Deployment of the National Notifiable Diseases Surveillance System during the 2022-23 mpox outbreak in the United States-Opportunities and challenges with case notifications during public health emergencies

Timely case notifications following the introduction of an uncommon pathogen, such as mpox, are critical for understanding disease transmission and for developing and implementing effective mitigation strategies. When Massachusetts public health officials notified the Centers for Disease Control and Prevention (CDC) about a confirmed orthopoxvirus case on May 17, 2023, which was later confirmed as mpox at CDC, mpox was not a nationally notifiable disease. Because existing processes for new data collections through the National Notifiable Disease Surveillance System were not well suited for implementation during emergency responses at the time of the mpox outbreak, several interim notification approaches were established to capture case data. These interim approaches were successful in generating daily case counts, monitoring disease transmission, and identifying high-risk populations. However, the approaches also required several data collection approvals by the federal government and the Council for State and Territorial Epidemiologists, the use of four different case report forms, and the establishment of complex data management and validation processes involving data element mapping and record-level de-duplication steps. We summarize lessons learned from these interim approaches to inform and improve case notifications during future outbreaks. These lessons reinforce CDC's Data Modernization Initiative to work in close collaboration with state, territorial, and local public health departments to strengthen case-based surveillance prior to the next public health emergency.

Developing Sampling Weights for Statistical Analysis of Parent-Child Pair Data From the National Health Interview Survey

The National Health Interview Survey (NHIS), conducted by the National Center for Health Statistics since 1957, is the principal source of information on the health of the U.S. civilian noninstitutionalized population. NHIS selects one adult (Sample Adult) and, when applicable, one child (Sample Child) randomly within a family (through 2018) or a household (2019 and forward). Sampling weights for the separate analysis of data from Sample Adults and Sample Children are provided annually by the National Center for Health Statistics. A growing interest in analysis of parent-child pair data using NHIS has been observed, which necessitated the development of appropriate analytic weights. Objective This report explains how dyad weights were created such that data users can analyze NHIS data from both Sample Children and their mothers or fathers, respectively. Methods Using data from the 2019 NHIS, adult-child pair-level sampling weights were developed by combining each pair's conditional selection probability with their household-level sampling weight. The calculated pair weights were then adjusted for pair-level nonresponse, and large sampling weights were trimmed at the 99th percentile of the derived sampling weights. Examples of analyzing parent-child pair data by means of domain estimation methods (that is, statistical analysis for subpopulations or subgroups) are included in this report. Conclusions The National Center for Health Statistics has created dyad or pair weights that can be used for studies using parent-child pairs in NHIS. This method could potentially be adapted to other surveys with similar sampling design and statistical needs.

The CDC Domestic Mpox Response - United States, 2022-2023

Monkeypox (mpox) is a serious viral zoonosis endemic in west and central Africa. An unprecedented global outbreak was first detected in May 2022. CDC activated its emergency outbreak response on May 23, 2022, and the outbreak was declared a Public Health Emergency of International Concern on July 23, 2022, by the World Health Organization (WHO),* and a U.S. Public Health Emergency on August 4, 2022, by the U.S. Department of Health and Human Services.^† A U.S. government response was initiated, and CDC coordinated activities with the White House, the U.S. Department of Health and Human Services, and many other federal, state, and local partners. CDC quickly adapted surveillance systems, diagnostic tests, vaccines, therapeutics, grants, and communication systems originally developed for U.S. smallpox preparedness and other infectious diseases to fit the unique needs of the outbreak. In 1 year, more than 30,000 U.S. mpox cases were reported, more than 140,000 specimens were tested, >1.2 million doses of vaccine were administered, and more than 6,900 patients were treated with tecovirimat, an antiviral medication with activity against orthopoxviruses such as Variola virus and Monkeypox virus. Non-Hispanic Black (Black) and Hispanic or Latino (Hispanic) persons represented 33% and 31% of mpox cases, respectively; 87% of 42 fatal cases occurred in Black persons. Sexual contact among gay, bisexual, and other men who have sex with men (MSM) was rapidly identified as the primary risk for infection, resulting in profound changes in our scientific understanding of mpox clinical presentation, pathogenesis, and transmission dynamics. This report provides an overview of the first year of the response to the U.S. mpox outbreak by CDC, reviews lessons learned to improve response and future readiness, and previews continued mpox response and prevention activities as local viral transmission continues in multiple U.S. jurisdictions (Figure).

