Venous emboli occurring during Caesarean section: the effect of patient position

The effect of position, horizontal versus 5 degrees reverse Trendelenburg's, on the incidence of venous emboli during Caesarean section was evaluated in 207 patients. Venous emboli were diagnosed using precordial ultrasonic Doppler monitoring. In the horizontal position, 44% (60 of 134) parturients had venous emboli compared with 1% (1 of 73) parturients in the 5 degrees reverse Trendelenburg's position (P less than 0.0001). Epidural anaesthesia was performed in 171 patients, and 36 patients had general anaesthesia. In the epidural group, pulse oximetric haemoglobin oxygen desaturation and complaints of chest pain and/or dyspnoea were associated with the venous emboli. Venous emboli, probably air, occur frequently during Caesarean section with the patient in the horizontal position. This occurrence was minimized by placing the patient in the 5 degrees reverse Trendelenburg's position.     

Epidural morphine for analgesia after Caesarean section: a report of 4880 patients

This retrospective study was undertaken to assess the efficacy and safety of epidural morphine in providing analgesia following Caesarean section under epidural anaesthesia. The morphine was administered as a single bolus, following delivery, in doses ranging from 2 to 5 mg. The charts of 4880 Caesarean sections, performed on 4500 patients, were reviewed. The duration of analgesia and the occurrence of any symptoms which might be side-effects of the epidural morphine were recorded. The duration of analgesia was 22.9 +/- 10.1 hr and was not correlated with the dose of epidural morphine. Eleven per cent of the patients required no supplemental analgesia during the first 48 hr. Twelve patients (0.25 per cent) had respiratory rates less than 10 breaths per minute, on at least one occasion. No serious sequelae resulted from these periods of bradypnoea. Pruritus occurred in 58 per cent of patients, nausea and vomiting in 39.9 per cent and dizziness in ten per cent. Herpes simplex labialis was recorded in 3.5 per cent of patients. Epidural morphine is thus confirmed as an effective analgesic technique post-Caesarean section with 3 mg being the optimal dose. Even in this young healthy patient population, clinically detectable respiratory depression occurs so clinical respiratory monitoring is indicated.     

PLACENTAL BLOOD FLOW DURING CAESAREAN SECTION PERFORMED UNDER SUBARACHNOID BLOCKADE

Subarachnoid blockade using 0.5% bupivacine after a "preload"of Ringer's lactate solution 1500–2000 ml i.v. was studiedin nine patients undergoing elective Caesarean section. Ephedrineinfusion 50 mg in 500 ml was instituted at the first signs ofmaternal hypotension in seven patients. Although significantdecreases in mean maternal systolic, mean and diastolic arterialpressures were recorded, the individual decreases in pressurewere less than 30 mm Hg in all except two patients. In generalplacental blood flow did not change, although there was a markedincrease in one patient with toxaemia and a decrease in onewoman with diabetes mellitus. The babies were unaffected atdelivery. Preventive measures, especially the "preload" infusion,are important in the maintenance of adequate placental perfusionin patients undergoing Caesarean section under subarachnoidblockade.     

Arterial to end tidal carbon dioxide tension difference during Caesarean section anaesthesia

The relationship between arterial carbon dioxide tension and end tidal carbon dioxide tension was studied in 19 patients during general anaesthesia for Caesarean section. Thirteen patients scheduled for elective abdominal hysterectomy formed a nonpregnant group. There was significant correlation between arterial and end tidal CO2 tensions in both groups. During Caesarean section, this difference was significantly less than in the nonpregnant group.     

EFFECT OF ORAL OMEPRAZOLE ON INTRAGASTRIC pH AND VOLUME IN WOMEN UNDERGOING ELECTIVE CAESAREAN SECTION

We have studied in obstetric patients the efficacy of omeprazolein increasing intragastric pH to more than 2.5 and reducingvolume to less than 25 ml. Omeprazole 40 mg was given orallythe night before and again on the morning of surgery to 30 Asianwomen scheduled to undergo elective Caesarean section. Afterinduction of anaesthesia, a gastric tube was inserted and intragastriccontents aspirated. Volume and pH were recorded and measurementswere repeated on completion of surgery. The median (range) volumewas 2 (1–13) ml before surgery and 4 (0–14) ml atthe end of surgery. There was insufficient volume to measurepH in all patients. The median (range) pH was 6.7(4.6–7.4)before surgery in 20 patients and 6.6 (4.6–7.8) at theend of surgery in 28 patients. No adverse drug reactions werenoted in mothers or neonates. Omeprazole 40 mg orally twicebefore elective Caesarean section appeared to be effective inreducing intragastric volume and acidity to acceptable values.     

