The discrepancy between maturation of visual-evoked potentials and cognitive outcome at five years in very preterm infants with and without hemodynamic signs of fetal brain-sparing

OBJECTIVE

After intrauterine growth restriction we found at the age of 6 months an acceleration of neurophysiologic maturation. However, at later ages impaired cognitive outcome has been reported. Therefore, we investigated in children with and without fetal hemodynamic adaptation to intrauterine growth restriction whether the accelerated neurophysiologic maturation in infancy might be associated with impaired cognitive outcome at preschool age.

DESIGN

At 5 years of age cognitive function was assessed using the Revision of the Amsterdam Children's Intelligence Test in 73 preterm infants (26-33 weeks) who were prospectively followed from the antenatal period up to the age of 5 years. Maternal educational level was used as a background variable to estimate the confounding effects of socioeconomic status on cognitive function. Fetal Doppler studies were performed and the umbilical artery pulsatility index (PI) divided by the middle cerebral artery PI ratio (U/C ratio) was calculated. A U/C ratio >0.725 was considered as an indication of fetal cerebral hemodynamic adaptation to a compromised placental perfusion, ie, fetal brain-sparing. Visual-evoked potentials (VEPs) were recorded at 6 months and 1 year of age. In addition, data on neurologic status at 3 years were available.

RESULTS

Mean IQ score was significantly lower for children born with a raised U/C ratio (87 +/- 16) compared with children with a normal U/C ratio (96 +/- 17). VEP latencies decreased significantly in infants with a normal U/C ratio, whereas no decrease was found in infants with a raised U/C ratio. Variables contributing significantly to the variance of cognitive function were: U/C group, VEP latency maturation, level of maternal education, and neurodevelopmental outcome at 3 years. The linear regression model explained 33% of the variance in cognitive function.

CONCLUSIONS

Both being born with a raised U/C ratio and an acceleration of VEP latencies are negatively associated with cognitive outcome at 5 years of age. Fetal brain-sparing, although a seemingly beneficial adaptive mechanism for intact neurologic survival, is, however, later associated with a poorer cognitive outcome.

Estimation of beat-to-beat changes in stroke volume from arterial pressure: a comparison of two pressure wave analysis techniques during head-up tilt testing in young, healthy men

OBJECTIVE

The aim of this study was to compare beat-to-beat changes in stroke volume (SV) estimated by two different pressure wave analysis techniques during orthostatic stress testing: pulse contour analysis and Modelflow, i.e., simulation of a three-element model of aortic input impedance.

METHODS

A reduction in SV was introduced in eight healthy young men (mean age, 25; range, 19-32 y) by a 30-minute head-up tilt maneuver. Intrabrachial and noninvasive finger pressure were monitored simultaneously. Beat-to-beat changes in SV were estimated from intrabrachial pressure by pulse contour analysis and Modelflow. In addition, the relative differences in Modelflow SV obtained from intrabrachial pressure and noninvasive finger pressure were assessed.

RESULTS

Beat-to-beat changes in Modelflow SV from intrabrachial pressure were comparable with pulse contour measures. The relative difference between the two methods amounted to 0.1+/-1% (mean +/- SEM) and was not dependent on the duration of tilt. The difference between Modelflow applied to intrabrachial pressure and finger pressure amounted to -2.7+/-1.3% (p = 0.04). This difference was not dependent on the duration of tilt or level of arterial pressure.

CONCLUSIONS

Based on different mathematical models of the human arterial system, pulse contour and Modelflow compute similar changes in SV from intrabrachial pressure during orthostatic stress testing in young healthy men. The magnitude of the difference in SV derived from intrabrachial and finger pressure may vary among subjects; Modelflow SV from noninvasive finger pressure tracks fast and brisk changes in SV derived from intrabrachial pressure.

In-hospital cardiopulmonary resuscitation: prearrest morbidity and outcome

BACKGROUND

Considerations about the application of cardiopulmonary resuscitation (CPR) should include the expected probability of survival. The survival probability after CPR may be more accurately estimated by the occurrence in time of the prearrest morbidity of patients.

OBJECTIVE

To identify risk factors for poor survival after CPR in relation to the dynamics of prearrest morbidity.

METHODS

Medical records of CPR patients were reviewed. Prearrest morbidity was established by categorizing the medical diagnoses according to 3 functional time frames: before hospital admission, on hospital admission, and during hospital admission. Indicators of poor survival after CPR were identified through a logistic regression model.

