Isoflurane inhibits muscle fasciculations caused by succinylcholine in children

The incidence and intensity of muscle fasciculations as well as the occurrence of cardiac arrhythmias following succinylcholine were evaluated in 36 premedicated children (1.0–5.7 years) after intravenous induction with thiopentone or after inhalation induction with isoflurane (3.75 vol-% in 70% nitrous oxide in oxygen). The study was randomized. In the thiopentone group, fasciculations were seen in all children and in the isotlurane group in 5 of 18 children (P<0.001). The median of the duration of fasciculations was 15 s with a minimum of 5 s and maximum of 36 s (1st quartile 9 s and 3rd quartile 20 s) in the thiopentone group and 0 (0–15) s with a 1st quartile of 0 and a 3rd quartile of 3 s in the isoflurane group (P<0.001). No cardiac arrhythmias were noted in either group. In conclusion, isoflurane in nitrous oxide inhibits succinylcholine-induced muscle fasciculations in children.     

Comparison of recovery following rapacuronium, with and without neostigmine, and succinylcholine

The neuromuscular blocking effects of a single dose of rapacuronium 1.5 mg x kg(-1) with or without reversal with neostigmine have been examined in the present study and compared with a dose of succinylcholine 1.0 mg x kg(-1). Neuromuscular block was measured mechanomyographically using train-of-four stimulation. Complete block occurred within 1 min with both agents. Twenty-five per cent recovery of the first response of the train-of-four occurred in a median [range] time of 7.6 [5.7-11.3] min in the succinylcholine group and in 14.2 [8.8-23.6] and 15.1 [9.6-23.4] min in the rapacuronium groups with and without neostigmine reversal, respectively. Spontaneous recovery to a train-of-four ratio of 0.8 took 33.4 [20.0-79.0] min with rapacuronium but this was reduced to about 21.2 [13.9-33.7] min when neostigmine was administered at 25% recovery of first twitch of the train-of-four.     

Vecuronium and Atracurium in the Elderly: A Clinical Comparison with Pancuronium

The intubating conditions, time to complete block and duration of clinical relaxation were observed in a group of 101 elderly patients (aged over 65 years) following pancuronium 0.1 mg kg^-1, vecuronium 0.1 mg kg^-1 or atracurium 0.5 mg kg^-1. The intubating conditions in the three groups were similar when assessed at 2 min following relaxant administration. The time to complete block was shortest with vecuronium (4.3 min) in comparison to atracurium (5.0 min) and pancuronium (6.0 min), but the differences were not statistically significant. The duration of clinical relaxation, however, was significantly shorter with vecuronium (37 min) and atracurium (35 min) in comparison to pancuronium (99 min).     

Microcirculatory hemodynamics after acute blood loss followed by fresh and banked blood transfusion

BACKGROUND: Red blood cell (RBC) conformational changes occur when blood is stored. This study was designed to be a preliminary evaluation to assess how these changes affect the microcirculation. METHODS: The rat cremaster muscle flap model was used to evaluate in vivo microcirculatory changes after withdrawal of 1 mL blood with subsequent administration of fresh blood (group I, n=6) and banked blood (group II, n=6). Each group underwent a 3-stage evaluation: baseline, after blood withdrawal, and after transfusion. Using intravital microscopy, RBC velocity, vessel diameter, functional capillary perfusion, and leukocyte-endothelial interactions were noted. RESULTS: After blood withdrawal, changes in RBC velocity, vessel diameter, functional capillary perfusion, and number of activated leukocytes were observed in both groups, but these changes were more significant in stored blood compared with fresh blood (P相似文献   

Intubating conditions after vecuronium and atracurium given in divided doses (the priming technique)

