Development of Software for Automatic Analysis of Intervention in the Field of Homeopathy.

OBJECTIVE: To study the effect of homeopathic medicines (in higher potencies) in normal subjects, Peripheral Pulse Analyzer (PPA) has been used to record physiologic variability parameters before and after administration of the medicine/placebo in 210 normal subjects. METHODS: Data have been acquired in seven rounds; placebo was administered in rounds 1 and 2 and medicine in potencies 6, 30, 200, 1 M, and 10 M was administered in rounds 3 to 7, respectively. Five different medicines in the said potencies were given to a group of around 40 subjects each. Although processing of data required human intervention, a software application has been developed to analyze the processed data and detect the response to eliminate the undue delay as well as human bias in subjective analysis. This utility named Automatic Analysis of Intervention in the Field of Homeopathy is run on the processed PPA data and the outcome has been compared with the manual analysis. The application software uses adaptive threshold based on statistics for detecting responses in contrast to fixed threshold used in manual analysis. RESULTS: The automatic analysis has detected 12.96% higher responses than subjective analysis. Higher response rates have been manually verified to be true positive. This indicates robustness of the application software. The automatic analysis software was run on another set of pulse harmonic parameters derived from the same data set to study cardiovascular susceptibility and 385 responses were detected in contrast to 272 of variability parameters. It was observed that 65% of the subjects, eliciting response, were common. CONCLUSION: This not only validates the software utility for giving consistent yield but also reveals the certainty of the response. This development may lead to electronic proving of homeopathic medicines (e-proving).

Detection of seizure activity in the paralyzed neonate using continuous monitoring.

In experimental animals neurologic damage may occur during seizure activity whether the seizure is accompanied by motor activity and hypoxemia or whether the animal is paralyzed and normoxemic. These findings suggest that it may be important to detect seizure activity in the paralyzed neonate. Nine infants who were mechanically ventilated and paralyzed with pancuronium had their condition diagnosed as seizure activity. Vital signs were continuously monitored and six infants had either oxygen saturation or transcutaneous oxygen measured during seizure activity. For the group as a whole, rhythmic fluctuations in vital signs, cardiac rhythm, and oxygenation occurred every four minutes (range one to seven minutes) and lasted two minutes (range one to four minutes). In seven patients whose seizures were not accompanied by cardiac arrhythmias the following mean increases were noted: systolic arterial blood pressure, 15 mm Hg (range 7 to 36 mm Hg); heart rate, ten beats per minute (-11 to 30/min); oxygen saturation, 12% (range 4% to 20%); and transcutaneous oxygen, 31 mm Hg (range 14 to 45 mm Hg). Seizures in the two patients with cardiac arrhythmias were accompanied by a decrease in systolic arterial blood pressure of 27 mm Hg (range 15 to 40 mm Hg) and in oxygen saturation of 24% (range 20% to 28%). The presence of rhythmic fluctuation in vital signs and oxygenation should alert the physician to the possibility of seizure activity in the paralyzed neonate.

Controlled evaluation of muscle relaxation in the ventilated neonate.

To assess the effects of muscle relaxation on the critically ill ventilated neonate, pancuronium bromide was administered for a 12-hour period to ten low-birth-weight neonates (960 to 2,000 gm) of 26 to 34 weeks gestation, all whom required mechanical ventilation and were studied within 48 hours of birth (six to 39 hours). The infants were also studied for a 12-hour period during which no pancuronium bromide was administered. During both study periods, the order of which was randomized, heart rate, blood pressure, PO2, and intracranial pressure were continuously measured. The amounts of handling during the pancuronium and control periods were similar. The results revealed a significantly greater duration of hypoxia (PO2 less than 50 torr) (56.1 vs 23.6 minutes, P less than .001) and hyperoxia (PO2 greater than 70 torr) during the control period (92.5 vs 13 minutes, P less than .001). Durations of intracranial pressure elevation 10 cm H2O above the infant's baseline were significantly less during paralysis (6.7 vs 58.8 minutes, P less than .001) as were spikes of intracranial pressure to greater than 25 cm H2O (1.6 vs 24.4, P less than .05). There was no significant improvement in blood gas values, fractional inspiratory oxygen, or ventilator settings during muscle relaxation. Pancuronium reduced periods of nonoptimal oxygenation and elevated intracranial pressure and may therefore help to decrease adverse sequelae for the low-birth-weight, ventilated neonate.

