Real-time Ultrasound-Guided Lumbar Epidural with Transverse Interlaminar View: Evaluation of an In-Plane Technique.

OBJECTIVE: The anatomical landmarks method is currently the most widely used technique for epidural needle insertion and is faced with multiple difficulties in certain patient populations. Real-time ultrasound guidance has been recently used to aid in epidural needle insertion, with promising results. Our aim was to test the feasibility, success rate, and satisfaction associated with a novel real-time ultrasound-guided lumbar epidural needle insertion in the transverse interlaminar view. DESIGN: Prospective descriptive trial on a novel approach. SETTING: Operating room and preoperative holding area at a tertiary care hospital. SUBJECTS: Adult patients presenting for elective open prostatectomy and planned for surgical epidural anesthesia. METHODS: Consented adult patients aged 30-80 years scheduled for open prostatectomy under epidural anesthesia were enrolled. Exclusion criteria included allergy to local anesthetics, infection at the needle insertion site, coagulopathy, and patient refusal. A curvilinear low-frequency (2-5 MHz) ultrasound probe and echogenic 17-G Tuohy needles were used by one of three attending anesthesiologists. Feasibility of epidural insertion was defined as a 90% success rate within 10 minutes. RESULTS: Twenty-two patients were enrolled into the trial, 14 (63.6%) of whom found the process to be satisfactory or very satisfactory. The median time to perform the block was around 4.5 minutes, with an estimated success rate of 95%. No complications related to the epidural block were observed over the 48 hours after the procedure. CONCLUSIONS: We demonstrate the feasibility of a novel real-time ultrasound-guided epidural with transverse interlaminar view.

Comparison of three techniques for ultrasound-guided femoral nerve catheter insertion: a randomized, blinded trial.

BACKGROUND: Ultrasound guidance for continuous femoral perineural catheters may be supplemented by electrical stimulation through a needle or through a stimulating catheter. The authors tested the primary hypothesis that ultrasound guidance alone is noninferior on both postoperative pain scores and opioid requirement and superior on at least one of the two. Second, the authors compared all interventions on insertion time and incremental cost. METHODS: Patients having knee arthroplasty with femoral nerve catheters were randomly assigned to catheter insertion guided by: (1) ultrasound alone (n = 147); (2) ultrasound and electrical stimulation through the needle (n = 152); or (3) ultrasound and electrical stimulation through both the needle and catheter (n = 138). Noninferiority between any two interventions was defined for pain as not more than 0.5 points worse on a 0 to 10 verbal response scale and for opioid consumption as not more than 25% greater than the mean. RESULTS: The stimulating needle group was significantly noninferior to the stimulating catheter group (difference [95% CI] in mean verbal response scale pain score [stimulating needle vs. stimulating catheter] of -0.16 [-0.61 to 0.29], P < 0.001; percentage difference in mean IV morphine equivalent dose of -5% [-25 to 21%], P = 0.002) and to ultrasound-only group (difference in mean verbal response scale pain score of -0.28 [-0.72 to 0.16], P < 0.001; percentage difference in mean IV morphine equivalent dose of -2% [-22 to 25%], P = 0.006). In addition, the use of ultrasound alone for femoral nerve catheter insertion was faster and cheaper than the other two methods. CONCLUSION: Ultrasound guidance alone without adding either stimulating needle or needle/catheter combination thus seems to be the best approach to femoral perineural catheters.

Effect of perioperative intravenous lidocaine administration on pain, opioid consumption, and quality of life after complex spine surgery.

