Anesthesiology and Pain Medicine
Year:2015 | Volume:5 | Issue:1|Papers Count:16

Background: Extraperitoneal laparoscopy has become a common technique for many surgical procedures, especially for inguinal hernia surgery. Investigations of physiological changes occurring during extraperitoneal carbon dioxide (CO2) insufflation mostly focused on blood gas changes. To date, the impact of extraperitoneal CO2 insufflation on respiratory mechanics remains unknown, whereas changes in respiratory mechanics have been extensively studied in intraperitoneal insufflation.Objectives: The aim of this study was to investigate the effects of extraperitoneal CO2 insufflation on respiratory mechanics.Patients and Methods: A prospective and observational study was performed on nine patients undergoing laparoscopic inguinal hernia repair. Anesthetic management and intraoperative care were standardized. All patients were mechanically ventilated with a tidal volume of 8 mL/kg using an Engstrom Carestation ventilator (GE Healthcare). Ventilation distribution was assessed by electrical impedance tomography (EIT). End-expiratory lung volume (EELV) was measured by a nitrogen wash-out/wash-in method. Ventilation distribution, EELV, ventilator pressures and hemodynamic parameters were assessed before extraperitoneal insufflation, and during insufflation with a PEEP of 0 cmH2O, 5 cmH20 and of 10 cmH20.Results: EELV and thoracopulmonary compliance were significantly decreased after extraperitoneal insufflation. Ventilation distribution was significantly higher in ventral lung regions during general anesthesia and was not modified after insufflation. A 10 cmH20 PEEP application resulted in a significant increase in EELV, and a shift of ventilation toward the dorsal lung regions.Conclusions: Extraperitoneal insufflation decreased EELV and thoracopulmonary compliance. Application of a 10 cmH20 PEEP increased EELV and homogenized ventilation distribution. This preliminary clinical study showed that extraperitoneal insufflation worsened respiratory mechanics, which may justify further investigations to evaluate the clinical impact.

Background: Arthroscopic knee surgeries have a painful postoperative course, which often necessitates acute pain management. Among different analgesia techniques, Intra-articular injection is the technique of choice for many pain specialists, based on its confined effect to the surgical site (knee), lack of systemic effects and promotion of safe early ambulation.Objectives: The aim of this study was to compare analgesic effects of intra-articular meperidine, bupivacaine 0.5% or their combination after knee arthroscopic surgery.Patients and Methods: Sixty ASA class I-II patients’ candidates for arthroscopy knee surgery enrolled in a randomized double blind study to receive either 20 mL of bupivacaine 0.5%; 100 mg meperidine (diluted in normal saline) or bupivacaine 0.5% along with 100 mg meperidine. A written informed consent was obtained from all patients. Postoperative analgesia duration, VAS at 2, 6, 12 and 24 hours, the first analgesic request time, total fentanyl consumption in first 24 hours, patients’ satisfaction and adverse effects were recorded.Results: The bupivacaine-meperidine group had better duration of postoperative analgesia (P=0.001), latter first analgesic request (P≤0.001), lower total fentanyl consumption in first 24 hours after the operation (P=0.001), less mean VAS at 2 hours (P=0.001) and more patients’ overall satisfaction (P=0.01) compared with each medication alone. VAS at 6, 12 and 24 postoperative hours were not different between the groups of study. No adverse effects were observed.Conclusions: Although postoperative intra-articular meperidine is a better alternative for bupivacaine, their combination could improve their analgesic effects compared with each other alone.

Background: Cancer pain may be a major problem for health care providers worldwide. According to different studies reporting the pain severity, one-third of patients reported to have moderate to severe pain. Management of cancer pain is one of the most important goals of palliative care. Recently, different research results on the efficacy of opioid analgesics in chronic pain management have played a role to implement standards in pain control by government agencies worldwide.Objectives: This study aimed to investigate the efficacy of fentanyl transdermal patch in the treatment of chronic soft tissue cancer pain.Patients and Methods: In a prospective descriptive study, we evaluated 86 patients with soft tissue tumors with chronic pain referred to cancer institute of Imam Khomeini Hospital, Tehran, Iran, during 2006-2007. For all patients, transdermal fentanyl patch (25 mg/h) was administered. The appearance of patches was the same. Pain severity was measured by Visual Analogue Scale (VAS) initially and 24, 48 and 72 hours after the initiation of treatment.Results: Patients' characteristics and VAS score before the treatment were not significantly different (P>0.05). According to our findings, the pain severity was significantly reduced after the treatment (P=0.001). The incidence of adverse events in patients was significantly high (72%). The most common adverse events were sleepiness, nausea and vomiting in 30.2% and 18.6%, respectively.Conclusions: Transdermal fentanyl patch was an effective and safe method to reduce pain in patients with soft tissue tumors. Moreover, it could improve the quality of life in these patients, but adverse events occurred in approximately 72% of patients.

