Handling 'carbon footprint' in orthopaedics

INTRODUCTION

The National Health Service contributes 4%-5% of England and Wales' greenhouse gases and a quarter of all public sector waste. Between 20% and 33% of healthcare waste originates from a hospital's operating room, and up to 90% of waste is sent for costly and unneeded hazardous waste processing. The goal of this study was to quantify the amount and type of waste produced during a selection of common trauma and elective orthopaedic operations, and to calculate the carbon footprint of processing the waste.

METHODS

Waste generated for both elective and trauma procedures was separated primarily into clean and contaminated, paper or plastic, and then weighed. The annual carbon footprint for each operation at each site was subsequently calculated.

RESULTS

Elective procedures can generate up to 16.5kg of plastic waste per procedure. Practices such as double-draping the patient contribute to increasing the quantity of waste. Over the procedures analysed, the mean total plastic waste at the hospital sites varied from 6 to 12kg. One hospital site undertook a pilot of switching disposable gowns for reusable ones with a subsequent reduction of 66% in the carbon footprint and a cost saving of £13,483.89.

CONCLUSIONS

This study sheds new light on the environmental impact of waste produced during trauma and elective orthopaedic procedures. Mitigating the environmental impact of the operating room requires a collective drive for a culture change to sustainability and social responsibility. Each clinician can have an impact upon the carbon footprint of their operating theatre.

O102 We know about left gastric artery embolisation and will embio provide the next solution to treat obesity?

Introduction

Left gastric artery embolisation (LGAE) is a minimally invasive procedure which has shown promising results for weight loss in recent studies and could play a key role as a treatment option in-between our current tier-3 and tier-4 services. Imperial College NHS Trust will sponsor the EMBIO trial, the first multi-centre double blinded randomised controlled trial comparing LGAE vs Placebo procedure to evaluate its efficacy on weight loss and obesity related comorbidities over a 12 month follow up period. Here, we perform a systematic review of the existing literature.

Methods

9 studies were reviewed. Studies which investigated weight loss as a % +- Ghrelin % change at 3,6 and 12 months were included as these pre-defined time points correlate with the EMBIO protocol. 6 studies met our inclusion criteria, 5 single arm studies and 1 single blinded RCT.

Results

N=62 patients were included in our analysis. Mean weight loss reported was 8.5%, 8.8% and 10% at 3, 6 and 12 months respectively post LGAE. Ghrelin levels reduced by 36%, 16.2% and 16.5% at 3, 6 and 12 months respectively post LGAE. To date, the only reported adverse events recorded include superficial gastric erosions healed on endoscopy by day 90 and one case of subclinical pancreatitis.

Conclusion

LGAE potentially offers a day case procedure under local anaesthesia and sedation to treat obesity and its metabolic complications. The EMBIO trial will provide level 1 evidence to confirm if LGAE is a viable intervention for obesity and evaluate its safety profile.

Take-home message

Left gastric artery embolisation could be the perfect solution to treat obesity in between existing tier-3 and tier-4 treatments.

A snapshot of stroke from miri hospital

Our objective was to study the profile of cerebrovascular accidents and proportion of cerebral haemorrhage (CH) among stroke patients. This project was designed after we observed higher incidence of CH in Miri hospital as compared to conventionally reported data.

METHODS

This was a prospective observational study conducted from 1st June 2008 to 31st May 2009. All patients admitted in both male and female wards of the Medical Unit with the first incidence of a stroke were recruited for analysis. CT scan brain was done in all patients.

RESULTS

Total admissions in one year in the medical department were 3204 patients, both male and female together, out of which 215 were due to a first incidence of stroke; Stroke accounted for 6.7% of admissions and 16.8% of deaths in medical unit. 139 (64.7%) were ischaemic strokes and 76 (35.3%) were cerebral haemorrhages. The incidence of CH (35.3%) was high compared to regional data. 71.7% (154) patients had preexisting hypertension. Higher incidence of hypertension, diabetes mellitus and aspirin intake was noted in the ischaemic group. Also compliance to treatment for hypertension was better in the Ischaemic group with more defaults in CH category (P<0.01). Significantly more deaths were noted in patients with higher systolic blood pressure on presentation, poor Glasgow Coma Scale (GCS) and those with dysphagia.

