Sole Anesthetic Research Articles

Safety and efficacy of forefoot surgery under ankle block anaesthesia

Ankle block as the sole anaesthetic for forefoot surgery is not used uniformly throughout the UK despite obvious advantages and widespread use internationally. Evaluation of safety and effectiveness of performing elective forefoot surgery under ankle block anaesthesia alone in a pilot cohort of patients in a Scottish unit. Data were collected from 81 consecutive forefoot procedures (71 patients) using a standardised questionnaire including incremental pain assessment (0-10; 0 no pain, 10 severe pain). Seven patients reported pain during surgery; average score 0.17. Average pain scores 6, 12, 24 and 48 h following surgery were 1.5, 3.09, 2.3 and 1.9, respectively. All patients were discharged home and walking on the same day. Forefoot surgery under ankle block alone may be safe and effective. Anaesthesia obtained permitted routine forefoot procedures and provided lasting post-operative analgesia. Combined with intra-operative sedation, use of ankle tourniquet and same day discharge, it had very high patient acceptance and satisfaction.

Laparoscopic Cholecystectomy Under Spinal Anaesthesia vs. General Anaesthesia: A Prospective Randomised Study.

Laparoscopic cholecystectomy (LC) is conventionally performed under general anaesthesia (GA) in our institution. There are multiple studies which have found spinal anaesthesia as a safe alternative. We have conducted this study of LC, performed under spinal anesthesia to assess its safety and feasibility in comparison with GA. Fifty patients with symptomatic gallstone disease and American Society of Anesthesiologists status I or II were randomised to have LC under spinal (n = 25) or general (n = 25) anesthesia. Intraoperative vitals, postoperative pain, complications, recovery, and surgeon satisfaction were compared between the 2 groups. In the SA group six patients (24%) complained of shoulder pain, two patients required conversion to GA (8%) as the pain did not subside with Fentanyl. None of the patients in the SA group had immediate postoperative pain at operated site. Only two (8%) patients had pain score of 4 at the operative site within eight hours requiring rescue analgesic. One patient had nausea but no vomiting (4%). All the patients (100%) in the GA group had pain at operated site immediately after surgery and their pain score ranged from 4-7, all patients received rescue analgesic before shifting to the ward. In the first 24h tramadol required as rescue in the GA group was 82±24 mg which was significantly higher than the SA group requiring only 30±33.16 mg. Although, the GA group had more patients experiencing postoperative nausea & vomiting it was not statistically significant. SA as the sole anaesthesia technique is feasible, safe and cost effective for elective LC.

Invited Commentary

Invited Commentary

Regional Anesthesia Does Not Consistently Block Ischemic Pain: Two Further Cases and a Review of the Literature

Ischemic pain is complex and poorly understood. There is controversy regarding whether or not regional anesthetic techniques block ischemic pain. We present two further cases where regional anesthesia did not block ischemic pain despite adequate motor and sensory block. A 29-year-old healthy male underwent elective right lateral ankle ligament reconstruction for ankle instability with single-injection femoral and sciatic nerve blocks as the sole anesthetic. He reported no pain during or after surgery; approximately 90 min after the cast dressing was applied, he complained of severe pain in his medial ankle despite persistent complete sensory and motor blockade. The cast was removed, and he had immediate and complete resolution of his pain, which was thought to be due to ischemia. CASE REPORT 2: A 45-year-old female with a history of diabetes mellitus, hypertension, and 30 pack-year smoking history presented with increasingly cold, cyanotic, and painful fingers in her right hand. She suffered necrotic lesions of her 4th and 5th fingers accompanied by severe ischemic type pain. A continuous C7 cervical paravertebral block was placed. Despite dense sensory and motor blockade, she still reported excruciating pain that ultimately required amputation after developing demarcated gangrene. The two cases support the growing body of evidence that ischemic pain is largely unaffected by regional anesthesia, even with adequate sensory and motor block. The prevailing understanding regarding peripheral nerve blocks in patients in danger of developing compartment syndrome should be reconsidered.