Intubating conditions have been assessed at 60 s following administration of vecuronium 0.1 mg kg-1 or atracurium 0.5 mg kg-1 given either as a single dose after induction of anaesthesia with thiopentone or in divided doses; vecuronium 0.015 mg kg-1 followed 4 or 6 min later by 0.085 mg kg-1, or atracurium 0.075 mg kg-1 followed 4 or 6 min later by 0.425 mg kg-1. In the divided dose groups the smaller initial (priming) dose was given prior to induction of anaesthesia. Onset and duration of clinical relaxation were assessed using a peripheral nerve stimulator. The intubating conditions at 60 s improved significantly, with the use of relaxants in divided doses being acceptable in 80 and 70% of patients, respectively, with vecuronium and atracurium, but the conditions are not as good as those commonly found using suxamethonium. Priming at 6 min has no advantage over priming at 4 min. The onset of complete block was accelerated with priming, but the difference was not significant. The duration of clinical relaxation of vecuronium was significantly prolonged by giving it in divided doses. Unpleasant awareness of muscle weakness was observed in 15 patients, requiring early induction of anaesthesia in five of them.     

End-tidal CO2 on admission is associated with hemorrhagic shock and predicts the need for massive transfusion as defined by the critical administration threshold: A pilot study

BackgroundCritical administration threshold (≥3 units of packed red blood cells/h or CAT+) has been proposed as a new definition for massive transfusion (MT) that includes volume and rate of blood transfusion. CAT+ has been shown to eliminate survivor bias and be a better predictor of mortality than the traditional MT (>10 units/24 h). End-tidal CO₂ (ET CO₂) negatively correlates with lactate and is an early predictor of shock in trauma patients. We conducted a pilot study to test the hypothesis that low ET CO₂ on admission predicts CAT+.MethodsET CO₂ via capnography and serum lactate were prospectively collected on admission for 131 patients requiring trauma team activation. Demographic data were obtained from patient charts. Excluded were patients with isolated head injuries, traumatic arrests, or pre-hospital intubations. CAT± status was determined for each hour up to 6 h from admission as described; likewise, MT± status was determined up to 24 h from admission.ResultsAfter exclusion criteria, 67 patients were analyzed. Mean age was 41.2 (SD 18.5). Thirty-three patients had a blunt mechanism of injury (49%), median ISS was 9 (interquartile range 4–19), and there were 6 deaths (9%). ET CO₂ and lactate were negatively correlated by Spearman rank-based correlation (rho = −0.41, p = 0.0006). Twenty-one (31%) and 8 (12%) patients were CAT+ and traditional MT+, respectively. There were a significantly greater proportion of patients with ISS > 15, ET CO₂ <35, or who died found to be CAT+. A binomial logistic regression model adjusting for age, SBP <90, HR, and ISS >15 revealed ET CO₂ < 35 to be independently predictive of CAT+ (OR 9.24, 95% CI 1.51-56.57, p = 0.016).ConclusionsThis pilot study demonstrated that low ET CO₂ had strong association with standard indicators for shock and was predictive of patients meeting CAT+ criteria in the first 6 h after admission. Further study to verify these results and to elucidate CAT criteria’s association with mortality will require a larger sample size.     

The effect of succinylcholine on energy metabolism studied by 31 P-NMR spectroscopy in rat denervated skeletal muscle

Background : The goals of this study were: (1) to demonstrate the differences of metabolic changes induced by succinylcholine (SCh) administration between normal and denervated muscle by ³¹P-NMR spectroscopy: (2) to determine whether three kinds of drugs (vecuronium, midazolam and magnesium sulfate) could prevent these metabolic changes.
Methods : Following unilateral sciatic nerve section, 20 male Wistar rats were studied at three-week intervals. After SCh 1 mg·kg^-1 was administered intravenously, the changes of the inorganic phosphate/phosphocreatine (Pi/PCr) ratio, the β ATP/(PCr+Pi) ratio, and intracellular pH were measured by ³¹P-NMR both in normal and denervated hind limb muscles of 5 rats. The other 15 rats were allocated to the pretreatment groups by the following drugs: vecuronium 0.02 mg·kg^-1, midazolam 0.1 mg·kg^-1 and magnesium sulfate 60 mg·kg^-1. After pretreatment 3 min before SCh administration, we measured the same parameters by ³¹P-NMR.
Results: SCh administration did not change the Pi/PCr ratio in normal muscle, but significantly increased that in denervated muscle (P<0.05). This increase of the Pi/PCr ratio was also observed in all pretreated groups but was minimal as compared with that in non-pretreatment denervated muscle.
Conclusion : These data suggested that SCh administration decreased the level of "energy reserve" in denervated muscle, and that this metabolic change was not totally inhibited by vecuronium, midazolam, or magnesium sulfate.     

