JOURNAL OF IRANIAN SOCIETY ANAESTHESIOLOGY AND INTENSIVE CARE
Year:2004 | Volume:25 | Issue:45|Papers Count:13

The stress response is the name given to the hormonal and metabolic changes which follow injury or trauma. This is part of the systemic reaction to injury which encompasses a wide range of endocrinological, immunological and hematological effect. The endocrine response is activated by afferent neuronal impulses from the site of injury. These travel along sensory nerve roots through the dorsal root of the spinal cord, up the spinal cord to the medullae to activate the hypothalamus. The efferent responses to the liver and the medullae, the endocrine response of the hypothalamus and the activation of the sympathetic system results in the release of ACTH, GH, vasopressin, cortisol and inhibition of insulin release. The metabolic results of this response are increased serum glucose (hyperglycemic response), increased gluconeogenesis in the liver, activation of lipolysis, degradation of proteins and insulin resistance in the cells. Although it seems that the stress response developed to allow injured animals to survive by catabolizing their own stored body fuels, it has been argued that the stress response is unnecessary in current surgical practice. Strenuous efforts have been made to inhibit the stress responses to surgery with respect to the potential beneficial effects on surgical outcome and thoracic epidural analgesia is one of the most promising methods. In this regard the objective of this study is to evaluate the effect of thoracic epidural analgesia on stress response and measuring the serum glucose is an index of hyperglycemic response in our study. This study was designed as a randomized controlled trial. Twenty nine patients undergoing elective nephrectomy or nephrolithiasis surgery were studied to compare the effects of thoracic epidural anesthesia and general anesthesia on plasma glucose before and during the surgery. patients received either a thoracic epidural anesthesia (TI-L2) with general anesthesia (TEA+GA) or general anesthesia alone (GA). Glucose levels were measured before and one hour after induction of anesthesia and hemodynamic variables were measured before and every 5 minutes during the surgery.Patients qualified entering the study (29 patients) had a mean age of 33.3 years (SD = 7.7yr). 15 patients were allocated to the GA group and 14 patients to the TEA+GA group. There were no differences regarding the basic variables measured mentioned earlier between these groups, but the glucose level were significantly lower in the TEA +GA patients. i It seems that TEA effectively inhibited the hyperglycemic response to surgery and it is suggested that this effect is 1 mediated by inhibiting the afferent and efferent impulses at the level of the spinal cord. However further studies evaluating I this technique in other surgery types and patients with metabolic or endocrine diseases are suggested.

Intravenous regional anesthesia (IVRA) is a technique for providing anesthesia during extremity surgery. Lidocaine is one of local anesthetics which commonly used for IVRA. Pethidine (meperidine) has been shown to have weak local anesthetic properties. The aim of this study was to evaluate whether pethidine alone, compared to lid6caine, produce sufficient anesthesia during intravenous regional anesthesia.50 ASA I-II adult patients undergoing orthopedic surgery for upper extremity received IVRA under double tourniquet condition with either pethidine or lidocaine. Patients were randomly assigned to one of two groups: P group received 40ml and L group received 40ml 0.5% lidocaine. Onset of sensory and motor block, sensory and motor block recovery times, pain score after tourniquet released, total midazolam and sufentanil doses during surgery and recovery room, and incidnece of adverse effects were recorded.Onset of sensory and motor block in P group was slower than L group. Sensory block recovery time was more prolonged in P than L group, but not significant difference in motor block recovery time. Average doses of sufentanil and midazolam administrated during surgery in P and L groups were no significant differences, but sufentanil administrated during recovery room was lower in P than L group. Pain score at first 30 min after tourniquet released in P group was lower than L group. Some side effects was more in P group and some was more in L group.Our study showed that the pethidine as sole anesthetic in IVRA can not be first choice drug, but when lidocaine be contraindicated, pethidine can be alternative drug and produce acceptable anesthetic condition.

