comparability of second dose thiopental with lidocaine in the attenuation of cardiovascular reponse to endotracheal intubation

This study was carried out to appraise the usefulness of second dose thiopental for hemodynamic response to laryngoscopy and intubation. The present study comprised 120 patients aged 15 to 65 years who were divided into four groups each of 30 patients. Patients in each group were given 2 microg/kg fentanyl IV, 4 mg/kg thiopental for induction of anesthesia, followed by 0.5 mg/kg atracurium for muscle relaxation and a second dose of thiopental [1mg/kg in group I, 2mg/kg in group II] immediately prior to laryngoscopy and intubation, lidocaine 1.5 mg/kg [group III] or normal saline 5 ml [group IV] 2 minutes prior to larygoscopy and intubation. The heart rate [HR], systolic arterial pressure [SAP], diastolic arterial pressure [DAP], mean arterial pressure [MAP], and rate pressure product [RPP] were determined before induction of anaesthesia and laryngoscopy [baseline], and at 1min [T1], 3min [T3], 5min [T5], and 10min [T10] after laryngoscopy and intubation. Our findings demonstrated similar effects of lidocaine and second dose thiopental 2mg/kg on attenuation of DAP, MAP, RPP, and HR changes at 1, 3, and 5 min after endotracheal intubation [EI]. Second dose thiopental can be employed as a substitute for lidocaine in attenuation of cardiovascular response to intubation in patients devoid of ischemic heart disease

Association between admission hypomagnesemia mortality or mortality of critically ill patients in intensive care unit

Up to now there is no study evaluating correlation between serum magnesium and morbidity or mortality in patients admitted in intensive care unit. The aim of this study is to determine the prevalence of hypomagnesemia in critically ill patients and to evaluate its association with organ dysfunction, hospitalization period and mortality. We conducted a retrospective trial including 100 patients aged 16 years and above admitted to the medico-surgical intensive care unit over 2 years. Firstly, total serum magnesium was determined and then is correlation with ventilator need, duration of mechanical ventilation, hospitalization period, and demographic characteristics were evaluated. At the time of admission, 51% and 49% of the patients showed hypomagnesia and normomagnesia, respectively. Significant difference was observed in mortality rate, hospitalization period, or hospitalization in intensive care unit between the two groups [P<0.05, each]. Hypocalcemia, hypokalemia, and hypmonatremia were frequently observed in hypomagnesemic patients, The patients with hympomagnesemia in intensive care unit demonstrated higher Acute Physiology And Chronic Health Evaluation II [APACHE-2] and Sequential Organ Failure Assessment [SOFA] scores at time of admission [P<0.01], a higher maximum SOFA score during hospitalization in intensive care unit, higher requirement to ventilator, and longer duration to mechanical ventilation than the other patients. The ROC curve of SOFA score in the hypomagnesemia generated significant results compared to APACHE-2. An increase of 5 units in the APACHE-2 or SOFA measured during admission increased relative probability of hypomagnesemia by 0.12 and 0.16, respectively. Hypomagnesemia during hospitalization in intensive care unit was associated with a poor prognosis. Monitoring of serum magnesium may have prognostic and therapeutic implications

[ cardiovascular effects of inspired oxygen fraction in patients undergoing on-pump coronary artery surgery]

Increased inspired oxygen fraction [Fio[2]] has significant negative hemodynamic effects in conscious volunteers. The aspiratory gas during open heart surgery with on-pump technique usually consists of 100% oxygen without any N[2]O because of the risks of bubble embolism during these procedures. We sought to establish the effect of inspired pure oxygen in comparison to 50% oxygen in patients. During anesthesia in cardiac coronary bypass surgery. In a clinical trial study, sixty adult patients [40-70 y/o] with ASA II or III undergoing elective on-pump coronary artery bypass were elected. They received either a mixture of 50% O[2] with 50% air [case group=30] or 100% of oxygen [control group=30] throughout the anesthesia. Cardiac index [CI] was measured by non invasive cardiac output [NICO] technique using end tidal PCO[2]. Measurements of systolic, diastolic and mean blood pressure as well as heart rate [HR] and central venous pressure [CVP], PaO[2], arterial PH and CI were obtained at pre-bypass, post bypass, end of surgery and 2 hours after ICU admission. Intra operative requirements for isotropic drugs were also evaluated. Data were analyzed by SPSS software using X2, t, ANOVA and Man Withny tests, P<0.05 was considered as significant. No differences were found between the two groups with regard to age, sex pump time, operation time and body mass index and preoperative ejection fraction [EF]. The mean values of systolic, diastolic and mean blood pressure as well as HR and CI were similar in the case and control groups [P>0.05] at all times of measurement. The control group required more isotropic drug support than the case group [16 vs. 8 patients respectively; P<0.05]. Likewise, the mean CVP was higher in the control group compared with the case group [P<0.05]. Hyperoxia increases CVP and isotropic requirements during cardiac surgery in anaesthetized patients. Therefore, exposing patients during and after coronary artery surgery to hyperoxia induces significant hemodynamic change as which require more extensive studies with invasive CI measurements and larger groups

