Handmaidens and pioneers: Three female anaesthetists and their contribution to anaesthesia in South Africa.

The period during and after World War II saw enormous changes in the practice and status of anaesthesia, as well as in female participation. This article offers an account of three South African (SA) women who trained in anaesthetics before and during the War and participated in these changes. By the mid-1960s, they presided over the three independent anaesthetic departments at Johannesburg's three main teaching hospitals, teaching generations of junior doctors. The first woman to register as a specialist anaesthetist in SA, Miriam (Mollie) Barlow, broke the glass ceiling in her own career by lobbying for the professional rights of medical women, although working within the constraints of the medical and political establishment. She also contributed to important SA research on malignant hyperthermia. Hilde Ginsberg collaborated with Barlow in the 1950s, reducing intraoperative and perioperative mortality at Coronation Hospital, and fought for key interventions in anaesthetic practice and policy through the South African Society of Anaesthetists (SASA), becoming its most long-serving and honoured female member. Kathleen Barbara Vetten's exemplary career in academic medicine, including pioneering animal research (developing anaesthetic techniques for open-heart surgery in dogs and protocols for liver transplantation in primates) and a successful operation to separate craniopagus twins, shows both the achievement of and limits to female achievement at the end of this period. This article also offers a short account of factors that hindered black women from entering anaesthesia training, contributing to this history before the 1990s.

Mechanisms of restenosis and redilation within coronary stents--quantitative angiographic assessment.

OBJECTIVES: This study was designed to assess the relative contributions of intimal hyperplasia and stent compression to the lumen narrowing seen after intracoronary stenting and to determine whether the lumen enlargement produced by angioplasty of in-stent restenosis results primarily from compression or extrusion of intimal hyperplasia through the stent or from additional stent expansion. BACKGROUND: Palmaz-Schatz stent placement outwardly displaces plaque and eliminates elastic vessel recoil to provide a large and smooth lumen. Some degree of late lumen narrowing occurs within each stent and causes significant restenosis (> or = 50% stenosis) in 25% to 30% of treated lesions. It has not been clear, however, whether this narrowing results from stent compression (crush) or from in-stent intimal hyperplasia. Because the Palmaz-Schatz stent has a distinct radiographic shadow, it is possible to determine the late diameter of both the stent and the enclosed vessel lumen to assess the relative contributions of these two processes. METHODS: From cineangiograms, initial (after stenting) and late (follow-up) lumen and stent diameters were examined in 55 patients (59 stents, group I) who had both immediate and 6-month (192 +/- 117 days) angiography. Lumen and stent diameter were also examined before and after dilation in 30 patients (30 stents, group II) who underwent angioplasty of severe in-stent restenosis. RESULTS: Late loss in minimal lumen diameter was 0.99 +/- 0.87 mm for group I despite only a slight (0.03 +/- 0.23-mm) reduction in the corresponding stent diameter. After redilation for in-stent restenosis, the acute gain in minimal lumen diameter was 1.51 +/- 0.82 mm for group II, again without appreciable increase (0.06 +/- 0.20 mm) in stent diameter. CONCLUSIONS: Restenosis after intracoronary Palmaz-Schatz stenting appears to be due predominantly to lumen encroachment by intimal hyperplasia within the stent, with minimal contribution of stent compression. Lumen enlargement after coronary angioplasty of in-stent restenosis appears to be due primarily to compression or extrusion of intimal hyperplasia through the stent, or both, rather than to further stent expansion.

Acute and nine-month clinical outcomes after "suboptimal" coronary stenting: results from the STent Anti-thrombotic Regimen Study (STARS) registry.

