Pharmacokinetics of bupivacaine following intraoperative intercostal nerve block in neonates and in infants aged less than 6 months

Pharmacokinetics and blood concentrations of bupivacaine were studied after intercostal nerve blocks were performed intraoperatively using 1.5 mg.kg-1 in 11 neonates (age 0-28 days) and 11 infants between age 1 and 6 months. The study aimed to provide pharmacokinetic data that are limited in these age groups, and to identify any adverse effects of intercostal nerve block in infancy. Arterial blood samples were taken at 0, 5, 10, 15, 20, 30, 60, 120, 240, and 360 min. Whole blood bupivacaine was assayed by high-performance liquid chromatography. Peak blood concentrations were attained within 10 min in 18 of 22 subjects, and were 087 micrograms.ml-1 [corrected] +/- 0.56 micrograms.ml-1 (mean and SD) and 0.91 +/- 0.27 micrograms.ml-1 in neonates and infants, respectively. Pharmacokinetic variables in the two groups included elimination half-life (t1/2 beta): 132 +/- 59 min and 102 +/- 39 min; steady-state volume of distribution (Vdss): 2.56 +/- 0.76 l.kg-1 and 2.17 +/- 0.17 l.kg-1; and total body clearance (Clt): 16.93 +/- 9.32 ml.min-1.kg-1 and 15.71 +/- 6.99 ml.min-1.kg-1. There was no statistically significant difference between neonates and infants with regard to any of these parameters. Patients were further divided into those with acyanotic and cyanotic disease. Cyanotic infants were significantly heavier than acyanotic infants (P less than 0.05), but no other differences were demonstrated. No adverse effects resulting from the technique were identified.(ABSTRACT TRUNCATED AT 250 WORDS)

Two epithelioid malignant schwannomas in a patient with neurofibromatosis. Cytology, histology and DNA-flow-cytometry

Cytological, histological and DNA-ploidy findings of 2 epithelioid malignant schwannomas arising in a patient with von Recklinghausen's neurofibromatosis are described. In both primary tumors, i.e. in the thigh and in the thoracic wall, origin from a neurofibromatous nerve could be established. Within 2 years after the manifestation of the first malignant tumor the patient died of widely metastasized disease. DNA-flow cytometry of several neurofibromas revealed diploid stemlines, but both malignant primary tumors and a lung metastasis appeared to be aneuploid. Presumably, the primary tumors also contained cell populations with a diploid stem line.

[Continuous intercostal nerve block for chronic pain]

21 ambulatory patients with acute or chronic pain localized to the chest, were treated successfully by continuous intercostal block. They included 6 women and 15 men, aged 39-70. Treatment was initiated in the outpatient clinic and continued at home for usually 5-6 days. Between 15-20 ml of 0.5% marcaine were continuously injected over the course of 6-12 hours through a catheter introduced into the intercostal space by a Touhy needle. 76% of the patients had substantial relief of pain during the block and required only minimal systemic medication. During a 3 month follow-up after cessation of the block, up to 65% were still pain-free. Results were poor or only fair in those with malignancy and long-standing intercostal neuralgias. There were no serious side-effects during treatment. This method is an important new tool in the treatment of pain.

Thoracic paravertebral block: a method of pain control

The adverse effects of pain on acutely ill or traumatized patients are well documented. A variety of pain-relieving techniques are now available to meet the varied requirements for pain relief. This paper presents the results of a single, large-volume injection of bupivacaine 0.5% in the thoracic paravertebral space, achieving pain relief over several thoracic dermatomes in patients with respiratory compromise secondary to thoracic or upper abdominal injury. The block proved quick and simple to perform, with excellent clinical results of long duration and virtually no complications. Although not previously described, this single, large-volume injection approach to achieving an extensive thoracic paravertebral block may well become an important pain management technique in appropriate patients.

Intercostal blockade and pulmonary function after cholecystectomy

Sixty-six patients undergoing cholecystectomy were randomly allocated to receive either intercostal blockade with bupivacaine supplemented with papaveretum or papaveretum alone for postoperative analgesia. Both groups were similar regarding distribution of sex, age, and weight. These two groups were compared. Patients who did not have intercostal blockade required postoperative analgesia sooner. There was no significant difference, however, in the total consumption of papaveretum. Both groups experienced similar degrees of pain, and there were no differences in postoperative pulmonary function. We conclude that although single intercostal blockade is an effective analgesic, it does not improve pain relief and does not improve pulmonary function after cholecystectomy when compared with a regimen of on-demand, intramuscularly administered papaveretum.

