Quality Control of Inhalation Therapy

RESPIRATORY THERAPY Quality Control of Inhalation Therapy The Results of Therapy. with and without Control. and Methods of Developing Such Control. in a Community Hospital Roman L. Yanda, M.D., F.G.G.P.·

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Deficiencies in quality of thenpy in mnltiple areas, were demonstnted dnring a Iongterm snrveillaDce program. Both tnining in and present methods of clinical monitoring were inadequate. One-tbird of patients were significantly under/over ventilated, pressures were used in a rote manner and respintory rate control was lacking. Feedback to the physician was missing. These problems were correctable, once identified; eumple: rednction in incidence of tachypnea 21 to 8 percent and bypoventila-

tion to 14 percent. Correction required routine respiratory measurements, intensive inservke education, appropriate staft clumges and Improved physician 1iaIsoD. Additionally, patients' actual ventilatory requirements most be establisbed, in which physicians must become more

The question of "what does inhalation therapy do?" is under continuing and intensive study,!'" primarily conducted under close physician supervision. How inhalation therapy is administered is less clearly defined. To date, no definitive studies have

tions for therapy; (6) multiple levels of informed supervision, technical, administrative, and medical; (7) available, reliable and objective means of evaluating results of therapy; and (8) overall regulation of the basic activities by various public health agencies. While such criteria are probably in existence at major medical centers, completely or in part, they are still absent from the general community hospital. A pilot surveillance program designed to meet some of the needs, elaborated above, has been evolving at Sherman Oaks Community Hospital. This inhalation therapy department was chosen because of its uniformly high standards of training and experience, coupled with staff flexibility. Thus, the results presented are from an above average situation. Intermittent positive pressure breathing ( IPPB ) treatments occupied approximately 70 percent of the department's effort and is amenable to measurement. Thus, initially the study was restricted to surveillance of this activity as an index of total departmental effectiveness.

For editorial comment, see page 1

been published in the medical literature. The present empiric methods of quality control ie, "spot checking" involve the presence of an observer. The stimulus of this observer removes the therapy from the category of usual performance, since this involves only the technician and the patient. Consequently, the question of just what happens when routine inhalation therapy is ordered remains unanswered. Obviously, in this field, the manner in which the therapy is administered may have as much influence on results of therapy as any of the possible physiologic mechanisms of action. Thus, it is essential to be assured of the uniform quality of therapy administered before searching for its physiologic mechanisms of action. The exponential growth of this field has outstripped the development of the usual checks and balances in medical therapy. The bulwarks of quality control, present in other fields of therapy are deficient or missing. These are: (1) a uniform level of prerequisites for admission to training in this field; (2) uniform standards of training ; (3) an adequate pool of trained talent fulfilling the stipulated job requirements; (4) standard operating procedures of high quality; (5) well developed indica·Medical Director, Bespiratory Service, Shennan Oaks Community Hospital, and Associate Clinical Professor of Medicine, University of Southern California, Los Angeles. Manuscript received December 5; revision accepted January 23. Reprint requests: Dr. Yanda, 15243 Van Owen, Van Nuys, California 9140S

CHEST, 66: 1, JULY, 1974

directly involved. FinaDy, nnIess the quality of intermittent positive pressure breathing (lPPB) provided is uniformly maiDtained, there will be no way that response to thenpy can be ac:cuntely assessed.

METIIOD

Each inhalation technician was required to observe, record, and report specific representative measurements from each treatment administered. These measurements were: (1) tidal volume, (2) minute ventilation, (3) respiratory rate, and (4) pressures used to deliver the therapy. Initially technicians were issued monitoring equipment (Wright and Draeger Respirometers) that was standard in the field. After six months of surveillance, maintenance and calibration problems required the substitution of less expensive monitoring equipment (Hudson Venticomp) that was equally accurate and more reliable. All were calibrated with standard watersealed spirometers. Technical details of the initial inhalation therapy aspects were published in a professional society joumal.ll The methods of statistical surveillance were used to monitor total departmental effectiveness. Data from all cases treated were analyzed for the patterns of distribution at

