The influence of epidural pethidine on shivering during lower segment caesarean section under epidural anaesthesia

A prospective study of 94 patients undergoing elective lower segment caesarean section under epidural anaesthesia was performed in order to determine the incidence of shivering and the influence of epidural pethidine. Epidural anaesthesia was established with bupivacaine 0.5% with adrenaline, with or without additional lignocaine 2% with adrenaline, to total 20-25 ml. With the injection of epidural local anaesthesia an extra 5 ml of solution was administered into the epidural space--pethidine 25 mg preservative-free, in normal saline, or normal saline alone. Patient, administering anaesthetist and observer were blinded to the nature of the test substance. Shivering was assessed by an independent observer and subsequently rated by the patient. Other side-effects also recorded were nausea, vomiting, pruritis and drowsiness. The incidence of shivering was 36% in the control (saline) group and 11% in the pethidine group. The difference was highly significant (P less than 0.01). There was no significant difference in the incidence of maternal nausea, vomiting, drowsiness or pruritis, or neonatal Apgar scores. Cord blood samples were assayed for pethidine, revealing low or absent pethidine concentrations.     

Epidural analgesia in labour using intermittent doses determined by midwives

Since 1985 midwives have been responsible for choice of drug and timing of epidural top-up doses for women in labour at Flinders Medical Centre. The midwife may choose from one of three different prescribed preparations, namely: bupivacaine 12.5 mg plus pethidine 25 mg, bupivacaine 25 mg, and bupivacaine 50 mg - each made up in a volume of 10 ml. This prospective study examined the incidence of adverse effects and level of patient satisfaction with midwife-managed epidural analgesia. Between 1987 and 1992, 6935 women received midwife-managed epidural analgesia. The pethidine/bupivacaine mixture was generally used for the first dose (75% of women) with a shift towards bupivacaine 25 mg or 50 mg for subsequent top-ups. Sixty-one per cent of women had normal vaginal deliveries, 25% instrumental and 14% caesarean deliveries. The most common side-effects were shivering, hypotension and itch. Shivering occurred following 11% of bupivacaine, and 2% of bupivacaine/pethidine top-ups. Itching was more common after bupivacaine/pethidine (3%) than after bupivacaine (1%). Women reported a high level of satisfaction with the overall experience of childbirth, though this was lower for instrumental and caesarean deliveries than for vaginal deliveries. On the other hand, satisfaction with pain relief provided by the epidural was greater in women who had caesarean or instrumental deliveries. The most commonly cited benefits of epidurals were good pain relief (83%), ability to cope (74%), feeling relaxed (67%), and being aware (60%), while feeling numb (23%) and experiencing severe pain at delivery (17%) were the most common causes of dissatisfaction.     

Comparison between alfentanil, pethidine and placebo in the treatment of post-anaesthetic shivering

We have compared the effects of pethidine, alfentanil and placebo in the treatment of post-anaesthetic shivering. Ninety patients who shivered after routine surgery were allocated randomly to receive normal saline (n = 30), alfentanil 250 micrograms (n = 30) or pethidine 25 mg (n = 30). After 10 min, 26 patients had stopped shivering in the pethidine group which was significantly more than the incidence in the two other groups (placebo = 7; alfentanil = 12) (P < 0.0002). Alfentanil was not significantly different from normal saline in affecting shivering. We conclude that alfentanil 250 micrograms was not effective in the treatment of post-anaesthetic shivering.      

Comparison between pentazocine, pethidine and placebo in the treatment of post-anesthetic shivering

BACKGROUND: We have compared the effects of pethidine, pentazocine and placebo in the treatment of post-anesthetic shivering. METHODS: Forty-five patients who shivered after routine surgery were allocated randomly to receive normal saline (n=15), pentazocine 7.5 mg (n=15) or pethidine 17.5 mg (n=15). RESULTS: After 10 min, 13 patients had stopped shivering in the pethidine group, which was significantly more than the incidence in the two other groups (placebo=2; pentazocine=4) (P<0.01). Pentazocine was not significantly different from normal saline in affecting shivering. CONCLUSION: We conclude that pentazocine 7.5 mg was not effective in the treatment of post-anesthetic shivering.     