Measuring Disability: An Examination of Differences Between the Washington Group Short Set on Functioning and the American Community Survey Disability Questions

Objective-This report examines differences in survey reports of disability between two sets of disability questions, the Short Set on Functioning (WG-SS) developed by the Washington Group on Disability Statistics (WG) and a set of disability questions developed for the American Community Survey (ACS).

Item Development and Performance of Tobacco Product and Regulation Perception Items for the Health Information National Trends Survey

INTRODUCTION

Emerging tobacco products have become increasingly popular, and the US Food and Drug Administration extended its authority to all products meeting the definition of a tobacco product in 2016. These changes may lead to shifts in public perceptions about tobacco products and regulation, and national surveys are attempting to assess these perceptions at the population level. This article describes the item development and cognitive interviewing of the tobacco product and regulation perception items included in two tobacco-focused cycles of the Health Information National Trends Survey (HINTS-FDA), referred to as HINTS-FDA.

METHODS

Cognitive interviewing was used to investigate how respondents comprehended and responded to tobacco product and regulation perception items. Adult participants (n = 20) were selected purposively to oversample current tobacco users and were interviewed in two iterative rounds. Weighted descriptive statistics from the fielded HINTS-FDA surveys (N = 5474) were also calculated.

RESULTS

Items were generally interpreted as intended, and participants meaningfully discriminated between tobacco products when assessing addiction perceptions. Response selection issues involved inconsistent reporting among participants with little knowledge or ambivalent opinions about either government regulation or tobacco products and ingredients, which resolved when a "don't know" response option was included in the survey. The fielded survey found that a non-negligible proportion of the population do not have clear perceptions of emerging tobacco products or government regulation.

CONCLUSIONS

A "don't know" response option is helpful for items assessing many emerging tobacco products but presents several analytic challenges that should be carefully considered. Multiple items assessing specific tobacco product and regulation perception items are warranted in future surveys.

IMPLICATIONS

The findings from this study can serve as a foundation for future surveys that assess constructs related to emerging tobacco products, harm perceptions across multiple tobacco products, and tobacco-related government regulatory activities. The data provide unique insight into item-specific motivation for selecting a "don't know" response option for tobacco survey items.

A Nonresponse Bias Analysis of the Health Information National Trends Survey (HINTS)

We conducted a nonresponse bias analysis of the Health Information National Trends Survey (HINTS) 4, Cycles 1 and 3, collected in 2011 and 2013, respectively, using three analysis methods: comparison of response rates for subgroups, comparison of estimates with weighting adjustments and external benchmarks, and level-of-effort analysis. Areas with higher concentrations of low socioeconomic status, higher concentrations of young households, and higher concentrations of minority and Hispanic populations had lower response rates. Estimates of health information seeking behavior were higher in HINTS compared to the National Health Interview Survey (NHIS). The HINTS estimate of doctors always explaining things in a way that the patient understands was not significantly different from the same estimate from the Medical Expenditure Panel Survey (MEPS); however, the HINTS estimate of health professionals always spending enough time with the patient was significantly lower than the same estimate from MEPS. A level-of-effort analysis found that those who respond later in the survey field period were less likely to have looked for information about health in the past 12 months, but found only small differences between early and late respondents for the majority of estimates examined. There is some evidence that estimates from HINTS could be biased toward finding higher levels of health information seeking.