Chronic pain following Caesarean section

BACKGROUND: Chronic postoperative pain is a well-recognized problem after various types of surgery such as amputation, thoracotomy, mastectomy, gallbladder surgery and inguinal hernia repair. However, little is known about chronic pain after gynaecologic surgery. Therefore, the aim was to study the incidence of chronic pain after Caesarean section. METHODS: A questionnaire was sent in February/March 2003 to 244 consecutive patients who underwent Caesarean section in a one-year period from 1 October 2001 to 30 September 2002. Patients were asked about duration of postoperative abdominal scar pain, and if pain was still present to describe the frequency and intensity of pain and its impact on daily life. The questionnaire also included questions about the Caesarean section and about pain problems elsewhere. RESULTS: A total of 220 patients (90.2%) answered the questionnaire. The mean follow-up time was 10.2 months (range 6-17.6). Postoperative pain resolved in most patients within 3 months but 27 patients (12.3%) still had pain at the time of the interview. No patients had constant pain, but in 13 of 27 patients (5.9%) pain was present daily or almost daily. Patients with persistent pain (n = 27) had more often undergone general than spinal anaesthesia for the Caesarean section. Frequencies of pain problems elsewhere and recalls of severe acute postoperative pain were also higher among patients with persistent pain. CONCLUSION: Chronic pain after Caesarean section seems to be a significant problem in at least 5.9% of patients.     

Combination treatment with ranitidine and sodium bicarbonate prior to obstetric anaesthesia

The gastric pH and volume were measured in 175 patients undergoing elective, and 313 undergoing emergency, obstetric procedures. Ranitidine 150 mg was administered orally every 6 hours in labour and at least 2 hours before elective Caesarean section. Patients received 20 ml of 8.4% sodium bicarbonate orally immediately prior to induction of anaesthesia. The combination of ranitidine and sodium bicarbonate produced marked alkalinisation of gastric contents (mean pH 8.9). The administration of sodium bicarbonate pre-operatively in patients who received ranitidine less than 2 hours before operation led to satisfactory elevation of gastric pH. Only four patients had a gastric pH less than 2.5, one patient refused any medication, two received only ranitidine and one patient had a long interval from administration of bicarbonate to aspiration of gastric contents. Gastric volumes were high in labouring patients (mean 84 ml) despite administration of ranitidine. The effectiveness of sodium bicarbonate as a single dose antacid therapy prior to obstetric anaesthesia requires further study.     

Comparison of the 25-gauge Whitacre with the 24-gauge Sprotte spinal needle for elective Caesarean section: cost implications

Spinal anaesthesia provides rapid, safe anaesthesia for Caesarean section. The pencil-point spinal needles (Sprotte and Whitacre) are reported to have a low incidence of post-dural puncture headache (PDPH). As the 25G Whitacre is less expensive than the 24G Sprotte needle, this prospective, randomized, doubleblind study was designed to compare the incidence of PDPH and ease of insertion of these needles in 304 ASA 1 and 2 women having elective Caesarean section under spinal anaesthesia. Each patient was assessed daily for five consecutive days following Caesarean section by an investigator blinded to the needle used. The results indicate that the two needles have a similar ease of insertion, number of failed insertions, and failed subarachnoid blockade. An inability to insert the spinal needles occurred in two patients in each group. Therefore, 150 patients in each group completed the study. The incidence of PDPH with the 24G Sprotte needle was 4.0% (6/150) compared with 0.66% (1/150) with the 25G Whitacre (NS). There was no correlation between the occurrence of PDPH and the difficulty of needle insertion, presence of transient hypotension or the effectiveness of anaesthesia delivered. This study indicates that both needles are comparable with respect to ease of insertion and incidence of PDPH. As the Whitacre needle is less expensive it is a reasonable alternative to the more expensive Sprotte needle.     

