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O May

Publications and source records attributed to O May.

At least 19 recordsLinked to original sources

[Transabdominal removal of femoral and acetabular components of a severely protruded and infected hip arthroplasty with urinary tract complications].

We present the first report of transabdominal removal of femoral and acetabular components of a severely loosened hip prosthesis protruding into the pelvis. In a 73-year-old woman post-operative development of urinary tract complications emphasize importance of careful assessment of the prosthetic relations with the vascular and nervous structures as well as pelvic organs before removal of the hip prosthesis. Angio-computed tomography is the most contributive exploration to assess vascular relations. In patients with particular clinical presentations or with threatened structures in the vicinity of the prosthesis, this examination must be completed by complementary opacifications (urinary and gastrointestinal tracts, joints). Ureteral catheterization may be needed if the structures are close or if there is a suspected modification of the urinary tract (retraction, mass effect). In present case, we did not opacify the urinary tract before laparatomy despite the presence of urinary signs preoperatively. A suspected ureterovaginal fistula was discovered. But they where also a ureteral lesions which can result from difficult dissection in contact with infected tissues. In this patient, urinary complications led to nephrectomy after temporary pyelostomy for urine bypass. At last follow-up, the urinary tract infection was controlled but reimplantation was not attempted because of insulin dependent diabetes mellitus and poor general condition. The spontaneous course of this infection with prosthesis loosening recalls the importance of regular surveillance of total hip replacements.

Abdomen↗

Bias of QT dispersion.

BACKGROUND: Prolonged QT dispersion (QTD) is associated with an increased risk of arrhythmic death but its accuracy varies substantially between otherwise similar studies. This study describes a new type of bias that can explain some of these differences. MATERIAL: One dataset (DiaSet) consisted of 356 subjects: 169 with diabetes, 187 nondiabetic control persons. Another dataset (ArrSet) consisted of 110 subjects with remote myocardial infarction: 55 with no history of arrhythmia and 55 with a recent history of ventricular tachycardia or fibrillation. METHODS: 12-lead surface ECGs were recorded with an amplification of 10 mm/mV at a paper speed of 50 mm/s. The QT interval was measured manually by the tangent-method. The bias depends on the magnitude of the measurement errors and the measurable part of the bias increases with the number of the repeated measurements of QT. RESULTS: The measurable bias was significant for both datasets and decreased for increasing QTD in the DiaSet (P < 0.001) and in the ArrSet (P = 0.11). The bias was 2.5 ms and 1.9 ms at QTD = 38 ms and 68 ms, respectively, in the ArrSet, and 7.5 ms and 2.8 ms at QTD = 19 ms and 55 ms, respectively, in the DiaSet. CONCLUSIONS: This study shows that random measurement errors of QT introduces a type of bias in QTD that decreases as the dispersion increases, thus reducing the separation between patients with low versus high dispersion. The bias can also explain some of the differences in the mean QTD between studies of healthy populations. Averaging QT over three successive beats reduces the bias efficiently.

Aged↗

Reinventing the wheel.

Explore the source record for details and available documents.

Directed Molecular Evolution↗

Inverting enantioselectivity by directed evolution of hydantoinase for improved production of L-methionine.

Using directed evolution, we have improved the hydantoinase process for production of L-methionine (L-met) in Escherichia coli. This was accomplished by inverting the enantioselectivity and increasing the total activity of a key enzyme in a whole-cell catalyst. The selectivity of all known hydantoinases for D-5-(2-methylthioethyl)hydantoin (D-MTEH) over the L-enantiomer leads to the accumulation of intermediates and reduced productivity for the L-amino acid. We used random mutagenesis, saturation mutagenesis, and screening to convert the D-selective hydantoinase from Arthrobacter sp. DSM 9771 into an L-selective enzyme and increased its total activity fivefold. Whole E. coli cells expressing the evolved L-hydantoinase, an L-N-carbamoylase, and a hydantoin racemase produced 91 mM L-met from 100 mM D,L-MTEH in less than 2 h. The improved hydantoinase increased productivity fivefold for >90% conversion of the substrate. The accumulation of the unwanted intermediate D-carbamoyl-methionine was reduced fourfold compared to cells with the wild-type pathway. Highly D-selective hydantoinase mutants were also discovered. Enantioselective enzymes rapidly optimized by directed evolution and introduced into multienzyme pathways may lead to improved whole-cell catalysts for efficient production of chiral compounds.