CONCLUSION

Every third stroke was due to cerebral hemorrhage; CH patients were largely unaware of their hypertension or were altogether treatment naïve or defaulters while compliance was far better in ischaemic stroke category.

Fully automatic segmentation of the proximal femur using random forest regression voting

Extraction of bone contours from radiographs plays an important role in disease diagnosis, preoperative planning, and treatment analysis. We present a fully automatic method to accurately segment the proximal femur in anteroposterior pelvic radiographs. A number of candidate positions are produced by a global search with a detector. Each is then refined using a statistical shape model together with local detectors for each model point. Both global and local models use Random Forest regression to vote for the optimal positions, leading to robust and accurate results. The performance of the system is evaluated using a set of 839 images of mixed quality. We show that the local search significantly outperforms a range of alternative matching techniques, and that the fully automated system is able to achieve a mean point-to-curve error of less than 0.9 mm for 99% of all 839 images. To the best of our knowledge, this is the most accurate automatic method for segmenting the proximal femur in radiographs yet reported.

The pain of surgery: pain experienced by surgeons while operating

INTRODUCTION

The operating theatre can be a dreaded experience not only for the patient but also occasionally for the surgeon. We sought to investigate the prevalence of pain experienced by surgeons while operating.

METHODS

One hundred and thirty anonymous questionnaires were sent to surgical consultants in the Britain.

RESULTS

The response rate was 60% and 63 experienced pain while operating. The back and neck were the most common areas of pain (36 & 30 consultants respectively), followed by the hand (24 consultants). Nearly 80% described pains on a regular basis. Table height was the most common cause of pain (35%), followed by the use of microscopes (27%) and standing (22%). Nearly 43% of the consultants will take a break from surgery because of their symptoms, and 4 took sick leave in direct relation to pain experienced as a result of operating. However only 27% took measures to reduce their symptoms and 65% never sought any help or advice and only one consultant informed the occupational health department.

CONCLUSION

Many surgeons will experience pain while operating due to positioning or the instruments they use, however there are no guidelines from occupational health departments or training courses to help minimise these symptoms.

Choroid plexus cysts: Is biochemical testing a valuable adjunct to targeted ultrasonography?

OBJECTIVE

We sought to determine whether biochemical testing is a valuable adjunct to ultrasonography in selecting patients with fetal choroid plexus cysts for amniocentesis.

STUDY DESIGN

The study population consists of 128 patients who had fetal choroid plexus cysts detected during ultrasonography performed between 18 and 22 weeks' gestation. The patients had genetic counseling, and amniocentesis and biochemical testing were offered to all patients. The data were analyzed by dividing the patients into 3 groups. Group 1 had targeted ultrasonography only, group 2 had ultrasonography and maternal serum alpha-fetoprotein testing, and group 3 had ultrasonography and triple-screen (maternal serum alpha-fetoprotein, human chorionic gonadotropin, and estriol) testing. Outcome was determined by fetal karyotype or by neonatal examination by a pediatrician for patients who declined amniocentesis.

RESULTS

There were 25 patients in group 1. Isolated choroid plexus cysts were detected in 20 fetuses, and all had normal outcomes. Additional anomalies were detected in 5 fetuses. Two had normal karyotypes, and 3 had trisomy 18. There were 52 patients in group 2. The maternal serum alpha-fetoprotein levels were normal in 44 patients, 41 of whom had isolated fetal choroid plexus cysts. Of these 44 patients, 40 had normal outcomes, and 1 patient had a fetus with trisomy 18. The remaining 3 patients with normal maternal serum alpha-fetoprotein levels had additional fetal anomalies on ultrasonography, but the karyotypes were normal. The maternal serum alpha-fetoprotein levels were abnormal in 8 patients, of whom 6 had fetuses with isolated choroid plexus cysts and normal karyotypes. Two patients had additional fetal anomalies detected on ultrasonography and had abnormal karyotypes, 1 with trisomy 21 and 1 with trisomy 18. There were 51 patients in group 3. Results of the triple screen were normal in 32 patients. The choroid plexus cysts were isolated in 29 of the 32 patients, and all 29 fetuses had normal karyotypes. The other 3 patients with normal triple-screen results had additional fetal anomalies on ultrasonography. One fetus had normal chromosomes, and 2 had trisomy 18. The remaining 19 patients had abnormal triple-screen results. Among them, 16 fetuses had isolated choroid plexus cysts, 13 of whom were normal, 2 had trisomy 18, and 2 had a de novo unbalanced translocation. The remaining 3 fetuses had additional anomalies, and all 3 fetuses had trisomy 18. There were 14 fetuses with significant chromosomal abnormalities. Nine mothers were <35 years old, and 5 were >/=35 years old.

