Academic literature on the topic 'Dissertations – Anaesthesiology and critical care'

Thesis (DSc)--Stellenbosch University, 2013.
AFRIKAANSE OPSOMMING: Hierdie DSc is fundeer op ‘n aantal aspekte rondom ‘n sentrale tema naamlik die algemene en streeksfunksie van die normale hart of die hart blootgestel aan die risiko van miokardiale isgemie. Die werk is oor ‘n bestek van 25 jaar gedoen en sluit in eksperimentele werk in groot en kleindiere sowel as data verkry in pasiënte. Hoofstuk 1 handel met globale en streeksfunksie in die normale hart met die klem op die meer moderne benadering tot die koppeling van die hart met die sirkulasie en effek van middels op die twee komponente. Hierdie hoofstuk het waardevolle inligting gegee t.o.v. fisiologie maar ook gehelp om die middels te kies vir daaropvolgende studies. Hoofstuk 2 bevat navorsing wat verwys na die hart met kroonaarstenose. Onder andere word gesteun op ‘n dieremodel van kroonaarstenose. Die hoofstuk sluit data in wat , as eerste en unieke bydrae, gewys het dat inhalasie narkose middels die reperfusie besering van die hart kan verminder. Hierdie data het spesifiek bygedra om die kliniese praktyk van narkose vir hierdie pasiënte te verander. Hoofstuk 3 verwys na werk gedoen om die hart gedurende elektiewe chirurgiese arres te oksigeneer. Die effektiwiteit van verskillende kardioplegiese vloeistofsamestellings is ook krities ontleed. Die vierde hoofstuk handel met ‘n ernstige kliniese probleem naamlik akute pulmonêre hipertensie. By pasiënte met akute long besering is hierdie verskynsel baiemaal die oorsaak van dood en of moeitevolle oksigenasie. Die werk het gelei tot beter insigte t.o.v. pasiënt hantering tot die punt dat baie van die pasiënte vandag gered kan word.
ENGLISH ABSTRACT: This thesis is based on a number of aspects with a central theme of global and regional cardiac function in the normal heart and the heart at risk of ischemia. It summarizes work done over 25 years and includes experimental work in large and small animals as well as data obtained from human clinical practice. Chapter one deals with global and regional heart function and especially the physiological concept of ventriculo-arterial coupling as a mechanism to explain and understand the effects of inter alia commonly used drugs. Chapter 2 summarizes work done in hearts with a coronary artery stenosis. One of the interesting ,and at that time, unique findings was that inhalation anesthetic drugs are effective in limiting the reperfusion injury of the heart. This insight helped to redirect techniques used to anaesthetize patients with coronary artery disease. The third chapter examines methods to improve myocardial oxygenation during elective surgical cardiac arrest. It also includes data showing that not all the cardioplegic solutions are equally effective. Chapter four deals with a significant clinical problem i.e. acute pulmonary artery hypertension. This condition is often responsible for patient death, or contributes to, difficult oxygenation in patients with acute lung injury. The work in this chapter assisted in understanding the pathophysiology of the condition and improved the management thererof. This insight, combined with progress in other areas in the pathology or acute lung injury, has led to many of the patients today surviving their illness.

Thesis (MMed)--Stellenbosch University, 2014.
ENGLISH ABSTRACT: Case Report - A case is described of central oxygen pipeline failure that occurred at a large academic hospital and its subsequent implications for managing the situation. Literature review - The literature review undertaken focused on the current state of affairs with regards to anaesthetic staff's knowledge of and preparedness for the management implications of central oxygen pipeline failure. The events I describe below demonstrate a significant deficiency in the staff’s understanding of and training for the crisis, which should be remedied to improve patient safety. Specific measures are suggested in the literature to prevent such incidents and guidelines are available to manage central oxygen pipeline failure. These are reviewed in this study. Recommendations - This study attempts to bring together the most critical aspects that need to be addressed to safely manage similar future incidents. Prevention should include measures to implement clearly stated disaster management plans and increased awareness with regards to the medical gas pipeline system (MGPS), simulation training, efficient alarm systems, personally conducted routine evaluations of equipment and emergency backup systems by anaesthesiologists and effective communication between hospital staff. Careful planning and successful coordination during maintenance and modification of the medical gas pipeline system, using piston-type or air-driven, rather than oxygen-driven, ventilators and optimal design of the hospital bulk oxygen system can contribute to reduce risks. In the event of central oxygen pipeline failure a specific sequence of actions should be taken by the anaesthesiologist and a clear institutional operational policy is described.
AFRIKAANSE OPSOMMING: Gevalsbeskrywing - 'n Geval van sentrale suurstoftoevoerversaking, wat plaasgevind het by 'n groot opleidingshospitaal, word bespreek. Daar word ook gekyk na die praktiese gevolge met betrekking tot die hantering van die situasie. Literatuurstudie - 'n Literatuurstudie is aangepak met die doel om te fokus op die huidige toedrag van sake betreffende narkosepersoneel se kennis en paraatheid in die hantering van sentrale suurstoftoevoerversaking. 'n Wesenlike gebrek aan begrip en opleiding aangaande hierdie onderwerp is geïdentifiseer – areas wat, met die nodige aandag, verbeter kan word ten einde die welstand van pasiënte te verseker. Spesifieke voorkomende maatreëls en hanteringsriglyne word voorgestel deur die literatuur en word gevolglik hersien in hierdie studie. Aanbevelings - Hierdie studie poog om kernaspekte aan te raak ten einde soortgelyke toekomstige voorvalle veilig en optimaal te kan hanteer. Voorkomende maatreëls behels onder meer die daarstelling van duidelik verstaanbare noodplanne, verbeterde bewustheid aangaande die mediese gaspypsisteem, simulasie-opleiding, doeltreffende alarmstelsels, effektiewe kommunikasie tussen hospitaalpersoneel, sowel as narkotiseurs wat self roetine-evaluasies van hul narkosetoebehore en -noodtoerusting uitvoer. Noukeurige beplanning en neweskikking tydens herstelwerk of werk aan die mediese gaspypsisteem, die gebruik van suierventilators (of dan lugaangedrewe in plaas van suurstofaangedrewe ventilators) en die optimale uitleg van 'n hospitaal se suurstoftoevoer, kan bydra om die risiko's te beperk. In die geval van sentrale suurstoftoevoerversaking behoort die narkotiseur stapsgewyse aksie te neem. 'n Duidelike institusionele noodbeleid word ook omskryf.

In title 12, 22, 11 are in subscript.
Thesis (PhD)--Stellenbosch University, 2002.
