Effect of Dexmedetomidine Combined with Inhalation of Isoflurane on Oxygenation Following One-Lung Ventilation in Thoracic Surgery.

BACKGROUND: One-lung ventilation (OLV) is commonly used during thoracic surgery. At this time, hypoxemia is considered one of the remarkable consequences of the anesthesia management. Hypoxic pulmonary vasoconstriction (HPV) is the defense mechanism against hypoxia. OBJECTIVES: The aim of the present study was to investigate the effect of infusion of dexmedetomidine on improving the oxygenation during OLV among the adult patients undergoing thoracic surgery. METHODS: A total of 42 patients undergoing OLV by general anesthesia with isoflurane inhalation were randomly assigned into two groups: IV infusion of dexmedetomidine at 0.3 microgram/kg/h (DISO) and IV infusion of normal saline (NISO). Three Arterial Blood Gas (ABG) samples were obtained throughout the surgery. Hemodynamic parameters, PaO2, PaCO2, and complications at recovery phase were recorded. The collected information was analyzed using SPSS software version 22. RESULTS: In the dexmedetomidine group, the mean hemodynamic parameters had a significant reduction at 30 and 60 minutes following OLV. Administration of dexmedetomidine resulted in a significant increase in the PaCO2 and a reduction in the PaO2 when changing from two-lung ventilation to OLV, where PaO2 reached its maximum value within 10 minutes after OLV in the DISO group, and it began to gradually increase to the end of operation. The duration of the recovery phase, also complications at the recovery phase decreased significantly in DISO group. CONCLUSIONS: The results of the study showed that, dexmedetomidine may improve arterial oxygenation during OLV in adult patients undergoing thoracic surgery, and can be a suitable anesthetic agent for thoracic surgery.

Determination of the diagnostic value of the Modified Mallampati Score, Upper Lip Bite Test and Facial Angle in predicting difficult intubation: A prospective descriptive study.

BACKGROUND: Difficult intubation is a significant cause of mortality and morbidity related to anesthesia. We decided to evaluate the value of Modified Mallampati Score, Upper Lip Bite Test and Facial Angle in the prediction of difficult intubation. METHODS: In a prospective descriptive study, data from 132 patients who were candidates for elective maxillofacial surgeries under general anesthesia were gathered. Facial Angles were measured by a maxillofacial surgeon according to cephalometry. The Modified Mallampati Score and Upper Lip Bite Test were first measured by an anesthesiologist and then another anesthesiologist was assigned to record the Cormack and Lehane score during the intubation. Grades 3 and 4 were considered as difficult intubation. Sensitivity, specificity, positive predictive value, negative predictive value and Youden index were calculated for all tests. RESULTS: Difficult intubation was reported in 12% of the patients. Facial Angle≤82.5° can predict difficult intubation with 87.5% sensitivity and 88.8% specificity. Among the three tests, a high Modified Mallampati Score had the highest specificity (94.5%) and a high Modified Mallampati Score and Facial Angle (FA≤82.5°) had the highest sensitivity (87.5%). The highest NPV, sensitivity and Youden index were observed when using Facial Angle with the Modified Mallampati Score or with Upper Lip Bite Test. CONCLUSIONS: Facial Angle has a high sensitivity, NPV and Youden index for the prediction of difficult intubation, but the best result is achieved when Facial Angle is used in combination with either the Modified Mallampati Score or Upper Lip Bit Test.

Hemodynamic Changes following Anesthesia Induction and LMA Insertion with Propofol, Etomidate, and Propofol + Etomidate.