Role of self-concept in answering survey questions on complementary and alternative medicine: challenges to and strategies for improving data quality

OBJECTIVES

The aim of this study was to assess the construct validity of survey questions about the use of herbal and other nonvitamin/nonmineral dietary supplements.

DESIGN

We conducted one-on-one, in-depth cognitive interviews with 32 respondents to test questions from the complementary and alternative medicine (CAM) supplement for the 2007 National Health Interview Survey. Respondents were sampled purposively according to their use of CAM. Interviewers probed respondents for their understanding of the questions, and analysis was guided by grounded theory, an approach that generates explanations of response error that are closely tied to the empirical data.

RESULTS

We found two sources of misinterpretation of CAM questions. First, some respondents did not have any pre-established definition of what constitutes an herbal supplement while others had interpretations that did not match the intended definitions. These problems are common to many survey questions. However, a second finding is that misinterpretation also arose when respondents incorporated notions of self-concept into the act of taking "natural herbs," and answered based on their understanding of this image rather than on actual behavior.

CONCLUSIONS

There are several sources of misinterpretation of CAM questions. One of the most important sources is whether or not the respondent has created a concept of self-image that includes the use of herbal supplements. Common questionnaire design techniques such as providing definitions to respondents will not help to eliminate misinterpretation due to self-image. We found that careful question wording that does not evoke definitions of self, combined with visual aids that narrow the focus of the questions, can lead to more accurate answers.

Is ischemia involved in the pathogenesis of murine cerebral malaria?

Sequestration of parasitized erythrocytes in the central nervous system microcirculation and increased cerebrospinal fluid lactate are prominent features of cerebral malaria (CM), suggesting that sequestration causes mechanical obstruction and ischemia. To examine the potential role of ischemia in the pathogenesis of CM, Plasmodium berghei ANKA (PbA) infection in CBA mice was compared to infection with P. berghei K173 (PbK) which does not cause CM (the non-CM model, NCM). Cerebral metabolite pools were measured by (1)H nuclear magnetic resonance spectroscopy during PbA and PbK infections. Lactate and alanine concentrations increased significantly at the terminal stage of CM, but not in NCM mice at any stage. These changes did not correlate with parasitemia. Brain NAD/NADH ratio was unchanged in CM and NCM mice at any time studied, but the total NAD pool size decreased significantly in the CM mice on day 7 after inoculation. Brain levels of glutamine and several essential amino acids were increased significantly in CM mice. There was a significant linear correlation between the time elapsed after infection and small, progressive decreases in the cell density/cell viability markers glycerophosphocholine and N-acetylaspartate in CM, indicative of gradual loss of cell viability. The metabolite changes followed a different pattern, with a sudden significant alteration in the levels of lactate, alanine, and glutamine at the time of terminal CM. In NCM, there were significant decreases with time of glutamate, the osmolyte myo-inositol, and glycerophosphocholine. These results are consistent with an ischemic change in the metabolic pattern of the brain in CM mice, whereas in NCM mice the changes were more consistent with hypoxia without vascular obstruction. Mild obstructive ischemia is a likely cause of the metabolic changes during CM, but a role for immune cell effector molecules cannot be ruled out.

Medtronic Mosaic porcine bioprosthesis: midterm investigational trial results

BACKGROUND

The midterm clinical and hemodynamic performance of the Medtronic Mosaic porcine bioprosthesis was evaluated in a regulatory trial.

METHODS

In nine Canadian centers, 802 bioprostheses (560 aortic and 242 mitral) were implanted between September 1994 and April 1999 in patients with a mean age of 70 years.

