Spinal anaesthesia in 50 patients with previous lumbar spinal surgery

In anaesthesia textbooks, spinal anaesthesia is described as relatively contraindicated in patients with a history of lumbar spinal surgery. In order to assess the feasibility of spinal anaesthesia in these patients, we performed 56 spinal anaesthetics in 50 consecutive patients with previous lumbar spinal surgery. Our success rate of spinal anaesthesia was 100 %. Side effects were only minor and had a low incidence. We conclude that spinal anaesthesia is a viable technique in these patients.     

Continuous spinal anaesthesia: what's new and what's not

Continuous spinal anaesthesia combines the advantages of single-dose spinal anaesthesia, rapid onset and a high degree of success, with those of a continuous technique. The introduction of micro-catheters invigorated interest in the technique and allowed its expansion to additional populations and surgical procedures. However, multiple cases of cauda equina syndrome associated with micro-catheters and (primarily) hyperbaric lidocaine solution led to withdrawal of micro-catheters from the US market, casting doubt over the safety of continuous spinal anaesthesia as a whole. A decade after these events it is possible to look back at the experience with continuous spinal anaesthesia for operative anaesthesia and postoperative analgesia and to compare it with the available alternatives. From this perspective, continuous spinal anaesthesia remains a useful and safe technique. Future research should focus on the comparison of continuous spinal anaesthesia with the combined spinal/epidural technique and the use of newer spinal agents.     

Analyse des échecs de la rachianesthésie en fonction de l''évolution de la pratique d''un hôpital universitaire

This study is a retrospective analysis of 303 consecutive spinal anaesthesia performed in orthopaedic patients of a University Hospital between January and December 1990. Failure of spinal anaesthesia was defined as the requirement for general anaesthesia to perform surgery. The parameters studied as possible risk factors of failure were patients demographics, local anaesthetic agents and solutions and techniques of spinal anaesthesia (single injection versus continuous spinal anaesthesia). Failures were related to inadequate or incomplete extension of sensory blockade or to difficulties to perform spinal injection. Continuous spinal anaesthesia was performed in 209 patients mostly with 0.5% isobaric bupivacaine, while 94 patients received a single injection of either hyperbaric 0.5% tetracaine with adrenaline or 0.5% bupivacaine or 5% lidocaine. Failures occurred in 6.3% of the cases but were significantly less frequent with continuous spinal anaesthesia (4.8%) than with the conventional technique (9.6%). The incidence of failure was higher with hyperbaric tetracaine (11.1%) confirming its poor reliability. Inadequate extension of the anaesthetic block was the main cause of failure whatever the spinal anaesthetic technique. These results point out the reliability of continuous spinal anaesthesia but problems may occasionally occur due to spinal catheter misplacement.     

Analgesia produced by epidural diamorphine is better following caesarean section under spinal anaesthesia than under epidural anaesthesia

In a randomized double-blind study, the efficacy, duration of action and side-effects of epidural diamorphine 2.5 mg in 10 ml normal saline were compared following elective caesarean section under either spinal anaesthesia (using a combined spinal epidural technique, n = 32) or conventional epidural anaesthesia (n = 26). Median visual analogue pain scores were consistently lower in patients who had received spinal anaesthesia and this reached significance at 24 h (P = 0.02). If additional i.m. morphine was required, the mean (SD) time to its administration was significantly greater following spinal anaesthesia (12.6 h (5.9)) than epidural anaesthesia (6.6 h (3.1), P = 0.01). The incidence of side-effects was similar in the two groups. The improved analgesia following spinal anaesthesia is another advantage of the combined spinal epidural technique over conventional epidural anaesthesia for elective caesarean section.     

