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.

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%.

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.

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.

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.

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.

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).

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.

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.

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.

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 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.

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.

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.

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.

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.

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.