Thoracic Paravertebral Nerve Block as the Sole Anesthetic for an Open Biopsy of a Large Anterior Mediastinal Mass

ANESTHESIA IN PATIENTS with anterior mediastinal masses still represents a major challenge for anesthesiologists. Tumors in this region can compress and obstruct vital mediastinal structures: the tracheobronchial tree in the region of the tracheal carina, the heart, the main pulmonary artery, and the superior vena cava. Most adult mediastinal tumors are asymptomatic or are associated with vague complaints such as chest pain or fullness, dyspnea, cough, sweats, superior vena cava obstruction, hoarseness, syncope, or dysphagia.

Hypnosis as sole anaesthesia for skin tumour removal in a patient with multiple chemical sensitivity

A female patient with multiple chemical sensitivity and previous anaphylactoid reactions to local anaesthetics was admitted for removal of a thigh skin tumour under hypnosis as sole anaesthesia. The hypnotic protocol included hypnotic focused analgesia and a pre-operative pain threshold test. After inducing hypnosis, a wide excision was performed, preserving the deep fascia, and the tumour was removed; the patient's heart rate and blood pressure did not increase during the procedure. When the patient was de-hypnotised, she reported no pain and was discharged immediately. Our case confirms the efficacy of hypnosis and demonstrates that it may be valuable as a sole anaesthetic method in selected cases. Hypnosis can prevent pain perception and surgical stress as a whole, comparing well with anaesthetic drugs.

Cultivating a “Chairside Manner”: Dental Hypnosis, Patient Management Psychology, and the Origins of Behavioral Dentistry in America, 1890–1910

Discussions regarding the use of hypnotism in dentistry featured prominently in dental journals and society proceedings during the decades around the turn of the twentieth century. Many dentists used hypnotic suggestion either as the sole anesthetic for extractions or in conjunction with local and general anesthetics for excavation and cavity filling. With the heralding of humanitarian dentistry and improved local anesthesia around 1905, a number of dentists advocated using suggestion psychology to calm nervous patients and increase their comfort and satisfaction levels while undergoing dental procedures. The practice of hypnotic suggestion with local and general anesthesia in providing patients with increasingly painless procedures constituted the earliest variety of behavioral dentistry, a discipline not fully developed until the closing decades of the twentieth century. Hypnosis and suggestion became driving forces for psychological applications in the formative years of behavioral dentistry.

Efficacy and safety of intrathecal pentazocine as a sole anesthetic agent for lower limb surgeries.

Context:The administration of opioids intrathecally as a sole anesthetic has proven to be effective in providing adequate surgical anesthesia without much hemodynamic instability.Aim:This study aims to determine the efficacy and safety of intrathecal pentazocine as a sole anesthetic drug in patients undergoing lower limb surgeries.Settings and Design:It was a randomized single blinded study conducted in 60 patients undergoing lower limb surgeries.Subjects and Methods:The patients were randomly divided into 2 groups of 30 patients in each group. Group A received 2 ml (60 mg) intrathecal pentazocine and Group B received 2 ml intrathecal 0.5% bupivacaine heavy before surgery. Duration of surgery, onset of sensory, and motor blockade and their duration, heart rate (HR), mean arterial pressure (MAP), and time for first rescue analgesia were statistically analyzed.Results:Group B showed a statistically significant earlier onset of sensory (2.54 ± 0.87 vs. 3.66 ± 1.10 min) and motor blocks (2.22 ± 0.77 vs. 3.29 ± 1.06 min). The majority of patients in the group A (30%) attained the highest level of sensory block of T11, whereas the majority in group B (33.3%) attained the highest level of sensory block of T8. Majority in the Group A (60%) showed a motor block of Bromage scale Grade III at the beginning of surgery, whereas the majority in Group B (80%) showed a motor block of Bromage scale Grade IV. Duration of sensory block was significantly prolonged in group B (124.33 ± 14.84 vs. 115.60 ± 18.39 min). However, duration of motor blockade was similar in both groups. Group B patients required first analgesia earlier than Group A (5.24 ± 1.98 h vs. 2.48 ± 0.51 h) which was significant. There was no difference between groups with regard to HR intra-operatively. On comparison of the pre-induction MAP between 2 groups, there was no difference. But later on at 1, 3, 5 min intervals, the MAP was less in group B. But at 10 and 15 min there was no significant difference between groups. The significantly reduced MAP in group B was evident again at 30, 45, and 60 min. There was no difference between groups at 90 and 120 min. Group B required first analgesia earlier than group A which was statistically significant.Conclusions:Because of adequate surgical anesthesia, intraoperative hemodynamic stability and prolonged post-operative analgesia, we recommend the use of intrathecal pentazocine as a sole anesthetic agent for lower limb surgeries.