Introduction: Facet joint pain affects 5% to 15% of the population with low back pain and the prevalence increases with age due to progression of arthritis. While conservative treatments are often unsuccessful, the scientific evidence on minimally invasive therapies such as intra-articular steroid infiltration and continuous and pulsed radiofrequency (PRF) of the medial branches is contradictory. Since PRF has recently been reported to successfully treat joint pain, a new application of this method is proposed for facetogenic lumbar pain via an intra-articular subcapsular approach. Here we reported two cases with successful treatment.Case Presentation: A 71-year-old patient presented because of persisting pain in the left gluteal region radiating to the lateral thigh and calf when standing. Anti-inflammatory drugs produced only short-lasting insufficient relief. A 52-year-old employee was admitted in June 2012 because of axial lower lumbar pain with intermittent diffuse radiation to the right lower extremity that worsened during walking and lying down despite receiving analgesics and physiotherapy.Conclusions: A new approach to treat lumbar facet joint pain with PRF is simple to perform and without serious complications. In view of the good long-lasting results obtained with the two reported cases, randomized control trials are necessary to validate this new approach.

Background: Patency of the revascularization conduit is an essential predictor of long-standing survival after coronary artery bypass grafting.Objectives: We have conducted this study to compare the mid-term patency rates of radial artery (RA), left internal thoracic artery (LITA) and also saphenous vein (SV) grafts in asymptomatic patients following coronary artery bypass graft surgery (CABG) undergoing total IV anesthesia.Patients and Methods: In this study, 30 three-vessel disease patients with 104 RA, LITA, and SV grafts used concomitantly for primary isolated non-emergent CABG surgery were assessed. The primary end point was CT angiographic graft patency rate. After 53.5 (24-97) months’ follow-up, graft patency was assessed using 128-slice CT coronary angiography. Logistic regression analysis was used to detect the independent predictors of graft failure.Results: A total of 104 grafts, including 30 LITA, 44 SV, and 30 RA grafts, were studied. Cumulative graft patency rates were 93.3% in LITA, 83.3% in RA, and 70.5% in SV grafts. Statistically significant difference was found between the LITA and the SV graft patency rates (P=0.019), whereas the difference between the RA conduit patency and the LITA or SV graft patency rates did not have any statistical significance (P=0.424 and P=0.273, respectively). Independent predictors of RA grafts occlusion were native coronary stenosis <70% and female gender.Conclusions: In our patients, the RA grafts had an acceptable patency rate in 2 to 5 years’ follow-up. Although the SV grafts had a relatively higher patency rate than RA grafts in our asymptomatic patients, the patency rates in RA and SV grafts were close to each other. The RA graft function was poor in the patients with a higher number of risk factors and in the females.

Context: The liver as an important organ in the body has many essential functions in physiological processes. One of the major activities of liver is drug metabolism. Hepatic dysfunction affecting hepatic physiological activities, especially drug metabolism can cause many problems during anesthesia and administration of different drugs to patients.Evidence Acquisition: Studies on hepatic disorders and hypnotic anesthetics prescribed in hepatic disorders were included in this review. For this purpose, reliable databases were used.Results: Anesthesia should be performed with caution in patients with hepatic dysfunction and drugs with long half-life should be avoided in these patients.Conclusions: A review of the literature on the use of hypnotic drugs in patients with liver dysfunction showed that some hypnotic drugs used during anesthesia could be safely used in patients with impaired liver function. In these patients, certain drugs should be used with caution.