ENGLISH ABSTRACT: The aim of this study was to test a synthetic protein-free surfactant preparation, LPM-l, with the same chemical composition as commercially available Exosurf (Glaxo Wellcome), but containing in addition, a sugar, trehalose (TRE). Towards this end, a study was designed to firstly test the hypothesis that the true difference in acute physiological effects between a mixture of oppe, tyloxapol, hexadecanol and trehalose (LPM-l), and Exosurf, (Oppe, tyloxapol and hexadecanol) is zero, in a surfactantdeficient animal model. A second study addressed the physiological effects of oppe, hexadecanol, tyloxapol and trehalose (LPM-l) compared to treatment with trehalose (TRE) or saline, in order to determine (1) the contribution of TRE to the mixture of oppe, hexadecanol and tyloxapol, and (2) to assess the effect of the LPM-l surfactant replacement on the epithelial lining fluid composition by means of analysing bronchoalveolar lavage fluid. Thirdly, the effects of TRE and / or calcium were studied on the surface properties of oppe suspensions, by in vitro analysis using the ring detachment method of Du Nouy The in vivo research comprised of two studies, performed in randomised controlled fashion. In the first study, 24 New Zealand White adult rabbits were randomised into 4 groups, while in the second study, 15 animals were randomised into 3 groups. In the first in vivo study, three synthetic surfactants, LPM-l, Exosurf and LPM-2, and a saline group were tested. LPM-l is a new formulation that consists ofa mixture of Df'PC, TRE, hexadecanol and tyloxapol. LPM-2 is a formulation with a composition equivalent to that of commercially available Exosurf, prepared on site. In both studies animals were subjected to repeated lavage with large volumes of warm saline (25 ml/kg) in order to establish surfactant deficiency and acute lung injury. Five minutes after the last lavage, vehicle, i.e. surfactants LPM-l, Exosurf, or LPM-2, or saline, in the first in vivo study, and LPM-l, TRE or saline in the second in vivo study, was instilled, and the course of the animals followed over the next 3 hours. Ventilator settings were standardized before and after lavage. The effects of surfactant treatment on gas exchange (arterial Pa02, oxygenation index (Ol), arterial-alveolar oxygen (a/A) ratio), percentage calculated shunt, and total dynamic respiratory compliance (CRSdyn), and histopathological changes were compared with changes in saline treated controls. Arterial blood gases in 100% oxygen and CRSdynwere measured before and after lavage, at 15 minute intervals for the first 30 min, then at 60, 90, 120, and 180 min after vehicle instillation. Oxygenation improved to a similar extent after LPM-l and Exosurf instillation, surpassing that of LPM-2 or saline. Overall, intratracheal instillation of both Exosurf and LPM-l, rapidly improved the gas exchange and reduced the intrapulmonary shunt, but did not restore the lung to its pre-lavage condition. From the 2nd in vivo study it was evident that trehalose-only, was inefficient as a lung surfactant, failing to improve oxygenation indices or the calculated percentage shunt, or influencing respiratory compliance. The addition of the sugar, trehalose (TRE), to the on-site 'Exosurf mixture (LPM-2) brought the activity of the resultant LPM-l to the same level as that of commercial Exosurf, but failed to raise the activity above that of Exosurf. These physiological improvements were sustained for up to 3 hours. Saline-treated animals had no improvement in gas exchange despite management with variable PIP (to maintain a tidal volume of -1 0 ml / kg) and constant PEEP of 5 cm H20. In-vitro results, obtained by the Ou Nouy tensiometer, showed higher mean ordinate surface tension values for the OPPC-only and DPPC + TRE mixtures, and the slopes of their respective graphs smaller in magnitude than those of the other formulations, suggesting that these formulations had less surface tension-lowering capability than the other surfactants. At 20°C (20 mg / ml DPPC-surfactants) the mean ordinate values of OPPC and OPPC + TRE, 70.13 and 69.47 dyne / cm, respectively, were not significantly different from each other. The mean ordinate values of LPM-l and the formulation containing OPPC + TRE + tyloxapol + CaCh were lower, but similar, as were the values of LPM-2 (on-site Exosurf) and LPM-2 + CaCho Thus, three internally homogeneous subgroups could be identified which differed significantly, namely: DPPC and DPPC + TRE, LPM-2 and LPM-2 + CaCh, and DPPC + TRE + tyloxapol + CaCh and LPM-l. Similar conclusions apply to the ordinate values of the surfactants at 37°C, and to the mean slope values at 20°C, with the exception that the subgroups, LPM-2 and LPM-2 + CaCh, and LPM-l and OPPC + TRE + tyloxapol + CaCh are not so clearly separated. A similar analysis of mean slope values was performed. Here too a significant difference between substances was found, OPPC alone or in combination with TRE, again being significantly different from the other surfactants. The most prominent light microscopy findings of the lungs of animals included general lymphatic dilatation, congestion and lung polymorphonuclear infiltration, with no difference between study groups. Hyaline membranes were present in all surfactant groups, but significantly more so in the saline treated group. In the first in vivo study, the presence of neutrophils in the lung interstitiwn as well as alveoli, was a common finding in all of the study groups towards the end of the study protocol. A significant increase in the BAL-fluid neutrophil count occurred in all animals, concurrent with a significant decrease in the BAL macrophage count. No significant change occurred in the peripheral neutrophil count during the 3-hour study, suggesting recruitment of neutrophils from storage pools. Treatment with synthetic surfactant (LPM -1) did not have a significant effect on modifying the inflammatory response, since there was no significant difference in the BAL-derived cell counts between the LPM-1 and -saline groups. Epithelial damage was a consistent finding in all groups. The damage was more evident by electron microscopy examination and included hydropic changes, most readily observed in the mitochondria. The airspaces of study subjects showed the presence of oedema fluid. This luminal oedema appeared to be more prominent in the control group and LPM-2 (on site 'Exosurf') group. Organellar debris, probably originating from lysis of epithelial cells, was present, despite treatment with synthetic surfactant. The electron microscopical appearance of the epithelial-lined substance ("hyaline membranes") in the present study showed a marked variability within groups as well as within the same case. The majority of cases showed a mix of membrane types with both granular and fibrillar materials present within the same membrane. In some cases there were layering of the membranes into distinct bands. The instillation of LPM-l resulted in the formation of a slightly different type of epithelial lining fluid after lavage, when compared to the prelavage composition. The most pronounced changes occurred within the fatty acids, whilst the phosphatidylcholine values remained unchanged. Palmitic acid concentrations (C16:0) increased significantly, suggesting enrichment of the epithelial lining fluid after instillation of LPM-l. This increase in C16:0 was concurrent with significant decreases in the percentage C16:1, C18:0, and C18:2. In contrast to previous studies, we describe higher levels for phosphatidyldimethylethanolarnine (PEA). An explanation may be that the lipid identified as PEA, was in fact partly phosphatidylglycerol (PG)-a lipid whose accurate identification was precluded for technical reasons. After surfactant instillation, the PC/SM ratio, a reflection of the lecithin / sphingomyelin (LIS), decreased significantly in the TRE-group between the first and final lavage, but remained statistically unchanged in the animals treated with LPM-l or saline. The change in ratio was mainly accounted for by a decrease in BAL-fluid PC content together with a rise in SM content. A poor correlation existed between the BAL-derived PC/SM ratio and indices reflecting oxygenation status (a/A ratio, Ol), as well as the CRSdynat the time of the final lavage. In conclusion, the primary hypothesis was accepted, LPM-l performed similarly to Exosurf in vivo, improving oxygenation, but not CRSdyn.None was clearly superior to the other. Some questions remain. The reason why LPM-l (LPM-2 + TRE) did not behave in a superior manner, in vivo, to Exosurf, is partly unclear. This finding was somewhat surprising since the chemical composition of Exosurf and LPM-2 did not differ, and the addition of TRE to LPM-2 (on-site Exosurf), did improve the in vivo activity of the resultant LPM-l, above that of LPM-2. A possible explanation for observed differences in performance include methodological issues, i.e. the preparation of the on-site formulations, especially that of LPM-2 (on-site Exosurf), may differ from the way in which true commercial Exosurf is prepared.