CONCLUSIONS

This study shows the following: (1) The triple screen is a useful adjunct to targeted ultrasonography in selecting patients with fetal choroid plexus cysts for amniocentesis. (2) A normal triple-screen result and the absence of additional fetal anomalies on ultrasonography reliably exclude an underlying chromosomal abnormality, and amniocentesis is not indicated. (3) If the triple-screen result is abnormal, additional anomalies are seen on ultrasonography, or the mother is aged >/=35 years, then fetal karyotyping is recommended. (4) Patients who decline fetal karyotyping should have follow-up ultrasonography in 34 weeks' time.

HELLP (hemolysis, elevated liver enzymes, and low platelet count) syndrome: the benefit of corticosteroids

OBJECTIVE

The purpose of this study was to determine the effect of corticosteroids on platelet counts and liver functions in women with pregnancies complicated by the HELLP (hemolysis, elevated liver enzymes, and low platelets) syndrome.

STUDY DESIGN

The study group consisted of 93 patients between 24 and 34 weeks' gestation diagnosed with HELLP syndrome. All were given intramuscular injections of either betamethasone or dexamethasone. The 3 most common regimens used were 12 mg of intramuscular betamethasone administered twice 12 hours apart, 12 mg of intramuscular betamethasone administered twice 24 hours apart, and 6 mg of intramuscular dexamethasone administered 4 times 6 hours apart. Precorticosteroid and postcorticosteroid platelet counts and liver function test results were compared. The differences in improvement in hematologic abnormalities among the 3 corticosteroid regimens were also analyzed.

RESULTS

The hematologic abnormalities seen in the 93 patients with HELLP syndrome improved after the administration of corticosteroids. The platelet count increased by 23.3 x 10(3)/microL (P <.001). A statistically significant decrease was seen in liver enzyme levels. The alanine aminotransferase decreased by 31.6 IU/L, the aspartate aminotransferase decreased by 52.1 IU/L, and the alkaline phosphatase decreased by 7.6 IU/L. Of the 3 regimens used, 2 doses of 12 mg of intramuscular betamethasone given every 12 hours improved the liver function to the greatest degree.

CONCLUSIONS

This study demonstrates that corticosteroids produce a significant improvement in the hematologic abnormalities associated with HELLP syndrome. Two doses of betamethasone given 12 hours apart was the most effective corticosteroid regimen.

Reasons for intracranial hypertension and hemodynamic instability during acute elevations of intra-abdominal pressure: observations in a large animal model

In previous studies we reported that an acute elevation in intra-abdominal pressure (IAP) is responsible for the elevation in intracranial pressure (ICP) and mean blood pressure (MBP). Thus far, the reasons for the increased ICP during an acute elevation in IAP and the combined effects of increased IAP and ICP on hemodynamics have not been reported. Five large animals (swine) were studied. Each animal served as its own control. A subarachnoid screw was placed for ICP monitoring. The jugular vein, femoral vein, and femoral artery were cannulated. ICP, MBP, central venous pressure above (CVPA) and below (CVPB) the diaphragm, and PaC02 were monitored after a pneumoperitoneum with C02 was established at 5, 15, and 30 mm Hg of IAP. Cavography was performed to evaluate the morphology of the inferior vena cava at different increments of IAP. Measurements were obtained in reverse Trendelenburg (group 1), supine (group 2), and Trendelenburg (group 3) positions. Multiple regression analysis was used to examine the effects of IAP and positioning in separate models with different blood pressures as dependent variables. Increased IAP significantly increased CVPA, CVPB, ICP, and MBP. There were no changes in cerebral perfusion pressure. The change in position (from group 1 to group 3) significantly increased CVPA and decreased the CVPB. Cavograms performed on animals in the supine position with increased IAP showed a narrowing of the IVC at the level of the diaphragm. Increases in IAP will increase ICP and MBP without altering the cerebral perfusion pressure. A mechanical effect mediated by compression of the inferior vena cava at the level of the diaphragm with increased central venous pressure and decreased drainage from the lumbar plexus and central nervous system is responsible for this effect.

