Mark R. Tonelli

Sputum induction as a research tool for sampling the airways of subjects with cystic fibrosis

BACKGROUND Sputum induction (SI) has proved to be a reliable non-invasive tool for sampling inflammatory airway contents in asthma, with distinct advantages over collection of expectorated sputum (ES) and bronchoalveolar lavage (BAL). A study was undertaken to evaluate the safety of SI and to assess if it might be an equally valuable outcome tool in patients with cystic fibrosis (CF). METHODS The safety of the procedure was examined and sample volume, cell counts, cytokine concentrations, and bacterial culture results obtained by SI, spontaneous ES, and fibreoptic bronchoscopy were compared in 10 adults with CF. RESULTS SI was well tolerated and was preferred to BAL by all subjects. The mean (SE) sample volume obtained by SI was significantly greater than ES (6.74 (1.46) ml v 1.85 (0.33) ml, p = 0.005). There was no significant difference in the number of cells per ml of sample collected. There was a difference in the mean (SD) percentage of non-epithelial, non-squamous cells collected (67 (28)%, 86 (21)%, and 99 (1)% for ES, SI, and BAL, respectively). These percentage counts were different between ES and both SI and BAL (p=0.03 and p=0.006, respectively). Cell differential counts (excluding squamous cells) from all collection methods were similar (mean (SD) 84 (9)%, 87 (7)%, and 88 (11)% polymorphonuclear cells for ES, SI, and BAL, respectively). The concentrations of interleukin (IL)-8 and tumour necrosis factor (TNF)-α were the same in all three samples when corrected for dilution using urea concentration. The test specific detection rate for recovery of bacteriological pathogens was 79% for SI, 76% for ES, and 73% for BAL. CONCLUSION SI offers safety advantages over BAL and may be a more representative airway outcome measurement in patients with CF.

The philosophical limits of evidence-based medicine

Evidence-based medicine (EBM) has already had a profound effect on both medical education and clinical practice. The benefits of EBM, which defines the value of medical interventions in terms of empirical evidence from clinical trials, are enormous and well described. Not clearly acknowledged, however, are the limits of EBM. An intrinsic gap exists between clinical research and clinical practice. Failure to recognize and account for this gap may lead to unintended and untoward consequences. Under the current understanding of EBM, the individuality of patients tends to be devalued, the focus of clinical practice is subtly shifted away from the care of individuals toward the care of populations, and the complex nature of sound clinical judgment is not fully appreciated. Despite its promise, EBM currently fails to provide an adequate account of optimal medical practice. A broader understanding of medical knowledge and reasoning is necessary.

Why alternative medicine cannot be evidence-based.

The concept of evidence-based medicine (EBM) has been widely adopted by orthodox Western medicine. Proponents of EBM have argued that complementary and alternative medicine (CAM) modalities ought to be subjected to rigorous, controlled clinical trials in order to assess their efficacy. However, this does not represent a scientific necessity, but rather is a philosophical demand: promoters of EBM seek to establish their particular epistemology as the primary arbiter of all medical knowledge. This claim is problematic. The methods for obtaining knowledge in a healing art must be coherent with that arts underlying understanding and theory of illness. Thus, the method of EBM and the knowledge gained from population-based studies may not be the best way to assess certain CAM practices, which view illness and healing within the context of a particular individual only. In addition, many alternative approaches center on the notion of non-measurable but perceptible aspects of illness and health (e.g., Qi) that preclude study within the current framework of controlled clinical trials. Still, the methods of developing knowledge within CAM currently have limitations and are subject to bias and varied interpretation. CAM must develop and defend a rational and coherent method for assessing causality and efficacy, though not necessarily one based on the results of controlled clinical trials. Orthodox medicine should consider abandoning demands that CAM become evidence-based, at least as “evidence” is currently narrowly defined, but insist instead upon a more complete and coherent description and defense of the alternative epistemic methods and tools of these disciplines.

In defense of expert opinion

Evidence-based medicine, centered on the incorporation of evidence from clinical trials and systematic reviews into the teaching and practice of clinical medicine, explicitly attempts to supplant expert opinion, which is viewed as an antiquated and unreliable form of medical authority. The epistemology of evidence-based medicine categorizes expert opinion as the lowest form of medical evidence, superseded even by methodologically flawed clinical research. When derived from direct clinical experience, however, expert opinion represents an alternative form of medical knowledge, one that may be complementary to empirical evidence. Input from clinical experts is vital to informing the context of clinical research and an appeal to alternate forms of medical knowledge, including expert opinion, is necessary to overcome the intrinsic gap between clinical research and the care of individual patients. Even when the quality and quantity of empirical medical evidence are ideal, expert opinion will remain an integral part of the multifaceted knowledge required for the optimal practice of clinical medicine.

