[Spontaneous rupture of a splenic artery aneurysm during the third trimester of pregnancy]. / Rupture spontanée d'un anévrysme de l'artère splénique au cours du troisième trimestre de la grossesse.

We report the case of a 24-year-old female patient with spontaneous rupture of a splenic artery aneurysm in the third trimester of pregnancy. Pregnancy, throughout the physiological and hormonal changes it imposes, promotes the occurrence of aneurysm of the splenic artery and its rupture. Although this is a rare complication, its prognosis is severe and its typical clinical picture associating abdominal pain, hypotension and anemia is misleading for the clinician who likelier evokes a retroplacental hematoma or an uterine rupture. The maternal and foetal survival depends on rapid diagnosis and multidisciplinary management. Thus, it's important for the clinician to consider this differential diagnosis when abdominal pain or hemoperitoneum occurs in pregnant woman, particularly during the third trimester of pregnancy.

Nous rapportons l'histoire d'une patiente de 24 ans ayant présenté une rupture spontanée d'un anévrysme de l'artère splénique au cours du troisième trimestre de la grossesse. Celle-ci, de par les changements physiologiques et hormonaux qu'elle impose, favorise la survenue de l'anévrysme de l'artère splénique et sa rupture. Bien qu'il s'agisse d'une complication rare, son pronostic est redoutable et le tableau clinique typique associant douleur abdominale, hypotension et anémie est trompeur pour le clinicien qui évoque, plus volontiers, un hématome rétroplacentaire ou une rupture utérine. La survie materno-fœtale dépend de la rapidité diagnostique et d'une prise en charge multidisciplinaire, raisons pour lesquelles il est important que le clinicien considère ce diagnostic différentiel lors de la survenue d'une douleur abdominale ou d'un hémopéritoine chez la femme enceinte, particulièrement durant le 3ème trimestre de la grossesse.

Preeclampsia: an update.

Preeclampsia was formerly defined as a multisystemic disorder characterized by new onset of hypertension (i.e. systolic blood pressure (SBP) ≥ 140 mmHg and/or diastolic blood pressure (DBP) ≥ 90 mmHg) and proteinuria (> 300 mg/24 h) arising after 20 weeks of gestation in a previously normotensive woman. Recently, the American College of Obstetricians and Gynecologists has stated that proteinuria is no longer required for the diagnosis of preeclampsia. This complication of pregnancy remains a leading cause of maternal morbidity and mortality. Clinical signs appear in the second half of pregnancy, but initial pathogenic mechanisms arise much earlier. The cytotrophoblast fails to remodel spiral arteries, leading to hypoperfusion and ischemia of the placenta. The fetal consequence is growth restriction. On the maternal side, the ischemic placenta releases factors that provoke a generalized maternal endothelial dysfunction. The endothelial dysfunction is in turn responsible for the symptoms and complications of preeclampsia. These include hypertension, proteinuria, renal impairment, thrombocytopenia, epigastric pain, liver dysfunction, hemolysis-elevated liver enzymes-low platelet count (HELLP) syndrome, visual disturbances, headache, and seizures. Despite a better understanding of preeclampsia pathophysiology and maternal hemodynamic alterations during preeclampsia, the only curative treatment remains placenta and fetus delivery. At the time of diagnosis, the initial objective is the assessment of disease severity. Severe hypertension (SBP ≥ 160 mm Hg and/or DBP ≥ 110 mmHg), thrombocytopenia < 100.000/µL, liver transaminases above twice the normal values, HELLP syndrome, renal failure, persistent epigastric or right upper quadrant pain, visual or neurologic symptoms, and acute pulmonary edema are all severity criteria. Medical treatment depends on the severity of preeclampsia, and relies on antihypertensive medications and magnesium sulfate. Medical treatment does not alter the course of the disease, but aims at preventing the occurrence of intracranial hemorrhages and seizures. The decision of terminating pregnancy and perform delivery is based on gestational age, maternal and fetal conditions, and severity of preeclampsia. Delivery is proposed for patients with preeclampsia without severe features after 37 weeks of gestation and in case of severe preeclampsia after 34 weeks of gestation. Between 24 and 34 weeks of gestation, conservative management of severe preeclampsia may be considered in selected patients. Antenatal corticosteroids should be administered to less than 34 gestation week preeclamptic women to promote fetal lung maturity. Termination of pregnancy should be discussed if severe preeclampsia occurs before 24 weeks of gestation. Maternal end organ dysfunction and non-reassuring tests of fetal well-being are indications for delivery at any gestational age. Neuraxial analgesia and anesthesia are, in the absence of thrombocytopenia, strongly considered as first line anesthetic techniques in preeclamptic patients. Airway edema and tracheal intubation-induced elevation in blood pressure are important issues of general anesthesia in those patients. The major adverse outcomes associated with preeclampsia are related to maternal central nervous system hemorrhage, hepatic rupture, and renal failure. Preeclampsia is also a risk factor for developing cardiovascular disease later in life, and therefore mandates long-term follow-up.

