[Diagnosis and treatment of 18 cases of Chiari malformation with hoarseness]

Objective: To investigate the diagnosis and treatment of Chiari malformation patients with hoarseness and other otorhinolaryngological symptoms. Methods: The clinical data of 18 patients of Chiari malformation with hoarseness were retrospectively collected, which was composed of 5 men and 13 women, aged 3-71 with median age of 52. All the patients were admitted to the Affiliated Hospital of Qingdao University from January 1989 to January 2020. All patients underwent brain MRI and laryngoscopy. The patient's symptoms and first diagnosis department, diagnosis time, total course of disease, hoarseness course, diagnosis and treatment, and postoperative recovery time were summarized. Follow-up time was 3-16 years, with median follow-up time of 6.5 years. Descriptive methods were used for analysis. Results: The first visit departments of 18 patients included neurology (9 cases), otorhinolaryngology head and neck surgery (5 cases), pediatrics (2 cases), orthopedics (1 case) and respiratory department (1 case). Except for the 7 cases in neurology department, the other 11 patients were not diagnosed in time. The disease duration of 18 patients with Chiari malformation ranged from 2 months to 5 years, and hoarseness was present from 20 days to 5 years. After diagnosis, 9 patients underwent posterior fossa decompression surgery, and 1 of them underwent syrinx drainage at the same time. The symptoms of 8 cases improved significantly after operation, with the improvement time from 1 to 30 days. In addition, 9 patients chose conservative treatment, among whom 8 had no improvement in symptoms and 6 progressed. Conclusions: Posterior fossa decompression is an effective treatment for Chiari malformation, and the prognosis is good. Timely diagnosis and treatment can improve the prognosis of patients.

Clonal Expansion of Stem/Progenitor Cells in Cancer, Fibrotic Diseases, and Atherosclerosis, and CD47 Protection of Pathogenic Cells

We proposed and demonstrated that myelogenous leukemia has a preleukemic phase. In the premalignant phase, normal hematopoietic stem cells (HSCs) gradually accumulate mutations leading to HSC clonal expansion, resulting in the emergence of leukemic stem cells (LSCs). Here, we show that preleukemic HSCs are the basis of clonal hematopoiesis, as well as late-onset blood diseases (chronic-phase chronic myeloid leukemia, myeloproliferative neoplasms, and myelodysplastic disease). The clones at some point each trigger surface expression of "eat me" signals for macrophages, and in the clones and their LSC progeny, this is countered by upregulation of "don't eat me" signals for macrophages such as CD47,opening the possibility of CD47-based therapies. We include evidence that similar processes result in fibroblast expansion in a variety of fibrotic diseases, and arterial smooth muscle clonal expansion is a basis of atherosclerosis, including upregulation of both "eat me" and "don't eat me" molecules on the pathogenic cells.

Modifiable risk factors in the first 1000 days for subsequent risk of childhood overweight in an Asian cohort: significance of parental overweight status

BACKGROUND/OBJECTIVE

Many studies have identified early-life risk factors for subsequent childhood overweight/obesity, but few have evaluated how they combine to influence risk of childhood overweight/obesity. We examined associations, individually and in combination, of potentially modifiable risk factors in the first 1000 days after conception with childhood adiposity and risk of overweight/obesity in an Asian cohort.

METHODS

Six risk factors were examined: maternal pre-pregnancy overweight/obesity (body mass index (BMI) ⩾25 kg m^-2), paternal overweight/obesity at 24 months post delivery, maternal excessive gestational weight gain, raised maternal fasting glucose during pregnancy (⩾5.1 mmol l^-1), breastfeeding duration <4 months and early introduction of solid foods (<4 months). Associations between number of risk factors and adiposity measures (BMI, waist-to-height ratio (WHtR), sum of skinfolds (SSFs), fat mass index (FMI) and overweight/obesity) at 48 months were assessed using multivariable regression models.

