Intrathecal catheter use after accidental dural puncture in obstetric patients: literature review and clinical management recommendations

If an accidental dural puncture occurs, one option is to insert a catheter and use it as an intrathecal catheter. This avoids the need for a further injection and can rapidly provide labour analgesia and anaesthesia for caesarean section. However, there are no recommendations for managing intrathecal catheters and, therefore, significant variation in clinical practice exists. Mismanagement of the intrathecal catheter can lead to increased motor block, high spinal anaesthesia, drug error, hypotension and fetal bradycardia. Care must be taken with an intrathecal catheter to adhere to strict aseptic technique, meticulous labelling, cautious administration of medications and good communication with the patient and other staff. Every institution considering the use of intrathecal catheters should establish a protocol. For labour analgesia, we recommend the use of dilute local anaesthetic agents and opioids. For caesarean section anaesthesia, gradual titration to the level of the fourth thoracic dermatome, with full monitoring, in a facility equipped to manage complications, should be performed using local anaesthetics combined with lipophilic opioids and morphine or diamorphine. Although evidence of the presence and duration of intrathecal catheters on the development of post-dural puncture headache and need for epidural blood patch is limited, we suggest considering leaving the intrathecal catheter in for 24 hours to reduce the chance of developing a post-dural puncture headache while maintaining precautions to avoid drug error and cerebrospinal fluid leakage. Injection of sterile normal saline into the intrathecal catheter may reduce post-dural puncture headache. The level of evidence for these recommendations was low.

A randomized comparison of automated intermittent mandatory boluses with a basal infusion in combination with patient-controlled epidural analgesia for labor and delivery

BACKGROUND

Automated mandatory boluses (AMB), when used in place of a continuous basal infusion, have been shown to reduce overall local anesthetic consumption without compromising analgesic efficacy in patient-controlled epidural analgesia (PCEA). We hypothesized that our PCEA+AMB regimen could result in a reduction of breakthrough pain requiring epidural supplementation in comparison with PCEA with a basal infusion (PCEA+BI).

METHODS

We recruited sixty-two healthy ASA I nulliparous parturients in early labor. The parturients were randomized to receive 0.1% ropivacaine+fentanyl 2 μg/mL either via PCEA+BI (PCEA with basal continuous infusion of 5mL/h) or PCEA+AMB (PCEA with AMB of 5 mL every hour instead of a basal infusion) immediately following successful induction of combined spinal-epidural (CSE) analgesia. Block characteristics, incidence of breakthrough pain requiring epidural supplementation, side effects, obstetric outcomes, Apgar scores and overall maternal satisfaction with analgesia were noted.

RESULTS

The time-weighted hourly consumption of ropivacaine (PCEA and clinician supplementation for breakthrough pain) was significantly lower in the PCEA+AMB group (mean=7.6 mL, SD 3.2) compared to the PCEA+BI group (mean=9.3 mL, SD 2.5; P<0.001). The mean time to first PCEA self-bolus following CSE was significantly longer in the PCEA+AMB group compared to the PCEA+BI group (268 min vs. 104 min; P<0.001). Parturients in Group PCEA+AMB also gave higher satisfaction scores. The incidence of breakthrough pain was similar in both groups.

CONCLUSION

PCEA+AMB, when compared to PCEA+BI, confers greater patient satisfaction and a longer duration of effective analgesia after CSE despite reduced analgesic consumption.

Comparison of Automated Intermittent Low Volume Bolus with Continuous Infusion for Labour Epidural Analgesia

Delivery of local anaesthetics via automated intermittent bolus has been shown to improve epidural analgesia compared to delivery via continuous epidural infusion. However, the optimal bolus volume has not been investigated. This randomised, double-blind study compared the analgesic efficacy of automated intermittent bolus (volume 2.5 ml every 15 minutes) with that of a continuous epidural infusion (10 ml/hour) for the maintenance of labour epidural analgesia, to determine whether the advantages previously demonstrated for automated intermittent bolus over continuous epidural infusion are retained at this low bolus volume. With the approval of the Hospital Ethics Committee, we recruited 50 parturients who received combined spinal epidural analgesia with intrathecal ropivacaine 2 mg and fentanyl 15 μg. For epidural maintenance, participants were randomised to either the automated intermittent bolus group (2.5 ml automated intermittent epidural boluses of ropivacaine 0.1% plus fentanyl 2 μg/ml delivered over a two-minute period every 15 minutes) or the continuous epidural infusion group (continuous epidural infusion of ropivacaine 0.1% plus fentanyl 2 μg/ml at 10 ml/hour). The primary study outcome was the incidence of pain during labour that required management with supplemental epidural analgesia. There were no significant differences between the two regimens in terms of breakthrough pain (automated intermittent bolus 36% [9/25] vs continuous epidural infusion 32% [8/25], P=0.77). At the doses used in this study, maintenance of labour analgesia using automated intermittent bolus at a bolus volume of 2.5 ml every 15 minutes does not decrease the incidence of breakthrough pain or improve analgesic efficacy compared to continuous epidural infusion.