Pancuronium blood level monitoring in patients with tetanus.

Overdosage of muscle relaxant has been given as a possible explanation for the hypotensive episodes occurring during the management of tetanus. The aim of the present work was to study the pharmacokinetics of pancuronium during long term infusion. Pancuronium was administered to eight patients with severe tetanus for a period varying from 8 to 24 days. The concentration of pancuronium was measured daily in plasma and urine using a fluorimetric method. The plasma concentration varied from 0.27 to 0.48 microgram/ml. No tendency to accumulation was observed. The plasma concentration fell rapidly below the level associated with muscle relaxation when pancuronium was discontinued. This absence of accumulation can be explained by a rapid elimination of pancuronium through the kidney according to a process of ultrafiltration.

Respiratory mechanics by least squares fitting in mechanically ventilated patients: applications during paralysis and during pressure support ventilation.

OBJECTIVE: To evaluate a least squares fitting technique for the purpose of measuring total respiratory compliance (Crs) and resistance (Rrs) in patients submitted to partial ventilatory support, without the need for esophageal pressure measurement. DESIGN: Prospective, randomized study. SETTING: A general ICU of a University Hospital. PATIENTS: 11 patients in acute respiratory failure, intubated and assisted by pressure support ventilation (PSV). INTERVENTIONS: Patients were ventilated at 4 different levels of pressure support. At the end of the study, they were paralyzed for diagnostic reasons and submitted to volume controlled ventilation (CMV). MEASUREMENTS AND RESULTS: A least squares fitting (LSF) method was applied to measure Crs and Rrs at different levels of pressure support as well as in CMV. Crs and Rrs calculated by the LSF method were compared to reference values which were obtained in PSV by measurement of esophageal pressure, and in CMV by the application of the constant flow, end-inspiratory occlusion method. Inspiratory activity was measured by P0.1. In CMV, Crs and Rrs measured by the LSF method are close to quasistatic compliance (-1.5 +/- 1.5 ml/cmH2O) and to the mean value of minimum and maximum end-inspiratory resistance (+0.9 +/- 2.5 cmH2O/(l/s)). Applied during PSV, the LSF method leads to gross underestimation of Rrs (-10.4 +/- 2.3 cmH2O/(l/s)) and overestimation of Crs (+35.2 +/- 33 ml/cmH2O) whenever the set pressure support level is low and the activity of the respiratory muscles is high (P0.1 was 4.6 +/- 3.1 cmH2O). However, satisfactory estimations of Crs and Rrs by the LSF method were obtained at increased pressure support levels, resulting in a mean error of -0.4 +/- 6 ml/cmH2O and -2.8 +/- 1.5 cmH2O/(l/s), respectively. This condition was coincident with a P0.1 of 1.6 +/- 0.7 cmH2O. CONCLUSION: The LSF method allows non-invasive evaluation of respiratory mechanics during PSV, provided that a near-relaxation condition is obtained by means of an adequately increased pressure support level. The measurement of P0.1 may be helpful for titrating the pressure support in order to obtain the condition of near-relaxation.

Management of severe cerebral edema in the metabolic encephalopathy of Reye-Johnson syndrome.