高渗氯化钠-羟乙基淀粉用于子痫前期腰麻下剖宫产术的可行性

目的 研究子痫前期产妇在腰麻下行剖宫产术时输入高渗氯化钠-羟乙基淀粉液(HSH)对产妇及新生儿的安全性.方法 临床确诊子痫前期产妇30例随机分为观察组(n=20)和对照组(n=10).观察组先输注5 ml/kg HSH,再输注复方氯化钠;对照组仅输注复方氯化钠.抽取静脉血检测手术前后RBC、Hb、红细胞比容(Hct)、血小板计数(Plt)及电解质;记录术中MAP、HR、输液量、失血量、尿量和术后24 h内产妇进液量与出液量;记录麻黄碱的应用例数以及新生儿1 minApgar评分.结果 两组RBC、Hct、Plt和血清电解质手术前后及组间差异均无统计学意义;术中HR组内、组间比较差异亦无统计学意义;两组MAP在麻醉后5、8、10 min及术毕四个时点较麻醉前均明显降低(P＜0.05),且观察组MAP在麻醉后四个时点均高于对照组(P＜0.05);观察组术中输液量明显少于对照组,尿量多于对照组(P＜0.05);而术中失血量、术后24 h内输液量、尿量及新生儿.Apgar评分比较差异无统计学意义.结论 子痫前期产妇腰麻下行剖宫产术时输入5 ml/kg HSH是安全可行的.     

Epidural versus general anaesthesia for elective Caesarean section Effect on Apgar score and acid-base status of the newborn

Elective Caesarean section deliveries over a 5-year period were studied to compare the effect of epidural block with general anaesthesia on the condition of the infant at birth. The Apgar score and umbilical arterial acid-base status were used as determinants of the latter. Epidural block was used in 139 (22.8%) mothers while 471 (77.2%) were performed under general anaesthesia. No babies in the epidural group were severely depressed (Apgar less than 4), compared with 6.2% in the general anaesthesia group. Only 4.3% of the epidural sections were moderately depressed (Apgar 4-6), compared with 15.4% of the others. These differences remained highly significant when infants of less than 2500 g were excluded, and when matched groups were compared. Mean umbilical arterial pH was similar within the two groups (pH 7.28), and was not consistent with asphyxia in almost 90% of the depressed infants. The findings suggest that general anaesthesia, rather than asphyxia or aortocaval compression, is responsible for most of the depressed infants born by elective Caesarean section. This may involve over 20% of babies delivered in this manner, so greater use of epidural block for elective Caesarean section is recommended. Further investigations are required to improve results with general anaesthesia.     

BLOOD LOSS DURING CAESAREAN SECTION UNDER GENERAL ANAESTHESIA

Blood loss during Caesarean section has been measured in 121patients using a haemoglobin dilution method. The results havebeen analysed in an attempt to determine the importance on bloodloss of age, parity, previous Caesarean section, placental site,size of baby, length of operation, and surgical experience.The only statistically significant factors increasing bloodloss were (a) multipara undergoing their first Caesarean section(particularly emergency section) and (b) a low anterior placenta.Heavy blood loss, especially in patients with a low haemoglobin,was associated with an increased incidence of postoperativepyrexia.     

Circulatory collapse following epidural bolus for Caesarean section a profound vasovagal reaction? A case report

IntroductionReduced blood pressure is commonly seen associated to spinal anaesthesia for Caesarean section and efforts to reduce its occurrence and its magnitude is common practice. Cardiovascular collapse requiring cardio-pulmonary resuscitation after putting the spinal/epidural block for Caesarean section is however a rare but most dramatic event.Presentation of caseWe describe a case with sudden short loss of circulation, circulatory collapse, short after start of emergency Caesarean section in top up epidural anaesthesia (3 + 12 ml ropivaciane 7.5 mg/ml), requiring CPR. The neonate was delivered during CPR with Apgar 1, 10, 10 at 1, 5 and 10 min. Circulation was restored following 60–90 s of CPR and administration of 0.5 mg adrenaline. No cardioversion was administered sinus rhythm was regained spontaneously. The mother and child had a further uncomplicated course. No signs of cardiac damage/anomaly, emboli, septicaemia, pereclampisa or local anaesthetic toxicity was found. The patient had prior to the decision about Caesarean section had fever and was subsequently relatively dehydrated.DiscussionThe patient had a fast return of sinus rhythm following birth of the child, without cardioversion. None of common causes for cardiac arrest was found and the patient an uncomplicated post Caesarean section course. The combination of epidural induced sympathetic block and reduced preload possibly triggered a Bezold-Jarisch reflex with a profound vasovagal reaction.ConcluiosnA structured plan for the handling of cardiovascular crisis must be available wherever Caesarean section are performed. Adequate volume loading, left tilt and vigilant control of circulation following regional block performance is of outmost importance.     