BACKGROUND: The authors tested the primary hypothesis that perioperative IV lidocaine administration during spine surgery (and in the postanesthesia care unit for no more than 8 h) decreases pain and/or opioid requirements in the initial 48 postoperative hours. Secondary outcomes included major complications, postoperative nausea and vomiting, duration of hospitalization, and quality of life. METHODS: One hundred sixteen adults having complex spine surgery were randomly assigned to perioperative IV lidocaine (2 mg·kg·h) or placebo during surgery and in the postanesthesia care unit. Pain was evaluated with a verbal response scale. Quality of life at 1 and 3 months was assessed using the Acute Short-form (SF) 12 health survey. The authors initially evaluated multivariable bidirectional noninferiority on both outcomes; superiority on either outcome was then evaluated only if noninferiority was established. RESULTS: Lidocaine was significantly superior to placebo on mean verbal response scale pain scores (P < 0.001; adjusted mean [95% CI] of 4.4 [4.2-4.7] and 5.3 [5.0-5.5] points, respectively) and significantly noninferior on mean morphine equivalent dosage (P = 0.011; 55 [36-84] and 74 [49-111] mg, respectively). Postoperative nausea and vomiting and the duration of hospitalization did not differ significantly. Patients given lidocaine had slightly fewer 30-day complications than patients given placebo (odds ratio [95% CI] of 0.91 [0.84-1.00]; P = 0.049). Patients given lidocaine had significantly greater SF-12 physical composite scores than placebo at 1 (38 [31-47] vs. 33 [27-42]; P = 0.002) and 3 (39 [31-49] vs. 34 [28-44]; P = 0.04) months, postoperatively. CONCLUSION: IV lidocaine significantly improves postoperative pain after complex spine surgery.

Continuous femoral nerve blocks: decreasing local anesthetic concentration to minimize quadriceps femoris weakness.

BACKGROUND: Whether decreasing the local anesthetic concentration during a continuous femoral nerve block results in less quadriceps weakness remains unknown. METHODS: Preoperatively, bilateral femoral perineural catheters were inserted in subjects undergoing bilateral knee arthroplasty (n = 36) at a single clinical center. Postoperatively, right-sided catheters were randomly assigned to receive perineural ropivacaine of either 0.1% (basal 12 ml/h; bolus 4 ml) or 0.4% (basal 3 ml/h; bolus 1 ml), with the left catheter receiving the alternative concentration/rate in an observer- and subject-masked fashion. The primary endpoint was the maximum voluntary isometric contraction of the quadriceps femoris muscles the morning of postoperative day 2. Equivalence of treatments would be concluded if the 95% CI for the difference fell within the interval -20%-20%. Secondary endpoints included active knee extension, passive knee flexion, tolerance to cutaneous electrical current applied over the distal quadriceps tendon, dynamic pain scores, opioid requirements, and ropivacaine consumption. RESULTS: Quadriceps maximum voluntary isometric contraction for limbs receiving 0.1% ropivacaine was a mean (SD) of 13 (8) N · m, versus 12 (8) N · m for limbs receiving 0.4% [intrasubject difference of 3 (40) percentage points; 95% CI -10-17; P = 0.63]. Because the 95% CI fell within prespecified tolerances, we conclude that the effect of the two concentrations were equivalent. Similarly, there were no statistically significant differences in secondary endpoints. CONCLUSIONS: For continuous femoral nerve blocks, we found no evidence that local anesthetic concentration and volume influence block characteristics, suggesting that local anesthetic dose (mass) is the primary determinant of perineural infusion effects.

A propensity-matched comparison of the incidence of new-onset postoperative atrial arrhythmias in cardiac and noncardiac thoracic surgery patients.

OBJECTIVE: The primary aim of this investigation was to compare the incidence of new-onset postoperative atrial arrhythmias (POAAs) in cardiac versus noncardiac thoracic surgery patients. A subgroup analysis also was performed in the cardiac surgery patients comparing POAAs in patients who underwent cardiac surgery on and off cardiopulmonary bypass (CPB). DESIGN: This was a retrospective study using the Department of Cardiothoracic Anesthesia patient registry. All patients (n = 33,500) undergoing cardiac (n = 29,057) and noncardiac thoracic (n = 4,443) surgeries between 1993 and 2004 were identified from the patient registry. Two propensity-matched comparisons for the incidence of POAAs were made: (1) in cardiac surgery patients versus noncardiac thoracic surgery patients and (2) in patients undergoing cardiac surgery with versus without CPB. SETTING: A large metropolitan multidisciplinary clinic. PARTICIPANTS: Patients. INTERVENTION: No interventions were done because this was a retrospective study. MEASUREMENTS AND MAIN RESULTS: The cardiac patients had a significantly higher incidence of POAAs when compared with noncardiac thoracic surgery patients (11.6% v 7.5%, p < 0.001). There was no significant difference in the incidence of POAAs between patients undergoing CPB versus off-pump CPB (13.3% v 12.3%, p = 0.3). CONCLUSION: The incidence of new-onset POAAs was higher in patients undergoing cardiac surgery than in patients undergoing noncardiac thoracic surgery in propensity-matched patient groups. CPB was not associated with new-onset POAAs.

