Integrated approaches to academic anaesthesia - the Cambridge experience.

There is mounting concern about the pressures experienced by University Departments of Anaesthesia, which, if lost, could threaten undergraduate peri-operative medicine teaching, development of critical appraisal skills among anaesthetists, and the future of coherent research programs. We have addressed these problems by establishing a foundation course in scientific methods and research techniques (the Cambridge SMART Course), complemented by competitive, fully funded, 12-month academic trainee attachments. Research conducted during academic attachments has been published and used to underpin substantive grant applications allowing work towards higher degrees. Following the attachment, a flexible scheme ensures safe reintroduction to clinical training. Research at consultant level is facilitated by encouraging applications for Clinician Scientist Fellowships, and by ensuring that the University Department champions, legitimises and validates the allocation of research time within the new consultant contract. We believe that these are important steps in safeguarding research and teaching in anaesthesia, critical care and peri-operative medicine.

Management of comatose head-injured patients: are we getting any better?

This re-survey of neurosurgical centres was conducted to determine whether the publication of management guidelines has resulted in changes in the intensive care management of severely head-injured patients (defined as Glasgow Coma Score < 9) in the UK and Ireland. Results were compared with data collected from a similar survey conducted 2 years earlier. Almost 75% of centres monitor intracranial pressure in the majority of patients and 80% now set a target cerebral perfusion pressure of > 70 mmHg. The use of prolonged hyperventilation (> 12 h) is declining and the target PaCO2 is now most commonly > 4 kPa. More centres maintain core temperature < 36.5 degrees C. Although wide variations in the management of severely head-injured patients still exist, we found evidence of practice changing to comply with published guidelines.

A retrospective analysis of the effect of antenatal steroid administration on the incidence of respiratory distress syndrome in preterm twin pregnancies.

Respiratory distress syndrome (RDS) is the major cause of morbidity and mortality in preterm twin deliveries. Therapy with corticosteroids has been shown to reduce the incidence of RDS in preterm singleton gestations but similar reductions in twin pregnancies have not been demonstrated. Maternal and neonatal medical records were reviewed from twins delivered between 24 to 34 weeks gestation over the period of January 1, 1990 to December 31, 1994. Twenty-one pairs of twins received optimal steroid treatment defined as the use of two 12 mg doses of betamethasone, with birth occurring between 24 hours and 7 days after the first dose. Sixty-three pairs received no treatment. The mean gestational age at delivery was 29.9 +/- 2.6 weeks. No decrease was seen in the incidence of RDS (optimal steroid 70.7% versus no treatment 68.0%, unadjusted odds ratio [OR] 1.14, 95% confidence interval [CI] 0.49 to 2.65). Multivariate logistic regression showed no statistical difference in the incidence of RDS in the optimal steroid compared to the no treatment group (adjusted OR 0.63, 95% CI 0.2 to 1.95). No statistical differences were noted in the incidence of mechanical ventilation (58.6% versus 55.4%, p = 0.83), median duration of intubation (5.0 versus 5.0 days, p = 0.47), the median maximum inspiratory pressure requirements (20.0 versus 22.0 mm Hg; p = 0.15) in the optimal treatment versus no treatment group, respectively. The current regimen of antenatal corticosteroids utilized in twin pregnancies does not reduce the incidence of RDS.

The predictive value of maternal serum testing for detection of fetal anemia in red blood cell alloimmunization.

OBJECTIVE: Current management protocols for pregnancies complicated by red blood cell alloimmunization use the maternal antibody titer to predict the need for invasive testing for detection of fetal anemia. We investigated the use of three maternal serum tests to assess their usefulness in predicting fetal disease: indirect Coombs' titer, Marsh score, and monocyte monolayer assay. STUDY DESIGN: Forty-seven serum samples from pregnant women with red blood cell antibodies associated with fetal anemia were analyzed at cordocentesis. Fetal blood was analyzed for hematocrit (corrected for gestational age) and antigen status. Fetal anemia was defined as a hematocrit value of < 2 SD from the mean value for gestational age. Fetuses were classified into three groups: Antigen positive with anemia (n = 19), antigen positive without anemia (n = 17), antigen negative (n = 11). Statistical methods included Kruskal-Wallis test, Newman-Keuls test, Spearman's rank correlation, and receiver-operator characteristic curves; p < 0.05 was considered significant. RESULTS: The median monocyte monolayer assay (phagocytosis, adherence, and association) did not differ among the three groups. Both maternal titers and Marsh scores were significantly higher in fetuses with anemia compared with the other two groups of fetuses (256 vs 64 vs 64, p < 0.001, and 86 vs 69 vs 64, p = 0.02, respectively). Both titer and Marsh score exhibited significant correlations with corrected fetal hematocrit (r = -0.70, p < 0.001; r = -0.63, p < 0.001, respectively). Comparison of the overall receiver-operator characteristic curves for titer and Marsh score revealed no statistical difference; however, a Marsh score of 57 was noted to have a superior specificity than a titer of 16 (p = 0.02). CONCLUSION: The maternal Marsh score can be performed in conjunction with standard indirect Coombs' titers to enhance the predictability of fetal anemia.