RESULTS

Included in the study were 553 CPR patients with a median age of 68 years (age range, 18-98 years); 21.7% survived to hospital discharge. Independent indicators of poor outcome were an age of 70 years or older (odds ratio [OR]=0.6, 95% confidence interval [CI]=0.4-0.9), stroke (OR=0.3, 95% CI=0.1-0.7) or renal failure (OR=0.3, 95% CI=0.1-0.8) before hospital admission, and congestive heart failure during hospital admission (OR=0.4, 95% CI=0.2-0.9). Indicators of good survival were angina pectoris before hospital admission (OR=2.1, 95% CI=1.3-.3.3) or ventricular dysrhythmia as the diagnosis on hospital admission (OR=11.0, 95% CI=4.1-33.7). Based on a logistic regression model, 17.4% of our CPR patients (n= 96) were identified as having a high risk for a poor outcome (< 10% survival).

CONCLUSIONS

Time of prearrest morbidity has a prognostic value for survival after CPR. Patients at risk for poor survival can be identified on or during hospital admission, but the reliability and validity of the model needs further research. Although decisions will not be made by the model, its information can be useful for physicians in discussions about patient prognoses and to make decisions about CPR with more confidence.

A negative iodine balance is found in healthy neonates compared with neonates with thyroid agenesis

We studied the effects of the presence or absence of the thyroid gland on the iodine metabolism and excretion in term Dutch newborns by performing a retrospective study of the urinary iodine excretion in 193 term newborns with abnormal congenital hypothyroidism screening results. Thirty-six euthyroid newborns with decreased thyroxine-binding globulin levels were compared with 157 hypothyroid patients, 54 due to thyroid agenesis and 103 due to thyroid dysgenesis. A significant difference in the urinary iodine excretion was observed between the agenesis group (mean: 28 micrograms/24 h) and the euthyroid newborns (mean: 46 micrograms/24 h, P=0.001). In conclusion, healthy, euthyroid, term newborns excreted more iodine in their urine than newborns with thyroid agenesis. These results strongly indicated the existence of a temporarily negative iodine balance: the excretion of iodine prevailed over the intake and the newborn's thyroidal iodine, stored during pregnancy, could be used for thyroxine synthesis in the postnatal period. Since healthy term neonates were able to maintain adequate plasma free thyroxine concentrations under normal TSH stimulation, the prenatally acquired iodine stores could be considered sufficiently high to compensate for the transient postnatal losses.

Thoracic duct in patients with multiple organ failure: no major route of bacterial translocation

OBJECTIVE

To determine whether translocation of bacteria or endotoxin occurred into the thoracic duct in patients with multiple organ failure (MOF).

SUMMARY BACKGROUND DATA

Translocation of bacteria or endotoxin has been proposed as a causative factor for MOF in patients without an infectious focus, although it has rarely been demonstrated in patients at risk for MOF. Most studies have investigated the hematogenic route of translocation, but it has been argued that lymphatic translocation of bacteria or endotoxin by the thoracic duct is the major route of translocation.

METHODS

The thoracic duct was drained for 5 days in patients with MOF caused either by generalized fecal peritonitis (n = 4) or by an event without clinical and microbiologic evidence of infection (n = 4). Patients without MOF who were undergoing a transthoracic esophageal resection served as controls. In lymph and blood, concentrations of endotoxin, proinflammatory cytokines, and antiinflammatory cytokines were measured.

RESULTS

Endotoxin concentrations in lymph and blood of patients with MOF ranged from 39 to 63 units per liter and were not significantly different from concentrations in patients without MOF. The quantity of endotoxin transported by the thoracic duct in the study group was small. In patients with MOF, low levels of proinflammatory cytokines and high levels of antagonists of these cytokines were found.

CONCLUSION

This study provides evidence that translocation (especially of endotoxin) occurs into the thoracic duct. However, these data do not support the concept that the thoracic duct is a major route of bacterial translocation in patients with MOF.

The prevalence of type 2 diabetes and gestational diabetes mellitus in an inner city multi-ethnic population

Zeeburg', a multiethnic town borough in the Amsterdam-East region, has one of the city's highest rates of immigrants. In the total population of 19,825 Surinam (mainly Creole), Turkish, Moroccan, and Dutch adults the prevalence of known type 2 diabetes in 1994 and of gestational diabetes mellitus (GDM) between January 1992 and January 1997 was investigated. Based on World Health Organization (WHO) criteria of 1985, the age-standardized prevalence of type 2 diabetes was similar in men (6.4%; 95% confidence interval [CI]: 5.6-7.2) and women (6.4%: 95% CI: 5.8-7.0) for all ethnic groups combined. However, the age- and sex-standardized prevalence of type 2 diabetes was significantly greater in the non-Dutch inhabitants than in the Dutch inhabitants (17.3% [95% CI: 12.9-21.6] in Surinam inhabitants, 10.9% [95% CI: 9.7-12.2] in Turkish inhabitants, 12.4% [95% CI: 9.7-15.0] in Moroccan inhabitants, and 3.6% [95% CI: 3.2-3.9] in Dutch inhabitants). The odds ratios for type 2 diabetes for the separate immigrant groups relative to the Dutch group were 5.88 (95% CI: 4.54-7.69) for Surinam inhabitants, 4.00 (95% CI: 2.86-5.55) for Turkish inhabitants, and 4.17 (95% CI: 3.03-5.55) for Moroccan inhabitants. GDM was present in 2.59% of women of non-Dutch origin compared with 0.62% of women of Dutch origin. A significant positive association was found between the non-Dutch origin and the occurrence of GDM (chi2 = 6.7; p < 0.01). The study highlights a high prevalence of known type 2 diabetes and GDM in the immigrant inhabitants and emphasizes that appropriate interventions are necessarily with implications for health targets and capitation based budgets.

