Resuscitation with lipid, epinephrine, or both in levobupivacaine-induced cardiac toxicity in newborn piglets.

BACKGROUND: The optimal dosing regimens of lipid emulsion, epinephrine, or both are not yet determined in neonates in cases of local anaesthetic systemic toxicity (LAST). METHODS: Newborn piglets received levobupivacaine until cardiovascular collapse occurred. Standard cardiopulmonary resuscitation was started and electrocardiogram (ECG) was monitored for ventricular tachycardia, fibrillation, or QRS prolongation. Piglets were then randomly allocated to four groups: control (saline), Intralipid(®) alone, epinephrine alone, or a combination of Intralipd plus epinephrine. Resuscitation continued for 30 min or until there was a return of spontaneous circulation (ROSC) accompanied by a mean arterial pressure at or superior to the baseline pressure and normal sinus rhythm for a period of 30 min. RESULTS: ROSC was achieved in only one of the control piglets compared with most of the treated piglets. Mortality was not significantly different between the three treatment groups, but was significantly lower in all the treatment groups compared with control. The number of ECG abnormalities was zero in the Intralipid only group, but 14 and 17, respectively, in the epinephrine and epinephrine plus lipid groups (P<0.05). CONCLUSIONS: Lipid emulsion with or without epinephrine, or epinephrine alone were equally effective in achieving a return to spontaneous circulation in this model of LAST. Epinephrine alone or in combination with lipid was associated with an increased number of ECG abnormalities compared with lipid emulsion alone.

Chronic intrathecal baclofen in severely disabling spasticity: selection, clinical assessment and long-term benefit.

Flexor and extensor spasms associated with severe spasticity frequently cause pain and suffering in neurologically impaired patients, and greatly interfere with comfort and activities. When high doses of oral medications are necessary to keep the symptoms under control and are poorly tolerated, the long-term spinal-selective intrathecal infusion of baclofen by means of implanted drug pump and catheter is a safe, efficient and reversible alternative to destructive surgical procedures. Between September 1991 and March 1995, intrathecal baclofen was infused in 18 selected patients out of a series of 42 severely disabled spastic cases. We report here our preliminary experience with the criteria of selection, the initial intrathecal bolus test and the long-term benefit of the selected patients. Our results confirm the dramatic immediate and long-term benefit reported in other series. After a period of treatment of 1 to 42 months, 13 patients had a complete disappearance of their spastic symptoms without any oral treatment, one patient kept unchanged clonus despite the use of low-dose oral treatment and another one a severe, not improved dysuria although in both of them hypertonia and spasms were abolished. Finally, 2 patients had important joint stiffness slightly impairing the benefit from the treatment. None of the 18 patients had central side-effects related to baclofen. With time, a slight increase in daily dose (inferior to 10%) was necessary in most patients.

Psychological factors in the causation of pressure sores: case reports.

A high incidence of re-admissions to a spinal injuries unit by a small number of patients suffering from multiple pressure sores is described. The study shows an increased association of skin fragility and poor healing with an altered psychological behaviour. This combination of vulnerability to recurrent pressure sores in association with the pathological intellectual debility is described as 'ectodermic syndrome'. This restricts the eventual rehabilitative outcome.

Two therapeutic experiments on stubborn pain in spinal cord lesions: coupling melitracen-flupenthixol and the transcutaneous nerve stimulation [proceedings].

A drug combination was used against sub-lesional pain with some good results. Transcutaneous stimulation was used in three cases of pain in the roots without result.

Evolution of post-traumatic cervical syringomyelia: case report.

A patient with complete post-traumatic paraplegia below T6 developed urinary problems and late secondary syringolmyelia. The concordance between the appearance of micturition difficulties and the first sensory symptoms leads us to discuss the rôle of important and repeated efforts to obtain reflex micturition, during the development of post-traumatic syringomyelia.

Respiratory mechanics in quadriplegia. The respiratory function of the intercostal muscles.

