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Alexandria Journal of Anaesthesia and Intensive Care 11 Plain Versus Hyperbaric Ropivacaine for Spinal Anesthesia in Cirrhotic Patients Undergoing Ano-rectal Surgery Essam A. Eid MD*, Faisal AlSaif. FRCS, AB** *Associate Prof.Anesthesiology, King Saud University, KSA Assist. Prof. Anesthesiology, National Liver Institute, Menoufia University, Egypt **Assist. Prof., Head of Hepatobiliary Unit, KKUH, Riyadh, KSA Background: In cirrhotic patients undergoing ano-rectal surgery, spinal anesthesia/analgesia remains a challenge. Coagulopathy and intraoperative hypotension represent a major challenge for the anesthetist during spinal anesthesia in those patients. This study was designed to examine the efficacy and the adverse effects of ropivacaine (plain, hyperbaric) spinal anesthesia for anorectal surgery in cirrhotic. Material and Methods: Forty known cirrhotic patients categorized as Child-A, scheduled for anorectal surgery under spinal anesthesia were enrolled in this study. Patients were randomly allocated into 2 equal groups. Patients received 2.0 ml ropivacaine 0.6% (6 mg/ml), either in plain solution (group I) or with glucose (hyperbaric) group II. 10µg fentanyl was added for each solution. The extent and duration of sensory and motor block, pulse rate, blood pressure, and time to mobilization were recorded. Any unwanted effects related to spinal blockade were also recorded. Results: There were significant differences in median time to onset of sensory block at T10 (plain 9 min; hyperbaric 3 min; P<0.01), median maximum extent (plain T8; hyperbaric T6; P<0.05), and median duration of sensory block at T10 (plain 66 min; hyperbaric 113 min; P<0.01). However, median times to complete regression of both sensory (183 vs 156 min; P<0.05) and motor (158 vs 123 min; P<0.05) block were longer in the plain group. Patients mobilized sooner in the hyperbaric group (plain 192 vs hyperbaric 131 min; P<0.01). All the hyperbaric blocks were adequate for surgery, but three patients receiving plain ropivacaine required sedative/analgesic bolus during anal dilatation. Conclusion: The practice of spinal anesthesia in patients with mild cirrhosis is a safe and reliable anesthetic technique. Addition of glucose 50 mg/ml to plain ropivacaine 6% increases the speed of onset, block reliability, duration of useful block for ano-rectal surgery, and speed of recovery. Moreover hemodynamic stability is a prominent feature of that block. nal surgery in patients with normal liver function and having the criteria of American society of anesthologist (ASA) class I and II, represent one of the commonest ambulatory procedures that carried out every day in every hospital with perioperative morbidity of 0.0-0.05 %(1). However, "Child A" cirrhotic patients, although they have normal coagulation profiles, may develop serious alterations in coagulation with deranged hepatic function during the perioperative period(2). Moreover, general anesthesia remains a challenge, mainly because of the small range between the therapeutic effect and side effects (limited therapeutic index) of conventional opioids, hypnotics and muscle relaxants given intravenous (IV). Those patients have altered multiple neurotransmitter systems, such as gamma-aminobutyric acid (GABA ergic), glutamatergic, and opioidergic, which A make the anesthetic outcome unpredictable(3). Experimental studies have shown that opioidergic neurotransmission (such as µ and δ-receptors) may be altered in cirrhotic patients, selectively increasing receptor affinity for opioids. The exogenous or endogenous stimulation of these receptors may lead to impaired mental function(4). The use of the spinal/epidural route has proven very effective in the postoperative care of high-risk patients. However, the possibility of a bloody tap from needle or catheter placement or continuing trauma due to the presence of an epidural catheter has been widely described and may occasionally result in spinal bleeding. Although epidural hematoma is a rare event, it is always recorded in relation to deranged haemostatic capacity or complete anticoagulation(5). While, Child-A cirrhotic patients had a normal coagulation state, there is lack of researches about spinal AJAICAJAIC-Vol. (10) No. 