Background: Intravenous regional block, called the Bier's block, refers to an analgesic technique applied for soft tissue surgeries and closed bone manipulations of the limbs. There are a number of complications in traditional method of block, including pain in tourniquet site, immediate return of pain after tourniquet deflation, wound hemostasis and some others.Objectives: The aim of this study was to assess the outcomes and complications of our new method of blockage.Patients and Methods: In this experimental study, twenty-five patients undergoing hand surgery were prospectively studied. Induced anesthesia was a modification of the Bier's block with two concurrent changes including insertion of the intravenous cannula at the antecubital region rather than distal and the proximal anesthetic direction by an elastic band wrapped tightly around the proximal forearm distal to the cannulation site. The pain relief was measured by the verbal descriptive scale at intervals after block, during the operation, after deflation of the tourniquet and one hour after the operation.Results: This study showed the presence of analgesia at surgical and tourniquet sites during the operation in 96% of patients, as well as considerable pain relief at surgical site during one hour after deflation of the tourniquet.Conclusions: The study indicated advantages of this modified Bier's block compared to the traditional one including ability to perform surgery on upper limb bones and considerable pain relief at surgical and tourniquet sites during the operation until one hour thereafter.

Background: Magnesium is a physiologic cation that blocks neuromuscular transmission and does not allow the nerve to be stimulated.Objectives: This study investigates the effect of adding magnesium sulfate to lidocaine to extend the duration of sensory and motor blocks of the axillary plexus in orthopedic surgeries of the upper extremities.Patients and Methods: This controlled randomized double-blind study was performed on patients who were candidates for orthopedic surgery of the upper extremities. A total of 60 patients between 18-60 years with ASA Class 1 or 2 participated in the study. One group received lidocaine (5 mg/kg) with magnesium sulfate 20% (3 mL) as the case group, while the second group received lidocaine (5 mg/kg) with normal saline (3 mL) as a placebo to block the axillary plexus using the trans-arterial technique. The duration of the sensory and motor block of the axillary plexus was monitored and evaluated using the pinprick and modified Bromage scale. Results: A total of 60 patients were included in the study with 30 patients having received lidocaine plus magnesium and the other 30 patients having received lidocaine plus normal saline. The mean sensory block duration in the case group was 248.83±18.36 and in control group was 204.67±22.62. The mean motor block duration in the case group was 207.0±16.64 and in control group was 147.33±21.52 (both P<0.0001). The mean onset of sensory block in case group was 15.5±3.79 and the onset block in control group was 10.33±4.13 (P<0.0001). The mean onset of motor block in case group was 20.66±4.09 and the onset block in control group was 19.73±26.18 (P<0.848).Conclusions: The addition of magnesium sulfate to lidocaine increased the duration of motor and sensory axillary block in the upper extremities during surgeries when compared to the use of lidocaine alone.

Background: Pain after laparoscopic gastric bypass surgery (LGBP) is a major problem. Gabapentin is an anticonvulsant drug that can be effective in postoperative pain control.Objectives: This study examined the effect of preoperative administration of gabapentin on reducing pain after LGBP in patients with morbid obesity.Patients and Methods: This randomized clinical trial was performed in Hazrat Rasoul Akram Medical Center in Tehran. A total of 60 patients undergoing LGBP were randomly allocated into two groups; one group received 100 mg of oral gabapentin and the other group received placebo. Pain was evaluated at recovery time, and at the first, second, fourth and sixth hour of surgery by visual analog scale. The number and dose of opioid use after surgery and incidence of postoperative complications, such as nausea and vomiting, agitation, and headache, were also recorded.Results: The mean pain score in the group receiving gabapentin was significantly lower than the placebo group (P<0.001). Indications and dose of opioid consumption between the two groups were not statistically significant. Incidence of nausea/vomiting (P=0.028) as well as agitation (P=0.037) was significantly lower in the gabapentin group.Conclusions: Administration of gabapentin before surgery can reduce pain after LGBP. Furthermore, it is not accompanied by significant short-term adverse effects.