[Obstetrical epidural analgesia and postpartum backache]. / Analgésie péridurale obstétricale et lombalgie du post-partum: un lien de cause a effet?

Backache is a common problem in the general population. The prevalence of backpain is increased during pregnancy and after delivery. Early studies have suggested that labor epidural analgesia might be associated with an increased incidence of backache in the postpartum period. However, these initial studies were retrospective and their design included several methodological deficiencies. All the prospective studies published afterwards (prospective cohort studies and 3 randomized controlled trials) yield the same result: there is no relationship between labor epidural analgesia and long-term postpartum backpain. Pregnant women must be aware of this in order to make an informed and appropriate choice about labor epidural analgesia, the most effective technique for intrapartum pain relief.

[Pseudoxanthoma elasticum and obstetric epidural analgesia: report of a case]. / Analgésie épidurale obstétricale et pseudoxanthome élastique : à propos d'un cas.

Pseudoxanthoma elasticum is a rare inherited disorder of the elastic tissue characterised by multisystem manifestations. Skin, eyes, gastro-intestinal system and cardiovascular system are the major affected systems. We describe the anaesthetic management of a parturient affected by this disease.

[Post-dural puncture headache: treatment and prevention]. / Les céphalées post-ponction durale: traitement et prévention.

Post-dural puncture headache (PDPH) is a common iatrogenic and incapacitating complication. Dural puncture can be intentional (spinal block, myelography,...) or accidental (epidural block). Risk factors are well described and the obstetric patient is at high risk for PDPH. The treatment of PDPH is not standardised. Many options have been proposed, but only the epidural blood patch has apparent benefits. A few measures have been suggested to prevent PDPH after unintentional dural puncture, but none has been shown to work with certainty.

Management of severe preeclampsia.

Features of severe preeclampsia include severe proteinuric hypertension and symptoms of central nervous system dysfunction, hepatocellular injury, thrombocytopenia, oliguria, pulmonary oedema, cerebrovascular accident and severe intrauterine growth restriction. Women with severe preeclampsia must be hospitalized to confirm the diagnosis, to assess the severity of the disease, to monitor the progression of the disease and to try to stabilize the disease. Severe preeclampsia may be managed expectantly, in selected cases. The objective of expectant management in these patients is to improve neonatal outcome. Expectant management is based on antihypertensive treatment and prevention of end organ dysfunction. Antihypertensive treatment improves maternal outcome but has the potential to be deleterious for the foetus. Plasma volume expansion has been suggested for severe preeclampsia but trials failed to show any benefit. Magnesium sulfate is the anticonvulsivant of choice to treat or prevent eclampsia when indicated. Antenatal corticosteroids are recommended in severely preeclamptic women with 26-34 weeks gestation. Timing of delivery is based upon gestational age, severity of preeclampsia, maternal and foetal risks.

Side effects of the addition of clonidine 75 microg or sufentanil 5 microg to 0.2% ropivacaine for labour epidural analgesia.

BACKGROUND: Sufentanil 5 microg and clonidine 75 microg produce a similar reduction in minimum local anaesthetic concentration of ropivacaine. The aim of the present study was to compare the side effects of two equianalgesic solutions by combining 0.2% ropivacaine with either sufentanil 5 microg or clonidine 75 microg for labour epidural analgesia. METHODS: In a prospective double-blind study, 60 women at 5 cm cervical dilatation were randomly allocated to receive 0.2% ropivacaine with either sufentanil 5 microg or clonidine 75 microg to initiate labour analgesia. The analgesic efficacy and side effects of the two mixtures were compared. RESULTS: Onset, duration and quality of analgesia and subsequent ropivacaine consumption were similar in the two groups. Hypotension was significantly more frequent and severe with clonidine than with sufentanil (systolic blood pressure <100 mmHg: 17/26 vs. 6/24, P <0.05; systolic blood pressure <90 mmHg: 5/26 vs. 0/24, P <0.05) resulting in more frequent ephedrine administration (11/26 vs. 2/24, P <0.05) and larger fluid requirements (1696 +/- 583 mL vs. 1264 +/- 407 mL, P < 0.05). Conversely, pruritus was more frequent with sufentanil than with clonidine (6/26 vs. 1/24, P <0.05). CONCLUSIONS: Hypotension occurs more frequently when clonidine is added to epidural ropivacaine instead of an equianalgesic dose of sufentanil. Therefore, clonidine cannot be recommended for routine administration for labour epidural analgesia.