Amidohydrolases↗

Cardiovascular autonomic neuropathy in insulin-dependent diabetes mellitus: prevalence and estimated risk of coronary heart disease in the general population.

OBJECTIVES: The aim of the study was to estimate the prevalence of cardiovascular autonomic neuropathy (CAN) in Type 1 diabetes mellitus in the general population and to assess the relationship between CAN and risk of future coronary heart disease (CHD). METHODS: The Type 1 diabetes mellitus population in the municipality of Horsens, Denmark, was delineated by the prescription method and a random sample of 120 diabetics aged 40-75 years was recruited. Type 1 diabetes mellitus was registered if fasting C-peptide was below 0.30 nmol L(-1). The E/I ratio was calculated as the mean of the longest R-R interval in expiration divided by the shortest in inspiration during deep breathing at 6 breaths min(-1) and taken to express the degree of CAN. A maximal symptom-limited exercise test was carried out and the VA Prognostic Score, indicating risk of cardiovascular death or non-fatal myocardial infarction, was computed. Additionally, the 10-year risk of CHD was calculated using the Framingham model. RESULTS: A total of 84 people responded, of whom 71 had Type 1 diabetes mellitus. The E/I ratio was measured in 69 people. The prevalence of CAN expressed as an E/I ratio below the normal 5th percentile was 38%. The E/I ratio was significantly reduced in old age, long duration of diabetes, female gender, high fasting blood glucose, triglyceride, systolic blood pressure and urinary albumin excretion. A high risk of future CHD calculated using the Framingham model was associated with a low E/I ratio (r = -0.39, P = 0.001). Exercise capacity, rise in systolic blood pressure and heart rate were positively correlated with the E/I ratio. A high VA Prognostic Score was correlated with a low E/I ratio (r = - 0.58, P < 0.0005). The risks estimated by the two models were significantly correlated (r = 0.60, P < 0.0005). CONCLUSION: The prevalence of CAN in the 40-75-year-old Type 1 diabetes mellitus population is estimated to be 38%. CAN is associated with exercise test parameters and a coronary risk factor profile indicating a high risk of future CHD.

Adult↗

[Testing a computer-assisted bending machine for manufacturing orthodontic treatment elements].

The use of suitable orthodontic devices producing desired defined force systems is of importance for successful orthodontic treatment. Bending loops can be difficult and time-consuming. Computerised fabrication would enable very precise reproduction of individual loops. A bending machine has now been developed within the framework of a computer-assisted treatment concept. In this study, a prototype machine was used to fabricate U-, T- and delta loops made of stainless steel, cobalt chromium and titanium molybdenum wire. The various geometric parameters of each loop were measured to determine how precisely they had been produced. Furthermore, the force system of each loop were experimentally investigated during simulated activation in an orthodontic measurement and simulation system. The results indicate that the geometric parameters had an average error of 2.8 degrees for angles and 0.9 mm for lengths. Owing to the fabrication errors, loops of the same type produced different force systems. Overall, the new bending machine can fabricate different types of loop, but the requirements of very precise fabrication are currently not met. This fact, together with further limitations in terms of configuration, means that the machine cannot be used routinely at present. However, the machine can nevertheless be considered a good basis for further development.

Computer-Aided Design↗

Increased QT dispersion in patients with insulin-dependent diabetes mellitus.

AIM: To compare the QT dispersion in unselected patients with insulin-dependent diabetes mellitus to non-diabetic control subjects and to assess the association between the QT dispersion and cardiac autonomic neuropathy, ischaemic heart disease, blood pressure level and nephropathy. METHODS: 42 patients with insulin-dependent diabetes mellitus and 80 control subjects aged 40-57 years participated. The QT interval was measured in a resting 12-lead electrocardiogram (ECG) and the QT dispersion defined as the difference between the maximum and minimum QT interval. Bazett's formula was used to correct for heart rate (QTc). The degree of cardiac autonomic neuropathy was assessed by five function tests and ischaemic heart disease was defined by a previous myocardial infarction, ECG abnormalities or a positive exercise test. RESULTS: Compared to control subjects, diabetic patients had a longer QTc interval (433 vs. 416 ms; P=0.002) and a higher QT dispersion (36 vs. 30 ms; P=0.02). In the diabetic group, the QTc interval was prolonged in patients with autonomic neuropathy (449 vs. 420 ms; P=0.007) and the QT dispersion was increased in patients with ischaemic heart disease (51 vs. 33 ms; P=0.004). No association was found to urinary albumin excretion rate or blood pressure. CONCLUSION: The QT dispersion as well as the QTc interval is increased in patients with insulin-dependent diabetes mellitus. The association between QT dispersion and ischaemic heart disease indicates that abnormalities in cardiac repolarisation may be caused by complications to diabetes rather than diabetes in itself.

