Surgical Trainee Supervision During Non-Trauma Emergency Laparotomy in Rwanda and South Africa

OBJECTIVE

The primary objective was to describe the level of surgical trainee autonomy during non-trauma emergency laparotomy (NTEL) operations in Rwanda and South Africa. The secondary objective was to identify potential associations between trainee autonomy, and patient mortality and reoperation.

DESIGN, SETTING, AND PARTICIPANTS

This was a prospective, observational study of NTEL operations at 3 teaching hospitals in South Africa and Rwanda over a 1-year period from September 1, 2017 to August 31, 2018. The study included 543 NTEL operations performed by the acute care and general surgery services on adults over the age of 18 years.

RESULTS

Surgical trainees led 3-quarters of NTEL operations and, of these, 72% were performed autonomously in Rwanda and South Africa. Notably, trainee autonomy was not significantly associated with reoperation or mortality.

CONCLUSIONS

Trainees were able to gain autonomous surgical experience without impacting mortality or reoperation outcomes, while still providing surgical support in a high-demand setting.

Indications and Outcomes for Non-Trauma Emergency Laparotomy: A Comparison of Rwanda, South Africa, and the USA

BACKGROUND

Emergency conditions requiring exploratory laparotomy (EL) can be challenging. The objective of this study is to describe indications, outcomes, and risk factors for perioperative mortality (POMR) after non-trauma EL.

METHODS

This was a prospective study of patients undergoing non-trauma EL at four hospitals in Rwanda, South Africa, and the USA. Multivariate logistic regression was used to determine factors associated with POMR.

RESULTS

Over one year, there were 632 EL with the most common indications appendicitis (n = 133, 21%), peptic ulcer disease (PUD) (n = 101, 16%), and hernia (n = 74, 12%). In Rwanda, the most common indications were appendicitis (n = 41, 19%) and hernia (n = 37, 17%); in South Africa appendicitis (n = 91, 28%) and PUD (n = 60, 19%); and in the USA, PUD (n = 16, 19%) and adhesions from small bowel obstruction (n = 16, 19%). POMR was 11%, with no difference between countries (Rwanda 7%, South Africa 12%, US 16%, p = 0.173). Risk factors associated with increased odds of POMR included typhoid intestinal perforation (adjusted odds ratio (aOR): 16.48; 95% confidence interval (CI): 4.31, 62.98; p value < 0.001), mesenteric ischemia (aOR: 13.77, 95% CI: 4.21, 45.08, p value < 0.001), cancer (aOR: 5.84, 95% CI: 2.43, 14.05, p value < 0.001), other diagnoses (aOR: 3.97, 95% CI: 3.03, 5.20, p value < 0.001), high ASA score (score ≥ 3) (aOR: 3.95, 95% CI: 3.03, 5.15, p value < 0.001), peptic ulcer disease (aOR: 2.82, 95% CI: 1.64, 4.85, p value < 0.001), age > 60 years (aOR: 2.32, 95% CI: 1.41, 3.83, p value = 0.001), and ICU admission (aOR: 2.23, 95% CI: 1.24, 3.99, p value = 0.007). Surgery in the US was associated with decreased odds of POMR (aOR: 0.41, 95% CI: 0.21, 0.80, p value = 0.009).

CONCLUSIONS

Indications for EL vary between countries and POMR is high. Differences in mortality were associated with patient and disease characteristics with certain diagnoses associated with increased risk of mortality. Understanding the risk factors and outcomes for patients with EL can assist providers in judicious patient selection, both for patient counselling and resource allocation.

[Rhinophyma : Successful treatment with low-dose oral isotretinoin]

Rhinophyma is a form of rosacea and is often cosmetically disfiguring. There are various therapeutic ablation modalities. Surgery is often associated with down-time and side-effects. We describe successful treatment with low-dose isotretinoin as a safe alternative with a lower risk of complications. We also discuss the advantages and disadvantages of various therapeutic modalities.

