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Objective To explore the safety and feasibility of single-segment paravertebral nerve block(PVNB)in elderly patients undergoing inguinal hernioplasty.Methods A retrospective analysis was made on clinical data of 58 elderly patients who underwent open tension-free inguinal hernioplasty from January 2016 to December 2022.According to the anesthesia method,they were divided into two groups with 29 cases in each:single-segment PVNB group(P group)and single subarachnoid block group(S group).Patients in the P group were given L1 single-segment PVNB guided by ultrasound combined with peripheral nerve stimulators or simple peripheral nerve stimulators by using 0.4%ropivacaine 20 ml.Patients in the S group underwent puncture in the interspinous space between L3/4 and received 0.5%bupivacaine 10 mg.The mean arterial pressure and heart rate before anesthesia(T0),at the time of skin incision(T1),at the time of hernia sac dissection(T2),and at the time of wound closure(T3)were recorded,and the block levels,anesthetic effect,remedial rate of fentanyl,local anesthetic toxicity,peripheral nerve injury,urinary retention,delirium,and nausea and vomiting of the patients were recorded.The patient's satisfaction with anesthesia was followed up.Results All the 58 patients underwent surgery smoothly.The difference in block levels was statistically significant between the two groups of patients(Z =-4.144,P =0.000),while the differences in the remedial rate of fentanyl,anesthesia effect,and anesthesia satisfaction were not statistically significant(χ2 =0.269,P =0.604;Z =-1.430,P =0.153;Z =-1.395,P =0.163).There were no statistically significant differences in mean arterial pressure and heart rate changes between the two groups at different time points(F =0.002,P = 0.960;F =0.260,P =0.612).The rate of urinary retention in the P group was significantly lower than that in the S group(0.0%vs.24.1%,Fisher's test,P =0.010).There were no statistically significant differences in rates of dilirium and nausea and vomitting(P>0.05).All the patients did not experience local anesthetic toxicity or peripheral nerve injury during the perioperative period.Conclusion Single-segment PVNB can provide comprehensive anesthesia and analgesia for elderly patients undergoing inguinal hernioplasty,helping to maintain the stability of intraoperative hemodynamics and reducing the risk of postoperative adverse reactions.
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Background:About 52% of patients who undergo Cesarean delivery under spinal or epidural anesthesia will experience shivering, which may interfere with the monitoring of vital signs. Recent studies have shown that dexmedetomidine could potentially help to mitigate shivering associated with anesthesia. In accordance with them we decided to investigate the capability of dexmedetomidine, an alpha 2-adrenergic agonist, in reducing the duration of shivering associated with spinal anesthesia during Cesarean delivery. Material And Methods:Forty parturient going through Cesarean delivery under spinal anesthesia and experiencing shivering were included in this randomized, double-blind, prospective trial. After delivery, the intervention group (n = 20) was administered a single intravenous bolus of dexmedetomidine (20 microgram) while the control group (n =20) was given normal saline. Randomization and allocation were based on a computer-generated list. The primary outcome parameter was the time required for an observable reduction in shivering after the intervention. Result:Eighty patients were recruited, 40 of whom presented with shivering and underwent randomization. Our study recorded that dexmedetomidine alleviated the mean duration of shivering after a single intravenous bolus to 2.2 (2.07) min after dexmedetomidine from 18.9 (12.72) min after saline (95% confidence interval [CI],). The effect of dexmedetomidine was sustained 15 min after the bolus was administered, and shivering had completely stopped in 90% of the patients in the intervention group vs. 22.6% in the control group. No adverse effects were recorded. Conclusion:Our study found that a single intravenous bolus of dexmedetomidine reduced the duration of shivering for up to 15 min during Cesarean delivery under spinal anesthesia when compared against a placebo.