Plasma cholinesterase and abnormal reaction to succinylcholine: twenty years' experience with the Danish Cholinesterase Research Unit

For more than 20 years, the Danish Cholinesterase Research Unit (DCRU) has collected information about patients showing an abnormal response to succinylcholine.
The purpose of this study was, on the basis of the 20 years' experiences with the Unit, to evaluate our clinical findings in patients referred because of prolonged response following succinylcholine. Also, we wanted to evaluate the results of our prospective controlled studies of the effect of succinylcholine in patients with normal and abnormal plasma cholinesterase genotypes.
An explanation for the apparent abnormal response to succinylcholine was found in 61.1% of the 1,247 patients referred to the Unit. Of the 1,247 patients, 28.5% were genotypically normal and 46.5% had an abnormal genotype. In the remaining 24.9% of the patients, the genotype could not be established. The time to sufficient recovery of neuromuscular function following succinylcholine 1.0–1.5 mg kg^-1 was 15–30 min in patients heterozygous for one abnormal gene, 35–45 min in patients heterozygous for two abnormal genes and 90–180 min in patients homozygous for the atypical gene. Patients with two newly discovered genotypes (AK (5 patients) and AH (1 patient)) showed slightly prolonged (20 min) and markedly prolonged (90 min) duration of action of succinylcholine, respectively.
Our results indicate that it is a problem for many anaesthetists to correctly diagnose a prolonged response to succinylcholine. We therefore urge the anaesthetist always to use a peripheral nerve stimulator when faced with a case of apparent abnormal response to succinylcholine.     

Anaphylactoid reaction associated with blood transfusion during anesthesia

Key words  anaphylactoid reaction - blood transfusion - hemodynamics     

The onset of ablation of the evoked adductor pollicis muscle twitch in children: a clinical perspective

The time to loss of the adductor pollicis muscle response to ulnar nerve stimulation at 1 Hz (twitch) after succinylcholine, 1.5 mg.kg-1 intravenously (IV), or vecuronium, 0.1 mg.kg-1 (IV), administration was assessed visually in 134 children, age 2-13 yr, during clinically determined, deep halothane, enflurane and isoflurane anaesthesia. The overall time to twitch ablation and duration of succinylcholine's action is in agreement with published times obtained under controlled experimental conditions; the onset time following vecuronium is comparable to those observed during a similar anaesthetic background measured under controlled experimental conditions. Twitch ablation after succinylcholine was achieved in half the time needed following vecuronium regardless of anaesthetic agent. Succinylcholine's and vecuronium's onset time as well as succinylcholine's duration is adequately assessed by the outlined, simple clinical means. The choice of inhalation agent does not affect the time to visible twitch ablation in a clinically relevant manner; nor does it make an appreciable difference, in clinical terms, in succinylcholine's duration of action.     

Tracheal intubation conditions after one minute: rocuronium and vecuronium, alone and in combination

Rocuronium is a recently introduced nondepolarising neuromuscular blocking agent with a rapid onset and intermediate duration of action. Experimental observations have suggested that during onset it acts synergistically with other nondepolarising agents, but that at a steady state the combined action is additive. In order to investigate whether synergism during onset produces a clinical benefit we performed the following study of tracheal intubation conditions. Consenting patients presenting for elective surgery which required tracheal intubation were randomly allocated to receive a standard anaesthetic and either a twice ED₉₅ dose of rocuronium, or vecuronium, or an equipotent mixture of both drugs. Tracheal intubation conditions were assessed after 60 s and scored as excellent, good, poor or impossible. The conditions produced in the rocuronium and the mixture groups were similar and both were significantly better than those of vecuronium. Excellent intubation conditions were achieved in 57% of the rocuronium group, 70% of the mixture group and 27% of the vecuronium group. We conclude that a mixture of rocuronium and vecuronium acts synergistically during the early part of their action and a mixture containing one ED₉₅ of both agents provides comparable conditions for tracheal intubation as an equipotent dose of rocuronium.     