NMR-spektroskopische Untersuchungen an Benzylisochinolin-Derivaten

NMR-spektroskopisch wurde festgelegt, daß aus 3-Methyl-papaverin unter den Bedingungen der Coralyn-Reaktion das 6′-Aceto-Derivat entsteht. Die Untersuchungen ergaben, daß weder in Benzylisochinolinen und 3.4-Dihydro-benzylisochinolinen noch in den Salzen dieser Verbindungen eine Benzyl-Benzal-Tautomerie vorliegt.

A new concept of cellular uptake and intracellular trafficking of long-chain fatty acids

Fatty acids are the main structural and energy sources of the human body. Within the organism, they are presented to cells as fatty acid:albumin complexes. Dissociation from albumin represents the first step of the cellular uptake process, involving membrane proteins with high affinity for fatty acids, e.g., fatty acid translocase (FAT/CD 36) or the membrane fatty acid-binding protein (FABPpm). According to the thus created transmembrane concentration gradient, uncharged fatty acids can flip-flop from the outer leaflet across the phospholipid bilayer. At the cytosolic surface of the plasma membrane, fatty acids can associate with the cytosolic FABP (FABP(c)) or with caveolin-1. Caveolins are constituents of caveolae, which are proposed to serve as lipid delivery vehicles for subcellular organelles. It is not known whether protein (FABP(c))- and lipid (caveolae)-mediated intracellular trafficking of fatty acids operates in conjunction or in parallel. Channeling fatty acids to the different metabolic pathways requires activation to acyl-CoA. For this process, the family of fatty acid transport proteins (FATP 1-5/6) might be relevant because they have been shown to possess acyl-CoA synthetase activity. Their variable N-terminal signaling sequences suggest that they might be targeted to specific organelles by anchoring in the phospholipid bilayer of the different subcellular membranes. At the highly conserved cytosolic AMP-binding site of FATP, fatty acids are activated to acyl-CoA for subsequent metabolic disposition by specific organelles. Overall, fatty acid uptake represents a continuous flow involving the following: dissociation from albumin by membrane proteins with high affinity for fatty acids; passive flip-flop across the phospholipid bilayer; binding to FABP(C) and caveolin-1 at the cytosolic plasma membrane; and intracellular trafficking via FABP(c) and/or caveolae to sites of metabolic disposition. The uptake process is terminated after activation to acyl-CoA by the members of the FATP family targeted intracellularly to different organelles.

The dentist's exposure to elemental mercury vapor during clinical work with amalgam

Continuous measurements of mercury vapor in the breathing zone of the dentist were made under ordinary clinical conditions. Fifty old amalgam fillings were removed and replaced by new ones. The mercury vapor measurements were performed by means of atomic absorption spectrophotometry. On the basis of the type of suction device used, the measurements were divided into seven groups, each of which consisted of a series of measurements. During the cutting, filling, and polishing operations the mean mercury vapor levels in the breathing zone of the dentist were in the range of 1-2 micrograms Hg m-3 air when proper mercury hygiene measures were taken. This is far below the currently valid threshold limit value (30 micrograms Hg m-3 air) in Sweden. The saliva extractor and the dental mirror-evacuator did not influence the mercury vapor levels when used together with the high-volume evacuator. However, when only a saliva extractor was used, the cutting of amalgam fillings caused highly fluctuating mercury vapor levels, which were 2-15 times higher than the threshold limit value.

Model of mercury vapor transport from amalgam restorations in the oral cavity

A model of the oral cavity was used as the basis for a discussion of the conditions prevalent during the transport of mercury vapor from amalgam restorations via the saliva to the gas phase of the oral cavity during respiration or during pumping of air through the mouth. It was found that the mercury diffusion rate through the saliva layer is independent of the air flow rate through the oral cavity. Mercury appears to be transported as atoms both in the aqueous phase of saliva and in the gas phase. The majority of the mercury atoms reaching the gas phase appears to originate directly from the surface of the amalgam restorations, passing through the saliva layer, while only a minority originates from mercury dissolved in the aqueous phase. The amount of mercury released per unit of time to the gas phase was shown to be independent of the air flow rate during respiration and pumping. Furthermore, the released mercury atoms are distributed partly to the gas phase, from which they are respired to the lungs and the environment, and partly to the saliva and the gastro-intestinal tract, by swallowing.