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Objective:To explore the clinical value of ultrasonic inferior vena cava parameters in predicting supine hypotension syndrome after subarachnoid block.Methods:80 cases of cesarean section under subarachnoid block in singleton pregnancy treated in Beijing Maternity Hospital from August 2019 to March 2020 were selected retrospectively. According to the occurrence of supine hypotension syndrome after anesthesia, they were divided into two groups (group A had supine hypotension syndrome and group B did not), with 40 cases in each group. The changes of related parameters of inferior vena cava in supine position and left 30 ° lying position were compared between the two groups. The correlation between the maximum end expiratory diameter (IVCe), the minimum end inspiratory diameter (IVCi) and the collapse index (IVC-CI) of inferior vena cava and the changes of systolic blood pressure in supine hypotension syndrome were analyzed, and the value of IVCe, IVCi and IVC-CI in predicting supine hypotension syndrome were compared.Results:Under the condition of supine position and left 30 ° lying position, the levels of IVCe and IVCi in group A were significantly lower than those in group B ( P<0.05), and the levels of IVC-CI were higher than those in group B ( P<0.05). Spearman analysis showed that the levels of IVCe and IVCi were positively correlated with the changes of systolic blood pressure in the occurrence of supine hypotension syndrome ( P<0.05), and the levels of IVC-CI were negatively correlated with the changes of systolic blood pressure in the occurrence of supine hypotension syndrome ( P<0.05). IVC-CI had the highest yoden index and the highest sensitivity in predicting the occurrence of supine hypotension syndrome, and IVCe had the highest specificity in predicting the occurrence of supine hypotension syndrome. Conclusions:Cava collapse index has high sensitivity to predict supine hypotension syndrome, while the maximum end-expiratory diameter of inferior vena cava has high specificity to predict supine hypotension syndrome.
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The present study aimed at clinical evalution of dexmedetomidine 10 microgm, as an adjuvant to heavy bupivacaine 0.5% (4 ml) in subarachnoid block in patients scheduled for lower abdominal surgeries. Total no. of patients included in the study are 66 who are admitted in orthopaedic ward for lower limb surgeries, who are of ASAgrade I & II and age group between 18-60yrs. All the routine investigations of the patients were done and after complete PAC and preoperative preparations, patients were taken into O.T, all the standard monitoring applied and for subarachnoid block hyperbaric Bupivacaine 0.5% is a dose of 4ml (20mg) combined with or without Dexmedetomidine was administrated according to the assigned study group: 1.Group A- Inj. Bupivacaine- 20mg alone- control group 2.Group B- Inj. Bupivacaine- 20mg with Dexmedetomidine 10mcg-study group Data on onset & offset of sensory & motor block, degree of muscle relaxation, postoperative pain free period were recorded. Dermatome level of block, vitals & drug related complications were also noted. On the basis of observations, following conclusions are drawn: Rapid onset & increased duration of sensory block was seen in Grp B, Onset of motor block & post operative pain free period was prolonged in Grp. B. Sedation score was from 0-2 in study group.Other complications in study group were not significant.
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BACKGROUND: Hypotension after spinal anaesthesia for Caesarean section still remains a common complication. Various methods have been recommended for prevention and treatment of this problem. However, despite crystalloid or colloid preloading, hypotension remains a common problem. Vasopressors are required to treat the spinal induced hypotension among most of these patients. Studies involving bolus phenylephrine are in plenty but studies pertaining to prophylactic phenylephrine infusion are sparse.
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Background: Shivering is a frequent complication of regional anaesthesia. This study aimed to compare efficacy of Dexmedetomidine and Tramadol in treating post subarachnoid block shivering and their side effects. Methods: Prospective, experimental, randomized, comparative study of 60 patients of ASA grade–l & II of either gender, aged 18 to 60 years scheduled for elective surgeries, under subarachnoid block were allocated to two groups: Group T (n=30) received intravenous (IV) Tramadol 0.5 mg/kg and Group D (n=30) received IV Dexmedetomidine 0.5 µg/kg. Grade of shivering, time interval from treatment to cessation of shivering, hemodynamics and side effects were observed. Results: Recovery time from shivering was 40.34(± 6.20) sec in Dexmedetomidine whereas 210.3(±26.97) sec in Tramadol group. Side effects nausea and vomiting in Tramadol group whereas sedation and adycardia in Dexmedetomidine group were significant. Conclusion: Dexmedetomidine offers better thermodynamics than Tramadol.
