Magnesium sulphate as a technique of hypotensive anaesthesia for endoscopic sinus surgery

This randomized, doable-blind, placebo-controlled study was designed to assess the homodynamic effects of administered i.v magnesium [Mg] sulphate as a technique of hypotensive anaesthesia as well as its effect on duration of surgery, operative field visibility and the amount of blood loss during functional endoscopic sinus surgery [FESS]. Forty patients undergoing functioned endoscopic sinus surgery [FESS] for grade III and/or grade Iv pathology unresponsive to medical treatment were included in two parallel groups, the [Mg] sulphate group twenty patients received magnesium sulphate 40 mg kg[-1] i.v as a bolus before induction of anaesthesia and 15mg kg[-1] h[-1] by continuous i.v infusion during the operation. The same volume of isotonic solution was administered to the other twenty patients as a control group. Intraoperative bleeding, operative field visibility, duration of surgery as well as postoperative recovery were evaluated using a quality scale. In the [Mg] sulphate group, there was a reduction in surgical time 60.2 +/- 15 min vs. 88.1 +/- 10 min, however, the recovery time was 12 min longer and thus presuming a prolongation in anaesthetic emergence. There was a significant reduction of blood loss in [Mg] sulphate group 160 +/- 19 ml vs. 270 +/- 25 ml. The preanesthetic and preoperative Mean Arterial Pressure [MAP] were not significantly different between both groups [p= 0.102 and [p=0.716] respectively, but at 5,10,15,30 and 60 min and at end of surgery, they were significantly lower in the [Mg] sulphate group [p<0.001]. A similar pattern was seen with heart rate. In the [Mg] sulphate group, the anesthetic requirements [fentanyl, vecuronium and sevoflurane], were also significantly reduced [p<0.001]. We conclude that induced arterial hypotension caused by continuous infusion of magnesium sulphate during general anesthesia in functional endoscopic sinus surgery [FESS] led to a useful reduction of intraoperative bleeding and improvement of operative field visibility, as well as reduction of duration of surgery and anesthetic requirements but with delay in emergence time

Premedication with low-dose oral midazolam reduces the incidence of emergence agitation in paediatric patients after sevoflurane anaesthesia

Sevoflurane is a volatile anaesthetic agent with low pungency, nonirritating odor, and low blood/gas partition coefficient that makes it an attractive alternative to halothane. However, a high incidence of emergence agitation [EA] has been reported in paediatric patients after sevoflurane anaesthesia. The underlying mechanism of sevoflurane-induced EA remains unclear. Rapid recovery of consciousness [emergence] from sevoflurane anaesthesia has been proposed as one possible mechanism. It was, therefore, hypothesized that sedatives such as midazolam may counteract sevoflurane's rapid emergence and thus reduce the incidence and the severity of sevoflurane-induced EA. This prospective, controlled, single-blinded study included 88 ASA class I or II paediatric patients scheduled for elective outpatient surgery. Patients were assigned to receive either oral midazolam [0.2 mg kg-_ as anaesthetic premedication] or saline [oral normal saline as premedication] before the conduct of anaesthesia. Induction and maintenance of anaesthesia were uniform in both groups. Induction of anaesthesia was made possible with 8% sevoflurane and N2O in 50% O2. Intubation was performed straight without the aid of muscle relaxant and the ventilator was set to maintain normocapnia. Anaesthesia was maintained with 3% sevoflurane and N2O in 50% O2 until the surgery was over. All matters of relevant time periods were recorded [induction, surgical procedure, extu bation and transportation]. In the post-anaesthesia care unit [PACU], adverse events, the incidence and the severity of EA, analgesic requirement, duration of PACU stay, and parental as well as PACU nurses' satisfaction were evaluated. A significant lower incidence and less severity of EA were noted in patients premedicated with midazolam. Less postoperative analgesia was required in patients who had received midazolam. Although midazolam premedicated patients remained sedated after sevoflurane anaesthesia, the duration of the PACU stay was not significantly different from that of saline-treated patients. Both parents and PACU nurses were more satisfied with midazolam as premedication. It was concluded that premedication with oral midazolam is safe, convenient and effective in decreasing the occurrence of sevoflurane-induced Emergence agitation [EA]. It does not delay discharge from PACU and is suitable for outpatient surgery

Hemodynamic and catecholamine stress responses to insertion of the combitube as an alternative airway management in general anaesthesia for caesarean section