An 11-year, single-institution analysis of intra-aortic balloon pump use in cardiac surgery.

OBJECTIVES: The primary objective of this study was to analyze perioperative intra-aortic balloon pump (IABP) insertion in patients undergoing cardiac surgery in the authors' institution from 1995 to 2005 and to propose an explanation for changes in use over this period. A secondary objective was to assess patient variables associated with IABP use. DESIGN: This is a retrospective study including patients who underwent cardiac surgery between 1995 and 2005. SETTING: The Cardiothoracic Anesthesia Patient Registry of a single teaching institution was queried to obtain the required information. PARTICIPANTS: Thirty thousand two hundred sixty-nine cardiac surgery patients. INTERVENTIONS: Intra-aortic balloon pump insertion before surgery, after cardiopulmonary bypass, or in the cardiovascular intensive care unit was assessed in patients who underwent isolated coronary artery bypass graft surgery, valve surgery, or both. Select patient variables were analyzed for their association with IABP insertion. Transesophageal echocardiography (TEE) examinations, milrinone use, and mortality rates also were determined. MEASUREMENTS AND MAIN RESULTS: Among 30,269 cardiac surgery patients, 1,310 (4.32%) underwent IABP insertion. Combined preoperative, intraoperative, and postoperative IABP use decreased from 7.8% in 1995 to 3.0% in 2005. Simultaneously, the intraoperative use of milrinone increased from 4.8% to 8.8% and postoperative use increased from 5.2% to 7.8%. The number of intraoperative TEE examinations more than doubled from approximately 1,700 to 3,500. The overall mortality for patients with preoperative, intraoperative, and postoperative IABP insertion was 12.6%, 17.5%, and 47.7%, respectively. CONCLUSIONS: From 1995 to 2005, preoperative, intraoperative, and postoperative IABP use decreased by approximately 60% in cardiac surgery patients. Simultaneously, the use of TEE and milrinone each doubled. Although a cause-effect relationship cannot be established from the present study's observational data, the trends coincide and may be related.

Overdrive pacing for endovascular repair of an aortic arch aneurysm.

The endovascular treatment of aortic arch aneurysms is a relatively new technique and is associated with significant surgical and anesthetic challenges. We report a case of a 77-year-old patient with an aortic arch aneurysm at the level of the isthmus, measuring 4.9 x 6.5 cm. The aneurysm involved the origin of the left subclavian and vertebral arteries. The arch was of the bovine type and the left vertebral artery came directly off the aorta. The patient underwent an uneventful open left carotid-to-subclavian bypass several days before the aortic repair. During the endovascular surgery, a stent-graft was deployed just distal to the innominate trunk. Endoleak was noted at the inferior aspect of the stent-graft, which failed to seal with placement of an extension stent-graft. The surgeon then chose to employ a Palmaz stent, to seal the endoleak. Balloon expansion in the ascending aorta was required in order to properly seat the Palmaz stent. Overdrive pacing at a rate of 220 beats min(-1), which lowered the systolic blood pressure (SBP) to 40s mmHg was used during this process after connecting the patient to a Zoll defibrillator with external pads. The Palmaz stent was successfully deployed at the proximal end of the previously deployed stent-graft, using a Tyshak balloon. The patient reverted to normal sinus rhythm with no evidence of ischemia at the conclusion of the overdrive pacing. No endoleak was appreciated after the Palmaz stent was placed.

Real-time ultrasound-guided spinal anesthesia in patients with predicted difficult anatomy.

BACKGROUND: There are limited reports of lumbar neuraxial blocks using real-time US in patients with predicted difficulties. We compared the number of attempts to perform spinal anesthesia using real-time US guidance versus landmark technique in patients meeting predefined criteria for difficult spinal anesthesia. We also compared procedure time, block success, patient satisfaction and difficulty scores between groups. METHODS: Following institutional review board approval patients scheduled for total hip or knee arthroplasty with expected difficulty to perform spinal anesthesia were included. Number of attempts, block time, success rate, patient satisfaction and difficulty scores were recorded and we conducted the Kruskal-Wallis non-parametric test of difference between the groups. RESULTS: Thirty-eight patients were enrolled and a total of 32 data sets was analyzed. For number of attempts, we observed no difference between the groups (P<0.83). The US group resulted in marginally higher time to block compared to the control (P<0.0653). The US group resulted in marginally higher satisfaction compared to the control group (P<0.09). The block success rate was 100% in both groups. Anesthesiologists rated the US group procedure more difficult than the control group (χ2=10.85, P<0.0010). CONCLUSIONS: This trial suggests that real-time US guidance for spinal anesthesia in challenging patients in comparison to the controlled group was completed in longer time, with lower needle insertion attempts, and higher patient satisfaction scores but without statistically significant differences.

