Respiratory depression during epidural morphine treatment

An 81-year-old woman was treated for 2 weeks with systemic opioids and for 2 days with epidural morphine before a severe and prolonged respiratory depression occurred.     

全麻术后意识恢复呼吸抑制原因探讨

目的探讨择期手术全身麻醉术后患者经麻醉医师评估后拔除人工气道,在麻醉恢复监测过程中出现呼吸抑制重建人工气道的原因,提出预防与处理措施。方法回顾2012年3月-2014年3月由麻醉科送入重症医学科的择期全身麻醉术后患者2209例,对其中6例已拔除人工气道患者在入住重症医学科后5-20min内出现呼吸抑制并重建人工气道患者的原因进行分析。结果全麻术后患者意识恢复拔除人工气道后,出现呼吸抑制及气道梗阻与患者年龄、体重指数、手术时间短、全麻药及肌松药残留、气道高反应性等因素相关。结论全麻术后意识恢复不是拔除人工气道的主要指征;气道高危患者可适当延迟拔除人工气道;术后适当应用拮抗剂可减少全麻术后呼吸抑制并发症。     

Respiratory depression following postoperative analgesia with epidural morphine

Eighteen healthy patients subjected to operation for duodenal ulcer were allocated randomly to one of two regimes of analgesic treatment with epidural morphine. The analgesic regime was started either per- or postoperatively. Epidural morphine in doses of 4 mg was given until satisfactory pain relief was achieved. PaCO2 and respiratory rate were measured hourly for 10 h and a nearly identical respiratory depression was found in the two groups. Peak PaCO2-values were seen in the 5th and 6th postoperative hour. The respiratory rate was initially high and declined during the first postoperative hours. Only one patient in each group had a pathologically low respiratory rate (8 min-1), but this was transient and seen in the 10th postoperative hour. The needs for epidural morphine on the first postoperative day were highest in the peroperative group. It is concluded that a peroperative start of pain treatment with epidural morphine does not affect the degree of respiratory depression or reduce the postoperative analgesic requirements.     

Spinal epidural hematoma following epidural catheter removal during antiplatelet therapy with cilostazol

A 90-year-old man underwent emergency thrombectomy for acute occlusion of the right femoral and popliteal arteries. After an epidural catheter (used for intraoperative/postoperative management) was removed, a spinal epidural hematoma involving the Th12 to L3 areas developed. Emergency removal of the hematoma and decompression of the spinal cord were performed. Possibly, the hematoma had developed due to therapy with an antiplatelet agent, cilostazol, which had been started on the first postoperative day, and due to the removal of the catheter, on the third postoperative day, in addition to the patient's advanced age. This case may be the first report of spinal epidural hematoma associated with both cilostazol and epidural anesthesia. From the time course in this patient, important knowledge of drug actions and follow-up may be gained for determining the timing of catheter removal in a patient receiving antiplatelet therapy with cilostazol.     

Intramedullary pneumorrhachis following a cervical epidural steroid injection

Pneumorrhachis (PR) is a rare radiological condition characterized by the presence of intraspinal air. PR is commonly classified as spontaneous (nontraumatic), traumatic, or iatrogenic, and iatrogenic PR is the most common and often occurs secondary to invasive procedures such as epidural anesthesia, lumbar puncture, or spinal surgery. PR is usually asymptomatic, but it can produce symptoms associated with its underlying pathology. Here, we report a rare case of intramedullary cervical PR following a cervical epidural steroid injection (ESI) and include pertinent discussion.     

硬膜外小剂量吗啡中枢呼吸调节抑制效应的临床观察

观察了５０例无心、肺疾患，ＡＳＡⅠ～Ⅱ级的子宫或卵巢部分或全切除的患者术后硬膜外注射 ２．５ｍｇ吗啡的 ＣＯ２通气反应、止痛效应、脉搏氧饱和度（ＳＰＯ２）和呼出气ＣＯ２分压（ＰＥＴＣＯ２）变化。硬膜外注药后 １、３、６、９和 １２小时的ＣＯ２通气反应值，分别自术前８５７３（均值）降至 ５ ５１３、３ ９４５、３３９８、４２６８和 ５ ２３５１ｍｌ· ｋＰａ－１· ｍｉｎ－１。最大降低值发生在注药后 ６小时有２９例，３小时１１例，９小时１０例。 ４例于注药后１４５～４５０分钟ＳｐＯ２降至９２％～９５％，１５例ＰＥｒＣＯ２于注药后１００～４８０分升达６．１３～７．２０ｋＰａ．而呼吸频率无明显改变。呕吐（４４％）和困倦（１６％）发生在注药后８０～１００分。认为硬膜外小剂量吗啡的中枢呼吸调节抑制作用主要发生在用药后３～９小时。但因有较大个体差异，临床上监测呕吐、困倦、 ＰＥＴＣＯ２和 ＳｐＯ２变比应持续１２小时     