QUALITY CONTROL OF INHALATION THERAPY 61

technician's lack of awareness of the ventilation that he was administering. In I ( b ), however, higher respiratory rates apparently are uniformly associated with low tidal volumes; a relationship that previously had not been appreciated. Low respiratory rates are also associated with low volumes. The degree of reliable inference that can be drawn from rate is very close to zero. There is no predictive relationship between pressure and volume; tidal volumes of less than 500 ml are found in both extremes of pressures used. Replotting similar data from activities six months later produced the same random distribution, with one minor change: there were far fewer instances of tidal volumes under 500 ml no matter the correlation of rate or pressure. A response to eliminate low tidal volumes, without the necessity of measurement, was proposed. The plan was to increase pressures used in all treatments by 5 em. For validation, measurements were taken as illustrated in Figure 2, tidal volumes at x em vs tidal volumes at x + 5 em of pressure. Inspection reveals that only those tidal volumes that required no supplementation are increased significantly. Smaller volumes, presumably due to decreased compliance showed little change. In essence without some knowledge of volume, the technician is unable to intelligently modify the treatment situation. Even technicians with extensive training and experience were unaware of these facts until confronted by repeated measurements of the situation.

regular intervals. The study was designed to ensure anonymity and avoid pressures that might alter the technician's behavior, particularly in record keeping. Initially, data were collected in a specific manner so as to sample the usual performance, in the absence of feedback. Subsequent review (of this baseline) disclosed that the majority of technicians were unaware of the practical significance of the measurements. Once baseline data were collected and analyzed, the full results and implications of these findings were repeatedly reviewed with the staff. Deviations in performance from optimum were identified and corrective measures were taken. Surveillance, monitoring, and feedback continued with formal analysis at six monthly intervals. The program was designed to provide information with which to answer the following questions: 1. Are present methods of clinical monitoring adequate? 2. Are community levels of inhalation practice adequate? 3. If major deficiencies are present, what are they specifically? 4. Are these deficiencies (if present) remediable and how? 5. What further changes are needed to improve administration of services? REsULTS

Clinical Monitoring

Tidal volume vs pressure, and tidal volume vs respiratory rate were plotted to determine if trained and experienced technicians could assess the adequacy of ventilation on the basis of clinically available data (Fig la, b). The purpose was to determine the relationship between ventilation and objective data, available at each treatment. If the technician is to gauge ventilation without equipment, he must perforce relate it to some available variable which he can identify and quantify. Figure I displays a totally random distribution of tidal volume when correlated with rate or pressure. From the study, pressure and rate have no obvious predictive value in identifying vagaries of volume. These and other data, to follow, illustrate in the baseline period, the

Statistical Surveillance

The accumulated measurements of each parameter were then plotted to determine their pattern of distribution. An adequate sample of a continuously

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62 ROMAN L YANDA

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variable biologic measurement should fall into a typical gaussian distribution. Significant deviation from such pattern would indicate the existence of some nonvariable influence, which could then be identified. For easier comparison the data from the two periods were plotted in a cumulative manner. This discrete probability distribution curves- should give a close approximation of a rectangular hyperbola if the data are entirely random. Additionally, this display allows the rapid estimation of the median and quartiles. Thus, superimposition of the six-month line on the background line would indicate no change. Conversely, deviation of the two lines would indicate a basic change in the pattern of distribution. Finally, a change in the shape of the "granulated distribution curve" from the hyperbolic shape would

imply the presence of another factor in the distribution; In Figure 3, the respiration rate has a gaussian distribution, with a mode at 13 (in the baseline study). Since there was an average of 18 measurements per patient, it is obvious that excessively rapid respiration rates occurred on multiple occasions. Presumably, the technicians were not keyed to react to, or even recognize its significance. Previous inservice education had stressed the advantages of slow breathing rates. The technician's behavior obviously was not influenced by this didactic approach. After six months of surveillance, feedback, and intensified training, fresh data, plotted as a cumulative curve (Fig 3 b) showed that the incidence of tachypnea was reduced significantly to eight percent. This is about one episode per patient, presumably his first treatment. In the interval, the technicians had learned to react to a rapid rate and were taking more appropriate action. Figure 4 shows a gaussian distribution with the mean at 10 liters/minute originally and 12 subsequently (996 observations initially and 900 at six months). A search of the literature for normal limits of ventilation in respiratory disease was nonproductive. Data on ventilatory limits for the normal person were found.6-8 Radford" derived his nomogram from data on patients with poliomyelitis and on medical students. He specifies its applicability only to persons with a normal deadspace. Since the results of this study showed a much higher ventilation and presumably mainly involved patients with an abnormal deadspace, we felt obliged to check further. Collecting data on patients studied in the hospital's pulmonary laboratory, under near basal conditions, we found in 400 assorted patients that the average minute ventilation was 5.2 ± or 0.6 liters/min/ M", with an average oxygen uptake of 168 -+- or 33 ml/min/M". Since the patients in the present study were neither in remission nor in basal state, we chose to continue using our previously IOO~