A Double-Blind Randomized Controlled Trial Comparing Epidural Clonidine vs Bupivacaine for Pain Control During and After Lower Abdominal Surgery.

BACKGROUND: Alpha-2 adrenergic agonists produce safe and effective analgesia, but most investigations studying the analgesic effect of alpha-2 adrenoceptor agonists postoperatively included previous or concomitant administration of other analgesics. Because clonidine potentiates the effect of these drugs, its own intrinsic analgesic effect has been difficult to establish. This study was designed to compare the intraoperative and postoperative effects of epidural clonidine vs bupivacaine for patients undergoing lower abdominal surgery. METHODS: This randomized controlled trial included 40 patients aged 18-50 who were scheduled for elective lower abdominal surgery. Patients were randomly divided into 2 groups. Group I (n=20) received epidural clonidine; Group II (n=20) received epidural bupivacaine. Intraoperative and postoperative hemodynamics, pain scores, and complications were monitored. RESULTS: Mean pain scores were significantly lower in Group I compared to Group II (1.5 ± 0.5 compared to 3.4 ± 1.0, respectively) in the first 12 hours after surgery. Sedation was more prominent in Group I until 9 hours after surgery. Opioid requirements were significantly lower in Group I. Respiratory rate was similar in the 2 groups. Group I had larger decreases from baseline in systolic blood pressure and diastolic blood pressure than Group II. Heart rate in Group I was reduced from baseline, while it was increased in Group II. Less postoperative nausea and vomiting, urinary retention, pruritus, and shivering were observed in Group I. CONCLUSION: Compared to bupivacaine, epidural clonidine provided effective intraoperative and postoperative analgesia in selected patients, resulting in a decreased intravenous pain medication requirement and prolonged duration of analgesia after epidural infusion was discontinued.

Bilateral brachial plexus home going catheters after digital amputation for patient with upper extremity digital gangrene.

UNLABELLED: Peripheral nerve catheter placement is used to control surgical pain. Performing bilateral brachial plexus block with catheters is not frequently performed; and in our case sending patient home with bilateral brachial plexus catheters has not been reported up to our knowledge. Our patient is a 57 years old male patient presented with bilateral upper extremity digital gangrene on digits 2 through 4 on both sides with no thumb involvement. The plan was to do the surgery under sequential axillary blocks. On the day of surgery a right axillary brachial plexus block was performed under ultrasound guidance using 20 ml of 0.75% ropivacaine. Patient was taken to the OR and the right fingers amputation was carried out under mild sedation without problems. Left axillary brachial plexus block was then done as the surgeon was closing the right side, two hours after the first block was performed. The left axillary block was done also under ultrasound using 20 ml of 2% mepivacaine. The brachial plexus blocks were performed in a sequential manner. Surgery was unremarkable, and patient was transferred to post anesthetic care unit in stable condition. Over that first postoperative night, the patient complained of severe pain at the surgical sites with minimal pain relief with parentral opioids. We placed bilateral brachial plexus catheters (right axillary and left infra-clavicular brachial plexus catheters). Ropivacaine 0.2% infusion was started at 7 ml per hour basal rate only with no boluses on each side. The patient was discharged home with the catheters in place after receiving the appropriate education. On discharge both catheters were connected to a single ON-Q (I-flow Corporation, Lake Forest, CA) ball pump with a 750 ml reservoir using a Y connection and were set to deliver a fixed rate of 7 ml for each catheter. The brachial plexus catheters were removed by the patient on day 5 after surgery without any difficulty. Patient's postoperative course was otherwise unremarkable. We concluded that home going catheters are very effective in pain control postoperatively and they shorten the period of hospital stay. KEYWORDS: Brachial plexus; Home going catheters; Post-operative pain.