Adult↗

Microbial hydantoinases--industrial enzymes from the origin of life?

Hydantoinases are valuable enzymes for the production of optically pure D- and L-amino acids. They catalyse the reversible hydrolytic ring cleavage of hydantoin or 5'-monosubstituted hydantoins and are therefore classified in the EC nomenclature as cyclic amidases (EC 3.5.2.). In the EC nomenclature, four different hydantoin-cleaving enzymes are described: dihydropyrimidinase (3.5.2.2), allantoinase (EC 3.5.2.5), carboxymethylhydantoinase (EC 3.5.2.4), and N-methylhydantoinase (EC 3.5.2.14). Beside these, other hydantoinases with known metabolic functions, such as imidase and carboxyethylhydantoinase and enzymes with unknown metabolic function, are described in the literature and have not yet been classified. An important question is whether the distinct hydantoinases, which are frequently classified as L-, D-, and non-selective hydantoinases depending on their substrate specificity and stereoselectivity, are related to each other. In order to investigate the evolutionary relationship, amino acid sequence data can be used for a phylogenetic analysis. Although most of these enzymes only share limited sequence homology (identity < 15%) and therefore are only distantly related, it can be shown (i) that most of them are members of a broad set of amidases with similarities to ureases and build a protein superfamily, whereas ATP-dependent hydantoinases are not related, (ii) that the urease-related amidases have evolved divergently from a common ancestor and (iii) that they share a metal-binding motif consisting of conserved histidine residues. The difference in enantioselectivity used for the classification of hydantoinases on the basis of their biotechnological value does not reflect their evolutionary relationship, which is to a more diverse group of enzymes than was assumed earlier. This protein superfamily probably has its origin in the prebiotic conditions of the primitive earth.

Amidohydrolases↗

Parasympathetic function during deep breathing in the general population: relation to coronary risk factors and normal range.

OBJECTIVES: To examine the association between the parasympathetic function assessed by deep breathing-induced heart rate variability (HRV) and coronary risk factors and to establish a reference range for deep breathing-induced HRV. DESIGN: Cross-sectional population-based study. SETTING: The municipality of Horsens, Denmark. SUBJECTS: One hundred and ninety-four individuals aged 40-67 years without diabetes, atrial fibrillation or a pacemaker randomly selected from the population. MAIN OUTCOME MEASURES: During deep breathing at 6 respiratory cycles min-1, an ECG was taken and in three consecutive cycles the longest R-R interval during expiration (E) and the shortest during inspiration (I) were selected. The mean ratio (E/Iratio) and the mean difference in instantaneous heart rate (E/Idiff) were taken as expressions of the parasympathetic function. RESULTS: In multivariate analysis, E/Idiff was reduced with increasing age (P < 0.0005) and left ventricular mass (P = 0.008), with ECG sign of probable previous myocardial infarction (P = 0.020) and the use of cardiac medication (P = 0.018) and positively correlated to heart rate (P = 0.030). The E/Iratio was diminished with increasing age (P = 0.001), left ventricular mass (P = 0.003), waist-hip ratio (P = 0.044), with ECG sign of probable previous myocardial infarction (P = 0.012) and use of cardiac medication (P = 0.020), but no association was found with heart rate (P = 0.92). In both E/Idiff and E/Iratio, no correlation was found to lipids, blood pressure or alcohol consumption. In the group not on cardiac medication, without left ventricular hypertrophy or ECG sign of probable myocardial infarction, E/Idiff and E/Iratio were still independently correlated to age and left ventricular mass. In this group, equations defining the age-corrected 5th percentile were calculated. CONCLUSIONS: The parasympathetic function as assessed by deep breathing-induced HRV in the general population is reduced in older people, and in individuals on cardiac medication, with left ventricular hypertrophy or ECG signs of myocardial infarction. Even in healthy persons the parasympathetic function is inversely associated with age and left ventricular mass. Values of E/Idiff above (4.39-0.033 x age)2 and readings of E/Iratio above 1 + exp (-1.12-0.0198 x age) can be regarded as normal.

