Neurologic And Adaptive Capacity Scores Research Articles

A randomized study of the effects of perioperative i.v. lidocaine on hemodynamic and hormonal responses for cesarean section

Intravenous infusion of lidocaine attenuates the stress response to surgery. We aimed to evaluate the effects of perioperative lidocaine on the hemodynamic and hormonal responses for cesarean delivery. After the gaining of ethical approval, 90 patients scheduled for elective cesarean delivery were randomly allocated to receive either lidocaine 1.5 mg x kg(-1) i.v. bolus 30 min before induction, followed by an infusion of 1.5 mg x kg(-1) x h(-1) until 1 h after surgery (n = 45), or saline placebo (n = 45). Anesthesia was maintained with 50% nitrous oxide in oxygen with 0.7% isoflurane. Hemodynamic variables, plasma cortisol, maternal and neonatal lidocaine concentrations, Apgar scores at 1 and 5 min, neonatal acid-base status, and the neurologic and adaptive capacity score (NACS) were recorded. After induction, patients receiving lidocaine had a smaller increase in heart rate and mean arterial blood pressure (P < 0.02) and lower plasma cortisol concentrations (31.1 +/- 9.91 vs 45.6 +/- 8.43 microg x dL(-1); P < 0.001). There were no differences between the two groups in Apgar scores, NACS, or neonatal acid-base status. After delivery, maternal and umbilical venous concentrations and umbilical vein-to-maternal vein ratios of lidocaine were 2.05 +/- 0.42 microg x mL(-) and 1.06 +/- 0.31 microg x mL(-1), and 0.52 +/- 0.07, respectively. Perioperative lidocaine is safe and effective in attenuating the maternal stress response to surgery for cesarean delivery.

Transfer of Tramadol and its Metabolite into Breastmilk

Purpose of the study: To investigate the transfer of rac-tramadol and its rac-O-desmethyl metabolite into transitional milk, to estimate the absolute and relative infant doses via milk, and to assess unwanted effects in the breastfed infant. Methods: Tramadol HCl (100 mg six hourly) was administered to 75 breastfeeding mothers for postoperative analgesia on days 2–4 after caesarian section. Three samples of transitional milk and one of plasma were collected over 6–14 h following the 4th dose. Tramadol and O-desmethyltramadol were measured by high performance liquid chromatography. Milk/plasma ratio (M/P) was calculated, and absolute infant dose and relative infant dose were calculated by standard methods. The behavioral characteristics of the exposed breastfed infants and a matched control group of infants not exposed to tramadol were also studied. Results: Mean (95% CI) M/P was 2.2 (2.0–2.4) for tramadol and 2.8 (2.5–3.1) for O-desmethyltramadol. Average concentrations in milk across a 6 h dose interval at steady-state were 748 (681–815) mcg l−1 for tramadol and 203 (188–217) mcg l−1for O-desmethyltramadol. Estimated absolute and relative infant doses were 112 (102–122) mcg kg−1 day−1 and 30 (28–32) mcg kg−1 day−1, and 2.24 (2.04–2.44)% and 0.64 (0.59–0.69)% for tramadol and O-desmethyltramadol respectively. The exposed infants and control breastfed infants had similar characteristics, including Apgar scores at birth and Neurologic and Adaptive Capacity Scores (NACS) on days 3–4 after birth. Conclusions: The absolute infant doses for tramadol and its active metabolite combined were around 14% of the child therapeutic dose for tramadol. The combined relative infant dose of 2.88% of the weight-adjusted maternal dose was also low. The similarity of NACS in exposed infants and controls suggests that there were no clinically significant effects on infant well-being. We conclude that short-term maternal use of tramadol during establishment of lactation is safe for the breastfed infant.