Orbital rhabdomyosarcoma metastatic to the placenta.

Cancer coexisting with pregnancy is well reported; however, maternal malignancies that are metastatic to the products of conception are rare. We report a case of orbital rhabdomyosarcoma that metastasized to the placenta.

Selective second-trimester termination of the anomalous fetus in twin pregnancies.

Selective termination of the affected fetus was performed during the second trimester in 17 pregnancies in which one twin was diagnosed to be anomalous. The affected twin had a chromosomal aneuploidy in 14 cases, neural tube defect in two cases, and an inborn error of metabolism in one case. With increasing operator skill and improvement in technique, a striking improvement occurred in pregnancy outcome in the last 11 patients as compared with the first six. In four of the first six cases, the entire pregnancy was lost. Among the last 11 patients, on the other hand, no pregnancy was lost. All 11 women delivered healthy, viable infants; eight delivered at term and three delivered between 31-35 weeks. Of the various techniques used, we found intracardiac injection of potassium chloride to be the most effective, but it should not be used in monochorionic twin gestations.

Ultrasound detection of Down syndrome: is it really possible?

Several ultrasonographic signs have been described in second-trimester fetuses at high risk for Down syndrome. We examined these parameters in twin pregnancies in which one fetus was affected with Down syndrome and the other was normal. Biparietal diameter to femur length ratio was concordant (either normal or abnormal) in eight of nine sets of twins. Actual femur length to expected femur length ratio was concordant in seven of nine sets of twins. Nuchal fold thickening (6 mm or more) correctly identified five out of nine affected fetuses and was not present in any of the normal fetuses. In conclusion, neither ratio was helpful in differentiating the fetus with Down syndrome from its normal cotwin. A thickened nuchal fold was the most informative parameter examined.

Congenital rickets associated with magnesium sulfate infusion for tocolysis.

The records of five neonates born to mothers treated with intravenously administered magnesium sulfate for tocolysis were retrospectively reviewed to assess the presence of radiographic, clinical, and biochemical abnormalities. Two infants had radiographic bony abnormalities; one had frank rachitic changes and dental enamel hypoplasia. One of these patients, as well as an additional infant, had transient hypocalcemia. We hypothesize that prolonged infusion of magnesium sulfate, especially when initiated during the second trimester, may lead to fetal parathyroid gland suppression with consequent abnormalities resembling rickets.

Efficacy and side effects of magnesium sulfate and ritodrine as tocolytic agents.

Ritodrine as the first-line drug in the treatment of established preterm labor has been supplanted in some centers by magnesium sulfate. To assess the relative efficacy and rates of side effects of these two agents, 120 patients were randomly assigned to receive one of these two drugs. Patients were included if they had intact membranes and met strict criteria for the definition of labor. In both groups excellent outcome was achieved, with 96.3% and 92.3% of patients receiving ritodrine and magnesium sulfate, respectively, obtaining a delay in delivery of greater than 48 hours. Side effects were comparable in both groups, although they tended to be more serious in the patients receiving ritodrine. In patients receiving both drugs together, the rate of side effects was 77% without a demonstrable benefit over a single agent. We conclude that ritodrine and magnesium sulfate are tocolytics of comparable efficacy and when used aggressively are highly successful in delaying delivery.

Choroid plexus cysts in the fetus: a benign anatomic variant or pathologic entity? Report of 41 cases and review of the literature.

