Comparison of double-segment technique with single-space technique for cesarean section using combined spinal epidural anesthesia

In patients scheduled for cesarean section (c-section) using combined spinal epidural anesthesia (CSEA), we compared the cephalad spreading speed during double-segment technique (DST) with that of single-space technique (SST) of CSEA. In the patients of SST group (n = 169), a 17-G Tuohy needle was introduced at the L 3-4, and then a long spinal needle was inserted through the Tuohy needle. In the patients of DST group (n = 16), a Tuohy needle was introduced at the T 11-12, and a spinal needle was inserted at the L 3-4. After 0.3% hyperbaric dibucaine 1.0 ml was injected through the spinal needle, 1.5% mepivacaine 10 ml was injected through the epidural catheter in both the groups. The analgesic level was measured at 5-min intervals, and blood pressure and complaints of patients were also recorded. The cephalad spread of analgesia was significantly higher in DST group than in SST group at 5 and 10 min after the administration of local anesthetics. Two patients in SST group, epidural catheterization was not possible. There were no difference in the incidences of hypotension, nausea and dyspnea between the groups. We conclude from these results that DST for CSEA is preferable to SST for c-section.     

Paediatric lumbar epidurals: a comparison of 21-G and 23-G catheters in patients weighing less than 10 kg

Using the database of our pain management team, we examined the records of 254 patients weighing between 4.5 kg and 10 kg who received an epidural for postoperative analgesia. We looked at the incidence of catheter related problems in two groups of patients in whom either a 21-G (18-G short Tuohy needle) or a 23-G catheter (19-G short Tuohy needle) was used. There was a significantly higher incidence of difficulty in threading the catheter, kinking and occlusion in the 23-G catheter group. There were more leaks in the 21-G catheter group but the difference was not significant and both groups had a comparable incidence of clinically relevant leakages. No dural tap or difficulty in using either needle were reported.     

Extradural and subarachnoid catheterization using the Seldinger technique

The Seldinger technique was developed using a plastic introducer through which introduction and manipulations of a silicone spinal catheter, an extradural stimulation lead or a small diameter fibreoptic scope are possible without the risk of damage to the vulnerable devices. It is not intended as a replacement of the standard technique of introducing a spinal catheter through a Tuohy needle in general anaesthetic practice. Silicone spinal catheters and stimulation leads are used for long-term therapy in intractable chronic pain and spasticity. A fibreoptic scope is used for endoscopic examination of the subarachnoid or extradural space. Using a standard Tuohy needle the soft silicone extradural lead can be damaged easily by manipulations during insertion. For this reason the manufacturer modified the Tuohy needle for extradural silicone lead introduction. The disadvantages of this modified Tuohy needle are: first, difficulty in localization of the extradural space, second, the needle is unsuitable for a subarachnoid catheter or introduction of a fibreoptic scope. The Seldinger technique was performed 25 times in 18 patients, introducing a spinal silicone catheter (n = 14), an extradural silicone stimulation lead (n = 2) or a small diameter fibreoptic endoscope (n = 9). Paraesthesiae caused by neural irritation occurred in awake patients. This did not differ from the technique using a Tuohy needle only. Neural damage or trauma did not occur with the Seldinger technique. The incidence of post-spinal headache was the same for both techniques. No further complications were noted.      

Epidural injection of lidocaine reduces the response to dural puncture accompanying spinal needle insertion when performing combined spinal-epidural anesthesia

During placement of needles for combined spinal-epidural anesthesia (CSEA), patients may experience pain, pressure, paresthesia, or discomfort during skin and deeper injection of local anesthetic, needle impingement on periosteum, dural puncture by the spinal needle, and insertion of the epidural catheter. We investigated the incidence of perception of and spontaneous verbal and motor responses to insertion of a spinal needle through the dura mater and pia mater and the effect of injecting lidocaine into the epidural space through the epidural needle before inserting the spinal needle through the meninges. Forty-three patients presenting for elective cesarean delivery under CSEA were studied. After localization of the epidural space using loss of resistance to air using a 17-gauge Tuohy needle, either 3 mL preservative free normal saline or 3 mL lidocaine 2% plus epinephrine 1:200,000 was injected through the Tuohy needle. "Needle through needle" dural puncture was performed 1 min later using a 27-gauge Whitacre pencil-point needle. At the moment of dural puncture, 2 (9%) parturients given lidocaine and 17 (81%) parturients given saline (P < 0.005) responded to dural puncture by spontaneously moving (33%), spontaneously vocalizing (62%), or, in response to direct questioning, by acknowledging (76%) having perceived sensation during thecal penetration. This study reveals that dural puncture by a Whitacre 27-gauge pencil-point needle inserted through a Tuohy epidural needle sited using loss of resistance to air causes involuntary movement, spontaneous vocalization, or is perceived by the majority of patients presenting for cesarean delivery under CSEA and that lidocaine injected into the epidural space before dural puncture largely eliminates these responses and sensations.     

