In recent times, critical care medicine is one of the most rapidly evolving medical specialties. Over last two decades or so, there have been enormous advances in technology, diagnostics, treatment, and our deeper understanding of the pathophysiology of disease processes affecting critically ill patients. Extracorporeal life support (ECLS) is being routinely promoted as a “rescue therapy” rather than supportive treatment for a large number of diseases in day-to-day intensive care practice. The term “extracorporeal” literally means “outside the body”. Extracorporeal therapy (ECT) refers to any mechanical assistance to perform physiologic functions of the body, may be respiratory or cardiac through extracorporeal membrane oxygenation (ECMO) or supporting kidney function through renal replacement therapy (RRT) in different forms. ECMO is used in critically ill patients presenting as acute cardiac and/or pulmonary dysfunctions, who are at high risk of developing acute kidney injury and fluid overload. RRT is commonly used in ICU to provide renal replacement, electrolyte, and fluid management. Beyond these routine indications of ECT, the therapies are further extending their roles into toxicology and sepsis.
The use of RRT and ECMO is no longer limited to the remit of nephrologists and cardiac surgeons, or anesthetists, respectively. They have become a routine therapy in varying clinical conditions in intensive care unit (ICU) on daily basis. The nephrologists or dialysis technicians are not expected to leave their dialysis units and manage ICU patients on bedside RRT. So, an in-depth knowledge of RRT—its indications, contraindications, how and when to begin, troubleshooting, and recent applications in non-renal conditions like poisonings, sepsis, etc.—is mandatory for a hardcore intensivist. Similarly, ECMO is being routinely employed for noncardiac indications in ICU patients, including acute respiratory distress syndrome (ARDS), for extracorporeal carbon dioxide removal (ECCO2R) and for cardiac support in poisonings like in aluminum phosphide (Celphos). So, ECMO has come out of the cardiac surgeon's domain and entered into the intensivists’ arena. This too mandates the accustomization of critical care physician with the practical aspects of ECMO, its applications, and the complications. The main incentive to launch this book dedicated to ECT is the sense of crisis acknowledged by the society regarding the current status of RRT and ECMO in 2Indian ICUs. The aim of this book is to provide concise and pragmatic practical guidelines to clinicians managing patients on ECT in varying clinical conditions at the bedside in ICU.
To broadly assess the knowledge and practices of ECT among intensivists in Indian ICUs, we conducted an online survey including questions on types of ICUs and the practices of RRT and ECMO therein. A total of 320 intensivists responded to the survey through an online portal. According to the survey, only 20% of participating Indian ICUs were closed and 83% of open ICUs are managed by a full-timer intensivist. 94% of participating ICUs have bedside RRT facility available. RRT in 50% ICUs is still managed by the nephrologist, while in only 28% ICUs, RRT is intensivists’ domain. Around one-third of ICUs do not have continuous renal replacement therapy (CRRT) facility. Overall there was no major difference in most common indications for RRT in different ICUs across the country, metabolic acidosis being the most common indication for starting RRT in ICU, followed by rising creatinine and hyperkalemia (64%, 32%, 30%, respectively). The intensivists across the ICUs in the country did not have differences in initiating triggers for commencing RRT. Commonly used triggers were early septic shock with acute kidney injury by 43% intensivists and early Kidney Disease Improving Global Outcomes (KDIGO) stage 3 by 31%. Looking at the nonconventional uses of ECT, 44% of responders had never used RRT for poisonings and only 21% of intensivists were practicing ECMO for resuscitation (eCPR). One-fourth of intensivists are either not modifying or sometimes modifying drug doses for patients undergoing ECT.