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QUALITY CONTROL OF INHALATION THERAPY 63

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established empiric level of "normal," which was 917 liters/min (this is only slightly higher than the range observed on patients in the pulmonary laboratory). No data from patients on continuous IPPB or patients on volume ventilators were used in this study. That group was managed with frequent arterial blood gas analysis. Such feedback is presently impractical for the average respiratory patient on IPPB. Initially, hypoventilation was present in 27 percent (206 of 996). At the end of six months the incidence was reduced to 14 percent (Figure 4b). The plot of the two cumulative curves illustrates the difference. Hyperventilation, initially, was a minor problem (10 percent), presumably because of previous inservice training stressing the undesirable effects of excessive ventilation. However, when the focus of attention was switched to preventing hypoventilation, there was an almost equal increase in hyperventilation. Attention to the excessive ventilation was reinstated. A major problem is determination of optimal limits of ventilation in the ill patient. Obviously, this will have to be influenced by the rationale or indications for therapy. Thus, physician involvement in setting broad limits for his patient is desirable. Rote use of a set volume is as bad as rote use of pressure. Unfortunately, facilities for routine measurement of ratio of deadspace ventilation to total ventilation VO/VT) were not available. This would be an ideal way to determine ventilatory limits. Figure 5 shows a distribution that is not random (1,021 instances initially, 887 subsequently). Three pressures, 20, 15, and 18 em accounted for 71 percent of all settings used. The dotted line on the graph indicates actual distribution at one-half scale before averaging techniques were used. Such a rigid automatic pattern of use in spite of abundant evidence of hypoventilation, tachypnea, and hyperventilation, must be the result of previous training. A 64 ROMAN L YANDA

year later, similar results were found at two other community hospitals recently instituting this same statistical surveillance technique. Thus, even with experienced technicians, the clinical circumstances had almost no effect on the customary behavior, although the primary task was to maintain ventilation appropriately in patients. The implication, since we draw our technicians from the same pool of talent as others, is that their training, in this respect, is much too rigid. Only 2.6 percent of pressures recorded initially exceeded 20 em. There was no basis for this limitation in the technicians' experience at this hospital. With six months of further training and feedback, selection of pressure showed a much wider, presumably more appropriate selection. Twenty-one percent were now in excess of 20 em and six pressure settings comprised 70 percent of those selected. The two cumulative curves in Figures 5b show this wide divergence. Previously the usual method was to only record data in the patient's chart. Since, due to the work pressure, the technician makes only one trip to the chart area after administering the treatment (to record date, time, results, etc) this meant he was "flying blind." With this card, which he carries with him, he now has a ready reference to past performance at the time he gives the treatment (Fig 6). Additionally, he can show the data to the patients' physician whenever he encounters him. Thus, data are recorded on the chart and on the card, permitting much more routine quality control. DISCUSSION

Data from this pilot study provide substantial answers to the questions initially proposed. These are: Answer 1. Present methods of clinical monitoring (of ventilation) during inhalation therapy are inadequate. Only direct measurements will rectify the situation. The nature of these direct measurements CHEST, 66: 1, JULY, 1974

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will vary from situation to situation, and likely from ,hospital to hospital. The simplest method is to routinely measure ventilation, rate, and pressure. Answer 2. Currentcommunity standards of ventilatory practice are obviously inadequate in at least the following respects: (a) Technicians act as if their clinical assessment is adequate and make no effort to obtain additional information relating to the treatment given. Most physicians are similarly unaware of the limitations of clinical judgment on the part of these technicians; (b) technicians ex-

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hibited a ritualistic approach to therapy so that adjustments to the variations in the clinical situation were absent; (c) there was general avoidance of pressures above 20 em, even when clinically indicated; (d) inadequacies of ventilation and other performance problems were not reported to the prescribing physician. Presumably, if inadequacies are not identified, then no report need be made. Answer 3. Major deficiencies were present and were specifically: (1) excessive tachypnea in 21 percent; (2) a high incidence of hypoventilation in 24DATE

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QUALITY CONTROL OF INHALATION THERAPY 65