[ impact of hyperglycemia or hypoalbuminemia on duration and need to mechanical ventilation in critically ill patients]

In addition to lung mechanics measurements, many physiological factors also have impact on weaning of critically ill patients, but are often overlooked. Hyperglycemia is common in critically ill patients. The purpose of this study was to assess the utility of hypoalbuminaemia or hyperglycemia as predictors for need ventilator and weaning success in critically ill patients. A single center, descriptive- analytical trial was done on 600 patient's >= 16 years old admitted for 3 or more days to intensive care unit. Patients were classified into five different groups based on the cause of respiratory failure. The following parameters were recorded: serum albumin and glucose concentration; Acute Physiology and Chronic Health Evaluation III score; need ventilator, ventilation days, and fluid balance. The initial mean serum glucose concentration was 9.3 +/- 0.2 mmol/l and the initial mean serum albumin concentration was 30.2 +/- 0.02 [0.2 g/dl] g/l. Although the circulating albumin concentration was significantly lower and serum glucose concentration was significantly higher in ICU nonsurvivors than in ICU survivors, albumin [r=-0.031, P>0.05] and blood glucose concentration [r=0.050, P>0.01] on ICU admission were not a predictor of the length of time spent receiving mechanical ventilation. Patients with serum albumin concentration less than 30.3 [3.03 g/dl] g/l were one and two tenth times more likely to need ventilator than normoalbuminemic patients [relative risk 1.2, 95% confidence interval 1.06 to 1.31]. The risk of need to mechanical ventilation did not raise with blood glucose concentration more than 11 mmol/l [200 mg/dl]. These findings suggest that albumin or blood glucose may be an index of the metabolic status of the patient, which could be important in determining the need ventilator and wean ability of the patients who are mechanically ventilated for prolonged periods of time

[Prediction of difficult laryngoscopy in the patients undergone cesarean section]

Unsuccessful intubations is important cause of anesthetic-related maternal mortality. Therefore, the purpose of this study was to determine the ability to predict difficult visualization of the larynx [DVL] from the following preoperative airway predictive indices: modified Mallampati test [MMT], the ratio of height to thyromental distance [RHTMD], and the upper- Lip-Bite test [ULBT]. This prospective and double-blind study was conducted on the patients undergone elective cesarean section under general anesthesia requiring endotracheal intubations. RHTMD, MMT and ULBT tests were used for them prior to the operation. An experienced anesthesiologist, not apprised of the recorded preoperative airway assessment, performed the laryngoscopy and grading [as per Cormack and Lehane's classification]. Then, sensitivity, specificity, positive and negative predictive value, and false negative value for each airway predictor in isolation and in combination were determined. T and Mann Whitney tests were used for comparing of demographic data and comparing among the tests, respectively. Difficult laryngoscopy [Grade 3 or 4] was observed in 35 patients [8.75%]. RHTMD had a higher sensitivity, positive predictive value, and fewer false negatives than the other variables tested. A RHTMD=21.24 provided the best cutoff point for predicting subsequent difficult laryngoscopy. The odds ratio [95% confidence interval] of the RHTMD, Mallampati class, and ULBT were 7.8 [1.21-21.21], 2.1 [1.11-5.60], and 1.5 [0.6-4.1], respectively. The RHTMD may prove a useful screening test for predicting difficult laryngoscopy in obstetric population

[ comparison of beclomethasone inhaler and intravenous lidocaine in prevention of postoperative airway and throat complaints]