Respiratory depression following epidural morphine in an infant of three months of age

Epidural administration of combinations of opioids and a local anaesthetic provides prompt and effective analgesia and is increasingly used in paediatric anaesthesia. However, respiratory depression by rostral spread of opioid in the CSF is by far the greatest concern after epidural morphine. An infant of three months of age underwent portoenterostomy (Kasai's operation) for extrahepatic biliary duct atresia. A median approach at the L₃–L₄ epidural interspace was used and a dose of 1 ml·kg^–1 of 0.125% bupivacaine with adrenaline 1:400 000 mixed with 50 μg·kg^–1 morphine was injected using a 19 gauge Tuohy needle. Six h after epidural morphine, the infant developed respiratory depression with an increase in drowsiness, miosis and decreased respiratory rate. Low arterial saturation ( S pO₂) was detected by pulse oximetry and confirmed by blood gas analysis. An intravenous bolus of 5 μg·kg^–1 naloxone followed by a 3-h infusion of 2 μg·kg^–1·h^–1 resulted in complete reversal of signs and symptoms of respiratory depression. Epidural opioids should be limited to paediatric patients admitted to specialized recovery units for the first postoperative day.     

Respiratory depression following epidural morphine: a clinical study

Thirteen post-thoracotomy patients were entered into a double-blind, randomized clinical trial comparing the effects of epidural morphine (Group E) and intravenous morphine (Group I) on postoperative respiratory depression. Postoperative respiratory depression was assessed for 24 hours by (a) PaCO2 at 2, 6, 12 and 24 hours (b) hourly assessment of respiratory rate (RR) (c) presence of respiratory rate of less than ten breaths per min for greater than 5 min (SRR) (d) hypopnoea/apnoea (H/A). RR, SRR, and H/A were measured using respiratory inductive plethysmography. PaCO2 was significantly elevated at 2, 6 and 12 hours in Group E and only at two hours in Group I. One of five patients in Group I had a single episode of SRR whereas five of eight patients in Group E had multiple episodes of SRR. None of the patients in Group I had H/A episodes, in contrast to six of eight in Group E who had numerous H/A episodes post-operatively. This difference was statistically significant. Multiple doses of epidural morphine produce an insidious and unpredictable change in respiratory pattern. Electronic monitoring is useful to assess those at risk of overdose and possible respiratory arrest.     

Spinal anesthesia for cesarean section following inadequate labor epidural analgesia: a retrospective audit

BACKGROUND: High blocks have been reported when spinal anesthesia is used for cesarean section following inadequate labor epidural analgesia. We have therefore modified the practice at our institution to minimize this risk and conducted a retrospective observational study of outcome following the change of practice. METHOD: The records of 115 women with inadequate epidural labor analgesia who required cesarean section between July 1998 and January 2002 were studied. No epidural boluses were administered in the 30 min preceding spinal anesthesia and a reduced spinal dose, median (range) 9.38 mg (7.5-11.3 mg) of 0.75% hyperbaric bupivacaine and fentanyl 15 microg (10-25 microg) was used. Patients were left sitting for 2 min and then positioned supine with left uterine displacement and were closely monitored for symptoms or signs that would suggest a high block. RESULTS: No parturient developed a high spinal necessitating intubation, and there was no adverse neonatal outcome. CONCLUSION: These findings do not conclusively establish this method as safe, but should spinal anesthesia for cesarean section following suboptimal labor epidural analgesia be considered, avoiding epidural boluses immediately preceding spinal injection, using a lower spinal dose, and delayed supine positioning following spinal injection may be advisable.     

Evaluation of levobupivacaine passage to breast milk following epidural anesthesia for cesarean delivery

BackgroundFollowing maternal administration, local anesthetics pass into breast milk. In the present study, we aimed to compare the passage of levobupivacaine and bupivacaine into breast milk following epidural anesthesia for cesarean delivery.MethodsA total of 20 women undergoing elective cesarean delivery under epidural anesthesia were randomized to receive either 0.5% levobupivacaine or 0.5% racemic bupivacaine via an epidural catheter. Immediately before and 30 min, 1 h, 2 h, 6 h, 12 h and 24 h after administration of epidural local anesthetic, maternal blood and breast milk samples were taken simultaneously. Drug concentrations in plasma and milk were determined via high-performance liquid chromatography. The infant’s drug exposure was determined by calculating milk/plasma ratios of levobupivacaine and bupivacaine.ResultsBoth levobupivacaine and bupivacaine were detected in breast milk 30 min after epidural administration. Concentrations of both agents showed constant and similar decreases in milk and plasma and were nearly undetectable at 24 h. The milk/plasma ratios were 0.34 ± 0.13 for levobupivacaine and 0.37 ± 0.14 for bupivacaine.ConclusionsBoth levobupivacaine and bupivacaine pass into breast milk following epidural administration. The concentration of both drugs was approximately three times lower in breast milk than in maternal plasma.     