A comparison of epidural infusions in the combined spinal/epidural technique for labor analgesia

We compared the clinical effects of three epidural infusions initiated after subarachnoid medication was administered as part of the combined spinal/epidural technique for labor analgesia. Fifteen minutes after administering subarachnoid fentanyl 25 microg and 1 mL of bupivacaine 0.25%, and 5 min after an epidural test dose of 3 mL of bupivacaine 0.25%, women were randomized to receive an epidural infusion of saline, bupivacaine 0.125%, bupivacaine 0.0625%, or bupivacaine 0.04% with epinephrine 1:600,000. All epidural infusions were started at 10 mL/h, and all except the Saline Group also received fentanyl 2 microg/mL. The end point of the study was delivery or request for additional medication for analgesia. We found that time until request for additional analgesia was longest in women who received bupivacaine 0.125% (median duration, 300 min) versus saline (median duration, 118 min) (P = 0.0001) and was intermediate for bupivacaine 0.0625% and bupivacaine 0.04% (median duration, 162 and 180 min, respectively) (P = 0.0001 versus saline). Women who received bupivacaine 0.125% had the most motor block. We conclude that all the bupivacaine-based infusions we tested maintained the analgesia from subarachnoid medication longer than saline, with the longest duration, but the most motor block, from bupivacaine 0.125%. IMPLICATIONS: In this prospective, randomized, and double-blinded study we found that initiating an epidural infusion of bupivacaine 0.125% with fentanyl 2 microg/mL at 10 mL/h 15 min after subarachnoid fentanyl 25 microg with 1 mL of bupivacaine 0.25%, followed by an epidural test dose of 3 mL of bupivacaine 0.25%, maintained the analgesia for longer but with more motor block than with either bupivacaine 0.04% or bupivacaine 0.0625%.     

Anaesthetic temperature and shivering in epidural anaesthesia

The mechanism of shivering during epidural analgesia remains unclear. This study investigates the role of the temperature of the local anaesthetic injected extradurally. Forty patients admitted for elective caesarean section under epidural anaesthesia were studied; 20 were given bupivacaine warmed to 37°C: (warm group) and 20 were given hupivacaine stored at 4°C (cold group); the occurrence of shivering in both groups was recorded. The overall incidence of shivering was 27.5%; two patients of the warm group and nine patierits of the cold group shivered. This difference was statistically significant ( P <0.03). The results suggest that there are thermosensory mechanisms in the human spinal canal. In our view, epidural anaesthetic solutions should be warmed to body temperature prior to injection to reduce the incidence of shivering.     

帕瑞昔布钠预防硬膜外麻醉后寒战的临床观察

目的探讨预先静注帕瑞昔布钠对硬膜外麻醉后寒战的预防效果。方法选择硬膜外麻醉下行择期经尿道前列腺切除手术患者120例,随机均分为两组。硬膜外麻醉前30 min分别静注帕瑞昔布钠40 mg(P组)或等容量生理盐水(C组)。观察麻醉及手术过程中寒战的发生率、寒战的严重程度及寒战发生前后体温变化。结果 P组患者寒战发生率为5%,而C组为25%,P组明显低于C组(P<0.05)。结论预先静注帕瑞昔布钠40 mg可有效预防硬膜外麻醉后寒战的发生。     

Effect of Pethidine, Fentanyl and Morphine on Post-Operative Shivering in Man

One hundred consecutive patients who shivered following general or regional anesthesia and a surgical procedure were randomly treated with 25 mg pethidine, 2.5 mg morphine, 25 micrograms fentanyl or sodium chloride 0.9%, given in equal intravenous volumes over a 15-min period. The effects were evaluated every 5 min after the first injection. There was a spontaneous, time-related disappearance of shivering in the sodium chloride-treated patients. In the pethidine-treated group, shivering disappeared more than twice as fast as in the control group. The difference was highly significant at 15 and 20 min (P less than 0.001) and was unrelated to weight, body temperature or duration of anesthesia. Women responded sooner than men, reaching significance at 10 min (P less than 0.05), while men did so only at 20 min. Morphine or fentanyl had no effect. Nausea and vomiting were minimal and of equal incidence in narcotic- and placebo-treated patients.     

