uses and misuses of oxygen in hospitalized patients

Uses and Misuses of Oxygen in Hospitalized Patients DAVID SMALL, M.D., AALO DUHA, BRAM WIESKOPF, ESTHER DAJCZMAN, N.,M.sc.A., DENNY LAPORTA, M.D., HARVEY KREISMAN, M.D., NORMAN WOLKOVE, M.D., HAROLD FRANK, M.D., Montreal, Canada

PURPOSE: To document the use/misuse of oxygen therapy as compared with antibiotics in internal medicine inpatients. To determine whether the same care was being taken in the prescription and administration of both forms of therapy.

PATIENTS: Ninety-six eligible patients at a university teaching hospital were entered into a study examinkg the use of oxygen. They were compared with 60 patients for whom antibiotics were prescribed.

MATRRrALANDMETHOD&Three hundredthirty consecutive newly admitted patients were screened for the presence of either (1) oxygen apparatus at the bedside, (2) physician orders for oxygen, or (3) oxygen orders noted in nursing hardex. Those meeting one of these three criteria were observed on up to four occasions over 48 hours following study entry. Similarly, patients were screened for medical orders or nursing medication lcardex notation for antibiotics and were also observed for proper prescription and administration of medication. Proce- dural errors, determined by hardex audit and direct patient observation, were compared for the individuals with specific oxygen orders and those receiving antibiotics.

RESULTS: Oxygen delivery apparatus was found in the room in 17 of 96 patients without it ever having been ordered by the physician or noted in the nursing hardex. In 27 of 96 patients, oxygen was noted in the nursing hardex and administered to patients without a physician order. There were no cases of antibiotic therapy without a physician order. Observations of 47 patients with specific orders for oxygen revealed the following errors: (1) physician order incor-

From the Division of Pulmonary Diseases, Department of Medicine, Sir Mortimer B. Davis-Jewish General Hospital, McGill University, Montreal, Canada.

This work was supported in part by the Dr. Israel Winkler Family Fund for Pulmonary Research, and the McGill National Awards Program Scholarship.

Requests for reprints should be addressed to David Small, M.D., Sir Mortimer B. Davis-Jewish General Hospital, Department of Medicine, Division of Pulmonary Diseases, 3755 Cote St. Catherine Road, Montre- al, Quebec H3T lE2, Canada.

Manuscript submitted September 12, 1991, and accepted in revised form February 18, 1992.

rectly transcribed to nursing hardex (16%), (2) flow meter off (34%), (3) oxygen delivery apparatus improperly worn (57%), (4) wrong fractional inspired oxygen concentration (58%). Im- proper transcription of antibiotic orders occurred on only one occasion (2%), and antibiotics were improperly administered in 5%. Arte- rial blood gas determinations preceded oxygen orders in 61%) whereas microbiologic cultures preceded antibiotic orders in 87% of the patients.

CONCLUSIONS: We conclude that oxygen therapy is neither prescribed nor administered with the same attention that is given to other drugs such as antibiotics. Oxygen prescription and/or delivery is associated with significantly greater error than that seen with antibiotics. Education of medical personnel should stress more prudent prescription and use of oxygen in hospitalized patients.

T he prescription of drugs for inpatients is done with considerable attention to the potential

benefit and toxicity of the specific agent. Extensive literature exists describing the pharmacokinetics of different drugs. Quality control studies have been performed to evaluate these issues with respect to commonly prescribed agents [1,2]. However, no such evaluation has been done with another commonly prescribed treatment, supplemental oxygen.

The therapeutic importance and potential toxicity of oxygen therapy are well known [3-61. It is a medication and should be governed by the same patterns of prescription and administration as other pharmaceutical agents [7-91. That process com- mences with the evaluation of the patient’s cardiopulmonary status using several measures including determination of oxygenation status with arterial blood gases or oximetry. The treating physician must then decide on the need for oxygen and write a written prescription on the “doctor’s order sheet,” specifying the dose (fractional inspired oxygen concentration [FiOz] or flow rate), route of administration (nasal prongs, face mask, tracheostomy collar), and period of administration (continuous, intermittent, nocturnal). This order is transcribed by the

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Drug administration in hospital follows a preset pattern:

Assessment of need I

M.D. order

Transcription of M.D. order to nursing kardex/medication kardex

Administration of drug by nursing staff

Figure 1. Prescription and administration procedure for hospitalized patients.

treating nurse into the “nursing kardex” or other reference and then the order is carried out. This also requires educating the patient about oxygen therapy and installing the equipment according to the specifications of the prescription (Figure 1).

In this study, we compared the prescription and administration of oxygen in individuals admitted to internal medicine wards with that in a similar group of internal medicine inpatients who were treated with antibiotics. The object was to determine whether the same degree of attention to detail was employed in the prescription and administration of these two commonly used therapies.