Adult↗

Substrate-dependent enantioselectivity of a novel hydantoinase from Arthrobacter aurescens DSM 3745: purification and characterization as new member of cyclic amidases.

A hydantoinase from Arthrobacter aurescens DSM 3745 has been purified to homogeneity with a yield of 77% using a three-step purification procedure. The active enzyme is a tetramer consisting of four identical subunits, each with a molecular mass of 49670 Da as determined by mass spectrometry. The N-terminal amino acid sequence of the enzyme indicates sequence identities to cyclic amidases involved in the nucleotide metabolism as the D-hydantoinase from Agrobacterium radiobacter (53%), the D-selective dihydropyrimidinase from Bacillus stearothermophilus (38%), the allantoinase from Rana catesbeiana (26%), as well as to the catalytic subunit of the urease from Helicobacter pylori (50%). However, all studies based on substrate-dependent growth, induction and catalytic behavior documented the novelty of the bacterial hydantoinase and that its physiological role is not related to any of these enzymes or known metabolic pathways. Its substrate specificity differs from hydantoinases listed in Enzyme Nomenclature and is rather more predominant for the cleavage of aryl- than for alkyl-hydantoin derivatives. It is shown that the stereoselectivity of this enzyme depends on the substrate used for bioconversion: although it is strictly L-selective for the cleavage of D,L-5-indolylmethylhydantoin, it appears to be D-selective for the hydrolysis of D,L-methylthioethylhydantoin. Due to these findings we conclude that this novel bacterial hydantoinase should be classified as a new member of the EC-group 3.5.2 of cyclic amidases.

Amidohydrolases↗

The diurnal variation in blood pressure should be calculated from individually defined day and night times.

The aim of this study was to compare the nocturnal fall in BP parameters calculated from individually defined periods of day and night to values computed from collectively fixed day/night definitions. Day and night periods were defined according to 3 different methods: (i) the individually defined time of getting up and going to bed obtained from participant diaries (MethodIND); (ii) the mean time of rising and retiring in the group (MethodMEAN); and (iii) a daytime period from 07.00-22.00 h as recommended by The Scientific Committee (Method722). The ambulatory BP was recorded every 30 min over 24 h. One hundred and eighty-seven persons aged 40-66 years participated. With MethodIND, the BP load, systolic, diastolic and mean BPs were higher in the daytime and lower in the night-time compared to the results using Method722 and MethodMEAN. The nocturnal BP fall using MethodIND was larger than the fall calculated from every possible fixed division in the period from 3 h before till 3 h after the group mean time of getting up and going to bed (p < 0.001). The lowest frequency of non-dipping, defined as a nightly fall in systolic and diastolic BP below 10%, was observed using MethodIND (10%). Compared to MethodIND, 11% were misclassified as non-dippers by Method722 and 8% by MethodMEAN. We conclude that the diurnal blood pressure variation based on individually defined periods of day and night is larger than the variation based on any collectively fixed day/night definition. It is recommended that assessment of the nocturnal change in BP be based on individually defined periods of day and night.

Adult↗

Molecular evolution of hydantoinases.

The complete amino acid sequence of the hydantoinase from Arthrobacter aurescens DSM 3745 has been derived by automated Edman degradation. This is the first ever reported amino acid sequence of a non-ATP-dependent hydantoinase, which hydrolyzes 5'-monosubstituted hydantoin derivatives L-selectively. A homology search performed in protein and nucleic acid databases retrieved only distantly related proteins. All of these are members of the recently described protein superfamily of amidohydrolases related to ureases (Holm and Sander, Proteins 28: 72-82, 1997). Phylogenetic analysis revealed that the novel hydantoinase forms a new branch separate from other hydantoin cleaving enzymes like dihydropyrimidinases (EC 3.5.2.2) and allantoinases (EC 3.5.2.5). Our results suggests that the enzymes of this protein superfamily have evolved from a common ancestor and therefore are the product of divergent evolution. We show further that the enclosed gene families developed very early in evolution, probably prior to the formation of the three domains, Archaea, Eukarya and Bacteria. Hydantoinases related to ATP-dependent N-methylhydantoinases (EC 3.5.2.14) or 5-oxoprolinases (EC 3.5.2.9) do not belong to this superfamily.

Amidohydrolases↗

Prevalence and prediction of silent ischaemia in diabetes mellitus: a population-based study.