Tracheal intubation can result in trauma and nerve damage which may also account for postoperative throat symptoms such as hoarseness and dysphagia. The effects of beclomethasone inhaler and intravenous lidocaine in prevention of the above symptoms were documented in previous studies. The aim of the present study is comparison of the effects of beclomethasone inhaler with various clinically used dosages of intravenous lidocaine prior to endotracheal intubation on the incidence and severity of postoperative sore throat, cough, sputum, hoarseness, and dysphagia. A total of 120 patients undergoing elective operations were enrolled in this randomized double-blind clinical trial. Patients were assigned to one of four treatment modalities: lidocaine 1mg/kg [group L[1]], lidocaine 1.5 mg/kg [group L[2]], a dose of 50 micrograms beclomethasone inhaler [Group B], and normal saline [Group C]. Incidence and severity of sore throat, cough, sputum, hoarseness, and dysphagia were compared between the groups before leaving the operating room, 1 hr later, at the time of the first postoperative drink or meal [for assessment of dysphagia], and in the morning after the surgery. In all time intervals of evaluating postoperative symptoms, the incidence and severity of sore throat were significantly lower in groups L2 and B than in group C [P <0.05]. One and twenty hours after emergence of anesthesia, the incidence and severity of cough were significantly lower in groups L[2] and B than in group C [P <0.05]. The incidence and severity of sore throat or cough was not significantly different between groups L2 and B. Throughout the study, the incidence and severity of sputum were significantly lower in group B than in group C [P <0.05]. Beclomehtasone in comparison with intravenous lidocaine prior to intubation decreases the postoperative sore throat and cough. In addition, beclomethasone inhaler decreases the incidence and severity of postoperative sputum

cardiovascular changes induced by inspired oxygen fraction in patients undergoing on-pump coronay artery surgery

The inspiratory gas during open heart surgery with on-pump technique usually consists of 100% oxygen without any N2O because the risks of bubble embolism during these procedures. We sought to establish whether the cardiovascular effects of increased FiO2 are also present in cardiac surgery patients. The present study was a randomized double- blind clinical trial on sixty adult patients [40-70 years] with the cardiac ejection fraction [EF] of more than 40% and ASA II or III undergoing elective on pump coronary artery bypass. They received either a mixture of 50% O2 with 50% air [case group=30] or 100% oxygen [control group=30] throughout the anesthesia. Data were analyzed by SPSS software using t-test and Q-square as well as non parametric tests wherever appropriate. The mean values of systolic, diastolic and mean blood pressure as well as HR and CI were similar in the case and control groups [p>0.05] at all times of measurement. The mean PaO2 was significantly higher in the control group [p<0.05]. The mean pH was statistically higher in the control group but not clinically noticeable. The control group required more inotropic drug support than the case group [16 vs. 8 patients respectively]. Likewise, the mean venous pressure was higher in the control group compared with the case group. Exposing patients during and after coronary artery surgery to hyperoxia induced significant hemodynamic changes which required more extensive studies with invasive CI measurements and larger groups

Influence of head flexion on intraocular pressure, cardiovascular, and respiratory responses in patients undergoing cataract surgery after endotracheal intubation

In cataract surgery, the periorbital area is prepared and draped after induction of general anesthesia and endotracheal intubation [ETI]. For this purpose, the patient's head and neck is usually flexed 30 to 45 degrees. Neck flexion causes displacement of the endotracheal tube tip toward the carina. Stimulation of the tracheal mucosa may cause bucking, increased intraocular pressure [IOP], laryngospasm and/or bronchospasm, during light anesthesia. Laryngeal constriction and all components of the tracheal response may affect end-tidal carbon dioxide pressure [PETCO2] and peripheral arterial hemoglobin oxygen saturation [SpaO2]. Thus, in the current study, we investigated the influence of head and neck flexion on heart rate [HR], systolic and diastolic blood pressure [SAP and DAP], SpaO2, PETCO2, and IOP in patients undergoing cataract surgery with endotracheal intubation during general anesthesia. The present prospective study comprised patients aged from 40 to 80 year with 106 American Society of Anesthesia [ASA] physical status I and II. Anesthesia was induced with thiopental sodium, lidocaine and fentanyl. Atracurium 0.5 mg/kg was administered to facilitate tracheal intubation. HR, SAP, DAP, SpaO2, PETCO2, and IOP were measured at 1, 2, and 5 minutes after head flexion. Mean SAP, DAP, IOP, and HR was increased after ETI and head flexion compared with baseline values. PETCO2 and SpaO2 were decreased after ETI and at 1, 2 minutes after head flexion compared with baseline values. In patients undergoing cataract surgery during general anesthesia, endotracheal tube movement caused changes in head and neck position resulting in significant effects on heart rate, systolic and diastolic blood pressures, laryngeal reflexes, SpaO2, PETCO2, and intraocular pressure

