Dose response of succinylcholine at the adductor pollicis of children with cerebral palsy during propofol and nitrous oxide anesthesia

Children with cerebral palsy may be resistant to paralysis induced by nondepolarizing neuromuscular blocking drugs. Potency of a bolus of succinylcholine in children with cerebral palsy has not been studied previously. Therefore, we measured the response of the adductor pollicis to succinylcholine in children with cerebral palsy anesthetized with propofol and nitrous oxide. Forty children between the ages of 2 and 10.2 yr with spastic quadriplegic cerebral palsy were randomly assigned to receive 100, 175, 250, or 375 micrograms/kg of succinylcholine during anesthesia with propofol and nitrous oxide. The ulnar nerve was stimulated with a train-of-four supramaximal stimulus every 10 s and the compound electromyogram of the adductor pollicis recorded by a Datex NMT monitor. Plasma cholinesterase activity was measured in all patients with three different substrates (propionylthiocholine, benzoylcholine, and succinylcholine). Dibucaine number was also determined using inhibition of benzoylcholine degradation. ED50 of succinylcholine was 146.8 micrograms/kg with 95% confidence intervals of 111.4-193.7 micrograms/kg. ED95 of succinylcholine was 360.5 micrograms with 95% confidence intervals of 273.3-475.5 micrograms/kg. We conclude that children with cerebral palsy are slightly sensitive to succinylcholine, but probably not sufficiently to be clinically important.

Loin pain-hematuria syndrome with a distinctive vascular lesion and alternative pathway complement activation

We describe a 48-year-old woman with loin pain-hematuria syndrome. Her renal abnormalities included conspicuous microaneurysmal and glomeruloid (plexiform) angiomatous changes. The deposition of both properdin and the C5b-9 complex, as well as the usual C3, in arterioles argues for complement activation. To our knowledge, neither of these features has been previously described. We speculate about the cause of loin pain-hematuria syndrome and note the uncommonness of this entity in the United States as opposed to Great Britain.

Responses to hemorrhagic arterial pressure reduction in different ischemic renal failure models

Renal blood flow (RBF) autoregulation has been found to be impaired in both norepinephrine (NE) and renal artery clamp (RAC) rat ischemic acute renal failure models. However, the decline in RBF at the normal lower limit of autoregulation is greater in NE-ARF. The present study was designed to determine if this difference in autoregulatory profiles has potential functional and morphologic significance. After demonstrating a fall in RBF to renal perfusion pressure reduction to 90 mm Hg that was twofold more in one week NE- than RAC-ARF (p < 0.001), separate rats of both ischemic ARF types with nearly identical levels of azotemia and glomerular filtration rate reduction and sham-ARF rats were subjected to four-hour controlled reduction in mean arterial pressure to 90 by transient phlebotomy at one week. On day 9, two days after mean arterial pressure reduction, blood urea nitrogen (BUN), serum creatinine (SCr) and creatinine clearance (CCr) showed continued improvement in RAC-ARF, but there were significant increases in BUN (46 +/- 22 to 72 +/- 10 mg/dl) and SCr (1.2 +/- 0.2 to 1.5 +/- 0.2 mg/dl) and a decline in CCr (0.434 +/- 0.127 to 0.334 +/- 0.079 ml/min) in the NE-ARF group (all P < 0.02). The mean sum of scores of morphologic indices of ARF was higher in NE- than RAC-ARF kidneys of rats sacrificed on day 9 but interstitial edema was the only individual index that was worse in NE-ARF.(ABSTRACT TRUNCATED AT 250 WORDS)