RESULTS

Survival for aortic valve replacement at 4 years was 84.4%+/-3.1%. Freedom from valve-related or unexplained death was 95.6%+/-1.9%; structural valve deterioration, 100.0%; reoperation, 96.2%+/-1.7%; major thromboembolism, 96.1%+/-1.8%; and major antithrombotic-related hemorrhage, 96.4%+/-1.7%. Echocardiographic derived mean systolic gradient was 13.4 mm Hg at 4 years with an indexed effective orifice area of 0.7 to 0.8 cm2/m2. A significant decrease in left ventricular mass was shown over time in all valve sizes. Survival for mitral valve replacement at 4 years was 79.2%+/-6.8%. Freedom from valve-related or unexplained death was 96.5%+/-3.4%; structural valve deterioration, 100%; reoperation, 97.0%+/-3.2%; major thromboembolism, 95.7%+/-3.8%; and major antithrombotic-related hemorrhage, 95.0%+/-4.2%. Echocardiographically measured averaged mean diastolic gradient was 4.5 mm Hg.

CONCLUSIONS

The Medtronic Mosaic bioprosthesis is safe and effective in both the aortic and mitral positions. The valve has low gradients in both positions and excellent left ventricular mass regression in the patients with aortic valve replacement.

Dichloroacetate (DCA) reduces brain lactate but increases brain glutamine in experimental cerebral malaria: a 1H-NMR study

Recent findings that levels of brain lactate and alanine were elevated in murine cerebral malaria led us to investigate the effect of dichloroacetate (DCA; 60 mg/kg), an activator of pyruvate dehydrogenase, on the levels of brain metabolites, and on the survival of mice infected with Plasmodium berghei ANKA which normally causes lethal cerebral malaria. DCA significantly reduced brain lactate and alanine levels when administered to infected mice, had no effect on the TCA cycle-related metabolites glutamate, GABA and aspartate and was associated with increased brain glutamine levels: 40% of mice thus treated survived the normally lethal infection.

Endothelin receptor blockade improves endothelial function in human internal mammary arteries

OBJECTIVE

Endothelial dysfunction, specifically endothelium-derived contracting factors have been implicated in the development of arterial conduit vasospasm. The potent vasoconstrictor endothelin-1 (ET-1) has received much attention in this regard. The present study was designed to evaluate the role of ET-1 in the development of endothelial dysfunction in human internal mammary arteries (IMA). To this aim, we examined the effects of specific and non-specific ET-receptor antagonists on endothelial function (assessed using acetylcholine (ACh)-induced vasodilation) in segments of IMA obtained during coronary artery bypass graft (CABG) surgery.

METHODS

Vascular segments of IMA were obtained from 51 patients undergoing elective coronary artery bypass graft (CABG) surgery and in vitro endothelium-dependent and -independent responses to ACh and sodium nitroprusside (SNP) were assessed. Isometric dose response curves (DRC) to ACh and SNP were constructed in pre-contracted rings in the presence and absence of bosentan (ET(A/B) receptor antagonist, 3 microM), BQ-123 (ET(A) antagonist, 1 microM) and BQ-788 (ET(B) antagonist, 1 microM) using the isolated organ bath apparatus. Percent maximum relaxation (%E(max)) and sensitivity (pEC(50)) were compared between interventions.

RESULTS

ACh caused dose-dependent endothelium-mediated relaxation in IMA (%E(max) 43+/-4, pEC(50) 6. 74+/-0.12). In the presence of bosentan, BQ-123 and BQ-788 ACh-induced relaxation was significantly augmented (%E(max) bosentan 60+/-3, BQ-123 56+/-4, BQ-788 53+/-5 vs. control 43+/-4, P<0.05) without affecting sensitivity. The effects of these antagonists were endothelium-specific since endothelium-independent responses to SNP remained unaltered. Furthermore, the beneficial effects were independently and maximally mediated by ET(A) and ET(B) receptors (%E(max) BQ-123 56+/-4 vs. BQ-788 53+/-5 vs. bosentan 60+/-3, P>0. 05).

CONCLUSIONS

These data uncover, for the first time, beneficial effects of ET receptor blockade on endothelial-dependent vasorelaxation in human IMA.