Background: Prolonged intensive care unit (ICU) and hospital stay after cardiac surgery is vitally important and is influenced by both intraoperative and postoperative factors.Objectives: This randomized clinical trial study was designed to assess whether vitamin C supplementation could reduce the length of ICU and hospital stay in post-cardiac surgery patients.Patients and Methods: Two hundred and ninety patients scheduled for adult cardiac surgery including coronary, valve and congenital operations were randomized into two groups: an intervention group, who received 2 g of vitamin C (ascorbic acid) intravenously, immediately before surgery in the operating theatre, followed by 1 g daily oral doses for the first 4 postoperative days; and a placebo group, who received an equal number of identical tablets in the same shape and size.Results: Hospital length of stay was significantly different between the two groups (10.17± .63 days in the intervention group vs. 12±4.51 days in the placebo group; P=0.01), while there was no significant difference in the ICU stay between the groups (3.42±1.06 days in intervention group vs. 3.43±1.09 days in the placebo group; P=0.88). There were significant differences in the intubation time and the drainage volume in the ICU and the first 24 postoperative hours between the two groups (P for both=0.003).Conclusions: Vitamin C can decrease the length of hospital stay, drainage volume in the ICU and in the first 24 postoperative hours, intubation time and some complications in patients after cardiac surgery; perhaps by decreasing inflammatory factors.

Background: An unresolved question is the time required for the ability to return to complex tasks following anesthesia.Objectives: This study aims to characterize the severity and duration of cognitive impairment following sevoflurane or desfluane anesthesia after brief surgery using tests of cognitive ability to objectively testing performance.Patients and Methods: This study is a double blinded randomized controlled trial. Patients were randomized to receive either a desflurane or sevoflurane-based anesthetic. On the morning of the surgery the subjects performed baseline cognitive task tests (Mini Mental Status exam, Trail Making Test Part A and B, Digit Symbol Coding, Hopkins Verbal Learning Test, Stroop Color and Word Test to determine baseline cognitive function. Cognitive testing was repeated 30 minutes and 1 hour after surgery whereas Modified Telephone Interview for Cognitive Status (TICS-M) and Memory Aging Telephone Screen (MATS) was used on the following day of surgery.Results: Trail Making Test Part B cognitive test showed statistically significant in comparison for pre and post exposure of anesthetics. This difference was seen in the desflurane group. Other cognitive tests did not show differences on exposure to the anesthetic gases.Conclusions: This study questioned the difference between volatile anesthetic agent’s effects on patients completing a battery of neurocognitive tests attempting to answer if one agent has a more profound effect. Our study shows no statistically significant cognitive decline except for those in the Trail Making Part B in the Desflurane group. This conclusion is limited by the inherent limitations of the study, but does reinforce that the systemic inflammatory response from the surgery contributes cognitive impairment.

Context: Lumbar central spinal stenosis is common and often results in chronic persistent pain and disability, which can lead to multiple interventions. After the failure of conservative treatment, either surgical or nonsurgical modalities such as epidural injections are contemplated in the management of lumbar spinal stenosis.Evidence Acquisition: Recent randomized trials, systematic reviews and guidelines have reached varying conclusions about the efficacy of epidural injections in the management of central lumbar spinal stenosis. The aim of this systematic review was to determine the efficacy of all three anatomical epidural injection approaches (caudal, interlaminar, and transforaminal) in the treatment of lumbar central spinal stenosis. A systematic review was performed on randomized trials published from 1966 to July 2014 of all types of epidural injections used in the management of lumbar central spinal stenosis. Methodological quality assessment and grading of the evidence was performed.Results: The evidence in managing lumbar spinal stenosis is Level II for long-term improvement for caudal and lumbar interlaminar epidural injections. For transforaminal epidural injections, the evidence is Level III for short-term improvement only. The interlaminar approach appears to be superior to the caudal approach and the caudal approach appears to be superior to the transforaminal one.Conclusions: The available evidence suggests that epidural injections with local anesthetic alone or with local anesthetic with steroids offer short- and long-term relief of low back and lower extremity pain for patients with lumbar central spinal stenosis. However, the evidence is Level II for the long-term efficacy of caudal and interlaminar epidural injections, whereas it is Level III for short-term improvement only with transforaminal epidural injections.

Complex regional pain syndrome (CRPS) is outlined as a painful and disabling syndrome accompanied by physical changes within the affected extremity, together with allodynia, edema, and baldness, yet as sudomotor and dilatation dysfunction CRPS has been reported most often in adult population, but it has been reported in pediatric population as well.

