Ali Sizlan

A Comparison of Gabapentin and Ketamine in Acute and Chronic Pain After Hysterectomy

BACKGROUND: Gabapentin and ketamine are popular analgesic adjuvants for improving perioperative pain management. We designed this double-blind, placebo-controlled study to test and compare the preventive effects of perioperative ketamine and gabapentin on early and chronic pain after elective hysterectomy. METHODS: Sixty patients undergoing abdominal hysterectomy were randomly assigned to 1 of the following 3 groups: control group received oral placebo capsules and bolus plus infusion of saline; ketamine group received oral placebo capsules and, before incision, 0.3 mg/kg IV bolus and 0.05 mg·kg−1·h−1 infusion of ketamine until the end of surgery; and gabapentin group received oral gabapentin 1.2 g and bolus plus infusion of saline. The anesthetic technique was standardized, and the postoperative assessments included verbal rating scales for pain and sedation, IV morphine usage, quality of recovery assessment, recovery of bowel function, resumption of normal activities, and patient satisfaction with their pain management. Patients were questioned at 1, 3, and 6 mo after surgery for chronic postoperative pain. RESULTS: Postoperative pain scores were significantly lower in the gabapentin group compared with the ketamine and control groups, and patient-controlled analgesia morphine use was significantly reduced in both treatment groups (versus control group) (P < 0.001). Total patient-controlled analgesia morphine use was decreased by 35% and 42% in the ketamine and gabapentin groups, respectively, compared with the control group (P < 0.001). Patient satisfaction with pain treatment was significantly improved in the ketamine and gabapentin groups compared with the control group (P < 0.001). The incidence of incisional pain and related pain scores at the 1-, 3-, and 6-mo follow-up were significantly lower in the gabapentin group compared with the ketamine and control groups (P < 0.001). CONCLUSION: Gabapentin and ketamine are similar in improving early pain control and in decreasing opioid consumption; however, gabapentin also prevented chronic pain in the first 6 postoperative months.

Spinal 5-HT7 receptors play an important role in the antinociceptive and antihyperalgesic effects of tramadol and its metabolite, O-Desmethyltramadol, via activation of descending serotonergic pathways.

Background:Tramadol is an analgesic drug, and its mechanism of action is believed to be mediated by the &mgr;-opioid receptor. A further action of tramadol has been identified as blocking the reuptake of serotonin (5-HT). One of the most recently identified subtypes of 5-HT receptor is the 5-HT7 receptor. Thus, the authors aimed to examine the potential role of serotonergic descending bulbospinal pathways and spinal 5-HT7 receptors compared with that of the 5-HT2A and 5-HT3 receptors in the antinociceptive and antihyperalgesic effects of tramadol and its major active metabolite O-desmethyltramadol (M1) on phasic and postoperative pain models. Methods:Nociception was assessed by the radiant heat tail-flick and plantar incision test in male Balb-C mice (25-30 g). The serotonergic pathways were lesioned with an intrathecal injection of 5,7-dihydroxytryptamine. The selective 5-HT7, 5-HT2, and 5-HT3 antagonists; SB-269970 and SB-258719; ketanserin and ondansetron were given intrathecally. Results:Systemically administered tramadol and M1 produced antinociceptive and antihyperalgesic effects. The antinociceptive effects of both tramadol and M1 were significantly diminished in 5-HT-lesioned mice. Intrathecal injection of SB-269970 (10 &mgr;g) and SB-258719 (20 &mgr;g) blocked both tramadol- and M1-induced antinociceptive and antihyperalgesic effects. Ketanserin (20 &mgr;g) and ondansetron (20 &mgr;g) were unable to reverse the antinociceptive and antihyperalgesic effects of tramadol and M1. Conclusions:These findings suggest that the descending serotonergic pathways and spinal 5-HT7 receptors play a crucial role in the antinociceptive and antihyperalgesic effects of tramadol and M1.

The effects of gabapentin on acute and chronic pain after inguinal herniorrhaphy.