RESULTS

Of 858 children followed up at 48 months, 172 (19%) had none, 274 (32%) had 1, 244 (29%) had 2, 126 (15%) had 3 and 42 (5%) had ⩾4 risk factors. Adjusting for confounders, significant graded positive associations were observed between number of risk factors and adiposity outcomes at 48 months. Compared with children with no risk factors, those with four or more risk factors had s.d. unit increases of 0.78 (95% confidence interval 0.41-1.15) for BMI, 0.79 (0.41-1.16) for WHtR, 0.46 (0.06-0.83) for SSF and 0.67 (0.07-1.27) for FMI. The adjusted relative risk of overweight/obesity in children with four or more risk factors was 11.1(2.5-49.1) compared with children with no risk factors. Children exposed to maternal pre-pregnancy (11.8(9.8-13.8)%) or paternal overweight status (10.6(9.6-11.6)%) had the largest individual predicted probability of child overweight/obesity.

CONCLUSIONS

Early-life risk factors added cumulatively to increase childhood adiposity and risk of overweight/obesity. Early-life and preconception intervention programmes may be more effective in preventing overweight/obesity if they concurrently address these multiple modifiable risk factors.

Best practice guidelines for the operation of a donor human milk bank in an Australian NICU

Until the establishment of the PREM Bank (Perron Rotary Express Milk Bank) donor human milk banking had not occurred in Australia for the past 20 years. In re-establishing donor human milk banking in Australia, the focus of the PREM Bank has been to develop a formal and consistent approach to safety and quality in processing during the operation of the human milk bank. There is currently no existing legislation in Australia that specifically regulates the operation of donor human milk banks. For this reason the PREM Bank has utilised existing and internationally recognised management practices for managing hazards during food production. These tools (specifically HACCP) have been used to guide the development of Standard Operating Procedures and Good Manufacturing Practice for the screening of donors and processing of donor human milk. Donor screening procedures are consistent with those recommended by other human milk banks operating internationally, and also consistent with the requirements for blood and tissue donation in Australia. Controlled documentation and record keep requirements have also been developed that allow complete traceability from individual donation to individual feed dispensed to recipient and maintain a record of all processing and storage conditions. These operational requirements have been developed to reduce any risk associated with feeding pasteurised donor human milk to hospitalised preterm or ill infants to acceptable levels.

Intraoperative loading attenuates nausea and vomiting of tramadol patient-controlled analgesia

PURPOSE

To evaluate the adverse effect profile of tramadol by patient-controlled analgesia (PCA) with administration of the loading dose either intraoperatively or postoperatively.

METHODS

Sixty adult patients scheduled for elective abdominal surgery were enrolled into this prospective, randomized, double blind study. The patients were anesthetized in a similar manner. At the beginning of wound closure, the patients were randomly allocated to receive 5 mg x kg(-1) tramadol (Group 1) or normal saline (Group 2). In the post-anesthesia care unit (PACU), when patients in either group complained of pain, 30 mg x ml(-1) tramadol i.v. were given every three minutes until visual analogue scale (VAS) 3, followed by tramadol PCA with bolus dose of 30 mg and five minute lockout interval. Pain control and adverse effect assessments were done in the PACU and every six hours for 48 hr post drug by an independent observer.

RESULTS

The loading dose was 290 +/- 45 mg in Group 1 and 315 +/- 148 mg in Group 2. In PACU, more nausea/vomiting both in terms of incidence (13/30, 43% vs 2/30, 6.6%, P < 0.05) and severity (nausea/vomiting score 2.5 +/- 2.0 vs 0.2 +/- 0.6, P < 0.05) was observed in patients with postoperative loading than in those with intraoperative loading of tramadol.

CONCLUSION

Administering the loading dose of tramadol during surgery decreases the nausea/vomiting associated with high dose of tramadol and improves the quality of tramadol PCA in the relief of postoperative pain.

Is total knee replacement more painful than total hip replacement?