A comparison of Espocan and Tuohy needles for the combined spinal-epidural technique for labor analgesia

When using the needle-through-needle combined spinal-epidural (CSE) technique for labor analgesia, failure to obtain cerebrospinal fluid (CSF), paresthesias, and intrathecal or intravascular migration of the catheter are of concern. Epidural needles with spinal needle apertures, such as the back-hole Espocan (ES) needles, are available and may reduce these risks. We describe the efficacy and adverse events associated with a modified epidural needle (ES) versus a conventional Tuohy needle for CSE. One-hundred parturients requesting labor analgesia (CSE) were randomized into 2 groups: 50-ES 18-gauge modified epidural needle with 27-gauge Pencan atraumatic spinal needle, 50-conventional 18-gauge Tuohy needle with 27-gauge Gertie Marx atraumatic spinal needle. Information on intrathecal or intravascular catheter placement, paresthesia on introduction of spinal needle, failure to obtain CSF through the spinal needle after placement of epidural needle, unintentional dural puncture, and epidural catheter function was obtained. No intrathecal catheter placement occurred in either group. Rates of intravascular catheter placement and unintentional dural puncture were similar between the groups. Significant differences were noted regarding spinal needle-induced paresthesia (14% ES versus 42% Tuohy needles, P = 0.009) and failure to obtain CSF on first attempt (8% ES versus 28% Tuohy needles, P < 0.02). Use of ES needles for CSE significantly reduces paresthesia associated with the insertion of the spinal needle and is associated with more frequent successful spinal needle placement on the first attempt. IMPLICATIONS: The use of modified epidural needles with a back hole for combined spinal-epidural technique significantly reduces paresthesia associated with the insertion of the spinal needle and is associated with more frequent successful spinal needle placement on the first attempt.     

Eine atraumatische Kanüle für die kontinuierliche Peridural- und Plexusanästhesie

The needle type introduced by Edward Tuohy for continuous spinal anaesthesia in 1944 is still used as the standard instrument for epidural anaesthesia up to the present day. Puncture of the dura and severance of the epidural catheter are the typical, though rare, complications of this procedure, giving rise to most of the actions brought for damage suffered during obstetic anaesthesia. The cerebral spinal fluid loss caused by thick needles can have serious consequences, including subdural and intracranial haematoma, cranial nerve pareses, labyrinthine hearing impairments and pneumocephalus. Special Sprotte needle for catheter introduction. In spinal anaesthesia and lumbar puncture the Sprotte needle has proven a very suitable instrument for prevent the CSF loss syndrome and, to a large degree, post-spinal headaches. To adapt the atraumatic properties of this needle point for epidural anaesthesia, the needle has been equipped with a plastic ramp to direct catheter insertion, and the opening geometry has been slightly modified for epidural application (see Fig.?1). The lateral catheter channel projects into the base of the needle point, which is thus shortened, and the edges of the needle opening are rounded so that the catheters cannot be severed. This needle bears the type designated ?Special Sprotte needle“ (EP no. 271715, USP no. 4842585). Needle diameter and application fields. The 1.1-mm (19.5?G) needle with 23-G catheter was introduced for epidural anaesthesia and continuous plexus anaesthesia at the Würzburg University Hospital and has proven itself in routine clinical practice. A 20-G version is being tested with a 25-G catheter for continuous spinal anaesthesia at several centers in USA, because finer spinal catheters are not permitted there by the FDA. For continuous spinal anaesthesia this needle has been available without the modified opening geometry since 1989 in sizes 22 G and 24 G and is wide by used in Europe. CSE technique with special and standard Sprotte needles. Spinal analgesia or anaesthesia (combined spinal-epidural anaesthesia) can be performed with the special needle and 123-mm-long 27 G or 29 G standard Sprotte needles before placement of the peridural catheter.     