AFRIKAANSE OPSOMMING: Die doel van die studie was om 'n sintetiese proteïn vrye surfaktant te ontwikkel en die produk te vergelyk met 'n kunsmatige surfaktant reeds in kliniese gebruik. Die bekende uit die literatuur en die onbekende van die produk wat evalueer sou word, lei op tot die samestelling van die nul hipotese van die PhD naamlik dat geen verskil in longfunksie sou gewys word tussen die toetsproduk en reeds gebruikte kommersiële surfaktant nie. Die hipotese was dat 'n suiker (trehalose), in kombinasie met Dipalmitoiel fosfatidielcholine (DPPC), gaswisseling en longfunksies sal verbeter vir 'n long met 'n lae surfaktant konsentrasie. Vir die studie is jong volwasse wit New Zealand konyne gebruik en is hulle met 'n gestandaardiseerde en menslike manier gebruik in eksperimentele werk. Die diere is onder intraveneuse narkose geplaas en verskillende kardiovaskulêre en pulmonologiese aspekte is gemeet. Die long surfaktant is uitgewas deur middel van fisiologiese soutoplossing wat tot liggaam temperatuur verhit is en daarna is die diere prospektief gerandomiseer tot eksperimentele groepe. Met vooraf bepaalde tydsintervalle is die fisiologiese metings herhaal en was die metings toegespits daarop om longmeganiese funksie en gasoordrag vermoë te evalueer. Lig mikroskopiese en elektron mikroskopiese studies is ook op die longe gedoen en verder is brongoalveolêre vloeistof ook ontleed. Die groepe met ondersoek was: I. oppe, heksadekanol, tyloxapol en trehalose (LPM-I). 2. oppe, heksadekanol, tyloxapol (LPM-2 :. LPM-I sonder trehalose). Hierdie is 'n proteïnvrye surfaktant plaaslik berei ( dieselfde samestelling as Exosurf). 3. Exosurf®. (Kommersiële preperaat reeds in gebruik). Hierdie is 'n proteïnvrye sintetiese surfaktant. 4. Trehalose, 'n non-reduserende disakklaried van glukose. Addisioneel is daar ook in vitro studies gedoen waann die oppervlakte spanmngs aktiwiteite van die verskillende surfaktant oplossings vergelyk is. Die statistiese analise is gedoen in samewerking met Prof. J. Maritz wat 'n unieke metode ontwikkel en gepubliseer het om herhalende veranderlikes op 'n statisties verantwoordbare manier te ontleed. In die eerste van die studies, is LPM-I, Exosurf®, fisiologiese soutoplossing en 'n plaaslik bereide "Exosurf" (LPM-2), met 'n chemiese samestelling identies aan dié van kommersiële Exosurf®, evalueer. In 'n tweede studie is die fisologiese effekte van LPM-I vergelyk met trehalose of fisiologiese soutoplossing om die volgende te ondersoek: 1) Die bydrae van trehalose tot 'n mengsel van oppe, heksadekanol en tyloxapol (LPM-2). 2) Die gevolg van LPM-l surfaktant toediening op die konyn se brongo-alveolêre vloeistof samestelling. 'n Derde, in vitro studie, het die oppervlaktespannings-effekte van trehalose en of kalsiumbyvoegings tot DPPC-oplossings gemeet deur middel van die ring metode van Du Nouy, In die eerste in vivo studie verbeter oksigenasie en persentasie longaftakking tot dieselfde mate na LPM-l en Exosurf® toediening en word die hipotese van die proefskrif bevestig. In die breë gesien, is die tydsprofiele van LPM-l en Exosurf® ten opsigte van oksigenasie en persentasie longaftakking statisties betekenisvol beter en van 'n sneller aard, as die tydsprofiele van dieselfde indekse na die toediening van fisiologiese soutoplossing of LPM-2. Die tydsprofiel van dinamiese longvervormbaarheid, na die toediening van LPM-I of Exosurf®, is dieselfde, maar betekenisvol beter as die vervormbaarheid na toediening van LPM-2 of fisiologiese soutoplossing. Alhoewel die oksigenasie indekse in die geval van LPM-l en Exosurf® betekenisvol verbeter oor die studietydperk, vind volkome herstel tot die basislynwaardes (voor spoeling) nie plaas nie. Bykomend, geen van die surfaktante het na toediening enige noemenswaardige verbetering in longvervormbaarheid tot gevolg gehad nie. Die rede vir die swakker vertoning van LPM-2 en Exosurf is onbekend en sal in opvolg studie ondersoek word. In die tweede in vivo studie is dit duidelik dat trehalose op sy eie, 'n oneffektiewe surfaktant is aangesien die preperaat na toediening geen verbetering teweegbring ten opsigte van oksigenasie indekse, persentasie longaftakking, of long-dinamiese vervormbaarheid nie. Die toevoeging van trehalose tot LPM-2, om LPM-l te lewer, neem wel die aktiwiteit van LPM-l tot dieselfde in vivo vlak as dié van kommersiële Exosurf®, maar slaag nie daarim om 'n hoër fisiologiese in vivo aktiwiteit as dié produk te bereik nie. Die diere wat met fisiologiese soutoplossing behandel is toon geen verbetering in enige fisiologiese parameter nie. Die in vitro resultate wat verkry is deur die Du Nouy tensiometer toon hoër gemiddelde ordinaat oppervlaktespannings waardes vir 'n formule wat slegs uit DPPC bestaan, asook vir 'n mengsel van DPPC + trehalose. Die helling van die grafieke van hierdie oplossings is ook kleiner as die van die ander formulas wat daarop dui dat DPPC op sigself, en DPPC + trehalose, weinig vermoë het om oppervlaktespanning te verminder. Daarteenoor verlaag die volgende oplossings die oppervlaktespanning ten opsigte van gedistilleerde water betekenisvol en wel in In konsentrasie afhanklike manier by beide 21°C en 3rc: LMP-I-, LPM-2-, DPPC + trehalose + tyloxapol + CaCf2-, en LPM-2 + CaCf2. Die prominentste ligmikroskopiese bevindinge van die longe van die diere sluit in: Algemene limfvat dilatasie, stuwing, en long neutrofiel infiltrasie. Betreffende hierdie histologiese bevindinge is daar geen verskille aangetoon tussen die groepe nie. Hialienmembrane was teenwoordig in al die groepe, maar betekenisvol meer in die groep wat fisiologiese soutoplossing ontvang as vervangingsterapie. In die tweede in vivo studie is daar 'n betekenisvolle styging in die neutrofiel- en daling in makrofaagtelling, van die brongoalveolêre vloeistof spoeling in al drie die groep aangetoon. Terselfdertyd vind geen noemenswaardige daling in die perifêre (sistematiese) neutrofieltelling plaas nie. Hierdie bevindinge dui daarop dat die brongoalveolêre selveranderinge toegeskryf kan word aan verwerwing van neutrofiele vanuit 'n longstoringspoel eerder as rekrutering vanuit die sistemiese sirkulatoriese poel. Surfaktant (LPM-l), behandeling het geen betekenisvolle vermindering in long inflammasie teweeggebring nie. Epiteelskade was 'n algemene ligmikroskopiese bevinding in al die groepe. Die samestelling van die brongoalveolêre vloeistof verander na installering van LPM-I. Die prominentste verandering word waargeneem in die vetsuur samestelling terwyl die DPPC waardes onveranderd bly. Die vetsuur, palmitiensuur (palmitic acid), (CI6:0), verhoog betekenisvol na toediening van LPM-l. Daarteenoor verminder die konsentrasie van C16:1, C18:0 en C18:2. In kontras met vorige studies, beskryf die huidige studie hoër konsentrasies van fosfatidieletanolamien, moontlik as gevolg van tegniese verskille in die metingsmetodes. 'n Betekenisvolle verlaging in die fosfatidielcholine:sfingomiëlien (PC/SM) verhouding word waargeneem tussen die eerste en die finale longspoeling van die trehalose-groep, terwyl dit onveranderd bly in die diere wat LPM-1 of fisiologiese soutoplossing ontvang.