BACKGROUND

During its use in pain management the patient-controlled analgesia (PCA) devices are capable of registering the course of treatment at patient request, the condition of drug delivery and total amount of drug being given. The patients could determine the need of medication to their own satisfaction while forced treatment by the bias of the health care personnel is avoided and the safety of patients is further warranted. In pain relief with this device, the number of requests for analgesia and the dose of analgesic used can be easily measured. Therefore, it is more objective to compare the pain intensity among different types of operation when PCA device is used. Using PCA morphine consumption as a parameter, we attempted to elucidate the difference of intensity of pain associated with total hip and total knee replacements by comparing their morphine requirement.

METHODS

In this prospective cohort study, 50 patients who underwent either total hip replacement (THR, n = 24) or total knee replacement (TKR, n = 26) were enrolled. After recovery from general anesthesia when the patients first complained intense pain in the recovery room, morphine was given intravenously in titration with a calculated loading dose in 30 min to achieve an acceptable analgesia (VAS < or = 3) followed by morphine PCA at 1 mg bolus with a lockout interval of 6 min. The patients were then followed for 48 h. During and at the end of the course the data relevant to pain score, total dose, demand, delivery, and adverse effects were recorded for assessment.

RESULTS

With the use of PCA, the pain scores were similar in both surgical groups in the 48 h observation. Total consumption of morphine in THR was 13.2 +/- 8.1 mg as against 19.7 +/- 5.7 mg in TKR in postoperative day 1 and 25.2 +/- 12.7 mg as against 34.1 +/- 13.9 mg in postoperative day 2 (P < 0.05, t-test). Demand/delivery ratio was not statistically significant between the 2 groups at 24 and 48 h (t-test). Minor adverse effects were seen in both groups but the differences were not significant.

CONCLUSIONS

Using PCA morphine consumption as parameter, we can distinguish the magnitude of pain intensity between 2 major orthopedic surgeries. The deeper and more extensive operation would in total hip replacement does not mean that it is a more painful procedure than total knee replacement. Several speculations are proposed.

The effects of tramadol versus fentanyl in attenuating hemodynamic response following tracheal intubation

BACKGROUND

Tramadol is a novel central acting analgesic. It has been used as a complement to general anesthesia and an effective agent for postoperative analgesia. However, the influence of tramadol on the hemodynamic response following laryngoscopy and tracheal intubation is less known.

METHODS

Forty patients of both sexes, 16-50 year old, ASA physical status I or II, scheduled for elective surgery were randomly divided into equal groups in this prospective, double blind study. After obtaining the baseline data, the patient was given 3 micrograms/kg fentanyl (Group F) or 3 mg/kg tramadol (Group T). Then induction of anesthesia in a uniform and standardized manner was carried out by an anesthesiologist who was blind to the medication. The hemodynamic parameters were measured and recorded immediately after induction but prior to laryngoscopy, 3, 6, and 9 min after intubation, and before incision. We also observed any unusual effect in the postoperative care unit. Chi-square test, Student's t-test and paired t-test were used for statistical comparison. A P less than 0.05 was considered statistically significant.

RESULTS

All patients had a successful induction and intubation. Differences in baseline values were not significant, nor were the differences in the values following induction. After laryngoscopy and intubation, heart rate increased significantly above the baseline level in both groups. The increase of heart rate was significantly more at 6 and 9 min (P < 0.05) and lasted longer in the tramadol group. After intubation, systolic, mean and diastolic arterial pressure (SAP, MAP, DAP) increased significantly above baseline in both groups too, except for DAP in fentanyl group. At 6 and 9 min, the MAP and DAP were significantly higher in tramadol than in fentanyl group (P < 0.05). Six patients in tramadol group had mild pain on injection of tramadol.

CONCLUSIONS

When administered right before thiopental induction, 3 mg/kg tramadol did not display a better attenuation against the increase of hemodynamic profiles than did 3 micrograms/kg fentanyl following tracheal intubation.