OBJECTIVES: This registry collected the 30-day and 9-month clinical outcomes of patients whose coronary stent implantation was suboptimal, and compared them with the cohort of patients with "optimal" stenting in the randomized portion of the STent Anti-thrombotic Regimen Study (STARS) trial. BACKGROUND: Although "optimal" stenting combined with an aspirin and ticlopidine regimen carries a low (0.5%) incidence of subacute stent thrombosis, only limited data are available for patients in whom stents are deployed suboptimally. METHODS: In the STARS, 312 (15.9%) of 1,965 patients enrolled were excluded from participation in the randomized trial based on a perceived "suboptimal" result of coronary stenting. Of these, 265 patients met prespecified criteria for suboptimal stenting, and were followed in a parallel registry, which was compared with the randomized STARS optimal stenting cohort. The primary end point was a 30-day composite of death, emergent target lesion revascularization, angiographic thrombosis of the target vessel without revascularization and nonfatal myocardial infarction (MI) unrelated to direct procedural complications. RESULTS: Registry patients had a similar frequency of the primary end point compared with the overall randomized cohort (3.0% vs. 2.2%), with this end point correlating to use of multiple stents, smaller final lumen diameter and absence of ticlopidine from the poststent regimen. Overall 30-day mortality (1.1% vs. 0.06%, p = 0.009) and periprocedural non-Q wave MI (8.7% vs. 4.2%, p = 0.003) were more frequent in registry patients, and appeared to be related to acute procedural complications. Clinical restenosis was significantly higher for registry patients (26.8% vs. 16.0%, p = 0.001), relating to greater prevalence of independent predictors such as smaller final lumen diameter and multiple stent use. CONCLUSIONS: In the STARS registry, the inability to perform optimal stenting correlated with smaller final lumen diameter and longer stent length. With ticlopidine-containing regimens, the acute clinical results of "suboptimal" stent deployment are clinically acceptable, although they are not quite as good as those of optimal stenting using similar drug therapy.

Cardiogenic shock induced by cocaine in swine with normal coronary arteries.

OBJECTIVE: The aim was to test the hypothesis that acute intravenous cocaine administration can cause coronary microvascular constriction culminating in myocardial ischaemia and cardiogenic shock. METHODS: Systemic haemodynamic variables and coronary blood flow were measured in 14 Yorkshire swine at baseline and following intravenous administration of 1, 3, and 10 mg.kg-1 of cocaine. Epicardial coronary artery diameter was measured from coronary arteriograms and coronary flow velocity was recorded with a Doppler flow wire. RESULTS: Cocaine produced a decrease in mean arterial pressure (65%), cardiac output (80%), and stroke volume (80%), and an increase in pulmonary artery diastolic pressure (60%). Although coronary blood flow decreased by 70%, epicardial coronary cross sectional area decreased by only 37-45%. Pretreatment with prazosin did not abolish the decrease in coronary blood flow. After administration of 10 mg.kg-1 of cocaine, five of 14 animals developed myocardial ischaemia and cardiogenic shock, culminating in ventricular fibrillation and death. CONCLUSIONS: In anaesthetised Yorkshire swine, cumulative intravenous doses of cocaine caused a significant reduction in coronary blood flow resulting in myocardial ischaemia, which cannot be attributed to epicardial vasoconstriction alone. This suggest that cocaine-induced coronary ischaemia may result from microvascular constriction, which is only partially prevented by alpha 1 blockade. In addition, direct toxic effects of cocaine on the myocardium may also contribute to the development of cardiogenic shock.

Is 40% to 70% diameter narrowing at the site of previous stenting or directional coronary atherectomy clinically significant?

