Comparison of the Effects of Full Median Sternotomy vs. Mini-Incision on Postoperative Pain in Cardiac Surgery: A Meta-Analysis

ABSTRACT Introduction: It is not yet clear whether cardiac surgery by mini-incision (minimally invasive cardiac surgery [MICS]) is overall less painful than the conventional approach by full sternotomy (FS). A meta-analysis is necessary to investigate polled results on this topic. Methods: PubMed®/MEDLINE, Cochrane CENTRAL, Latin American and Caribbean Health Sciences Literature (or LILACS), and Scientific Electronic Library Online (or SciELO) were searched for all clinical trials, reported until 2022, comparing FS with MICS in coronary artery bypass grafting (CABG), mitral valve surgery (MVS), and aortic valve replacement (AVR), and postoperative pain outcome was analyzed. Main summary measures were the method of standardized mean differences (SMD) with a 95% confidence interval (CI) and P-values (considered statistically significant when < 0.05). Results: In AVR, the general estimate of postoperative pain effect favored MICS (SMD 0.87 [95% CI 0.04 to 1.71], P=0.04). However, in the sensitivity analysis, there was no difference between the groups (SMD 0.70 [95% CI -0.69 to 2.09], P=0.32). For MVS, it was not possible to perform a meta-analysis with the included studies, because they had different methodologies. In CABG, the general estimate of the effect of postoperative pain did not favor any of the approaches (SMD -0.40 [95% CI -1.07 to 0.26], P=0.23), which was confirmed by sensitivity analysis (SMD -0.02 [95% CI -0.71 to 0.67], P=0.95). Conclusion: MICS was not globally less painful than the FS approach. It seems that postoperative pain is more related to the degree of tissue retraction than to the size of the incision.

Coronary perfusion pressure during antegrade cardioplegia in on-pump CABG patients

Abstract Objective: The aim of this study was to investigate whether aortic tension estimated by palpation and cardioplegia infusion line pressure provide results equivalent to those obtained with direct aortic intraluminal pressure measurement. Methods: Sixty consecutive patients who underwent coronary artery bypass graft surgeries with extracorporeal circulation were analyzed. Sanguineous cardioplegic solution in a ratio of 4:1 was administered using a triple lumen antegrade cannula. After crossclamping, cardioplegia was infused and aortic root pressure was recorded by surgeon (A) considering the aortic tension he felt in his fingertips. At the same time, another surgeon (B) recorded his results for the same measurement. Concomitantly, the anesthesiologist recorded intraluminal pressure in the aortic root and the perfusionist recorded delta pressure in cardioplegia infusion line. None of the participants involved in these measurements was allowed to be informed about the values provided by the other examiners. Results: The Bland-Altman test showed that a considerable variation between aortic wall tension was found as measured by palpation and by intraluminal pressure, with a bias of -9.911±18.75% (95% limits of agreement: -46.7 to 26.9). No strong correlation was observed between intraluminal pressure and cardioplegia line pressure (Spearman's r=0.61, 95% confidence interval 0.5-0.7; P<0.0001). Conclusion: These findings reinforce that cardioplegia infusion should be controlled by measuring intraluminal pressure, and that palpation and cardioplegia line pressure are inaccurate methods, the latter should always be used to complement intraluminal measurement to ensure greater safety in handling the cardioplegia circuit.

New quantitative variables to measure postoperative pericardial adhesions: useful tools in experimental research / Novas variáveis quantitativas para avaliação das aderências pericárdicas: ferramentas úteis na pesquisa experimental

PURPOSE: To improve the measurement system, during a research for the prevention of adhesions, we explored the feasibility of introducing three continuous numeric variables to quantify the intensity of pericardial adhesions. METHODS: To validate these three new numeric variables - time spent to dissect the adhesions (Δt), the amount of sharp dissection (ShpD) and the adhesion's collagen area (ACA) - as useful tools in measuring the severity of pericardial adhesions, data from a randomized study on adhesion prevention enrolling twenty-four swine, were analysed. A statistical Spearman's test and regressions models were applied to verify the correlation and the relationship between the results of a standard severity score (SS) and Δt, between SS and ShpD used in adhesiolysis and, also, between SS and ACA. RESULTS: There was a statistically significant correlation between SS and Δt, between SS and ShpD, as well as between SS and ACA, all measured by the Spearman's test (r=0.897, r=0.932, r=0.66; p<0.01, respectively). Through a non-linear regression, an exponential relation of SS with ShpD (R²=0.915) and SS with Δt (R²= 0.917) was found. CONCLUSION: The time spent to dissect the adhesions (Δt) and the amount of sharp dissection (ShpD) are new powerful measurement tools in evaluating outcomes of the methods used to prevent pericardial adhesions.

OBJETIVO: A fim de melhorar a metodologia de mensuração das aderências pericárdicas, avaliamos, durante um estudo de prevenção de aderências pericárdicas, a possibilidade da utilização de três de novas variáveis contínuas e numéricas. MÉTODOS: Para validar estas novas variáveis numéricas - tempo de dissecção (Δt), quantidade de dissecção cruenta (ShpD) e a área de colágeno na aderência (ACA) como instrumentos precisos na quantificação das aderências pericárdicas, foram analisados os dados de um estudo para prevenção de aderências que envolveu 24 porcos. Foram aplicados modelos de regressão e o teste de Spearman para avaliar a força e os tipos correlações entre os resultados do escore padrão de classificação de aderências (SS) e o Δt, entre o SS e o ShpD, e, também, entre o SS e a ACA. RESULTADOS: Foram evidenciadas correlações, estatisticamente significativas, entre o SS e o Δt, entre o SS e o ShpD, também como entre o SS e a ACA avaliadas através do teste de Spearman (r=0,897, r=0,932 , r=0,66; p<0,001, respectivamente). Identificou-se, através de regreção não-linear, uma relação exponencial do SS com o ShpD (R²=0,915) e com o Δt (R²= 0,917). CONCLUSÃO: Este estudo mostrou que o Δt e o ShpD são variáveis poderosas para avaliar os resultados dos métodos utilizados para prevenção das aderências pericárdicas.