Comparison of patient-controlled analgesia (PCA) with tramadol or morphine

PURPOSE

To compared the clinical efficacy of tramadol and morphine using a patient-controlled analgesia (PCA) delivery system.

METHODS

In a prospective, randomized, double blind study, we evaluated 80 adult patients scheduled for elective hip or knee arthroplasty with general inhalational anesthesia. When patients complained of pain in the recovery room, patients were randomized to receive either tramadol or morphine by titration in 30 min to achieve analgesia (VAS < or =4). Equivalent volumes containing either 30 mg x ml(-1) tramadol or 1 mg x ml(-1) morphine were used for PCA with a lockout interval of 10 min. The patients were followed six-hourly for 48 hr for VAS, satisfaction rate, analgesic dose, and side effects.

RESULTS

Patients obtained adequate analgesia with either drug. More patients had very good satisfaction scores in the morphine group in the recovery room (43% vs. 23%, P<0.05) and at 24 hr (40% vs. 20%, P<0.05) than those in the tramadol group. More nausea was evident in the tramadol group (48% vs. 11% in recovery room and 28% vs. 12% in 24 hr, P<0.05) than in the morphine group. Vomiting was also more (28% vs. 5% in recovery room, 15% vs. 3% in 24 hr, P<0.05). Morphine produced more sleepiness (45% vs. 23% in recovery room, P<0.05 and 35% vs. 15% in 24 hr, P<0.05).

CONCLUSION

Tramadol PCA can provide effective analgesia following major orthopedic surgery provided sufficiently high doses are given for loading and by patient demand. However, the incidence of nausea/vomiting is also higher causing decreased satisfaction.

Acute jaundice in pregnancy: acute fatty liver or acute viral hepatitis?

In this case, the difficulty in differential diagnosis between acute viral hepatitis and acute fatty liver of pregnancy was analyzed. These 2 conditions often raise controversal question regarding the decision making on emergency anesthesia for cesarean section to avert complications and optimize management. The dilemma in which an anesthesiologist is put is whether to promise the anesthesia straightaway in the face of a demonstrable acute jaundice in pregnancy to advise a postponement of surgery until a turn for the better. In this embarrassing situation, the authors suggest that a postpronement of surgery is rational to observe the development during which both the mother and the fetus should be closely monitored. Once the necessity of a cesarean section outweighs the benefit of transitional conservative treatment, it should be performed immediately.

Epidural catheter placement in the rabbit--a novel approach

BACKGROUND

Using a pediatric epidural set and through caudal approach, we studied a relatively non-invasive technique for epidural percutaneous cannulation in rabbit for chronic laboratory investigations.

METHODS

Ten rabbits weighing over 3 kg were chosen and anesthetized with intravenous pentothal. A #19 pediatric Touhy needle and 23-gauge catheter were used for cannulation. Via the caudal approach, the epidural space could be located either by a "give" or with a technique of loss of resistance. Under fluoroscopy the catheter was tested with the injection of contrast medium for the confirmation of the proper position. The catheter was then tunneled under the skin and secured. The rabbits were kept in standard care for 4 weeks and then sacrificed by intraperitoneal pentothal overdose. A pathologist blinded to the study carefully examined the whole spine by laminectomy from cervical to coccyx and the findings were recorded.

RESULTS

With the injection of contrast medium, the final position of the catheter was validated by fluoroscopy in all rabbits. Two rabbits sustained immediate complications from the contrast medium and/or technique, of which one died shortly after the contrast medium injection and the other had weakness of the hind legs for a week. At sacrifice, all the catheters were found in good position. Two had hematoma associated with signs of trauma. One developed subcutaneous abscess. One had stitch infection of skin.

CONCLUSIONS

Percutaneous cannulation of epidural catheter is possible in the rabbit. Complications could be ameliorated by prudent approach in a skillful hand. It can be a reasonable model for the study of centrally administered medicines and their neurotoxicity.