Advances in neuraxial blocks for labor analgesia: new techniques, new systems

Neuraxial block for labor analgesia is widely accepted and highly effective. Much progress has been achieved in terms of providing safer and more efficacious analgesia. Emphasis has been placed on maternal autonomy and individualization of therapy. The introduction of the combined spinal-epidural technique in the labor ward has afforded excellent rapid onset analgesia and minimal impediment to maternal mobility. Newer enantiopure amide local anesthetics, like ropivacaine and levobupivacaine, have also been introduced to enhance the safety of epidural analgesia with respect to cardiotoxicity. The introduction of the computer-assisted approach to provide a more interactive background infusion could potentially refine the delivery of patient-controlled epidural analgesia. The enhanced effectiveness of synchronized basal automated boluses has also been exploited for patient-controlled epidural analgesic systems. The quest to provide seamless analgesia that empowers the laboring parturient in a cost effective way continues to be a developing area of research.

Computer-integrated patient-controlled epidural analgesia: a preliminary study on a novel approach of providing pain relief in labour

INTRODUCTION

The need for individualisation of analgesic therapy in labour cannot be overemphasised. We have devised a programme, based on a novel clinical algorithm, that converts a continuous infusion pump into a patient-controlled epidural analgesia (PCEA) pump that is responsive to the patient's needs by varying its rate of infusion.

METHODS

In this double-blinded, controlled trial, 40 American Society of Anesthesiologists 1 patients were recruited to receive either a continuous infusion of 10 ml/hour (Continuous Epidural Infusion [CEI], n=20) or the computer-integrated (CI) regimen (CI-PCEA, n=20) to maintain epidural analgesia after successful induction of combined spinal analgesia during early labour. The proportion of patients who had delivered without a requirement for analgesic supplementation was the primary outcome measure.

RESULTS

There was a significant difference in the incidence of breakthrough pain, i.e. the primary outcome measure (two in CI-PCEA versus eight in the CEI group, p-value is 0.027). There was a trend towards a longer duration before analgesic supplementation of analgesia was required after its induction with CI-PCEA than CEI (p-value is 0.06). We could not detect a difference in the total hourly consumption of epidural analgesics between the two groups.

CONCLUSION

Our study also showed that with the CI-PCEA programme, we were able to convert an ordinary infusion pump to one which analyses the patients' needs in the previous hour (based on analgesic demands) and automatically adjusts the basal infusion accordingly. CI-PCEA reduced the incidence of breakthrough pain without the evidence of increasing drug consumption when compared with CEI.

Comparison of computer integrated patient controlled epidural analgesia vs. conventional patient controlled epidural analgesia for pain relief in labour

Computer integrated-patient controlled epidural analgesia (CI-PCEA) is a novel drug delivery system. It automatically titrates the background infusion rate based on the individual parturient's need. In this randomised trial, we compared the local anaesthetic consumption by parturients using CI-PCEA with demand only patient controlled epidural analgesia (PCEA) for labour analgesia. We recruited 40 parturients after approval by the ethics committee. Group PCEA (n = 20) received demand only PCEA. Group CI-PCEA (n = 20) received a similar PCEA regimen but the computer integration titrated the background infusion to 5, 10 or 15 ml x h(-1) if the patient required one, two or three demand boluses, respectively, in the previous hour. The background infusion decreased by 5 ml x h(-1) if there was no demand bolus in the previous hour. The sample size was calculated to show equivalence in local anaesthetic used. The time weighted consumption of local anaesthetic was similar in both groups (mean difference 0.7 mg x h(-1), 95% confidence interval [CI: -2.5, 1.1]; p = 0.425). The CI-PCEA group had higher maternal satisfaction scores: mean (SD) 93 (7) vs. 86 (11), p = 0.042. CI-PCEA does not increase the use of local anaesthetic when compared with demand only PCEA but does increase patient satisfaction.