Traditional binary definitions of coronary restenosis based on 6-month continuous angiographic measurements (e.g., > 50% diameter stenosis) may give confusing results for lesions whose late percent stenosis falls near the arbitrary threshold. To determine the long-term clinical consequences of such lesions, the overall correlation between follow-up percent stenosis and the performance of subsequent ischemia-driven target vessel revascularization (triggered by significant angina or a positive exercise study result, or both) was examined in 443 consecutive lesions treated with directional coronary atherectomy or Palmaz-Schatz coronary stenting. Follow-up angiograms (available in 355 lesions, 82%) were stratified into 3 groups: severe late stenosis (> 70% stenosis, n = 59), moderate late stenosis (40% to 70% stenosis, n = 72), and minimal late stenosis (< 40% stenosis, n = 224). With an average clinical follow-up of 933 +/- 394 days, 92% of lesions in the "severe late stenosis" group were treated with ischemia-driven target vessel revascularization, compared with 0% of the lesions in the "minimal late stenosis" group. Ischemia-driven target vessel revascularization was performed in 38% of patients in the "moderate late stenosis" group. However, patients in this group who did not undergo revascularization (despite the fact that 43% of them had a late stenosis of > 50%) showed a similarly favorable long-term clinical outcome to patients with a minimal late stenosis. These results support a strategy of conservative management for the 20% of patients who have a moderate (40% to 70%) late stenosis after stenting or atherectomy, but do not have evidence of ischemia.

Balloon postdilation can safely improve the results of successful (but suboptimal) directional coronary atherectomy.

This study investigates whether adjunctive balloon angioplasty can be safely used to improve acute results in cases where directional coronary atherectomy alone has provided a successful (but suboptimal) outcome. Between October 1, 1990, and October 1, 1992, directional coronary atherectomy was performed successfully in 198 of 228 lesions. Individual operators believed that most acute results were satisfactory after atherectomy alone (group I, n = 115) with a minimal lumen diameter that increased from 0.82 +/- 0.45 to 3.21 +/- 0.65 mm after atherectomy, for an acute gain in lumen diameter of 2.39 +/- 0.73 mm and a residual stenosis of 6 +/- 13%. In 42% of lesions (group II, n = 83), however, results were considered suboptimal after atherectomy alone, with a minimal lumen diameter that increased from 0.85 +/- 0.45 to 2.83 +/- 0.64 mm, a smaller acute gain of 1.96 +/- 0.72 mm, and a mean residual stenosis of 17 +/- 14% (although all residual stenoses were < 50%, 19% had a residual stenosis > 30%). Adjunctive balloon angioplasty in these group II lesions provided an additional gain of 0.34 +/- 0.38 mm, bringing the total acute gain for group II lesions to 2.32 +/- 0.78 mm and the residual stenosis to 9 +/- 13%, similar to that of group I patients who underwent atherectomy alone. This strategy resulted in a 7 +/- 13% overall residual stenosis for the study population, with no higher incidence of periprocedural complications or adverse late clinical outcomes in group II patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Intuitive knowledge of linguistic co-reference.

The research reported here is a systematic investigation of what competent, native speakers of English, native to contemporary syntactic theory, judge to be grammatically acceptable patterns of co-reference involving names and pronouns. Its central goal is the specification of syntactic factors that influence co-reference within and between sentences. The results show that naive subjects have consistent intuitions of grammaticality that agree with some principles of contemporary binding theory. The results also show that naive subjects diverge substantially from syntactic theorists in other judgments of grammaticality. In particular, subjects have strong intuitions that reflexives and pronouns are in complementary distribution, a fact that supports contemporary syntactic theory. Beyond that domain, subjects' judgments of co-reference in name-pronoun, name-name, and pronoun-name sequences are systematically influenced by syntactic structure in ways that are not consistent with syntactic theory. Co-reference in name-pronoun sequences is generally quite acceptable but becomes more acceptable as the syntactic prominence of the name increases. Co-reference in name-name sequences is only moderately acceptable and becomes less acceptable as the syntactic prominence of the first name increases. Co-reference in pronoun-name sequences is generally unacceptable and is only weakly influenced by the kinds of syntactic prominence that affect other relations of co-reference. We account for these results through the elaboration of a model of the process by which syntactic representations are mapped onto a representation of discourse capable of expressing generalizations about co-reference both intra-sententially and inter-sententially.

Perceptual-motor processing of phonetic features in speech.