PATIENTS AND METHODS This study was conducted over 26 days in July

1990 at the Sir Mortimer B. Davis-Jewish General Hospital, a 600-bed McGill University teaching hospital All ward personnel were unaware of the nature of the study.

Admissions to the four medical wards were screened daily during the study period for eligibility criteria by two investigators (BW, AD). Patients included in the oxygen group either had oxygen apparatus at the bedside, a medical order indicating a new order for oxygen, or oxygen orders noted in the nursing kardex. Those patients entered into the antibiotic group had a new medical order for antibiotics or a nursing medication kardex notation for the delivery of antibiotics.

We attempted four random observations on 2 consecutive days of those individuals who were receiving oxygen according to a specific order. Con- gruence of medical order and nursing kardex nota-

, n n=96

USES AND MISUSES OF OXYGEN / SMALL ET AL

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Figure 2. Venn diagram depicting 96 patient observations for oxygen therapy. Ideally all observations should appear where the three required procedural criteria for oxygen use overlap.

tion was assessed in all cases. In patients receiving oxygen, observation was made for the presence of equipment for its delivery, and correct administration as per physician order. Specifically this included determining whether the flow meter was on or off, checking the FiOs, and determining if nasal prongs or face mask was being worn in a manner so as to permit oxygen delivery to the patient.

Auditing of the nursing medication kardex was done for four consecutive doses of antibiotics following the initial order, as to the congruence of physician order and nursing kardex notation, as well as the proper administration (i.e., correct dosage, and timing of delivery) of medication.

All patient charts were reviewed to determine if specific tests were done indicating the need for initiation of treatment, such as arterial blood gas analysis, oximetry, or, for those receiving antibiotics, microbiologic cultures.

Frequency distributions were assembled to ex- amine medication errors. Differences between error rates in oxygen and antibiotic administration were calculated using the chi-square technique. Actual p values are reported.

RESULTS During the 26-day period, there were 330 admis-

sions to the four medical wards. Of these, 96 patients were eligible for the study of oxygen therapy, and 60 were evaluated for antibiotic therapy. Of the 96 enrolled for the study of oxygen, 47 had medical orders for oxygen, 77 had nursing kardex notations, and in 86, oxygen equipment was found in the patient’s room (Figure 2).


/- Antibiotics

=60

Figure 3. Diagram depicting 60 patient observations in which antibiotics were ordered. In every case there was documentation of the medical order in the nursing medication kardex.

The proper sequence of prescription, nursing transcription, and subsequent administration of oxygen was followed in only 41 of 96 patients. Thir- ty-two patients had a nursing kardex notation for oxygen therapy without there having been a written medical order. Seventeen patients had oxygen equipment at the bedside without either a medical or nursing order. Conversely, oxygen was ordered in five patients, and in four of five instances this was noted by the nurses, yet oxygen equipment was not present at the bedside.

By comparison, all patients receiving antibiotics had proper medical orders with corresponding nursing medication kardex notation (Figure 3).

Of the 47 patients with a physician order for oxygen, 36 had a specific medical order (specifying FiOz, route of administration, and continuous delivery), whereas in the remaining 11 instances, oxygen was ordered by the physician as needed (PRN). Procedural errors, determined by kardex audit and direct patient observation, were compared for the individuals with a specific oxygen order and for those receiving antibiotics (Figure 4). The oxygen order had been transcribed incorrectly to the nursing kardex in six patients (16%). In three of these cases, the nursing kardex notation was for PRN oxygen, although this had not been specified in the medical order. In the three other patients, the nursing kardex showed a different concentration of oxygen than originally specified in the medical order. There was only one patient in the antibiotic group for whom the medical order had differed from the nursing medication kardex notation. In this case, an every-4-hour order had been recorded as every 6 hours.

There were 144 potential observations of oxygen use (four observations X 36 patients) and 240 observations of antibiotic use (four observations X 60 patients). We recorded 98 complete observations for oxygen use, and 228 for antibiotics. Missing data

60

wrongly flow meter improperly wrong transcribed off administered FIO2/ to nursing dosage

kardex

Figure 4. Errors in oxygen and antibiotic administration. Ex- amples of improper delivery include (1) oxygen masks/ prongs worn improperly and therefore oxygen not adequately delivered; (2) wrong dosing interval for antibiotics, e.g., every 6 hours ordered, every 4 hours delivered.

are due to patients not being available in their rooms for observations, usually because they were elsewhere undergoing investigational tests or because they had been discharged. The flow meter was off in 34% of observations in patients receiving oxygen. Oxygen was administered in a manner that would not allow oxygen delivery (mask not on face, nasal prongs not in nose) in 57% of the patient observations, whereas antibiotics were improperly administered (i.e., wrong time interval) in 5% of observations (p <O.OOOOOl) (Figure 4). The wrong concentration of oxygen had been administered in 58% of instances. In contrast, the wrong dosage of antibiotics was given to only one patient (2%), who received 400 mg of drug instead of 600 mg (p <0.000001).