Morphine for post-caesarean section analgesia: intrathecal, epidural or intravenous?

INTRODUCTION

Good analgesia is important after a caesarean section but there are no studies to date that compared intrathecal (IT), epidural (EP) and intravenous patient-controlled analgesia (IV PCA) morphine for post-caesarean section analgesia. In this study, we compared the differences in the quality of analgesia and side effects rendered by IT, EP and IV PCA morphine for post-caesarean section analgesia.

METHODS

We systematically collected and reviewed the data of 949 women who received IT, EP or IV PCA morphine for post-caesarean analgesia during a six-month period. We reviewed the patients 24 hours after surgery and recorded the type of analgesia, the use of adjuncts, pain scores, side effects and degree of satisfaction with the mode of analgesia. The data was captured in an electronic database and analysed.

RESULTS

IT morphine was the predominant method of post-caesarean analgesia, accounting for 89.5 percent of the cases. Non-steroidal anti-inflammatory drugs (NSAIDs) were more commonly used in the IT and EP group (IT 76 percent, EP 80 percent and IV PCA 49 percent, p-value is less than 0.05). IT morphine group had a significantly lower pain score at rest (p-value is less than 0.001) and on movement (p-value is less than 0.05) when compared with IV PCA group. EP morphine also resulted in a lower pain score than IV PCA on movement (p-value is less than 0.05). There was no difference in pain scores between EP and IT morphine. In the subgroup analysis of patients who did not receive NSAIDs, IT and EP morphine group also registered lower pain scores at rest and on movement than IV PCA group (p-value is less than 0.05). There was no difference in the satisfaction scores among the three groups.

CONCLUSION

The use of IT and EP morphine was associated with lower pain scores than IV PCA morphine at rest and on movement in the first 24 hours after caesarean section. No severe side effects were found.

The in vitro effects of clonidine and dexmedetomidine on human myometrium

BACKGROUND

alpha(2)-adrenergic agonists have been used extensively in the field of anaesthesia. Their direct effect on the human myometrium was investigated in this in vitro study, as this may have clinical repercussions in obstetric anaesthesia.

METHOD

Strips of pregnant human myometrium obtained from six individuals at elective caesarean section were mounted on the Mulvany myograph in Krebs solution to which increasing concentrations of clonidine and dexmedetomidine (1x10(-11) to 1x10(-6) g/mL) were added.

RESULTS

Dexmedetomidine increased uterine contractility at simulated clinical plasma concentrations (1x10(-9) g/mL). These effects were seen with clonidine only at much higher tissue bath concentrations (1x10(-7) g/mL).

CONCLUSION

The effect of dexmedetomidine on human myometrium has profound implications in obstetric anaesthesia and needs further clinical investigation.

Neuraxial block for labour analgesia--is the combined spinal epidural (CSE) modality a good alternative to conventional epidural analgesia?

AIM

Apart from conventional epidural analgesia (EA), the combined spinal-epidural (CSE) modality is fast becoming a popular technique for treating labour pain. In this study, we investigated the differences in the patient profile and outcome between CSE and EA for labour pain in KK Women's and Children's Hospital.

METHODOLOGY

Data pertaining to 1,532 healthy parturients who had received either CSE or EA for labour pain during a six-month period was systematically collected by using a specially designed form. Multiple logistic regression analysis was used to determine the independent predictors of patient satisfaction and the relation of parturient factors on the choice of block. The side effects and the outcome of labour were also compared.

RESULTS

CSE accounted for 80% of all neuraxial blocks performed for labour analgesia (vs 20% for EA). Anaesthesiologists were more inclined to using CSE than EA for multiparous parturients (OR 2.03, p<0.01) in a more painful (OR=1.61, p=0.03) and advanced stage of labour (OR=1.12, p=0.03). The need for supplemental analgesics was greater for EA (p<0.01). Patient satisfaction was higher for CSE (OR=1.77, p<0.026). CSE had a higher risk of pruritus (29% vs 14%, p<0.01) but lower risk of post block neural deficits (0% vs 2%, p<0.01) than EA. No difference in the mode of delivery was detected between the two groups.

CONCLUSION

CSE is a safe and good alternative to EA as a technique of neuraxial block for labour analgesia.