The dose-response relationship for hypoxic pulmonary vasoconstriction

In 12 pentobarbital anesthetized dogs the lungs were independently ventilated with a double piston ventilator. The right lung was ventilated throughout with 100% oxygen. Blood was drawn from the right atrium and pumped through a bubble oxygenator to a cannula in the ligated left main pulmonary artery. The pressures in the left main pulmonary artery and the left atrium were recorded during constant flow while the oxygen tension in the left lung alveolar gas and the perfusate were varied either to match each other (Protocol 1) or differ (Protocol 2) over the range from "zero" to "100%" oxygen. From the combined data a three dimensional response surface for hypoxic pulmonary vasoconstriction was derived. The maximum increase of pulmonary vascular resistance (r%PVRmax) was defined at a stimulus oxygen tension (PSO2) of 10 mmHg amounting to a 3.15 +/- (0.18)-fold increase of the vascular resistance on "100%" oxygen. The stimulus oxygen tension was shown to be PSO2 = PVO2(0.41) x PAO2(0.59) and the dose-response sigmoid for hypoxic pulmonary vasoconstriction in canine lungs was derived as r%PVRmax = 100 (PSO2(-2.616))/(6.683 x 10(-5) + PSO2(-2.616)) These results appear to reconcile observations from a number of laboratories and to be of quite general application.

Fracture of the spine in patients with ankylosis due to diffuse skeletal hyperostosis: clinical and imaging findings

OBJECTIVE

Only 12 patients with a fracture through a portion of the spine ankylosed by diffuse idiopathic skeletal hyperostosis have been reported. The purpose of this study was to determine the types of causative trauma, spinal sites at risk for fracture, complications mortality, diagnostic difficulties, and abnormalities identified only with special imaging studies in a group of 15 patients with this complication seen at our institution.

MATERIALS AND METHODS

The study included 15 patients with diffuse idiopathic skeletal hyperostosis who had a spinal fracture through an area of ankylosed spine. The criteria for diffuse idiopathic skeletal hyperostosis include flowing calcification or ossification along the anterolateral margin of at least four contiguous vertebral bodies; preservation of disk height in the involved areas; and absence of bony ankylosis of the apophyseal joint and erosion, sclerosis, or bony fusion of the sacroiliac joints. All spinal radiographs, tomograms, CT scans, and MR images obtained in these patients were reviewed to determine diagnostic difficulties, site and level of fracture, displacement of fractures, and extent of anatomic injury. The hospital charts of all patients were reviewed for history, physical examination, clinical status, treatment, and outcome.

RESULTS

Fourteen fractures of the cervical spine, one of the thoracic spine, and one of the lumbar spine occurred in 15 patients. Five fractures were caused by high-energy trauma and 11 fractures by low-energy, seemingly trivial injuries. The spinal fracture caused complete quadriplegia in seven patients, incomplete quadriplegia in one patient, complete paraplegia in two patients, a central cord syndrome in two patients, and no neurologic deficit in three patients. In two of three patients in whom fracture diagnosis was delayed, paraplegia developed during the delay. Three patients died within 1 week and three more died within 6 months after injury. CT and conventional tomography enabled diagnosis of posterior element fractures not seen on plain radiographs in five patients. All fractures healed, except those in the three patients who died within a week of injury.

CONCLUSION

Trivial trauma was the most common cause of fracture in the spine ankylosed by diffuse idiopathic skeletal hyperostosis. The severity of spinal cord injury in our patients was greater than in previous reports. We suggest that this may be a function of the relatively long segments of ankylosed spine (average, 16 vertebrae) in our patients providing a long lever arm for any traumatic force to act on. Patients with shorter ankylosed segments had less severe cord injuries. Delay in diagnosis of a fracture through an area of ankylosed spine associated with diffuse idiopathic skeletal hyperostosis was common if no neurologic deficit was present, and led to permanent paraplegia in two of three patients. CT and MR studies were useful in determining the anatomic abnormalities present, but were performed only in a limited number of patients.

Fibrogenic growth factors in the eosinophilia-myalgia syndrome and the toxic oil syndrome

BACKGROUND AND DESIGN

We sought to determine if growth factors of potential pathogenetic significance are deposited in the skin, muscle, and peripheral nerve lesions of eosinophilia-myalgia (EMS) and toxic oil syndrome. Immunohistochemical studies using affinity-purified peroxidase-conjugated antibodies to detect transforming growth factor-beta, platelet-derived growth factorAA and growth factorBB, fibroblast growth factor, epidermal growth factor, and interleukin 4 were performed on formalin-fixed, paraffin-embedded specimens. Seven skin biopsy specimens from EMS, six skin biopsy specimens from toxic oil syndrome, nine muscle biopsy specimens from EMS, and one sural nerve biopsy specimen from EMS were studied.