Intravenous meperidine for control of shivering during Caesarean section under epidural anaesthesia

To determine the efficacy of meperidine in controlling shivering during epidural anaesthesia for Caesarean section, forty-six parturients were studied. After delivery of the infant, shivering patients received either a single dose of intravenous meperidine 50 mg, or saline in a randomized double-blind fashion. Shivering was classified on a scale of 0 to 3 (grade 0 = none, grade 3 = severe shivering that was distressing to the patient and interfered with monitoring). Shivering and other variables were recorded at epidural placement, skin incision, delivery, and 2,5,15,30 and 60 minutes following injection. Administration of meperidine resulted in a significant decrease in both the overall incidence of shivering (87 to 35 per cent, p < 0.0 J) and severity of shivering (grade 3: 57 to 0 per cent, p < 0.01), compared with saline (incidence: 87 to 83 per cent, grade 3:57 per cent, no change). This effect was apparent within two minutes of drug injection and persisted throughout the study period. There were no differences in vital signs, oxygen saturation or temperature between groups. The incidence of nausea was similar, although patients receiving meperidine were more drowsy at two and five minutes following injection (p < 0.01) compared with patients in the saline group. There were no differences in level of consciousness at the later intervals. The mechanism of action of meperidine on shivering remains to be elucidated.     

DOUBLE-BLIND COMPARISON BETWEEN DOXAPRAM AND PETHIDINE IN THE TREATMENT OF POSTANAESTHETIC SHIVERING

Sixty patients who shivered after routine surgery under generalanaesthesia were allocated randomly to receive normal saline(n = 20), doxapram 1.5mg kg^–1 (n = 20) or pethidine 0.33mgkg^–1 (n = 20). Both doxapram and pethidine were effectivein treating postoperative shivering 2–3 mm after i.v.administration. In the group who received normal saline, 15patients were still shivering 10 min after treatment, whilstin the doxapram group only three patients were shivering atthat time. In the pethidine group, all patients had stoppedshivering by 7 min after treatment. We conclude that both doxapramand pethidine were effective in the treatment of postoperativeshivering. (Br. J. Anaesth. 1993; 71: 685–688)     

Comparison of the effects of intrathecal morphine and pethidine on shivering after Caesarean delivery under combined-spinal epidural anaesthesia

We performed a prospective, randomised, double blind study to compare the antishivering effect of morphine and pethidine when added to intrathecal hyperbaric bupivacaine during elective Caesarean delivery under combined-spinal epidural anaesthesia. Spinal anaesthesia consisted of either 8-10 mg of 0.5% bupivacaine alone (group B; n = 30) with 0.1 mg morphine (group BM0.1; n = 29), with 0.2 mg morphine (group BM0.2; n = 30), or with 10 mg pethidine (group BPeth10; n = 30). The incidences of shivering were 23.3% (7/30) in group B, 17% (5/29) in group BM0.1, 13.3% (4/30) in group BM0.2 and 3.3% (1/30) in group BPeth10 (p < 0.05). The shivering intensity for each patient was significantly higher in group B than the other groups. In conclusion, intrathecal pethidine added to hyperbaric bupivacaine reduces the incidence and intensity of shivering more than does morphine (0.1 or 0.2 mg).     

The clinical effectiveness of epidural bupivacaine, bupivacaine with lidocaine, and bupivacaine with fentanyl for labor analgesia

STUDY OBJECTIVE: To examine the efficacy of bupivacaine alone and in combination with lidocaine or fentanyl for epidural analgesia during labor. DESIGN: Randomized, single-blind study. SETTING: Labor and delivery unit at a university medical center. PATIENTS: Forty-five primiparas requesting epidural analgesia. INTERVENTIONS: Following epidural placement at L3-4 interspace, patients received either bupivacaine 0.5% (Group 1, n = 15), bupivacaine 0.25% with lidocaine 1% (Group 2, n = 15), or bupivacaine 0.5% with fentanyl 50 micrograms in 10 ml of saline (Group 3, n = 15). Patients in Groups 1 and 2 received 6 to 10 ml of local anesthetic depending on patient height, while patients in Group 3 received 5 ml of local anesthetic plus 50 micrograms of fentanyl in 10 ml of saline. All solutions contained epinephrine 1:200,000. MEASUREMENTS AND MAIN RESULTS: Patients were assessed at regular intervals following administration of the epidural solution. Visual analog scale (VAS) scores were used to measure onset of analgesia, time to complete pain relief, duration of analgesia, and patient satisfaction with therapy. The frequency of shivering and pruritus and the extent of sensory/motor block also were evaluated. There were no intragroup differences in time to complete pain relief or patient satisfaction. However, patients in Group 3 noted the most rapid onset and longest duration of pain relief. Patients in Group 3 also experienced significantly less shivering and had the lowest degree of motor block. Two patients in Group 3 experienced mild pruritus. CONCLUSIONS: Epidurally administered fentanyl safely extended the duration of labor analgesia while reducing bupivacaine dose requirements and magnitude of motor block. In this setting, the combination of bupivacaine and lidocaine offered no clinical advantage over bupivacaine alone.     