During a 22-month period, 6288 women undergoing prenatal sonographic studies in the second and third trimesters were evaluated prospectively to determine the incidence of choroid plexus cysts in the fetus, to follow the natural course of these cysts in intrauterine life, and to determine the association of chromosomal and anatomic anomalies in these fetuses. We diagnosed choroid plexus cysts in 41 fetuses, an incidence of 0.65%. Unilateral and bilateral cysts were equally frequent, and in most cases diagnosed by 21 weeks' gestation. On follow-up scans, the cysts had completely disappeared by 23-24 weeks in 80% of the cases, and by 28 weeks in another 10%. Once resolved, the cysts did not recur, and a normal sonogram in the late second trimester predicted normal scans in late pregnancy and in the neonate. One fetus had a chromosomal abnormality (trisomy 18). Associated anatomic anomalies were detected in three fetuses, including the one with trisomy 18. We believe that in the great majority of cases, fetal choroid plexus cysts are benign transient variants of normal intracranial anatomy. It is, however, important to conduct a careful sonographic search for associated anomalies. Chromosomal studies are strongly recommended whenever associated anatomic abnormalities are detected and when the choroid plexus cysts are large, bilateral, and persistent beyond 20-22 weeks' gestation.

Intravascular monitoring and management of erythroblastosis fetalis.

Over a 27-month period 17 pregnancies in 16 patients with severe red blood cell isoimmunization were managed with intravascular transfusions performed in utero. Fourteen of these women were Rh negative and sensitized to D or to both D and C, and the remaining two patients were sensitized to the Kell antigen (K). In 12 of the 17 cases (71%) the first intravascular transfusion was performed at 26.5 weeks' gestation or earlier. Thirty-nine of 45 attempted transfusions (87%) were successfully performed. All were done percutaneously under ultrasonic guidance. Two procedures were partial exchanges, while the remainder were straight transfusions. Thirteen of the 17 fetuses (76%) were alive at birth and survived the neonatal period. Four fetuses died in utero at 25 to 26 weeks' gestation, all within 12 hours of an intravascular transfusion. When the 27 procedures attempted during the most recent 9 months of this series were compared with the 18 procedures attempted during the preceding 18 months, no appreciable differences in technical success or fetal outcome were evident. An analysis of this experience is presented, along with modifications in technique that have been implemented. Unresolved issues are discussed.

The nonpredictive value of fetal urinary electrolytes: preliminary report of outcomes and correlations with pathologic diagnosis.

Fetal urine was sampled 12 times in nine fetuses with sonographically diagnosed urinary tract obstruction to assess renal function. By previously proposed criteria, four fetuses were predicted to have poor renal function. Two of these fetuses were found to have renal dysplasia on autopsy after elective termination. The other two died in the neonatal period but only one of these had histologic evidence of renal dysplasia. Five fetuses were predicted to have good renal function. Three of these developed renal failure after birth, one was found to have renal dysplasia on autopsy after elective termination, and one is alive and well. We conclude that fetal urine electrolytes are not necessarily an accurate predictor of neonatal renal function.

Decreasing frequency of iatrogenic neonatal respiratory distress syndrome.

A retrospective study was undertaken to evaluate the obstetric events preceding delivery of infants who developed respiratory distress syndrome (RDS) at one New York City hospital between January 1970 and July 1973, and January 1980 and July 1983. Elective delivery without adequate documentation of fetal maturity occurred in 7 (11.1%) of 63 pregnancies resulting in RDS during 1970-1973 as compared to only 1 (1.4%) of 71 pregnancies resulting in RDS during 1980-1983 (P less than 0.05). This decline in "iatrogenic" RDS presumably reflects improved physician diligence in the prevention of unnecessary RDS, increased availability of ultrasound and fetal lung maturity studies, and advances in the application and interpretation of these diagnostic procedures.

Long-term use of magnesium sulfate as a tocolytic agent.

Two patients in premature labor were treated continuously for six and 13 weeks with intravenous magnesium sulfate (MgSO4) for tocolysis. In each case, conventional therapy with intravenous and oral ritodrine failed to abate uterine contractions, and attempts to taper the MgSO4 were unsuccessful. Both pregnancies proceeded uneventfully otherwise, with normal fetal growth. Long-term MgSO4 may be a safe and efficacious alternative for occasional patients not responding to other modes of therapy for the treatment of premature labor.