Tetrahydrobiopterin improves endothelial function in human saphenous veins

OBJECTIVES

Diminished production of nitric oxide has been linked to saphenous vein endothelial dysfunction. Tetrahydrobiopterin is an obligate cofactor for the oxidation of L -arginine by nitric oxide synthase in the production of nitric oxide by endothelial cells. The objective of the present study was to examine whether the exogenous addition of tetrahydrobiopterin improves endothelial function in saphenous veins from patients undergoing coronary artery bypass graft operations.

METHODS

Vascular segments of saphenous veins were obtained from 17 patients undergoing elective coronary artery bypass grafting, and in vitro endothelium-dependent and endothelium-independent responses to acetylcholine and sodium nitroprusside were assessed. Isometric dose-response curves were constructed in precontracted rings in the presence and absence of tetrahydrobiopterin (0.1 mmol/L) with the use of the organ bath apparatus. The percentages of maximum relaxation and sensitivity were compared between interventions.

RESULTS

Acetylcholine caused dose-dependent endothelium-mediated relaxation in saphenous veins. In the presence of tetrahydrobiopterin, acetylcholine-induced relaxation was significantly augmented (percentage maximum relaxation, 16.8% +/- 2.9% vs control 7.5% +/- 1.8%; P =.003) without an effect on agonist sensitivity. These effects were endothelium-specific because endothelium-independent responses to sodium nitroprusside were preserved.

CONCLUSIONS

These data uncover beneficial effects of acute tetrahydrobiopterin addition on endothelial function in human vessels. Because endothelial dysfunction has been implicated in the development of graft failure, studies aimed at chronic delivery of tetrahydrobiopterin would be useful in determining the contribution of this cofactor toward saphenous vein atherosclerosis.

Aortic arch interruption associated with ruptured cerebral aneurysm

The authors present a case of aortic arch interruption in an adult, an anomaly that was discovered coincidentally during angiography for ruptured cerebral aneurysm. The presentation in adulthood with rupture of the aneurysm and the successful surgical treatment of both abnormalities are unusual.

A randomized comparison of a bipolar steroid-eluting electrode and a bipolar microporous platinum electrode: implications for long-term programming

Differences in acute and chronic pacing thresholds were compared in patients receiving either the Medtronic Model 4004 steroid-eluting lead or the Medtronic Model 4012 microporous platinum lead. Patients (n = 35) were randomized at the time of implant to receive either a steroid-eluting (n = 17) or a microporous (n = 18) lead. Pacing thresholds were determined within 24 hours and at 2, 4, 6, 12, 24, and 52 weeks postimplant. By 2 weeks postimplant, pacing thresholds measured at 0.8, 1.6, 2.5, 3.3, and 4.2 V were significantly lower in the steroid lead group compared to the microporous lead group (P < 0.05). At 24 weeks, the voltage threshold at 0.3 msec was 0.8 V in 88% of patients with a steroid lead whereas this threshold was only observed in 33% of patients with the microporous lead (P < 0.01). At 52 weeks the pacing energy measured at 1.6 V, twice pulse duration threshold, was significantly lower in the steroid lead group (0.81 +/- 0.59 microJ) compared to the microporous lead group (1.25 +/- 0.60 microJ, P < 0.05). Thirteen patients in the steroid lead group and 9 patients in the microporous lead group have been programmed at a pulse amplitude of 1.6 V since the 24-week follow-up visit. These patients have been followed for a minimum of 6 months without documented failure to capture. This study shows that pacemaker/lead systems with stable chronic low thresholds can be safely programmed to low pulse amplitude settings. This practice will prolong the longevity of pulse generators.