Influence of Volume Preloading on Uteroplacental and Fetal Circulation during Spinal Anaesthesia for Caesarean Section in Uncomplicated Singleton Pregnancies

Objective: Effects of volume preloading during spinal anaesthesia for elective caesarean section on maternal blood pressure, feto-maternal circulation and fetal outcome. Patients and Methods: In a pilot study a randomised trial was performed in 22 healthy women with uncomplicated, singleton pregnancies at 36–40 weeks of gestation undergoing elective caesarean section under spinal anaesthesia. In the low volume group (group A) patients received 150 ml of crystalloid solution for preloading, in the high volume group (group B) they were given 15 ml/kg of crystalloid solution for preloading before the initiation of spinal anaesthesia. Maternal blood pressure was monitored intermittently. Hypotension was defined as a decrease in systolic pressure to less than 80% of the baseline value. The Doppler flow evaluation consisted of measurements from the uterine artery at the placental site, fetal umbilical artery and fetal middle cerebral artery. Pulsatility indices were derived before and after fluid preloading, and when spinal anaesthesia was established. The neonatal outcome was assessed by Apgar scores, arterial acid base status and neurologic and adaptive capacity scores (NACS). Results: The incidence of maternal hypotension in both groups was 45.5% (n = 10); 3 cases occurred in group A compared to 7 cases in group B (n.s.). There was no evidence that the high dose volume is useful in preventing maternal hypotension. The pulsatility indices of uterine arteries, umbilical arteries and middle cerebral arteries were not altered. Statistical analysis showed no changes in neonatal outcome concerning umbilical arterial pH, Apgar score and NACS (n.s.) between groups A and B. Conclusions: Our preliminary results suggest that high dose crystalloid volume preloading has no preventive function in the avoidance of maternal hypotension in healthy parturients undergoing elective caesarean section under spinal anaesthesia, and shows no harmful effects on neonatal outcome as long as maternal hypotension is corrected immediately. However, the statistical significance may reflect the small sample size, and larger series are needed before changing the current management.

The Neurologic and Adaptive Capacity Score: a systematic review of its use in obstetric anesthesia research.

The Neurologic and Adaptive Capacity Score: a systematic review of its use in obstetric anesthesia research.

The Neurologic and Adaptive Capacity Score (NACS)

The Neurologic and Adaptive Capacity Score (NACS)

ROPIVACAINE 7.5 MG/ML FOR EPIDURAL ANESTHESIA IN ELECTIVE CESAREAN SECTION

S361 INTRODUCTION: Ropivacaine is a new local anesthetic agent belonging to the same homologue series of compounds as bupivacaine. Because of cardiotoxicity bupivacaine 7.5 mg/ml has been unavailable to obstetric anesthesiologists for more than a decade [1]. The new agent ropivacaine has been shown to have a lower cardiovascular and cerebral toxicity than bupivacaine [2,3] thus allowing the clinical use of higher concentrations in obstetric anaesthesia [4]. METHOD: With Institutional Ethics Committee approval and informed written consent. 120 patients for elective Cesarean section were enrolled in a prospective, single-center, randomized, double-blind study. Patients were randomized to receive either ropivacaine 7.5 mg/ml or bupivacaine 5 mg/ml epidurally. After receiving a main dose of 20 ml over 5 minutes the patients could, if required for adequate anesthesia, receive a blinded administration of two 5 ml top-up doses. The first top-up dose in the ropivacaine group was active drug, while the second dose was normal saline. In the bupivacaine group both top-up doses were active drug. STATISTICAL METHODS: The treatment groups were compared using Wilcoxon (mid) rank tests. A p-value <0.05 was considered statistically significant. Where there are missing data the actual number of patients is shown (/n). RESULTS: 60 patients were randomized to receive ropivacaine (Group R) and 60 patients bupivacaine (Group B), and all were valid for safety analysis. Three patients in Group R and 1 in Group B were judged to have been technical failures and were removed from the efficacy analysis. The remaining 57 Group R patients and 59 Group B were valid for safety and efficacy analysis. However 5 patients in group R and 7 patients in group B are not included in the analysis of motor block since they received additional analgesia before the assessments. Both treatment groups were similar with regard to concomitant diseases and demographic variables, except for weight, where the ropivacaine group had a mean weight of 5.3 kg greater than the bupivacaine group. In Group R, 7 patients received 187.5 mg of study drug and the remaining 53 received 150 mg. In Group B, 5 patients received 150 mg, 5 patients 125 mg and 50 patients received 100 mg. The median time to T6 block was 4 and 5 minutes after the end of the main dose in Groups R and B respectively. The maximum upper spread of sensory block varied between T6 and C3 in Group R and between T10 and C3 in Group B. 26/52 Group R patients (50%) and 15/52 Group B patients (29%) had grade 3 motor block at the assessments after surgery, according to the modified Bromage scale (no statistical difference). Pain at delivery was experienced by 15/57 (26%) Group R patients compared to 17/59 (29%) Group B patients. Quality of analgesia was excellent in 43/57 (75%) Group R patients compared to 38/59 (64%) Group B patients (nsd). The median value of the maximum drop in maternal systolic blood pressure as a percentage of baseline was -40% in Group R compared to -38% in Group B (nsd). The Apgar score obtained in neonates 5 minutes after delivery was 10 in all Group R patients and either 9 or 10 in Group B. The median Neurologic and Adaptive Capacity Score (NACS) 2 hours after delivery were 37 in both groups, and 24 hours after delivery, 39 in both groups. CONCLUSIONS: The present study shows that ropivacaine 7.5 mg/ml can be safely administered epidurally in doses up to 150 - 187 5 mg and provides excellent anesthesia for elective Cesarean section.