Combined spinal and epidural anesthesia for orthopaedic surgery in the elderly]

The pros and cons as to which anesthesia is more beneficial, either spinal or epidural, prompted us to perform combined spinal and epidural block in the elderly undergoing lower limb surgery. The selected epidural space was entered with a 17-gauge Tuohy needle and a longer 26-gauge spinal needle was passed through it and into the subarachnoid space. Following the injection of required dose of 2% preservative-free lidocaine (isobaric), spinal needle was withdrawn and an epidural catheter was inserted. We could use this combined technique on 17 patients older than 80 yr (mean age; 84.5 +/- 3.9 years) with satisfactory results and without any serious cardiovascular change, as with 17 middle-aged patients (57.5 +/- 5.2 years). This combination of techniques provides a rapid onset and reliability of spinal block with high quality analgesia by supplementation through the epidural catheter during and after surgery. In the orthopaedic procedures on the lower limbs, combined spinal and epidural block is more useful even for the elderly over the age of 80 yr than spinal or epidural anesthesia alone.     

Spinal epidural anaesthesia

We present our experience with a new combined spinal epidural system through which regional anaesthesia was performed in 30 male patients undergoing suprapubic prostatectomy. The technique consists of two needles, a 17 G Tuohy needle with a hole in its distal curve (back eye) and a 29 G spinal needle which is passed through the back eye before being introduced into the subarachnoid space. We found the back eye combined spinal-epidural system effective and simple to use. The Tuohy needle with its back eye did not impede insertion of the epidural catheter and was a suitable introducer for the thin 29 G spinal needle.     

The techniques to identify the epidural space do not influence the success rate in combined spinal-epidural anesthesia: a comparison between loss-of-resistance and hanging-drop]

The hanging-drop (HD) technique has been attributed to a negative epidural pressure induced by making a tent of the dura by the Tuohy needle. We, therefore, hypothesized that the HD technique would result in more successful intrathecal placement of the spinal needle in combined spinal-epidural anesthesia (CSEA) compared with the loss-of-resistance (LR). Seventy patients received CSEA using the needle-through-needle method with a spinal needle extending 9 mm beyond the Tuohy needle. Success rate in obtaining cerebrospinal fluid (CSF) at the first attempt was considerably low; 60% in HD and 57% in LR, which was not significantly different. Failure to obtain CSF after 3 attempts was not significantly different between the two techniques; 26% and 31% in HD and LR, respectively. In conclusion, there was no advantage of the HD technique for obtaining CSF in CESA compared with the LR. It seems that spinal needle length beyond the Tuohy needle should be more than 9 mm.     

A comparison between midline and paramedian approaches for combined spinal-epidural anesthesia]

We compared midline approach with paramedian approach for combined spinal-epidural anesthesia (CSEA) by needle through needle technique. Seventy patients undergoing elective gynecological surgery received CSEA with a 27 G Whitacre spinal needle, which protrudes 12 mm beyond the tip of the Tuohy needle. The successful subarachnoid puncture with first attempt was noted in 33 patients (94%) of midline group (M group), in 31 patients (89%) of paramedian group (P group). At the subarachnoid puncture, skin to epidural space distance (43.2 mm vs 53.4 mm) and protrusion length of spinal needle (5.5 mm vs 8 mm) were significantly longer in the P group than in the M group. Abdominal radiography revealed the flexion of epidural catheter in 19 patients (54%) of M group and in 2 patients (6%) of P group. The choice of midline or paramedian approach for CSEA did not affect the success rate of the subarachnoid puncture, but paramedian approach required longer protrusion length of the spinal needle than midline approach. To raise the success rate of subarachnoid puncture by paramedian approach, a long protruded spinal needle is recommended.     