Efficacy of three doses of ketamine with bupivacaine for caudal analgesia in pediatric inguinal herniotomy

BACKGROUND AND OBJECTIVES: Ketamine administered systemically is a potent analgesic at subanesthetic plasma concentrations. Addition of ketamine to bupivacaine for caudal epidural block significantly prolongs the duration of postoperative analgesia. The purpose of this prospective, randomized double-blind study is to identify the optimal dose of ketamine that produces the maximum duration of caudal analgesia with minimal adverse effects as an adjuvant to bupivacaine for caudal epidural block. METHODS: Sixty children, aged 6 months to 10 years, undergoing inguinal herniotomy were allocated randomly to receive 1 of 3 solutions for caudal epidural block. Group 1 received 0.75 mL/kg of bupivacaine 0.25% with preservative-free ketamine 0.25 mg/kg, group 2 received 0.75 mL/kg of bupivacaine 0.25% with ketamine 0.5 mg/kg, and group 3 received 0.75 mL/kg of bupivacaine 0.25% with ketamine 1 mg/kg. Postoperative pain was assessed using the All India Institute of Medical Sciences pain discomfort scale. Rescue analgesia in the form of pethidine 1 mg/kg intramuscularly was administered when this score exceeded 4. RESULTS: The mean duration of caudal analgesia was 8.8 hours in group 1 compared with 22.1 hours in group 2 (P <.001) and 25.2 hours in group 3 (P <.001). Supplemental analgesia requirements with pethidine were significantly less in group 2 (4 subjects) and group 3 (no subject) when compared with group 1 (18 subjects). There were no differences between the groups in the incidence of motor blockade, urinary retention, emesis, or sedation. Group 3 had a significantly higher incidence of behavioral side effects such as odd behavior, agitation, or restlessness than groups 1 and 2. CONCLUSIONS: The optimal dose of ketamine in our study was 0.5 mg/kg added to 0.75 mL/kg bupivacaine 0.25% for caudal epidural block without an increase in side effects.     

The space blanket and shivering during extradural analgesia in labour

The incidence of shivering in women during epidural analgesia in labour is up to 33%, and may be highly distressing. Its mechanism is unclear, but the most widely held theory is that it is thermogenic. Pharmacological suppression may adversely effect the foetus or induce maternal hypothermia, and although physical remedies such as direct heat application are effective, they are also expensive and cumbersome. We recently found that the space blanket, a simple aluminised metallic foil, used pre-emptively, reduces shivering after general anaesthesia. We investigated the effect of the space blanket on the incidence and intensity of shivering, axilliary skin temperature, and subjective perception of cold during epidural analgesia for labour in 50 women over a four-hour time frame. Patients were randomised into group 1, who were wrapped in a space blanket immediately after commencement of epidural analgesia with bupivacaine, and group 2 (matched controls). Shivering was defined as visible tremor of the head, neck, trunk or limbs as observed by the attending midwives. Twenty-nine percent of group 1 and 35% of group 2 shivered (not significant), but a reduction in shivering intensity was observed in group 1 ( P <0.05). There was no significant difference in skin temperatures in either group, and no significant temperature change within the groups. Both groups had similar thermal comfort scores throughout the study, which correlated poorly with the presence of shivering. We conclude that there is no benefit in application of the space blanket to reduce epidural-analgesia related shivering in labour, which may indicate a non-thermogenic mechanism for this phenomenon.     

Haemodynamic effects of intravenous bupivacaine during high thoracic epidural anaesthesia

Administration of small doses of bupivacaine epidurally at the upper thoracic level will partially block the cardiac sympathetic nerves but not the sympathetic outflow via the adrenals. Local anaesthetics have direct systemic effects on the myocardium and the systemic circulation. The present study aimed to examine the effect of high thoracic epidural anaesthesia (TEA) in elderly patients, and to examine the effect of raising plasma bupivacaine concentrations in these patients, who had earlier had the sympathetic innervation of the heart blocked by thoracic epidural anaesthesia. Fifteen elderly patients scheduled for thoracotomy took part in the study. All received high thoracic epidural anaesthesia including the upper five thoracic dermatomes. When epidural block was established, ten patients received bupivacaine 3 mg/min intravenously for 20 min, while five patients received a corresponding volume of normal saline solution. After TEA was established, heart rate, mean arterial blood pressure and cardiac output decreased. When bupivacaine was given to these patients intravenously during the block, mean arterial blood pressure increased, while cardiac output decreased still more. The mechanisms behind these effects seem to be a direct constriction of the systemic blood vessels and a depressive effect on the myocardium, which was blocked from the influence of the cardiac sympathetic nerves by the high thoracic epidural block.     