Comparison of 0.25% ropivacaine and bupivacaine for epidural analgesia for labor and vaginal delivery

Study Objective: Part 1: To measure ropivacaine levels in the mother and infant at delivery after continuous lumbar epidural infusion. Part 2: To compare epidural ropivacaine to epidural bupivacaine for labor analgesia in regard to effectiveness, motor blockade, and maternal and neonatal effects. Design: Part 1: Open-labelled, non-blind study. Part 2: Randomized, double-blind study. Setting: Labor and delivery units of two academic hospitals. Patients: Part 1: 20 ASA physical status I and II parturients in active labor. Part 2: 81 ASA physical status I and II parturients in active labor. Interventions: For Part 1, 8 to 12 ml of 0.25% ropivacaine was administered through a lumbar epidural catheter to achieve a T 10 dermatomal sensory level. An infusion of 0.25% ropivacaine, 8 to 10 ml/hr, maintained this sensory level. Maternal and umbilical cord blood samples obtained at delivery were analyzed for ropivacaine concentration. For Part 2, anesthetic management was similar to that previously described except patients were randomized to receive either 0.25% ropivacaine or 0.25% bupivacaine. Onset, regression, maximal spread of sensory block, and onset and degree of motor blockade were measured. Contraction pain as assessed using a visual analog scale (VAS), maternal blood pressure, and heart rate were determined every 5 minutes until a stable VAS-contraction score was achieved, and every 30 minutes thereafter. Neonatal assessment included Apgar scores and neurologic and adaptive capacity scores (NACS) at 15 minutes, 2 hours, and 24 hours. Measurements and Main Results: For Part 1, the total and free maternal arterial concentrations of ropivacaine at delivery were 0.64 ± 0.14 μg/ml and 0.10 ± .02 μg/ml, respectively; the umbilical venous total and free concentrations were 0.19 ± 0.03 μg/ml and 0.12 ± 0.07 μg/ml, respectively (n = 12). The umbilical arterial and venous concentrations did not differ for both the free and total concentrations. For Part 2, there was no difference between ropivacaine and bupivacaine in the variables measured. Umbilical cord gases and Apgar scores were not different between the two groups; NACS were higher at 15 minutes and 2 hours in the ropivacaine group ( p < 0.05) than the bupivacaine group. Conclusion: Both ropivacaine and bupivacaine produced excellent analgesia for labor with no major adverse effect on the mother or neonate.

