Peribulbar and retrobulbar anesthesia with prilocaine: a comparison of two methods of local ocular anesthesia

Prilocaine (Citanest) has been shown to be a satisfactory alternative to lignocaine, with certain important advantages, including superior diffusion. The latter may be especially important in peribulbar anesthesia, where the level of diffusion is a critical factor in providing a timely, high-quality block. In a prospective randomized study, we compared the effectiveness of peribulbar vs retrobulbar administration of prilocaine. Eighty-seven patients undergoing elective intraocular surgery were randomized to receive either retrobulbar or peribulbar anesthesia with prilocaine 3% with felypressin and hyaluronidase. Pain of injection, akinesia, and anesthesia were evaluated at predetermined intervals after injection. Except for the fact that lid akinesia occurred earlier in the peribulbar group, there was no difference in the quality or rate of onset of overall akinesia in the two groups. Nor were there any differences in the pain associated with injection. Both groups had excellent operative anesthesia and akinesia.     

Incidence of transient neurologic symptoms after hyperbaric subarachnoid anesthesia with 5% lidocaine and 5% prilocaine

Laparoscopy causes an increase in intraabdominal pressure and may lead to an increase in gastroesophageal reflux (GER). We designed this study to assess and compare the frequency of GER and tracheal contamination in patients undergoing laparoscopic cholecystectomy (LC) and gynecological laparoscopy (LG). We studied 20 LC and 17 LG patients. The pH was measured using monocrystalline antimony pH electrodes positioned in the middle to upper esophagus and on the posterior wall of the trachea distal to the tip of the endotracheal tube. Acid reflux was defined as a decrease in esophageal pH to 4.0 or less. Alkaline reflux was defined as an abrupt increase in esophageal pH of more than 1.0, not associated with previous acid reflux. More than 80% of all patients at baseline had a gastric pH < or = 2. Overall, acid GER alone occurred in 47% patients in the LG group and in 15% patients in the LC group. During recovery, a larger proportion of patients had acid reflux in the LG group (47%) than in the LC group (10%). In contrast, alkaline reflux occurred in 75% of LC patients and 11.7% of LG patients. After cholecystectomy, there is an acute increase in the incidence of alkaline reflux. This alkaline reflux may be due to duodenogastric reflux resulting in an alkaline gastric shift. IMPLICATIONS: We studied the incidence of reflux of stomach contents in patients undergoing laparoscopic (keyhole) surgery for cholecystectomy or gynecology, using pH probes in the esophagus (gullet) and the trachea (windpipe). Acid reflux was very common but did not pass into the trachea. After gallbladder removal, the refluxed material became alkaline.     

EMLA cream and lidocaine local injection in the treatment of extravenous thiopental injection--a case report

PURPOSE: To evaluate the use of 4 Fr radial artery catheters as an alternative to both transbrachial and transfemoral approaches. METHODS: Seventy examinations were performed via the transradial route using 4 Fr 130-cm-long pigtail catheters. Prior to puncture the radial artery was assessed with pulse oximetry to ensure that it did not contribute the dominant blood supply to the hand. Patients were reassessed for complications within 24 hr of the procedure. RESULTS: Acceptable images were obtained in femoral arteriography, arch aortography, and selective carotid studies. In three of six renal arteriograms, images were suboptimal. There was a total technical failure rate of 5.7%. Significant complications were encountered in 4.3%, but no hand ischemia occurred. CONCLUSION: The transradial route for arteriography is easy to learn and has a low complication rate. It is a reasonable alternative approach to transfemoral arteriography for true outpatient peripheral angiography and in cases where the transfemoral route is not feasible, though it did not prove satisfactory for renal arteriography in hypertensive patients.     