Coiling of lumbar epidural catheters

BACKGROUND: The difficulties in threading an epidural catheter to vertebral levels remote to the puncture level have been well documented. This study was undertaken to determine the length that a single orifice epidural catheter can be threaded into the lumbar space without coiling (coiling length), and whether this is affected by the direction of the epidural needle bevel. METHODS: Forty-five young male patients scheduled for surgery under epidural analgesia were enrolled. The epidural space was identified using a midline approach at the L(2-3) or L(3-4) interspace with the loss of resistance to air technique. A 19-G single-orifice epidural catheter (Flextip Plus, Arrow International, Inc, Reading, PA, USA) was inserted through a Tuohy needle oriented either cephalad (n=20) or caudad (n=25). During insertion, the path and the position of the catheter tip was determined by fluoroscopy using iohexol dye. RESULTS: The median coiling length was 2.8 cm, ranging from 1.0 to 8.0 cm. Only 13% of epidural catheters could be threaded 4 cm beyond the tip of the needle without coiling. No significant difference was found in coiling length between the cephalad group (2.9 cm) and the caudad group (2.5 cm). CONCLUSION: This study demonstrates that coiling length is independent of whether the bevel of the Tuohy needle is directed cephalad or caudad. We recommend that an optimal insertion depth of an end-hole single orifice catheter is 3 cm.     

Tunneled lumbar drain. Technical note

The authors report a simple and rapid procedure for tunneling a lumbar drain subcutaneously to facilitate chronic cerebrospinal fluid (CSF) drainage. A standard lumbar puncture (LP) is performed with a large-bore Tuohy needle (14- to 16-gauge), the drainage catheter is advanced into the subarachnoid space, and the needle is removed. The free Tuohy needle is then passed from a lateral position and brought out through the initial LP site. The free catheter is fed through the needle, and the needle is removed. The drain is attached to an external drainage bag in the usual manner. The authors have found this method particularly useful in some skull base and spinal surgical applications in which longer term continuous CSF drainage is desired.     

Evaluation of a lockable combined spinal-epidural device for use with needle-through-needle technique

BACKGROUND: Recently, a new combined spinal-epidural (CSE) device has been introduced which allows the spinal needle to be extended a maximum of 15 mm beyond the Tuohy needle and locked onto the epidural needle after dural puncture. The aim of this study was to compare this lockable CSE device with the conventional CSE device, which allows the spinal needle to be extended 9 mm beyond the Tuohy needle, and to measure the length of the protrusion of the spinal needle beyond the Tuohy needle (top-to-top distance: TTD). METHODS: We studied sixty patients scheduled to undergo elective gynecological surgery and cesarean section. Patients were divided into three groups: patients in Group I (n = 20) using the conventional CSE device in gynecological surgery; patients in Group II (n = 20) using the lockable CSE device in gynecological surgery; and patients in Group III (n = 20) using the lockable CSE device in cesarean section. RESULTS: The success rate of spinal anesthesia with needle-through-needle technique was higher with the lockable CSE device (100%) than with the conventional CSE device (75%). The TTD was 7.9 +/- 1.8 (SD) cm in non-pregnant group (Group II) and 8.7 +/- 1.5 cm in pregnant group (Group III). This difference was not statistically significant. In the lockable CSE device groups (Group II and III), 10 patients (25%) had a TTD of 10 mm or more. CONCLUSIONS: The lockable CSE device improves the success rate of spinal anesthesia in needle-through-needle CSE anesthesia.     

Relationship between the bevel of the Tuohy needle and catheter direction in thoracic epidural anesthesia

BACKGROUND AND OBJECTIVES: Directing an epidural catheter cephalad or caudad is usually attempted by orienting the beveled edge of the epidural needle. However, there have been few studies about the relationship between the direction of the bevel of epidural needle and the resulting position of the catheter. We studied this relationship in thoracic epidural catheter placement. Catheter position was confirmed by using picture archiving communication systems (PACS). PACS is a workstation that stores radiologic images, which can be manipulated to visualize the catheters. METHODS: One hundred six patients receiving thoracic epidural anesthesia were enrolled. The cephalad and caudad groups (each with 53 patients) received epidural anesthesia at the T6-7 interspace with either a cephalad- or caudal-directed Tuohy needle. The final position of all of the catheters was confirmed by PACS. RESULTS: In the cephalad group, 63.5% of the catheters were confirmed to travel in a cephalad direction. In the caudad group, 22.0% of the catheters advanced in a caudad direction. Curling of the catheters occurred in 17.6%. PACS showed the catheter positions with satisfactory quality. CONCLUSIONS: The correlation between bevel direction and location of the thoracic epidural catheter was relatively low. Practices such as threading an epidural catheter by manipulation of the Tuohy needle for the control of pain at a distant site may not yield good results.     