INTRODUCTION: LMA is a simple supra-laryngeal device which is used to establish and maintain airway. Despite the common use of the LMA, there are no optimal methods for induction of anesthesia that can guarantee a proper insertion. The purpose of this study is comparing three methods of induction of anesthesia (Propofol, Etomidate, Propofol+Etomidate) in the hemodynamic stability after LMA insertion in elective surgeries. METHODS: A total of 90 patients with ASA classes I and II undergoing elective surgeries were randomly allocated into one of the following three groups. Before anesthesia induction, all patients were premedicated. Anesthesia induction methods included: Group P (propofol 2.5 mg/kg), Group E (etomidate 0.3 mg/kg) and Group P+E (propofol 1 mg/kg plus etomidate 0.2 mg/kg). Heart rate, systolic blood pressure, diastolic blood pressure, and mean arterial pressure were measured before induction and 30 seconds after induction. Apnea time is recorded in all patients. Number of attempts to laryngeal mask insertion, ease of placement, were compared in three groups. RESULTS: There was no significant difference between demographic data and BIS, SaO2, Etco2 associated diseases, in three group (P>0.5).There is significant difference in hemodynamic (Systolic, diastolic and mean blood pressures) changes between group 1 in comparison with group 2 and group 3. HR was significantly lower in group 1 than group 2 (P=0.16). There was significant difference in the number of attempts and ease of LMA insertion between group 2 in comparison with group 3 and group 1. The duration of apnea in group 2 was a (8.67± 6) min, where as it was (18.10±6.25) min in group 1 and (12.03±6.4) min group 3. CONCLUSION: Etomidate plus propofol is an effective and alternative to propofol and etomidate for facilitating LMA insertion with the added advantage of lack of cardio-vascular depression.

Assessment of Mini-dose Succinylcholine Effect on FacilitatingLaryngeal Mask Airway Insertion.

INTRODUCTION: Laryngeal Mask Airway (LMA) has gained wide acceptance for routine airway management and with increasing emphasis on day care surgery it is widely used. The aim of this study was to assess the effects of mini dose succinylcholine (0.1mg/kg) with semi-inflated cuff on facilitation of laryngeal mask airway insertion in order to achieve more satisfaction yet less complications . METHODS: In a randomized double-blinded study, sixty ASA 1, 2 and 3 patients aged 20-60 years scheduled for urologic surgical procedures were included. Thirty patients received succinylcholine (Group S), and thirty received 0.9% sodium choride as a placebo (Group C). RESULTS: Coughing occured in 33.3% of patients in the control group and there was no incidence in succ group (P=0.002). Head or limb movement occurred in 70% of the patients in the control group vs. 10% in succ group (P<0.001). Laryngospasm occurred in 36.6 % of the patients in the control group but there was no incidence in succ group (P=0.004). Additional propofol was required in 53% of the patients in control group vs. 10% for succ group (P=0.001). Ease of insertion and first successfull attempt of LMA were achieved in 93.3% and 90% of the patients respectively in group S (P<0.05). Myalgia and sore throat occurred in 66.7 % of patients in the group C in comparison with 33.3% in group S (P=0.06). CONCLUSION: The combination of propofol with mini dose succinylcholine, provided a significantly better method for LMA insertion, while reduced propofol doses were needed and number of attempts decreased.

Hemodynamic Stability during Induction of Anesthesia in ElderlyPatients: Propofol + Ketamine versus Propofol + Etomidate.

INTRODUCTION: Various methods have been recommended to prevent hemodynamic instability caused by propofol induction. Current study evaluates hemodynamic effects of ketamine and propofol in comparison to etomidate and propofol during anesthesia induction. METHODS: Sixty-two patients over 50 years old undergoing elective surgeries were randomly assigned to ketamine + propofol (ketofol) (n=30) and etomidate + propofol (etofol) (n=32) groups. Patients in ketofol group were induced with ketamine 0.75 mg/kg and propofol 1 mg/kg. In etofol group, induction was performed with etomidate 0.2 mg/kg and propofol 1 mg/kg. Hemodynamic states before and after induction, first, third and sixth minutes after intubation were measured and compared between groups. RESULTS: There was no difference between groups in systolic (SAP), diastolic (DAP) and mean arterial pressure (MAP), heart rate (HR) and blood oxygen saturation (SaO2). There was significant decrease in SAP, DAP and MAP after induction and 6 minutes after intubation and in HR after induction than values before induction. There was significant increase in SaO2 in all evaluated periods than before induction in etofol group; however, the difference in ketofol group was not significant. CONCLUSION: Both methods of induction -ketamine + propofol and etomidate + propofol- are effective in maintaining hemodynamic stability and preventing hemodynamic changes due to propofol administration.

Contributions of Medieval Islamic physicians to the history of tracheostomy.