Background: For coronary artery bypass grafting (CABG) sternotomy should be performed. The pain after surgery is severe and requires medical intervention. Use of the analgesics is limited by their side effects and studies suggest that prevention with some medications before surgery is effective in controlling the postoperative pain.Objectives: We investigated the efficacy of pregabalin administration before surgery in the treatment of acute postoperative pain after CABG surgery.Patients and Methods: Sixty patients indicated for elective CABG surgery were randomly allocated to two groups. One group received placebo and the other received 150 mg of oral pregabalin before surgery. Heart rates, blood pressure, respiratory rate, intensive care unit (ICU) stay duration, morphine consumption, and pain score according to the visual analog scale (VAS) were measured and recorded at 4, 12, and 24 hours of surgery. Results: Pregabalin consumption did not alter hemodynamic parameters and was safe in patients after CABG. Its consumption was associated with significant reduction in the pain score (P values were 0.035, 0.026, and 0.047 respectively at 4, 12, and 24 hours of surgery). Its use was not associated with changes in the morphine consumption at 4, 12, and 24 hours of surgery (P>0.05).Conclusions: Premedication with studied dose of pregabalin is effective for the prevention of postoperative pain in patients after CABG and has no adverse effects. Trials with other treating schedule and doses of the drug should be performed to determine the best treatment plan.

Background: Postoperative bleeding after cardiac reoperations is among the most complicating problems, both for the physicians and for the patients. Many modalities have been used to decrease its adverse effects and the need for blood products administration.Objectives: In a randomized double-blinded clinical trial of redo cardiac valve surgery in adult, the effect of active recombinant factor VII (rFVIIa) on postoperative bleeding was compared with placebo. Chest tube drainage was used for comparison of bleeding between the two groups.Patients and Methods: Two groups of 18 patients undergoing redo valve surgeries were treated and compared regarding chest tube drainage, need for blood products, prothrombin time (PT), partial thromboplastin time (PTT), hemoglobin and hematocrit, platelet count, and international normalized ratio (INR) in first 24 hours after surgery. Bleeding was assessed at 3rd, 12th, and 24th hour after operation. In rFVIIa group, 40 mg/kg of AryoSeven was administered before end of surgery and same volume of normal saline was administered as placebo in the control group.Results: Study groups showed no difference regarding baseline variables. Three patients in rFVIIa group (16.67%) and 13 in placebo group (72.23%) received blood products (P<0.01). Chest tube blood drainage at 24th hour after operation was 315±177 mL in rFVIIa group and 557±168 mL in control group (P=0.03). At third and 12th hour after operation, the difference was not statistically significant (P=0.71 and P=0.22, respectively). Postoperative ICU stay was not different; while extubation was longer in the placebo group (352±57 vs. 287±46 minutes; P=0.003).Conclusions: Our study demonstrated the efficacy of rFVIIa in controlling postoperative bleeding in redo cardiac valve surgeries regarding subsequent blood loss and transfusion requirement; however, outcome results remains to be defined.

Context: Anesthetic drugs including halogenated anesthetics have been common for many years. Consequent hepatic injury has been reported in the literature. The mechanism of injury is immunoallergic. The first generation drug was halothane; it had the most toxicity when compared to other drugs. The issue becomes more important when the patient has an underlying hepatic dysfunction.Evidence Acquisition: In this paper, reputable internet databases from 1957-2014 were analyzed and 43 original articles, 3 case reports, and 3 books were studied. A search was performed based on the following keywords: inhalational anesthesia, hepatic dysfunction, halogenated anesthetics, general anesthesia in patients with hepatic diseases, and side effects of halogenated anesthetics from reliable databases. Reputable websites like PubMed and Cochrane were used for the searches.Results: In patients with hepatic dysfunction in addition to hepatic system and dramatic hemostatic dysfunction, dysfunction of cardiovascular, renal, respiratory, gastrointestinal, and central nervous systems may occur. On the other hand, exposure to inhalational halogenated anesthetics may have a negative impact (similar to hepatitis) on all aforementioned systems in addition to direct effects on liver function as well as the effects are more pronounced in halothane.Conclusions: Despite the adverse effects of inhalational halogenated anesthetics (especially halothane) on hepatic patients when necessary. The effects on all systems must be considered and the necessary preparations must be provided. These drugs are still used, if necessary, due to the presence of positive effects and advantages mentioned in other studies as well as the adverse effects of other drugs.