The introduction of Combitube to the field of airway management brought about a solution of the problem of difficult airway in trauma patients and during cardiopulmonary resuscitation. This trial was designed to assess the efficacy of Combitube in preventing the lethal complications of failed Intubation during caesarean section and compare the haemodynamic and stress response to the device with that resulting from endotracheal intubation. Forty-five healthy parturients scheduled for CS were randomized Into three equal groups. Combitube was inserted blindly in group I and facilitated by laryngoscopy in group II In group III, endotracheal intubation was performed under laryngoscopy. Patients were assessed for the degree of difficulty of insertion of the Combitube, manifestation of regurgitation or trauma to the oropharynx. haemodynamic changes and hormonal response to Combitube Insertion and endotracheal intubation. There was no significant difference in the degree of ease on Introduction of Cornbitube in group I as compared to group II. Combitube proved to be a safeguard against regurgitation as group I and II were compared to group III A high incidence of trauma was noticed in group I during blind insertion of Combitube as compared to laryngoscopy aided insertion in group II or endotracheal Intubation in group III Laryngoscopy aided Insertion of Combitube [group II] or endotracheal intubation [group III] produced a significant increase In heart rate as compared to blind insertion in group I. Comparison between groups II and III showed a significant increase In HR in group III. Systolic blood pressure Increased significantly in group III while the other two groups manifested an insignificant increase. Stress hormones manifested increases in all the groups. Nor- adrenaline level increased insignificantly in group I and II. while it was statistically significant In group III. Adrenaline levels increased insignificantly in all the study groups. Prolactine level increased insignificantly In group I and manifested a significant increase in groups II and III. This Increase was significantly higher in group III as compared to group II. It is concluded that Combitube provides a safe patent airway not only in emergency situations but also in patients scheduled for surgery if they were at risk of aspiration or difficult intubation as those scheduled for caesarean section

dose response study of three different concentrations of clonidine with local anesthetic mixture for peribulbar block

Clonidine, the alpha[2] agonist prolong anesthesia and analgesia when added to local anesthetics, in epidural anesthesia, subarachnoid anesthesia, plexus anesthesia and retrobulbar block. We evaluate the dose-response relationship of different concentrations of clonidine added to lidocaine in peribulbar block. Sixty patients undergoing cataract surgery were given peribulbar block with 7-10 ml of 2% lidocaine and hyaluronidase with either saline [control] or clonidine 0.5 ug/kg [0.5 clon] 1.0 ug/ kg [1.0 clon] or 1.5 ug/kg [1.5 clon] doses. The onset of globe anesthesia, akinesia and analgesia, the duration of anesthesia and analgesia, the postoperative analgesia requirement and the adverse effects [Hypotension, bradycardia, hypoxia, sedation and dizziness] were recorded. The onset of block was comparable in all groups. The duration of globe anesthesia, analgesia and akinesia was significantly [p<0.01] prolonged in patients receiving 1.0 and 1.5 ug/kg clonidine as compared with the control group. Perioperative pain scores and analgesic requirements were significantly less in these groups. 0.5 ug/kg clonidine did not significantly increase the duration of anesthesia and analgesia. The side effects were observed more with 1.5 ug/kg clonidine as compared with other groups. We conclude that 1.0 ug/kg clonidine significantly prolong the anesthesia and analgesia when mixed with local anesthetic with minimal side effects