Within-subject variability of differences between conventional and automated blood pressure measurements in pregnancy

OBJECTIVE

To determine whether measured differences between standard mercury sphygmomanometry and the SpaceLabs 90207 ambulatory blood pressure monitor in pregnant women remain constant during 24 h measurements.

STUDY DESIGN

Repeated comparisons between standard mercury sphygmomanometry and Spacelabs 90207 were performed at nine predetermined time points during 24 h ambulatory blood pressure measurements in a group of ten pregnant women with various pregnancy complications, including hypertension. Individual and group differences between standard mercury sphygmomanometry and SpaceLabs 90207 were calculated for each time point. Friedman's ANOVA was used to test stability of differences across time.

RESULTS

Mean group differences (standard deviation) between mercury sphygmomanometry and the SpaceLabs 90207 were -2 (6) mmHg and 3 (7) mmHg for systolic and diastolic pressure respectively. For systolic pressure the differences between time points were not statistically significant. Although a statistical significant trend was found for diastolic pressure differences (P<0.05), none of the contrasts between any pair of time points reached statistical significance. For both systolic and diastolic pressure the minimal and maximal difference lay at least 10 mmHg apart in seven patients.

CONCLUSIONS

Despite standardisation and training, a substantial within-subject variability of the pressure difference between observers and SpaceLabs was found in this heterogeneous group of women. However, a systematic time-related effect on this pressure difference could not be demonstrated. The pressure difference between both methods cannot be estimated with great precision. This is a serious impediment for the clinical interpretation of automated or ambulatory blood pressure data.

Neurodevelopmental outcome at three years of age after fetal 'brain-sparing'

Intrauterine growth restriction (IUGR), occurring preterm, may be related to impaired neurodevelopmental outcome. We measured neurodevelopmental outcome (Hempel examination) at the age of three years in a cohort of infants born between 26 and 33 weeks in 1989. Fetuses were studied haemodynamically, using Doppler ultrasound. The ratio between the umbilical and the cerebral artery Pulsatility Index (U/C ratio) was calculated. This is a measure of redistribution of fetal blood preferentially to the brain and this may be a marker of fetal adaptation to placental insufficiency. Impaired fetal growth was also measured by the fetal growth ratio. Neonatal cranial ultrasound was performed to document intracranial haemorrhages and/or ischaemia. From the original cohort of 106 infants, 96 (91%) infants were examined at three years. After adjustment for obstetric variables, adverse Hempel outcome was related to neonatal cranial ultrasound abnormality and low head circumference at three years. Neither the U/C ratio nor fetal growth were independently associated with Hempel outcome. Fetal 'brain-sparing' in IUGR appears to be a benign adaptive mechanism preventing severe brain damage.

Term and postterm twin gestations. Placental cause of perinatal mortality

OBJECTIVE

To compare perinatal mortality in twins and singletons and to study the influence of fetal sex, placentation and maternal parity on perinatal mortality in term and postterm twin gestations.

STUDY DESIGN

The subjects of the study were 1,511 twin pairs and 3,022 singletons. All were born at a gestational age of 27 weeks or more in two clinics in Amsterdam between 1931 and 1975.

RESULTS

Perinatal mortality was lower in twins than in singletons until 37-38 weeks and higher afterwards. In twins, perinatal mortality was higher in boys than in girls, in monochorial than in dichorial twins, and in primiparae than in multiparae, especially in the last trimester.

CONCLUSION

The development of the twin placenta may set limits in term and postterm twin gestations and may be responsible, to some extent, for the increase in perinatal mortality.

Fetal brain sparing is associated with accelerated shortening of visual evoked potential latencies during early infancy

OBJECTIVE

Our purpose was to assess the effects that fetal growth restriction exerts on the myelination of the developing brain.

STUDY DESIGN

Fetal haemodynamic centralization, an adaptive strategy to growth restriction caused by placental insufficiency, was determined by Doppler ultrasonography. Infants with a raised ratio between umbilical artery pulsatility index and cerebral artery pulsatility index are severely growth restricted. Visual evoked potentials give information on the degree of brain myelination. Shortening of visual evoked potential latencies is a normal feature of myelination. In a consecutive series of 105 Neonates, visual evoked potentials were recorded at the corrected ages of 6 months and 1 years. Correction for possible confounders, such as cranial ultrasonographic findings, gestational age, and head circumference, was performed.