Comparison of biphasic and monophasic shocks for defibrillation using a nonthoracotomy system

A comparison of defibrillation thresholds was made using biphasic and monophasic shocks delivered by a nonthoracotomy lead system in 2 clinically distinct groups of patients. The first group were patients receiving an implantable cardioverter-defibrillator who were studied before surgery with their chests closed. The second group were patients undergoing coronary artery bypass grafting (CABG) who were studied before surgery with their chests open but reapproximated. Biphasic defibrillation thresholds (stored energy) were significantly (p < 0.001) less than monophasic ones in subjects with the implantable cardioverter-defibrillator (12.3 +/- 5.3 vs 21.1 +/- 9.3 J) or CABG (14.6 +/- 7.1 vs 24.2 +/- 12.6 J). These values are less than were previously reported with a similar nonthoracotomy lead configuration. There were no significant differences between the 2 groups in all measurements derived from corresponding shock waveforms, although impedance tended to be greater in patients with CABG. However, subjects with CABG had greater left ventricular ejection fractions and did not have history of potentially lethal ventricular arrhythmias. Despite these differences, the conclusion that biphasic shocks are more effective would have been made in a study of either group alone. It is concluded that patients with CABG who have not had preceding potentially lethal ventricular arrhythmias may be a potential source of surrogate subjects for defibrillation research such as epicardial mapping, which requires that the chest be open.

Expression of metalloproteinases and their inhibitors in primary pulmonary carcinomas

Nine primary pulmonary carcinomas, one metastatic carcinoma, and two malignant pleural mesotheliomas have been analysed for the expression at the mRNA level of metalloproteinases (MPs) and tissue inhibitors of MPs (TIMPs). In situ hybridisation showed TIMP-1 and TIMP-2 transcripts predominantly over tumour stroma and gelatinases evenly distributed over both stromal and tumour cells. While both TIMP-1 and TIMP-2 were expressed in non-neoplastic lungs (NNL) as well as in carcinomas, stromelysin 3 (ST3), 92 kDa gelatinase and interstitial collagenase were expressed only by carcinomas. Expression of these MPs by carcinomas was independent of histologic type and such tumour features as fibrosis or necrosis. The consistent expression of ST3 by all of the carcinomas examined and absence of its expression in NNL indicates that ST3 production is likely associated with the malignant phenotype. However, since 92 kDa gelatinase and interstitial collagenase transcripts were found in some but not all tumour samples, their expression is not a uniform feature of pulmonary carcinomas. The possible prognostic significance of the expression of the latter two enzymes by carcinomas remains to be established.

Not all neonatal hearts are equally protected from ischemic damage during hypothermia

Despite hypothermia, pediatric cardiac surgeons continue to experience difficulties in providing adequate myocardial protection in newborns. This study examines the effects of deep hypothermia on neonatal heart tolerance to ischemia by measuring metabolic responses and the time to onset of ischemic contracture, or "stone heart." After control right ventricular biopsy specimens were obtained, hearts of newborn pigs (n = 36) were excised and placed in temperature-regulated baths: 37.5 degrees +/- 0.5 degrees C (n = 9), 19.0 degrees +/- 0.5 degrees C (n = 14), and 12.0 degrees +/- 0.5 degrees C (n = 13). With a compliant balloon in the left ventricle to measure pressure, time to onset of ischemic contracture (greater than 2-mm Hg rise) was recorded, and sequential biopsies were done. Data indicated hypothermia significantly (p less than 0.001) prolonged time to onset of ischemic contracture from 29.5 +/- 1.7 minutes (mean +/- standard error of the mean) at normothermia to 150.0 +/- 6.4 minutes at 19 degrees C and to 283.8 +/- 46.4 minutes at 12 degrees C. Lactate buildup at 30 minutes of ischemia was significantly reduced by 70% with hypothermia. Decline in adenosine triphosphate level was significantly reduced by 50% (19 degrees C) and 75% (12 degrees C) with hypothermia. More importantly, a subgroup of hearts in each hypothermia group (n = 5 per group) was identified by 38% to 48% lower adenosine triphosphate stores before ischemia compared with the group means.(ABSTRACT TRUNCATED AT 250 WORDS)

Myocardial abscess in a patient with AIDS-related complex: pericardial patch repair

A hemophiliac with acquired immunodeficiency syndrome-related complex was seen with sepsis related to a ventricular septal abscess. The abscess was debrided and the septum was patched with a single layer of autologous pericardium. The patient recovered and survived 6 months before dying of acquired immunodeficiency syndrome. At autopsy, the septal patch was well healed with no evidence of recurrent endocarditis.