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Objective To investigate the advantages and disadvantages of oxycodone combined subarachnoid block and intravenous-inhalational anesthesia in elderly patients with femoral trochanter fracturethe surgery.Methods Thirty-four patients undergoing elective surgery with closed reduction and Proximal femoral nail anti-rotation (PFNA) fixation,13 males and 21 females,aged 76-92 years,ASA physical status Ⅱ or Ⅲ,were equally randomized into two groups (n =17 each):group O and group C.Patients in group O received oxycodone combined subarachnoid block.Patients in group C received intravenous-inhalational anesthesia.Patients in group C were not premeditated beforel entering the operation room.After entering the rooms group O was given oxycodone 3-5 mg i.v first,then given ropivacaine in subarachnoid space.All patients were induced with intravenous of sulfentanil 0.2-0.3μg/kg,cisatracurium 0.15 mg/kg,etomidate 0.1-0.2 mg/kg slowly.Anesthesia was maintained by intravenous propofol 3-5 mg· kg-1 · h-1,remifentanyl 0.1-0.3 μg · kg-1 · h-1,sevofrane 0.55％-2％ infusion,intravenous bolus cisatracurium 0.05-0.10 mg/kg.The anesthesia related complications and length of hospital stay were recorded.Results Postoperative nausea and vomiting (PONV) respiratory depression of group O was significantly lower than that of group C [2(11.8％) cases vs 9 (52.9％) cases,P＜0.05],length of hospital stay of group O was significantly shorter than that of group C [(10.4±1.6) d vs (15.8±2.0) d,P＜0.05].Conclusion In the elderly patients with femoral intertrochanteric fracture closed reduction and PFNA internal fixation,oxycodone combined subarachnoid block may improve patients' recovery.
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Objective To compare the effects of isoflurane and pentobarbital on the establishment of subarachnoid block model in rats.Methods 60 SD rats aged 4 months were randomly divided into Group A (n =30) and Group B (n=30).Rats in Group A received intraperitoncal injection of 10 g/L pentobarbital sodium solution 30 mg/kg and 1/4 of the initial dosage was added according to the operation effect.The induction and maintenance of anesthesia were achieved by isoflurane inhalation in Group B during operation.We recorded the time of anesthesia induction,quality of anesthesia,time of anesthesia,time of operation,and recovery time.The heart rate,respiration frequency,temperature,and saturation of blood oxygen were recorded during operation.We compared death from anesthesia and success of modeling in the two groups.Results There was no significant difference between the groups with regard to age,weight,body temperature or saturation of blood oxygen (P＞ 0.05).Compared to Group B,heart rate decreased 1-60 minutes after anesthesia and respiration frequency decreased 5 minutes after anesthesia in Group A (P＜0.05).The time of anesthesia induction,time of anesthesia,time of operation,and recovery time were shorter in Group B (P＜0.05).The quality of anesthesia was better in Group B (P＜0.05).The success rate of modeling was higher but mortality rate of anesthesia was lower in Group B than in Group A (P＜0.05).Conclusion Compared with intraperitoneal injection of pentobarbital sodium,isoflurane inhalation can provide a better anesthetic effect during the operation to establish a rat model of subarachnoid block.
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Background: Hydrocele surgery is a short surgical procedure requiring an anaesthetic technique that allows good surgical anaesthesia, short recovery time and minimal side effects. This study was designed to compare the traditionally used technique of local infiltration block and subarachnoid block using 1% lidocaine with 25mcg of fentanyl in patients undergoing hydrocele surgery. Methods: Sixty ASA grade I and II patients of 18-60 years of age, scheduled for hydrocele surgery were randomly assigned to two groups of 30 patients each. Group C patients received local infiltration using 1% lidocaine (maximum upto 5mg /kg) while Group I patients received intrathecal injection of 1% lidocaine with 25 mcg of fentanyl (1.5 ml of 2% lidocaine + 1 ml of normal saline + 0.5 ml fentanyl). The subjects were assessed in terms of physiological variables, the quality of analgesia, and incidence of side effects as compared to local infiltration technique. Results: Patients in group C required significantly more number of fentanyl boluses for pain as compared to patients in group I. The most common problem encountered in any group was backache with an incidence of 16.6% in group I and 6.6% in group C. Pruritus was reported to be 13.3% in group I but was absent in group C (P<0.05). However, it was mild and did not require any medication. 23 patients in group I regarded their experience of the perioperative period as excellent as compared to only 5 patients in group C. Time to void and to meet discharge criteria was comparable in both the groups. Conclusion: We conclude that the use of smaller dose lidocaine-fentanyl combination in spinal anaesthesia provides potent and excellent quality of analgesia with limited side effects without prolonging recovery as compared to 1% lidocaine infiltration in patients of hydrocele surgery.