Pretreatment assessment regarding initiation of therapy was done more frequently for antibiotics than for oxygen (p = 0.008). Of those patients who had arterial blood gas analysis or oximetry prior to the initiation of oxygen therapy, hypoxemia (oxygen tension [PO21 less than 60 torr or oximetry result less than 90%) was detected in 11 of 39 (28%). Reassessment of oxygen status with either a second blood gas analysis or oximetry during hospitalization was done in 14 patients (39%).

COMMENTS In this study, we have shown that oxygen is not

prescribed and administered with the same procedural care as other medications such as antibiotics. Specifically, oxygen was frequently administered without a written order. When there was such an order, the wrong concentration was administered in


USES AND MISUSES OF OXYGEN / SMALL ET AL -- .~ ---

over half the cases and often the flow meter had been turned off. These errors in prescription/use occurred despite clear authoritative medical and nursing literature declaring that oxygen is a drug and should be treated as such [g-12].

In this study, the initial need for oxygen treatment was evaluated by arterial blood gas analysis (or oximetry) in just 61% of patients, with reassessment done in only 39%. This occurred despite evidence in the literature attesting to the inability to reliably determine hypoxemia without accurate blood gas analysis or oximetry [ 13-151. Brougher et al [16] studied 77 patients for whom physicians had ordered oxygen. They found that in 30% of these patients, there was evidence of hypoxemia (PO2 less than 60 torr or oximetry result less than 90%). This is similar to the finding in this study, where 28% of patients were documented as hypoxemic. Thus, ju- dicious use of arterial blood gas determinations may obviate the need for oxygen. Consequent benefits would thereby include cost savings and the elimina- tion of potential oxygen toxicity.

There are several methodologic and practical factors that possibly affected the results of this study. One such is the possibility that the apparatus found in the patient’s room had been left over from a recently discharged patient, thus inflating the estimate of lack of the medical order. Even if this had been the case, it still reflects a lack of concern for oxygen, because any other prescribed medication would not have remained at the bedside following discharge of the patient.

The attempt to document correct patient use of oxygen equipment was done by several observations that were brief in nature. Had there been fewer observations for a longer interval, a different result might have been obtained. We chose this observation strategy in order to reflect the actual realities of patient care, over the course of several nursing shifts on consecutive days. In practice, when patients are observed for oxygen use, or func- tion of their intravenous lines, health care profes- sionals commonly make assessments at frequent yet brief intervals rather than by extended sessions.

This study highlights the difference in the way in which oxygen and antibiotics are used. The strict assessments of need, prescription, and administration of these agents were markedly different. The documentation of fewer errors in antibiotic delivery was dependent on the assumption that the notation in the medication kardex was correct. We did not attempt to verify that the dose was added to the soluset of the intravenous set and entered the patient, as was done with observations of oxygen delivery. Due to the intermittent and varied administration of antibiotics as compared with the

continuous administration of oxygen, it was not fea- sible to document the actual execution of antibiotic doses. Therefore, it is possible that some errors in administration of antibiotics were not recognized or recorded, and that the true error rate was underestimated.

It is well documented that medication errors that are either found or reported represent only a small fraction of the true error rate, and that under- reporting of medication errors of all types is pro- found [17,18]. Similarly, a study such as this has shortcomings that may lead to underdetection or misclassification of medication errors. It seems like- ly therefore that our results, if anything, may under- estimate the true error rate associated with oxygen administration.

Previously, many errors were not reported for fear of disciplinary action, including litigation. More recently, it is appreciated that reporting of errors is a means of establishing a system for con- structive problem solving so as to improve the quality of patient care [17]. Furthermore, it is now stressed that the action of an individual is rarely the sole cause of an incident but actually the culmina- tion of several contributory factors, resulting in error [19]. There are multiple factors that have affected the process of prescription and administration of oxygen, and subsequently led to the number and types of errors described in this study.