OBJECTIVES: The aim of the study was to estimate the prevalence of silent ischaemia in diabetic subjects in the population, to compare the prevalence of silent ischaemia in diabetics and non-diabetics and to attempt to predict the presence of silent ischaemia in diabetic subjects. METHODS: A random sample of 120 users of insulin and 120 users of oral hypoglycaemic agents aged 40-75 years living in the Danish municipality of Horsens were asked to participate in the study. Corresponding to the youngest half of the sample two non-diabetic controls were randomly selected from the Central Population Register. ST-depression of horizontal or descending character of at least 0.1 mV measured 80 ms after the J-point on either exercise ECG or Holter ECG was considered indicative of myocardial ischaemia. Angina pectoris was considered present if the Rose questionnaire was positive, or chest pain was registered simultaneously with ECG evidence of ischaemia. Individuals with ischaemia, but without angina pectoris, were defined as persons with silent ischaemia. RESULTS: Seventy-four percent of the invited group were included. The observed prevalence of silent ischaemia in diabetics was 13.5% (95% CI = 8.5-19.8%). No association was found between silent ischaemia and gender (P = 0.83) or diabetes type (P = 0.67). In the group of diabetics who had controls, the prevalence was 11.4%, and among the controls the prevalence was 6.4% (OR = 1.87, one-sided P = 0.079). Systolic blood pressure was highly predictive of silent ischaemia in the diabetic subjects (P = 0.005). No predictive value could be shown for other variables. CONCLUSION: This is the first population-based study of silent ischaemia in diabetes. The prevalence of silent ischaemia in diabetic subjects was 13.5%. The frequency of silent ischaemia did not differ significantly between diabetics and non-diabetics. Systolic blood pressure was predictive of silent ischaemia in diabetes.

Adult↗

Crystallization and preliminary X-ray analysis of a hydantoinase from Arthrobacter aurescens DSM 3745.

L-Hydantoinase from Arthrobacter aurescens DSM 3745 has been purified to homogeneity and crystallized from polyethylene glycol solutions in a form suitable for X-ray diffraction analysis. The crystals have been grown by the sitting-drop variant of the vapour-diffusion method. X-ray diffraction studies show that the crystals belong to the monoclinic space group P2(1) with a = 111.2, b = 74.4, c = 146.5 A and beta = 106.7 degrees. Its asymmetric unit contains four monomers related by 222 symmetry. The crystals diffract to at least 2.6 A.

Journal Article↗

[The pisiform bone: sesamoid or carpal bone?].

In man, the pisiform bone occupies an unusual place among the carpal bones. It is situated in an anterior plane to the other bones, sheathed within the tendon of the flexor carpi ulnaris, and ossifying almost four years the last of the carpal bones. Many theories have tried to explain the presence of this "exceptional" bone: the first theory, proposed by Flower and Mivart, suggested the possibility that this bone could be a sesamoid. The second theory supposes a polydactyl hand, assuming that polydactyly preceded pentadactyly; the pisiform would then be a post-minimus vestigial bone according to Bardeleben. Finally, Gegenbauer and Gillies, proposed a primary pentadactyl hand in which the carpus would be composed of three proximal elements, generally two central, and five distal. The pisiform would either be a derivative of the central series, or a distinct element in the carpus. This last theory appears to be the most likely. The primary carpus would therefore have consisted of 12 bones arranged in 3 distinct rows, a proximal row of 3 bones, a central row of 4 bones, and a distal row of 5 bones. According to this theory, the most ulnar of the central would have been displaced to the medial limit of the carpus, to become the pisiform.

Animals↗

The influence of the double burst stimulation (DBS) pattern on the DBS-train-of-four ratio relationship.

UNLABELLED: The double-burst-stimulation (DBS) is a new stimulation pattern developed to facilitate tactile evaluation of residual neuromuscular blockade. DBS consists of two bursts of high frequency stimulations separated by a short time interval. METHODS: By changing these components, the influence of 14 different DBS patterns on the relationship between the DBS ratio and the train-of-four (TOF) ratio was investigated in 70 surgical and 10 intensive care patients during recovery from non-depolarising neuromuscular block. RESULTS: Good linear correlations were observed between the different DBS- and TOF ratios with r2 values ranging from 0.90 to 0.97 (p < 10(-6). At a TOF ratio of 0.70 the DBS ratios ranged from 0.48 to 0.79 when changing between the 14 different DBS patterns. Change in number of pulses had the greatest influence on the slope of the regression line. CONCLUSION: At any chosen level of reversal defined by a TOF ratio, it should therefore be possible to construct a DBS ratio, where fade just can be detected by tactile evaluation.