Detecting awareness during general anaesthetic Caesarean section An evaluation of two methods

Seventy-four patients received general anaesthesia for Caesarean section. Seven percent of the elective group and 28% of the emergency patients reported dreaming or recall of voices during the procedure (p less than 0.05) at postoperative interview. One patient from each group reported feeling pain or suffocation. All patients were monitored for awareness using the isolated forearm technique and lower oesophageal contractility. Provoked lower oesophageal contractility was the most effective of the different indices. A value greater than 35 mmHg on at least one occasion had a false negative rate of 33%, a false positive rate of 28% and a predictive value of 25%. A value greater than 13 mmHg picked up all patients who dreamed, with a false positive rate of 68%. Both of the 'aware' patients had provoked lower oesophageal contractility response of greater than 70 mmHg, an attribute shared by only 8% of the rest. The isolated forearm was particularly ineffective.     

Epidural ropivacaine 7.5 mg/ml for elective Caesarean section: A double-blind comparison of efficacy and tolerability with bupivacaine 5 mg/ml

BACKGROUND: Ropivacaine is a new local anaesthetic drug known to be less cardiotoxic than bupivacaine. The aims of this comparative study with bupivacaine were to evaluate efficacy, safety and tolerability for the mother and the neonate when using ropivacaine 7.5 mg/ml for epidural anaesthesia for elective Caesarean section. METHODS: In a double-blind, multicentre trial the patients were randomised to receive 20 ml of either ropivacaine 7.5 mg/ml or bupivacaine 5 mg/ml. The quality of the peroperative analgesia and abdominal muscle relaxation as well as tolerability and safety in both the mother and the neonate were evaluated. RESULTS: A total of 122 patients were evaluated for efficacy and tolerability. There were no significant differences in the onset time and the extent of the sensory spread or motor block. The peroperative quality of anaesthesia and muscle relaxation was similar in both groups. No significant side effects were observed, except for a more profound drop in systolic blood pressure in the ropivacaine group. The anaesthetics were well tolerated by the neonate in both groups, evaluated by Apgar and NACS scores. CONCLUSION: Ropivacaine 7.5 mg/ml administered epidurally resulted in equally effective anaesthesia for Caesarean section as bupivacaine 5 mg/ml. Because of the lower cardiotoxicity of ropivacaine, the new amide has a potential in replacing bupivacaine when used epidurally for Caesarean section.     

Post-caesarean section analgesia: a comparison of epidural butorphanol and morphine

Epidural butorphanol 1, 2 and 4 mg were compared with morphine, 5 mg, for postoperative analgesia in 92 consenting, healthy, term parturients who had undergone Caesarean section under epidural lidocaine anaesthesia in a randomized double-blind study. Postoperative pain was assessed using a visual analogue scale and recorded with heart rate, blood pressure and respiratory rate. The demographic characteristics, and the incidences of primary and repeat Caesarean sections, were not different among the four treatment groups. At 15, 30, 45 and 60 min after treatment the median pain scores following butorphanol were similar and lower than those following morphine (P less than 0.05). Calculated median percentage pain relief values for butorphanol were higher than morphine at each of these times (P less than 0.05). At 90 min and 2 hr the pain scores and pain relief values were similar. Beyond 45 min the number of patients requesting supplemental medication and dropping out of the study increased progressively in both the butorphanol and morphine treated patients. The attrition profiles for butorphanol were different from morphine (P less than 0.01). The median time in the study was greater than 24 hr for morphine, and 3, 2.5 and 4 hr for butorphanol, 1, 2 or 4 mg, respectively. No patient developed a clinically important change in heart rate or blood pressure, and none experienced a decrease in respiratory rate below 12 breaths.min-1. One of 69 patients (1.4 per cent) who received butorphanol developed pruritus compared with ten (43 per cent) of 23 patients who received morphine. The global assessments of the adequacy of analgesia were indistinguishable between morphine and butorphanol. Epidural butorphanol provides safe, effective postoperative analgesia, has a prompt onset, and a limited duration.     