Fifteen critically ill children with the diagnosis of Reye-Johnson syndrome were treated with techniques developed to maintain adequate cerebral perfusion pressure and levels of circulating blood glucose. One child died, three sustained neurological deficit, and nine children (70%) recovered without significant neurological dysfunction. The technique developed during the period these children were treated, the indications for their use, and factors that can interfere with maintaining adequate cerebral perfusion in patients with increased intracranial pressure from metabolic encephalopathy are described. The results suggest that neurological damage in this syndrome results from neuronal injury secondary to inadequate cerebral perfusion and/or hypoglycemia, and that neurological dysfunction like hepatic dysfunction should produce minimal mortality and morbidity if cerebral perfusion and adequate levels of circulating blood glucose are sustained during the period of increased intracranial pressure and liver failure.

Monitoring of liver oxygenation during neuroleptanalgesia in the dog.

In an animal study (7 mongrel dogs) the effects of neuroleptanalgesia (NLA) and combinations of NLA with nitrous oxide (N2O) and isoflurane on the macro- and microcirculation of the liver were investigated. Measurements were made in three steps. After NLA alone the dogs were supplementarily ventilated with nitrous oxide/oxygen at a ratio of 2:1. During the last step, 1 MAC isoflurane was added to the inspired gas. From the portal vein, arterial and mixed-venous systems' hemodynamic parameters, blood gases, and acid-base balance were recorded. As a parameter of oxygenation the tissue PO2 of the liver was measured with a multiwire surface electrode. During NLA stable hemodynamic conditions and a balanced acid-base status were observed. The nitrous oxide combination resulted in an increase of the mean pulmonary artery pressure of 16%. The addition of isoflurane had a negative inotropic effect: The heart index decreased to 74% of the starting value and the total peripheral resistance (TPR) increased by 27%. The summarized PO2 histograms under NLA and NLA/N2O showed arithmetic mean values of 34.1 and 35.2 mm Hg, respectively. The addition of isoflurane resulted in a left shift and a decrease of the mean value to 28.6 mm Hg. This histogram corresponds exactly to the oxygen pressure distribution in the dog liver during piritramide basic anesthesia. It seems that NLA and the combination of NLA/N2O increase the liver perfusion with a higher portal-venous and tissue PO2. This effect can be explained only by a massive change of visceral circulation. It is canceled by the addition of isoflurane.

Clinical evaluation of the Datex 221 neuromuscular transmission monitor for recording posttetanic electromyographic responses.

The assessment of deep neuromuscular blockade produced by nondepolarizing neuromuscular blocking agents is not possible with the conventional use of the Datex NMT-221 "relaxograph" (Datex NMT-221 monitor, Datex Instrumentarium, Helsinki, Finland), an otherwise useful electromyographic (EMG) monitoring device. A method whereby the relaxograph can be adapted to quantitatively measure posttetanic responses is described here. In anesthetized adult patients, neuromuscular blockade was monitored simultaneously on both hands with two relaxographs. On one hand, EMG responses of hypothenar muscles to the built-in 1/20-second sequence of train-of-four stimuli of the monitor were used. On the other hand, similar recordings were made with the addition of periodically superimposed supramaximal tetanic stimuli of 100 Hz to the ulnar nerve. Neuromuscular block was provided with pancuronium. The time courses of the spontaneous recovery of the first of the train-of-four EMG responses were compared in the stimulated and control arms. At the end of the surgery, the neuromuscular block was pharmacologically reversed with atropine and neostigmine. If no tetanic stimuli were applied, the EMG responses were identical in both arms during the spontaneous recovery from the neuromuscular blockade. If tetanic stimuli were applied every 4 or 7 minutes, the rate of recovery in the stimulated hand usually exceeded that of the control hand. However, no significant difference was observed in the recovery rate when the tetanic stimuli were spaced at 15-minute intervals. Pharmacologic reversal by atropine and neostigmine was found to be identical in all patient groups. The author concludes that the Datex relaxograph is suitable for the quantitative assessment of profound surgical neuromuscular blockade with the described modification.

[Maintenance doses of vecuronium and pancuronium during hypothermic cardiopulmonary bypass].