Parturient-controlled epidural analgesia during labour: bupivacaine vs. ropivacaine

In this randomised, controlled study, we compared the hourly dose requirement of ropivacaine 0.125% (group R, n = 16) with bupivacaine 0.125% (group B, n = 16) provided by demand-only (bolus 5 ml, lockout 10 min) parturient-controlled epidural analgesia during labour. The hourly dose requirement was comparable although group R had a lower successful to total demands ratio (p < 0.05). We also found that both groups were clinically indistinguishable in terms of pain relief and side-effects. No difference in maternal or fetal outcome was detected. We conclude that, at a concentration of 0.125%, ropivacaine and bupivacaine were equally effective when self-administered using this patient-controlled regimen.

Either sufentanil or fentanyl, in addition to intrathecal bupivacaine, provide satisfactory early labour analgesia

PURPOSE

The study was aimed primarily at comparing the duration of analgesia produced by intrathecal fentanyl 25 microg with sufentanil 5 microg when added to bupivacaine 1.25 mg as the initial component of the combined spinal epidural (CSE) technique in early labour.

METHODS

Forty healthy parturients were randomly assigned into two groups to receive either intrathecal sufentanil 5 microg plus bupivacaine 1.25 mg (Group S) or intrathecal fentanyl 25 microg plus bupivacaine 1.25 mg (Group F). Apart from the duration of analgesia, pain scores and side effects were also evaluated.

RESULTS

There was no significant difference in the duration of analgesia (mean 109 +/- SD 49 min in Group F vs 118 +/- 54 min in Group S, P=0.9). Group F had a more rapid onset of analgesia (P <0.05) and a higher cephalad block (median T4 vs T7, P <0.05) in the first 30 min after the block. No difference in the side effects was detected.

CONCLUSION

Fentanyl 25 microg is a good alternative to sufentanil 5 microg when added to bupivacaine 1.25 mg for early labour analgesia.

The effect of the addition of ropivacaine or bupivacaine upon pruritus induced by intrathecal fentanyl in labour

Sixty patients in early labour were randomly allocated to one of three groups. The control group received intrathecal fentanyl 25 microg, the ropivacaine group received intrathecal fentanyl 25 microg and ropivacaine 2.5 mg while the bupivacaine group received intrathecal fentanyl 25 microg and bupivacaine 2.5 mg. The incidence of pruritus was 100% in controls, compared with 85% in the ropivacaine group (not significant) and 75% in the bupivacaine group (p = 0.003). The severity of pruritus was significantly less in the ropivacaine (p = 0.006) and bupivacaine (p = 0.001) groups. Most patients developed pruritus by 30 min. Pruritus above the abdomen was not reduced in patients receiving local anaesthetics. There were no significant differences in the mean pain visual analogue score, systolic blood pressure, maternal heart rate and upper level of reduced pin-prick sensation in the first 30 min. Intrathecal ropivacaine and, more so, intrathecal bupivacaine reduce the incidence and severity of pruritus from intrathecal fentanyl for labour analgesia.

The effect of adding fentanyl to ropivacaine 0.125% on patient-controlled epidural analgesia during labour

The use of patient-controlled epidural analgesia (PCEA) for labour analgesia is rapidly gaining acceptance. However, the ideal PCEA solution and PCEA program remains uncertain. We studied the effect of adding fentanyl 2 micrograms/ml on demand-only PCEA using ropivacaine 0.125% for labour analgesia. With the approval of the Hospital Ethics Committee, this prospective randomized controlled trial was conducted on 36 nulliparous ASA 1/2 parturients in early, but established, labour. Upon written consent, epidural analgesia was started with 10 ml ropivacaine 0.2%. The parturients subsequently were randomized to receive either ropivacaine 0.125% (n = 18) or ropivacaine 0.125% with fentanyl 2 micrograms/ml (n = 18). The PCEA was programmed to a demand-only mode with bolus of 5 ml, lockout time of 10 minutes and maximum volume per hour of 20 ml. The degree of pain relief was similar in both groups. However, the total amount of ropivacaine used per hour was lower in the group that received fentanyl (median 7.1 vs 10.1 mg, P < 0.05). This was not associated with a decrease in motor blockade or a decrease in instrumental deliveries. The ratio of successful PCEA demand to total number of demands, the satisfaction score and the maternal-fetal outcome were similar in both groups. In conclusion, the addition of fentanyl had a dose-sparing effect on the requirement of ropivacaine. This PCEA regimen produced a low incidence of motor block, good labour pain relief and excellent patient satisfaction.