Dissertation (MD)--Stellenbosch University, 2000.
ENGLISH ABSTRACT: Acute renal failure still is, with the exception of cardiac deaths, the most important pathological process associated with perioperative mortality in patients operated for abdominal aortic aneurysms. The intraoperative change in renal blood flow (RBF) and glomerular function have been investigated in human and animal models, particularly over the past 15 years. Despite large variation in study populations, measurement techniques and study designs in general, a significant body of evidence has developed which suggests infrarenal aortic clamp-induced renal ischemia to be the cause of postoperative acute renal failure when this complication does occur. It is rather surprizing then that, despite some recent studies which have reported on various pharmacological interventions to prevent intraoperative renal ischemia (with variable success), very little has apparently been done to unravel the pathogenesis and exact pathophysiology of this potentially lethal complication. Although a number of investigators suggest the possibility of hormonal involvement (particularly reninangiotensin, antidiuretic hormone (ADH) and catecholamines) in the process, the exact role of these mediators have not been explored (or reported) in a structured fashion. In an initial human study, renal hemodynamics and function were measured from the preoperative period, during the intraoperative phase and at least until 4 hours after aortic unclamping. To investigate the possibility of a temporal relationship between renal changes and fluctuations in hormonal concentrations, plasma concentrations of relevant hormones were determined at every sampling period where renal parameters were measured. The decrease in RBF and glomerular filtration rate (GFR) which we demonstrated to coincide with infrarenal aortic cross clamping, is consistent with results previously published. We demonstrated persistence of the impairment of these parameters as long as 4 hours into the postoperative phase; which has previously only been reported for the period until immediately after aortic unclamping with the abdomen still open. The persistence of a depressed GFR until the time of discharge of patients is cause for concern, particularly in patients with compromised renal function prior to surgery. Of the measured hormones with a potential influence on RBF and nephron function, renin was the only mediator where changes in plasma concentrations coincided with the depression of RBF and GFR after aortic cross clamping. The design of our study did not allow us to conclude whether the concomitant increase in angiotensin II was primarily responsible for the change in renal hemodynamics, or whether the raised renin (and angiotensin) levels were stimulated by the decrease in RBF induced by another mechanism. In another patient group, we demonstrated that the combination of mannitol and dopamine provided no protection against the deleterious effects of aortic cross clamping. In fact, the high urine volumes produced under the influence of these agents (which did not correlate with RBF at the corresponding periods), is likely to prompt a false sense of security. Given the lack of any objective benefit afforded by these agents, their use in these clinical circumstances should be discouraged. The animal studies were aimed at elucidation of the exact role of angiotensin in the pathogenesis and pathophysiology of the renal changes associated with infrarenal aortic clamping, as well as the interaction of angiotensin with other modulators for which an interactive relationship had been described previously under other experimental and/or clinical circumstances. The first study showed that, although renin (and thus angiotensin) concentrations were high after aortic unclamping, the hormone had no pathogenic or pathophysiological role of significance in the observed renal changes during this period (since blocking angiotensin II activation by the prevention of renin release, or by inhibiting the conversion enzyme, did not prevent a substantial decrease in RBF or GFR during that period). Preventing angiotensin II activation did, however, prevent renal changes during aortic clamping. This beneficial effect did not establish a primary role for angiotensin during that period, since the favourable influence could also (at least partially) be explained by prevention of the permissive influence of angiotensin on other vasoconstrictors and/or other vasodilatory influences of ACE inhibition and [1- blockade which are unrelated to angiotensin. This study did indicate that (at least partially) different mechanisms are responsible for the renal changes seen during aortic clamping, and after aortic unclamping. The second study explored the role of calcium in the renal pathophysiological changes during aortic clamping and after unclamping. The protective influence effected by the administration of a Ca2 + -blocker suggest the dependence of the renal vasoconstrictive and glomerular pathophysiological process( es) on the cellular influx of Ca2 + through voltage-gated channels. It unfortunately provides no definitive insight into the primary instigators of these processes. However, it does offer a clinically useful method of preventing these changes and protecting the kidney against ischemic injury during abdominal aortic surgery. The third component of the animal studies demonstrates the importance of the protective effect of renal prostaglandins during the specific experimental (and probably also the clinical) circumstances. Again, it does not provide definitive information on the mediators responsible for the renal changes, since the deleterious effects of numerous endogenous substances have previously been shown to be counterbalanced by intrarenal synthesis of prostaglandins under various experimental and clinical circumstances. The extent of the pathophysiological and ultrastructural changes which occurred under the influence of a NSAID does, however, suggest that these drugs should not be used under these clinical circumstances. The last component of the study provides evidence that angiotensin only plays a secondary/supplementary role in the renal pathophysiological process even during aortic clamping. This may explain the contradictory evidence regarding the potential beneficial effect of ACE inhibition (on renal hemodynamics and glomerular function) during abdominal aortic surgery (Licker et al. 1996, Colson et al. 1992a). Based on our studies, ACE inhibition can not be supported for this purpose.