Comparative effects of different anesthetic regimens on the oculocardiac reflex

The oculocardiac reflex [OCR], which is most often encountered during strabismus surgery in children, may cause bradycardia, arrhythmias, and cardiac arrest following a variety of stimuli arising in or near the eyeball. The main purpose of this study was to evaluate the effects of various anesthetic regimens on modulation of the cardiovascular response of the OCR during strabismus surgery. Three hundred American Society of Anesthesia [ASA] physical status I-II patients, scheduled for elective strabismus surgery under general anesthesia, randomly allocated in a double blind fashion to one of three anesthetic regimens of group P [propofol 2 mg/kg, alfentanil 0.02 mg/kg, and atracurium 0.5 mg/kg at induction], group K [ketamine racemate 2mg/kg, alfentanil 0.02 mg/kg, and atracurium 0.5 mg/kg at induction] and group T [thiopental 5mg/kg, alfentanil 0.02 mg/kg, and atracurium 0.5 mg/kg at induction. Mean arterial pressure [MAP] and heart rate [HR] were recorded just before and at 1, 15, 30, 45, and 60 min after induction. OCR was defined as a 20 beats/min change in HR induced by traction compared with basal value. Mean heart rate [ +/- SD] during the course of surgery in group P was significantly slower than in the K group [111.90 +/- 1.10 vs. 116.7 +/- 0.70 respectively, P < 0.05] .Mean HR changes [ +/- SD] in group K was significantly higher than in P group [11.2 +/- 1.44 vs. 8.7 +/- 1.50 respectively, P < 0.05]. Mean arterial pressure changes [ +/- SD] were significantly lower in group P than in group K or T patients [12.5 +/- 1.13 vs. 19.3 +/- 0.80 or 18.9 +/- 0.91 respectively, P < 0.05]. Frequency of OCR was significantly lower in group K than group T or P patients [9% vs. 16% or 13% respectively, P < 0.05]. Induction of anesthesia with ketamine is associated with least cardiovascular changes induced by OCR during strabismus surgery

Modified index of orthodontic treatment needs [IOTN] assessment by senior dental students

Rater's reliability is an important issue in index calculation. The purpose of this study was to evaluate the intra-examiner agreement in identification of orthodontic treatment needs using modified IOTN. In this analytical cross-section study, six senior dental students identified IOTN on 42 dental casts by means of a standard DHC ruler with a two-week time lag. The kappa and association models were used to analyze the data. The kappa statistics showed intra-rater agreements between 0.54 and 0.77 [ +/- 0.65], which can be considered as [good]. About 33% of the students had problems in distinguishing the first and second levels of the index, while there were fewer problems in distinguishing between the second and third levels. The category identification with most problems was the distinction between the first and second levels [0.48], and the one with the least problem was that of the second and third levels [0.99]. The distinction of the first and second levels in modified IOTN is hard for the examiners. Therefore, this issue should be considered in calibration training programs when using this index in screening, survey or epidemiological evaluations

[ effect of head flexion after endotracheal intubation on intraocular pressure, cardiovascular, and respiratory responses in patients undergoing cataract surgery]