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Background: There are many accepted anesthesia techniques for elective foot surgery ranging from general anesthesia to regional anesthesia, regional anesthesia being the preferred method. Regional anesthesia techniques employed for foot surgery includes subarachnoid block, epidural anesthesia and ankle block. Objective: The present study is aimed at providing comparative analysis of ankle block with unilateral subarachnoid block for elective foot surgeries in terms of hemodynamic safety profile and post operative analgesia. Material and Methods: Study includes prospective analysis of 80 ASA II and III patients who underwent elective foot surgery. Patients were randomly divided into two groups of 40 each, Ankle block group (AB) and Unilateral subarachnoid group (US). The parameters recorded for study includes systolic blood pressure, diastolic blood pressure, heart rate, visual analogue scale for pain severity, time of first analgesic need and the complications. Results: There were minimal blood pressure changes and heart rate variability in AB group as compared to US group when compared with basal values (p<0.05). The time for first analgesic requirement is prolonged in AB group as compared to US group. The visual analogue scale score was assessed at 2nd ,4th and 6th hours for group AB were lowered as compared to group US (p <0.05).
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Background: We studied the sedative and analgesic effect of intravenous dexmedetomidine in patients posted for meshplasty for the repair of inguinal hernia under subarachnoid block with 0.5% hyperbaric bupivacaine. Methods: Fifty patients of the American Society of Anaesthesiologists (ASA) physical status I or II of either sex (20 – 50 years) presenting for meshplasty for inguinal hernia were included in the prospective double-blind randomized study. All patients received 2.5 ml of 0.5% hyperbaric bupivacaine intrathecally. Patients were randomly allocated on the basis of a sealed envelope technique to receive one of the following after subarachnoid block: Group D (n=25) - Loading dose of 1 μg kg-1 dexmedetomidine over 10 minutes started 20 minutes after spinal block + maintenance dose of 0.4 μg kg-1 hr-1 dexmedetomidine till the end of surgery; Group P (n=25) - same calculated volume of normal saline as a loading dose over 10 minutes + maintenance till end of surgery. Data regarding the VAS score, duration of analgesia were recorded. Results: Patients in group D had a significantly higher sedation score than those in group P (p< 0.001). Dexmedetomidine significantly reduced the requirement of diclofenac injection for pain relief in 24 hours postoperative period (p< 0.001). Conclusion: Intravenous dexmedetomidine resulted in significant prolongation of time to VAS ≥ 4, reduced postoperative analgesic requirement and produced good sedation levels without significant haemodynamic compromise.
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OBJECTIVE:To explore the effect of subarachnoid block anesthesia in endoulogy minimally invasive surgery of el-derly patients. METHODS:198 elderly patients underwent endoulogy minimally invasive surgery were randomly divided into obser-vation group (100 cases) and control group (98 cases). Observation group received subarachnoid block anesthesia,and control group received epidural anesthesia. The anesthesia onset time,anesthesia dose,surgery time,complete block time,satisfaction de-gree of anesthesia effect,the occurrence of ADR were compared between 2 groups. RESULTS:Anesthesia onset time and complete block time of observation group were (1.5 ± 0.6) min and (7.9 ± 3.9)min,which were significantly shorter than those of control group (4.5 ± 1.2) and (17.5 ± 4.3) min,with statistical significance (P0.05). CONCLUSIONS:Subarachnoid block anesthesia consumes small dose,acts rapidly and shows significant anesthesia effect,it is used for endoulogy minimally invasive surgery of elderly patients.
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Spinal anesthesia with advantages of easy operation, fast effect and small maternal and neonatal effects has always been the preferred anes?thetic technique for cesarean section in China. However, maternal hypotension induced by spinal anesthesia remain a large challenge for anaesthetist. Perioperative fluid management plays important roles in maintaining maternal and fetal hemodynamics. This review mainly analyzes pathophysiological mechanism of maternal hypotension induced by spinal anesthesia,introduces different fluid?management strategy and functions on prevention of maternal hypotension.