RESULTS

At 6 months, infants with a raised umbilical artery/cerebral artery pulsatility index ratio have shorter visual evoked potential latencies. Opposite of neonates with a normal umbilical artery/cerebral artery ratio, they show no postnatal maturational shortening of visual evoked potential latencies.

CONCLUSION

Accelerated neurophysiologic maturation, found in infants with a high umbilical artery/cerebral artery ratio, might be the result of a beneficial adaptive process to severe fetal growth restriction.

The effect of long-term prednisone treatment on growth hormone and insulin-like growth factor-1

Due to a lack of longitudinal data the precise effect of long-term corticosteroid treatment on serum levels of the anabolic hormones Growth Hormone (GH) and Insulin-like Growth Factor-1 (IGF-1) is unknown. Therefore, we prospectively followed GH and IGF-1 levels over a six month period in 18 euthyroid patients with Graves' ophthalmopathy. Ten patients were treated with a three month course of prednisone; eight patients receiving retrobulbar irradiation served as controls. Baseline serum GH and IGF-1 levels were similar in both groups. Whereas no changes were seen in controls, prednisone induced a rapid increase in serum IGF-1 levels, which was sustained during the entire treatment period: 18.2 +/- 5.2 at baseline vs 24.1 +/- 6.7 nmol/l after 12 weeks of treatment (p < 0.001). After discontinuation of prednisone IGF-1 returned to baseline levels. Basal GH levels were frequently undetectable, but during treatment GH values were lower in the prednisone group (median of detectable values 4.0 mU/L [range 2.0-26.0]) than in controls (11.8 [2.8-44.0]; p < 0.01). In conclusion, long-term prednisone treatment is associated with suppressed GH levels and with an increase in total IGF-1 levels. This suggests that prednisone can disrupt the GH/IGF 1 axis.

Epidemiologic data on vulvar cancer: comparison of hospital with population-based data

Data on vulvar cancer are subject to a possible selection bias because older patients with vulvar cancer are sometimes not referred to specialized centers. The aim of this study was to compare the variables obtained from the population as a whole with variables obtained from referral and nonreferral hospitals. Population-based data on age, stage, histological type, and treatment modality were registered for 138 patients with vulvar cancer. The characteristics of the patients who were referred to a gynecologic oncology center were compared with those of the patients treated in nonreferral hospitals. The age-adjusted incidence was 2.3 per 100,000 women. Basal cell cancer was less common in the referral center than in the nonreferral centers (3% versus 28%). No difference was found in FIGO stage distribution in the different subgroups. Groin node dissection was omitted in 80% of the patients not referred to a center. Omission of groin node dissection was more common in patients older than 74 years (P = 0.002). Population-based data on vulvar cancer differ significantly from hospital-based data and give better insight into the real characteristics of patients with vulvar cancer.

Randomised controlled trial of single-dose antibiotic prophylaxis in surgical treatment of closed fractures: the Dutch Trauma Trial

BACKGROUND

The efficacy of prophylactic antibiotics in fracture surgery remains controversial for lack of well-documented prospective studies. We report here the findings of the Dutch Trauma Trial, a prospective, randomised, double-blind, placebo-controlled study of antibiotic prophylaxis in the primary operative treatment of limb fractures. Ceftriaxone was chosen because of its pharmacokinetic profile, including high serum levels, high tissue penetration, and long elimination half-life, makes it suitable for single-dose prophylaxis.

METHODS

Patients aged 18 years or more, attending one of fourteen Dutch centres for acute treatment of closed fractures, were randomly allocated to a single preoperative dose of ceftriaxone 2 g or placebo, and evaluated for development of wound infection and nosocomial infection at 10 days, 30 days, and 120 days. To assess the effects of drop-outs and withdrawals, best-case and worst-case analyses were performed.

FINDINGS

A total of 2195 patients were included. The incidence of superficial and deep wound infections after placebo was 8.3%, compared with 3.6% in the ceftriaxone group (p < 0.001, Pearson chi 2-test). The rate of nosocomial infection in the first month was 10.2% with placebo and 2.3% with ceftriaxone (p < 0.001, Pearson chi 2-test). Gram-positive bacteria were found in 74.5% of wound infections and 13.4% of nosocomial infections.

INTERPRETATION

Adequate single-dose prophylaxis with a long-acting broad-spectrum antibiotic substantially reduces the incidence of wound infection and early nosocomial infection after surgery for closed fractures.