The survey highlighted that only 9% Indian ICUs are in public domain, against 50% being in corporate sector and 41% being private setups and there was a statistically significant difference in ICU beds in different sectors (p = 0.000). Availability of ECMO was also significantly different according to the type of setup (p < 0.05). More than half of public sector and private setups do not have ECMO facility as compared to 74% corporate settings having ECMO. There was also a significant difference in intensivists’ preference of RRT modality in hemodynamically unstable patients (p = 0.007). 63% of intensivists from corporate setups preferred CRRT for such patients while only 55% of those working in public sector ICUs and 40% in private setups used CRRT. This might be because of limited availability of resources: 80% of corporate setups and 66% of public and private setups had CRRT facility, but this difference was not statistically significant (p = 0.023). Financial consideration was another major reason while deciding the choice of RRT. 54% intensivists considered high cost as sole reason for not considering CRRT. A major difference in practice among public and private/corporate sector intensivists was the preferred dialysis access (p = 0.000). Femoral access was preferred by public sector (41%) while corporate and private sector physicians (81%, 71%) preferred double-lumen jugular catheters. A significant difference was also observed in use of RRT for poisonings. This indication was used for RRT mostly by corporate sector (40%) while less commonly used by public (24%) or private sector (23%) (p = 0.005). There was a significant difference in intensivist being ECMO team leader in corporate setups (61%) while in public setups (38%) and 54% in private setups (p = 0.017).
Of the total Indian ICUs, 66% have been running teaching programs. On comparison of teaching versus nonteaching ICU, there was a significant difference in availability of both extracorporeal therapies (RRT and ECMO) in teaching versus nonteaching institutes. Only 37% 3of nonteaching institutes had ECMO facility as compared to 72% in teaching hospitals (p = 0.000). 54% of nonteaching ICUs had CRRT facility versus 82% of teaching institutes (p = 0.000). When ECT practices were compared, very few nonsignificant differences were observed.
Keeping in mind the results of survey, the practical aspects of ECT have been vastly covered in the book. The book is divided into two sections: Section 1 including 23 chapters widely covering theoretical and practical management of RRT including acute kidney injury (AKI) epidemiology, setting up of RRT in ICU, different types of RRT available, modality preference for specific ICU patients, how and when to initiate, prescription while starting CRRT, troubleshooting, weaning from RRT, and managing nutrition. Altering the doses of drugs during RRT should be a routine that needs to be inculcated into day-to-day practice. To practically help the intensivists, we have included a separate chapter on drug dosing during RRT. Recent uses of RRT like hemoperfusion in poisonings, therapeutic apheresis, and ECT for sepsis have been included as separate chapters in the book. Section 2 covers ECMO with 24 chapters including physiology of ECMO, indications and contraindications, hardware, cannulation and priming of circuit, how to initiate, anticoagulation, monitoring, sedation, ventilation during ECMO, weaning and complications of ECMO including ECMO sepsis. It also includes unconventional topics like ECMO for poisonings, cardiac issues on ECMO, nutrition during ECMO, and ECMO during cardiopulmonary resuscitation. Another technical aspect of patients on ECMO is how to initiate CRRT during ECMO. This has been included as a separate chapter. Both the sections have separate chapters focusing on pediatric differences in RRT and ECMO. At the end of each section, multiple-choice questions have been provided for the readers to self-assess their overall knowledge of the subject.
The role of ECT in the ICU is primarily to support specific organ dysfunction with multiorgan failure. The strategies to employ it are dynamic and evolving. The ultimate goal of this book is to further promote and practically help the critical care physicians handling bedside ECT in ICUs in their day-to-day management of sick patients requiring specific therapy and be a handy ready reckoner in times of trouble for them. The book will be a great help for critical care students, freshers joining ICUs, and can even at times be a troubleshooter for senior intensivists. It will provide insight into the ECT for general physicians, dialysis technicians, cardiac anesthetists, and perfusionists handling dialysis or ECMO machines. The society also wishes to promote research into AKI, RRT, and ECMO in critically ill patients, which is as of now lacking in Indian ICUs. A national registry database capturing the detailed information of ICU patients requiring RRT and ECMO can be the way forward to look into Indian ICU practices and aim for quality improvement. We sincerely hope that the book serves its purpose and is read by the intensivists not only in India but across the globe.