Tracheostomy was first described by Greco-Roman physicians, including Paulus of Aegina. Medieval Islamic clinicians extended the Greco-Roman ideas with substantial contributions to the field of surgery, including tracheostomy. Although Al-Zahrawi (936-1013 CE) stated that he had not heard or read of any Islamic physicians having performed tracheostomy, there is evidence that many prominent Islamic surgeons did practice this lifesaving procedure during medieval times. Throughout the Islamic Golden Age, Muslim physicians advanced the practice of tracheostomy with many modifications of the procedure, instrumentation, and adjuvant medicinal prescriptions.

Warming Endotracheal Tube in Blind Nasotracheal Intubation throughout Maxillofacial Surgeries.

INTRODUCTION: Blind nasotracheal intubation is an intubation method without observation of glottis that is used when the orotracheal intubation is difficult or impossible. One of the methods to minimize trauma to the nasal cavity is to soften the endotracheal tube through warming. Our aim in this study was to evaluate endotracheal intubation using endotracheal tubes softened by hot water at 50 °C and to compare the patients in terms of success rate and complications. METHODS: 60 patients with ASA Class I and II scheduled to undergo elective jaw and mouth surgeries under general anesthesia were recruited. RESULTS: success rate for Blind nasotracheal intubation in the control group was 70% vs. 83.3% in the study group. Although the success rate in the study group was higher than the control group, this difference was not statistically significant. The most frequent position of nasotracheal intubation tube was tracheal followed by esophageal and anterior positions, respectively. CONCLUSION: In conclusion, our study showed that using an endotracheal tube softened by warm water could reduce the incidence and severity of epistaxis during blind nasotracheal intubation; however it could not facilitate blind nasotracheal intubation.

Effect of low level laser application at the end of surgery to reduce pain after tonsillectomy in adults.

INTRODUCTION: Tonsillectomy is among commonest otorhinolaryngologic surgeries. Many methods have been used to control post surgical pain, but despite it, pain is still one of the problems related to this operation. Recently, due to the non invasiveness of low level lasers, this modality has attracted attention. The purpose of this study is to evaluate the effects of low level laser irradiation at the end of surgery on reduction of pain after tonsillectomy in adults. METHODS: In a clinical trial, 60 adult patients, candidates for tonsillectomy were randomly assigned to two groups, A and B, and both groups were anesthetized similarly by the same technique. At the end of surgery, in the case group, the tonsils' bed were irradiated by infrared laser with 980nm wavelength, 100Hz, 4J/cm(2) from the infra mandibular angle. In the control group, the tonsils' bed had laser therapy with a turned off probe. Following laser treatment, the patients were reversed and extubated and consciousness achieved, pain and odynophagia were assessed at 2, 4, 6, 8, 12 and 24h post surgery based on visual analog scale for pain (VAS) and analgesic consumption. RESULTS: In the laser group frequency of patients with pain sensation in each evaluated hour was lower than in the control group. The amount of pain decrease and analgesic consumption reduction was significantly higher in patients who received laser (P=0.01). CONCLUSION: Based on the results of this study, use of low level lasers is effective in reducing tonsillectomy post surgical pain in adults.

A comparison of preoperative ondansetron and dexamethasone in the prevention of post-tympanoplasty nausea and vomiting.

BACKGROUND: Nausea and vomiting are common complications of anesthesia and surgery. Patients undergoing tympanoplasty are exposed to a higher risk of postoperative nausea vomiting (PONV). These complications may alter the results of reconstruction and anatomical alignments. Numerous antiemetics have been studied to prevent and treat PONV in patients undergoing tympanoplasty. The aim of this study was to compare the effect of intravenous ondansetron and dexamethasone on post-tympanoplasty PONV. METHODS: In a double-blind randomized controlled clinical trial, 219 patients were divided into three groups including one receiving ondansetron, one receiving dexamethazone, and one receiving distilled water. All patients were subjected to tympanoplasty type I. The patients in the first group received ondansetron (4 mg IV), second group received oexamethasone (8 mg IV), and third group received distilled water prior to induction of anesthesia. Using Bellivelle(')s scoring system, the incidence of PONV and its severity during the 24-hour period after surgery were measured and compared. RESULTS: There was no significant difference among PONV in the three groups in the first two hours after the surgery. However, in 2-8, 8-16 and 16-24 hours after the surgery the PONV in ondansetron and dexamethasone groups were significantly lower than that in the control group. CONCLUSION: Ondansetron and dexamethasone were more effective than placebo in controlling PONV after tympanoplasty surgeries. Moreover, dexamethasone was more effective than ondansetron in preventing PONV. TRIAL REGISTRATION NUMBER: IRCT201106154005N4.