The Amsterdam Preoperative Anxiety and Information Scale (APAIS)

The purpose of the present study was to assess patients' anxiety level and information requirement in the preoperative phase. During routine preoperative screening, 320 patients were asked to assess their anxiety and information requirement on a six-item questionnaire, the Amsterdam Preoperative Anxiety and Information Scale (APAIS). Two hundred patients also completed Spielberger's State-Trait Anxiety Inventory (STAI-State). Patients were able to complete the questionnaire in less than 2 min. On factor analysis, two factors emerged clearly: anxiety and the need for information. The anxiety scale correlated highly (0.74) with the STAI-State. It emerged that 32% of the patients could be considered as "anxiety cases" and over 80% of patients have a positive attitude toward receiving information. Moreover, results demonstrated that 1) women were more anxious that men; 2) patients with a high information requirement also had a high level of anxiety; 3) patients who had never undergone an operation had a higher information requirement than those who had. The APAIS can provide anesthesiologists with a valid, reliable, and easily applicable instrument for assessing the level of patients' preoperative anxiety and the need for information.

Anorectal surgery in human immunodeficiency virus-infected patients. Clinical outcome in relation to immune status

PURPOSE

Anorectal disease is commonly found in human immunodeficiency virus (HIV)-infected patients. The aim of this study was to determine the spectrum of anorectal disease, its surgical treatment, clinical outcome, and its relation to immune status.

METHODS

Medical records of all HIV-infected patients with anorectal pathology that required surgical treatment from January 1984 to January 1994 were retrospectively reviewed. Patients were divided into five different groups: common anorectal pathology (hemorrhoids, polyps, Group A); condylomata acuminata (Group B); perianal sepsis (abscesses, fistulas, Group C); anorectal ulcers (Group D); malignancies (Group E).

RESULTS

Eighty-three patients needed 204 surgical consultations (13 percent conservative, 87 percent operative) for 170 anorectal diseases. Fifty-one patients had multiple anorectal pathology. Operative intervention resulted in adequate wound healing and symptom relief in 59 percent of patients, adequate wound healing without relief of symptoms in 24 percent of patients, and disturbed wound healing was related to type of anorectal disease (P < 0.001) and to preoperative CD4(+)-lymphocyte counts (P < 0.01). Disturbed wound healing and most insufficient immune status were encountered in Groups C, D, and E. Within these groups low CD4(+)-lymphocyte counts were a risk factor for disturbed wound healing (P = 0.004). Median postoperative survival was highest (4.7 years) in Group A, lowest (0.6 years) in Groups D and E, and related to type of anorectal disease (P = 0.0001).

CONCLUSIONS

The spectrum of anorectal disease is complex. Type of anorectal disease is strongly related to immune status, wound healing, and postoperative survival.

Leish-KIT, a stable direct agglutination test based on freeze-dried antigen for serodiagnosis of visceral leishmaniasis

In order to increase the application potential of the direct agglutination test (DAT) for the detection of anti-Leishmania antibodies in human serum samples, we developed an antigen based on stained and freeze-dried Leishmania donovani promastigotes. We describe here the evaluation of the performance of the DAT based on this freeze-dried antigen. It was shown that the freeze-dried antigen remains fully active, even after storage at 56 degrees C for 18 months. With a cutoff value of 1:1,600, the sensitivity of the DAT was shown to be 92% and the specificity of the test was 99.7%, which were comparable with the results found for the DAT based on liquid antigen. The major advantages of the freeze-dried antigen are that the production of a large batch of this antigen allows reproducible results in the DAT over a long period of time and that the freeze-dried antigen can be stored at ambient temperature, which, as was shown, makes the test a valuable diagnostic tool for use in the field.

Extracapsular growth of lymph node metastases in squamous cell carcinoma of the vulva. The impact on recurrence and survival

BACKGROUND

Patients with squamous cell carcinoma of the vulva who present with multiple positive groin lymph nodes have poor survival. Growth of cancer through the capsule of the groin lymph nodes recently has been identified as an important prognostic factor for survival in that patient group. The objective of this study was to determine the influence of several clinicopathologic parameters on the pattern of recurrence and survival.

METHODS

A review of 71 patients with squamous cell carcinoma of the vulva and positive lymph nodes was performed to assess the independent prognostic value of a number of variables for survival. Variables analyzed included tumor size, stage, number of positive lymph nodes, extracapsular growth of lymph node metastasis, the greatest dimension of tumor in the lymph nodes, the percentage of replacement of the lymph nodes by tumor, clinical lymph node status, and laterality of positive lymph nodes.

