);for intrathecal morphine 0.2 mg, 7.9 (2.3–27.1)].Compared with women receiving intrathecal morphine 0.05 mg,women receiving higher doses also had a significantly higherincidence of pruritus [odds ratio for intrathecal morphine 0.1 mg,3.2 (95% confidence interval 1.3–8.2); for intrathecalmorphine 0.2 mg, 3.7 (1.4–9.5)]. Women receivingdextromethorphan had a lower incidence of nausea and vomiting[odds ratio 2.6 (1.1–6.3)]. Conclusions. Postoperative pain after Caesarean section underspinal anaesthesia was not reduced by the addition of oral dextromethorphanto a multimodal approach including intrathecal morphine. Br J Anaesth 2003; 90: 653–8     

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     

Anaesthetic management of a parturient with pulmonary stenosis and aortic incompetence for Caesarean section

Anaesthetic management of Caesarean section in a parturientwith severe pulmonary stenosis and aortic regurgitation is described.The valvular sequelae resulted from previous unsuccessful surgicalcorrection (Ross procedure) of congenital aortic stenosis. Thiscase demonstrates the importance of multi-disciplinary assessmentand careful anaesthetic planning, to avoid deterioration inperioperative cardiac performance in parturients with complexvalvular disease. Br J Anaesth 2003; 90: 241–3     

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.     

Comparison of the effects of intrathecal ropivacaine, levobupivacaine, and bupivacaine for Caesarean section

Background. This study aimed to detect if intrathecal (i.t.)ropivacaine and levobupivacaine provided anaesthesia (satisfactoryanalgesia and muscular relaxation) and postoperative analgesiaof similar quality to bupivacaine in patients undergoing Caesareansection. Methods. Ninety parturients were enrolled. A combined spinal-epiduraltechnique was used. Patients were randomly assigned to receiveone of the following isobaric i.t. solutions: bupivacaine 8mg (n=30), levobupivacaine 8 mg (n=30), or ropivacaine 12 mg(n=30), all combined with sufentanil 2.5 µg. An i.t. solutionwas considered effective if an upper sensory level to pinprickof T4 or above was achieved and if intraoperative epidural supplementationwas not required. Sensory changes and motor changes were recorded. Results. Anaesthesia was effective in 97, 80, and 87% of patientsin the bupivacaine 8 mg, levobupivacaine 8 mg, and ropivacaine12 mg groups, respectively. Bupivacaine 8 mg was associatedwith a significantly superior success rate to that observedin the levobupivacaine group (P<0.05). It also provided alonger duration of analgesia and motor block (P<0.05 vs levobupivacaineand ropivacaine). Conclusions. The racemic mixture of bupivacaine combined withsufentanil remains an appropriate choice when performing Caesareansections under spinal anaesthesia. Br J Anaesth 2003; 91: 684–9     

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.     

Spread of subarachnoid block, intraoperative local anaesthetic requirements and postoperative analgesic requirements in Caesarean section and total abdominal hysterectomy

Background. Pregnancy is associated with a higher spread ofsubarachnoid anaesthesia and increased pain threshold. The studywas designed to assess the spread of subarachnoid block andthe intra- and postoperative analgesic requirements in pregnantvs non-pregnant women. Methods. We assessed the level of subarachnoid anaesthesia after1.8 ml of hyperbaric lidocaine 5% and the postoperative analgesicrequirements in women undergoing Caesarean section and undergoingabdominal hysterectomy (30 each group). Intraoperatively epiduralropivacaine was given as required. All patients received 10ml of ropivacaine 0.2% epidurally 2, 10, and 24 h after operationand the VAS pain score was assessed. They also had access topatient controlled analgesia i.v. morphine. Results. Duration of surgery was 64 (13.7) vs 127 (33.8) min(P<0.0001) in the pregnant and non-pregnant groups. Ten minutesafter subarachnoid injection, sensory block was higher by threedermatomes in the pregnant group (P<0.0001). Time to firstropivacaine dose was 37 (19.7) vs 19 (12.2) min (P<0.001)and the ropivacaine normalized for the duration of anaesthesiawas 0.8 (0.6) vs 1.3 (0.5) mg^–1 (P=0.001) in the pregnantand non-pregnant groups, respectively. The time between thefirst and second ropivacaine dose was similar in the two groups(P=0.070). Fewer pregnant women (81 vs 100%) required ropivacaineintraoperatively (P=0.017). The VAS scores were similar butparturients consumed more i.v. morphine (33 (14) vs 24 (12)mg, P=0.016) during the first 24 h after operation. Conclusions. Pregnant patients exhibited a higher level of subarachnoidsensory block and required more i.v. morphine after operation.