Elevated maternal serum alpha-fetoprotein levels: what is the risk of fetal aneuploidy?

OBJECTIVE

Our purpose was to present the findings of a project to determine the efficacy of including routine fetal karyotyping in the investigation of an elevated maternal serum alpha-fetoprotein concentration.

STUDY DESIGN

Targeted ultrasonographic examinations were performed in 658 patients with elevated maternal serum alpha-fetoprotein levels. The scans were normal in 557 women, of whom 427 consented to amniocentesis; 435 fetuses were karyotyped. In the 101 patients with abnormal ultrasonographic examinations 75 had fetal karyotyping.

RESULTS

In the 435 fetuses with normal scans, two had karyotypic anomalies, a 47,XYY and an inherited balanced translocation. Three fetuses with normal karyotypes and high amniotic fluid alpha-fetoprotein levels had congenital nephrosis. In the 101 patients with abnormal scans, 75 fetuses were karyotyped. There were four aneuploidies. Among the 26 patients with abnormal scans who declined amniocentesis one fetus with multiple anomalies was karyotyped after delivery and triploidy was discovered.

CONCLUSIONS

These results provide little justification for including fetal karyotyping in the investigation of elevated maternal serum alpha-fetoprotein when the targeted ultrasonographic examination is normal. When it is abnormal, selective rather than routine karyotyping is more appropriate.

Intraamniotic 15(s)-15-methyl prostaglandin F2 alpha and termination of middle and late second-trimester pregnancy for genetic indications: a contemporary approach

OBJECTIVE

Our purpose was to determine whether intraamniotic 15(s)-15-methyl prostaglandin F2 alpha could serve effectively and safely as a surrogate for natural prostaglandin F2 alpha when used to effect middle and late second-trimester pregnancy termination for genetic indications. Further, we sought to compare efficacy and side effects with those found when intravaginal prostaglandin E2 is used.

STUDY DESIGN

A total of 62 patients received intraamniotic 15(s)-15-methyl prostaglandin F2 alpha and urea, and intracervical laminaria. Case patients at < or = 20 weeks' gestation (n = 32) were compared with case patients at > 20 weeks (n = 30) and with a matched group (n = 64; 1:2 ratio) of control patients in whom cervical laminaria and intraamniotic urea were used with prostaglandin E2 vaginal suppositories.

RESULTS

The mean induction-to-abortion interval among the case patients (gestational age 16 to 27 weeks) was 13 hours 11 minutes; 60 of 62 (97%) were delivered within 24 hours. There was a statistically significant negative correlation between the induction-to-abortion interval and gestational age (p = 0.04). When patients at < or = 20 weeks and those at > 20 weeks were compared, few differences were noted. The mean induction-to-abortion interval for case patients at < or = 20 weeks was 13 hours 54 minutes versus 19 hours 34 minutes for control patients (p = 0.001). One of 32 (3%) case patients remained undelivered beyond 24 hours compared with 17 of 64 (27%) control patients (p < 0.01). Immediate and delayed complications were uncommon in either group.

CONCLUSION

Our study demonstrates that 15(s)-15-methyl prostaglandin F2 alpha can serve safely as a surrogate for prostaglandin F2 alpha when used in combination with urea and laminaria for termination of pregnancy. This technique appears safe for use through 27 weeks' gestation; further investigation is encouraged.

The Effects of Oxytocin on Intracranial Pressure

The commonly used vasodilators sodium nitroprusside and nitroglycerine increase the intracranial pressure (ICP). Oxytocin is also a vasodilator although its primary effect is contraction of uterine smooth muscle. We therefore studied the effect of oxytocin on the ICP of cats. Twelve cats were assigned to two equal groups. One group had normal ICP and in the other the ICP was artificially increased by inflating a balloon placed in the extradural space. All of the cats initially received an oxytocin infusion for 15 min. After a period of stabilization, an additional dose of oxytocin was injected as a bolus. Oxytocin administered as an infusion did not change the ICP significantly in any of the cats. Oxytocin administered as a bolus increased the ICP from 27 +/- 4 to 31 +/- 2 mm Hg in the cats with artificially increased ICP. There were no significant changes in the mean blood pressure or heart rate in either group.