Pulmonary mechanics and inspiratory muscle pressures were studied in relation to electromyograms (EMG) of the respiratory muscles in 10 chronic quadriplegic patients . Transdiaphragmatic pressures at maximal inflation were normal, but minimal pleural pressures at functional residual capacity (FRC) were reduced to about one half the normal values. On the basis of the parasternal intercostal EMG results, 2 groups were defined. In 8 patients (Group I), no electromyographic activity was found in the intercostal muscles, even during large inspiratory maneuvers. In 2 patients (Group II), both intercostal and diaphragmatic activities were recorded during inspiration, and intercostal EMG activity increased with increasing inspiratory volume. Group 1 patients had reduced FRC, transpulmonary pressure at FRC, and static expiratory compliance; therefore, the pressure-volume curves of the lungs resembled those obtained in patients with generalized weakness of the respiratory muscles. Specific compliance was normal in each patient, suggesting that the low compliance resulted in large part from the collapse of air spaces. Group 2 patients had FRC, transpulmonary pressure at FRC, and lung compliance values within normal limits. We concluded that longstanding paralysis of intercostal muscles causes marked alterations in the elastic properties of the lungs and reduces the passive (outward) recoil of the chest wall. These findings suggested that the intercostal muscles normally stabilize the chest wall and prevent lung collapse. Moreover, intercostal surface EMG recordings may help to identify tetraplegic patients who may be at risk of developing respiratory failure during rather minor insults to the respiratory system.

Mechanism of active expiration in tetraplegic subjects.

Traumatic tetraplegia produces paralysis of all the well-recognized muscles of expiration. Yet, tetraplegic subjects usually have a small expiratory reserve volume on spirographic examination. To understand the mechanism that enables these patients to empty their lungs actively, we studied the pattern of chest-wall motion during voluntary expiration. We found negligible changes in abdominal dimension, but all subjects had a marked and reproducible decrease in the dimension of the upper rib cage. Electrical measurements established that the subjects had active use of the clavicular portion of the pectoralis major, and changing the orientation of these muscle fibers by maintaining the shoulders in abduction reduced their expiratory reserve volume by about 60 percent (P less than 0.001). We therefore conclude that the clavicular portion of the pectoralis major plays a crucial part in the mechanism of active expiration in tetraplegic subjects. Training of this muscle bundle could, by increasing its strength and endurance, improve the effectiveness of coughing in such subjects and perhaps diminish the prevalence of bronchopulmonary infections.

Evaluation of the use of Urocath-Gel catheters for intermittent self-catheterization by male patients using conventional catheters for a long time.

STUDY DESIGN: Prospective study of intermittent self-catheterization (CIC) with change from conventional catheter to low-friction Urocath-Gel catheter. OBJECTIVES: To evaluate if such catheters are well accepted and to evaluate their practical use. METHODS: Thirty-nine male patients, between 19 and 74 years old, performing clean intermittent self-catheterization with conventional catheters for a neuropathic bladder for many years were included in this study after written informed consent. Exclusion criteria were clinical urinary tract infection, acute infection of urethra, prostate or epididymis, untreated urethral strictures and false passages or severe urethral bleeding occurring within the last month. During 1 month they changed to the use of the Urocath-Gel catheter. Complications were noted. Satisfaction was evaluated by a visual analogue scale and by questioning. RESULTS: Four patients did not complete the study, two for side effects, two for difficulties with the catheterization technique. Time needed for CIC was not different with both techniques. Difficult introduction or difficult retreat of the catheter were not different in frequency. Impossibility to introduce the catheter was less frequent. Urethritis and urethral bleeding were less frequent than during the use of conventional catheters. Satisfaction was better with the low friction catheters. Negative satisfaction was mainly related to the availability and the use of water to lubricate the catheter, difficulty of manipulation and fear for cost. CONCLUSION: The hydrophilic catheter Urocath-Gel proved as easy to use as conventional catheters but was better tolerated. Satisfaction was better especially in patients who experienced problems with conventional catheters. Some patients were unsatisfied for reasons of practical use or for economical reasons.

Evidence of dynamic airway compression during cough in tetraplegic patients.