Effect of intercostal nerve blockade on respiratory mechanics and CO2 chemosensitivity at rest and exercise

Lower intercostal and abdominal muscles interact with other respiratory muscles to produce inspiration as well as expiration. Intercostal nerve blockade from T6-T12 was produced in seven healthy males to study its effect on: 1) supine pulmonary function, 2) inspiratory effort, 3) hypercapnic ventilatory response, including mouth occlusion pressures with and without an expiratory load, and 4) ventilation during progressive exercise on a cycle ergometer. Studies during control and blocked states were performed on different days. Lower chest and abdominal wall paralysis was documented with electromyography. Findings include a minimal decrease in peak expiratory flows with intercostal blockade (P = 0.02), but no other changes in supine resting pulmonary function tests, inspiratory effort, or hypercapnic ventilatory response slopes. Minute ventilation, respiratory rate, and VT/TI during exercise were also minimally increased, indicating an increase in the drive to breathe, which was unrelated to a change in metabolic rate. During exercise, total time to exhaustion was decreased following intercostal nerve blockade. Bilateral intercostal nerve blockade produced minimal decreases in peak expiratory flow at rest in supine subjects. During seated exercise, there was a slight increase in respiratory drive, probably due to minor alterations in the mechanics of breathing induced by intercostal blockade. The authors conclude that, in healthy young subjects, intercostal nerve blockade does not exert a clinically significant adverse affect on pulmonary mechanics and that ventilatory function is well-maintained even at extremes of ventilatory demand.

A case of isolated paralysis of serratus anterior

The authors present a case of isolated paralysis of the serratus anterior due to compression of the long thoracic nerve by a cervical rib. The clinical and diagnostic features are described. Removal of the vertical rib resulted in complete functional recovery of the muscle involved.

Continuous intercostal nerve block for pain relief after thoracotomy

Others have demonstrated the effectiveness of intercostal analgesia with bupivacaine hydrochloride (Marcain Plain; Astra). We present a greatly simplified method of effecting this. Our method is dependent on an intact pleura. To date, we have utilized this technique in 81 patients. Seventy-five (92.6%) required no additional analgesic in the first 24 hours following operation and 66 (81.5%), in the subsequent four days. Only 2 patients had postoperative pulmonary complications. No complication related either to the procedure or to the infusion of bupivacaine occurred. The technique as described here is a safe and reliable method of providing analgesia without any side effects after thoracotomy.

The control of post-thoracotomy pain. A comparative evaluation of thoracic epidural fentanyl infusions and cryo-analgesia

This is a comparative study of two methods to relieve postoperative thoracotomy pain. Continuous thoracic epidural infusion of fentanyl produced superior analgesia when compared with cryo-analgesia of the relevant thoracic nerves. Linear analogue pain scores were consistently lower in the epidural group reaching significance (p less than 0.05) at 32 and 40 hours after operation. All 36 patients in the cryo-analgesia group required additional analgesia, while 12 out of the 32 patients in the epidural group did not. This difference was significant at p less than 0.001. Respiratory and cardiovascular measurements were similar in both groups and the only side effect attributable to the epidural fentanyl was itching but this was not a problem.

Low volume intercostal injection. A comparative study in patients and cadavers

This study compared the spread of 3 ml of a solution of bupivacaine-methylene blue in the intercostal space of patients and cadavers. There were 51 successful injections in each group which demonstrated in 86% of patient injections and 84% of cadaver injections that spread was confined to one intercostal space. Spread was more extensive in cadavers, probably as a result of autolysis. It would therefore still appear necessary, when low volumes of local anaesthetic are used, to block each intercostal nerve individually.

Intercostal nerve blockade producing analgesia after appendicectomy

Intercostal nerve blockade of the 10th, 11th and 12th thoracic nerves on the right side was compared with i.m. papaveretum as analgesia after appendicectomy. Patients with intercostal nerve blockade had significantly less pain at 0, 4, 8 and 12 h after operation and required less papaveretum (mean 0.26 mg kg-1/24 h) compared with the controls (mean 0.62 mg kg-1/24 h). There were no complications in either group. Intercostal nerve blockade may provide better quality analgesia following appendicectomy than i.m. papaveretum alone.

The treatment of intercostal-brachial neuromas by posterior intercostal neurectomies. A case report

The development of sensory neuromas in a postoperative field is a recognized and undesirable complication. Neuroma formation can impair patient cooperation and postoperative function. Treatment efforts are frequently unrewarding and may contribute to the patient's frustration. Intercostal-brachial neuromas which develop following first rib resections are representative of this problem. Posterior intercostal neurectomy may provide an alternative treatment modality.