I.v. clonidine prevents post-extradural shivering

We have studied the efficacy of i.v. clonidine to prevent shivering in 100 healthy patients who received extradural block for knee arthroscopy. Patients were randomly allocated to two groups. Just before extradural anaesthesia (0 min = baseline), group I (n = 50) received i.v. clonidine 1 microgram kg-1, group II (n = 50) received a saline bolus. Systolic arterial pressure (SAP), heart rate (HR), oxygen saturation (SpO2), cutaneous temperature and level of sedation, were all recorded at baseline and after 10, 20, 30, 45, 60 min. Shivering was evaluated by a blinded investigator for a period of 90 min and was graded as moderate or severe. Three patients in group I shivered compared with 19 in group II (P < 0.001). Patients with severe shivering were seen only in group II. There were no significant differences between the groups during the study period in SAP, HR, SpO2, cutaneous temperature or level of sedation. We conclude that preventive use of i.v. clonidine 1 microgram kg-1 provides a significant reduction in the incidence of post-extradural shivering without clinically relevant adverse side effects.      

Premedication with granisetron reduces shivering during spinal anaesthesia in children

This study evaluates the effect of prophylactic granisetron on the incidence of postoperative shivering after spinal anaesthesia in children. Eighty children, American Society of Anesthesiologists physical status I to II and aged two to five years were scheduled for surgery of the lower limb under spinal anaesthesia. The children were randomised to receive 10 μg/kg granisetron diluted in 10 ml saline 0.9% intravenously (group 1, n=40) or placebo (10 ml 0.9% saline, group 2, n=40) to be given over five minutes just before spinal puncture. Shivering, core temperature and the levels of motor and sensory block were assessed. No patients shivered in group 1. However, six patients shivered in Group 2 (P=0.025). There were no significant differences in the other measured variables between the groups. Granisetron is an effective agent to prevent shivering after spinal anaesthesia in children from two to five years of age.     

Epidural pethidine and bupivacaine in labour

A double-blind randomised study was performed to assess the value of the addition of pethidine 50 mg to the initial dose of bupivacaine given for epidural analgesia in labour. Forty-nine patients received either 1 ml of saline (n = 24), or 50 mg of pethidine (n = 25), added to 9 ml of 0.25% bupivacaine as an initial injection for intrapartum epidural analgesia. There was a significant increase in the mean duration of analgesia in the pethidine group. However, pethidine did not increase the speed of onset of analgesia, or improve the quality of analgesia.     

Butorphanol for the relief of shivering associated with extradural anesthesia in parturients.

STUDY OBJECTIVE: To assess the efficacy of butorphanol for the relief of shivering following the epidural administration of 2% lidocaine. DESIGN: Randomized, double-blind study. SETTING: Labor and delivery department of a university-affiliated hospital inpatient facility. PATIENTS: Sixty-one healthy labor patients. INTERVENTIONS: Patients who had sustained shivering associated with lidocaine epidural anesthesia were given normal saline or butorphanol 1 mg. Patients were observed for 20 minutes following the administration of a study solution. MEASUREMENTS AND MAIN RESULTS: Shivering ceased within a mean time of 12.9 +/- 3.8 minutes in approximately 81% of the patients who received epidural butorphanol (p < 0.01), while 3% of the patients in the placebo group had no shivering following the administration of epidural saline. No sedation or changes in fetal heart rate were associated with epidural butorphanol. CONCLUSIONS: Epidural butorphanol is effective in the treatment of postepidural shivering associated with epidural lidocaine. Epidural agonist opioids have been reported to be efficacious in the management of postepidural shivering. This study demonstrated that a partial agonist opioid also is effective in the treatment of postepidural shivering.     

Pruritus--a side-effect of epidural fentanyl for postoperative analgesia

The side-effect of pruritus was studied in 31 patients receiving epidural fentanyl 100 micrograms in 8 ml normal saline for postoperative analgesia. A control group of 30 patients received pethidine 1,5 mg/kg 4-6-hourly as required. Thirteen per cent of the patients who received epidural fentanyl experienced pruritus. However, this incidence was not considered unacceptable and the pruritus was mild and of short duration.