Comparison of intubating conditions with atracurium, vecuronium and pancuronium

A blind trial, comparing time of onset of satisfactory conditions for tracheal intubation with atracurium 0.6 mg/kg, vecuronium 0.1 mg/kg and pancuronium 0.1 mg/kg is described. Intubation was attempted at 30-second intervals in 60 patients, randomly allocated to receive one of the above muscle relaxants. Patients receiving atracurium 0.6 mg/kg could be intubated from 30 to 120 seconds. Patients receiving either vecuronium 0.1 mg/kg or pancuronium 0.1 mg/kg were able to be intubated between 60 and 240 seconds. The results showed a statistically significant earlier onset of satisfactory intubating conditions with atracurium than with vecuronium or pancuronium in these doses but no difference between vecuronium and pancuronium.     

Anaemia and blood transfusion: incorporating patient blood management

Both red blood cell (RBC) transfusion and anaemia or low haematocrit increase morbidity and mortality associated with surgery. Chronic anaemia in the elective patient carries a small risk in non-haemorrhagic surgery. Where bleeding is anticipated anaemia should be treated medically to avoid (RBC) transfusion which will increase the risk to the patient. Major bleeding (MB) has the biggest impact on adverse outcomes. Acute anaemia is caused by surgical bleeding and requires RBC transfusion to keep the haematocrit (Hct) above 21% and haemoglobin (Hb) above 7 g/dl in patients without coronary artery disease (CAD) and between Hct 24–27% or Hb >8 g/dl in patients with CAD. Having a patient blood management programme can mitigate the problem. Medical, surgical and anaesthetic planning are paramount to avoid bleeding and transfusion which together have a significant impact on adverse outcomes for the patient.     

急诊手术围手术期输血与术后感染及并发症的关系

目的 分析急诊手术患者围手术期输血与术后感染的关系。方法 收集2011年至2015年部分急诊手术住院患者病历资料,包括患者基线资料、围手术期临床和实验室数据以及住院期间并发症资料。输血的定义范围为从患者入院到出院的任何输血事件。主要记录术后感染性事件,包括切口和手术部位感染、伤口裂开、尿路感染、肺炎、败血症和感染性休克;次要记录包括住院时间、非计划气管插管、呼吸机使用超过48小时、急性肾衰竭,任何血栓栓塞事件和意外再次手术探查等。结果 在收集到的3153例急诊手术患者中,共242例（7.7%）接受输血治疗,接受输血患者年龄大于无输血患者,输血组BMI低于未输血组;输血患者ASA分类3级和4级低于未输血组;输血患者的平均总手术时间、总住院时间比无输血组长;输血患者发生血栓栓塞并发症的风险,如肺栓塞、深静脉血栓、呼吸功能障碍的风险增高;输血患者更有可能进行非计划气管插管。本组病例共594例患者（18.83%, 594/3135）发生术后感染事件,其中输血患者的感染率占所有输血者的39.7%（96/242）;糖尿病、COPD、慢性心脏病和高血压等慢性疾病史有显著性差异;体重减轻超过10%、较高ASA评分及污染严重伤口更容易感染;皮质类固醇使用、出血性疾病的也更容易感染。此外,低蛋白血症、低血细胞比容和也存在显著差异;开放手术感染率高于腹腔镜手术。结论 急诊手术患者接受输血与术后感染性并发症的风险增加有关。     

Massive transfusion in trauma: blood product ratios should be measured at 6 hours