No additional metal particle formation using the needle-through-needle combined epidural/spinal technique

Background. Combined epidural/spinal analgesia utilizing a needle-through-needle technique has become very popular in anesthesia. However, findings of concave deformities at the orifice of Tuohy needles after spinal needle passage have raised concerns that metal fragments might be deposited within the epidural space. This study was proposed to investigate whether the needle-through-needle technique does produce metallic flecks.
Methods. Ten unused Tuohy and Hustead epidural needles were inspected microscopically and photomicrographed prior to flushing saline through each into a single tissue culture well. After drying, a single pass was made with a 120 mm 24-gauge Sprotte needle through each epidural needle to maximal extension while the orifice was within another tissue culture well. Each needle was again flushed into a third well before reexamination and photomicroscopy. Each of the wells was inspected for metallic particles by microscopy. Additional freshly unpackaged Tuohy needles were microscopically examined after exposure to a magnetic field.
Results. Comparison of micrographs before and after needle experiments revealed concave deformities at the orifice of all the Tuohy and Hustead needles. No particles were observed in either of the two saline-flushed wells or within the well in which the needle-through-needle passes were made. Inspection of unused Tuohy needles exposed to a magnetic field revealed metal filings "standing up" along the bevel of every needle examined.
Conclusions. Metallic particles are not produced by the needle-through-needle technique. However, metal particles are an apparent contaminant of all epidural needles and are probably routinely introduced into patients when the needle is placed.     

The lumbar subdural extraarachnoid space of humans: an anatomical study using spinaloscopy in autopsy cases

The lumbar subdural extraarachnoid space was examined by spinaloscopy in 15 autopsy subjects. Special attention was paid to the ease with which the space opened up and also to the extent of view achieved. In ten cases the space opened up with ease, in four cases with difficulty, and in one case it was not possible to establish the subdural space at all. The bevel of an 18-gauge Tuohy needle introduced into the subdural space could be visualized in eight of 13 cases. An epidural catheter was then passed through the Tuohy needle into the subdural space in eight cases and was visualized in six of them. Although care must be exercised in drawing conclusions for clinical epidural anesthesia from autopsy cases, this study confirms the possibility of placing both the bevel of a Tuohy needle and an epidural catheter in the subdural space. The results reemphasize the need for caution suggested by other reports regarding the possibility of subdural puncture in epidural anesthesia and subsequent injection of anesthetic solution into the subdural space.     

Comparison of three catheter sets for continuous spinal anesthesia in patients undergoing total hip or knee arthroplasty

BACKGROUND AND OBJECTIVES: Continuous spinal anesthesia (CSA) with microcatheters may be complicated because of technical problems. In elderly patients, some of the problems may be solved by using thicker catheters. A recent invention, involving a catheter-over-needle system, may prevent leakage of cerebrospinal fluid (CSF) and may also improve the prediction of the intrathecal position of the catheter tip. METHODS: This study included 90 patients undergoing primary hip or knee replacement, randomly allocated into 3 groups, with 30 patients in each group: Group EC, a 24-gauge epidural catheter through a 19-gauge Tuohy needle; group MC, a 28-gauge microcatheter through a 22-gauge spinal needle; group SC, a 22-gauge spinal catheter over a 27-gauge spinal needle through an epidurally placed 18-gauge Crawford needle. All subarachnoid catheterizations were performed with the patient in the lateral position and the initial spinal block dose was 2 mL of plain 0.5% bupivacaine. Increments of 0.5 mL were administered when required. The block performance characteristics were recorded, and the level of analgesia was studied in a blinded fashion. Catheter function during the postoperative infusion was assessed. Afterwards the needles and catheters were examined by microscopy. RESULTS: The frequency of the successful catheterization was higher in the EC and MC groups (90% in each) than in the SC group (63%) (P <.05). The mean duration of the successful catheterizations, as well as the median level of analgesia, were similar in the groups. The postoperative infusion had to be stopped in 3, 1, and 1 patients in groups EC, MC, and SC, respectively, because of a technical reason. No neurologic sequelae occurred in this study. Microscopy showed 4 distorted spinal needle tips (2 each with MC and SC) and minor material damage of the SC catheters when bone had been met during block performance. CONCLUSIONS: Placement of the SC catheters was unsuccessful to a high degree, and bone contact produced distortion of the tip of some of these catheters. Otherwise, the quality associated with catheterization time, anesthetic distribution, and catheter function was similar with the 3 catheters.     