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Background: Subarachnoid block is a safe and effective alternative to general anaesthesia when surgical site is located on the lower extremities, perineum or lower body wall. Spinal anaesthesia produces intense sensory and motor blockade as well as sympathetic blockade. Intrathecal α-2-agonists are used as adjuvant drugs to local anaesthetics successfully over the last decade .They potentiate the effect of local anaesthetic and decrease the required doses. Clonidine is a partial α-2-adrenorecptor agonist used intrathecally, with a well- established record of efficacy and safety. Its addition to local anaesthetics prolongs the duration of both motor and sensory spinal blockade. Dexmedetomidine is an α-2-adrenorecptor agonist. It has α-2/α1 selectivity ratio which is eight times higher than that of Clonidine. With this background, this study was conducted to compare the effects of intrathecal Ropivacaine plus Dexmedetomidine versus Ropivacaine plus Clonidine during procedures. Methods: The present prospective study was carried out in the Department of Anaesthesiology, M.G.M. Medical College and M.Y. Hospital, Indore (M.P.), India. Study period was from June 2011 to July 2012. Patient were randomly allocated to one of the following three group in a double blinded fashion based on computer generated code: Ropivacaine (R), Ropivacaine + Dexmedetomidine (D); Ropivacaine + Clonidine (C). Nominal categorical data between study groups were compared using the Chi – squared test or Fisher’s exact test as appropriate. p<0.05 was considered to be significant. Results: In all age groups patients were equally distributed in three Groups. Mean time taken for the onset of sensory and motor block was quite low in group D patients. Thereby showing statistically highly significant difference in onset of sensory and motor blocks (P<0.001). Whereas mean duration of sensory and motor block was also quite prolonged in group D patients. (p<0.001) There is significant difference between all the three groups. Conclusion: In conclusion our study shows that intrathecal Dexmedetomidine or Clonidine added with isobaric Ropivacaine produces rapid and prolonged sensory and motor block as compared to plain Ropivacaine.
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Objective To compare the anesthesia effect and adverse effect of subarachnoid block anesthesia with different doses of sufentanil combined with bupivacaine 7.5 mg in aged patients,and explore the suitable dosage of sufentanil.Methods Eighty aged patients with ASA grade Ⅰ-Ⅲ undergoing elective lower limb surgery were divided into 4 groups by random digits table and each group was in 20 cases:group Ⅰ received bupivacaine 7.5 mg,group Ⅱ received bupivacaine 7.5 mg+sufentanil 2.5 μg,group Ⅲ received bupivacaine 7.5 mg+ sufentanil 5.0 μg,group Ⅳ received bupivacaine 7.5 mg+ sufentanil 7.5 μg.The vital signs,degree of motor and sensory nerve blockade and adverse effect were observed.Results Compared with base blood pressure,systolic blood pressure(SBP)and diastolic blood pressure(DBP)in group Ⅰ was significantly decreased after intrathecal injecton 15,30,45,60 minutes(P ＜0.05).There were no significant differences in the degree of motor nerve blockade in four groups(P ＞ 0.05).The time of sensory nerve blockade in group Ⅰ[(194 ± 58)min]was significantly shorter than that in group Ⅱ,Ⅲ,Ⅳ[(255 ±44),(242 ±58),(308 ± 123)min](P ＜0.05).The time of sensory nerve blockade in group Ⅳ was significantly longer compared with group Ⅱ and Ⅲ(P ＜ 0.05).The number of pruritus in group Ⅳ(10 cases)was significantly more than that in group Ⅰ and Ⅱ(0,4 cases)(P＜0.05).Conclusion Subarachnoid block anesthesia with sufentanil 2.5 or 5.0 μg combined with bupivacaine 7.5 mg in aged patients is safe and effective.
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Objective To explore the clinical efficacy and safety of low dose fentanyl combined to ropivacaine in subarachnoid block for cesarean section.Methods Eighty patients with ASA physical status Ⅰ and Ⅱscheduled to undergo cesarean section for delivery were randomly allocated to receiving spinally mixture none fentanyl ( group R),5 μg fentanyl ( group F5 ), 10 μg fentanyl ( group F10 ), and 15μg fentanyl ( group F15 ), combined with 1%ropivacaine 1 ml and 10% glucose 1 ml respectively,after combined spinal-epidural anesthesia puncture was applied at the L2～3 interspace.Heart rate, blood pressure, the onset and recovery time of the sensory and motor block,time to the highest level and the highest level of sensory block, time to the maximal extent and the maximal extent of the motor block were recorded at regular intervals.The adverse effects were sought during and after surgery.Neonatal outcome was assessed using Apgar score.Results The recovery of sensory block was prolonged significantly in group F10 and group F15 than in group R and group F5.Conclusion Ropivacaine with 10μg fentanyl is safe and effective in subarachnoid block for cesarean section.