1 Marsh 2007 Alexandria Journal of Anaesthesia and Intensive Care anesthesia in those patients and the behavior of them during the stress of the perioperative period. Spinal anesthesia with short acting local anesthetic i.e. lidocaine, was the most useful choice for anorectal procedures in the ambulatory surgery setting(1). However, since 1993 when Schneider et al(6) described severe radicular back pain, now termed transient neurological symptoms (TNS) after hyperbaric lidocaine spinal anesthesia, its use in ambulatory surgery have been reviewed. Preliminary work has shown that ropivacaine provides spinal anesthesia of shorter duration and less motor blockade than bupivacaine, and may be of particular interest in the day-case setting(7). However, there are few data comparing the actions of plain and hyperbaric solutions of this drug. Early studies of glucose-free (plain) ropivacaine found that intrathecal injection produced a sensory block of very variable extent, and a large proportion of patients required general anesthesia because of inadequate distribution of block, mainly, but not exclusively, in the patients receiving 10 mg and less(8). Since then, other studies have shown that plain ropivacaine can produce satisfactory analgesia for surgery, but doubt remains about its reliability, as is the case with other agents in plain solution(7,8). Two recent studies of hyperbaric ropivacaine (10 mg) have shown that it produces predictable and reliable anesthesia for surgery and with a duration that is shorter than that of bupivacaine(9,10). Saddle shaped spinal anesthesia has been recommended as the ideal anesthetic technique for ano-rectal surgery. Saddle block found to be associated with minimal intraoperative hypotension, fluid requirements and rapid recovery and discharge times(1). In the present study, lowlumbar approach for spinal block has been used instead of saddle block, to allow clinical comparison of plain ropivacaine versus hyperbaric. Fentanyl is increasingly being used as adjuncts to local anesthetics. It enhances spinal anesthesia without prolonging motor recovery and discharge time. It is of less lipid solubility compared to sufentanil, make it of modest spinal selectivity ; gave favorable analgesia in few minutes, for 12 modest duration (1-4 hours) and little risk of respiratory depression(11). The addition of fentanyl to plain and hyperbaric ropivacaine increased equally the intraoperative quality of spinal anesthesia in obstetric and nonobstetric patients(12). Intrathecal fentanyl is sometimes accompanied by adverse effects such as pruritus, nausea and occasionally urine retention with delay of the discharge of patients(13). The best risk-benefit dose of intrathecal fentanyl ranged from 10 to 25 µg(11). This study was designed to examine the efficacy and the adverse effects of 12 mg ropivacaine (plain, hyperbaric)-fentanyl low lumbar spinal anesthesia for anorectal surgery in cirrhotic. METHODS This randomized controlled, double blind study was approved by the local ethical hospital committee and informed consent was obtained from each patient. Forty patients who were ASA physical status II-III, aged 18 yr or older, scheduled for elective ano-rectal surgery were enrolled in the study. All patients were known to have liver cirrhosis of Child-Pugh classification grade –A. They were under medical treatment (vitamin K, K+- sparing diuretics, IV albumin, β-blockers (Inderal), which continued in the perioperative period. Exclusion criteria included patients of ChildPugh Score of grade B and C, those with INR ratio > 1.5, patients who had chronic analgesia therapy, scoliosis, and history of previous back surgery, diabetes, or peripheral neuropathies. Patients received no premedication. Upon arrival to the operating room, an IV cannula was secured under local anesthesia and IV NaCl 0.45% in Dextrose 5% solution was started (8.0 ml/kg/hr). Every patient had automated blood pressure, electrocardiogram, and pulse oximetry monitoring. After baseline hemodynamic data were obtained, the patient was positioned in the sitting position for spinal blockade. Patients were randomly allocated into one of two equal groups according to a list of random numbers: Group I (n = 20), received 2.0 ml of 0.6% plain ropivacaine (12 mg) and Group II (n = 20), 2.0 ml of AJAICAJAIC-Vol. (10) No. 1 Marsh 2007 Alexandria Journal of Anaesthesia and Intensive Care 0.6% hyperbaric ropivacaine (adding dextrose 50 mg/ml plain ropivacaine). Fentanyl 10 ug was added to each solution. All solutions were provided in blinded vials by the hospital pharmacy. Injections were made with 25-gauge Quincke needle at the L4-5 level over a period of 10-15 seconds, and the time of which was defined as ‘zero’. Patients immediately were put in 30º head up position; their legs were wrapped with elastic bandage and they were placed in the lithotomy position. All patient received O2 via face mask (6 l/min). The block was then evaluated by a research nurse at 5 and 10 min after local anesthetic injection. Sensory block was evaluated with the short bevel end of a 27gauge dental needle: for caudal and cephalad limits and duration of sensory block (from onset of spinal anesthesia to the regression to S2 level) were recorded. Motor block was also assessed with a modified Bromage scale(14) (mBS; 0, full movement; 1, loss of hip flexor; 2, loss of knee extension; 3, loss of planter flexion/extension), and recorded the pulse rate and mean blood pressure 2, 5, 10, 15, 20, 25, and 30 min after injection, hypotension (more than 15% decrease in mean blood pressure from baseline) was treated with IV ephedrine 2-5 mg and 5% albumin solution as required. The patient’s ability to ambulate was assessed every 30 minutes after transportation of patients to the postanesthesia care unit (PACU) until 13 unsupported ambulation has been achieved. Continued non-invasive monitoring of blood pressure, SpO2, respiratory rate, electrocardiograph and heart rate were recorded every 15 min in the first hr and then hourly until the block completely faded. Patients were kept in the hospital for 48 hr for surgical re-evaluation and recheck of his liver function. During this period patients were hemodynamically assessed every 3 hours and upon patient request. Bladder catheterization was performed when surgically indicated, but time to micturition was recorded in all other patients. Patients were telephoned 48 h and 7 days later to identify any sequlae. Statistics: Data are presented as median [range], mean (SD) or frequencies as appropriate. Block characteristics were compared using the two-tailed Mann– Whitney U-test. A P value of <0.05 was considered statistically significant. Data were analyzed using a standard computer based statistics package (Number Cruncher Statistical Systems [version 2001], Cork, Ireland). RESULTS Patients' demographic data, duration and type of surgery were listed in (Table I). The two groups were comparable with respect to age, weight, height, male/female ratio and duration of surgery. Table I: Patient characteristics and duration of surgery Group I (n=20) (Plain ropivacaine) 13/7 41.6 ± 8.1 60.7 ± 11.8 173.4±6.4 0/16/4 Group II (n=20) (Hyperbaric ropivacaine) 14/6 42.1 ±9.1 59.7 ± 11.1 171.9±7.1 0/16/4 Male/female Age (yr) Body weight (kg) Height (cm) ASA I/II/III Child-Pugh Classification A/B/C 20/0/0 20/0/0 Duration of surgery (min) 38.4±15.8 39.1±14.1 Type of surgery: Hemorrhoidectomy 16 15 Sphincterotomy 3 3 Fistula repair 1 2 Data are presented as mean ± SD. No significant difference between groups AJAICAJAIC-Vol. (10) No. 1 Marsh 2007 Alexandria Journal of Anaesthesia and Intensive Care No patient in group II required either sedative/analgesics or induction of general anesthesia. In group I, where plain ropivacaine was used, three patient required supplementation with sedative and analgesics (2.0 mg midazolam/25 µg fentanyl) to tolerate the anal dilatation (Table II). Hyperbaric ropivacaine block (group II) produced a significant rapid onset (3 min vs 9 min in plain, P<0.01) and complete regression of sensory block to S2 in significantly shorter duration (156 min vs 183 in plain P<0.05) compared to plain ropivacaine group I. The onset of motor block was slightly faster in the hyperbaric group, but the maximum degree obtained was the same in both groups. Median times to complete regression of motor block were significantly longer in the plain group (plain 158 min vs 123 min hyperbaric; P<0.05). 