There are several ways to improve the process of oxygen prescription and administration. It is rec- ommended that oxygen prescription be guided by physiologic parameters on a much more consistent basis such as those specified by the American Col- lege of Chest Physicians-National Heart, Lung, and Blood Institute conference on oxygen therapy [8]. These guidelines maintain that supplemental oxygen is appropriate in acute conditions when the arterial oxygen tension is less than 60 torr, or when arterial saturation is below 90% by blood gas or oximetry. In addition, the American Thoracic Soci- ety Committee on oxygen therapy has clearly rec- ommended that oxygen is a drug that is to be administered for specific indications and in specific dosages. Moreover, the indications and effects of therapy can be accurately assessed by repeated arterial blood gas analysis [7]. Furthermore, there should be strict procedure and policy for prescribing oxygen, just as there exists for other medications. Oxygen should be prescribed on the same prescription forms used for other medications. The dose (FiOz) and method of delivery (nasal prongs versus face mask) should be stated explicitly. Once the prescription is written, it should be clearly recorded on a nursing medication card or flowsheet that will be incorporated into the patient’s perma-

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nent medical record [20,21]. This may be initialed daily by the nurse or respiratory therapist responsi- ble for oxygen administration to that patient. This technique has already been utilized with success for antibiotic prescription in an attempt to improve the delivery of that medication in hospitalized patients PA.

In conclusion, we found that the appropriate sequence of physician prescription, transcription to nursing records, and administration of oxygen is frequently not followed. Oxygen prescription and/ or delivery is associated with significantly greater error than that seen with antibiotics. It is recom- mended that comprehensive medical and nursing education should focus on the quality assurance of oxygen as a medical therapy, specifically its indications, prescription, and administration in the hospital setting. Finally, the initial and continued assessment of the patient’s oxygen needs during the course of hospitalization should be mandatory.

REFERENCES 1. Leape LL, Brennan TA, Laird NM, et al. The nature of adverse events of hospitalized patients. Results of the Harvard Medical Practice Study II. N Engl J Med 1991; 324: 377-84. 2. Brennan TA, Leape LL. Laird NM, et a/. Incidence of adverse events and negligence in hospitalized patients. Results of the Harvard Medical Practice Study. N Engl J Med 1991; 324: 370-6. 3. Priestly J. Experiments and observations on different kinds of air (1775). Reprinted in Alembic Club Reprints, Part I, No. 7. Chicago: University of Chicago Press, 1906.

4. Snider GL, Rinaldo JE. Oxygen therapy in medical patients hospitalized out- side of the intensive care unit. Am Rev Respir Dis 1980; 122 Suppl 5: 29-36. 5. Clark JM, Lambertsen CJ. Pulmonary toxicity: a review. Pharmacol Rev 1971;

23: 37-133. 6. Nash G, Blennerhassett JB. Pontoppidan H. Pulmonary lesions associated

with oxygen therapy and artificial ventilation. N Engl J Med 1967; 276: 368-74. 7. American Thoracic Society. Oxygen therapy in cardiopulmonary disease. A statement by the committee on therapy. Am Rev Respir Dis 1970; 101: 811-4. 8. Fulmer JD. Snider GL. ACCP-NHLBI National Conference on oxygen therapy. Chest 1984; 86: 236-47. 9. Petty TL. Misunderstanding concerning the proper clinical use of oxygen. Ann Intern Med 1969; 70: 645-6. 10. Campbell EJM. A method of controlled oxygen administration which reduces the risk of carbon-dioxide retention. Lancet 1960; 2: 12-4. 11. Allan D. Making sense of oxygen delivery. Nurs Times 1989; 85: 40-2. 12. Bolgiano CS, Bunting K, Shoenberger MM. Administering oxygen therapy: what you need to know. Nursing 1990; 20: 47-51. 13. Block ER. Oxygen therapy. In: Fishman AP, editor. Update: pulmonary diseases and disorders. New York: McGraw-Hill, 1982: 349-65. 14. Mithoefer JC. Karetzky MS, Mead GD. Oxygen therapy in respiratory failure. N Engl J Med 1967; 277: 947-9. 15. Bendixen HH, Egbert LD. Hedley-Whyte J, Laver MB, Pontoppidan H. Oxy- gen therapy. In: Bendixen HH, Egbert LD, Hedley-Whyte J. Laver MB, Pontoppi-

dan H. editors. Respiratory care. St. Louis: Mosby, 1965: 126-36. 16. Brougher LI. Blackwelder AK, Grossman GD, Satton GW. Effectiveness of medical necessity guidelines in reducing cost of oxygen therapy. Chest 1986; 90: 646-8. 17. Fruqua RA. Stevens KR. What we know about medication errors: a literature review. J Nurs Qual Assur 1988; 3: 1-17. 18. Jesse WF. Medication errors noted as major source of incident reports. Hospital Peer Review 1981; 39: 141-3. 19. Blake P. Incident investigation: a complete guide. Nursing Management 1984; 15: 37-41.

20. Sinha L, Driedger M. Dick J. Patient focused charting. Can J Nurs Adm 1988; 1: 20-2. 21. Brider P. Who killed the nursing care plan? Am J Nurs 1991; 91: 35-9. 22. Kowalsky SF, Echols RM, Peck F. Reprinted order sheet to enhance antibiotic prescribing and surveillance. Am J Hosp Pharm 1982; 39: 1528-9.


uses and misuses of oxygen in hospitalized patients

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