Background and objective To find out whether preoperative gabapentin use had a favourable effect on long-term postoperative pain in patients undergoing inguinal herniorrhaphy. Methods Sixty male patients – aged 20–40 years – who were scheduled for unilateral inguinal herniorrhaphy under spinal anaesthesia were included in this prospective, randomized, double-blind study. The patients were randomly allocated to two groups: the gabapentin group (n = 30) received single-dose 1.2 g oral gabapentin 1 h before surgery, and the placebo group received a placebo capsule instead. Spinal anaesthesia was performed with heavy bupivacaine, and all operations were performed by the same surgeon with the same technique. Postoperative analgesia was evaluated during sitting and lying with a visual analogue scale. Assessment of postoperative pain at 1, 3 and 6 months was carried out with an 11-point numerical rating scale; 0 indicating ‘no pain’ and 10 indicating ‘worst pain imaginable’. Patients who had numerical rating scale scores of more than 0 were further evaluated with regard to the impact of pain on their daily activities. Results When compared with the placebo group, the gabapentin group displayed significantly lower visual analogue scale scores (lying and sitting) and total tramadol consumption at 8, 12, 16, 20 and 24 h after surgery (P < 0.05) and higher postoperative patient satisfaction scores (P < 0.05). Numerical rating scale scores at 1, 3 and 6 months after surgery were lower in the gabapentin group than in the placebo group (P < 0.05). The number of patients whose daily activities were adversely affected by pain was smaller in the gabapentin group at the first month; however, the two groups were found to be similar at 3 and 6 months. Conclusion We conclude that preoperative single-dose gabapentin decreases the intensity of acute postoperative pain, tramadol consumption and the incidence and intensity of pain in the first 6 months after inguinal herniorrhaphy.

Pressure-Controlled vs Volume-Controlled Ventilation During Laparoscopic Gynecologic Surgery

STUDY OBJECTIVE To quantify and compare the effects of conventional volume-controlled ventilation (VCV) with the alternative mode, pressure-controlled ventilation (PCV), on respiratory mechanics and noninvasive hemodynamic parameters in patients undergoing laparoscopic gynecologic surgery. DESIGN Randomized controlled trial (Canadian Task Force classification I). SETTING Respiratory mechanics and hemodynamic parameters were recorded for each patient at time T1, 10 minutes after induction, in the supine position; T2, 15 minutes after pneumoperitoneum, in the Trendelenburg position; and T3, 10 minutes after pneumoperitoneum withdrawal, in the supine position. PATIENTS Sixty women, aged 20 to 50 years, undergoing laparoscopic gynecologic surgery, with American Society of Anesthesiologists classes I and II disease. INTERVENTIONS Patients were randomly allocated to 1 of 2 groups. In the VCV group (n = 30), ventilation mode was maintained, whereas in the PCV group (n = 30), ventilation mode was changed to PVC. MEASUREMENTS AND MAIN RESULTS Both groups were comparable insofar as patient characteristics, operating time, pneumoperitoneum time, anesthesia time, and mean operative time. VCV was associated with a significant increase in peak airway pressure, plateau pressure, and airway resistance at T2 (p < .05). Compliance was significantly higher in the PCV group at T2 (p < .05). No other statistically significant differences were found between the groups. CONCLUSIONS Both VCV and PCV seem to be equally suited for use in patients undergoing laparoscopic gynecologic surgery. However, lower peak airway pressure, plateau pressure, and airway resistance, and higher compliance are observed with PCV in laparoscopic gynecologic surgery.

Ameliorative Effects of Proanthocyanidin on Renal Ischemia/Reperfusion Injury

Introduction. Several natural products have been reported to have beneficial effects on ischemia/reperfusion (I/R) injury, particularly from a preventative perspective. Therefore, this study was designed to investigate the efficiency of proanthocyanidin (PA), a natural product derived from grape seed, on renal dysfunction and injury induced by I/R of rat kidney. Materials and Methods. Twenty-four male Sprague-Dawley rats were divided into three groups: sham-operated, I/R, I/R+PA. Rats were given PA (100 mg/kg/day peroral) 7 days prior to I/R. All rats except sham-operated underwent 60 min of bilateral renal ischemia followed by 6 h of reperfusion. After reperfusion, kidneys and blood were obtained for evaluation. Superoxide dismutase, glutathione peroxidase, malondialdehyde, protein carbonyl content, and nitrite/nitrate level (NOx) were determined in the renal tissue. Serum creatinine (SCr), blood urea nitrogen (BUN), and aspartate aminotransferase (AST) were determined in the blood. Additionally, renal sections were used for histological grade of renal injury. Results. PA significantly reduced the I/R-induced increases in SCr, BUN, and AST. In addition, PA markedly reduced elevated oxidative stress product, restored decreased antioxidant enzymes, and attenuated histological alterations. Moreover, PA attenuated the tissue NOx, levels indicating reduced NO production. Conclusions. The pretreatment of rats with PA reduced the renal dysfunction and morphological changes, ameliorated cellular injury, and restored renal antioxidant enzymes caused by renal I/R.