[Circulatory and respiratory problems in preeclampsia]. / Manifestations hémodynamiques et respiratoires de la prééclampsie.

The hemodynamic and cardiovascular changes seen during PE vary according to the natural history of the disease, its severity and eventual therapeutic measures taken. In the early stages of pregnancy, patients who will eventually develop PE, present with a blood pressure which even though within normal limits, is higher than in other women. Similarly, their cardiac output is higher with a normal or decreased peripheral vascular resistance. As soon as the clinical signs of the disease appear, the hemodynamic picture usually shifts toward that of a high peripheral resistance with low cardiac output. Sometimes however, a clinically hyperkinetic circulation may be demonstrated. In PE patients, cardiac preload pressures are usually normal even though the circulatory volumes are lower by 600 to 800 ml when compared to those found in normal pregnancy. The cardiac function is however usually preserved during PE. PE induces an exaggerated capillary permeability. This results in the worsening of the airway edema which may render the intubation very difficult. The increased capillary permeability contributes, among other factors, to the heightened risk of acute pulmonary edema. It is not justified to administer an anti-hypertensive treatment to PE women presenting with only moderate hypertension. An anti-hypertensive treatment must only be initiated whenever the hypertension is severe (i.e. SBP> or =160 mmHg and/or DBP> or =110 mmHg) in order to reduce the risk of maternal complications. In the absence of objective comparative data assessing anti-hypertensive agents for the PE patient, the choice of therapy relies predominantly on the practitioners' own experience. Systematic circulatory volume expansion has not been proven to improve the maternal nor the neonatal prognosis. Such treatment is to be reserved solely for situations in which correcting a hypo-volemia is absolutely necessary. The treatment of acute pulmonary edema in a PE patient is symptomatic and includes the administration of vasodilating agents and of diuretics. A benefit in setting-up an invasive monitoring of the pulmonary artery occlusive pressure has not been demonstrated. The sonographic surveillance of the hemodynamic state can however be useful in these circumstances.

[Is a coagulation blood test compulsory before neuraxial blockade for labor analgesia?]. / Faut-il prescrire systématiquement un bilan d'hémostase avant la réalisation d'une péridurale analgésique pour le travail en obstétrique?

Neuraxial blockade such as epidural, spinal or combined spinal-epidural analgesia is considered to be the best technique for labour analgesia. Even if epidural hematoma is a very rare complication of neuraxial blockade, it may result in severe and definitive neurological injuries. This rare complication is usually associated with coagulation abnormalities. This is the reason why many physicians order routine coagulation screening tests before performing neuraxial blockade. This practice is questionable from the evidence-based medicine and the economic point of view. According to the guidelines published by several scientific societies, no routine coagulation screening tests are required in the absence of any history or clinical suspicion of coagulation impairment. The aim of the present article is to delineate the appropriate attitude in this context.

[Treatment of severe preeclampsia: until when and for what risks/benefits?]. / Traitement de la prééclampsie sévère: jusqu' où, et pour quels risques/bénéfices?

The four major hypertensive disorders related to pregnancy are preeclampsia, chronic hypertension, preeclampsia superimposed upon chronic hypertension, and gestational hypertension. The development of hypertension and proteinuria in pregnancy is usually due to preeclampsia, particularly in a primigravida. These findings typically become apparent in the latter part of the third trimester and progress until delivery, but some women develop symptoms in the latter half of the second trimester, or intrapartum, or the early postpartum period. Preeclampsia is characterized as mild or severe. Severe hypertension, coagulopathy, thrombocytopenia, liver function abnormalities, and fetal growth restriction are features of severe disease. Laboratory evaluation should assess haemoglobin/hematocrit and platelet count, renal and hepatic function, as well as assessment of fetal well-being and growth. Timing of delivery is based upon gestational age, maternal and fetal condition, and the severity of preeclampsia. Maternal end organ dysfunction and nonreassuring tests of fetal well-being are indications for delivery at any gestational age. Antihypertensive treatment aims at protecting the mother from severe hypertensive encephalopathy, but may jeopardize the fetus. We recommend antenatal corticosteroids (betamethasone) be given to women with preeclampsia at 26 to 34 weeks of gestation. Magnesium sulfate is more effective than phenytoin for prevention of eclamptic seizures.