Some reaction time experiments are reported on the relation between the perception and production of phonetic features in speech. Subjects had to produce spoken consonant-vowel syllables rapidly in response to other consonant-vowel stimulus syllables. The stimulus syllables were presented auditorily in one condition and visually in another. Reaction time was measured as a function of the phonetic features shared by the consonants of the stimulus and response syllables. Responses to auditory stimulus syllables were faster when the response syllables started with consonants that had the same voicing feature as those of the stimulus syllables. A shared place-of-articulation feature did not affect the speed of responses to auditory stimulus syllables, even though the place feature was highly salient. For visual stimulus syllables, performance was independent of whether the consonants of the response syllables had the same voicing, same place of articulation, or no shared features. This pattern of results occurred in cases where the syllables contained stop consonants and where they contained fricatives. It held for natural auditory stimuli as well as artificially synthesized ones. The overall data reveal a close relation between the perception and production of voicing features in speech. It does not appear that such a relation exists between perceiving and producing places of articulation. The experiments are relevant to the motor theory of speech perception and to other models of perceptual-motor interactions.

Lexical and prelexical influences on word segmentation: evidence from priming.

The authors examined the interaction of acoustic and lexical information in lexical access and segmentation. The cross-modal lexical priming technique was used to determine which word meanings listeners access at the offsets of oronyms (e.g., tulips or two lips) presented in connected speech. In Experiment 1, participants showed priming by the meaning of tulips when presented with two lips. In Experiment 2, priming by the meaning of the 2nd word was found in such sequences (e.g., lips in two lips). Finally, Experiment 3 demonstrated that listeners do not show priming by lips when it is pronounced as part of tulips. The results of these experiments show that listeners sometimes access words other than those intended by speakers and may simultaneously access words associated with several parses of ambiguous sequences. Furthermore, the results suggest that acoustic marking of word onsets places constraints on the success of lexical access. To account for these results, the authors propose a new model of lexical access and segmentation.

Acute and long-term results of coronary stents and atherectomy in women and the elderly.

AIM: To determine the efficacy of new coronary interventions in women and the elderly. PATIENTS AND METHODS: We studied 504 patients who underwent a total of 567 procedures, comprising 275 directional coronary atherectomy and 292 Palmaz-Schatz stents over a 2 1/2 year period; 18% were women and 23% were aged > or = 70 years (elderly). RESULTS: High rates of success were obtained with these procedures in women and the elderly, although the rates were lower in women than in men (89 versus 96%, P = 0.005), and similarly lower in the elderly than in younger patients (91 versus 96%, P = 0.06). In addition to the lower success rates, there was a higher incidence of procedure-related non-Q myocardial infarction and vascular complications in both the women and the elderly, independently. The degree of angiographic restenosis (> or = 50% diameter stenosis), however, was similar in women (36 versus 28% in men, P = 0.22) and in the elderly (28 versus 29% in patients ages < 70 years, P = 0.8). There were no sex-related differences in survival, late myocardial infarction, or repeat revascularization. In the elderly, although the incidence of repeat revascularization was not increased, there was a decrease in late survival (P < 0.001) and an increase in the incidence of late myocardial infarction (P = 0.02), probably reflecting the presence of other co-morbid variables. CONCLUSION: Both directional coronary atherectomy and coronary stenting can be performed safely and effectively in women and the elderly with good long-term clinical results, despite a somewhat lower rate of success and similarly higher rates of acute complications.

Language comprehension and probe-list memory.

Experiments were performed using probe-word recognition methodology in which participants read sentences that were presented 1 word at a time and were then shown a probe word and had to make a speeded response indicating whether the word had occurred in the sentence. One experiment showed that response times to probe words increased with the size of the set of candidate probes. The other experiments showed that the effects caused by name repetition in circumstances in which the repeated name was co-referential also occurred when the repeated name was not co-referential and when the order of words in a sentence was scrambled. The results suggest that responses in the task can be based on probe-list memory, a mental representation created to keep track of those words that the participant believes are likely to be probed, and that the use of the task to make inferences about language comprehension should be accompanied by controls ruling out such strategies.

Memory interference during language processing.