Meeting Physicians’ Responsibilities in Providing End-of-Life Care

Despite many clinical examples of exemplary end-of-life care, a number of studies highlight significant shortcomings in the quality of end-of-life care that the majority of patients receive. In part, this stems from inconsistencies in training and supporting clinicians in delivering end-of-life care. This review describes the responsibilities of pulmonary and critical care physicians in providing end-of-life care to patients and their families. While many responsibilities are common to all physicians who care for patients with life-limiting illness, some issues are particularly relevant to pulmonary and critical care physicians. These issues include prognostication and decision making about goals of care, challenges and approaches to communicating with patients and their family, the role of interdisciplinary collaboration, principles and practice of withholding and withdrawing life-sustaining measures, and cultural competency in end-of-life care.

An Official Multi-Society Statement: The Role of Clinical Research Results in the Practice of Critical Care Medicine

BACKGROUND While the results of clinical research are clearly valuable in the care of critically ill patients, the limitations of such information and the role of other forms of medical knowledge for clinical decision making have not been carefully examined. METHODS The leadership of three large professional societies representing critical care practitioners convened a diverse group representing a wide variety of views regarding the role of clinical research results in clinical practice to develop a document to serve as a basis for agreement and a framework for ongoing discussion. RESULTS Consensus was reached on several issues. While the results of rigorous clinical research are important in arriving at the best course of action for an individual critically ill patient, other forms of medical knowledge, including clinical experience and pathophysiologic reasoning, remain essential. No single source of knowledge is sufficient to guide clinical decisions, nor does one kind of knowledge always take precedence over others. Clinicians will find clinical research compelling for a variety of reasons that go beyond study design. While clinical practice guidelines and protocols based upon clinical research may improve care and decrease variability in practice, clinicians must be able to understand and articulate the rationale as to why a particular protocol or guideline is used or why an alternative approach is taken. Making this clinical reasoning explicit is necessary to understand practice variability. CONCLUSIONS Understanding the strengths and weaknesses of different kinds of medical knowledge for clinical decision making and factors beyond study design that make clinical research compelling to clinicians can provide a framework for understanding the role of clinical research in practice.

The challenge of evidence in clinical medicine

The primary goal of evidence-based medicine (EBM) has been to change the way clinicians make decisions. But EBM has inappropriately privileged the results of clinical research for medical decision making and has undermined the importance of other kinds of medical knowledge, pathophysiologic understanding and clinical experience, to clinical practice. Here, the specific advantages and limitations of each kind of medical knowledge are examined. No particular kind of medical knowledge is necessarily more compelling than the others when it comes to making specific patient care decisions. Several cases where medical knowledge is conflicting are examined to demonstrate the weighting and negotiation necessary for sound clinical judgement. Expert clinicians must utilize a variety of reasons and methods of reasoning in arriving at the best clinical decision or recommendation for an individual patient. The process can be formalized and made explicit, but it cannot be narrowed, simplified and focused only on the results of clinical research.

Fentanyl-Induced Chest Wall Rigidity

Fentanyl and other opiates used in procedural sedation and analgesia are associated with several well-known complications. We report the case of a man who developed the uncommon complication of chest wall rigidity and ineffective spontaneous ventilation following the administration of fentanyl during an elective bronchoscopy. His ventilation was assisted and the condition was reversed with naloxone. Although this complication is better described in pediatric patients and with anesthetic doses, chest wall rigidity can occur with analgesic doses of fentanyl and related compounds. Management includes ventilatory support and reversal with either naloxone or a short-acting neuromuscular blocking agent. This reaction does not appear to be a contraindication to future use of fentanyl or related compounds. Chest wall rigidity causing respiratory compromise should be readily recognized and treated by bronchoscopists.

Compromised Autonomy and the Seriously Ill Patient

Respect for patient autonomy has become the preeminent principle of medical ethics, to the point that tools have been developed, such as instructive directives, in an attempt to preserve a semblance of autonomy even when it has become clearly and irretrievably lost. Much of the practice around the respect for autonomy, however, mistakenly supposes that the capacity for autonomous choice is an all-or-nothing proposition. But seriously ill patients may retain some ability to participate in discussions of medical care yet have their autonomy profoundly compromised by physical duress, cognitive dysfunction, or delirium. The choices of individuals with compromised autonomy do not carry the same moral weight as those of the fully autonomous. Clinicians, therefore, cannot rely on such choices for guiding medical decisions and are obligated to evaluate them more fully before acting. We argue that clinicians should compare the choices of individuals with compromised autonomy to a medical assessment of the patients best interest. When the patients choice and the best-interests assessment are discordant, acting in the patients best interest may, at times, rightly override the requests of the patient. Such an approach, under a tightly constrained set of circumstances, would permit both the provision and the withholding of medical interventions despite patient requests to the contrary.

Evidence-Free Medicine: Forgoing Evidence in Clinical Decision Making

Despite being the central concept to evidence-based medicine (EBM), evidence remains an elusive and controversial notion. Ongoing debates regarding evidence primarily serve to confuse and obfuscate. Examination of the nature of medical decision making without any appeal to evidence reveals a more complete understanding of the optimal practice of clinical medicine. An “evidence-free medicine” allows for the incorporation of a variety of facts and warrants, reasons and reasoning, into clinical decisions. The relative weighting of potentially conflicting warrants for a medical decision comprises the critical process of clinical judgment. Forgoing evidence allows clinical medicine to once again be a personal and prudential undertaking, arising from and focused on the individual patient.