Intrathecal diamorphine for analgesia after Caesarean sectionA dose finding study and assessment of side-effects

Eighty women undergoing elective Caesarean section under spinal anaesthesia using hyperbaric bupivacaine 0.5% were randomly allocated to receive, in addition, intrathecal diamorphine 0.125, 0.25 or 0.375 mg or saline. Postoperative morphine requirements, measured using a patient-controlled analgesia system, were reduced in a dose-dependent manner by diamorphine. Pain scores were significantly lower at 2 and 6 h following the two larger doses of diamorphine. Less supplemental analgesia was required intra-operatively if intrathecal diamorphine had been given. The incidences of vomiting and pruritus were also dose-related. No respiratory rates of less than 14 breath.min⁻¹ were recorded and the incidence of oxygen saturation readings less than 95% and 90% did not differ between groups. There were no adverse neonatal effects. Intrathecal diamorphine in the present study was found to be safe in doses of up to 0.375 mg following Caesarean section. However, minor side-effects were frequently observed.     

Intrathecal morphine for Caesarean section: an assessment of pain relief, satisfaction and side-effects

In a prospective, randomised, double-blind study of 60 patients who had an elective Caesarean section under spinal anaesthesia we compared 0.1 mg intrathecal morphine with intrathecal saline placebo. All patients received morphine intravenously by patient-controlled analgesia after the operation. Pain, satisfaction and side-effects were assessed at 4 and 24 h after the operation. Pain measured by a 100-mm visual analogue scale was less in the intrathecal morphine group at both times (p <0.05) and morphine consumption was lower (p <0.01). At 4 h the intrathecal morphine group had more pruritus (p <0.001) but there was no difference in satisfaction. At 24 h there was no significant difference in side-effects, but overall satisfaction measured by visual analogue scale was better in the intrathecal morphine group (p <0.01). Intrathecal morphine improves pain relief and patient satisfaction after Caesarean section.     

EFFECT OF POSTURE DURING THE INDUCTION OF SUBARACHNOID ANALGESIA FOR CAESAREAN SECTION: Right v. Left Lateral

Thirty-five women scheduled for elective Caesarean section wererandomly assigned to have subarachnoid analgesia induced ineither the right or left lateral position. They were then turnedsupine with a wedge under the right hip. No patient in the right-sidedgroup required further analgesia. Five patients in the left-sidedgroup required postural manipulation to encourage the spreadof analgesia and two required supplementary analgesia (P <0.01).     

Comparison of pentastarch and Hartmann's solution for volume preloading in spinal anaesthesia for elective caesarean section

We studied 160 patients undergoing elective Caesarean section under spinal anaesthesia who received a preloading volume of 15 ml kg-1 of 10% pentastarch in 0.9% saline, or Hartmann's solution, in a prospective, randomized, double-blind study. We compared the incidence of spinal-induced hypotension in each group. Hypotension was defined as a decrease in systolic arterial pressure to less than 70% of baseline values or < or = 90 mm Hg, whichever was the greater. The groups were comparable in physical characteristics and there was no serious morbidity. Fetal outcome was similar in both groups. Significantly more patients in the Hartmann's group (n = 38, 47.5%) developed hypotension than in the pentastarch group (n = 10, 12.5%) (P < 0.0001). Linear regression analysis showed that the only significant variable was type of fluid used. Blood glucose concentrations were not related to the presence of hypotension. We conclude that starches may be suitable for preloading in Caesarean section under spinal anaesthesia and provide an alternative to the aggressive use of vasoconstrictors.      

The use of remifentanil in general anaesthesia for Caesarean section in a patient with mitral valve disease

We report the use of remifentanil as part of a general anaesthetic technique for a patient with mixed mitral valve disease, asthma and pre-eclampsia presenting for an emergency Caesarean section. The use of remifentanil was associated with stable haemodynamic variables during general anaesthesia. No clinically significant respiratory depression was noted in the neonate.