Although all the well-recognized muscles of expiration are paralyzed after traumatic transection of the lower cervical cord, tetraplegic subjects can still empty their lungs actively by contracting the clavicular portion of the pectoralis major. It is not known, however, whether contraction of this muscle bundle may raise pleural pressure enough to cause dynamic compression of the intrathoracic airways, which is critical for the production of an effective cough. To investigate this question, we measured expiratory flow rate and esophageal pressure during a series of forced expiratory vital capacity (VC) maneuvers in twelve subjects with C5-8 traumatic tetraplegia and constructed isovolume-pressure flow (IVPF) curves. The curves were interpretable with certainty in nine patients. Three of them did not show any plateau of flow. On the other hand, six patients had clearcut plateaus of flow on all IVPF curves between 80-60 and 20% VC, suggesting they had dynamic airway compression. Videoendoscopic recordings in two patients confirmed trachea and main bronchi collapse during forced expiration and cough. We conclude, therefore, that contraction of the pectoralis major causes dynamic airway compression during expiratory efforts in a substantial proportion of tetraplegic subjects. Increasing the pressure-generating capacity of this muscle might thus improve the effectiveness of cough and reduce the prevalence of bronchopulmonary infections.

The effect of pectoralis muscle training in tetraplegic subjects.

We have previously shown that subjects with traumatic tetraplegia use the clavicular portion of the pectoralis major to expire actively. To determine if we could improve the expiratory function of these subjects, we studied six patients in whom the pectoralis major was trained by repetitive, strenuous, isometric contractions for 6 wk. Six patients receiving conventional respiratory rehabilitation served as control subjects. Training of the pectoralis major produced marked increases in the maximal isometric muscle strength (mean +/- SE: 54.6 +/- 5.8%; p less than 0.005) and in expiratory reserve volume (46.6 +/- 9.9%; p less than 0.005). Functional residual capacity did not change, such that residual volume decreased by 14.1 +/- 2.9% (p less than 0.005). In contrast, the control patients did not develop any significant alterations. We conclude that unlike conventional rehabilitation, training the pectoralis major for strength improves expiratory function in tetraplegic subjects. Therefore, training of this muscle should increase the effectiveness of coughing and might reduce the prevalence of bronchopulmonary infections in such subjects.

Anaemia and marrow blood flow in the rat.

An increase in bone marrow blood flow has been previously described in anaemic rabbits and dogs. We examined the effect of haemorrhage and haemolysis in female Sprague-Dawley rats, with the hypothesis that high blood flow was related to hyperplasia of bone marrow tissue and that the increase would affect bone as well. Blood flow was measured in tibia and femur by the microspheres trapping method. Chronic anaemia was accompanied at day 32 by a marked increase (factor of 1.7-1.9) in blood flow to bone marrow and to bone. On the other hand, no increase in blood flow was observed in chronic compensated anaemia, showing that anaemia per se and not stimulation of erythropoiesis was responsible for the increase. We then explored the effect on blood flow of two factors associated with anaemia. Erythropoietin 4 U/d for 4 d failed to induce any increase in bone and marrow blood flow. Systemic hypoxia (76 mmHg for 3 d) reduced the fraction of cardiac output conveyed to bone and marrow by 40-50%, but this decrease was more than compensated by an increase in cardiac output. We conclude that neither erythropoietin nor low tissue pO2 is the direct cause for the increase in bone and marrow blood flow observed in anaemia.

Effects of abdominal strapping on forced expiration in tetraplegic patients.

Patients with traumatic transection of the lower segments of the cervical cord contract the clavicular portion of the pectoralis major during forced expiration and cough, and the rise in intrathoracic pressure resulting from this contraction produces dynamic airway compression in many patients. Because the abdominal muscles are paralyzed, however, there is paradoxical expansion of the abdomen, which may reduce the rise in intrathoracic pressure and the degree of airway collapse. To evaluate the magnitude of this effect, we measured expiratory flow rate (Vexp) and esophageal pressure (Pes) during a series of forced expiratory vital capacity maneuvers and constructed isovolume-pressure flow (IVPF) curves before and after abdominal strapping in eight C5-8 tetraplegic subjects. Strapping produced small and inconsistent changes in maximal Vexp and Pes and resulted in the development of small flow plateaus in only four patients. In tetraplegic subjects, abdominal strapping thus has small effects on forced expiration and is unlikely, therefore, to improve the efficiency of cough.

Longitudinal study of the bone mineral content and of soft tissue composition after spinal cord section.