The peripheral analgesic effect of tramadol in reducing propofol injection pain: a comparison with lidocaine

BACKGROUND AND OBJECTIVES

Tramadol and metoclopramide have a local anesthetic effect similar to lidocaine following intradermal injection. When metoclopramide was retained in the venous system for 1 minute, it was found to be as effective as lidocaine in reducing propofol injection pain. Using this metoclopramide model, the effects of tramadol in reducing pain on propofol injection was investigated.

METHODS

One hundred five patients were randomly allocated to receive 50 mg tramadol (group T), 60 mg lidocaine (group L), or normal saline (group NS) as pretreatment to reduce pain on propofol injection. Following venous occlusion with a tourniquet (70 mm Hg), one of the drugs was intravenously administered. Venous retention of the drug was maintained for 1 minute. Immediately after the tourniquet release, intravenous injection of 100 mg propofol (10 mL) at a rate of 0.5 mL/s followed. Pain assessment was made after each injection.

RESULTS

Transient minor injection pain and local skin reactions were significantly greater with tramadol than with lidocaine (P < .05). Both tramadol and lidocaine significantly reduced the incidence and intensity of propofol injection pain when compared with normal saline (P < .05).

CONCLUSIONS

Using -minute retention in veins, both tramadol and lidocaine significantly reduced propofol injection pain. A local anesthetic activity is postulated.

Selective lumbar spinal nerve block, a review

Selective spinal nerve block is a useful tool in today's multidisciplinary approach to the diagnosis and treatment of low back pain. The indications, sources of spinal pain, block technique, result interpretation, complications and clinical applications relevant to the subject are discussed. The value of a spinal nerve block relies on an understanding of the pain elements in the back, nerve innervations and careful patient selection. If the technique is performed properly and the results are interpreted cautiously, selective spinal nerve block may prove helpful, especially for patients from whom diagnostic information is inadequate. In some cases, therapeutic effect including that from surgical intervention can be achieved selectively at the symptomatic root. However, controversy remains and therefore well designed clinical studies are needed to provide more information about the validity of this diagnostic and therapeutic modality.

Pain on injection of propofol: the mitigating influence of metoclopramide using different techniques

BACKGROUND

Metoclopramide administered intravenously (i.v.) immediately before injection of propofol, after mixing with propofol, or after a rubber tourniquet for 1 min before propofol injection will reduce pain induced by propofol injection. In this study, these three different techniques in reducing propofol injection pain with metoclopramide were compared with lidocaine or saline to evaluate the most effective method in reducing propofol injection pain.

METHODS

In a randomized, semi-double-blind treatment, 175 patients were included into this study. Patients in group A were pretreated with metoclopramide 10 mg i.v. before propofol (2 mg/kg) induction. Patients in group B were induced with a mixture of propofol and metoclopramide. Patients in group C were pretreated with metoclopramide i.v. with a rubber tourniquet on the arm for 1 min followed by propofol administration. Groups D and E were identical to group C except for the replacement of pretreatment with either lidocaine (40 mg) or saline, respectively.

RESULTS

Groups A, C and D (with active pain prophylaxis) showed a significantly less incidence of pain than the saline control group (E) as propofol was injected. There was no significance difference between metoclopramide and lidocaine in reducing propofol injection pain using a tourniquet technique. The intensity of the propofol injection pain (verbal pain score) was stronger with saline as compared with the other groups.

CONCLUSIONS

We conclude that i.v. retention of metoclopramide with tourniquet is as good as lidocaine and may be a useful alternative for reducing pain on propofol injection.

An alternative continuous caudal block with caudad catheterization via lower lumbar interspace in adult patients

BACKGROUND

Continuous caudal block with caudad catheterization has not yet been mentioned in literatures. We designed a preliminary study to investigate the feasibleness of this technique, spread of contrast medium under fluoroscopy, and its clinical effectiveness.