Impact of the addition of sufentanil 5 microg or clonidine 75 microg on the minimum local analgesic concentration of ropivacaine for epidural analgesia in labour: a randomized comparison.

BACKGROUND: Addition of lipophilic opioids or alpha2-agonists to local anaesthetic solutions reduces local anaesthetic requirements and side effects. While the efficacy and side effects of these adjuvants are dose-related, information about their relative analgesic potencies is lacking, making it difficult to draw meaningful clinical conclusions. The aim of the present study was to assess the relative sparing of ropivacaine by clinically relevant doses of sufentanil and clonidine using the minimum local analgesic concentration (MLAC) model. METHODS: In this prospective, double-blind study, the sparing effect of sufentanil 5 microg and clonidine 75 microg on the MLAC of ropivacaine administered for labour epidural analgesia was compared in 78 women at <5 cm cervical dilatation. Women were randomly allocated to one of three groups: plain ropivacaine, ropivacaine with sufentanil 5 microg and ropivacaine with clonidine 75 microg. RESULTS: The MLAC of plain ropivacaine was 0.099% wt/vol (95%CI: 0.090 to 0.109) and was reduced to 0.036% wt/vol (95% CI: 0.024 to 0.049) when combined with sufentanil 5 microg and to 0.036% wt/vol (95% CI: 0.027 to 0.046) with clonidine 75 microg (P < 0.001). The wt/wt local anesthetic sparing potency ratio of sufentanil to clonidine was 15.1 (95% CI: 10.3 to 23.4). CONCLUSIONS: Sufentanil 5 microg and clonidine 75 microg produce similar reductions in the MLAC of ropivacaine. This finding will make feasible the assessment of the side effects of these adjuvants administered at equipotent doses in further studies.

Effect of an intubation dose of rocuronium on Spectral Entropy and Bispectral Index responses to laryngoscopy during propofol anaesthesia.

BACKGROUND: The spectral entropy of the electroencephalogram has been proposed to monitor the depth of anaesthesia. State Entropy (SE) reflects the level of hypnosis. Response Entropy (RE), computed from electroencephalogram and facial muscle activity, reflects the response to nociceptive stimulation. We evaluated the effect of rocuronium on Bispectral Index (BIS) and entropy responses to laryngoscopy. METHODS: A total of 25 patients were anaesthetized with propofol using a target-controlled infusion. At steady state, they randomly received 0.6 mg kg(-1) rocuronium (R) or saline (S). After 3 min, a 20 s laryngoscopy was applied. BIS, RE and SE were recorded continuously and averaged over 1 min during baseline, at steady state, 2 min after R or S administration (R/S+2) and 0, 1, 2 and 3 min after laryngoscopy (L0, L1, L2, L3). RESULTS: At R/S+2, the RE-SE gradient was higher in Group S than in Group R. Laryngoscopy provoked an increase in BIS, RE and SE. Comparing R/S+2 and L0 values in Groups R and S, BIS increased from 43 (6) to 49 (8) and 42 (9) to 51 (15), SE increased from 43 (7) to 50 (8) and 41 (10) to 55 (12), and RE increased from 46 (8) to 54 (9) and 47 (12) to 66 (15), respectively. BIS and SE did not differ between groups. At L0, RE and RE-SE were higher in Group S [66 (15) and 11 (4), respectively] than in Group R [54 (9) and 4 (2), respectively]. CONCLUSIONS: Rocuronium alters the RE-SE gradient and the RE and RE-SE responses to laryngoscopy. Muscle relaxation may confound interpretation of entropy monitoring.

Blood glucose concentration profile after 10 mg dexamethasone in non-diabetic and type 2 diabetic patients undergoing abdominal surgery.