AFRIKAANSE OPSOMMING: Akute nierversaking is met die uitsondering van kardiale sterftes, steeds die belangrikste patologiese proses wat geassosieer is met perioperatiewe mortaliteit in pasiënte wat opereer word vir abdominale aorta aneurismes. Die intraoperatiewe veranderinge in renale bloedvloei (NBV) en glomerulêre funksie is die afgelope 15 jaar ondersoek en gerapporteer in pasiënte- sowel as diere-modelle. Ten spyte van groot variasies in studie-populasies, meettegnieke en ontwerp van studies in die algemeen, dui 'n wesenlike hoeveelheid getuienis daarop dat infrarenale klemming van die aorta renale isgemie induseer, wat die oorsaak is van postoperatiewe akute nierversaking wanneer hierdie komplikasie voorkom. Dit is verbasend dat, ten spyte van sommige onlangse studies wat rapporteer oor 'n verskeidenheid farmakologiese ingrepe om intraoperatiewe renale isgemie te voorkom (met wisselende sukses), baie min oënskynlik gedoen is om die patogenese en die presiese patofisiologie van hierdie potensieel dodelike komplikasie te ontrafel. Hoewel verskeie outeurs die moontlikheid van hormonale betrokkenheid (veral renienangiotensien, antidiuretiese hormoon en katekolamiene) in hierdie proses suggereer, is die presiese rol van hierdie mediators nog nie op 'n gestruktureerde wyse ondersoek (of rapporteer) nie. In ons aanvanklike pasiënte-studie is renale hemodinamika en -funksie gemeet vanaf die preoperatiewe periode, gedurende die intra-operatiewe fase en tot minstens vier uur na ontklemming van die aorta. Serumkonsentrasies van relevante hormone is bepaal tydens elke metingsperiode waar renale parameters gemeet is, ten einde die moontlikheid van 'n temporale verwantskap tussen renale veranderinge en variasies in hormoonkonsentrasies te ondersoek. Die vermindering in NBV en glomerulêre filtrasiespoed (GFS) wat ons aangetoon het om saam te val met infrarenale aortaklemming, stem ooreen met resultate wat tevore deur ander navorsers publiseer is. Ons het aangetoon dat die inkorting van hierdie parameters voortduur tot minstens vier uur na aorta-ontklemming. Hierdie veranderinge is tevore slegs rapporteer vir periodes tot kort na aorta-ontklemming voor sluiting van die buikwond. Die feit dat die GFS steeds verlaag is met ontslag van hierdie pasiënte, skep rede tot kommer, veral in pasiënte wat alreeds ingekorte nierfunksie het voor die chirurgiese prosedure. Van die gemete hormone wat moontlik 'n invloed sou kon uitoefen op NBV eh nefronfunksie, was renien die enigste waarvan verandering in plasmakonsentrasies saamgeval het met die onderdrukking van NBV en GFS na aortaklemming. Die ontwerp van ons studie het ons nie toegelaat om 'n besliste uitspraak te maak of die geassosieerde verhoging in angiotensien II primêr verantwoordelik was vir die verandering in renale hemodinamika, of dat die verhoogde renien (en angiotensien) bloedvlakke moontlik sekondêr stimuleer is deur die verandering in NBV wat deur 'n ander meganisme induseer is. In 'n ander pasiëntegroep het ons aangetoon dat die kombinasie van mannitol en dopamien geen beskerming verleen het teen die nadelige effekte van aorta-klemming nie. Die groot volumes uriene wat uitgeskei is onder die invloed van hierdie middels (wat nie korreleer het met NBV tydens ooreenstemmende periodes nie), het inderwaarheid 'n ontoepaslike gerustheid uitgelok. Weens die ooglopende gebrek aan objektiewe voordeel wat verleen word deur hierdie middels, behoort hulle gebruik tydens hierdie kliniese omstandighede ontmoedig te word. Die doel van die diere studies was die identifisering van die presiese rol van angiotensien in die patogenese en patofisiologie van die renale veranderinge geassosieer met infrarenale aortaklemming, sowel as die interaksie van angiotensien met ander modulators waarvoor 'n interaktiewe verwantskap voorheen beskryf is onder eksperimentele en/of kliniese omstandighede. Die eerste studie het getoon dat alhoewel renien (en dus angiotensien) konsentrasies hoog was na aorta-ontklemming, die hormone geen betekenisvolle patogenetiese of patofisiologiese rol in die waargenome renale veranderinge gedurende hierdie periode het nie (aangesien blokkade van angiotensien aktivering deur voorkoming van renien vrystelling, of deur inhibisie van angiotensien omsettingsensiem (AOE), nie 'n daling in NBV of GFS kon voorkom nie). Voorkoming van angiotensien II aktivering het egter wel renale verandering voorkom gedurende aortaklemming. Dié voordelige effek het nie 'n primêre rol vir angiotensien gedurende die periode bevestig nie, aangesien die gunstige invloed ook (ten minste gedeeltelik) verduidelik kon word deur die voorkoming van die fassiliterende invloed van angiotensien op ander vasokonstriktore en/of ander vasodilator-invloede van die onderdrukking van AOE en ïs-blokkers (wat geen verband het met angiotensien of die blokkade daarvan nie). Die studie het aangetoon dat (ten minste gedeeltelik) verskillende meganismes verantwoordelik is vir renale veranderinge wat gesien is gedurende aortaklemming en na -ontklemming. Die tweede studie het die rol van kalsium in die renale patofisiologiese veranderinge gedurende aortaklemming en na ontklemming ondersoek. Die beskermende invloed wat deur die toediening van Ca2 + -blokkers bewerkstellig is, het bevestig dat die renale vasokonstriktoriese en glomerulêre patofisiologiese prosesse afhanklik is van sellulêre influks van kalsium deur spannings-afhanklike kannale. Dit het ongelukkig geen definitiewe insig verleen ten opsigte van die primêre inisieerders van die proses nie. Dit verskaf nogtans 'n bruikbare kliniese metode om daardie veranderinge te voorkom en die niere teen isgemiese besering gedurende abdominale aorta-chirurgie te beskerm. Die derde komponent van die diere-studies