METHODS

Ten patients were subjected to epidural block (caudal) for elective anal or vaginal procedures. The entry of the epidural needle was made at the L4-5 interspace either with midline or paramedian approach. Through an 18 G Touhy needle with its bevel facing caudally an epidural catheter was threaded until a length of 10 cm was beyond the point of entry. The presence or absence of paresthesia during the passage of catheter and the ease with which the catheter was inserted were recorded. After the procedure, the course on which the catheter traversed and the spread of the medicinal substance in the epidural space were visualized and studied fluoroscopically using 1 and 3 ml iohexol (omnipaque 300 mg/ml) as contrast medium respectively. Then the patients were brought to operating rooms for anesthesia and surgery. Sensory anesthetic level and motor blockade were evaluated fifteen min after 11-15 ml of 2% lidocaine had been injected through the epidural catheter. During anesthesia vital signs were closely monitored, and adverse reaction if any was evaluated and managed.

RESULTS

The insertion of the epidural catheter was considered easy and caused no paresthesia in nine patients. Catheter insertion encountered moderate resistance and induced paresthesia in one patient. Yet, the catheter was advanced successfully to the expected length. In radiological study with contrast medium, the course of the epidural catheter was not always traceable, while the spread of the contrast medium was clearly identified. Epidural spread occurred in eight patients, left paravertebral spread in one patient, and right retrorectal spread in another one patient. As to clinical assessment, adequate sensory blockade with local anesthetic was gained in 8 patients with well-preserved motor function of the lower limbs. In one patient the caudal block worked well after the withdrawal of the catheter 5 cm in length. Spinal anesthesia was supplemented in one patient due to failure of the caudal block.

CONCLUSIONS

Continuous caudal block with caudawise catheterization via lower lumbar interspaces is feasible (eight of 10 patients in this study) with respect to technique and clinical effect. Paravertebral and retrorectal migrations of the catheter may occur in spite of smooth catheterization. Either migration might lead to a failure of caudal block.

Local anesthetic effect of tramadol, metoclopramide, and lidocaine following intradermal injection

BACKGROUND AND OBJECTIVES

We observed clinically that tramadol and metoclopramide appear to have local anesthetic action. Tramadol is a central-acting analgesic. Metoclopramide is a commonly used antiemetic. The local anesthetic effect of tramadol in reducing propofol injection pain has never been mentioned, although it was speculated with metoclopramide.

METHODS

We conducted a double-blind, placebo-controlled study by injecting tramadol or metoclopramide intradermally in 10 healthy volunteers (5 men, 5 women; age 25-56 years). Each subject received 0.5 mL of four solutions in random order on the volar side of the forearm. These solutions were 25 mg tramadol, 5 mg metoclopramide, 5 mg lidocaine, and 0.5 mL normal saline. Pain on injections and the degree of local anesthesia (tested by pinprick, light touch, and cold) at each site was reported on a 0-3 scale at designed time intervals.

RESULTS

Like 1% lidocaine, tramadol and metoclopramide demonstrated loss of sensation for pinprick, light touch, and cold for 15 minutes after intradermal injection (P < .01 ).

CONCLUSIONS

Intradermal tramadol or metoclopramide can produce local anesthetic effect.

Intradermal injection of tramadol has local anesthetic effect: a comparison with lidocaine

BACKGROUND

We observed that intravenous retention of tramadol with a pneumatic tourniquet on the arm inflated to 70 mmHg for one minute could effectively reduce the subsequent propofol injection pain. Tramadol is a central-acting analgesic. The local analgesic effect of tramadol on reducing propofol injection pain is not well known.

METHODS

To explore this problem we conducted a double-blind study on intradermal injections of tramadol 25 mg, lidocaine 5 mg and normal saline (all in 0.5 ml volume) which were given to each of the 10 healthy volunteers on the forearm at random. Pain on injections and the degree of local analgesia to pinprick, light touch and cold at each injection site were scored on a 0-4 scale at designated intervals.