Atenolol for the prevention of arrhythmias following coronary artery bypass grafting

Seventy patients undergoing aortocoronary bypass grafting were randomized, double-blind, to receive either atenolol or placebo. There were 35 patients in each group. Patients received either atenolol 5 mg intravenously or matching placebo within 3 h of the completion of surgery. A second intravenous dose was administered 24 h following the first and then atenolol 50 mg orally or matching placebo was given for six days. Continuous Holter monitor recordings were obtained for the 24 h immediately preoperatively and continuously for eight days postoperatively. No patient received any antiarrhythmic drug preoperatively. Patients who required pharmacological intervention for the management of postoperative arrhythmias were withdrawn as treatment failures. Holter monitor analysis continued for 24 h following withdrawal of a treatment failure. All patients were analyzed according to the intention-to-treat principle. Both groups were comparable with respect to age, sex, severity of coronary artery disease, left ventricular ejection fraction, preoperative use of beta-blockers, bypass time, aortic cross-clamp time, number of grafts per patient and frequency of preoperative arrhythmias. Arrhythmia analysis was done manually. Supraventricular arrhythmias (atrial tachycardia, atrial fibrillation and atrial flutter) were classified as either mild (less than 0.5 mins, less than 140 beats/min), moderate (0.5 to 30 mins, 140 to 180 beats/min), or severe (longer than 30 mins, more than 180 beats/min). Ventricular arrhythmia analysis was performed with respect to isolated PVCs, couplets, triplets and episodes of nonsustained ventricular tachycardia.(ABSTRACT TRUNCATED AT 250 WORDS)

Aorta-right atrial fistula: an unusual complication of ascending aortic dissection

Ascending aortic dissection complicated by aorta-right atrial fistula is a very rare occurrence. The patient may present with atypical clinical findings such as a continuous murmur or atrioventricular block, making the diagnosis difficult. Surgical repair is straightforward unless the correct diagnosis is missed, in which case there may be difficulties during the initial period of cardiopulmonary bypass. This report deals with the successful management of a 67-year-old man with this condition.

Effects of tricuspid regurgitation on thermodilution cardiac output: studies in an animal model

The thermal dilution technique (TD) of measuring cardiac output (Q) has been assumed to be inaccurate when the tricuspid valve is regurgitant (TR). The indicator transit time from the right atrium to pulmonary artery (PA) is prolonged and may increase indicator loss to the heart and adjacent tissue. We surgically created TR in four anaesthetized dogs and compared simultaneous cardiac output measurement made with an implanted PA flow probe with intermittent TD cardiac output measurements. We found an excellent correlation (r = 0.98) between the techniques in the normal heart when Q was increased by 100-150 per cent of control values using an intravenous dobutamine infusion. After TR was produced by incorporating the tricuspid valve leaflet within a suture, Q decreased. Dextran 40 was then infused and Q increased significantly. The rate at which Q increased was greater with the TD technique than with the PA flow probe; however, a significant (r = 0.85) linear relationship was still present with TR. The altered thermal waveform detected by the PA thermistor in TR was characterized by a lower peak amplitude and a slower return to baseline. Within the limitations of an animal model, our data suggest that TD cardiac output may be more accurate than previously assumed, particularly in low output states.