Comparison of continuous spinal and epidural analgesia for pain relief in labour

We have compared continuous spinal analgesia with continuous epidural analgesia for pain relief in labour. Twenty-six women were randomly allocated to receive either epidural 0.25% bupivacaine 5-10 ml via a 20 gauge catheter inserted through a 16 gauge Tuohy needle or intrathecal 0.25% bupivacaine 0.5-1.0 ml via a 32 gauge catheter inserted through a 24 gauge Sprotte needle. This was supplemented with fentanyl 5-10 mcg (spinal) or 1 mcg per kg (epidural) if analgesia was unsatisfactory. Outcome was measured by the success and timing of the procedure, time to analgesia, amount of drug given, visual analogue scoring of pain relief by the patient and an observer and degree of motor block. Onset time and dosage were significantly reduced in the continuous spinal group. Two catheters failed to feed in the spinal group. One catheter became displaced in each group. Pain relief was satisfactory in all patients and none had post-dural puncture headache. Continuous spinal analgesia may offer significant advantages over epidural analgesia but technical difficulties remain with the present equipment. The reasons for the withdrawal of the spinal catheters in the United States of America are discussed.     

Thoracic epidural pressure and peripheral venous pressure in the lower extremity during supine hypotensive syndrome

BACKGROUND: After induction of spinal anesthesia, thoracic epidural pressure and left saphenous venous pressure were monitored and recorded during supine hypotensive syndrome in 8 pregnant patients who underwent elective cesarean section. METHODS: A 22 G venous catheter was inserted into the left saphena, and an epidural catheter for 18 G needles was positioned 5 cm cephalad in the epidural space through a Tuohy needle at the T 11-12 intervertebral space. Each catheter was connected to a pressure transducer, and recording was started in a supine position immediately after induction of spinal anesthesia with 0.5% isobaric bupivacaine at the L 3-4 intervertebral space. RESULTS: In all patients, epidural pressure and peripheral venous pressure synchronously increased as soon as they began to recover from hypotension and tachycardia regardless of uterine displacement to the left. CONCLUSIONS: The synchronous increase in both pressures was late after the hypotension probably because sympathetic block with spinal anesthesia inhibited vasoconstriction of the lower extremity, a factor to compensate for supine hypotensive syndrome. Only collateral flow via epidural venous plexus emptying into azygos system could not compensate for decreased venous return to the right atrium from obstructed inferior vena cava, and differences in the degree of compression of the inferior vena cava by gravid uterus would affect the recovery from supine hypotension.     

Technical problems associated with the use of 32-gauge and 22-gauge spinal catheters

Interest in the use of continuous spinal anaesthesia (CSA) has recently increased because of the availability of new, extremely thin catheters. In this study the use of 32-gauge (G) catheters was compared with 22-G catheters in operations on the lower limb and for the administration of intrathecal morphine in the postoperative period in 42 elderly patients. CSA succeeded in 34 cases and 8 patients were anaesthetised with a single-shot spinal method. No general anaesthesia was needed. Technical problems with the subarachnoid puncture with the 19-G needle caused two failures in the 22-G group. In a group of 20 patients, there were five failures with the 32-G catheter, as opposed to one failure with the 22-G catheter in a group of 20 patients. Associated with morphine injection through the 32-G catheter, the syringe or connector was inadvertently disconnected in four cases and a tear of the catheter wall was observed in one case. Such problems did not occur with the 22-G catheter. Postdural puncture headache did not occur, and there was no difference in the incidence of patient-reported postoperative complications between the two groups. It is concluded that both the insertion and maintenance of the thin (32-G) subarachnoid catheters are associated with more technical problems than the 22-G catheter.