demonstreer die belangrikheid van die beskermende effek van renale prostaglandiene tydens die spesifieke eksperimentele (en waarskynlik ook die kliniese) omstandighede. Weereens gee dit nie definitiewe inligting oor die bemiddelaars wat verantwoordelik is vir die renale veranderinge nie, aangesien die skadelike effekte van verskeie endogene stowwe voorheen aangetoon is om beperk of voorkom te word deur die intrarenale vrystelling van prostaglandiene. Die omvang van die patofisiologiese en ultrastrukturele veranderinge wat ontstaan het onder die invloed van nie-steroïed anti-inflammatoriese middels (wat gebruik is om prostaglandien sintese te inhibeer), dui aan dat hierdie middels vermy moet word onder soortelyke kliniese omstandighede. Die laaste komponent van die studie verskaf 'n sterk aanduiding dat angiotensien slegs 'n sekondêre/aanvullende rol speel in die renale patofisiologiese proses, selfs gedurende aortaklemming. Dit mag die weersprekende getuienis oor die potensiële voordeel van AOE onderdrukking (op renale hemodinamika en glomerulêre funksie) gedurende abdominale aortachirurgie (Licker et al. 1996, Colson et al. 1992a) verklaar. Gebaseer op ons studies, kan AOE onderdrukking nie ondersteun word vir hierdie doel nie.

Thesis (MMed)-- Stellenbosch University, 2013.
ENGLISH ABSTRACT: Introduction: Of the volatile anaesthetic agents, desflurane causes the greatest degree of potentiation of the neuromuscular blocking drugs (NMB). The purpose of this study was to determine whether desflurane prolongs the effects of 3xED95 doses of rocuronium and cisatracurium to the same degree. The two NMB represent potent and less potent classes respectively. Methods: Informed, written consent was obtained from 63 adult patients scheduled for routine surgery. They were randomly allocated to one of four groups to receive either desflurane-sufentanil (end-tidal partial pressure 4.0 kPa) or propofol-sufentanil anaesthesia and either rocuronium (0.9mg/kg) or cisatracurium (0.15mg/kg). All patients received a target-controlled sufentanil infusion (0.5 ng/ml). Neuromuscular blockade was recorded using accelerometry (TOFGUARD ®, Organon) while patients recovered spontaneously to a Train-of-Four ratio of 0.9 (TOFR0.9). Data were analysed using one- and two-way analysis of variance. The main effects were the types of anaesthetic and NMB on indices of recovery. Results: Compared with propofol-sufentanil anaesthesia, mean times to recovery to T125% and TOFR0.9, were prolonged by desflurane-sufentanil (p<0.01). There were no interactions. Mean prolongation of time to TOFR0.9 was 41 min (SD 36) for cisatracurium and 26.6 min (SD 39) for rocuronium. Discussion: Whereas previous studies did not reveal prolongation of the duration of action of rocuronium by desflurane, we demonstrated a statistically significant prolongation of the spontaneous recovery times of both rocuronium and cisatracurium by desflurane. From the data we could not conclude that there was a difference between the two NMB. A power study revealed that in order to detect a difference between times to recovery to TOF0.9, a sample size of 101 subjects per group would be required. Conclusion: Desflurane prolongs the mean time to spontaneous recovery from neuromuscular blockade after 3xED95 doses of both cisatracurium (a potent NMB) and rocuronium (a less potent NMB). There was wide inter-individual variation in times to spontaneous recovery. Any difference in the mean prolongations between the different types of NMB is unlikely to be of clinical importance.
AFRIKAANSE OPSOMMING: Inleiding Van al die vlugtige narkosemiddels veroorsaak desfluraan die grootste mate van potensiasie van die neuromuskulêre blokkeermiddels. Die doel van hierdie studie was om vas te stel of desfluraan wel die effek van driedubbel die ED95 dosis van rokuronium en cisatrakurium tot dieselfde mate sal verleng. Metodiek Geskrewe ingeligte toestemming is verkry van 63 pasiënte wat voorgedoen het vir roetiene chirurgiese prosedures. Pasiënte is lukraak in een van vier groepe ingedeel om of desfluraansufentaniel (eind-gety parsieële druk 4.0 kPa) of propofol-sufentaniel narkose en of rokuronium (0.9 mg/kg) of cisatrakurium (0.15 mg/kg) te ontvang. Alle pasiënte het 'n teiken-beheerde sufentaniel infusie (0.5 ng/ml). Neuromuskulêre blokkade is waargeneem met behulp van aksellerometrie (TOF-GUARD, Organon) terwyl pasiënte spontaan herstel het tot “reeks-van-vier” verhouding (Engels “Train-of-four” ratio) 0.9 (TOFR0.9). Data analise is gedoen met behulp van een- en tweerigting analise van variansie. Resultate Desfluraan-sufentaniel het die gemiddelde hersteltyd tot T125% en TOFR0.9 verleng in vergelyking met propofol-sufentaniel. Geen interaksies is waargeneem nie. Gemiddelde verlenging van TOFR0.9 vir cisatrakurium was 41 minute (standaardafwyking 36) en vir rokuronium 26.6 minute (standaardafwyking 39). Bespreking Vorige studies kon nie vasstel of desfluraan die werkingsduur van rokuronium verleng nie. Ons het in hierdie studie vasgestel dat desfluraan wel 'n statisties beduidende verlenging in die hersteltyd van beide rokuronium en cisatrakurium veroorsaak. Ons kon egter nie 'n verskil tussen die twee neuromuskulêre agente aandui nie. 'n onderskeidingsvermoëstudie het getoon dat ten minste 101 pasiënte per groep benodig sou word om 'n beduidende verskil tussen die hersteltye tot TOFR0.9 te verkry. Gevolgtrekking Desfluraan verleng die gemiddelde hersteltyd tot spontane herstel van neuromuskulêre blokkade na driedubbele ED95 dosisse van beide cisatrakurium en rokuronium. Daar was egter groot interindividuele variasie ten opsigte van spontane hersteltyd. Enige verskille in die gemiddelde verlenging is onwaarskynlik van kliniese belang.