14 Patients mobilized sooner in the hyperbaric group (131min vs 192 min in plain P<0.01). No Transient Neurological Symptoms (TNS) or post-spinal headache has been reported in any patient of the two groups in the first 48 hr after surgery. No patient experienced respiratory hypotension or bradycardia during the intra or postoperative periods. Also, no patients in the two groups suffered urine retention and time to micturate was comparable. Three patients suffered pruritus in group I, and four patients in group II. However, pruritus was very mild and no patient asked for treatment (Table IV). There were no significant differences in the incidence of nausea and consumption of antiemetic (Table IV). Lastly, liver function tests and Child-Pugh classification showed no significant changes in both groups compared to the base-line values (Table V). Table II: Characteristics of spinal anesthesia in each group Sedative analgesics supplementation Induction of general anesthesia Onset of sensory block at T10 (min) Highest level of sensory block (range) Time to T10 sensory regression (min) Time to S2 regression (min) Time of onset of motor block (min) Duration of motor block to Bromag 1 (min) Time to ambulate (min) Group-I (n=20) 3 (15%)* 0 9.12±3.9* (P<0.01) T8 (T4-11)* P<0.05 113±23* P<0.01 183 ± 49* P<0.05 8.11±3.4 158 ± 28* P<0.05 192 ± 27* P<0.01 Group-II (n=20) 0 0 3.17±2.5 T6 (T4-10) 66±24 156 ± 32 7.71±3.3 123 ± 34 131 ± 28 Table IV: Incidence of post operative adverse effects Nausea (%) Pruritus (%) Postdural puncture headache (48 hr) : Incidence of TNS Urine retention Group-I (n=20) 2 (10%) 3 (15%) 0 0 0 Group-II (n=20) 2 (10%) 4 (20%) 0 0 0 Table V: Liver function tests and Child-Pugh classification in both groups Liver function tests Group-II (n=20) Group-II (n=20) preOp postOp preOp postOp Albumin (gm/dl) 3.9±0.6 3.8±0.7 3.9±0.6 3.9±0.7 PT (sec. prolonged) 2.9±1.3 3.0±1.2 3.0±1.1 3.0±1.2 ALT (IU, N=38) 68±14 71±15 69±16 69±15 GGT (U/L. N=11-50) 64±11 63±12 63±12 63±11 Child classification (n) A (20) A (20) A (20) A (20) preOp (preoperatively), postOp (postoperatively), PT (Prothrombin Time), ALT (Alanine Aminotranferase ), GGT (Gamma Glutamyl Transferase) AJAICAJAIC-Vol. (10) No. 1 Marsh 2007 Alexandria Journal of Anaesthesia and Intensive Care DISCUSSION Liver cirrhosis with portal hypertension, coagulopathy, altered drug pharmacokinetics and pharmacodynamics and the accelerated hypercatabolic state significantly altered the physiological response of those patients during any kind of stress whether surgical or non surgical(15). Coagulopathy, hypotension and pain are the triad of pathological events that might complicate any surgical course in those patients with an unexpected outcome ranged from postoperative bleeding, hematoma formation and infection up to encephalopathy and coma(16). This study was designed to examine the efficacy and the adverse effects of either plain or hyperbaric ropivacaine-fentanyl spinal anesthesia for anorectal surgery in cirrhotics. The present study showed that a hyperbaric solution of ropivacaine produces a more consistent block than a plain one. Addition of glucose led to a more rapid spread to a higher median level and with less variation in maximum sensory and motor block. Moreover, complete regression occurred sooner, allowing the patients to mobilize earlier. This result documented that increase the density of ropivacaine produced by addition of glucose resulted in a more even distribution of the local anesthetic, and encouraging the spread of the drug bolus ‘down’ the slopes of the lumbar curve when the patient is placed supine after injection due to the gravity effect(17). Usually, glucose-free solutions are marginally hypobaric, and have been found previously to be ‘unpredictable’, perhaps because gravity does not encourage their spread in the supine position. Spread is likely to be more dependent on other factors such as the currents produced by injection and simple diffusion. This may mean that more of the injected drug stays closer to the point of injection, making the block less useful for surgery, yet prolonging significantly sacral nerve block and so delaying recovery(18). The last explanation would answer the 15% failure rate in plain ropivacaine group, were anesthesia was not 15 sufficient in three patients and necessitated supplements of midazolam/fentanyl IV. In