RESULTS

Growth factor staining was noted primarily in the epidermis and periappendageal locations of the dermis. The presence of TGF-beta and platelet-derived growth factorAA in the periappendageal dermis was significantly more prevalent in EMS than toxic oil syndrome (57% vs 0%). Prominent staining of transforming growth factor-beta was also present in the perimysial connective tissue of five (63%) of eight EMS muscle biopsy specimens and one sural nerve biopsy specimen.

CONCLUSIONS

These studies implicate transforming growth factor-beta and platelet-derived growth factorAA as potentially important cytokines in EMS and suggest that the pathogenesis of tissue fibrosis in EMS and toxic oil syndrome may be dependent on different growth factors.

Heterotopic ossification after hip and spine surgery in children with cerebral palsy

We made a retrospective review of 198 children with cerebral spasticity to determine development of heterotopic ossification. Of 61 children undergoing hip adduction lengthening, 21 had mild to moderate grades of heterotopic ossification. Only two of 132 patients who underwent spine fusions had developed heterotopic ossification, but in both it was severe, resulting in hip fusion. Two of five patients undergoing concomitant hip surgery and spine fusion developed heterotopic ossification of severe degree. The occurrence of heterotopic ossification after hip muscle surgery in children with cerebral spasticity is common but usually minor. Heterotopic ossification developing after spine fusion is rare but severe when it occurs, and concomitant hip and spine surgery causes frequent severe occurrences of heterotopic ossification.

Long-term follow-up of triple arthrodesis in patients with cerebral palsy

This study was a long-term retrospective review of patients with cerebral palsy (CP) who had triple arthrodeses as children before 1981. The medical records were reviewed, and the patients were requested to return for reevaluation, during which a radiograph, physical examination, and patient questionnaire were obtained. Twenty-four patients who had triple arthrodesis on 35 feet returned for evaluation. Twenty-three feet had planovalgus deformities and 12 equinovarus deformities. Mean age at operation was 14.2 years, with a mean follow-up of 17.8 years (range 11-45 years). Of the 24 patients questioned, 19 were satisfied and five were dissatisfied with their result. Nine patients had occasional pain; one patient reported frequent pain in one foot. Six patients had limited distance ambulation owing to their feet. Radiographic evaluation demonstrated that 43% of the feet had degenerative changes at the ankle joint. Four of six patients reported ambulatory limitation due to pain. Ankle joint range of motion (ROM) and degenerative arthritis were not correlated with pain, distance limitations, residual deformity, or patient satisfaction. Patient satisfaction was predominantly related to persistent pain, especially pain causing distance limitations in ambulation. Patient satisfaction was also strongly correlated with residual deformity. Persistent pain and distance limitation were also strongly correlated with residual planovalgus deformity.

Laparoscopic cholecystectomy in transplant patients

Acute cholecystitis is a serious condition in transplant patients and elective cholecystectomy is generally recommended when gallstones are found. We reviewed the results of laparoscopic cholecystectomy (LC) in 10 immunosuppressed transplant patients (6 heart, 4 kidney) and compared them to the results of open cholecystectomy performed in 26 transplant patients (14 heart, 11 kidney, 1 kidney/pancreas). The LC group had a 20% incidence of minor complication with no major complications and no deaths. The open-cholecystectomy group experienced 19% minor complications, 23% major complications, and 15% deaths. The average postoperative length of stay for the LC patients was 4.6 days (2 days for the 5 straightforward cases) as compared to 9.1 days after open cholecystectomy (4 days for the 13 straightforward open cases). Oral immunosuppression was stopped prior to operation but could be restarted within 29 hours after operation in the LC patients and 68 h in the open cases. The findings at LC were helpful in assessing whether acute cholecystitis and/or choledocholithiasis was the source of fever, liver-function abnormalities, or pancreatitis in these immunosuppressed transplant patients. We conclude that LC can be performed safely in transplant patients, but that in 10-20% of patients, the operation will be converted to an open procedure. The advantages of LC in these patients are a shorter hospitalization and less delay to resumption of preoperative oral immunotherapy than after open cholecystectomy.