Segmental thoracic spinal has advantages over general anesthesia for breast cancer surgery.

Background:Thoracic spinal anesthesia has been used for laparoscopic cholecystectomy and abdominal surgeries, but not in breast surgery. The present study compared this technique with general anesthesia in breast cancer surgeries.Materials and Methods:Forty patients were enrolled in this comparative study with inclusion criteria of ASA physical status I-III, primary breast cancer without known extension beyond the breast and axillary nodes, scheduled for unilateral mastectomy with axillary dissection. They were randomly divided into two groups. The thoracic spinal group (S) (n = 20) underwent segmental thoracic spinal anesthesia with bupivacaine and fentanyl at T5-T6 interspace, while the other group (n = 20) underwent general anesthesia (G). Intraoperative hemodynamic parameters, intraoperative complications, postoperative discharge time from post-anesthesia care unit (PACU), postoperative pain and analgesic consumption, postoperative adverse effects, and patient satisfaction with the anesthetic techniques were recorded.Results:Intraoperative hypertension (20%) was more frequent in group (G), while hypotension and bradycardia (15%) were more frequent in the segmental thoracic spinal (S) group. Postoperative nausea (30%) and vomiting (40%) during PACU stay were more frequent in the (G) group. Postoperative discharge time from PACU was shorter in the (S) group (124 ± 38 min) than in the (G) group (212 ± 46 min). The quality of postoperative analgesia and analgesic consumption was better in the (S) group. Patient satisfaction was similar in both groups.Conclusions:Segmental thoracic spinal anesthesia has some advantages when compared with general anesthesia and can be considered as a sole anesthetic in breast cancer surgery with axillary lymph node clearance.

Axillary Block as the Sole Anesthetic for Peripherally Inserted Central Catheter Placement in an Infant with Goldenhar Syndrome

The use of peripheral nerve block as the sole anesthetic in infants is not very common. Studies have demonstrated that ultrasound guided (USG) peripheral nerve block is associated with higher overall success rate when compared with nerve stimulation (Rubin et al., 2009, and Gelfand et al., 2011). Described below is a medically complex infant who had an USG axillary brachial plexus block for peripherally inserted central catheter (PICC) placement.

Supraclavicular Block as a Sole Anesthetic Technique in Craniopagus Twins

This is the first report in the literature of a sole regional anesthetic for adult craniopagus twins using a supraclavicular block for an elbow incision and drainage/bursa excision procedure. It demonstrates that for these complex medical patients, a total regional anesthesia technique is preferable when possible. There are several known general anesthetic complications in these patients. Anesthetic crossover between the twins can occur and may be variable; furthermore, the incidence and severity of the crossover effects of different anesthetics vary. Positioning of the twins can be difficult with both regional and general anesthesia. However, with regional anesthesia, the twins can position themselves and report any discomfort, which could go unnoticed under general anesthesia, leading to other complications. Craniopagus twins have a high likelihood of a difficult airway due to anatomy or positioning difficulties, which is avoided by regional anesthesia. This case emphasizes the unique challenges that these patients pose and the ability of regional anesthesia to help avoid the pitfalls of general anesthesia in these patients.

