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.     

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.     

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.     

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.     

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.     

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.     

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.     

Spinal and epidural anaesthesia for caesarean section in patients with pre-eclampsia

Neuraxial regional anaesthesia is now widely used in obstetric anaesthesia. Specifically, the rate of spinal anaesthesia increased considerably and is favoured for scheduled caesarean section. Former concerns to use regional anaesthetic techniques in non scheduled cases, e.g. spinal anaesthesia for pre-eclampsia are not supported by recent study data. Spinal and epidural anaesthesia are both safe in patients presenting with pre-eclampsia, if contraindications for neuraxial anaesthesia are taken into account.     

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.     

Cost estimates of spinal versus general anaesthesia for fractured neck of femur surgery

It remains uncertain whether spinal anaesthesia is preferable to general anaesthesia for surgical repair of hip fracture, but one determining factor is the comparative cost. A detailed cost analysis relating to 20 consultants’ intended anaesthetic practice (which provided information of consumables used) and data from the Brighton Hip Fracture Database was performed to quantify any difference in the costs of administering spinal versus general anaesthesia for patients with hip fracture. Although spinal anaesthesia took significantly longer to administer (mean (SD) time 31 (15) min vs 27 (16) min; p < 0.0001), the mean (SD) cost of spinal anaesthesia (£193.81 (37.49)) was significantly less than the cost of general anaesthesia (£270.58 (44.68); p < 0.0001). The mean percentage cost of anaesthesia was 3.8% of hospital income per hip fracture, and personnel contributed approximately 46% of this cost. While such considerations indicate that spinal anaesthesia is financially preferable, it is unknown whether differential clinical outcomes between regional and general anaesthesia may offset this apparent monetary advantage.     

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.     

Restricted spinal anaesthesia for ambulatory surgery: a pilot study

The increasing use of ambulatory surgery requires methods of anaesthesia that allow patients to be discharged soon after the operation is completed. Spinal anaesthesia is usually simple and quick, and the incidence of post-spinal headache has been reduced by using non-cutting small-gauge needles. Limiting the spread of spinal anaesthesia, as long as it still provides analgesia for surgery, should reduce the haemodynamic effects and speed recovery. Restricted spinal anaesthesia, intended to be unilateral using 0.18% hypobaric bupivacaine via a 25G or 27G Whitacre unidirectional needle, was compared with epidural anaesthesia (using a mixture of lignocaine and prilocaine) in 64 matched-pair patients undergoing ambulatory arthroscopy. Motor blockade, assessed for the specific myotomes L2 to S1, was significantly more unilateral in the spinal group. Two patients in the spinal group and nine patients in the epidural group were treated for hypotension (P < 0.05). One patient in the spinal group developed a post-spinal headache. One patient in the epidural group rated the anaesthesia poor.     

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.     

Failed spinal analgesia after a combined spinal epidural anaesthesia for Caesarean section

A case of failed spinal analgesia with a combined spinal epidural anaesthesia (CSE) for Caesarean section is described. The lack of desired effect following an inconspicuous spinal, epidural or combined regional anaesthesia by an experienced anaesthetist is a rare and unexpected event. Especially when repeatedly observed in one patient,one should consider modified anatomical conditions of the affected spinal regions. We discuss the differential diagnosis which consists of inherent and acquired modification of tissue, neoplasia and vascular or infectious diseases. This case also confirms that not every adverse event after spinal or extradural anaesthesia is necessarily caused by the puncture.     

Spinal anaesthesia in paediatrics

The use of spinal anaesthesia in children has been primarily limited to situations in which general anaesthesia was considered to pose an excessive risk. The ex-premature infant and the neurologically impaired child account for the majority of spinal anaesthetics used today. Spinal anaesthesia, compared with general anaesthesia, in the ex-premature infant undergoing inguinal hernia repair has decreased postoperative respiratory complications (e.g. apnoeic events, prolonged mechanical ventilation). Hyperbaric tetracaine and bupivacaine solutions are the local anaesthetics of choice. Haemodynamic stability is well preserved in neonates having spinal anaesthesia. Advances in spinal needle design have decreased the incidence of postdural puncture headache (PDPH). Catastrophic events have occurred with neuraxial techniques. Care must be taken in evaluating the relative risks of anaesthetic approaches in infants and children.     

Comparative study of general and spinal anesthesia in elderly women in hip surgery

The choice between regional versus general anaesthesia for elderly patients undergoing hip surgery is debated. It is vitally important to see if the type of anaesthetic administered affects per- and postoperative morbidity and mortality. Seventy women more than 75 yr old suitable for spinal anaesthesia were included in this study. They were randomly divided into two groups: in one (n = 35), general anaesthesia was given with sodium thiopentone, fentanyl, enflurane and vecuronium; in the other (n = 35), spinal anaesthesia was performed with 3 ml 0.5% bupivacaine in isobaric solution. During the anaesthetic period, there were no statistically significant differences between both groups in systolic arterial pressure falls or in increases in the heart rate X systolic arterial pressure product. No serious cardiovascular collapse was encountered. Seven patients (20%) receiving general anaesthesia had mental changes against four only (14.2%) in the spinal group. In patients having general anaesthesia, 22.9% developed bronchopneumonia as opposed to 8.6% in the spinal anaesthesia group (p less than 0.05). The mortality rate at three months was rather similar in the two groups. It was concluded that, in order to reduce the incidence of postoperative central dysfunction and bronchopneumonia, spinal anaesthesia should be preferred in geriatric patients for lower limb surgery.     

Sympathovagal effects of spinal anaesthesia with intrathecal or intravenous fentanyl assessed by heart rate variability

Background: Although many investigators previously reported the sympathovagal effect of spinal anaesthesia, there is no information about the sympathovagal effects of supplementation with fentanyl. The aim of this study was to evaluate the sympathovagal effects of intrathecal or intravenous fentanyl added to spinal anaesthesia.
Methods: One hundred and twenty patients undergoing elective transurethral surgery under spinal anaesthesia were randomly allocated to receive intrathecally either isobaric bupivacaine alone (Group B), bupivacaine supplemented with intrathecal (Group Ft) or with intravenous fentanyl (Group Fv). Heart rate variability was estimated using the MemCalc method (Tarawa, Suwa Trust, Japan) before and after spinal anaesthesia.
Results: In all groups, spinal anaesthesia significantly decreased low frequency/high frequency (LF/HF) as a marker of sympathovagal balance. However, patients in Group B with a low block height developed a marked increase in LF/HF after spinal anaesthesia, which was attenuated in Group Ft. Meanwhile, intravenous fentanyl did not attenuate this response.
Conclusion: We conclude that sympathetic activation observed in patients with a low block height was attenuated by intrathecal fentanyl but not by intravenous fentanyl.