Background: Most potentially preventable haemorrhagic deaths occur within 6 h of injury. Conventionally, blood component therapy delivery is measured by 24‐h cumulative totals and ratios. The study aim was to examine the effect of a massive transfusion protocol (MTP) on early (6 h) balanced component therapy. Methods: An 88‐month retrospective clinical study at a level 1 trauma centre was undertaken, examining consecutive trauma patients receiving ≥10 units of packed red blood cells (PRBCs) within 24 h, before (pre‐MTP) and after implementation of MTP. Demographic data, injury severity score (ISS), abbreviated injury scale (AIS), shock parameters, coagulation profile, the need for surgical intervention (<24 h), mortality and intensive care unit length of stay were collected. The ratios of blood products given by 6 h, by 24 h and the time between administrations of components was collected and analysed. Results: Pre‐MTP and MTP patients had similar demographics, shock severity and initial laboratory findings. Despite MTP patients having had a higher ISS (42 ± 12 versus 36 ± 12, P < 0.05) and AIS head score (2.6 ± 1.8 versus 1.6 ± 2.0, P < 0.05), there was no difference in mortality. Area under the curve (AUC) of the MTP period showed earlier delivery of higher median ratios of fresh frozen plasma (FFP)/PRBC (P= 0.004). Similar findings were found for cryoprecipitate/PRBC and platelet/PRBC ratios. By 24 h, the AUC for FFP/PRBC ratios were no different. Discussion: Implementation of MTP resulted in earlier balanced transfusion. The difference between the FFP/PRBC ratios of the two types of resuscitations levelled by 24 h. The efficacy of component therapy delivery should be measured earlier than 24 h.     

Neuromuscular blocking effects and train-of-four fade with cisatracurium: comparison with other nondepolarising relaxants

Neuromuscular blocking drugs exhibit different degrees of fade in response to train-of-four stimulation believed to represent their relative prejunctional effects. The present study was designed to compare the train-of-four fade after cisatracurium and compare this with other commonly used muscle relaxants. Train-of-four fade during onset and recovery of block were recorded after administration of cisatracurium 0.05 or 0.1 mg.kg-1, atracurium 0.5 mg.kg-1, vecuronium 0.08 mg.kg-1, mivacurium 0.15 mg.kg-1 or rocuronium 0.6 mg.kg-1 to patients anaesthetised with fentanyl, nitrous oxide and a propofol infusion. Neuromuscular monitoring was by stimulation of the ulnar nerve and recording the force of contraction of the adductor pollicis muscle. The onset and recovery of block were also measured. Train-of-four fade during onset of block was greater with the lower dose of cisatracurium compared with the higher dose of cisatracurium and all other relaxants. Train-of-four fade during recovery was similar. The median times (and ranges) for the onset of maximum block were 3.4 (2.1-5.6), 1.5 (1.2-2.3), 2.1 (1.2-2.6), 2.0 (1.5-2.7) and 1.0 (0.7-1.3) min for cisatracurium 0.1 mg.kg-1 and atracurium, mivacurium, vecuronium and rocuronium, respectively. The median times (and ranges) for the recovery of T1 to 25% of control and to a train-of-four ratio of 0.8 were 41 (21-50) and 65 (40-78); 43 (37-54) and 69 (58-79); 15 (11-20) and 25 (19-30); 31 (23-46) and 60 (45-117); and 33 (18-57) and 50 (28-76) min following cisatracurium, 0.1 mg.kg-1, atracurium, mivacurium, vecuronium and recuronium, respectively.     

Evaluation and management of haemorrhagic shock in polytrauma: Clinical practice guidelines

Haemorrhagic shock is the most common preventable cause of early mortality in polytrauma patients. Road traffic injuries are the most common cause for polytrauma and most commonly include orthopaedic injuries. Hence, orthopaedic trainees and junior orthopaedic surgeons need to be well aware of evaluation and management of haemorrhagic shock in the multiple injured patient. The present narrative review discusses evaluation and current principles in management of haemorrhagic shock in a polytrauma patient. A classification system for haemorrhagic shock based on ATLS guidelines has been described along with novel use of colour coding to facilitate better and effective use of the classification. A treatment algorithm has also been presented for quick reference. The emphasis is to avoid overloading with crystalloid fluids, replacing with blood and blood products (Balanced resuscitation), permissive hypotension, prevent and acutely treat lethal conditions such as hypothermia, acidosis and coagulopathy. The management of haemorrhagic shock in polytrauma patient is quite challenging and require a detailed knowledge of its management. An arbitrary and haphazard management of these patients may lead to severe complications. We have mentioned the broad principles of management of hypovolemic shock in a polytrauma patient.