Optimal dose of intrathecal clonidine added to sufentanil plus bupivacaine for labour analgesia

PURPOSE

The combination of intrathecal (IT) 5 microg sufentanil plus 1.25 mg bupivacaine is useful for inducing labour analgesia, albeit of short duration and slow onset. As a supplementation to this regimen, the effect of IT clonidine on the duration of analgesic action was investigated.

METHODS

Forty-eight healthy parturients were randomly assigned into three groups to receive 0 microg (group C0), 15 microg (C15) or 30 microg (C30) of clonidine IT in addition to 5 microg sufentanil plus 1.25 mg bupivacaine IT for labour analgesia. The quality of pain relief was assessed on 0-100 visual analogue scale by the author. The occurrence of side effects was also evaluated before the request for additional analgesia.

RESULTS

Clonidine (C15 and C30), produced a longer duration of analgesia than C0 (mean 144 +/- sd 27.9, 165 +/- 31.8 vs 111 +/- 21.9 min, P < 0.01). Also, C15 and C30 produced a more rapid onset and a higher quality of analgesia than C0, (P < 0.01). The most cephalad level of sensory block was higher in C30 than C15 (median T3 vs T4, P < 0.05) but lowest in C0 (median T7 vs T3,T4, P < 0.01). Side effects, sedation and hypotension, occurred more frequently in C30 than in either C0 or C 15, (9 vs 2,5 and 9 vs 1,3, respectively, P < 0.05).

CONCLUSION

The optimal dose of intrathecal clonidine to enhance labour analgesia with the current sufentanil-bupivacaine regimen is 15 microg. In view of the side effect profile, doses greater than 30 microg clonidine are unlikely to be useful.

A comparison of patient-controlled epidural analgesia following gynaecological surgery with and without a background infusion

We conducted a randomised, controlled study to investigate the effect of adding a background infusion to patient-controlled epidural analgesia for postoperative pain relief. Forty-two patients scheduled for elective lower abdominal gynaecological surgery received patient-controlled epidural analgesia postoperatively using a mixture of 0.2% ropivacaine and 2.0 microg x ml-1 fentanyl. Patients in group B (n = 20) were given a background infusion of 5 ml x h-1, whereas those in group N (n = 21) were not. There was no difference in pain scores or patient satisfaction scores between the two groups. Patients in group B had a higher total drug consumption (156.8 +/- 34.8 ml vs. 89.5 +/- 41.0 ml; p < 0.0001) and incidence of side-effects (71.4% vs. 30.0%; p = 0.007). Motor blockade during the 24-h study period was also greater in group B (median [range] area under the curve 7.5 [0.0-39.0] h vs. 3.0 [0.0-36.0] h; p = 0.035). We conclude that the addition of a background infusion to patient-controlled epidural anaesthesia is not recommended as it confers no additional benefits.

Motor blockade is reduced with ropivacaine 0.125% for parturient-controlled epidural analgesia during labour

PURPOSE

To compare the effect on the incidence of motor block by reducing the concentration of ropivacaine from 0.2% to 0.125% in parturient-controlled epidural analgesia (PCEA) for labour.

METHODS

Randomized, controlled and double-blind trial involving parturients in early labour who received demand-only PCEA regimen (bolus 5 ml, lockout 10 min, maximum volume per hour of 20 ml) with either 0.2% (R0.2 group, n = 25) or 0.125% (R0.125 group, n = 25) ropivacaine. Pain scores, the degree of motor block, the rate of drug consumption, the proportion of good to total PCEA demands and the overall satisfaction scores were documented.

RESULTS

Fewer parturients in the R0.125 group had lower limb motor block (4 vs. 11, P<0.05) although the degree of block was mild in all the affected parturients. The ratio of good to total PCEA demands was more favourable in the R0.2% group (median 0.72 vs. 0.52, P<0.01) although the hourly rate of ropivacaine consumption, the degree of pain relief, the maternal-fetal outcome and the overall satisfaction scores were similar.

CONCLUSION

Both ropivacaine 0.2% and 0.125% provided comparably effective analgesia but motor block occurred more commonly in the 0.2% group.

Epidural 0.2% ropivacaine for labour analgesia: parturient-controlled or continuous infusion?