two previous studies of Fettes and Hocking(19,20), using 3 ml ropivacaine 5 mg/ml in either glucose 10 mg/ml or glucose 50 mg/ml, produced a block that was predictable, and adequate for lower limb surgery in all patients. Similar findings have also been obtained by others using somewhat different protocols (e.g. larger doses: 22.5 mg hyperbaric ropivacaine) for spinal anesthesia for Caesarean section(21). On the other hand, McNamee et al(9) used smaller doses of drugs, they found that, 7.5 mg of 0.5% hyperbaric ropivacaine and 5 mg of 0.5% hyperbaric levobupivacaine provide adequate spinal block for outpatient knee arthroscopy, with a faster home discharge as compared with 7.5 mg of 0.5% hyperbaric levobupivacaine. Khaw et al(22) compared 15 mg of either plain or hyperbaric ropivacaine to 10 mg of hyperbaric bupivacaine in cesarean section. The hyperbaric ropivacaine and bupivacaine preparation produced a higher, more consistent block with faster onset and recovery in all case, whereas there was a 16% failure rate with the plain solution, which is very close to our results. While variability in spread can be minimized by adding glucose, the variation in duration is very much a patient-specific factor. The average duration can be influenced by drug and dose choices, but the variability remains. This variability is even evident between studies. In the previous study, the median duration of 15 mg hyperbaric ropivacaine (with glucose 50 mg/ml) at T10 was 56 min, whereas it was 66 min in the present study although we used smaller dose (12 mg hyperbaric ropivacaine). On the contrary to our results, McDonald et al(23), used sub-clinical doses of hyperbaric ropivacaine in volunteers, concluded that it was less potent than bupivacaine and offered no advantage for use in outpatient anesthesia. However, what they found was that ropivacaine produced sensory block of similar onset and extent as bupivacaine, but that it was associated with less motor block and faster regression of both sensory and motor block, findings similar to those reported here. However these results are of great interest to liver patients as it gives a reliable précised anesthetic course. AJAICAJAIC-Vol. (10) No. 1 Marsh 2007 Alexandria Journal of Anaesthesia and Intensive Care In the present study, fentanyl in a selected dose of 10µg has been added to the anesthetic solution. Reuben et al(24) reviewed the benefits of using lipophilic opioids fentanyl as adjuncts to spinal anesthesia. They concluded that, fentanyl improved the quality of spinal anesthesia without prolongation of motor block, allow the anesthetist to use smaller doses of spinal local anesthetic, yet still provide excellent anesthesia for surgical procedures. Furthermore, fentanyl/local anesthetic combination permits more rapid motor recovery; short outpatient procedures are therefore more amenable to spinal anesthesia. Side-effect profiles of intrathecal lipophilic opioids are now well characterized and appear less troublesome than intrathecal morphine(25). Buckenmaier et al(26) found that, the use of ultra-small dose of ropivacaine 4.0 mg is similar to lidocaine 25 mg in providing acceptable surgical anesthesia for anorectal surgery in an ambulatory setting. They also proved that intrathecal fentanyl 25 µg provided analgesia longer than either small-dose local anesthetic could have achieved if used alone without affecting the motor blockade, Goel et al(27) compared different doses of fentanyl added to bupivacaine for spinal anesthesia in day case surgery reported that, the addition of increasing doses of intrathecal fentanyl (10, 20, 30, 40, and 50 µg) significantly improved the quality and duration of analgesia without significant increase in the incidence of severe The current study complications. demonstrated that adding 10 µg intrathecal fentanyl to ropivacaine (group I, II) induced sufficient anesthetic/analgesic effects without major side effects. Pilar Taurá et al(28) used small dose ketamine (20/30 mg) plus morphine (3.5-5 mg) through single shot epidural analgesia in cirrhotic patients Child-A class undergoing liver resection. Their results proved that, the introduction of epidural needle in Child’s A patients was without side effects. Secondly, postoperative analgesia provided by a single shot of epidural morphine combined with small-dose ketamine is effective and safe and represents an alternative technique in cirrhotic undergoing any type of major upper abdominal surgery. 