Isometric exercise increases strength and does not produce sustained creatinine phosphokinase increases in a patient with polymyositis

A patient with active stable idiopathic polymyositis received a 4-week supervised right quadriceps and biceps isometric strengthening program. He demonstrated a significant increase in isometric peak torque without a sustained rise in creatinine phosphokinase (CPK). A significant decrease in postexercise CPK occurred at the end of the exercise program. We conclude a randomized clinical trial using a nonexercised patient group vs an exercised patient group may be useful.

Reversible renal failure in the primary antiphospholipid syndrome--a report of two cases

The primary antiphospholipid/anticardiolipin syndrome is a recently described entity wherein multiorgan thrombotic events occur in the absence of objective evidence of systemic lupus erythematosus. The spectrum of renal involvement remains poorly described. Two patients with coagulation abnormalities consistent with the primary antiphospholipid/anticardiolipin syndrome who developed profound renal insufficiency are reported. Striking microangiopathic lesions were documented on renal biopsy. Renal function improved concomitant to the institution of steroid therapy. Reversible renal failure should be added to the spectrum of clinical manifestations of this entity. The diagnosis of the primary antiphospholipid/anticardiolipin syndrome should be contemplated in individuals with unexplained acute renal failure.

Proximal femoral resection for older children with spastic hip disease

Thirteen patients (19 hips) who underwent proximal femoral resection arthroplasty for symptomatic subluxation or dislocation of the hip were reviewed retrospectively. All had severe neurological involvement, and when older were non-ambulatory with spastic quadriplegia or myelodysplasia. Resections were either at the level of the neck (nine hips) or in the subtrochanteric region (10 hips). The latter provided a better operative result than did the former. Poor clinical results noted were continued pre-operative pelvic obliquity, postoperative adduction contracture, and bony contact between the pelvis and the remaining proximal femur or its heterotopic ossification.

Femoral version and neck shaft angle

We measured femoral anteversion by the Kingsley-Olmsted method in 24 unpaired, dry femurs. When the head and neck of the same femurs were measured by computed tomography (CT) scan, measurement was 5 degrees less than the Kingsley-Olmsted method, whereas ultrasound of the head and neck was 5 degrees higher. An anterior flat plane was also defined to help measure anteversion in patients with a high neck shaft angle. Physical and ultrasound measurement correlated well with the previous measurement by the Kingsley-Olmsted method and CT scan of anteversion. Although measurement by CT scan and ultrasound are different their results are both reproducible and measure the same parameters; however, ultrasound measurement yields a number approximately 10 degrees higher.

A 5' splice junction mutation leading to exon deletion in an Ashkenazic Jewish family with phosphofructokinase deficiency (Tarui disease)

A deficiency of the muscle isoform of the enzyme, phosphofructokinase (PFK, EC 2.7.1.11), leads to an illness (glycogenosis, Type VII) characterized by myopathy and hemolysis. A patient with this disease and an affected sister were found to have a G to A substitution at the 5' donor site of intron 5 of the PFK-M gene. This mutation led to a splicing defect: a complete deletion of the preceding exon in the patient's mRNA. The patient, an affected sister, and related and unrelated family members, who were of Ashkenazic Jewish background, were screened for the mutation by denaturing gradient gel electrophoresis and by allele specific hybridization of genomic DNA. The affected sisters are homozygous for the mutation, and their children, who are unaffected, are heterozygous. The only previously characterized genetic defect in this disease, found in a Japanese patient, was a G to T mutation at the beginning of intron 15 with splicing to a cryptic site within exon 15 (1). Both mutations lead to inframe deletions, but of different parts of the protein. The differences between the two aberrant proteins may account for clinical differences between our patients and the Japanese patient.