The Sequence of Administration of 1.5% Mepivacaine and 0.5% Bupivacaine Does Not Affect Latency of Block Onset or Duration of Analgesia in Ultrasound-Guided Interscalene Block

During peripheral nerve blockade, different local anesthetics may be sequentially administered. Typically, a short- or intermediate-acting local anesthetic is administered before a long-acting local anesthetic to achieve a block with rapid onset and long duration. However, there is a paucity of data on advantages of such sequencing. We hypothesized that when using a sequential mixture of mepivacaine and bupivacaine for ultrasound-guided interscalene block, the order of injection of the drugs does not influence the clinical characteristics of the block achieved. Sixty-four patients undergoing arthroscopic shoulder surgery (aged 18-65 years; ASA physical status I-II) with a single-injection ultrasound-guided interscalene brachial plexus block as sole anesthetic were studied. The subjects were randomized to receive 1 of 2 local anesthetic sequences: 15 mL of mepivacaine 1.5% followed by 15 mL of bupivacaine 0.5% (group A), or the same local anesthetics in the reverse order (group B). The durations of sensory and motor block were the primary outcomes. Block onset was also assessed. Duration of motor block was similar between group A and group B (10.1 ± 4.7 hours vs 10.3 ± 5.1 hours, mean difference 0.2 hours, 95% confidence interval [CI] -3.3 to 2.9, P = 0.9). Duration of analgesia was also similar between group A and group B (9.5 ± 5.6 hours vs 10.2 ± 4.5 hours, mean difference 0.7 hours, 95% CI -3.2 to 1.9, P = 0.42). Onset of sensory block was similar between the 2 groups (15.9 ± 7.1 minutes for group A, 13.9 ± 7.0 minutes for group B, mean difference 1.9 minutes, 95% CI -1.4 to 5.2, P = 0.25). The sequence in which 15 mL mepivacaine 1.5% and 15 mL bupivacaine 0.5% are administered does not seem to have a clinically meaningful effect on duration or onset of ultrasound-guided interscalene brachial plexus block.

Hemodynamic changes during spinal anesthesia in premature infants with congenital heart disease undergoing inguinal hernia correction

There are conflicting reports on the effects of spinal anesthesia (SA) on hemodynamics. Data on the hemodynamic effects of SA in infants with congenital heart disease (CHD) are limited. We reviewed our experience with 44 unsupplemented SA with 1 mg·kg(-1) of either hyperbaric tetracaine or bupivacaine in premature and former premature infants with noncyanotic CHD. Hemodynamics and oxyhemoglobin saturation (SpO(2)) were assessed. Neither preoperative fluid boluses nor atropine was administered to any of the infants. There was no significant change in systolic, diastolic, or mean blood pressures from pre-SA induction compared with end of surgery. Heart rate showed a small but systematic decline (mean change of 10 beats per minute, P < 0.01) but was within the normative range values for age. There was a small, but clinically insignificant increase in SpO(2) across the time course. Intraoperatively, two infants developed transient apneic spells. No infant developed postoperative apnea, oxygen desaturation, or bradycardia. The data suggest that SA with 1 mg·kg(-1) of either hyperbaric tetracaine or bupivacaine can be used safely as the sole anesthetic for inguinal hernia repair in infants with noncyanotic CHD even when fluid restricted and apparently causes minimal respiratory complications in these infants.

Remifentanil

The primary objectives were to review studies that used remifentanil in electroconvulsive therapy (ECT) and to determine whether remifentanil has potential advantages over other anesthetics. The author reviewed 12 original studies obtained through a MEDLINE database search that examined remifentanil as an anesthetic in patients receiving ECT. Remifentanil was associated with longer seizure durations when used as the sole anesthetic or as an adjunct when the primary anesthetic dose was lowered. Individual studies reported higher postictal suppression index and lower initial seizure thresholds and less rise in seizure thresholds with remifentanil. Data on hemodynamic effects were mixed but suggested favorable effects with remifentanil when seizure duration was not prolonged. Studies support the use of remifentanil in ECT, particularly in patients with brief seizures, high seizure thresholds, and postictal hemodynamic instability. Broad variability in study design, selection and dosing of anesthetics, electrode placement, and limited examination of potentially relevant variables such as age, sex, concomitant medications; and stimulus parameters attenuate the certainty of these results. Advantages in safety and efficacy over other anesthetics remain undetermined. Further study of remifentanil in ECT is warranted, given the methodological limitations and exclusion of important outcomes in the current literature.