钢丝加强聚脲胺酯硬膜外导管减少硬膜外出血发生率

目的 比较钢丝加强聚脲胺酯与聚氯乙烯硬膜外导管对硬膜外腔出血发生率的影响. 方法 150例拟行连续硬膜外或蛛网膜下腔-硬膜外联合阻滞患者,按随机数字表法分为聚氯乙烯硬膜外导管组(A组,n=75)和钢丝加强聚脲胺酯硬膜外导管组(B组,n=75),以阻力消失作为判断硬膜外针到达硬膜外腔的标志,记录放置硬膜外导管遇到阻力和同抽出血情况.追踪术后1周有无硬膜外血肿发生. 结果两组间性别、年龄、体重等差异无统计学意义(P>0.05). A组和B组未遇到明显阻力分别为42.7%和78.6%,遇到轻微阻力分别为48.0%和16.0%;遇到阻力较大,放入导管困难分别为9.3%和5.4%,组间比较差异有统计学意义(P<0.01).A组无回血为82.6%,有不连续回血率为10.7%,有连续回血率为6.7%;B组无回血率为100%,组间比较差异有统计学意义(P<0.01).两组术后均无硬膜外血肿压迫症状的并发症.结论 聚氯乙烯硬膜外导管损伤硬膜外血管引起出血为常见并发症,采用钢丝加强聚脲胺酯硬膜外导管可显著减少硬膜外出血发生率.     

Lumbar epidural block reduces cough strength in healthy young subjects

Effects of lumbar epidural block on maximum expiratory strength were studied in 12 healthy volunteers. Subjects performed maximum expiratory effort against occluded airway at functional residual capacity (FRC) and total lung capacity (TLC) while measuring airway pressure and electromyogram of the abdominal muscles (EMGab). Cough strength was assessed by maximum expiratory pressure (PE_max) and peak EMGab (peak-EMGab). Following injection of 2% lidocaine 17.8±1.1 ml into the lumbar epidural space (L2.3±0.4), upper levels of analgesia ranged from T11 to T4 (T7.8±1.3). Peak-EMGab and PE_max were significantly reduced by lumbar epidural block at both lung volumes. Compared with severe reduction in peak-EMGab, PE_max was well maintained at TLC, but changes in PE_max were identical to those in peak-EMGab at FRC. When analgesia spread to higher than T6, PE_max at TLC decreased considerably. We conclude that lumbar epidural block producing analgesia above T6 paralyzes the abdominal muscles and severely impairs the ability of effective cough in healthy young men.     

Incidence of respiratory depression after epidural administration of morphine for cesarean delivery: findings using a continuous respiratory rate monitoring system

BackgroundEpidural morphine is widely used for postoperative analgesia after cesarean delivery. However, respiratory depression can occur after neuraxial administration of morphine. Previous reports describing respiratory depression in obstetric patients have relied on intermittent visual counting of the respiratory rate. In this study, we estimated the incidence of respiratory depression in patients who had received epidural morphine after cesarean delivery, using a continuous respiratory rate monitoring system with a finger sensor.MethodsOne hundred patients scheduled to undergo elective cesarean delivery and receive intraoperative neuraxial morphine between April and December 2016 were recruited for this single-center, prospective observational study. Postoperatively, all patients received epidural morphine 3 mg and were equipped with the Nellcor respiratory rate monitoring system. Respiratory depression was defined as both bradypnea (respiratory rate ≤10 breaths/min) and oxygen desaturation (mild ≤95%; moderate ≤90%; severe ≤85%) for longer than one minute. The number of patients with respiratory depression between administration of morphine and first ambulation was recorded hourly.ResultsComplete monitoring was obtained for 89 of 100 women. The median duration of monitoring was 19.0 hours. Forty-six patients (52%) developed mild respiratory depression at least once before ambulation, but only one (1%) developed moderate respiratory depression. None required supplemental oxygen or naloxone.ConclusionsApproximately half the women experienced mild respiratory depression, but only one developed moderate respiratory depression. Continuous respiratory rate monitoring until ambulation may assist in early identification of respiratory depression after neuraxial administration of morphine.     

Meningitis por Enterococcus faecium secundaria a anestesia epidural. A propósito de un caso y revisión de la literatura

Septic meningitis secondary to epidural anesthesia is a rare but serious complication that is usually related to exogenous contamination from inadequate aseptic techniques, so the most frequent microorganisms observed are S. aureus and S. salivarius. We describe the case of a woman who, after receiving epidural anesthesia for normal delivery, presented septic meningitis due to E. faecium with recurrence after antibiotic treatment, probably secondary to pyogenic ventriculitis undetected in the first episode.We highlight the rarity of the case, emphasizing the need for strict aseptic technique, and review the literature on the most appropriate treatment for this type of complication.