BACKGROUND: Dexamethasone prevents postoperative nausea and vomiting but may increase blood glucose. We compared blood glucose concentrations after dexamethasone in non-diabetic and type 2 diabetic patients undergoing surgery and looked for any association with preoperative glycosylated haemoglobin [HbA (1c)] and BMI. METHODS: Sixty three patients were enrolled: 32 were non-diabetic (Group ND) and 31 type 2 diabetic (Group D) without insulin treatment. Anaesthesia was induced using i.v. anaesthetic agents and maintained with sevoflurane. All patients received 10 mg dexamethasone at induction. Blood glucose concentrations were measured at induction and then every 60 min for 240 min. Data were analysed using anova. Effects of HbA (1c) and BMI were investigated using linear correlation and logistic regression. RESULTS: Blood glucose concentrations increased significantly over time and peaked at 120 min after 10 mg dexamethasone in both groups. The magnitude of increase was comparable between the groups [mean (SD) 29 (19) and 35 (19)% of baseline in Group D and Group ND, respectively]. Maximum concentrations were higher in Group D [8.97 (1.51) mmol litre(-1), range 6.67-12.94 mmol litre(-1)] than in Group ND [7.86 (1.00) mmol litre(-1), range 5.78-10.00 mmol litre(-1)]. There was a significant correlation between the maximum concentrations and BMI (R(2)=0.21) or HbA (1c) (R(2)=0.26). Logistic regression analysis revealed that the higher the BMI, the lower the HbA (1c) threshold associated with an increased probability (>0.5) of observing blood glucose levels higher than 8.33 mmol litre(-1) during 240 min after dexamethasone administration. Similarly, the higher the HbA (1c), the lower the BMI threshold associated with the same probability. CONCLUSIONS: After 10 mg dexamethasone, blood glucose levels increase in non-diabetic and type 2 diabetic patients undergoing abdominal surgery. Poorly controlled diabetes and severe obesity can influence the development of hyperglycaemia.

Combined use of Bispectral Index and A-Line Autoregressive Index to assess anti-nociceptive component of balanced anaesthesia during lumbar arthrodesis.

BACKGROUND: This study evaluated the A-Line Autoregressive Index (AAI) response to surgical stimulation during lumbar arthrodesis, as an estimate of the anti-nociceptive component of a Bispectral Index (BIS) guided anaesthesia combined with epidural analgesia. METHODS: An epidural catheter was inserted in 23 patients allocated randomly to receive ropivacaine plus clonidine (Group R) or normal saline (Group S) epidurally. General anaesthesia was induced with propofol, cis-atracurium and a remifentanil infusion that was stopped 3 min after tracheal intubation, and maintained using sevoflurane to keep BIS at 50 (range 40-60). Mean arterial pressure, heart rate, end-tidal sevoflurane, BIS and AAI were analysed from 2 min before to 17 min after surgical incision. RESULTS: While BIS was maintained at 50, AAI significantly increased from a 2 min averaged value of 12 (4) to 21 (7) in Group S within the first 5 min after surgical incision, but did not change in Group R. Maximum AAI values reached during the study period were significantly higher in Group S than in Group R [38 (12) and 27 (10), respectively]. Binary logistic regression analysis allowed the calculation of AAI threshold values above which the probability of predominant nociception over anti-nociception was higher than 95%. At 1 MAC sevoflurane concentration, a 2 min averaged AAI of 35 or an AAI peak value of 62 were associated with such a probability. CONCLUSIONS: During a BIS-guided constant level of hypnosis, AAI response to the onset of surgical stimulation significantly differs according to the analgesic regimen. Further studies are needed to refine the estimation of sensitivity and specificity of this variable in assessing the balance between nociception and anti-nociception during general anaesthesia.

Effects of nitrous oxide on spectral entropy of the EEG during surgery under balanced anaesthesia with sufentanil and sevoflurane.

BACKGROUND: Spectral entropy of the electroencephalogram (EEG) has been proposed to monitor anaesthetic depth. We investigated the effect of nitrous oxide on response (RE) and state entropy (SE) of the EEG during lumbar disc surgery under anaesthesia with sufentanil and sevoflurane. METHODS: In an open study, anaesthesia was induced with propofol and sufentanil, and maintained with 2% end-tidal sevoflurane concentration in air/oxygen (FiO2 = 0.4) in 25 patients. During surgery, nitrous oxide was randomly administered either at 0 or at 60% end-tidal concentration in 10 (control group) and 15 patients (nitrous oxide group), respectively. RE and SE were recorded at 2.5 min intervals for 10 min before randomization and for 25 min either continuously (control) or after achieving the target nitrous oxide concentration. RESULTS: Two patients who received nitrous oxide were excluded from statistical analysis because of protocol violation. Nitrous oxide provoked a significant decrease in RE and SE from 46.2 +/- 11.1 and 44.3 +/- 11.1 to a lowest value of 27.8 +/- 8.3 and 27.1 +/- 8.9, respectively. The decrease in entropy persisted during the 25 min recording period. CONCLUSIONS: Addition of nitrous oxide during balanced anaesthesia with sufentanil and sevoflurane provokes a decrease in response and state entropy of the EEG during lumbar disc surgery.