RESULTS

Using the Mantel-Cox test, extracapsular growth of lymph node metastases (P = 0.00), two or more positive lymph nodes (P = 0.02), and greater than 50% replacement of lymph nodes by tumor (P = 0.03) were predictors of poor survival. No difference was found between the groups with two positive lymph nodes and those with three or more. Extracapsular growth of lymph node metastases was the most significant independent predictor for survival. Distant metastases occurred in 7 of 15 patients (48%) who had a combination of extranodal spread, lymph node replacement greater than 50%, and three or more positive lymph nodes.

CONCLUSION

Extracapsular growth of lymph node metastases in the groin is the most important predictor for poor survival in patients with squamous cell carcinoma of the vulva. Because of the predominant distant failure pattern in a subgroup of patients who have a combination of extranodal spread, multiple positive lymph nodes, and lymph nodes replaced by tumor greater than 50%, a future study of the effectiveness of systemic therapy for vulvar cancer must include these patients.

Neonatal cerebral circulation in relation to neurosonography and neurological outcome: a pulsed Doppler study

In the pathogenesis of neonatal intracranial pathology and adverse neurologic outcome, severe instability of the neonatal cerebral circulation might play an important role. To examine this hypothesis the relationship was explored between intracranial pathology as detected by neurosonography during the first week of life, changes in cerebral blood flow velocity (CBFV) as measured by Doppler ultrasound in the same period and neurologic outcome, as measured by standardized tests during the first year of life. A group of 128 infants born after a pregnancy duration between 25 2/7 and 32 6/7 weeks was studied. In 40% of the infants, the time of occurrence of both types of intracranial pathology was within 1 hour after birth. No relation could be demonstrated between this occurrence and CBFV. Also after the appearance of intracranial pathology no specific changes in CBFV were seen. CBFV was associated with neurological outcome at term age. However, CBFV did not predict outcome of neurological examination at 6 and 12 months of corrected age. Intracranial hemorrhages were associated with abnormal neurological outcome at all assessments. Ischemic lesions were only associated with adverse outcome at 12 months of age.

Effect of fetal brainsparing on the early neonatal cerebral circulation

The effect of antenatal brainsparing on subsequent neonatal cerebral blood flow velocity (CBFV) was studied in very preterm infants. CBFV was determined, using a pulsed Doppler technique, both in the fetal and neonatal period. Neonatally, blood pressure and transcutaneous carbon dioxide tension (TcPCO2) was monitored simultaneously; daily cranial ultrasound examinations were performed. In infants with evidence of brainsparing a higher mean value of CBFV and a different pattern of changes of CBFV during the first week of life was demonstrated compared with infants with normal fetal cerebral haemodynamics. No differences were found in blood pressure and TcPCO2. The incidence of intracranial haemorrhages and of ischaemic echo-dense lesions was also the same for both groups. In a multivariate statistical model gestational age, antepartum brainsparing, and TcPCO2 all contributed significantly in explanation of variation in CBFV. It is speculated that a different setting of cerebral autoregulation related to differences in gestational age or to brainsparing might explain the difference in changes found in neonatal CBFV.

Intra-observer and inter-observer reliability of the pulsatility index calculated from pulsed Doppler flow velocity waveforms in three fetal vessels

OBJECTIVE

Study of the intra observer and inter observer reliability of the pulsatility index, calculated from pulsed Doppler recordings of three fetal vessels.

DESIGN

Flow velocity waveforms (FVW) were recorded from the umbilical artery, the fetal descending aorta and the fetal internal carotid artery. Intra-observer reliability was assessed in six fetuses; ten repeated measurements were performed by one observer. Inter-observer reliability was studied in 14 fetuses; two observers performed two repeated measurements in each fetus.

SETTING

A tertiary referral hospital.

SUBJECTS

High risk pregnancies with a gestational age ranging from 29 to 42 weeks.

MAIN OUTCOME MEASURES

Analysis of variance with repeated measurements and a graphical method were used for data analysis. Intra-observer repeatability was expressed as Intraclass Correlation Coefficient (IntraCC). Inter-observer agreement was expressed as Interclass Correlation Coefficient (InterCC).

RESULTS

IntraCC for umbilical artery, descending aorta and internal carotid artery were 0.91, 0.78, and 0.54, respectively. InterCC values for these vessels were 0.39, 0.45 and 0.34, respectively. No systematic differences between the two observers except for the fetal descending aorta, were apparent. IntraCC decreased remarkable when fetuses with absent end diastolic velocities were excluded from the analysis.

CONCLUSION

The pulsatility index (PI) used for fetal measurements has a poor reliability. This is of serious concern when clinical use of FVW measurements is considered as a diagnostic tool.