In this randomized, open study, we compared the incidence of lower limb motor block associated with epidural labour analgesia provided by parturient-controlled method (PCEA) with continuous infusion (CIEA) using 0.2% ropivacaine. The PCEA group (n = 20) received a demand-only regimen (bolus 5 ml, lockout 15 minutes). The rate of infusion of the CIEA group (n = 20) was 8 ml/h. We found that pain relief was not significantly different between the two groups, although the PCEA group had a higher satisfaction score (P < 0.05). Fewer parturients in the PCEA group had lower limb motor block (6 vs 14, P < 0.05). The total volume of ropivacaine used per hour was also lower in the PCEA group (median 8.75 vs 10.5 ml, P < 0.05). No difference in the maternal or fetal outcome was detected. We conclude that PCEA with ropivacaine is an effective mode of analgesia which is dose-sparing and produces less motor block in comparison with CIEA.

Combination of intrathecal sufentanil 10 mug plus bupivacaine 2.5 mg for labor analgesia: is half the dose enough?

This controlled, double-blinded, prospective trial of 42 parturients in early labor was conducted to determine whether halving the total amount of intrathecal (i.t.) sufentanil and bupivacaine reduced the incidence of systemic hypotension while providing adequate analgesia with minimal lower limb motor block. Combined spinal-epidural analgesia (CSE) was instituted; Group A (n = 21) received a total of 10 microg of sulfentanil plus 2.5 mg of bupivacaine, whereas Group B (n = 21) received half that dose. Compared with Group B, Group A had a higher incidence of hypotension (nine parturients in Group A, two in Group B; P < 0.05), a greater degree of motor block (P < 0.05), and a higher incidence of sedation (nine parturients in Group A were sedated, one in Group B; P < 0.01). Group B had higher pain scores for the first 5 min (P < 0.05) and a lower level of sensory blockade (median of T7 in Group B compared with T4 in Group A; P < 0.01). We conclude that halving the total amount of i.t. 10 microg of sufentanil plus 2.5 mg of bupivacaine is a suitable option for CSE in labor because it reduces the incidence of some side effects, such as hypotension and maternal sedation, without compromising overall high maternal satisfaction.

IMPLICATIONS

We showed that adequate labor pain relief could be provided by halving the recommended dose of 10 microg of intrathecal sufentanil plus 2.5 mg of bupivacaine. The larger dose, however, produced faster pain relief, which lasted longer than the reduced dose. The mother and baby were not adversely affected with either dose.

Intrathecal sufentanil as the sole agent in combined spinal-epidural analgesia for the ambulatory parturient

PURPOSE

To compare the effect of a combination of intrathecal (i.t.) sufentanil plus bupivacaine with i.t. sufentanil alone, on the incidence of hypotension and the success of ambulation in parturients.

METHODS

This was a controlled, double-blind prospective trial involving 50 parturients in early labour who had received combined spinal-epidural analgesia (CSE). They were divided equally into two groups; group A received 10 micrograms i.t. sufentanil while group B received i.t. 10 micrograms sufentanil plus 2.5 mg plain bupivacaine. The blood pressure, pain scores, the highest sensory block and the degree of motor blockade were documented over the first 30 min by an unbiased anaesthetist. The ability and the desire to ambulate was studied 30 min after CSE. The side effects were documented throughout labour.

RESULTS

Group B had a higher incidence of hypotension; (12 vs 3: P < 0.01). Fewer parturients in group B could ambulate (19 vs 25: P < 0.05). Group B also had a higher sensory blockade than group A (median T4 VS T7-8: P < 0.01). Of all the 44 parturients who could ambulate, 13 desired not to do so, usually due to sedation.

CONCLUSION

The quality of analgesia in all subjects in the study was excellent. Side effects were more common in the i.t. sufentanil-bupivacaine combination group.

Severe mitral stenosis in a parturient with congestive cardiac failure and hypoglycaemia

We report a case of maternal mortality in a 34-year-old multipara who presented at the 35th week of gestation with severe hypoglycaemia. She had no history of diabetes mellitus. This episode was a prelude to catastrophic and refractory congestive cardiac failure due to previously undiagnosed severe mitral stenosis. The rapid cardiovascular deterioration initially appeared to be consistent with amniotic fluid embolism. She also developed deranged liver function with disseminated intravascular coagulation, which mimicked acute fatty liver of pregnancy. The problems of diagnosis and management are discussed. Unfortunately the patient died before mitral valvular commissurotomy could be effected.