Thesis (MMed)--Stellenbosch University, 2014.
ENGLISH ABSTRACT: BACKGROUND Post anesthesia discharge criteria scoring systems have been used successfully to aid discharge from the post anesthetic care unit (PACU) for over 40 years. They do not replace, but rather act in conjunction with good clinical judgment, and provide concise, standardized documentation of a patient’s readiness for discharge. 1,2,3,4,5 In order to improve patient safety, provide clear documentation and to aid future audit, a discharge criteria scoring system was developed for use in our PACU (Addendum A). It is a modification of the Aldrete Scoring System and the modified Post Anesthetic Discharge Scoring System (PADSS) proposed by Chung.1 There is a steadily increasing patient burden on the existing medical infrastructure in South Africa. Tygerberg Academic Hospital is no exception, and because of the high demand on our theatre services, optimal efficiency is essential. We speculated that our discharge criteria scoring system might increase the efficiency of our PACU when compared to the traditional time based system. The more healthy patients, undergoing minor procedures, could potentially spend less time in PACU, allowing the nurses to focus on problem cases. Increasing the speed of transit might also help prevent delays in theatre due to lack of bed space in PACU. Our primary endpoint was to compare the duration of time spent by patients in the PACU at Tygerberg Academic Hospital, from the moment they are admitted, to the time they are discharged to the ward, before and after the introduction of a discharge criteria scoring system. While planning the audit, one of the factors that staff identified as contributing to delayed discharge from PACU, was the time it took for the wards to collect their patients. A secondary objective, therefore, was to assess the amount of time that elapsed between calling the ward to collect the patient, and the patient leaving PACU. METHODS AND MATERIALS Prior to commencing the audit, approval was obtained from the Human Research Ethics Committee of the Faculty of Health Sciences of the University of Stellenbosch and Tygerberg Academic Hospital. The Audit, its purpose and possible benefits, was discussed with representatives of the nurses working in PACU, and written consent was obtained from those who would be involved in the data collection (Addendum B). Audit forms (Addendum C), collection boxes, and posters reminding staff to participate in the audit were prepared. Our first audit was performed over approximately a week in August 2012. During this period, the traditional time-based discharge system was still in operation. Data was captured from 327 patients. Audit forms were placed in a collection box, which was cleared daily by the primary investigator. The discharge criteria scoring system was introduced to the PACU staff in January 2013. The nurses were trained in its use, and a one month period was allowed for all involved to become accustomed to the new system. A second audit was performed in February 2013, again over a week, during which we gathered data from 313 patients. RESULTS The median value of the time spent by patients in the PACU decreased from 1 hour 25 minutes, to 1 hour 15 minutes, after introduction of the discharge criteria scoring system. This was statistically significant (p-value = 0.003). The median time between calling the ward to collect a patient, and the patient leaving recovery, was 15 minutes. CONCLUSION The main finding of the study was that the introduction of a discharge criteria scoring system decreased the median duration of time spent by patients in the post anesthetic care unit at Tygerberg Academic Hospital.
AFRIKAANSE OPSOMMING: AGTERGROND Puntestelsels as ontslag kriteria na narkose, word vir die afgelope 40 jaar suksesvol gebruik as maatstaf om pasiënte uit die herstelkamer te ontslaan. Hierdie kriteria vervang nie goeie kliniese oordeel nie, maar is ’n addisionele hulpmiddel om te bepaal of die pasiënt gereed is vir ontslag en om noukeurige, gestandardiseerde dokumentasie te verseker. 1,2,3,4,5 'n Nuwe puntestelsel vir ontslag is vir die herstelkamer van Tygerberg Akademiese Hospitaal ontwikkel om pasiëntesorg en dokumentasie te verbeter, asook om ouditering in die toekoms te vergemaklik (Addendum A). Hiervoor is die Aldrete Scoring System en die gemodifiseerde PADSS, voorgestel deur Chung, aangepas. 1 Die bestaande mediese infrastruktuur in Suid-Afrika beleef tans ‘n geleidelike toename in die getal pasiënte. Tygerberg Akademiese Hospitaal is geen uitsondering nie en as gevolg van die hoë aanvraag na ons teaterdienste, is uiterste doeltreffendheid noodsaaklik. Ons vermoede was dat hierdie aangepaste puntestelsel doeltreffendheid in die herstelkamer sou verbeter in vergelyking met die meer tradisionele tyd-gebaseerde sisteem. Gesonde pasiënte wat kleiner prosedures ondergaan, sal waarskynlik na ’n korter periode ontslaan kan word wat die verpleegpersoneel in staat sal stel om meer aandag aan probleem gevalle te gee. Bespoediging van die pasiëntvloei behoort onnodige vertragings van teatergevalle weens 'n tekort aan beddens in die herstelkamer, te beperk. Die primêre doel van die studie was om te bepaal of die gebruik van die aangepaste puntestelsel as ontslag kriteria in Tygerberg Akademiese Hospitaal, die tydperk wat die pasiënt in die herstelkamer deurbring, verkort. Die herstelkamer verpleegsters het beweer dat die saal personeel ‘n lang tyd gevat het om hulle pasiente in herstelkamer te kom haal. Vervolgens is 'n sekondêre doelwit ingesluit om die tydperk te bepaal vandat die saalpersoneel in kennis gestel word, totdat die pasiënt die herstelkamer verlaat. METODE Goedkeuring is verkry van die Menslike Navorsing en Etiese Komitee van die Gesondheidswetenskap Fakulteit van die Universiteit van Stellenbosch en Tygerberg Akademiese Hospitaal voor die aanvang van die studie. Die studie, asook die doel en moontlike voordele daarvan is vooraf bepsreek met verteenwoordigers van die herstelkamer verpleegpersoneel en skriftelike toestemming is verkry van al die deelnemers wat betrokke sou wees by die data versameling (Addendum B). Oudit vorms (Addendum C), versamelhouers en inligtingsplakkate vir die betrokke personeel is voorberei. Die aanvanklike oudit is in Augustus 2012 oor 'n periode van ongeveer een week uitgevoer. Tydens hierdie oudit is die tradisionele tydgebaseerde sisteem gebruik. Inligting van 327 pasiёnte is versamel. Die oudit vorms is in die versamelbokse geplaas en is daagliks deur die primêre navorser verwyder. Die aangepaste puntestelsel as ontslag kriteria, is in Januarie 2013 in die herstelkamer geïmplementeer. Die verpleegpersoneel het opleiding ontvang waarna die aangepaste puntestelsel vir een maand gebruik is om te verseker dat die personeel vertroud is daarmee. In Februarie 2013, is ‘n tweede oudit oor ‘n tydperk van een week uitgevoer, waartydens inligting van 313 pasiёnte versamel is. RESULTATE Na die implementering van die aangepaste puntestelsel as ontslag kriteria, het die mediane tyd wat pasiënte in die herstelkamer deurbring afgeneem van 1 uur en 25 minute tot 1 uur en 15 minute. Hierdie afname is statities betekenisvol (p-waarde = 0.003) Die mediane tyd vandat die saal in kennis gestel is totdat die pasiënt die herstelkamer verlaat, was 15 minute. GEVOLGTREKKING Die hoof bevinding van die studie is dat die mediane tydperk wat die pasiënte in die herstelkamer deurbring verminder is deur die implementering van die aangepaste puntestelsel as ontslag kriteria in Tygerberg Akademiese Hospitaal.