We present the results of a 1 year longitudinal study of bone mineral measurements and soft tissue composition in supra- and infra-lesional areas of 31 patients with a spinal cord injury (level D2-L3). Like others, we observed a rapid decrease of BMC in the paralysed areas, of approximately 4%/month during the first year in areas rich in trabecular bone and of approximately 2%/month in areas containing mainly compact bone. Lean soft tissue mass (muscle mass) decreases dramatically during the first months post injury in the legs, while fat content tends to increase. Though lean mass is better maintained in patients who develop spasticity, the evolution of BMC does not differ significantly between the groups of flaccid and spastic patients. In patients with partial or complete neurological recovery, a deficit in BMC of approximately 10% with regards to the initial value is still observed at 1 year in the lower limbs. The lean mass of the upper limbs increases early after the cord injury, because of intensive rehabilitation. No significant change in BMC was observed in the supra-lesional areas. These data confirm the rapid loss of bone in the paralysed areas of paraplegic patients, which occurs independently of the presence of spontaneous muscle activity or of passive verticalisation. In patients with recovery, BMC does not return to pre-injury values within 1 year. Thus, there would be an interest in preventing bone loss early in the course of the disease.

Longitudinal study of calcium and bone metabolism in paraplegic patients.

A longitudinal study of bone and calcium metabolism in 28 patients with spinal chord lesion shows an enhancement of bone calcium accretion, generalized to the whole skeleton. The bone calcium turnover rate is more increased in the non-paralysed area during the first 2 months.

Chest wall stiffness in patients with chronic respiratory muscle weakness.

Using the weighted spirometer technique we studied chest wall compliance (Cw) in 16 nonobese patients with chronic weakness of the respiratory muscles and 20 healthy control subjects. In order to evaluate the validity of the technique, while Cw was being measured, we monitored thoracoabdominal configuration with 2 pairs of linearized magnetometers and electrical activity of the external oblique with a concentric needle electrode in 3 healthy subjects and 4 patients; in addition, we recorded in 3 subjects the electrical activity from the intercostal muscles and diaphragm throughout the procedure. The method was reproducible within 5.8% and provided Cw values that compared well with those yielded by the relaxation technique. In each subject, the weight-induced shifts in end-expiratory lung volume showed a very good linear correlation with the changes in transrespiratory pressure at end-expiration (r greater than or equal to 0.91). In addition, in none of the subjects tested did the electromyograms reveal any intercostal, diaphragmatic, or abdominal muscle activity at end-expiration, nor did the end-expiratory level ever show a significant departure from the relaxed thoracoabdominal configuration, thus suggesting adequate respiratory muscle relaxation. The reduction in inspiratory muscle force in the patients ranged from 17 to 94% of predicted (mean +/- SE, 43 +/- 6). The decrease in vital capacity, total lung capacity, and functional residual capacity averaged 59, 34, and 15% of predicted, respectively. Both the patient and the control groups showed a large interindividual variability regarding Cw. It varied from 0.117 to 0.258 L/cm H2O (mean +/- SE, 0.162 +/- 0.012) in the patients and from 0.163 to 0.366 L/cm H2O (mean +/- SE, 0.248 +/- 0.013) in the healthy subjects.(ABSTRACT TRUNCATED AT 250 WORDS)

Lung volume restriction in patients with chronic respiratory muscle weakness: the role of microatelectasis.

BACKGROUND: It is well established that patients with longstanding weakness of the respiratory muscles have a reduction in lung distensibility. Although this occurs in most patients without any radiographic changes suggesting parenchymal lung disease, it has been attributed to the development of microatelectasis. METHODS: A high resolution computed tomographic (CT) scanner was used in eight patients with traumatic tetraplegia and six patients with generalised neuromuscular disorders to look for areas of atelectasis. With the patient in the supine posture scans of 1 mm thickness were obtained at total lung capacity at intervals of 1 cm from the apex to the base of the lung. RESULTS: Vital capacity, total lung capacity, and inspiratory muscle strength were reduced to a mean of 59.5%, 73.9%, and 51.1% of predicted values, respectively. Static expiratory lung compliance was decreased in 12 of the 14 patients and averaged 69.1% of the predicted value. The CT scans revealed only small areas of atelectasis in one tetraplegic patient and in one patient with a generalised neuromuscular disorder; no parenchymal abnormality was seen in the other 12 patients. CONCLUSIONS: In many patients with chronic weakness of the respiratory muscles the reduced lung distensibility does not appear to be caused by microatelectasis. It might be related to alterations in elasticity of the lung tissue.