Diagnosis and management of prenatally detected myelomeningocele: a preliminary report

Our experience with 23 cases of fetal myelomeningocele provides preliminary information on the outcome of these infants diagnosed in utero and managed by a multidisciplinary team. The mean age of diagnosis was 23.7 weeks (range, 16 to 34 weeks). Mean gestational age at delivery was 36.9 weeks in the 14 patients who elected to continue their pregnancies. None of the 11 infants with lumbosacral or sacral lesions developed significant ventriculomegaly before term. Of the three patients diagnosed with thoracolumbar lesions, two had progression of ventriculomegaly necessitating early delivery at 32 to 34 weeks of gestation. These preliminary findings suggest that a coordinated prenatal and neonatal approach appears to result in a favorable prognosis for infants with myelomeningocele, but that neonatal complications are common, requiring careful monitoring and aggressive management.

Early diagnosis of spina bifida: the value of cranial ultrasound markers

Ultrasonography plays an integral part in the prenatal diagnosis of neural tube defects. However, experienced sonographers with careful evaluation are successful in accurately diagnosing spina bifida only 80-90% of the time. This study was conducted to evaluate the accuracy and reliability of certain cranial ultrasound markers--the "lemon sign," cerebellar abnormalities, microcephaly, and ventriculomegaly--in facilitating the diagnosis of spina bifida in patients referred for prenatal diagnosis. Open spina bifida was diagnosed in 24 of 44 fetuses found to have neural tube defects. The lemon sign and cerebellar abnormalities were identified in all 16 fetuses in whom the diagnosis of spina bifida was made between 16-24 weeks' gestation. In four of these fetuses, the lemon sign and cerebellar abnormalities were noted 1-2 weeks before the spinal defect was identified. Microcephaly was present in 69% and ventriculomegaly in 63% of the cases. In the eight cases diagnosed after 24 weeks' gestation, the lemon sign was less reliable, being noted in only 25% of the fetuses. Ventriculomegaly increased in frequency to 75% and cerebellar abnormalities and microcephaly were present in all. Our findings indicate that these cranial ultrasound markers are extremely reliable for the early diagnosis of spina bifida; their identification should alert ultrasonographers at all skill levels to the possibility of open spina bifida.

Multicystic dysplastic kidney: natural history of prenatally detected cases

To delineate the natural history of fetal multicystic dysplastic kidneys (MDKs), all cases that were prenatally detected in the Prenatal Diagnosis Center of the University of Virginia from September 1985 to 31 August 1988 were reviewed. All patients were followed through the Center with serial ultrasound evaluations at approximately 4-week intervals, and each liveborn infant was evaluated and followed by one of the authors (S.S.H.). Of the 14 cases detected, ten were detected in the second trimester, the earliest at 16.5 weeks' gestation. Of the nine fetuses with non-lethal disease, there were two cases in which the lesion remained unchanged during observation. Both had an initial diagnosis in the third trimester. In those cases diagnosed in the second trimester (7), all showed an initial increase in the size and number of cysts, followed by involutional changes either in utero (2) or in the neonatal period (3). Two infants had immediate surgical removal of the MDK, one because of respiratory compromise, and the other because of an uncertain diagnosis on renal scan. Abnormalities of the contralateral kidney were found in 7 of 14 fetuses. Five were lethal conditions. Associated non-renal abnormalities were common in bilateral MDK (80 per cent), but rare in unilateral MDK (11 per cent).

The role of ultrasonography and amniocentesis in the evaluation of pregnancies at risk for neural tube defects

To assess the relative efficacy of amniocentesis versus targeted (detailed) ultrasonography, 225 patients referred because of an elevated maternal serum alpha-fetoprotein level (79.6%) or a family history of neural tube defect (20.4%) were evaluated. Ultrasonographic examination alone detected all 26 fetal abnormalities (11 cases of anencephaly, 10 cases of open spina bifida, and five other anomalies). Twenty-eight patients declined amniocentesis; all had normal pregnancy outcomes. Of the 167 patients with apparently normal fetal anatomy by sonography, seven had elevated alpha-fetoprotein levels but no acetylcholinesterase in the amniotic fluid. Six of these pregnancies resulted in normal infants; one infant had congenital nephrosis. The remaining 160 patients had normal sonograms with normal amniotic fluid alpha-fetoprotein levels and no fetal malformations at delivery. Although these results suggest that targeted ultrasonography by experienced personnel is a reasonable alternative to amniocentesis in evaluations for neural tube defects, the availability, cost-effectiveness, and diagnostic accuracy of this approach must be well documented in large prospective studies.