During the cataract surgery, after induction of general anesthesia and endotracheal intubation [ETI], the periorbital area is prepared and draped. For this purpose, the patient's head and neck is usually flexed 30 to 45 degrees. Neck flexion causes displacement of the endotracheal tube tip toward the carina. Stimulation of the tracheal mucosa especially during light anesthesia may cause bucking, increase in intraocular pressure [IOP], laryngospasm and/or bronchospasm. Laryngeal constriction and all of the components of the tracheal response may have some effects on end-tidal carbon dioxide pressure [PETCO[2]] and peripheral arterial hemoglobin oxygen saturation [SpaO[2]]. In the current study, the influence of head and neck flexion after endotracheal intubation on the patients' heart rate [HR], systolic and diastolic blood pressure [SAP and DAP], SpaO[2], PETCO[2], and IOP was investigated for patients, who underwent cataract surgery during general anesthesia. In a double-blind clinical trial study, 106 patients aged 40-80 years were included according to ASA [American Social Anesthesia] physical status I and II. Anesthesia was induced with sodium thiopental, lidocaine and fentanyl. Atracurium 0.5 mg/kg was given to facilitate tracheal intubation. HR, SAP, DAP, SpaO[2], PETCO[2], and IOP were measured at 1, 2, and 5 minutes after head flexion. Data were then analyzed using Chi-Square and t-test, p< 0.05 was considered as significant. The means of SAP, DAP, IOP, and HR were increased after ETI, head flexion [p<0.05] and PETCO[2], SpaO[2] were decreased after ETI, also after 1 and 2 minutes head flexion compared with the baseline values [p<0.05]. It can be concluded from this study that for patients undergoing cataract surgery during general anesthesia, endotracheal tube movement along with changes in head and neck position may have a significant effect on heart rate, systolic and diastolic blood pressures, laryngeal reflexes, SpaO[2], PETCO[2], and intraocular pressure. Accordingly, an adequate monitoring of these vital parameters during anesthesia is warranted

[ effects of sufentanil or remifentanil pretreatment on propofol injection pain]

Propofol produces anesthesia with rapid recovery. However, it causes pain or discomfort during injection. The effect of remifentanil in prevention of propofol-induced injection pain was demonstrated in earlier studies. Sufentanil, an opioid analgesic, has not been studied for managing pain on injection of propofol. We have compared the efficacy of remifentanil and sufentanil for the prevention of propofol induced pain. One hundred twenty American Society of Anesthesiologists [ASA] class I-II adults undergoing elective surgery were randomly assigned into four groups of 20 each. Patients received 2 mL [10 mircro g] sufentanil, 2 mL of remifentanil [10 micro g], 2 mL of remifentanil [20 micro g], or 2 mL of saline 60 seconds prior to administering 5 mL of propofol 1%. Patients were asked whether they had pain due to propofol injection.Their pain scores were evaluated with the use of the four-point scale of Ambesh. The remifentanil and sufentanil groups significantly showed lower frequency of pain than that in the saline group [p < 0.05]. Median pain intensity scores were significantly lower in the group receiving remifentanil 20 micro g compared with the sufentanil groups [P < 0.05]. The median intensity of propofol-induced pain was statistically similar between the groups receiving sufentanil or remifentanil 10 g and the placebo groups. Remifentanil 20 micro g over 1 min before propofol administration is more effective than sufentanil 10 micro g 1 min prior to propofol in reducing the incidence and intensity of injection pain

Effects of preoperative sub-tenon block on intra- and post-operative complications in retinal detachment surgery

To evaluate the efficacy of sub-tenon block [preemptive analgesia] following general anesthesia and before the beginning of scleral buckling and cryopexy in retinal detachment [RD] surgery on decreasing intra- and post-operative complications. Sixty eight patients scheduled for RD surgical repair with ASA [American Society of Anesthesiologists] class I or II were enrolled in this clinical trial. The patients were randomly divided into two groups. Both groups underwent general anesthesia [GA], but one group received sub-tenon block as preemptive analgesia following induction of general anesthesia [treatment group]. Intra- and post-operative [up to 24 hours] incidence of oculocardiac reflex [OCR], mean blood pressure [BP], heart rate [HR], post-operative ischemic heart disease [IHD] changes, nausea and vomiting [PONV], delirium, total analgesic consumption, severity of ocular pain, frequency of analgesic requirement, and duration of hospitalization were compared between the two groups. There was no statistically significant difference between the two groups regarding age, sex, and preoperative blood pressure [BP] and heart rate. Mean BP of patients in the treatment group and the control group was 126.6/74.8 and 126.4/74.4 mmHg, preoperatively [P>0.2] and 12 6.4/76.4 and 134.6/74.4 mmHg, postoperatively [P=0.01]. Pain complaint of any degree was more frequent in the control group such that 38% in the recovery room and 25% 6 hours after surgery complained of severe pain compared to none in the treatment group. [P= 0.001] Incidence of delirium in the recovery room was 3.7% in the treatment group vs. 24.1% in the control group. [P= 0.001] Mean duration of hospitalization after surgery was 26.6 +/- 1.5 hr in the treatment group and 34.0 +/- 1.5 hr in the control group. [P<0.01]. Sub-tenon block following induction of CA for RD surgery reduces intra- and post-operative complications effectively, therefore it is recommended for routine ophthalmologic procedures