Accuracy of duplex scanning in the detection of stenosis after carotid endarterectomy

The results of duplex ultrasonography in grading stenosis after carotid endarterectomy (78 sites) were compared with those of contrast angiography in 71 patients studied for recurrent or contralateral occlusive disease of the carotid bifurcation. Duplex and angiographic studies were performed within one month of each other at a mean postoperative interval of 44 months (range 3 to 122 months). Stenosis of the common carotid (CCA) and internal carotid artery (ICA) was classified into five disease categories (normal or less than 15% diameter reduction [DR], 16% to 49% DR, 50% to 75% DR, greater than 75% DR, and occlusion). The overall accuracy of duplex scanning compared with angiography in predicting recurrent carotid bifurcation disease was 83%, a level of agreement similar to classification of disease involving the nonoperated, contralateral bifurcation (overall accuracy 87%). Recurrent stenosis (greater than 50% DR) or occlusion of the CCA or ICA after endarterectomy was identified with an accuracy of 97%. Overestimation of severity of recurrent stenosis accounted for 11 of 13 duplex classification errors (85%). Presence of moderate (30% to 50% DR) recurrent stenosis of the CCA, tortuosity of the ICA, and severe contralateral carotid bifurcation disease were associated with velocity spectra that predicted a more severe recurrent stenosis at the endarterectomy site compared with angiographic grading. The level of agreement between duplex scanning and angiography was comparable to the interobserver variability in angiographic interpretation. The accuracy reported justifies the use of duplex scanning to grade the severity of carotid bifurcation recurrent stenosis and to follow these lesions for disease progression.

Determination of the rate of release of intra-oral mercury vapor from amalgam

The experimental and analytical difficulties associated with the measurement of mercury vapor in the oral cavity are considerable. In the present paper, the objective was to measure the amount of intra-oral mercury vapor in subjects with amalgams, by means of two sets of equipment based on different functional principles. In addition, it was found that the type of mercury source prevalent in the oral cavity had to be evaluated. The measuring technique used to obtain correct results is discussed, and an evaluation of the conditions for the application of the measuring equipment available was made. It was found that the amount of mercury released from the oral cavity was time-dependent. Furthermore, the amount of mercury released with the time kept constant was almost independent of the pumping flow rate up to 8 L/min. It was found that the tissue, saliva, and the amalgam restorations were not depleted of mercury during the measuring time. The results of the Mercollector-Mercometer measurements carried out on seven subjects with nine or more occlusal surfaces restored with dental amalgam and on three subjects without any amalgam restorations revealed that the rate of mercury release was in the range 0.03-0.34 ng/sec in the former group and less than 0.01 ng/sec in the latter. Based on the experimental results and on theoretical considerations, it was concluded that the amount of mercury released per time unit is the only quantity measurable.

Classification of carotid bifurcation disease using quantitative Doppler spectrum analysis

Spectrum analysis of continuous-wave Doppler recordings from the region of the carotid bifurcation was used to classify the degree of stenosis in the internal (ICA) and external (ECA) carotid arteries. Measurements of systolic peak frequency, end-diastolic frequency, and the degree of spectral broadening were used to define five ICA disease categories: 0% to 15% diameter reduction (DR), 16% to 49% DR, 50% to 80% DR, greater than 80% DR, and occlusion. The results were compared to contrast arteriography in 122 patients (243 arteries). The agreement with angiography in classifying ICA stenosis was 82%. Doppler spectrum analysis identified 96% of hemodynamically significant disease (greater than 50% DR) in the ICA and ECA and 97% of ICA occlusions. Attention to the common carotid artery waveform and the ICA diastolic frequency improved the accuracy of predicting greater than 80% DR and occlusion of the ICA. Noninvasive classification of carotid bifurcation disease is useful in clinical decision making to select the angiographic technique most likely to accurately define disease morphology and to follow up patients for disease progression.