Venous sonography for pregnancy-related thrombosis: case report

Venous sonography offers a reliable, noninvasive way of diagnosing deep venous thrombosis in the lower extremity, a condition with a potentially fatal consequence. It is possible that sonography may underestimate the degree of involvement of the veins. However this is not usually of clinical concern since systemic heparin therapy will be given regardless of the extent of the clot.

Early versus late tocolytic treatment for preterm premature membrane rupture

The effect of tocolytic therapy before labor was evaluated in 33 pregnant women with preterm premature rupture of the membranes. Either intravenous magnesium sulfate or oral terbutaline was administered at the time of presentation. Intensive surveillance to detect signs of infection was carried out for all patients. In 29 of the patients in this treatment group who were seen at less than 34 weeks, a significantly longer prolongation of pregnancy was achieved when compared with 24 similar women treated after onset of labor in the hospital (169 hours versus 77 hours, p = 0.05). Duration of infant hospitalization was less for those mothers receiving tocolytic agents before labor. Maternal and infant infection were not different in the two groups; nor was the cesarean section rate. When this treatment group was compared with another control group of 96 women already in labor at presentation, the difference in time from admission to delivery was substantial, but it did not achieve statistical significance. In this group the rate of maternal infection was significantly higher, but newborn morbidity was not. Aggressive early treatment with tocolytic agents in pregnant women with preterm premature membrane rupture is more productive but not more dangerous than conservative management.

Effect of suxamethonium on the ICP of cats with and without thiopentone pretreatment

Twelve cats were assigned equally to two groups, one with normal, and the other with artificially-increased intracranial pressure. When suxamethonium was administered to these animals, the intracranial pressure increased in both groups, irrespective of their baseline intracranial pressure. When the same dose of suxamethonium was administered after pretreatment with thiopentone in both groups of animals, the intracranial pressure again increased from the control values.

Fetal evaluation by percutaneous blood sampling

Percutaneous umbilical blood sampling (cordocentesis) provides direct access to the fetal circulation in the second and third trimesters of pregnancy. Seventeen patients underwent this procedure between December 1985 and December 1986 for evaluation of a variety of clinical situations, including nonlethal fetal abnormalities detected by ultrasound, equivocal results of amniocentesis, nonimmune fetal hydrops, and isoimmune disorders. Our experience confirms the efficacy of the procedure and suggests that it may become an important tool for fetal assessment and therapy.

Glycosylated serum protein level as a screening and diagnostic test for gestational diabetes mellitus

Glycosylated serum protein assay was examined as an alternative to standard glucose screening and glucose tolerance testing. In a comparison of two groups of gravid women having abnormal 1-hour 50 gm glucose screening tests, there was no difference in glycosylated protein level in the group with abnormal glucose tolerance test results (9.4% +/- 2.0%, mean +/- SD; n = 8) versus normal results (9.2% +/- 1.07%, mean +/- SD; n = 11). Furthermore, correlation of glycosylated serum protein level with glucose screening test results was poor (r = 0.185, p = 0.23, n = 17). Glycosylated serum protein assay is not useful in detecting mild metabolic aberrations associated with gestational diabetes.

Effect of diltiazem-induced hypotension on normal and increased intracranial pressure of cats

The commonly used vasodilators sodium nitroprusside and nitroglycerin increase intracranial pressure (ICP) and cause tachycardia. Since diltiazem is also a vasodilator, we designed this experiment in cats to study its effect on intracranial pressure and heart rate (HR). Twelve cats were assigned to two equal groups. One group had normal ICP (N-ICP), while in the other the ICP was raised artificially (AR-ICP) by placing a balloon into the intracranial extradural space. Both groups received an infusion of diltiazem to decrease the mean blood pressure (BP), which was maintained 30 per cent below the baseline value for 15 minutes. Diltiazem caused no significant change in ICP (5.7 +/- 1 to 6.7 +/- 1.5 mmHg, p less than 0.01) in cats with N-ICP while in cats with AR-ICP, the increase from 26.9 +/- 0.5 to 34.0 +/- 1.9 mmHg was significant (p less than 0.006). HR decreased significantly during the diltiazem infusion in both groups.