RESULTS

5% tramadol, similar to 1% lidocaine, rendered loss of sensation to pin prick, light touch and cold for 30 min after intradermal injection as compared with normal saline (p < 0.01).

CONCLUSIONS

We concluded that intradermal injection of tramadol or lidocaine can produce local anesthetic effect.

Negative pressure pulmonary oedema induced by direct suctioning of endotracheal tube adapter

PURPOSE

Negative pressure pulmonary oedema (NPPE) is a well-recognized but rare complication secondary to upper airway obstruction such as laryngeal spasm during emergence from general anaesthesia. Cauterization of the second and third thoracic sympathetic ganglia is a treatment for hyperhidrosis of the hands. We report a case of NPPE induced by direct suctioning of the endotracheal tube adapter during thoracic sympathetic ganglionectomy without recognized upper airway obstruction.

CLINICAL FEATURES

A 19-yr-old otherwise healthy, non-smoking man was scheduled for elective bilateral chest endoscopic ablation of the second and third thoracic sympathetic ganglion for hyperhidrosis of the hands under general anaesthesia. To view and cauterize the ganglion with the endoscope, the surgeon requested cessation of positive pressure ventilation. As the surgeon could not satisfactorily visualize the target ganglia, he requested brief application of wall suction via the ETT tube adapter. A pressure of -100 mmHg was generated which lasted for three to four seconds. The goal was to reduce further the lung volume by increasing the pneumothorax produced by the endoscope. The patient developed negative pressure pulmonary oedema without upper airway obstruction.

CONCLUSION

This case demonstrated that intrathoracic negative pressure generated by direct ETT adapter suctioning may produce pulmonary oedema similar to that induced by laryngeal spasm during the emergence of general anaesthesia.

Application of spinal pain mapping in the diagnosis of low back pain--analysis of 104 cases

BACKGROUND

Low back pain is probably the most common pain problem seen in a general pain clinic and the cause of low back pain can be enigmatic at times. Often the pain sources are difficult to identify with the conventional diagnostic modalities. Spinal pain mapping is a sequence of well organized nerve block procedures. We undertook this study to evaluate the usefulness of this modality in diagnosing low back pain of uncertain etiology.

METHODS

In this prospective study, 104 consecutive adult patients who underwent spinal pain mapping were examined and analyzed. All patients had intractable low back pain of undetermined etiology after medical history, physical examination and 4-view roentgenographic evaluation of the lumbar spine had been undertaken to locate it. In addition, 41 patients (39%) had one or more of the following tests done, which included CT, MRI, EMG/NC but all failed to delineate the causes of the pain. All patients failed to respond to the conservative therapies.

RESULTS

With pain mapping the source of pain was found to be caused by sacro-iliac joint in 6%, lumbar nerve root in 20%, facet joint in 24%, combined lumbar nerve root and facet disease in 24%, internal disc disorder in 7%, combined facet and sacro-iliac joint in 4% and lumbar sympathetic dystrophy in 2% of patients. Pain mapping failed to demonstrate the causes of the pain in the remaining 13% of the patients.

CONCLUSIONS

Considering the difficult nature of this group of patients, spinal pain mapping provided a useful functional approach to the diagnosis of low back pain with obscure etiology in 87% of patients in our series.

The peripheral analgesic effect of meperidine in reducing propofol injection pain is not naloxone-reversible

BACKGROUND AND OBJECTIVES

Meperidine is frequently used in general anesthesia and perioperative analgesia. In addition to its opioid action, meperidine possesses some local anesthetic properties. A preliminary study using the tourniquet venous retention technique found meperidine to be more effective in reducing propofol injection pain than fentanyl or morphine, both of which were slightly better than placebo. This study was undertaken to evaluate whether this peripheral analgesic effect of meperidine is affected by naloxone.