Comparative effects of ketamine on Bispectral Index and spectral entropy of the electroencephalogram under sevoflurane anaesthesia.

BACKGROUND: The Bispectral Index (BIS) and spectral entropy of the electroencephalogram can be used to assess the depth of hypnosis. Ketamine is known to increase BIS in anaesthetized patients and may confound that index as a guide to steer administration of hypnotics. We compared the effects of ketamine on BIS, response entropy (RE) and state entropy (SE) during surgery under sevoflurane anaesthesia. METHODS: Twenty-two women undergoing gynaecological surgery were enrolled in this double-blind, randomized study. Anaesthesia was induced i.v. and maintained with sevoflurane. Under stable surgical and anaesthetic conditions, patients were assigned to receive either a bolus of ketamine 0.5 mg kg(-1) or the same volume of saline. Blood pressure, heart rate, BIS, RE and SE were measured every 2.5 min from 10 min before (baseline) until 15 min after ketamine or saline administration. The maximum relative increase in BIS, RE and SE compared with baseline was calculated for each patient. Values are mean (sd). RESULTS: Baseline values were BIS 33 (4), RE 31 (5), SE 30 (5) for the ketamine patients and BIS 35 (3), RE 33 (5) and SE 32 (6) for the patients receiving saline. BIS, RE and SE increased significantly from 5 min (BIS) and 2.5 min (RE and SE) after ketamine administration, peaking at 46 (8) (BIS), 52 (12) (RE) and 50 (12) (SE) respectively. The maximum relative increase in RE [42.2 (10.4%)] and SE [41.6 (10.9)%] was higher than that of BIS [29.4 (10.4%)]. Blood pressure, heart rate and RE-SE gradient did not change in either group. CONCLUSIONS: Ketamine administered under sevoflurane anaesthesia causes a significant increase in BIS, RE and SE without modification of the RE-SE gradient. This increase is paradoxical in that it is associated with a deepening level of hypnosis.

Recovery from neuromuscular block after an intubation dose of cisatracurium and rocuronium in lumbar disc surgery.

BACKGROUND AND OBJECTIVE: Residual muscle paralysis remains a concern for anaesthesiologists. This study investigated the recovery from neuromuscular block (NMB) after an intubation dose of cisatracurium (C) or rocuronium (R) in 32 patients undergoing lumbar disc surgery. METHODS: Anaesthesia was induced with propofol and sufentanil, and maintained with sevoflurane in nitrous oxide/oxygen. Patients were randomised to receive twice the ED95 of either cisatracurium (GC) or rocuronium (GR) before tracheal intubation. After placement in prone position, neuromuscular transmission was monitored at the wrist by accelerometry. NMB was antagonised when the TOF ratio (TOFR) was < 0.75 at muscle closure. The time from muscle relaxant to muscle closure, and to TOFR of 0.25 and of 0.50 were recorded. Data were analysed using Student's t-tests, chi-squared tests and two-way mixed-designed ANOVA's. The prediction probability (Pk) of the times from muscle relaxant to muscle closure, and to TOFR of 0.25 for the necessity to antagonize NMB was calculated in both groups. P < 0.05 was considered statistically significant. RESULTS: NMB was antagonized in 8 (GC) and 6 (GR) patients, respectively. The time from muscle relaxant to muscle closure was shorter in patients whose NMB was antagonized. The Pk of this time was significant in GC (0.85) but not in GR (0.69). In GR contrarily to GC, the times to a TOFR of 0.25 and 0.50 were longer in patients whose NMB was antagonized. The Pk of the time to TOFR of 0.25 was significant in GR (0.95) but not in GC (0.64). CONCLUSIONS: A single dose of cisatracurium or rocuronium may be associated to some degree of NMB at the end of lumbar surgery, depending on the duration of surgery and on the duration of action of the muscle relaxant which is more variable for rocuronium than for cisatracurium.