Profound hypotension complicating magnesium therapy

Two preeclamptic women became profoundly hypotensive while receiving magnesium sulfate. No evidence of toxic levels was present in either. In both, preeclampsia-induced hypovolemia was extreme. That nontoxic magnesium levels can cause severe hypotension is an alarming possibility. Acknowledgment of this complication and expeditious reversal of the problem is essential.

Magnesium sulfate and ritodrine hydrochloride: systemic and uterine hemodynamic effects

Effects of magnesium sulfate and ritodrine hydrochloride on cardiovascular physiologic characteristics were studied in 70 human subjects treated for preterm labor. Systemic and uterine hemodynamic effects were investigated in five pregnant rhesus monkeys. Systolic blood pressure was minimally affected by either agent. Diastolic pressure, while not affected by magnesium sulfate, decreased 26.3% during ritodrine therapy. Maternal and fetal heart rates were minimally affected by magnesium sulfate. Ritodrine increased maternal and fetal heart rates significantly. In the monkeys, magnesium sulfate increased uterine and placental blood flows (by the microsphere technique) but failed to alter cardiac output. Ritodrine produced an increase in cardiac output but decreased perfusion pressure. Placental blood flow decreased by an average of 27.6%. Ritodrine would therefore seem contraindicated with a compromised fetal environment. Magnesium sulfate, by not altering perfusion pressure, may have a beneficial effect on uterine hemodynamics. These specific and distinct differences in cardiovascular and hemodynamic effects should be considered when either magnesium sulfate or ritodrine is selected as a tocolytic agent.

Antibiotic irrigation prophylaxis in the high-risk cesarean section patient

Two hundred twenty-three women who underwent cesarean section delivery were studied to assess the effectiveness of operative antibiotic irrigation in preventing postoperative uterine infection. Patients were prospectively randomized into high-risk and low-risk groups according to length of labor, and received irrigation with either a 2 gm solution of cefamandole or normal saline solution, or no irrigation. Infection rates of 48.6% and 54.8% were observed in high-risk patients given either saline solution or no irrigation, respectively. Three of 27 high-risk patients (11.1%) given antibiotic irrigation developed metritis. The authors find this method of preventing infection to be advantageous in terms of both efficacy and minimization of antibiotic exposure.

The significance of fetal heart rate decelerations during nonstress testing

Over a 9-month time span, eight gravid women at high risk had fetal heart rate decelerations on nonstress tests (NSTs). This form of antepartum evaluation, the standard at our institution, was performed 918 times on 476 women during this period. Decelerations were required to be between 1 and 10 minutes in duration and less than 90 bpm, or greater than 40 bpm below baseline, for inclusion. Of the eight women (1.7% of the total tested), four had reactive and four nonreactive NSTs. All eight had contraction stress tests (CSTs) that were negative by definition. Of four women allowed to labor, two (50%) required cesarean section for fetal distress. Two instances of fetal death (25%) occurred during observation periods of 36 and 48 hours. Two infants were growth retarded, and two had abnormal cord positions. NSTs showing decelerations of this type, regardless of reactivity or of follow-up CST, are abnormal and should be viewed with alarm. In term pregnancy, such fetuses should be delivered. In preterm pregnancy with nonreactive NSTs, decelerations may also be valid grounds for delivery. Some discrimination is possible in preterm pregnancies when the NST is reactive.

Thrombocytopenia in preeclampsia: associated abnormalities and management principles

Severe thrombocytopenia, abnormal liver function, and renal dysfunction may occur as manifestations of preeclampsia. Failure to recognize that this cluster of abnormalities represents a form of preeclampsia may result in erroneous initial diagnoses. Management of 13 such patients has shown a direct correlation between the degree of thrombocytopenia and the measures of liver dysfunction. Platelet counts and liver functions improved prior to delivery in five patients treated with corticosteroids. Management should be directed toward investigation and correction of deranged physiology and appropriate monitoring of maternal-feto-placental status. Early delivery is indicated in patients with progressive thrombocytopenia and in those with evidence of fetal maturity or distress. Provided that the disease process remains stable, consideration should be given in cases of fetal immaturity, to the use of betamethasone therapy. The occurrence of severe thrombocytopenia in 20% of neonates should be a consideration in selecting the mode of delivery.