Alkalinization of lidocaine does not hasten the onset of axillary brachial plexus block

We assessed the onset of sensory and motor blockade as well as the distribution of sensory blockade after axillary brachial plexus block with 1.5% lidocaine hydrochloride 1:200,000 epinephrine with and without sodium bicarbonate in 38 patients. The onset of analgesia and anesthesia was recorded over the distributions of the median, ulnar, radial, and medial cutaneous nerves of the forearm, medial cutaneous and lateral cutaneous nerves of the arm, and musculocutaneous nerve. The onset of motor blockade of elbow and wrist movements was also recorded. Data were analyzed by using survival techniques and compared by using log rank tests. Only the onset of analgesia in the medial cutaneous nerves of the arm and forearm, and the onset of anesthesia in the medial cutaneous nerve of the arm were significantly faster (P < 0.05) with alkalinization of lidocaine. Our study showed that alkalinization of lidocaine does not significantly hasten block onset in most terminal nerve distributions.

IMPLICATIONS

We examined whether alkalinizing a local anesthetic would quicken the onset of a regional upper limb nerve blockade. We found that alkalinization of lidocaine did not offer a significant clinical advantage in axillary brachial plexus blockade.

A preliminary report on anaesthesia for thoracoscopic oesophagectomy

The anaesthetic experience in three patients undergoing thoracoscopic oesophagectomy is discussed. The indications for surgery and the premorbid states are outlined. The necessity for one-lung ventilation, with its attendant cardiopulmonary effects, the difficulty of patient access and the assessment of blood loss were the main problems encountered. Pulmonary morbidity was high in the post-operative period despite the avoidance of thoracotomy. Two patients developed persistent vocal cord paralysis. In conclusion, the role of thoracoscopic oesophagectomy needs further evaluation.

Intrathecal pethidine: an alternative anaesthetic for transurethral resection of prostate?

We aimed to determine the usefulness of intrathecal pethidine as the sole anaesthetic for transurethral resection of prostate (TURP) while comparing the incidence of hypotension with intrathecal bupivacaine. A double-binded randomized prospective trial was conducted involving 40 patients for TURP. The patients were divided equally into two groups; group A received 2 ml 0.5% bupivacaine intrathecally and group B received 40 mg pethidine intrathecally. Changes in blood pressure and heart rate were measured over the first 30 minutes. The highest sensory block and the time to reach it were documented. The degree of motor blockade was also recorded. There was no significant difference in the incidence of hypotension. The pethidine group had significantly greater reduction in heart rate, a lower degree of motor block, shorter period before requests for postoperative analgesia but a higher incidence of sedation, nausea and vomiting. Intrathecal pethidine did not offer any advantage over intrathecal bupivacaine for TURP.

Combination of suppository diclofenac and intravenous morphine infusion in post-caesarean section pain relief--a step towards balanced analgesia?

Post-Caesarean section analgesia can be achieved by morphine infusion. NSAIDs are frequently administered to relieve uterine cramps. This study is aimed at assessing the efficacy of the combination of suppository diclofenac and morphine infusion in post-Caesarean section pain relief. General anaesthesia was given to 60 patients who were randomly allocated into two groups: group A received 100 mg suppository diclofenac before surgical incision and morphine infusion 1.5 mg per hour postoperatively while group B received only morphine infusion 1.5 mg/H postoperatively. Pain assessment was done by an unbiased observer on arrival of the patients in the recovery room, then 6 hours, 12 hours and 24 hours later. Pain relief was found to be better in group A, with group B requiring more supplemental analgesia. Apart from better analgesic effect for wound pain, group A also had more favourable scores for uterine cramping pain. The incidence of nausea or vomiting was similar in both groups. No respiratory depression was observed in both groups. Two cases of increased bleeding (one from each group) were observed, both receiving conservative treatment.

THE CONCLUSION

suppository diclofenac improved the analgesic efficacy of morphine infusion in post-Caesarean analgesia.

Cardiac tamponade--an unlikely cause of unexplained hypotension in an isolated "minor" blunt chest injury

Cardiac tamponade after a minor blunt chest trauma is indeed rare. Here, we report on one such case presenting with unexplained hypotension at the Emergency Department. The problems of diagnosis and treatment are discussed. In short, the proper management of this life-threatening condition can only be rendered by a high index of suspicion and close vigilance.