Comparison of lidocaine and saline for epidural top-up during combined spinal-epidural anesthesia in volunteers

This study was designed to determine the efficacy of saline as an epidural top-up to prolong spinal anesthesia during combined spinal-epidural anesthesia (CSEA). Eight volunteers received three separate CSEAs with intrathecal lidocaine (50 mg). After two-segment regression, each subject received either a saline (10 mL), lidocaine 1.5% (10 mL), or control sham (0.5 mL saline) epidural injection in a randomized, double-blind, triple cross-over fashion. Sensory block was assessed by pinprick and tolerance to transcutaneous electrical stimulation (TES) equivalent to surgical stimulation at the knee and ankle. Motor strength was assessed with iso-metric force dynamometry. Data were analyzed with a repeated measures analysis of variance and a paired t-test. Sensory block to pinprick was prolonged in the thoracolumbar dermatomes only by lidocaine (P < 0.05). Neither lidocaine nor saline prolonged the duration of tolerance to TES at the tested sites. Instead, saline decreased the duration of tolerance to TES by 20 and 24 min at the knee and ankle (P < 0.05). Recovery from motor block at the quadriceps was prolonged by an epidural injection of lidocaine (P < 0.05). We conclude that when 10 mL of epidural saline is administered after two-segment regression, it is an ineffective top-up and may decrease the duration of spinal anesthesia during CSEA.     

Efficacy and tolerance of a local application of phenazone and chlorhydrate lidocaine (Otipax) in infants and children with congestive otitis

The efficacy and safety of ear drops containing phenazone and lidocaine hydrochloride (Otipax) for the treatment of congestive myringitis were evaluated in 18 infants and children aged 1 to 10 years. Relief of pain was evident 5 minutes after instillation and significant after 15 to 30 minutes. Serial photographs of the tympanic membrane demonstrated prompt improvement of inflammation. Congestion was significantly reduced after five minutes and overall ear drum color was significantly improved after 15 to 30 minutes. No adverse effects were recorded. These data suggest that Otipax is effective and safe for the treatment of painful congestive myringitis in infants and children.     

Tumescent anesthesia with a lidocaine dose of 55 mg/kg is safe for liposuction

BACKGROUND: The safe upper limit of lidocaine dosage in tumescent anesthesia for liposuction has been reported to be 35 mg/kg. OBJECTIVE: This study was undertaken to: 1) evaluate the safety of tumescent anesthesia in liposuction when lidocaine doses greater than 35 mg/kg are required, 2) determine the time interval when the peak plasma lidocaine level occurs following administration of tumescent anesthesia, and 3) assess if the safety of large volume tumescent anesthesia is due to significant lidocaine removed by liposuction. METHODS: Sixty patients who underwent liposuction with a mean lidocaine dose of 57 mg/kg were prospectively evaluated for development of any signs or symptoms of lidocaine toxicity by multiple interviews over a 24-hour period. In addition, another 10 patients who received a mean lidocaine dose of 55 mg/kg had serial plasma lidocaine level measurements over a 24-hour period following liposuction. The lidocaine level of the aspirate was also measured to assess any significant lidocaine removed by liposuction. RESULTS: No evidence of lidocaine toxicity was found based on subjective evaluation of 60 patients as well as determined by plasma sampling of 10 patients. The peak plasma lidocaine concentration occurred at approximately 4 or 8 hours after infusion of tumescent anesthesia. The 24-hour plasma lidocaine level suggests that residual lidocaine is present in the subcutaneous tissue allowing for postoperative analgesia beyond this time. A negligible amount of lidocaine was removed by liposuction as determined by the lidocaine level of the aspirate. CONCLUSION: This study suggests that tumescent anesthesia with a total lidocaine dose of up to 55 mg/kg is safe for use in liposuction.     

Electrochemical properties of a lithium-potassium chloride molten eutectic mixture held in contact with neodymium and dysprosium

The dependence of the reaction capacity (R) of the lithium-potassium chloride molten eutectic mixture held in contact with neodymium and dysprosium on the content of the ions of the corresponding rare earth metal (REM) is investigated at 773, 873, and 973 K. The data on the values of R made it possible to evaluate the magnitude of charges of the Nd and Dy ions transferring into the melt during the corrosion of studied REMs and concretize the mechanism of their no-current transfer to more electropositive metals (by the example of nickel).     

Intravenously administered ketamine HCl and diazepam for anesthesia of raptors

A combination of ketamine HCl and diazepam given intravenously was successfully utilized to induce anesthesia for various surgical procedures in 40 raptors. A dosage of 30 to 40 mg of ketamine HCl/kg of body weight and 1.0 to 1.5 mg of diazepam/kg of body weight was satisfactory for diurnal raptors. Owls were more sensitive to the anesthetic combination, necessitating greater care in anesthetizing them. Abundant body fat was found to be an important factor in calculation of the proper dose of this combination.     