Comparative study between intravenous and local dexamethasone as adjuvant to bupivacaine in perianal block

Background and objectivesEarly ambulation after hemorrhoidectomy as an outpatient procedure can be provided by perianal block with local anesthesia. The objective of this study was to compare the analgesic effects of dexamethasone locally and intravenously when combined with bupivacaine and to compare it with bupivacaine as a sole local anesthetic in the perianal block technique for ano-rectal surgeries.Patients and methods60 ASA I, 20–40 years of age male patients, undergoing ano-rectal surgeries under perianal block local anesthesia were randomly allocated to one of three groups: Bupivacaine group, Local dexamethasone (LD) group and Intravenous dexamethsone (IVD) group. Measurements included the onset of sensory and motor blockade, duration of analgesia, VAS at 6 h following rescue analgesic, and postoperative nausea and vomiting.ResultsThe onset of sensory and motor blockade was significantly shorter in the LD and IVD groups than in the bupivacaine group (3.8 ± 0.7, 4 ± 0.7 vs. 3.8 ± 0.9, 4 ± 1 vs. 5.5 ± 1.2, 6.5 ± 1.1, respectively, P < 0.01). The duration of analgesia was significantly prolonged in the LD and IVD groups compared to the bupivacaine group (287.7 ± 21 vs. 286.2 ± 16.9 vs. 162.3 ± 16.9, respectively, P < 0.01). Postoperative VAS was significantly lower in the LD and IVD groups compared to the bupivacaine group (1.8 ± 0.8 vs. 1.8 ± 0.8 vs. 4.7 ± 0.4, respectively, P < 0.01). The incidence of nausea and vomiting were significantly lower in the dexamethasone groups.ConclusionDexamethasone when used as an adjuvant to bupivacaine in the perianal block for ano-rectal surgeries can accelerate the onset of blockade and prolong the postoperative analgesia.

Research News: Nurse Anesthesia

IS THE PRACTICE of nurse anesthetists nursing? The American Association of Nurse Anesthetists (AANA), representing more than 42,000 Certified Registered Nurse Anesthetists (CRNAs), clearly defines the role as advanced practice nursing. Thehistory of nurse anesthetists is long and impressive. As early as theCivilWar (1861-1865), nurseswereproviding anesthesia care. In 1877, SisterMaryBernard of Pennsylvaniawas recognized as the first nurse to specialize in anesthesia. Today, few in the United States would argue against their legitimacy. ‘‘CRNAs practice in every setting where anesthesia is available and in some states are the sole anesthesia professionals in nearly 100% of rural hospitals.’’

The Effect of Mixing 1.5% Mepivacaine and 0.5% Bupivacaine on Duration of Analgesia and Latency of Block Onset in Ultrasound-Guided Interscalene Block

Short- and long-acting local anesthetics are commonly mixed to achieve nerve blocks with short onset and long duration. However, there is a paucity of data on advantages of such mixtures. We hypothesized that a mixture of mepivacaine and bupivacaine results in a faster onset than does bupivacaine and in a longer duration of blockade than does mepivacaine. Sixty-four patients undergoing arthroscopic shoulder surgery (ages 18 to 65 years; ASA physical status I-II) with ultrasound-guided interscalene brachial plexus block as the sole anesthetic were studied. The subjects were randomized to receive 1 of 3 study solutions: 30 mL of mepivacaine 1.5%, 30 mL of bupivacaine 0.5%, or a mixture of 15 mL each of bupivacaine 0.5% and mepivacaine 1.5%. The block onset time and duration of motor and sensory block were assessed. Onset of sensory block in the axillary nerve distribution (superior trunk) was similar among the 3 groups (8.7 ± 4.3 minutes for mepivacaine, 10.0 ± 5.1 minutes for bupivacaine, and 11.3 ± 5.3 minutes for the combination group; P = 0.21 between all groups). The duration of motor block for the combination group (11.5 ± 4.7 hours) was between that of the bupivacaine (16.4 ± 9.4 hours) and mepivacaine (6.0 ± 4.2 hours) groups (P = 0.03 between bupivacaine and combination groups; P = 0.01 between mepivacaine and combination groups). Duration of analgesia was the shortest with mepivacaine (4.9 ± 2.4 hours), longest with bupivacaine (14.0 ± 6.2 hours), and intermediate with the combination group (10.3 ± 4.9 hours) (P < 0.001 for mepivacaine vs. combination group; P = 0.01 for bupivacaine vs. combination group). For ultrasound-guided interscalene block, a combination of mepivacaine 1.5% and bupivacaine 0.5% results in a block onset similar to either local anesthetic alone. The mean duration of blockade with a mepivacaine-bupivacaine mixture was significantly longer than block with mepivacaine 1.5% alone but significantly shorter than the block with bupivacaine 0.5% alone.