Effect of low dose dopamine on early graft function in living unrelated kidney donors.

PURPOSE: To evaluate the effect of low-dose dopamine administration on the early function of the kidney in unrelated kidney donors after transplantation. MATERIALS AND METHODS: In this double-blinded clinical trial, 60 adult kidney donors and 60 recipients, younger than 50 years old, were studied. Donors and recipients were randomly divided into two groups; group 1 received dopamine 3 µ/kg/min and group 2 received similar regimen of placebo. During the first 3 days postoperatively, serum levels of urea and creatinine as well as urine output and early kidney function were compared between two groups. RESULTS: Serum levels of creatinine and urea and urine output during the first three days after the operation did not differ statistically significantly between two groups (P = .549, P = .306, and P = .375, respectively). Early kidney function was better significantly in group 1 (5.3 ± 3.2 versus 8.6 ± 8.0 hours; P = .048). CONCLUSION: Premedication of the kidney transplant donors with low-dose dopamine accelerates early kidney function after transplantation, but has no effect on the hemodynamic status and serum levels of creatinine and urea in the donors.

Administration of Remifentanil in Establishing a more Stable Post-anesthesia Cardiovascular Status in Neurosurgical Procedures.

INTRODUCTION: Emergence from general anesthesia and especially post-extubation phase are the stages associated with cardiovascular hyperdynamic status in which patients with increased intracranial pressure (ICP) could be affected by severe cardiac and or cerebral complications. Administering remifentanil could be helpful in maintaining the hemodynamic stability at the end of the surgery and recovery stages and reducing recovery phase length. METHODS: In a double-blind prospective randomized clinical trial, 60 adult patients with ASA (American Society of Anesthesiologist) class of I-II scheduled to undergo elective neurosurgery operations were randomly divided into two groups receiving remifentanil and placebo as IV infusion within four minutes prior to extubation continued by an IV infusion for 10 minutes after extubation. RESULTS: There was a significant difference between two groups regarding the changes of Mean Arterial Pressure after extubation and five minutes after extubation (P˂ 0.001).Remifentanil group compared with control group was of significant difference at all heart rate values after extubation (P< 0.001). CONCLUSION: Remifentanil could be used in preventing hyperdynamic status throughout extubation phase without extending recovery phase length. However, administration of this medication should be performed cautiously.

An Evaluation of the Effect of Morphine on Abdominal Pain and PeritonealIrritation Signs in Patients with Acute Surgical Abdomen.

INTRODUCTION: Acute surgical abdomen is one of the most common emergency surgical causes all over the world and also one of the most important abdominal pain causes which is sometimes intolerable for the patients referring to the emergency departments. Diagnosis and planning for operation in these cases is based on time-demanding serial examinations and results of paraclinical data. In this waiting period, patients have to tolerate pain.Therefore, we aimed to study the hypothesis that relieving pain has no influence on valuable findings in physical examination. METHODS: This double blind randomized clinical trial was carried out on 120 patients above 12 years old referred to an emergency department of a referral hospital with acute abdomen. Patients were divided into two groups of receiving intravenous placebo and Morphine randomly. Pain score, change in tenderness as well as change in rebound tenderness before and after receiving morphine or placebo were measured based on Numeric Pain Assessment Scale. RESULTS: Statistically significant difference was observed between both groups regarding the mean pain score. Prevalence of tenderness and rebound tenderness after medication administration revealed a significant difference between two groups. Furthermore, pain and tenderness showed a significant decrease in patients receiving morphine also a significant difference occurred in rebound tenderness between two groups. CONCLUSION: Despite the fact that opioid analgesics decrease pain in patients with acute surgical abdomen, they do not tend to eliminate required diagnostic data being obtained from physical examination like tenderness and rebound tenderness. Surprisingly, all the acute abdomen cases had rebound tenderness after morphine administration. Therefore, this research advises a cautious usage of morphine in patients with acute abdomen.