Anesthesia Recovery Period↗

Optimum time for neostigmine administration to antagonize vecuronium-induced neuromuscular blockade.

We followed the recovery time course in 46 patients antagonized by neostigmine (0.036 mg kg-1) at different levels of vecuronium-induced neuromuscular blockade ranging from post-tetanic count 1 to train-of-four ratio 0.4 and in 15 patients during spontaneous recovery. Non-linear regression curve fit analyses showed that the optimal time for neostigmine administration was when the first twitch in the train of four (T1) was between 1% and 10%. Visual analyses of the scattergram in which the level of block, when neostigmine was given, was plotted against total recovery time (the time elapsed from administration of the last dose of vecuronium to train-of-four ratio 0.7) gave the same result. The reduction in total recovery time achieved by neostigmine was 32.6 min (SE diff. 6.0 min). To achieve the optimum effect, neostigmine must therefore be given 32.6 min plus the required time for peak effect of neostigmine (5.3-7.1 min), i.e. 37.9-39.7 min, before train-of-four ratio 0.7 is reached. During spontaneous recovery this corresponds to a T1 between 1% and 15%.

Adult↗

[The optimal administration time for neostigmine following atracurium blockade. Kinetics of antagonists].

UNLABELLED: The aims of the study were: (1) to predict reversal time from intensive atracurium blockade; and (2) to determine the optimal time of neostigmine administration during recovery from atracurium blockade, i.e., the time at which the administration of neostigmine results in the shortest total recovery time (time from administration of last supplemental dose of atracurium to train-of-four [TOF] ratio 0.70), and at the same time results in the shortest time from administration of neostigmine to TOF ratio 0.70. METHOD: The spontaneous and neostigmine-facilitated recovery in 52 healthy women anaesthetised with thiopentone, fentanyl, droperidol, and nitrous oxide was followed. Post-tetanic count (PTC) of TOF stimulation of the ulnar nerve and mechanomyography were used for monitoring neuromuscular transmission. The neuromuscular blockade was induced with atracurium 0.6 mg/kg and supplemental doses of 0.15 mg/kg were given when the first twitch response in the TOF (TH1) had recovered to 20%. Neostigmine 0.036 mg/kg body weight was given at different levels of neuromuscular blockade to 37 of the patients. RESULTS: Multiple regression analyses including pre-reversal time (time from administration of the last atracurium dose to neostigmine administration), PTC, weight, and age of the patients suggest that pre-reversal time is the best predictor of reversal time: reversal time = 27.3 min - (0.89 x pre-reversal time [min]; (SEE = 6.0 min). If pre-reversal time is unknown, PTC can be used: reversal time = 24 min - (4.5 x ln PTC) at time of reversal); (SEE = 6.8 min). Total recovery time was 47 min (SEM = 2.0 min, n = 15) in the patients allowed to recover spontaneously, and 29 min (SEM = 1.2 min, n = 29) in the patients reversed by neostigmine; the difference of 18 min (SE diff 2.0 min) was significant (P < 0.0005). The level of blockade indicated by PTC (1-24) at the time of reversal had no influence on the total recovery time. The spontaneous recovery times from reappearance of TH1 and TH1 = 10% to TOF ratio 0.70 were 29.2 min (SEM = 1.7 min) and 24.4 min (SEM = 2.6 min), respectively. DISCUSSION: The results suggest that pre-reversal time is the strongest predictor of reversal time when neostigmine is administered during intense atracurium blockade. To achieve the optimal time-saving effect, neostigmine must be given 18 min (the time saved by giving neostigmine) plus 7 to 11 min (needed for neostigmine to reach its peak effect), giving a total of 25 to 29 min before TOF ratio 0.70. As TH1 is between 1% and 10% 25 to 29 min before TOF ratio 0.70 is reached during spontaneous recovery, the optimal level of neuromuscular blockade for neostigmine administration in atracurium blockade is when TH1 is between 1% and 10%. CONCLUSION: Reversal time can be predicted as 27.3 min - (0.89 x prereversal time (min), and the optimal time of neostigmine administration in atracurium blockade appears to be when TH1 is 1%-10%.

Adult↗