Preoperative intercostal nerve block: effect on the endocrine metabolic response to surgery

The plasma cortisol and glucose responses to cholecystectomy were studied in 20 healthy patients. Ten patients received preoperative intercostal nerve blocks of the 6th to 12th nerves bilaterally using 0.5% bupivacaine with adrenaline 250 micrograms. The control group had the same quantity of adrenaline infiltrated into the intercostal space. Both groups had general anaesthesia with endotracheal intubation and controlled ventilation. In the non-blocked group, the mean cortisol concentration increased from a control value of 182.5 nmol litre-1 to a peak of 686.2 nmol litre-1 at 5.5 h after incision. In the blocked group the baseline serum cortisol concentration was 283.8 nmol litre-1 and it increased to a similar peak at 5.5 h. There were no significant differences between groups. The baseline plasma glucose concentration was also higher in the blocked group (4.45 mmol litre-1 compared with 3.94 mmol litre-1), but after a brief increase following the performance of the block decreased to only 14% above control values. The unblocked group exhibited substantial increase following the start of the surgery which continued for the duration of the study period to end at a mean of 6.48 mmol litre-1. These differences were significant (P less than 0.001). It is concluded that bilateral intercostal blocks may inhibit the glucose response to surgery, but have no effect on the cortisol response.

Effects of upper dorsal sympathectomy on esophageal motility in humans

To evaluate the role of the sympathetic nervous system in modulating esophageal motility, esophageal manometry was performed on two groups of patients who underwent upper dorsal sympathectomy for relief of palmar hyperhydrosis. In six patients sympathectomy was done by the supraclavicular approach, with removal of T2 and T3 ganglia. Manometry was performed before the operation and three weeks after it. In seven other patients sympathectomy was done by the axillary approach, with removal of T2-T4 ganglia. Manometry in this group was performed 28.4 +/- 22.4 months after the operation. Fifteen individuals with an intact sympathetic system served as controls. Manometric parameters evaluated were esophageal contraction amplitude and duration and lower esophageal sphincter pressure. The difference between the results obtained in the pre- and postoperative periods in the first group was not statistically significant. The differences between the two patient groups and between the patient groups and the control group were not statistically significant either. We conclude that upper dorsal sympathectomy does not affect esophageal motility in man.

[Cyriax's syndrome. A cause of diagnostic error in abdominal pains]

The slipping rib syndrome is characterized by upper abdominal pain due to irritation of the intercostal nerve by incomplete dislocation of the costal cartilage of the 8th, 9th, or 10th ribs. Twenty-three new cases are reported and the literature is reviewed. Diagnosis is only clinical. The pain is precipitated by movement and certain postures; it is faithfully reproduced by pressure on one particular point of the costal margin and is relieved by local injection of an anaesthetic. Pain from a slipping rib is usually attributed to visceral causes, which is a source of diagnostic errors.

Reduction of post-thoracotomy pain by cryotherapy of intercostal nerves

In a prospective study, 144 patients undergoing thoracotomy were randomized to two groups: In 71 cases cryoanalgesia was applied intraoperatively to the intercostal nerves above and below the incision to relieve postoperative pain, and 73 (control group) received bupivacaine-adrenaline intercostal blockade at the end of the operation. The amount of administered narcotic and mild analgesics, the visual analogue pain scores, the need for further intercostal blockade and the number of postoperative bronchoscopies to clear retained secretion were significantly less in the cryoanalgesia group than in the controls. There were no late nerve complications after cryoanalgesia, which is recommended for routine use in thoracotomy.

Use of a Doppler ultrasound stethoscope for intercostal nerve block

Two cases with rib injuries are reported where intercostal nerve block without rib palpation was safely and successfully performed on six separate occasions using a Doppler blood-flow detector ultrasound stethoscope. A third case studied by a radiologist using a pulsed Doppler flowmeter, determined the source of the Doppler signals as originating from the intercostal artery. The significance of these findings is discussed.

Intercostal block with cryotherapy

A retrospective survey of 70 patients treated from 1982 to 1984 for chronic intercostal pain with cryotherapy to the intercostal nerves is presented. The results with patients suffering from postherpetic neuralgia are so poor that the authors cannot recommend this form of treatment for this condition. The results with patients suffering from thoracic surgical scar pain are significantly better (P less than 0.005) and support the use of the cryoprobe for this condition.