27 percent; (3) hyperventilation in 7-10 percent; (4) rote use of pressure; and (5) absence of useful feedback data to the physician. Answer 4. Deficiencies were remediable by major change in course content and character of the inservice training program. Workshops, demonstration and study groups were the principal methods used to effect change. Additionally, equipment for measuring patient ventilation had to be carr.ed by each technician while on duty. Consequently, equipment had to be portable, reliable, durable and less expensive. This necessitated a change from the Draeger and Wright respirometers to the disposable Venticomp." For those rare inhalation technicians who are unable or unwilling to modify their almost Pavlovian response to the therapy situation, employment was terminated. Younger replacements are more easily trained in the new techniques of observing, recording and reporting respiratory measurements at each treatment. The results of this study were and are being thoroughly discussed with the technical staff. Adequate opportunity is provided to try various measures and modifications of the previous routine inhalation behavior. One such excellent modification (originating with the assistant supervisor) was to obscure all of the numbers on the dials of the IPPB equipment except for the pressure manometer. The effect was to reinforce technicians' reliance on clinical assessment and measurement at each treatment. This modification was uniformly adopted and further data collection is in progress. With the exception of hyperventilation problems, therapy appears to be more adequate now. Answer 5. Additional changes recommended to improve the quality of therapy include the following: (a) There should be assumption of a need for the prescribing physician to detail indications for therapy ordered, ie, the goal of therapy, and the ventilatory limits that he feels would be appropriate. The feedback presently developing will then enable him to adjust therapy appropriately and to decide when the results desired have been attained. (b) There should be availability of patient data to the treating therapist so that he may get a perspective as to previous methods of therapy. CONCLUSION

A method of statistical surveillance was used to pinpoint significant deficiencies in the administration of inhalation therapy. This was accomplished without specifically threatening any individual technician (with the exception of those who refused to measure, record, and report data), thus ensuring their full cooperation. The deficiencies in perfor·The Venticomp measures tidal volumes and V in the lower ranges (hypoventilation) with precision. It is relatively inaccurate in measuring tidal volume above 1,500 ml, but this was not felt to be an operationally significant drawback.

66 ROMAN L. YANDA

mance were directly attributable to inadequacies in training and subsequent supervision, which were not previously apparent. Providing technicians with feedback so that they can modify their activities has resulted in a ready acceptance of more stringent patterns of care. The concomitant improvement in quality of care is documented by the changes in distribution of respiratory measurements observed. At this point increased physician involvement in defining the goals of therapy becomes practical and feasible. This study was possible, in this hospital, because of facilities for intensive inservice training and equipment to monitor patient ventilation. The critical factor was the realization by the majority of the staff that problems existed, without apparent solution, in the framework of current practice. Such a combination of factors is a rarity in hospitals in this geographic area. It is quite likely to be true of the rest of the nation. Consequently, deficiencies in administration of inhalation therapy as detailed in this study are likely to be widespread in hospitals in which departments lack the facilities to measure performance objectively, without data on file. The medical profession must initiate requests for objective evidence of adequate performance. When the prescribing physician has· measurements of results of therapy, he can then begin to be assured of the quality of therapy which he intended. Once this quality of care is assured, the results can be properly evaluated. Does IPPB actually produce the results for which it is prescribed? Such studies with quality control of the product are long overdue. ACKNOWLEDGMENTS: The full cooperation of the following, during the period of surveillance, is gratefully acknowledged: supervision of data collection by J. Pister; continuous data analysis by M. S. Yanda; and provision of facilities by the Administration, and Inhalation Therapy Department of Sherman Oaks Community Hospital. REFERENCES

1 Noehren TH: Is positive pressure breathing overrated? Chest 57:507-509,1970 2 Baxter WD, Levine RS: An evaluation of intermittent positive pressure breathing in the prevention of postoperative pulmonary complications. Arch Surg 98:795-798, 1969 3 Birnbaum ML, Cree EM, Rasmussen H, et al: Effects of intermittent positive pressure breathing on emphysematous patients. Am J Med 41:552-561, 1966 4 Sheldon GP: Pressure breathing in chronic obstructive lung disease. Medicine (Baltimore) 42:197-227, 1963 5 Yanda RL: Quality control of intermittent positive pressure breathing; a baseline study. Respiratory Care 18:33-39, 1973 Sa Scientific Tables: Documenta Geigy (Diem K, ed). Ardsley, N.Y., Geigy Phannaceutical, 1962, pp 147-152 6 Radford Jr EP: Ventilation standards for use in artificial ventilation. J'Appl PhysioI7:541-460, 1955 7 Handbook of Respiration (Dittmer DS, Grebe RM, eds). Philadelphia, WB Saunders Co, 1958, p 143 8 Respiration and Circulation (Altman PL, Dittmer DS, eds ). Federation of American Society for Experimental Biology, 1971, p 42

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