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Objective To observe the anaesthetic effect of sulfentanil combined with bupivacaine for subarachnoid block on cesarean section patients and the influence on the patient and fetus.Methods Eighty patients who were scheduled for elective cesarean section under subarachnoid block,were distributed into two groups:bupivacaine with no sulfenlanil(group B)and bupivacaine with sulfentanil(group BS).Detected SBP,DBP,MAP,HR,SpO2 before and after anesthesia.The time of drug onset,motor recovery and pain recovery were recorded,the effect of muscle relaxation was evaluated,and the drag reaction,neonatal Apgar score and anesthesia complication were recorded.Results There was no significant difference in the time of drug onset and motor recovery,muscle relaxation,neonatal Apgar score between the two groups.MAP was lower after 3-10 min of anesthesia than before anesthesia,but there was no significant difference after 30-120 min of anesthesia in the two groups.The rate of drag reaction was 27.5% in group B,but no case in group BS.The time of pain recovery was longer in group BS than that in group B(P＜0.01).The rate of temporary itch of skin after operation was 17.5% in group BS.Conclusion The addition of sulfentanil to hyperbaric bupivacaine provides adequate anesthesia for cesarean section and good postoperative analgesia.
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Objective:To evaluate the clinical safety and effectiveness of heavy specific gravity levobupivacaine in spinal block.Method:30 selective general surgical patients of ASAⅠ～Ⅱin obstetrics and gynecology were randomly di- vided into levobupivacaine group(L group)and bupivacaine group(B group).After opening the venous channel and transfusing equilibrium liquid 30 mins,the T 4-5 space was selected as the puncture site for the epidural puncture.The 2 medicaments were injected in the rate of 0.1 ml/s respectively.Then the anesthetizing onset time,maintenance time,time of motion blockade and restoration,effect of anesthesia,variations of blood pressure and heart rate and adverse drug reac- tion were observed.Result:The onset time was 82.61?22.10 s in L group and 59.30?21.50s in B group,respectively. The variations of SBP,DBP and HR in L group were less than those in B group.There was no significant difference in the 2 groups in maintenance time,time of motion blockade and restoration and effect of anesthesia.Conclusion:Compared with bupivacaine,heavy specific gravity levobupivacaine can make the same anesthesia effect with a steadier blood circulation. The specific gravity levobupivacaine is a safe and feasible drug for spinal anesthesia.
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We report a case of in which the separation of a spinal needle shaft from a hub during subarachnoid block required surgical removal of the retained shaft. A 26-year-old male was scheduled for a transurethral resection of a bladder tumor under spinal anesthesia. A 25-gauge Quincke needle was selected The needle was advanced to the junction of the hub and the L3-4 interspace through a midline approach, but the subarachnoid space was not identified When the needle was withdrawn to change of direction of needle tip, the needle shaft separated from the hub. The separated needle shaft was palpable under the patient's skin, but it's removal using a Kelly through a small incision was impossible. Under the radiographic guidance, the needle was removed after several attempts. We emphasize importance of checking epuipment prior to a subarachnoid block and the use of a careful procedure to reduce complications associated with a faulty spinal needle.
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Adulto , Humanos , Masculino , Anestesia Raquidea , Agujas , Piel , Espacio Subaracnoideo , Neoplasias de la Vejiga UrinariaRESUMEN
AIM: To observe dose-effect relationship of spinal anesthesia with 0.75% ropivacaine in caesarean section.METHODS: According to the dosage of 0.75% ropivacaine,120 full-term and single-birth puerperants were randomly divided into four groups of 30 people each.The dosage of group Ⅰ,Ⅱ,Ⅲ and Ⅳ were 1.5,1.8,2.1 and 2.4 mL respectively.The sensory and motor block of each group within 30 minutes after the injection were observed,and the hemodynamic changes and adverse effects were recorded.RESULTS:(1) Within 30 minutes after the injection,the intermediate zone of pain disappeared highest block level of group I-IV were T10,T8,T6 and T5 respectively.(2) During the period of the first 30 minutes,there were 3 cases in group Ⅲ(10%) and 8 cases in group Ⅳ(27%) appeared chest distress and dyspnea,and the blood pressure of 5 cases in group Ⅲ(17%) and 12 cases in group Ⅳ(40%) dropped to 90 mm Hg(1 mm Hg=0.133 kPa).There were significant difference compared with group IV(P0.05),there were significant difference between group IV and other groups(P