Malnutrition among hospitalized patients is prevalent and associated with adverse outcomes. At the health care facility for which this quality improvement (QI) initiative was developed, patients were not consistently fed within the nationally recommended 48 hours. The purpose of this project was to facilitate the early initiation of enteral feedings to prevent malnutrition in a vulnerable patient group by development of an evidence-based enteral feeding policy, algorithm, and nursing education module. The find, organize, clarify, understand, select, plan, do, check, and act model provided a systematic approach for development of the project. Validation of the QI initiative was through the use of Likert scale which was completed by 2 nurses and a head dietician. The content validity index average was 1.0 for the QI initiative products (policy, algorithm, educational module). Ten team members completed a summative evaluation of the educational module and presentation using a 7 item, Likert scale. Basic descriptive analyses were employed to analyze the data, revealing broad support for the module and the DNP student's leadership. A recommendation was made to conduct an audit using a formal software program to quantify the number of patients who were not being fed within the time frame of 48 hours. Implementing an evidence-based enteral feeding protocol can be a significant intervention that produces better patient outcomes.The implications for social change in this project relates to improvements within the critical care environment.

Increased levels of stress in the workplace have led the American Psychological Association to predict a looming public health crisis. Critical care nurses (CCNs) are highly exposed to stressors in the workplace, more than other nurses. Tens of billion dollars were reported lost in productive work time yearly due to ill health from depression alone. An important gap remains in understanding the relationships of stressors with the amount of stress. Supported by the biopsychosocial stress theory, the purpose of this study was to determine the relationship between frequencies of perceived stressors (IVs) as a source of perceived levels of stress (DV) or allostasis. The mixed-methods study included an online questionnaire and an e-mail interview of 400 hospital-based CCNs from professional nurses' associations in the United States. The Nursing Stress Scale was used to determine the kinds and frequencies of IVs, while the Psychological Stress Measure was used to assess the DV. Multiple regression analysis assessed the strength and direction of the relationships between IVs and DV. Interviews fell short of the minimum sample size for saturation and were not analyzed. Quantitative findings indicated workload as the most frequently perceived stressor, correlating positively with allostasis (p = .0005). Death and dying, conflict with other nurses, and lack of support for CCNs were also statistically significant (p < .05). Implications to practice and social change include promoting changes in policy with management support to reduce workload, death and dying, conflict with other nurses, and lack of social support for CCNs. Personal behavior changes like relaxation and physical exercises as coping methods may also reduce levels stress.

Compassion fatigue (CF), also known as secondary traumatic stress (STS), impacts critical care nurses (CCN) through exposure to pain, suffering, and loss of those for whom they provide care and results in a reduction of compassion satisfaction (CS). High incidence of CF and turnover (TO) rates at the project site were identified among CCNs. The institution's CCN TO rate was at 81% in comparison to peers in other areas at 29%–35%. The practice-focused question asked whether leadership education on CF might ameliorate CF at the project site. The purpose of the Doctor of Nursing Practice project was to reduce the incidence of CF and TO among CCN through leadership education. Watson's theory of human caring was used as a framework. Two hundred twenty-nine CCNs completed the Professional Quality of Life survey that measures CS, STS, and burnout (BO). Comparison of 28 nursing leaders' pretest scores to posttest scores indicated a statistically significant improvement (z = -4.625, p < .001) and knowledge acquisition. BO and CF taken together explained 86% (adjusted R2 = .86) of the variance in CS (F [2, 227] = 691.33, p < .001). Identifying the nursing units with the highest CF scores and providing CF education to the leadership provides a path to reduce turnover and provide needed support to CCNs, a positive social change.

Delirium is an acute change in cognition accompanied by inattention, which affects up to 88% of adult critical care patients. Delirium causes increased hospital complications, longer lengths of hospital stay, functional disability, cognitive impairment, and increased mortality. The purpose of this evidence-based quality-improvement project was to implement and evaluate a delirium screening process in adult intensive care units at a large medical center. This included education of nurses, implementation of a structured, validated tool, and review of tool use documentation. The implementation of this project was guided by an evidence-based practice model, Disciplined Clinical Inquiry© and Lewin's change theory. Evaluation of this quality-improvement project used audits of the electronic medical record. The audits included the presence and accuracy of delirium screening documentation in the patients' medical records. Results of 3 sequential documentation audits revealed a gradual adoption of this practice change by nurse clinicians. The percentage of charts with missing, incomplete, or inaccurate data decreased from 50% on the first week to 27.9% and 25.0% on the 2nd and 3rd weeks, respectively. These findings were an indication of practice change by validating the requirement for delirium screening on the units. In the first 3 weeks alone, 17 patient audits were positive for delirium, indicating the potential for poor short-term and long-term patient outcomes if not addressed promptly. Implementation of delirium screening ensures the dignity and worth of adult critical care patients by decreasing the poor outcomes associated with the diagnosis, which is an important contribution to positive social change.