In 31 patients undergoing coronary artery bypass grafting, we investigated the maintenance doses of pancuronium and vecuronium during hypothermic cardiopulmonary bypass. For all patients, the height of the first twitch of the train-of-four (T1) was measured with evoked electromyogram. During operation, T1 was kept from 5 to 15 per cent of control. Infusion doses of both muscle relaxants were controlled with a personal computer. During hypothermic cardiopulmonary bypass (body temperature 28 degrees C), requirement of both muscle relaxants decreased for about 90 per cent compared with pre bypass values. We consider that the prolongation of neuromuscular blockade is attributable to hypothermia rather than to other factors of cardiopulmonary bypass. After rewarming, maintenance dose of vecuronium remained about a half of the dose required in pre-bypass period. It suggests that elimination of vecuronium from liver and kidney is hindered not only during hypothermia but also after rewarming.

[Is it necessary to discontinue captopril before heart surgery?]. / Faut-il arrêter le captopril avant l'opération en chirurgie cardiaque?

Interaction between kininase II and anaesthesia is not well described. Twenty two patients treated by kininase II for congestive heart failure are studied during anaesthesia for cardiovascular surgery. A first group of seventeen homogeneous hemodynamic data are reported. High cardiac index contrasts with severe clinical cardiac failure. A second group of inhomogeneous patients are separately described. Vasoconstrictor can be codified in the situation of low systemic resistance with high cardiac index. Preoperative treatment can be continued, under requirement of hemodynamic monitoring.

Neuromuscular blockade in cardiac surgery: an update for clinicians.

There have been great advancements in cardiac surgery over the last two decades; the widespread use of off-pump aortocoronary bypass surgery, minimally invasive cardiac surgery, and robotic surgery have also changed the face of cardiac anaesthesia. The concept of "Fast-track anaesthesia" demands the use of nondepolarising neuromuscular blocking drugs with short duration of action, combining the ability to provide (if necessary) sufficiently profound neuromuscular blockade during surgery and immediate re-establishment of normal neuromuscular transmission at the end of surgery. Postoperative residual muscle paralysis is one of the major hurdles for immediate or early extubation after cardiac surgery. Nondepolarising neuromuscular blocking drugs for cardiac surgery should therefore be easy to titrate, of rapid onset and short duration of action with a pathway of elimination independent from hepatic or renal dysfunction, and should equally not affect haemodynamic stability. The difference between repetitive bolus application and continuous infusion is outlined in this review, with the pharmacodynamic and pharmacokinetic characteristics of vecuronium, pancuronium, rocuronium, and cisatracurium. Kinemyography and acceleromyography are the most important currently used neuromuscular monitoring methods. Whereas monitoring at the adductor pollicis muscle is appropriate at the end of surgery, monitoring of the corrugator supercilii muscle better reflects neuromuscular blockade at more central, profound muscles, such as the diaphragm, larynx, or thoraco-abdominal muscles. In conclusion, cisatracurium or rocuronium is recommended for neuromuscular blockade in modern cardiac surgery.

Influence of moderate hypothermia on posterior tibial nerve somatosensory evoked potentials.

Posterior tibial nerve somatosensory evoked potentials (PTN-SSEP) were recorded in eight patients during cardiac surgery with cardiopulmonary bypass and moderate hypothermia (25-28 degrees C). There was no correlation between changes in amplitude and temperature; however, latencies of potentials recorded over the tibial nerve in the popliteal fossa, the lumbar spinal cord, and the cortex increased linearly as temperature decreased. Latency changes correlated well with nasopharyngeal temperature, but only poorly with rectal and lower limb muscle temperatures. During perioperative monitoring of spinal cord function by means of PTN-SSEP, an increase of the first positive cortical peak (P1) greater than 3 msec is considered an indication for intervention. In this study P1 prolonged 1.15 msec/degree C (r = 0.89, P less than 0.001). This implies that a temperature decrease of 2-3 degrees C may prolong P1 latency by more than 3 msec.