Small doses of rocuronium versus mivacurium for short procedures

Rocuronium bromide is a non-depolarizing muscle relaxant [NDMR]. It has a fast rate of onset of action, intermediate duration and rapid recovery. Mivacurium is a short acting [NDMR] that undergo rapid breakdown by plasma cholinesterase leads to rapid spontaneous recovery. In this study rocuronium, in two small doses 0.3 and 0.45mg/ kg were compared with mivacurium 0.2mg/kg as regard, intubations, onset, clinical duration and reversal either spontaneous or induced, using neostagmine and glycopyrrolate. This study divided into two parts. In part I, quality of neuromuscular block for intubation was studied, 90 patients were allocated randomly to one of three groups [n=30] to receive rocuronium 0.3mg/kg [group 1], rocuronium 0.45mg/kg [group 2] and mivacurium 0.2mg/kg [group 3]. Each group divided into two equal subgroups [a and b]. The trachea was intubated after 60 sec in subgroups la and 2a, after 90 sec in subgroup Ib, 2b and 3a and after 120sec in subgroup 3b. Intubating conditions were graded as excellent, good or poor. In part II, assessment of onset, clinical duration and time for reversal were studied. 90 patients were randomly assigned to one of three groups [n=30], group I received rocuronium 0.3mg/kg, group II received rocuronium 0.45mg/kg and group III received mivacurium 0.2mg/kg. The onset, maximum degree of block and clinical duration were measured. When T[25] was reached, the three groups divided into equal subgroups a and b. Subgroups la, Ila and IlIa undergo spontaneous recovery and subgroups Ib lIb and Illb were received neostagmine 50 micro g/kg and glycopyrrolate 10microg/kg. Results: The frequency of distribution of excellent and good in-tubating conditions were high in subgroups 2b and 3b, but the patients with excellent conditions were more in subgroup 3b, no patient with poor intubating conditions in both subgroups. There were no significant difference between the subgroups Ib, 2a and 3a regarding intubation conditions. The onset was significantly rapid in group II and slow in group III, clinical duration was significantly longer in group II compared with groups I and II. While there were no significant difference, in clinical duration of action, between groups I and II. When spontaneous recovery time TOP [0.7] compared, we found that group III had significantly short spontaneous recovery time. On the other side, group II had significantly long spontaneous recovery time. In groups I and II, the induced recovery time were much rapid than spontaneous. While in group III there was no significant difference between spontaneous or induced recovery. Rocuronium has minimal side effects, provides conditions more suitable for rapid tracheal intubation. With small doses 0.3 and 0.45mg/kg of rocuronium, clinical duration of action became short and recovery, especially induced, became rapid. Rocuronium can be used for short procedures, but a dose of 0.45mg/kg was more accepted as intubating dose especially when intubations were attempted after 90sec. A dose of 0.3mg/kg can be used as intubating dose only under adequate anesthetic depth. Mivacurium as short acting muscle relaxant may be beneficial for short procedures. Also, spontaneous recovery of mivacurium was significantly short while there was no significant difference in induced recovery when compared to rocuronium either 0.3 or 0.45mg/kg, but its delayed onset made it unsuitable for rapid intubations. The principal side effects of mivacurium are facial flushing and transient fall in blood pressure due to moderate histamine release. The duration of action of mivacurium is prolonged in patients with atypical plasma cholinesterase as well as those with end stage liver or renal disease. Mivacurium is indicated for short procedures when anticholinesterase agents must be avoided

Intrapartum fever: is it a complication for epidural analgesia used for labor pain?

This study was designed to evaluate the impqct of epidural analgesia [EDA] during labor on the rate of intrapartum fever [IFF] and neonatal outcome, and to compare the safety and efficacy of two local anesthetic agents for EDA. Seventy-five primigravida were allocated in three equal groups: control group received ho analgesia, EDA[R] received EDA using ropivacaine 0.25% and EDAg received bupivacaine 0.25%. Epidural infusion was discontinued at full cervical dilatation. Patients were monitored for sensory and motor blockade data, progress of labor, the frequency and time of occurrence of spontaneous rupture of membrane [SROM] and the mode of delivery. Maternal temperature was monitored and time of occurrence, rate and degree of IFF [>/= 38°C] and the need for treatment was assessed and neonatal outcome was evaluated. IFF occurred in 30 parturients [5 control and 25 in EDA groups], with non-significant difference in mean temperature between both EDA groups and control group and versus each other. IFF occurred mainly in parturients exposed to prolonged duration of EDA, with increased incidence of SROM and meconium in liquor in febrile women. Moreover, all parturients required cesarean section [CS] were febrile, also there is increased need for instrumental delivery in febrile women. All feverish parturients received fluid and antipyretic therapy and 8 required antibiotic treatment Within the first 24h postpartum, 3 patients in EDA group were still feverish, but responded to treatment during the next day. Apgar score <9, at 5 min, u;os reported in only 8 newborns 1 [4%] in control 3 [12%] and 4 [16%] in both EDA groups. Two of control newborns and 5 in EDA groups had respiratory distress. Neonatal infection, mild chest infection, was detected in 2, but in 7 newborns in control and EDA groups, respectively. Seven newborns [1 in control and 6 in EDA groups] required admission to newborn intensive care unit [NICU]. Newborns for febrile women showed worse outcome than those delivered to afebrile women. We can conclude that there is an unexplained association between epidural analgesia during labor and in-trapartum fever [IFF] irrespective of the type of the drug used; however, being an effective modality for alleviation of labor pain, EDA cannot be abandoned