The authors studied the operation of working memory in language comprehension by examining the reading of complex sentences. Reading time and comprehension accuracy in self-paced reading by college students were studied as a function of type of embedded clause (object-extracted vs. subject-extracted) and the types of noun phrases (NPs) in the stimulus sentences, including relative clauses and clefts. The poorer language comprehension performance typically observed for object-extracted compared with subject-extracted forms was found to depend strongly on the mixture of types of NPs (descriptions, indexical pronouns, and names) in a sentence. Having two NPs of the same type led to a larger performance difference than having two NPs of a different type. The findings support a conception of working memory in which similarity-based interference plays an important role in sentence complexity effects.

Myocardial stunning in hyperthyroidism.

The cases of two patients with hyperthyroidism and acute left ventricular (LV) dysfunction with segmental wall motion abnormalities resulting in heart failure are reported. Both had electrocardiographic changes mimicking ischemic coronary artery disease. Treatment with antithyroid medications, beta blockers, and angiotensin-converting enzyme inhibitors rapidly restored LV function. The rapid reversibility suggests a role for myocardial stunning, an important entity to recognize in hyperthyroidism since this form of LV dysfunction can be reversed with appropriate treatment.

Decreasing blood product requirements after orthotopic liver transplantation.

OBJECTIVES: To document the changing blood product transfusion requirements over time during the first 50 orthotopic liver transplantation (OLT) operations performed at Groote Schuur Hospital. DESIGN: The first 50 OLT operations were divided into three groups chronologically and blood transfusion requirements were compared across the three groups. SETTING: Groote Schuur Hospital, Cape Town. SUBJECTS: Forty-seven patients undergoing 50 OLT operations between October 1988 and September 1999. The majority of patients had end-stage chronic liver disease. Patients were divided chronologically into three groups of 16, 17 and 17 patients. OUTCOME MEASURES: The number of units of blood products transfused in each group was quantified. RESULTS: During the study period there was a significant decrease in the number of units of packed red cells, fresh frozen plasma (FFP) and platelets (but not cryoprecipitate) transfused intraoperatively. The median number of units of packed cells decreased from 13.5 in our first 16 patients (group 1) to 5.0 in our last 17 (group 3). The median number of units of platelets transfused was 9 in group 1 and 0 in groups 2 and 3. No platelets were transfused in our last 22 patients. The average cost of blood products transfused intraoperatively per patient in the three groups decreased from R13 034 in group 1 to R11 389 in group 2 to R7 396 in group 3. CONCLUSION: The number of units of blood products transfused during OLT operations has decreased since the programme started 13 years ago. The reasons include increased experience, the use of aprotinin to block fibrinolysis and the selective use of the thromboelastogram to monitor coagulation intraoperatively. OLT need no longer be regarded as wasteful of blood resources. Use of platelets to treat thrombocytopenia need not be empirical.

Surgery and anaesthesia in art: the contribution of Dorothy Kay.

Dorothy Kay, the acclaimed Irish-born Port Elizabeth artist, married Dr Hobart Kay, FRCSI, in Cape Town, South Africa, in 1910. She was an exceptional portrait painter, whose astute observation of detail and ability to empathise with her subject and convey character brought her much important work. Her traditional British realist-school style of painting, and ability to depict mechanical equipment accurately, led to several industrial commissions. In 1937 these skills combined to produce her largest painting, 'Surgery' which depicts a patient undergoing an abdominal operation in a Port Elizabeth hospital. The painting graphically captures the skill and care exhibited by the anaesthetist, together with the anaesthetic equipment used at that time. During the war Dorothy became an accredited war artist. Eight of her wartime paintings were purchased by the Union Government and are now housed in the Ditsong National Museum of Military History in Saxonwold, Johannesburg. Two of these paintings of medical interest are discussed. The first, entitled 'Operation in a Base Hospital, depicts surgery being performed in a base hospital and is very similar in composition to 'Surgery' The second, entitled 'Blood to Save Lives, portrays a volunteer donating blood.