Spinal anaesthesia for obstetrics

For a long time, epidural anaesthesia has been considered the method of choice for Caesarean delivery. The increased incidence of hypotension by the rapid onset of sympathetic blockade under spinal anaesthesia has been associated with a decline in uteroplacental blood flow and significant fetal acidosis, which may compromise neonatal well-being. Nevertheless, a decrease in fetal pH has not been shown to reduce neonatal Apgar or neurobehavioural assessment scores. Maternal blood pressure can be preserved with little side effects with low doses of vasopressors. On the other hand, spinal anaesthesia conveys significant advantages over epidural anaesthesia such as the simplicity of its use and the speed of onset, which allows neuraxial anaesthesia in urgent Caesarean sections and thus reduces the necessity for general anaesthesia. The small doses of local anaesthetics required to perform spinal anaesthesia reduce the risks of systemic toxicity to zero. Spinal anaesthesia is now considered the method of choice for urgent Caesarean section. The use of intrathecal opioids has profoundly changed the quality of spinal anaesthesia, with improved analgesia, a reduction in local anaesthetic requirements and shorter duration of motor blockade. Preliminary studies indicate that spinal anaesthesia may be safely performed in patients with severe pre-eclampsia, in whom spinal anaesthesia was previously considered contraindicated.     

Spinal anaesthesia in infants and children

Every anaesthetist who deals with paediatric patients should have the expertise to perform spinal anaesthesia. Often, children undergoing surgery in the lower part of the body have contraindications for general anaesthesia; in these children spinal anaesthesia is a convenient option.The aim of anaesthesia is to provide good operating conditions for the surgeon while avoiding any harmful psychological sequelae for the child. In addition, the anaesthetist's goal is to lessen the physiological stress response to surgery and to prevent post-operative morbidity. In children, spinal anaesthesia produces a dense intra-operative analgesia and, when combined with general anaesthesia, it reduces the requirements for anaesthetic agents and opioids intra-operatively. Spinal anaesthesia allows a fast return to a bright and alert status, and a rapid return of normal appetite. Following spinal anaesthesia, analgesia continues into the early post-operative period, and nausea and vomiting are uncommon. Consequently, ambulation and discharge are not delayed.Some children develop complications following spinal anaesthesia—for example, a post-lumbar puncture headache and transient neurological symptoms. In young children these symptoms may be difficult to perceive if parents are not informed. When long-lasting, these symptoms may surpass the benefits of spinal anaesthesia and should therefore be identified and treated appropriately.     

The effectiveness and safety of spinal anaesthesia in the pyloromyotomy procedure

BACKGROUND: Hypertrophic pyloric stenosis is a relatively common disorder of the gastrointestinal tract in infancy, causing projectile vomiting and metabolic abnormalities. Surgical management in the form of pyloromyotomy under general anaesthesia has been reported as safe for relieving the obstructed bowel. A number of studies have demonstrated the advantages of spinal anaesthesia over general anaesthesia in high risk infants undergoing minor infraumbilical surgery. The purpose of this study was to evaluate spinal anaesthesia as an alternative option to general anaesthesia in infants undergoing pyloromyotomy. METHODS: Twenty-five infants undergoing pyloromyotomy under spinal anaesthesia were studied. Haemodynamic and respiratory parameters were noted before performing the spinal block, 5 min after the spinal block, and every 10 min after performing the spinal block; for a total period of 30 min. The spinal block was performed using spinal isobaric bupivacaine 0.5%, 0.8 mg.kg-1. Blood pressure, heart rate, respiratory rate and oxygen saturation values were recorded. RESULTS: The sensory levels achieved ranged between T3-T5 thoracic segments within 6-8 min and were sufficient to perform surgery in 23 cases. There were no statistically significant differences in the oxygen saturation, systolic blood pressure and respiratory rate compared with before the spinal block and after 5, 10, 20 and 30 min. CONCLUSIONS: This study proposes that spinal anaesthesia is an alternative option to general anaesthesia in infants undergoing pyloromyotomy, and should be considered in infants undergoing pyloromyotomy.     

Subarachnoid haematoma after spinal anaesthesia mimicking transient radicular irritation: a case report and review

I report a patient with a spinal subarachnoid haematoma after difficult spinal anaesthesia who presented with symptoms of radicular irritation, and who recovered with conservative management. Subarachnoid haematoma is rare after spinal anaesthesia; a literature review found nine cases. In the majority of these cases, spinal anaesthesia had been difficult and unsuccessful. Other risk factors included antiplatelet and anticoagulant therapy, and direct spinal cord trauma. All the previous cases required decompressive laminectomy.     