Prevention of contamination with a heat-and-moisture-exchanger (HME) and bacterial filter during clinical anesthesia

Although the use of HME and bacterial filter is a common practice to protect the anesthesia machine as well as the patients from bacterial contaminants, there is no report demonstrating the effectiveness of this filter in clinical anesthesia setting. We evaluated the actual effectiveness of the filter during clinical use. While the anesthesia breathing circuit, two bacterial filters (BB 50 T, Nihon PALL) and anesthesia bag, which were sterilized with ethylen oxide gas (EOG), were connected to the anesthesia machine and used continuously for one week, EOG sterilized HME and bacterial filter (BB 25 A, Nihon PALL) were changed before each anesthesia. Culture samples were taken from the BB 25 A, the breathing circuit and the machine side of the BB 50 T. Of the 117 BB 25 A samples taken, 6 were positive for Micrococcus, alpha-Streptococcus, Bacillus, and Staphylococcus epidermidis. From 21 breathing circuit "internal" samples, one was positive for Bacillus, Staphylococcus epidermidis. But the contamination from outside sources was suspected, since all the BB 25 as used with this circuit were negative. Use of BB 25 A prevents contamination of the breathing circuit for a period of one week. If we use BB 25 A in every anesthesia case, the changing of the breathing circuit is unnecessary, reducing the cost and simplifying procedures during clinical practice.     

Althesin (alphadione, CT 1341) a 'new' induction agent for anesthesia

Althesin (alphadione) is a hypnotic agent introduced in the U.K. a few years ago by the firm of Glaxo. It is mixture of two steroids: alphaxalone 9 mg per ml and alphadolone 3 mg per ml, in solution in cremophore EL. After a concise review of the history of steroid anesthetics, the pharmacology of the new product is described. In a personal investigation, Althesin was used to induce anesthesia in 100 patients. The dose equivalent with thiopentone was determined first. It was found to amount to 52 microliter per kg corresponding to 3 mg per kg of thiopentone. A separate form was completed for each individual patient, to record the side effects, if any. The pulse and blood pressure were checked once a minute after the induction (for 5 minutes). In 8 patients the following parameters were recorded: plethysmogram, ECG, central venous pressure, pulse rhythm arterial pressure, stroke volume and cardiac output. Compared with thiopentone, Althesin is not significantly worse, but neither does it present any advantages where the circulatory parameters determined are concerned. In view of this and the recent publication concerning hypersensitivity reactions, we have ceased to use this hypnotic agent in our department.     

Comparison of survival of diarrhoeagenic agents in two local weaning foods (ogi and koko)

The pH values of both cooked and uncooked ogi and koko samples were determined and the survival rate of four diarrhoeagenic agents, enteroinvasive Escherichia coli, Salmonella typhi, Shigella flexneri, and Vibrio cholerae were studied after they were seeded into cooked ogi and koko. Analysis of the pH of the cooked inoculated samples showed that there was a slight increase in pH (decrease in acidity) during storage for 48 h and 37 degrees C (from 3.5 to 3.7 for ogi and from 3.7 to 4.1 for koko). The study also showed that ogi had a slightly lower pH value than koko both before and after cooking. In both cases, the cooked samples had a slightly lower pH value than the uncooked samples. The pH value of ogi ranged from 3.0 to 3.6 and that of koko from 3.5 to 3.9. The survival experiment showed that the inoculated enteric pathogens were inhibited in cooked ogi and koko during storage for 24-48 h. The antibacterial effect of cooked koko was more pronounced, on the four enteric pathogens studied, than that of cooked ogi. Except for Shigella flexneri and E. coli in ogi, non of the other bacteria studied was recovered after 24 h.     