Blood pressure changes in young male subjects exposed to a median altitude

ObjectiveResidence at high altitude has been associated with elevation in systemic blood pressure (BP), but few studies have been done on the time course and the effects of a median altitude. Moreover, there exist population differences in the reactions given to altitude and the mechanism is unknown. This study was therefore designed to determine the effects of a median altitude on resting BP and heart rate (HR) in a group of 15 healthy, young, Turkish male subjects.MethodsAfter basic measurements were carried out in Bursa (155 m), subjects were transported to a mountain hotel (altitude 1,860 m), where the measurements were repeated once every 15 days during a 10-month period.ResultsMean BP and diastolic BP increased on Day 4 and then remained above first values throughout the study. Compared with control measurements, high altitude increased systolic blood pressure (SBP) in all subjects, but in Month 4 and Month 6, SBP returned to control values, and remained elevated thereafter. HR continued to decrease in parallel with time and significant decrease occurred after Month 5.InterpretationOur findings imply that moderate-altitude living results in a significantly greater BP and lower HR over equivalent low-altitude measurements and we conclude that chronic exposure to hypobaric hypoxia at a median altitude causes increased parasympathetic and sympathetic tone in healthy, young, Turkish males.

A Novel Treatment of Chronic Orchialgia

We evaluated the effectiveness of pulsed radiofrequency (PRF) denervation of spermatic cord for the treatment of chronic orchialgia. Five patients diagnosed with chronic orchialgia were evaluated with a thorough medical and psychiatric history, physical examination, and scrotal Doppler ultrasound, urinary system x-ray film, and urine analyses. One of the patients had bilateral chronic orchialgia. All of the patients had pain for a period of at least 3 months, and multiple conservative therapies failed to alleviate the pain. The patients, who had temporary pain relief after undergoing outpatient diagnostic cord block, were determined to be candidates for PRF denervation. PRF denervation of spermatic cord was performed for 6 testicular units. Visual analog scores were noted before and after the procedure. There were no pathologic conditions that indicated chronic orchialgia in any of the patients. No complications, including testicular atrophy or hypoesthesia of the scrotal or penile skin, occurred after the procedure. Mean visual analog scores before and after the procedure were 9 and 1, respectively. None of the patients needed any analgesics after the procedure or during the follow-up period. Mean follow-up period was 20 ± 2.5 weeks. No recurrence was noted, and none of the patients needed additional therapy. This is a limited case report on the short-term use of PRF. Randomized, placebo-controlled, and long follow-up period studies are needed to better assess the efficacy of this procedure for chronic orchalgia.

Hearing impairment associated with spinal anesthesia

Objectives Hearing loss after spinal anesthesia has been reported to be related to the transmission of a reduced subarachnoid pressure to the inner ear via the cochlear aqueduct due to loss of spinal fluid. However, there are also some controversies related to this phenomenon, which require systematic investigation. Material and Methods The effect of spinal needle diameter on hearing loss was investigated using audiometric tests in a prospective comparative study of 30 patients who were scheduled for surgery with spinal anesthesia. The bony structure of the cochlear and vestibular aqueducts was determined from temporal bone CT scans. Results Four out of 15 patients (26.67%) treated with a 22 G spinal needle demonstrated hearing loss the day after surgery, which recovered within 2–5 weeks. However, none of the patients treated with a 27 G spinal needle had statistically significant hearing loss in either ear at any frequency. Three out of four patients with hearing loss had an acute-onset balance problem. There was no difference between the two groups in terms of the widths of the vestibular and cochlear aqueducts. Conclusions It has been shown audiometrically that the diameter of the spinal needle used to induce spinal anesthesia seems to have an effect on subsequent hearing loss. The patency of the bony canal determines the transmission of pressure changes to the inner ear. However, the individual risk of this complication is not predictable as there is no radiological abnormality of the canal.

Accuracy of caudal epidural injection: the importance of real-time imaging.

Abstract:  Caudal epidural steroid injections are often used for low back pain. Fluoroscopic guidance has been frequently cited as a requirement for this procedure.

Efficacy of different concentrations of sevoflurane administered through a face mask for magnetic resonance imaging in children

Background:  The main aim of this study was to use a non‐invasive method such as a face mask to maintain anesthesia in children during magnetic resonance imaging (MRI). The secondary aim was to ascertain hemodynamic‐respiration parameters, recovery time and complications of anesthesia with the administration of different concentrations of sevoflurane.