Prevenção de aderências pericárdicas pós-operatórias com uso de carboximetilquitosana termoestéril / Prevention of postoperative pericardial adhesions using thermal sterile carboxymethyl chitosan

OBJETIVO: Este trabalho tem como objetivo avaliar alterações físico-químicas da carboximetilquitosana após termoesterilização e sua eficácia na prevenção de aderências pericárdicas pós-esternotomia. MÉTODOS: Após ser submetida a termoesterilização em autoclave, a carboximetilquitosana termoestéril (CMQte) foi submetida a análises físico-químicas. Doze animais foram divididos em dois grupos e submetidos à pericardiotomia e a protocolo de indução de aderências. A seguir, foi aplicada de forma tópica a CMQte ou solução salina. Após 8 semanas, foi realizada esternotomia e avaliação macroscópica do grau de aderências, tempo de dissecção e quantidade do uso de dissecção cruenta e avaliação microscópica. RESULTADOS: As análises físico-químicas não mostraram diferença entre a CMQ e CMQte. A avaliação macroscópica mostrou que a intensidade das aderências foi significantemente menor no grupo CMQte (P=0,007). O tempo de dissecção e o uso de dissecção cruenta também apresentaram reduções significativas (P=0,007, P=0,008; respectivamente). CONCLUSÃO: O método de esterilização empregado não alterou as propriedades físico-químicas da carboximetilquitosana. O uso de biopolímeros de barreira como a CMQte pode reduzir a intensidade das aderências pós-cirúrgicas no pericárdio, diminuindo as complicações da esternotomia em reoperações cardiovasculares.

OBJECTIVE: The aim of this study is to evaluate CMC physical-chemical alterations after thermal sterilization and its efficacy in preventing poststernotomy pericardial adhesions. METHODS: After autoclaving thermal sterilization, thermal sterile Carboxymethyl Chitosan (CMCts) was submitted to physical-chemical analysis. Twelve animals were divided into two groups and underwent pericardiotomy and adhesion induction protocol. Afterward, topic CMCts or saline solution was administered. After 8 weeks, a sternotomy was performed for adhesion score macroscopic evaluation, dissection time and the amount of recalcitrant dissection, and microscopic evaluation. RESULTS: Physical-chemical analysis showed no difference between CMC and CMCts. A macroscopic analysis showed that the intensity of adhesions was significantly lower in the CMCts group (P=0.007). Dissection time and use of recalcitrant dissection also decreased significantly (P=0.007, P=0.008; respectively). Microscopic results indicated a significant reduction in the epicardium collagen area and in the total epicardium area (P=0.05) and (P=0.03). CONCLUSION: The sterilization method did not change Carboxymethyl Chitosan physical-chemical properties. Using barrier bipolymer, such as CMCts, can decrease the intensity of pericardium postoperative adhesions, reducing sternotomy complications in cardiovascular reoperations.

Revascularização híbrida do miocárdio: uma alternativa para reduzir o tempo de perfusão / Hybrid CABG: an alternative for perfusion time decrease

OBJETIVO: Avaliar a possibilidade da redução do tempo de circulação extracorpórea (CEC) e das complicações relacionadas a esta variável na revascularização do miocárdio (RM), utilizando o método híbrido como alternativa. MÉTODOS: Noventa pacientes foram analisados, retrospectivamente, entre março/2000 e agosto/2006. Todos foram revascularizados com três ou mais enxertos e divididos em doisgrupos: híbrido - 45 pacientes que foram operados pela técnica híbrida; total - 45 pacientes operados com CEC. RESULTADOS: No grupo híbrido, o tempo de CEC variou de 20 a 81 minutos e, no grupo total, de 60 a 210 minutos (p<0,001). O tempo de pinçamento aórtico variou de 7 a 70 minutos no primeiro grupo e de 34 a 100 minutos (p<0,001) no segundo grupo. Foi encontrada diferença estatisticamente significativa entre os grupos em relação à incidência de fibrilação atrial e à disfunção renal. CONCLUSÃO: Utilizando-se a técnica híbrida é possível reduzir o tempo de CEC e a incidência de algumas complicações pós-operatórias. Provavelmente, esta redução nas incidências de fibrilação atrial e disfunção renal podem ser explicadas por uma redução na resposta da inflamatória conseqüente a um tempo de CEC menor.

OBJECTIVE: To evaluate the decrease of CPB time and its related complications in CABG using a hybrid alternative method. METHODS: Ninety patients were retrospectively analyzed between March 2000 and August 2006. All were treated with three or more grafts and divided into two groups: Group 1 was the hybrid group - 45 patients who had been operated by the hybrid technique; Group 2 was the total group - 45 patients operated in on-pump. RESULTS: In the hybrid group, the CPB time varied from 20 min. to 81 min. In the total group, the CPB time varied from 60 min. to 210 min. (p<0.001). The aorta cross-clamping time varied in the first group from 7 min. to 70 min. In Group 2, from 34 to 100 min. (p<0.001). A statistically significant difference was found between these two groups in relation to the occurrence of postoperative atrium fibrillation and renal dysfunction. CONCLUSION: Using the hybrid technique it is possible to reduce the CPB time, as well as the occurrence of some postoperative complications. Probably, this decreasing in atrial fibrillation and renal dysfunction incidences could be explained due to a less significant inflammatory activation, which is a consequence of a shorter CPB time.