Differential sensory block: spinalvs epidural with lidocaine

PURPOSE: In this study we sought to determine if and when a difference exists with regards to differential sensory blockade between spinal and epidural anaesthesia using lidocaine. METHODS: Ten healthy volunteers were randomly assigned to receive both spinal and epidural anaesthesia. Non-epinephrine containing solutions of lidocaine, 100 mg lidocaine 5% with 7.5% dextrose (spinal) and 600 mg lidocaine 2% (epidural), were used to establish sensory blockade. At five minute intervals, for a total of 65 min, the following sensory modalities were tested: anaesthesia (complete loss of sensation to pinprick), analgesia (loss of an equally sharp sensation to pinprick compared with that at an unblocked dermatome), cold sensation (complete loss of cold temperature discrimination). RESULTS: At all times, except at time = 0 during spinal anaesthesia, the levels of analgesia and cold sensation were more cephalad than the level of anaesthesia for both spinal and epidural anaesthesia. Multiple comparison testing among the three dermatomal response levels showed that, during epidural anaesthesia, the level of analgesia was more cephalad than the level of cold sensation at the following times: 25 min, 30 min, and from 40 to 60 min. In contrast, the level of analgesia was not different from the level of cold sensation during spinal anaesthesia. CONCLUSIONS: Spinal and epidural anaesthesia with lidocaine produce a similar degree of differential sensory blockade. Epidural anaesthesia produces a detectable difference between the level of analgesia and cold sensation at various times, whereas spinal anaesthesia did not reliably do so in this study.     

Spinal anaesthesia for outpatient surgery

Spinal anaesthesia in the outpatient is characterized by rapid onset and offset, easy administration, minimal expense, and minimal side effects or complications. Spinal anaesthesia offers advantages for outpatient lower extremity, perineal, and many abdominal and gynaecological procedures. Development of small-gauge, pencil-point needles are responsible for the success of outpatient spinal anaesthesia with acceptable rates (0-2%) of postdural puncture headache (PDPH). Compared with peripheral nerve blocks, spinal anaesthesia has a more predictable offset. There are many possible choices of local anaesthetics for outpatient spinal anaesthesia. These include lidocaine, prilocaine, mepivacaine and small doses of bupivacaine. Meperidine has local anaesthetic properties in addition to its opiate properties. It has been used as the sole intrathecal agent for spinal anaesthesia but has no real advantages over lidocaine. Mepivacaine and lidocaine have each been associated with transient neurological symptoms (TNS) following intrathecal administration. This has stimulated development of alternative agents, including combinations of local anaesthetics and opioids. Lidocaine remains the most useful agent for outpatient spinal anaesthesia. For longer procedures, mepivacaine is an excellent spinal anaesthetic agent. Attention to technique, reduction of dose and addition of fentanyl to lidocaine result in effective spinal anaesthesia with rapid recovery and a low incidence of significant side effects or complications.     

Spinal anaesthesia for day case surgery.

Postoperative morbidity in fifty day care patients undergoing spinal anaesthesia was evaluated by means of a postoperative questionnaire. Despite the use of a 26G spinal needle in all patients, there was an overall incidence of spinal headache of 18%, which rose to 39% when considering patients under 40 years of age. Several spinal headaches of three to five days' duration were reported. Patients receiving spinal anaesthesia were compared with a smaller group of patients receiving general anaesthesia for similar procedures, and this group showed no evidence of post-operative morbidity after 48 h. In agreement with a previous study, it is concluded that spinal anaesthesia is not a suitable technique for the young day care patient.     

Pediatric surgery. A comparison of spinal anesthesia and general anesthesia]

Forty patients aged 2 to 5 years who were admitted for paediatric operations were randomly assigned to have either spinal or general anaesthesia. Spinal anaesthesia was achieved with isobaric bupivacaine 0.5% at a dose of 0.5 mg/kg. General anaesthesia was induced with thiopentone 2-5 mg/kg and continued with low-dose fentanyl (1-2 micrograms/kg, oxygen/nitrous oxide/isoflurane (30/70/0.1-0.5%), vecuronium normoventilating the patients. The time spent in the operation room was shorter in the spinal anaesthesia group because the children were awake and could immediately be transferred. The haemodynamic pattern and respiratory function were stable during spinal anaesthesia. After general anaesthesia, respiratory function deteriorated as indicated by arterial desaturation (< 90%), which was detected in 11 of the 20 patients after general anaesthesia. Vomiting (2), sore throat (4) and micturition difficulties (2) were the adverse events associated with general anaesthesia. Three patients were restless after spinal anaesthesia. It can be concluded that spinal anaesthesia is a suitable anaesthetic technique for paediatric surgery.     