A method of treating serous fluid leak from a polytetrafluoroethylene Blalock-Taussig shunt

A 3 1/2-year-old girl with complex cyanotic congenital heart disease underwent palliation with a modified Blalock-Taussig shunt, for which a 6 mm polytetrafluoroethylene graft was used. Seroma formation with serous leakage occurred. Two periods of conservative management failed. At reoperation, treatment of the graft with intraluminal "fibrin glue" resulted in immediate resolution of the leak.

A rearing system for colostrum-deprived neonatal piglets

A system for the artificial rearing of colostrum-deprived neonatal piglets is described. A total of 443 piglets in 6 batches was reared. Each piglet, immediately after birth was placed in a separate incubator which was ventilated with heated filtered air. Piglets were fed hourly by an automatic system and were offered a liquid milk substitute. The mean survival rate up to the time piglets were transferred out of the rearing unit at 2 weeks of age was 78 +/- 7%. The mean daily live weight gain up to 2 weeks of age was 148 +/- 16 g/day and the dry matter intake over the same period was 154 +/- 10 g/day per piglet.

Enzyme-linked immunosorbent assay for the measurement of immunoglobulin G concentrations in porcine plasma and colostrum

An enzyme-linked immunosorbent assay is described for the estimation of porcine immunoglobulin G in either colostrum or plasma samples. The inter-assay coefficient of variation was 9.1 per cent and the intraassay coefficient of variation was 7.2 per cent. The repeatability or intra-class correlation coefficient of the assay was 0.9. The assay proved to be a sensitive, inexpensive and rapid method for assessing the immune status of pigs.

Changing the operative strategy for thyroid cancer by node sampling

One hundred fifty patients underwent thyroid surgery from 1979 to 1981, of whom 48 showed cancer for a 32 percent rate. In eight patients (16 percent), obvious clinical nodal disease was treated with modified neck dissection. Of the remaining 40 patients, internal jugular node sampling was carried out in 33, and revealed microscopic metastatic cancer in 12 patients who then underwent appropriate neck dissection. Node sampling increased our yield of nodal metastases from 16 to 42 percent, permitted one-hospitalization treatment, and afforded our patients the possibility of complete cancer control and prevention of the emergence of future recurrent disease. It is recommended that node sampling be incorporated into the operative strategy for thyroid cancer to permit intelligent selection of patients for modified neck dissection.

Macro--creatine kinase 2: a possible marker of gastrointestinal cancer?

Creatine kinase (CK) is an enzyme found in many body organs. It is used clinically in the diagnosis of myocardial infarction. Recently an atypical isoenzyme, macro-CK2, not found in the sera of healthy individuals, has been reported in patients with gastrointestinal malignancies. This study is a report of our findings in serum samples obtained from 200 patients from November 1981 until December 1982. Twenty-eight patients had gastrointestinal complaints but did not have malignant disease. One hundred seventy-two patients had malignancy. Samples of serum were studied for macro-CK2 with a standard laboratory agarose gel electrophoresis technique. The tests were done without knowledge of the patients' diagnoses. The results show no detectable macro-CK2 in sera from patients without malignancy. It was present before operation in nine of 13 patients with colorectal cancer and 16 of 21 patients with metastases from colorectal cancer or gastric cancer. This preliminary study suggests that the presence of macro-CK2 in serum may be an indicator of malignancy of the gastrointestinal tract and in particular of colorectal cancer.

Arthroscopic findings in the frozen shoulder

We report 24 patients with a clinical diagnosis of frozen shoulder who underwent an arthroscopic examination and were reviewed. A painful and stiff shoulder was present for an average of 8 months prior to the arthroscopy. The examinations were performed under general anesthesia and through a posterior route. The capacity of the genohumeral joint was measured by infiltration of physiologic saline and it was subnormal in almost 60% of the cases. Only 1 rupture of the rotator cuff was noted which had been previously demonstrated by arthrography. A torn long head of biceps was identified in 2 cases. No intraarticular adhesions were noted. These observations implicate an extra-articular cause for this clinical entity.