16 Beers et al(29) reported that a low-lumbar block level (L4-5) or saddle block provided adequate anesthesia for ano-rectal surgery. However, they reported that if anal dilatation has to be done, saddle shaped anesthesia in this case is not enough and mid or low-lumber blocks are recommended. In our study, the intrathecal anesthesia was efficient in all groups except for three patients in group I who required sedative and analgesics during anal dilatation. This failure in group I might be due to the drug rather than block technique applied. Plain ropivacaine produce variable anesthesia secondary to limited caudal spread(17). Pruritus is a common complication when intrathecal opioids are used. Liu(1) found that the addition of 20 µg of fentanyl intrathecally led to pruritus in all of their patients. In the current study, pruritus was reported in 3 patients (15%) of group I patients and 4 patients (20%) in group II. Pruritus was for a short duration and of mild intensity, and needs no treatment. No incidence of Transient Neurological Symptoms (TNSs) or post-spinal headache was reported in any patient in the two groups. Yegin et al(30) reported that, the incidence of TNS among 86 TURP patients under hyperbaric ropivacaine spinal anesthesia was seldom. Lim and Yoo(31) found that, among 960 patients undergoing ambulatory surgery under either saddle shaped or low-lumber spinal anesthesia, incidence of post-spinal headache showed no difference (2.5% vs 2.3%). They found that, no cases were reported in the first postoperative day, 70% in the second day and 26% in the third day. The incidence of post-spinal headache in the present study was nil in either group, a result which was also obtained in the work carried out by Cappelleri et al(32). The present study supports the safety of practicing spinal anesthesia in cirrhotic patients in anorectal surgery. This result is supported by the work carried by Siniscalchi et al(33). They compared the intraoperative effects of combined epidural-general versus general anesthesia during major liver surgery. Group A received general anesthesia 15 minutes after placement of an epidural catheter (T9-T10). Continuous epidural infusion was initiated before AJAICAJAIC-Vol. (10) No. 1 Marsh 2007 Alexandria Journal of Anaesthesia and Intensive Care surgical incision and continued with 0.2% naropine (7 ml/h) until the end of the operation. Group B (GA) received general anesthesia with fentanyl doses according to haemodynamic parameters. Pain intensity on recovery in patients who received epidural anesthesia was lower both at rest and on movement. Only the patients in Group B required additional analgesics. No motor blockade was observed in either group. Nausea and vomiting were more frequent in Group B; hypotension was more frequent in Group A. The study confirmed the safety of low thoracic epidural anesthesia in liver surgery, and recommended its use as a fixed element of anesthesia for liver patient without fear of developing epidural haematoma or the occurrence of severe haemodynamic changes. In conclusion, the practice of spinal anesthesia in patients with liver cirrhosis of Child-A severity is a reliable anesthetic technique and no complications were reported. The hyperbaric ropivacaine produced more predictable and reliable sensory and motor block, with faster onset, than a plain solution. Moreover, the speed of recovery from both sensory and motor block is significantly better in hyperbaric ropivacaine. This clinical profile of the hyperbaric ropivacaine gives reasonable choice for cirrhotic patients in case of surgery to the ano-rectal area. 5. 6. 7. 8. 9. 10. 11. REFERENCES 1. Liu SS. Optimizing spinal anesthesia for ambulatory surgery. Reg Anesth 1997; 22: 500-10 2. De Knegt RJ, Schalm SW, Van der Rijit CC et al. Extracellular brain glutamate during acute liver failure and during acute hyperammonemia simulating acute liver failure: an experimental study based on in vivo brain dialysis. J Hepatol 1994; 20: 19-26 3. Pelton JJ, Hoffman JP, Eisenberg BL. 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