Use of 29–gauge spinal needles and a fixation device with combined spinal epidural technique

One hundred patients between 15–46 years, undergoing elective surgery, were given spinal anaesthesia using 29–gauge spinal needles introduced through a Tuohy needle with a fixation device. Successful spinal anaesthesia was achieved in 98%. A success rate of 100% was achieved when a combined spinal epidural technique was used. Ninety–eight percent of the patients would prefer the same anaesthesia procedure for similar kind of surgery in the future.     

Abcès péridural compliquant une rachianesthésie chez un patient diabétique

Infectious complications of spinal or epidural anaesthesia are rare, particularly after spinal anaesthesia. Most of them consist of a meningitis. We report a case of epidural abscess due to s following spinal ana following spinal anaesthesia in a 62-year-old diabetic patient, diagnosed 45 days afterthe puncture with bacterial samples and magnetic resonance imaging. The pejorative neurological outcome required a laminectomy in spite of an efficient anti-staphylococcal treatment.     

A survey of anaesthetic techniques used for caesarean section in the UK in 1997

A prospective survey of anaesthesia for caesarean section was performed for the year 1 January to 31 December, 1997. Two hundred and fifty maternity hospitals were sent questionnaires from which 129 responses were obtained. The data provided information on anaesthesia for 60 455 caesarean sections. Overall 78% of sections were performed with regional anaesthesia: 47% single shot spinal; 22% epidural; 9% combined spinal epidural (CSE); 22% general anaesthesia. For elective caesarean sections (39% of all sections) regional anaesthesia was used for 87% of cases: 68% single shot spinal; 3% epidural; 15% CSE; 13% general anaesthesia. For emergency procedures regional anaesthesia was used for 72% of cases: 34% single shot spinal; 34% epidural; 4% CSE; 28% general anaesthesia. There was a wide range of regional anaesthesia use among the units, varying from an overall rate of 95% at one extreme to 41% at the other. Similarly, there was a wide range of conversion of regional anaesthesia to general anaesthesia, varying from 0% to 88%. Overall, 10.6% of the general anaesthetics were the result of regional to general anaesthesia conversion.     

SPINAL ANAESTHESIA IN YOUNG PATIENTS USING A 29-GAUGE NEEDLE: TECHNICAL CONSIDERATIONS AND AN EVALUATION OF POSTOPERATIVE COMPLAINTS COMPARED WITH GENERAL ANAESTHESIA

One hundred patients aged 18–49 yr, undergoing electivearthroscopy of the knee joint, were allocated randomly to eitherspinal anaesthesia using a 29-gauge spinal needle or generalanaesthesia. Dural puncture was considered difficult in 18%of the patients receiving spinal anaesthesia. In three patients(6%) it was necessary to supplement the spinal anaesthetic withgeneral anaesthesia. Spinal and general anaesthesia were otherwiseuneventful in all patients. The incidence of postoperative headachewas similar in the two groups. One patient developed post duralpuncture headache following spinal anaesthesia. This headachewas of short duration and disappeared without treatment. Spinalanaesthesia caused more backache than general anaesthesia, otherwisethe frequency of postoperative complaints was the same or lower.Ninety-six percent of the patients receiving spinal anaesthesiawould prefer the same anaesthetic for a similar procedure inthe future ^*Department of Anaesthesiology, Hvidovre University Hospital,DK-2650 Hvidovre, Copenhagen, Denmark     

Patient-controlled spinal analgesia for labour and caesarean delivery

Continuous spinal anaesthesia has not been widely used in Australia. Epidural anaesthesia is often inadequate in patients with previous spinal surgery, as distribution of local anaesthetic in the epidural space is unpredictable. Two cases are presented where continuous spinal anaesthesia enabled satisfactory analgesia and anaesthesia to be obtained for labour and caesarean delivery respectively.     