Prolactin secretion by human chorion-decidua in vitro: influences of mode of delivery and agents that modify prostaglandin synthesis

Prolactin production by human decidua was examined with the use of a short-term tissue explant system. Decidua obtained after normal spontaneous vaginal deliveries produced significantly more prolactin than did tissue obtained after elective repeat cesarean section deliveries in the absence of labor (P less than 0.005). Cytosolic prolactin levels did not differ between the two delivery modes. Oxytocin (4.3 X 10(-11) M to 4.3 X 10(-6) M) and eicosatetraenoic acid (10(-7) M to 10(-4) M) had no effect on prolactin production or storage by decidual tissue. Indomethacin at 10(-4) M reduced only levels of stored prolactin but had no effect on stored or produced prolactin at lower concentrations (10(-7) M to 10(-5) M). Arachidonic acid (10(-4) M) suppressed both production and storage of prolactin (P less than 0.05). Decidual tissue from the two delivery modes did not differ in response to the above agents. Although the exact mechanism(s) remains obscure, these results indicate decidual prolactin production is altered by some aspect of labor. The possible involvement of prostaglandin precursors in mediating this production cannot be excluded.

Anaesthetic considerations in patients with mitral valve prolapse

Mitral valve prolapse (MVP), reported as occurring in up to 17% of healthy individuals, is considered to be the commonest cardiac valvular abnormality. Although the anaesthetic course may be uneventful, complications may arise for the first time in the peri-operative period and include life threatening dysrhythmias, mitral regurgitation and infective endocarditis. Anaesthetic management of three of the seven patients with MVP treated at our institution over a 12-month period is discussed and the literature reviewed.

The use of magnesium sulfate as the primary tocolytic agent to prevent premature delivery

The efficacy of magnesium sulfate was evaluated as the primary tocolytic agent in the management of patients at risk for premature delivery. One hundred ninety-two patients determined to be 36 weeks' gestation or less were treated. One hundred seven patients (55.7%) received an additional oral beta-mimetic agent once labor was arrested. One hundred nineteen patients had intact membranes and 73 patients had ruptured membranes. Delay of delivery of 48 hours or longer was achieved in 70.6% of the patients with intact membranes and 60.2% of patients with ruptured membranes. Intervening obstetric complications, maternal morbidity, and neonatal septic and respiratory morbidity were increased in patients with ruptured membranes compared to patients with intact membranes. Magnesium sulfate is considered to be effective tocolytic agent having minimal adverse effects in managing patients at risk for premature delivery. Its use in patients with ruptured membranes, as with any tocolytic agent, remains controversial.

Disseminated intravascular coagulation in pregnancy. The role of heparin therapy

Treatment of the underlying cause and supportive care constitute the basic principles of management of disseminated intravascular coagulation. The role of anticoagulation with heparin is controversial in the absence of any controlled studies. This case report describes two patients with acute obstetric disseminated intravascular coagulation in whom the use of heparin resulted in marked clinical improvement. Treatment with heparin may be of help in situations where there is a delay in elimination of the underlying cause.

Torsion of the normal fallopian tube in pregnancy

Two cases of torsion of the normal fallopian tubes during the third trimester of pregnancy are presented. The etiology and clinical features of this complication are discussed. Although uncommon, it should be included in the differential diagnosis of abdominal pain in pregnancy.

Ectopic pregnancy: current clinical trends

During the 16 year period ending in November, 1978, 191 cases of ectopic pregnancy were managed at the University of Virginia Hospital. The overall incidence was 1/126 deliveries but during the last 3 years of the study the incidence was 1/60 deliveries. Only 56 patients have had a subsequent conception. Thirteen have had a recurrent ectopic implantation. Only 36 women (23.7% of those available for follow-up) have had subsequent term pregnancies. Ectopic pregnancy continues to be a major gynecologic problem and the potential for subsequent fertility is poor.