Surface-induced mild hypothermia anesthesia for hepatectomy in a patient with a giant hemangioma of the liver (Kasabach-Merritt syndrome)

A 63-year-old woman presenting with thrombocytepenia and signs of intravascular coagulation (prothronbin time, 59%: FDP, 100 micrograms.ml-1) due to a giant hemangioma of the liver (Kasabach-Merritt syndrome) was scheduled for the resection of the right lobe of the liver. In order to protect the liver on occlusion of the right hepatic artery and portal vein, we induced mild hypothermia technique with vasodilation and surface cooling by convecting warming device together with hepatoprotective agents of PGE1 and ulinastatin. Severe, acute massive bleeding occurred due to the injury of the middle hepatic vein and from the resected surface of the liver. Her rectal temperature was 31.9 degrees C during massive bleeding. Her hemoglobin decreased to 3.9 g.dl-1. Total estimated blood loss was 22,000 ml. The weight of the resected liver was 2.5 kg. The maximum postoperative levels of T-Bil and GOT were 2.47 mg.dl-1 and 171 IU.l-1, respectively. The liver seemed to have been well preserved and no other complications were observed. The hemangioma was completely removed by excision of the right lobe of the liver. Subsequently, all coagulation parameters returned to normal, indicating a complete reversibility of the coagulopathy. Surface-induced mild hypothermia is a useful and valuable method for protecting the liver during severe massive bleeding.     

The partition coefficient as a predictor of local anesthetic potency for spinal anesthesia: evaluation of five local anesthetics in a mouse model

Local anesthetic partition coefficients correlate with drug potencies in vitro, but in vivo data have not always complimented in vitro results. Despite extensive studies on intrathecal anesthetic action, whether there is correlation between the partition coefficient and local anesthetic potency has not been addressed. Mice (n = 150) were randomly allocated into 15 groups. Intrathecal injections of etidocaine (E), tetracaine (T), bupivacaine (B), lidocaine (L), or procaine (P) were administered and analgetic effect was measured using tail-flick (TF) test. Concentration-response regressions were constructed for each drug; EC50 values were calculated and compared at 95% confidence intervals. The EC50 values between E (0.017%), T (0.019%), and B (0.012%) were not significantly variant. The EC50 of L (0.098%) and P (0.229%) were significantly different from each other and from E, T, and B. The EC50 values were converted to ED50 in nmols. Relative anesthetic potency, defined as the inverse value of ED50 of drug was 23:16:15:2.4:1 for B, E, T, L, and P, respectively. ED50 showed high correlation (R = 0.978) with partition coefficients of local anesthetics. This study implies that the partition coefficient is a predictor of intrathecal local anesthetic potency. We suggest that the mouse model is reliable for evaluation of intrathecal local anesthetic action.     

Comparison of tramadol and tramadol/droperidol mixture for patient-controlled analgesia

PURPOSE: To compare the analgesic efficacy and side effects of tramadol vs tramadol and droperidol for post-operative patient-controlled analgesia (PCA). METHODS: Randomised, double-blind study. Thirty-four patients undergoing elective colorectal or head and neck surgery were allocated to Group 1 (n = 18, PCA bolus 10 mg tramadol) or Group 2 (n = 16, PCA bolus 10 mg tramadol + 0.1 mg droperidol). Anaesthesia was induced with fentanyl and thiopentone and maintained with O2, N2O plus enflurane or isoflurane with iv morphine at doses decided by the attending anaesthetists. Muscle relaxation was achieved with atracurium or vecuronium. Patients were observed four-hourly for pain using an 11-point verbal rating scale (VRS). Nausea and vomiting, and sedation were assessed using four-point scales post-operatively. Vital signs, request for rescue anti-emetic and analgesic, and overall satisfaction were recorded. RESULTS: The mean nausea scores were lower in Group 2 (1.00 +/- 1.33 vs 0.06 +/- 0.25 at 0-8 hr, 1.22 +/- 1.93 vs 0.06 +/- 0.25 at 8-16 hr, P < 0.01; 0.81 +/- 1.68 vs 0 at 32-40 hr, P < 0.05; Group 1 vs Group 2). The vomiting scores were also lower (0.50 +/- 1.04 vs 0 at 0-8 hr, 0.67 +/- 1.50 vs 0, at 8-16 hr, P < 0.05; Group 1 vs Group 2). Seven (39%) patients in Group 1, but none in Group 2 requested rescue anti-emetic (P < 0.01). There were no differences in VRS, sedation score, overall satisfaction or vital signs. CONCLUSION: Tramadol and droperidol combination is superior to tramadol alone for post-operative PCA. It provides a similar quality of analgesia with less nausea and vomiting and without an increase in sedation.