Multimodal preincisional premedication to prevent acute pain after cholecystectomy.

INTRODUCTION: Postoperative pain as an important medical concern is usually treated by opioids which also are of various inevitable side effects. The aim of this study was to assess the efficacy of multimodal preincisional premedication on preventing post-cholecystectomy acute pain. METHODS: In a randomized clinical trial, sixty patients undergoing open cholecystectomy were randomized into two groups. Before anesthesia induction, Diclofenac suppository (100 mg) and oral Clonidine (0.2 mg) were administered in the first group. Immediately before operation, patients received Ketamine (1 mg/kg IV) while the control group received placebo. The site of incision was infiltrated by the surgeon with 20 mL Bupivacaine 0.25% in both groups. Anesthesia induction and maintenance were similar in both groups. The severity of pain was recorded 2, 4, 6, 12, 24 and 48 hours after operation according to Visual Analogue Scale. RESULTS: The severity of pain at two defined stages (6 and 12 hours later) was significantly less in the intervention group than the control group (P<0.005). The average pain severity score was less than the control group (P<0.005). CONCLUSION: In our study, the administration of Clonidine, Diclofenac and Ketamine and bupivacaine infiltration to the site of incision, altogether was associated with a significant decrease in pain score and opioid requirement after cholecystectomy in comparison to bupivacaine infiltration to the site of incision.

Esmolol: a unique Beta-blocker in maintaining cardiovascular stability following neurosurgical procedures.

PURPOSE: Patients with increased intracranial pressure (ICP) are prone to severe cardiac and or cerebral complications following emergence from general anesthesia and especially post-extubation phase. Administering beta blockers including esmolol is believed to be helpful in providing a stable hemodynamic at the end of the surgery and recovery stages and reducing recovery phase length. METHOD: In a double-blind prospective randomized clinical trial, 60 adult patients with ASA (American Society of Anesthesiologist) class of I-II scheduled to undergo elective neurosurgery operations were randomly divided into two groups receiving esmolol (n=30) and placebo (n=30) as IV infusion within four minutes prior to extubation continued by an IV infusion for 10 minutes after extubation. RESULT: There was a significant difference between two groups regarding the changes of systolic blood pressure and heart rate at all studied stages after extubation (P≤0.05). However, no significant difference existed between esmolol and control groups regarding recovery and extubation times emphasizing the fact that esmolol is of excellent early recovery and extubation profiles. CONCLUSION: Esmolol is advised to be used in preventing hyperdynamic status throughout extubation phase without extending recovery phase length.

Comparison thoracic epidural and intercostal block to improve ventilation parameters and reduce pain in patients with multiple rib fractures.

INTRODUCTION: Chest wall blunt trauma causes multiple rib fractures and will often be associated with significant pain and may compromise ventilator mechanics. Analgesia has great roll in rib fracture therapies, opioid are useful, but when used as sole agent may require such high dose that they produce respiratory depression, especially in elderly .the best analgesia for a severe chest wall injury is a continuous epidural infusion of local anesthetic. This provides complete analgesia allowing inspiration and coughing without of the risk of respiratory depression. METHODS: sixty adult patients who with multiple rib fractures were enrolled in this study. They were divided into Group A or thoracic epidural with bupivacaine 0.125 % +1mg/5ml morphine and group B or intercostal block with 0.25% bupivacaine. The patients were assessed through ICU and hospital stay length, ventilation function tests. Pain score among the patients was measured with verbal rating scale, before and after administration of the analgesia. RESULTS: We found a significant improvement in ventilatory function tests during the 1st, 2nd, and 3rd days after epidural analgesia compared with the intercostal block (P < 0.004). Changes in the visual Analogue Scale were associated with marked improvement regarding pain at rest and pain caused by coughing and deep breathing in group A compared group B... ICU and hospital stay markedly reduced in Group A. CONCLUSION: thoracic epidural analgesia is superior to intercostals block regarding pain relief of rib fractures. Patients who received epidural analgesia had significantly lower pain scores at all studied times.