Platelet aggregation, disc haemorrhage and progressive loss of visual fields in glaucoma. A seven year follow-up study on glaucoma

Platelet aggregation in vitro, deterioration of visual field defects (VFD) and the prevalence of disc haemorrhages (DH) were assessed in 49 patients with primary open angle glaucoma (POAG) and compared with the findings for 67 individuals with suspected glaucoma (GS) in a seven-year follow-up study (range 5.8 to 8.2 years). The percentage patients with spontaneous platelet aggregation (SPA) was higher for POAG patients with visual field deterioration (60%) than both POAG patients without progressive loss of visual fields (12.5%; P less than 0.005) and those with suspected glaucoma (22.4%; P less than 0.005). The occurrence of DH was higher among POAG patients with progressive loss of visual field (28%) compared to the GS group (8.4%; P less than 0.025) and the group of patients consisting of POAG patients without deterioration of VFD and GS (9.9%; P less than 0.05). DH also occurred more often in patients with low tension glaucoma (41.6%) than in the remaining POAG patients (13.5%; P less than 0.05). No relation between the patients with SPA and the patients with DH was observed.

Fetal and neonatal cerebral circulation: a pulsed Doppler study

We studied the relation between the fetal cerebral circulation and changes in the cerebral circulation directly after birth. With a combined real time ultrasound/pulsed Doppler technique flow velocity waveforms from the fetal umbilical- and carotid-circulation were monitored. Pulsatility Index (PI) was computed and the ratio between Umbilical PI and Carotid PI was calculated. Flow velocity waveforms of the cerebral circulation before birth were related to anterior cerebral artery flow velocity waveforms recorded immediately after birth. The study shows that changes in flow velocity waveforms associated with the intra uterine brain-sparing effect are related to poor obstetrical outcome. Furthermore is shown that the brain-sparing effect in the fetal period is associated with higher PI values in the cerebrovascular circulation in the neonatal period. It is suggested that changes in these PI values, representing changes in cerebrovascular resistance, might be indicative of cerebral ischemia in the neonate.

Dynamic loading of surgical knots

Lately, many suture materials have been introduced. Their physical characteristics in combination with knots are not well known. In this study, seven knots (square--1=1, 2=1, 2=1-S and 1=1=1--and sliding--SxSxS, S=S parallel S and 1-S parallel S parallel S) made in seven suture materials (plain catgut, Dexon [polyglycolic acid)] Maxon [polyglyconate], PDS [polydiaxone], Vicryl [polyglactine 910], Mersilene [polyester fiber], Prolene [polypropylene] were tested dynamically to ascertain tensile strength. The knots were classified as "predominantly breaking" (PB) and "predominantly slipping" (PS). A new method for statistical analysis, the Kaplan-Meier survival estimate, was introduced. Square knots provided good mechanical results but did not prevent slippage completely. Most sliding knots were weak. The 1=1=1 knot was superior. PS knots (1=1, 2=1, SxSxS and S=S parallel S) were unsuitable for surgical practice in monofilament or coated multifilament suture materials. The classification PB and PS knots gave an easy impression of the knot holding capacities. Application of the Kaplan-Meier estimate resulted in a more realistic analysis than classical methods.

Umbilical cord: factors which influence the separation time

The separation time of the umbilical cord was studied in 98 healthy Indonesian newborns with the aim of determining the normal time of separation and to evaluate factors which may influence it. The authors looked for a relationship between cord separation and sex, birthweight, gestational age, parity of the mother and nutrition of the newborn. Mean separation time was 10.9 days (S.D. 3: range 5-23 days). None of the factors analysed had a statistically significant influence. Cord care consisted of triple dye; no umbilical infections were found.

Umbilical cord length and intra uterine wellbeing

The length of the umbilical cord was studied in 179 Indonesian newborns to determine the normal range of cord length and its influence on the occurrence of intrapartum complications such as meconium stained amniotic fluid, asphyxia and entanglement of the cord around the fetus. The authors also attempted to investigate whether unfavourable intra uterine conditions could influence cord length. Therefore a correlation between cord length, sex, gestational age, birthweight and head-circumference was sought. The mean length of the umbilical cord was 52.2 cm., with a S.D. of 10.2 cm, ranging from 31-100 cm. Male infants had significantly longer umbilical cords than females (p = 0.02). The risk of complications increased parallel with cord length.

An increase in plasma cholesterol independent of thyroid function during long-term amiodarone therapy. A dose-dependent relationship

OBJECTIVE

To determine whether long-term amiodarone treatment is associated with a rise in plasma cholesterol, and, if so, to analyze its relation with thyroid function.

DESIGN

Consecutive entry trial, including cardiac patients who initiated amiodarone medication but excluding those with abnormal thyroid function (defined as peak thyroid-stimulating hormone [TSH] response to thyrotropin-releasing hormone [TRH] less than 2.8 or greater than 22.0 mU/L) either before or during amiodarone treatment.

PATIENTS

Twenty-three patients who remained euthyroid were studied.

INTERVENTION

Oral administration of amiodarone (mean duration of treatment, 17 months; range, 6 to 30 months).