ACE inhibition does not exaggerate the blood pressure decrease in the early phase of spinal anaesthesia

BACKGROUND: This study investigates whether long-term treatment with an angiotensin converting enzyme inhibitor (ACEI) impairs the hemodynamic regulation during the early phase of spinal anaesthesia. METHODS: Forty-two patients undergoing minor surgery were studied. Twenty-one patients were long-term treated (ACEI group), while the other patients served as controls (nonACEI group). All patients received a balanced electrolyte solution (6 ml kg(-1)) 20 min before spinal anaesthesia. RESULTS: Mean arterial blood pressure decreased 19% in both groups within 20 min after spinal anaesthesia. Heart rate did not change in either group. Plasma renin concentration increased from 7.3 +/- 2.1 to 12.8 +/- 4 pg ml(-1) during spinal anaesthesia in nonACEI patients (P < 0.05), whereas an elevated plasma renin level remained unchanged in the nonACEI group. The angiotensin II concentration increased in both groups during spinal anaesthesia (P < 0.05). The vasopressin concentration did not change during spinal anaesthesia in the ACEI group, but increased from 1.2 +/- 0.3 to 2.2 +/- 0.5 pg ml(-1) in patients with ACEI treatment (P < 0.05). The norepinephrine concentration increased transiently 5 min after spinal anaesthesia in both groups, and returned to baseline levels within 15 min. CONCLUSION: Long-term ACEI treatment does not further exaggerate the blood pressure decrease in the early phase of spinal anaesthesia. The increase in vasopressin concentrations in ACEI treated patients seems to be sufficient to compensate for the inhibited renin-angiotensin system. In addition, the transient increase in plasma norepinephrine, which occurs independent of preoperative ACEI treatment, seems to be involved in blood pressure regulation during spinal anaesthesia.     

Spinalanästhesie und funktionale Sympathikusblockade

By measuring pulse rate (PR), blood pressure (BP), electrical integral skin resistance (SR), and skin surface temperature in different areas, the activity of the sympathetic nerves in spinal anaesthetics of different levels was evaluated. It was found that the sympathetic subsystems for vasomotor and sudomotor activity have their own innervation and that the functionally different effectors also manifest different deficiency reactions in low- and medium-level spinal anaesthesia. Functional sympathetic innervation, however, is unimportant after high sensory spread of spinal anaesthesia. The sympathetic nerves show similar signs of deficiency during administration of centrally acting general anaesthetics. In contrast to these, however, high spinal anaesthesia does not block the vagal component of the autonomic nervous system. The unopposed parasympathetic nerves directly affect the heart and other effectors, which may result in life-threatening cardiovascular reactions with decreases in BP and bradycardia. If high sympathetic blockade is recognized early, such life-threatening situations can be managed successfully. Suitable means of measuring sympathetic activity are the observation of BP, HR, temperature, and particularly SR at the hand. Sympathetic nerve blockade due to spinal anaesthesia first causes a reduction of SR in the lower extremity. In high spinal anaesthesia there is also a loss of sympathetic activity at the hands. Subsequently, hand temperature increases, and finally bradycardia and hypotension occur. The functional reaction of sympathetic activity is indicated by correlation of the vasomotor and sudomotor activities in high and low spinal anaesthesia. Failure of sudomotor activity can be observed on average at least 3 min prior to an increase in acral temperature and 9 min at the hands in cases of high spinal anaesthesia. The maximum increase in temperature in the feet was 4°?C in high spinal anaesthesia, which was equal to that measured at the hand during centrally acting general anaesthesia.     

Progression of first degree heart block to high-grade second degree block during spinal anaesthesia

A case is presented in which a patient with pre-existing first degree heart block developed high-grade second degree heart block during spinal anaesthesia. Progression of the block was associated with blockade of cardiac sympathetic neurons induced by spinal anaesthesia. This suggests that patients with pre-existing heart block may be at increased risk for development of higher grade block during spinal anaesthesia.