Mechanical ventilation is one of the most important life sustaining interventions in medicine. Morbidity and mortality in patients who received mechanical ventilation have been studied in different patient groups. We undertook this study to examine the patterns of mortality in mechanically ventilated patients at our intensive care unit.In this retrospective analysis the medical records of 173 patients who underwent mechanical ventilation between 1380-1381 SY at the general lCU of a large tertiary referral center were reviewed systematically. Patients demographics, underlying disease, reason for mechanical ventilation, time to mechanical ventilation and outcome data available in the charts were collected for analysis.The mean age of the patients was 50.4± 23 years and 98 (56.6%) were male. The commonest indication for initiation of mechanical ventilation was inadequate mental status to protect airway in patients with multiple trauma and head injury in 76 (46.6%) patients. ICU mortality occurred in 120 (70%) patients. Mortality had significant correlation with age (53.6± 22.7 years vs. 42.2± 22.7 years, p=0.018).Mortality of the ventilated patients has direct and significant correlation with age. The mortality of 70% observed in our lCU patients who underwent mechanical ventilation during the above time period could be attributed to the following reason; 1) The lCU where this study was carried out was an open general lCU where the care was delivered by the admitting teams with insufficient critical care training, 2) Poor proportion of lCU beds in relation with total hospital beds in a tertiary teaching medical center, 3) Patients who got mechanically ventilated due to airway compromise and coma secondary to multiple trauma and head injury with poor prognosis, constituted the main bulk the study population.Future studies are needed when such units are managed in a closed fashion with the care delivery by trained intensivists and improved lCU to hospital bed ratio with resultant decrease in the selection bias.

Nosocomial infections can elongate the duration of admission and increased mortality rate. The study and comparison of common microbial infection in ICU will lead to decrease the financial load of hospitals. The poisoning center ICU in Loghman Hospital is the sole poisoning center in Tehran, so the study and comparison of infection between toxic ICU and general ICU, advocate noticeable information.The survey had conducted in descriptive, cross sectional method. We gathered 46 site samples in each of the two ICU'S. The samples extracted in a random order from environment and instruments of ICU. We examined 3 times (every 45 days, one sample gathering). The samples were placed in Stewart media, then inoculated into McConkey and blood agar media. Colony count greater than 5 considered significant.The rate of infection was 83% in toxic center and 96% in general ICU. That respectively 44% and 52% was gram negative. Coagulase positive staph, acinetobacter, bacillus and pseudomonas were the most prevalent organisms. According to this survey the rate of infection in general ICU was not significantly greater than the other one. But variety of microorganisms was higher in toxic center ICU. In this study we found that pattern of resistance to Ceftazidim is very high and using of Ciprofloxacin could be a good alternative. Continuous study of microbial surveillance, microbial infection and anti-microbial resistant pattern in ICU, seems necessary.

Spinal anesthesia has numerous indications in lower abdomen and limbs surgery, but duration of analgesia and anesthesia is one of the limitation of this method. Lidocaine - the most common drug in spinal anesthesia causes a short term anesthesia and analgesia which is lower than one hour.Today different kinds of drugs are used for enhancing onset, increasing intensity and analgesia duration in spinal anesthesia such as magnesium sulfate which it blocks NMDA receptors. In a randomized double blind c1incial trial study, 80 patients candidate for elective ortopedic surgery in Sina Hospital were divided into two groups. In control group 2mllidocaine 5%+0.5ml sterile water was injected and in the other group 2ml lidocaine 5% +0.5cc magnesium sulfate 10% - without preservative - was injected. The patients were immediately tilted to head up position (15)o.Level of sensory block was evaluated by pin-prick test in midc1avicular line. Analgesic duration was considered from the time of injection until the patient's asking for analgesic or complaining of pain. Anesthesia level was T10-T12 in most patients. Minimum level was T12 an Maximum level was T6 in both groups. The mean analgesic duration was 129± 53.5 min in case group and 67± 36.5 min in control group that is statistically significant (p=0.001). Analgesic duration in case group was between 60 and 240 min and in control group was between 15 min and 150min. In conc1ution, when MgS04 is added to lidocaine in spinal anesthesia, the duration of analgesia is increased significantly. This increase of duration of analgesia was not accompanied by increase of side effects.