Desflurane analgesia for vaginal delivery

The use of subanaesthetic concentration of inhalational anaesthetic for vaginal delivery offers many advantages to the mother and newborn. Desflurane, with the characteristics of rapid onset and minimal metabolism, may provide better analgesia and safety for labour pain control. Eighty healthy parturients were randomly assigned to receive either desflurane 1.0-4.5% and oxygen (n = 40) or nitrous oxide 30-60% in oxygen (n = 40). Analgesia was assessed using a score from 0 (no relief) to 4+ (excellent analgesia), amnesia for the delivery, blood loss were recorded. Neonates were evaluated by Apgar scores and neurologic and adaptive capacity scores (NACS). Data were analyzed for statistical significance using Student's t-test or Chi-square when appropriate. Analgesia scores were similar for both groups with more amnesia in desflurane group (23% vs 0% P < 0.05). Blood loss did not differ significantly, 364 ml for the desflurane group and 335 ml for the nitrous oxide group. There were no significant differences for neonatal Apgar score at 1 min or at 5 min or the NACS at 2 hr or 24 hr between the two groups. We conclude that desflurane in subanaesthetic doses is safe and effective inhalation agent for normal delivery but might be associated with amnesia.

Vecuronium for Rapid-Sequence Intubation for Cesarean Section

Because succinylcholine may occasionally be contraindicated for rapid-sequence induction in parturients, we studied the use of vecuronium in 21 patients having elective cesarean sections. Eleven patients (group 1) received 10 micrograms/kg vecuronium as a priming dose, followed 4-6 min later by 100 micrograms/kg. Ten patients (group 2) received 200 micrograms/kg vecuronium as a bolus. Onset, the time from the injection of vecuronium to maximal twitch suppression, and clinical duration, the time between vecuronium administration and return to 25% of the control twitch height, were recorded. Umbilical and maternal venous blood samples at delivery were analyzed for vecuronium concentrations. One-minute and 5-min Apgar scores and 1- and 24-h Neurologic and Adaptive Capacity Scores (NACS) were recorded. Individual tests of passive and active tone within the overall NACS profile were compared to evaluate further any residual vecuronium effects in the infants. Onset of neuromuscular blockade was 177 s in group 1 and 175 s in group 2. The corresponding clinical durations were 73 and 115 min. Maternal and umbilical venous vecuronium concentrations were 515 and 73 ng/mL in group 1 and 838 and 107 ng/mL in group 2. Seventy percent of neonates in group 1 had Apgar scores greater than 7 at 1 min, with 100% greater than 7 at 5 min. Corresponding values in group 2 infants were 50% and 80%. Fifty percent of group 1 infants had NACS of 35-40 at 1 h, and 70% at 24 h.(ABSTRACT TRUNCATED AT 250 WORDS)

Propofol infusion anaesthesia for Caesarean section

Two propofol infusion regimens and a standard general anaesthetic were compared in thirty Chinese women undergoing elective Caesarean section. After induction of anaesthesia with propofol 2 mg.kg-1, ten patients received propofol 6 mg.kg-1.hr-1 and nitrous oxide 50 per cent in oxygen while ten were given propofol 9 mg.kg-1.hr-1 with 100 per cent oxygen. The other ten patients received thiopentone 4 mg.kg-1 and nitrous oxide 50 per cent in oxygen with enflurane one per cent. Maternal recovery times and psychomotor performance were recorded. Neonates were assessed by Apgar scores, neurologic and adapative capacity scores (NACS) and umbilical cord blood gas analysis. Haemodynamic changes were similar immediately following induction but the low propofol infusion group had the best haemodynamic stability subsequently. Recovery times were fastest in the low-infusion group but there were no differences in later postbox testing. Neonatal Apgar scores and umbilical blood gas analysis were similar but NACS at two hours were poorer in the high infusion group. A propofol infusion coupled with nitrous oxide appears to be a satisfactory technique for Caesarean section.