METHODS

In a randomized, double-blind manner, after venous occlusion with a tourniquet, meperidine 40 mg was given intravenously to patients in group A (n = 31), meperidine 40 mg followed by naloxone 0.04 mg to group B (n = 32), meperidine 40 mg followed by naloxone 0.2 mg to group C (n = 30), and normal saline placebo to group D (n = 30). The venous retention of drug(s) was maintained for 1 minute, followed by tourniquet release and intravenous administration of propofol 100 mg. Pain assessment was made immediately after the propofol injection.

RESULTS

All three groups given meperidine had significantly less propofol injection pain (P < .01 ) than the group given saline placebo, and there was no difference among groups A, B, and C.

CONCLUSION

The peripheral analgesic effect of meperidine in reducing propofol injection pain is not mediated by its opioid activity.

The analgesic effect of fentanyl, morphine, meperidine, and lidocaine in the peripheral veins: a comparative study

Using venous retention with a tourniquet (70 mm Hg), we performed a randomized, double-blind study to assess the efficacy of I.V. pretreatment with fentanyl, morphine, meperidine, or lidocaine in reducing propofol injection pain. Immediately after venous occlusion with a tourniquet, I.V. fentanyl 150 microg (Group A, n = 35), morphine 4 mg (Group B, n = 35), meperidine 40 mg (Group C, n = 35), 2% lidocaine 3 mL (Group D, n = 35), or normal saline 3 mL (Group E, n = 35; as placebo control) was given to adult patients. The venous retention of the drug was maintained for 1 min, followed by tourniquet release and I.V. administration of propofol 100 mg. Pain assessment was made immediately after the propofol injection. Lidocaine and meperidine significantly reduced propofol injection pain more than placebo (P < 0.05), but there were more side effects in the meperidine group. Fentanyl and morphine reduced the intensity of propofol injection pain (P < 0.05) and had some effect in reducing the incidence of propofol injection pain, but the difference did not reach statistical significance. The order of efficacy was lidocaine approximately meperidine > morphine approximately fentanyl. We postulate that the peripheral analgesic effect of these opioid is due to their local anesthetic activity.

IMPLICATIONS

Propofol, a commonly used anesthetic, often causes pain on injection. Given as venous retention pretreatments 1 min before propofol, meperidine and lidocaine were found to significantly reduce the propofol injection pain, whereas fentanyl and morphine only slightly reduced the propofol injection pain.

Comparison of intravenous retention of fentanyl and lidocaine on local analgesia in propofol injection pain

BACKGROUND

With a tourniquet on arm for arresting venous blood flow, we evaluated the efficacy of intravenous (i.v.) retention of fentanyl and lidocaine in reducing the pain on i.v. propofol injection during general anesthesia.

METHODS

One hundred and twelve patients were studied. Following a venous occlusion by a tourniquet inflated to 70 mmHg, patients in Group A (n = 38) received normal saline (NS) 3 ml, while those in Group B (n = 37) and in Group C (n = 37) respectively received fentanyl 150 micrograms or 3 ml and 2% lidocaine 3 ml (60 mg). The venous retention of drug was maintained for 1 min, followed immediately by tourniquet release and propofol 100 mg i.v. injection over 20 s.

RESULTS

Both fentanyl and lidocaine treatments (Groups B and C) were significantly better than placebo (Group A) in reducing pain on propofol injection (p < 0.005). Lidocaine 60 mg was more effective than fentanyl 150 micrograms in reduction of pain associated with i.v. propofol (p < 0.001). Injection of fentanyl itself caused pain in 28% of patients as compared to 2% in the lidocaine group. Mild local skin erythema was noted in 14% of patients with fentanyl venous retention versus 0% of patients with lidocaine venous retention.

CONCLUSIONS

Intravenous retention of fentanyl 150 micrograms, although less effective than that of lidocaine (p < 0.001), showed local analgesic effect in reducing the pain on propofol injection. The hypothetic mechanisms of action were speculated.