To determine and compare the prophylactic effects of i.v. dexamethasone 8mg with metoclopramide in preventing nausea and vomiting during intrathecal injection of meperidine for postoperative analgesia.In a randomized, double-blinded, placebo-controlled study, 105 ASA physical status I or II men ranging 18-40 years underwent elective lower limb orthopedic surgery receiving spinal anesthesia with 75mg lidocaine 5% and 15mg meperidine for postoperative analgesia, were enrolled. Patients were randomly allocated to normal saline (2ml saline, iv), methoc1opramide (2ml equal to 10mg, iv) and dexamethasone (2ml equal to 8mg dexamethasone, iv) groups and received their medications just before surgery. The incidence of PONV and side effects were evaluated during surgery, recovery period, 6 and 24hr after spinal anesthesia.The differences between demographic and hemodynamic variables, infused ringer duration of surgery, highest level of anesthesia, and number of patients requiring rescue antiemetics and analgesics and postoperative pain intensity were not significant. Patients who received dexmethasone and metoc1opramide, have significantly lower incidence of nausea and vomiting compared who received saline in recovery period, 6 and 24hr after spinal anesthesia (p<0.05). The incidence of nausea in 6 and 24 hr and the incidence of vomiting in 24hr after spinal anesthesia were significantly lower in dexamethasone compared with metoc1opramide (p<0.05).Dexamethasone, 8mg i.v., is suggested in preventing nausea and vomiting associated with intrathecal injection of meperidine for postoperative analgesia.

Anesthesiology as a medical speciality had its beginning early in the century when physicians began to manage vital functions during surgery in addition to simply performing the surgical preequisites of inducing unconsciousness and wakening patients at the end of surgery. Complex surgery performed on sicker patients become increasingly possible as physician - anesthetists developed techniques for critical care and active preoperative management of vital functions the general public understood little of these developments. We tried to evaluate patients's knowledge about Anesthesia and responsibilities of anesthesiologists and determine effects of several factors on it. We studied 400 patients who refered to anesthesia clinic for preoperative assessment in Sina Hospital from October 2003 till March 2004.We asked the patients to fill out our questionnair before preoperative evaluation. The mean age of our patients was 40.2 years with standard deviation of 15.2 Mean knowledge of them about anesthesia was 43.3 with standard deviation of 21.There was no correlation between patient's knowlege about anesthesia and factors such as age, sex, prior anesthetic experience and fear, but there was direct correlation between patient's knowledge about anesthesia and education, job, willingness to preoperative evaluation by physician, cause of fear, willingness to spinal anesthesia and confidence in physicain (p<0.001).Thus we found strong correlation between patient's knowledge about anesthesia and their confidence in physician or cooperation for regional anesthesia.

Rib fracture is a frequent complication of chest trauma that results in pain and pulmonary dysfunction.Pain intensity and pulmonary dysfunction occasionally require respiratory support. Since rib fracture does not usually require surgical intervention, using various pain management methods including nerve block reduces pain and improves pulmonary function. In a single blind clinical trial study we studied the effect of interpleural block on pain reduction in patients with rib fracture.46 patients with unilateral fracture of more than two ribs in the range of 20-50 years entered the study. The patients received 2mg/kg of pethidine after increasing the volume to 20ml. The procedures was repeated every 8 hours for 48 hours. Pain intensity was evaluated with NRS (numeric rating scale) and morphine PCA requirement.46 patients, 26 males and 20 females, with unilateral rib fractures were studied. The average age of the patients was 32.76 years.Pain intensity reduced in all the patients using NRS. NRS reduced from 4.48 before block to 1.90 after block.Morphine PCA requirement were 20.21mg and 16.63mg in the first and second days, respectively.Both intercostal block with bupivacaine and interpleural block with pethidine could reduce pain in rib fracture. pain reduction was more significant in the interpleural block group.Considering the efficacy of interpleural block with pethidine to reduce pain and to improve pulmonary function in rib fracture and less side effects of pethidine in comparison to other local anesthetics, pethidine can be used for interpleural block instead of other local anesthetics.

Although esophageal due to transesophageal echocardiography (TEE) is rare, it is a serious complication. In this presentation two cases of perforation due to TEE are reported. The outcome of the patients depend on the early diagnosis and the correct of management of the probe.