Biliary cystadenocarcinoma arising in a liver with fibropolycystic disease

Intrahepatic cholangiocarcinoma associated with fibropolycystic disease of the liver and biliary cystadenocarcinoma are rare tumors that are considered distinct entities. We present a case of a malignant tumor with features of hepatic cystadenocarcinoma arising in a background of fibropolycystic disease.

Long-term follow-up of hip subluxation in cerebral palsy patients

Spastic subluxation of 64 hips in 45 patients with cerebral palsy (CP) was reviewed in a 19-year follow-up. Varus osteotomy prevented dislocation in all patients. All nine hips that later dislocated were in quadriplegic patients who had not received treatment or who had had muscle releases. Dislocated hips had the most degenerative arthritis, pain, and the least movement. Subluxated hips also had more degenerative arthritis but approximately the same level of pain as reduced hips.

Proximal femoral osteotomy using the AO fixed-angle blade plate

We describe the technique and results of proximal femoral osteotomy performed with the AO fixed-angle blade plate in 157 hips of 101 pediatric patients. Postoperative immobilization or restriction of activity was not prescribed. Fourteen complications occurred in 11 patients. Use of preoperative antibiotics decreased the rate of infection from 12% to 0%, which was significant. All osteotomies healed by 16 weeks postoperatively with no nonunions, malunions, device failures, or avascular necrosis. Using no postoperative immobilization in these children was successful and resulted in few complications when the appropriate-sized blade plate was used.

Evaluation of maternal fluid dynamics during tocolytic therapy with ritodrine hydrochloride and magnesium sulfate

OBJECTIVE

The purpose of the study was to observe and compare the effects of ritodrine hydrochloride and magnesium sulfate on maternal fluid dynamics.

STUDY DESIGN

Fourteen women in preterm labor were prospectively studied during tocolytic therapy with either ritodrine hydrochloride or magnesium sulfate. The cardiovascular and renal effects of a pretreatment crystalloid infusion were compared with those observed during tocolytic therapy. Profile analysis and repeated measures of variance were used to analyze the data.

RESULTS

Ritodrine hydrochloride was associated with decreased colloid osmotic pressure, hematocrit, and serum proteins and increased maternal and fetal heart rates. Arginine vasopressin levels increased during the first 2 hours of therapy, then returned to baseline. Sodium excretion was reduced and there was marked fluid retention. Intravenous magnesium sulfate also resulted in a reduction of colloid osmotic pressure, but hematocrit, serum protein concentration, arginine vasopressin, maternal and fetal heart rates, and mean arterial pressure were minimally affected. Sodium excretion increased to a maximum at 6 to 8 hours of treatment, then returned to baseline. A positive fluid balance was also noted in magnesium sulfate-treated patients but to a lesser degree than with ritodrine.

CONCLUSIONS

Sodium retention appears to be the primary cause of plasma volume expansion in ritodrine-treated patients, whereas volume expansion during magnesium sulfate therapy is probably related to intravenous overhydration. In the absence of risk factors for pulmonary capillary membrane injury, available evidence supports volume overload as the principal mechanism for pulmonary edema during tocolytic therapy.

Spinal fusion in Duchenne muscular dystrophy

Sixty-eight patients from a clinical population of 183 patients with Duchenne muscular dystrophy underwent posterior spinal fusion with instrumentation for progressive spinal deformity. Pulmonary complications were the most common postoperative problem, occurring in 17 per cent of the patients. A 35 per cent normal forced vital capacity was a reliable indicator of pulmonary complication risk. The patients with surgically stabilized spines were more comfortable in the later years of life and easier to care for, but deteriorating pulmonary function was not affected by the spinal fusion. The average age at death for the 29 boys who underwent spinal fusion was 18.3 years, which was similar to that of the 58 boys with scoliosis. Factors that improved the patients' quality of life included segmental instrumentation, fusion from T2 to the pelvis, correcting or balancing scoliosis, creating normal sagittal plane alignment and correcting pelvic obliquity.