Thoracic paravertebral anaesthesia for awake video‐assisted thoracoscopic surgery daily

Thoracic paravertebral blockade has been described as an effective alternative to epidural blockade for the management of postoperative pain after thoracic surgery. Here we present what we believe is the first description of the use of thoracic paravertebral block as the sole anaesthetic for video-assisted thoracoscopy. Two oncology patients with severe respiratory disease presented for video-assisted thoracoscopic surgery. Thoracic paravertebral block provided excellent surgical conditions and postoperative pain relief for these patients and allowed an optimal assessment of the anaesthetic impact on respiratory function.

Impact of Awake Videothoracoscopic Surgery on Postoperative Lymphocyte Responses

Surgical stress and general anesthesia can have detrimental effects on postoperative immune function. We sought to comparatively evaluate postoperative lymphocytes response in patients undergoing video-assisted thoracoscopic surgery (VATS) under thoracic epidural or general anesthesia. Between October 2008 and June 2009, 50 patients with nonmalignant pulmonary conditions were randomized to undergo VATS through either sole epidural anesthesia and spontaneous ventilation (awake group, n = 25) or general anesthesia with one-lung ventilation (control group, n = 25). In both groups, assessment of total lymphocytes count and changes in proportion of lymphocyte subsets including CD19+, CD3+, CD4+, CD8+, CD4+:CD8+ ratio, and CD16+CD56+ (natural-killer cell) were evaluated by two-way analysis of variance test for repeated measures at baseline and postoperative days 1, 2, and 3. The Mann-Whitney test was performed at each time point only for significant parameters at between-group analysis of variance. Comparisons of baseline data showed relatively homogeneous groups. Between-group analysis of variance was significant for proportion of natural-killer cells (p = 0.01). In particular, the control group disclosed a significantly lower median proportion of natural-killer cells as compared with the awake group on postoperative day 1 (5% interquartile range [IQR]: 3% to 8%] vs 12% [IQR: 8% to 14%], p = 0.003) and 2 (7% [IQR: 4% to 10%] vs 11% [IQR: 8% to 21%], p = 0.02). Total lymphocyte count was significantly decreased in the control group only (p < 0.00001). No difference was found between groups in the remaining lymphocyte subsets. In this randomized study, awake VATS resulted in a lesser impact on postoperative lymphocyte responses than procedures performed under general anesthesia, as shown by the significant difference in postoperative proportion of natural-killer cells.

Dexmedetomidine for anesthetic management of anterior mediastinal mass

Anesthetic management of anterior mediastinal masses (AMM) is challenging. We describe the successful anesthetic management of two patients with AMM in which dexmedetomidine was used at supra-sedative doses. Our first case was a 41-year-old man who presented with a 10 x 9 x 11 cm AMM, a pericardial effusion, compression of the right atrium, and superior vena cava syndrome. He had severe obstruction of the right mainstem bronchus, distal trachea with tumor compression, and endobronchial tumor invasion. Our second case was a 62-year-old man with tracheal and bronchial obstruction secondary to a recurrent non-small-cell lung cancer mediastinal mass. Both patients were scheduled for laser tumor debulking and treatment of the tracheal compression with a Y-stent placed through a rigid bronchoscope. Both patients were fiberoptically intubated awake under sedation using a dexmedetomidine infusion, followed by general anesthesia (mainly using higher doses of dexmedetomidine), thus maintaining spontaneous ventilation and avoiding muscle relaxation during a very stimulating procedure. The amnestic and analgesic properties of dexmedetomidine were particularly helpful. Maintaining spontaneous ventilation with dexmedetomidine as almost the sole anesthetic could be very advantageous and may reduce the risk of complete airway obstruction in the anesthetic management of AMMs.