MEASUREMENTS

Fasting plasma lipids, thyroid hormones, and peak TSH to TRH values were recorded before and every 6 months during amiodarone treatment.

RESULTS

Plasma cholesterol gradually increased from 5.1 +/- 0.2 mmol/L before treatment to 6.9 +/- 0.8 mmol/L after 30 months of amiodarone medication (P less than 0.001); the peak TSH response to TRH did not change. When age- and sex-specific reference values were applied, 30% of the patients had cholesterol values above the 75th percentile before treatment; this number rose to 69% after 2 years of treatment. The rise in plasma cholesterol was associated with an equal increase in apoprotein B. Plasma cholesterol was not related to the daily dose of amiodarone or to plasma concentrations of amiodarone, desethylamiodarone, thyroxine (T4), triiodothyronine (T3), or reverse triiodothyronine (rT3). Linear regression analysis indicated a positive relation between plasma cholesterol and the cumulative dose of amiodarone (r = 0.25, P less than 0.05).

CONCLUSION

Long-term amiodarone treatment is associated with a dose-dependent increase in plasma cholesterol that is independent of thyroid function.

A longitudinal study of the relationship between placental and fetal growth as measured by ultrasonography

Placental volume and fetal weight were estimated by ultrasonographic measurement at regular intervals from 16 to 20 weeks' gestation in 18 patients. The individual data were fitted to a logistic function. The estimated parameters were used to compare different groups of patients. In seven normal cases placental and fetal growth followed a sigmoid or nearly linear pattern. In four of these cases a reduction of placental and fetal growth during the last 1 to 3 weeks was apparent. In 11 cases with an abnormal outcome of pregnancy (fetal death, fetal distress necessitating a cesarean section, or neonatal weight below the 10th percentile) placental growth retardation always preceded fetal complications or growth retardation by at least 3 weeks.

Second-trimester placental volume measurement by ultrasound: prediction of fetal outcome

A prospective study evaluated sonographic second-trimester placental volume measurements in the prediction of fetal outcome. A parallel section scan method was used. Abnormal fetal outcome could be predicted with a sensitivity and specificity of approximately 90%. Evidence is given that fetal growth retardation is preceded by abnormal placental development in the first half of pregnancy. To a large extent, fetal birth weight and outcome are results of placental development and the ability of the placenta to meet the growing needs of the fetus as determined by its intrinsic growth potential.

Placental volume measurement by ultrasonography: evaluation of the method

A method for placental volume measurement by parallel ultrasonographic section scans is presented. An interval of 2 cm between the scans proves most effective. During measurement the patient should lie in the lateral position to prevent caval vein compression. The precision of the method as estimated by the SE is between 10 and 50 ml. The volume measured reflects both placental cellular mass and placental circulating blood volume. Drainage of the latter after delivery causes a fairly large difference between antepartum placental volume and postpartum placental weight (volume/weight ratio 1:6).

Platelet aggregation and glaucoma

In this study platelet aggregation was determined in 79 patients with primary open angle glaucoma (POAG) and 81 patients suspected of having glaucoma (ocular hypertension). There is a positive association between high age and the presence of vascular diseases (p less than 0.01). An age dependent association between spontaneous platelet aggregation (SPA) and the presence of POAG was also observed (p less than 0.05). This indicates that the incidence of SPA in the elder group of patients with POAG is higher than in the elder glaucoma suspect group and in the group of younger patients. The association between vascular diseases and SPA and between vascular diseases and the presence of POAG were not significant at the 5% level. The incidence of SPA is not influenced by sex distribution, by the presence of diabetes, smoking or the use of timolol maleate topically.

Prediction of infarct size from serial CK determinations: evaluation by clinical studies and computer simulation

To assess reduction of infarct size by therapeutic intervention, a high predictive accuracy is mandatory. The CK release in the circulation (CKr) was studied in 12 consecutive patients after uncomplicated myocardial infarction, admitted within 5 h after onset of symptoms. Despite improvement of existing methods, such as a more frequent sampling, CK-MB determination instead of total CK determination and use of a gamma-exponential instead of a log-normal curve-fitting technique, the correlation between CKr predicted from measurements within 7 h after the start of CK rise and CKr calculated after completion of the CK curve remained poor. Computer simulations were done to investigate measurement errors as a cause of this failure. Normally distributed noise, with standard deviations ranging from 0.2% to 8.0% of peak CK-MB, was added to the first points of an ideal gamma-exponential CK-MB curve and predictions were made from these "noisy" points. A small noise already produced a great variation in prediction: 0.8% noise resulted in a deviation of predicted CKr from calculated CKr ranging from --20 to +6%. It is concluded that adequate prediction of infarct size from serial CK determinations in the first 7 h after onset of the CK rise must fail if the precision of the biochemical determination is not less than 0.4%.