Ciprofloxacin-phenytoin interaction TOTHEEDITOR: Ciprofloxacin is a synthetic, broad-spectrum antimicrobial agent available in both oral and intravenous forms, Various drug interactions involving ciprofloxacin and the methylxanthines theophylline and caffeine have been reported and have resulted in up to a 22.8 percent increase in steady-state theophylline concentrations. Ciprofloxacin-induced involvement of the cytochrome P-450 oxidative enzymes has been proposed as the mechanism. 1 Changes in plasma phenytoin concentrations when administered concurrently with ciprofloxacin have been recognized by the manutacturer,' but to date, no literatureconcerning a ciprofloxacin-induced decrease in serum phenytoin concentration has been reported. We report the following case. A 78-year-old manwashospitalized withfever andweakness andwassubsequently diagnosed with lower left-lobe abscess secondary to aspiration pneumonia. Ceftriaxone therapy wasbegun andthepatient wascontinued on phenytoin 300mg/d fora history of seizure disorder that began after a cerebral vascular accident in 1987. With little clinical improvement byday7,ceftriaxone was discontinuedandciprofloxacin 400mgq12h iv was started. Thephenytoin serum concentration onday6 was 14.7 mg/L. On day 8, thephenytoin serum concentration was 6.3mg/L. Thephenytoin dose was increased to400mg/d following breakthrough seizures. Phenytoin serum concentration onday9 was 4.8mg/L andthedose then wasincreased to 500mg/d. The phenytoin serum concentrations ondays 10-20 were 8-11 mg/L andno seizures occurred. Onday20.ciprofloxacin wasdiscontinued aftersubstantial clinical improvement and phenytoin wascontinued at a dose of 500mg/d. On day21,thephenytoin concentrations were 13.7 mg/L and thedosage of 500mg/d wascontinued. Thepatient then was discharged. Seizures have been reported to occur with ciprofloxacin as well as other quinolone agents.' Further study is needed to determine possible mechanisms for the ciprofloxacin-phenytoin interaction. MIKE L. DILLARD, Phann.D.
JuniorMedicalStudent James H. QuillenCollegeofMedicine ROBERT M. FINK, Phann.D.. M.B.A ClinicalPharmacy Coordinator JohnsonCity MedicalCenterHospital 400 State of FranklinRoad JohnsonCity, Tennessee 37604 ClinicalAssistantProfessor JamesH. QuillenCollegeofMedicine East Tennessee State University Johnson City, Tennessee ROBERT PARKERSON, D.Ph.
proximately fouryears agoandsustained severe head trauma, which ledtopossibleinterference with theproduction or release ofgrowth hormone. Hehasalso experienced tonic/clonic seizures andhypothyroidism asa result; these arewell controlled with divalproex sodium andlevothyroxine sodium. Arginine HCI 10% was the diagnostic agent used to stimulate theproduction andrelease of growth hormone. It wasinfused through a peripheral intravenous site in the rightfoot at a dose of 500 mg/kg (approximately 120mL) over a period of 30 minutes (4 mLImin). Thepatient appeared to be uncomfortable during theinfusion, at which time thenurse administering thedrug noticed puffmess at theiv site. Theinfusion was immediately discontinued andtheivwas removed from theinfusion site. The areabegan to blister rapidly anddeveloped intofull-thickness necrosis within a matter of hours. Thepatient hadreceived 74 mLof the 120-mL dose. Hewas admitted tothebumunit ofourinpatient children's hospital fordebridement andsubsequent skin grafting. Hewasdischarged 16days later. Baker and Franklin recently reported on a seven-year-old white boy with known argininosuccinic aciduria. Because of sudden deterioration in his mental status, the patient was hospitalizedfor intravenous arginine therapy. The child was initially treated with an infusion of 10% arginine at a rate of 6 mL/h for a total volume of 150 mL. Four hours after the infusion was initiated,the iv site became edematous, red, and painful, and the infusion was stopped. Forty-eight hours later the traumatized area closely resembled a full-thickness bum. As a result, a skin graft was required. No permanent damage was observed on follow-up examination.' Several chemotherapeutic agents are known to cause necrosis upon extravasation. These agents produce toxic effects according to their unique mechanism of actions upon the cell. Excluding these agents, the necrosis-producingmechanism of extravasation-induced injury is one of profound local alterations in either tissue pH or osmolarity.' There are two proposed mechanisms by which arginine causes necrosis upon extravasation. First, the 10% solution of arginine is extremely hyperosmolar (950 mOsmol/L). Second, arginine is thought to produce profoundly irritating local hyperkalemia in the area of extravasation secondary to an arginine-induced shift of potassium ions from the intracellular to extracellular compartments.t-" Prevention of arginine-induced necrosis is the best treatment. Baker and Franklin propose diluting the 10% solution of arginine to an isosmolar concentrationbefore infusionto prevent tissue injuryshould accidental extravasation occur. Other preventive methods include frequent assessment of iv patency and limitedmovement of the patient during infusion.' It is importantfor clinicians administering iv arginine HCI to beaware of the potential for extravasationand subsequenttissue necrosis.Extravasation of arginine HCI can extend an outpatient clinic visit into a lengthy inpatient admission with the potential for skin graftingand infection. HOLLY A. BOWLBY
ClinicalPharmacist Johnson City MedicalCenterHospital
Pharm.D, Student SONA I. ELANflAN, Pharm.D.
REFERENCES
1. Wigands WJA, Vree TB, Van Herwaarden CLA. The influence of
quinolone derivatives on theophylline clearance. Br J ClinPharmacol 1986;22:677-83. 2. Package insert. Cipro (ciprofloxacin). Miles Inc. pharmaceutical division.WestHaven, CT, Oct. 1987. 3. Anastasio GD, Menscer D, Little JM Jr. Norfloxacin and seizures (letter). AnnIntern Med 1988;109:169-70. Necrosis caused by extravasation of arginine hydrochloride TO THEEDITOR: Arginine hydrochloride (HCI) administered intravenously is one of several diagnostic agents used to test for growth hormone reserve in patients with suspected growth hormone deficiency.'? Other diagnostic agents include insulin, levodopa, and glucagon.' Arginine stimulates the release of pituitary growth hormone as a result of its effects on the hypothalamus. In patients with intact pituitary function, iv arginine produces a pronounced rise in plasma concentrations of human growth hormone usually in the range of 10-30 ng/mL within one hour after initiating the infusion. Growth hormone concentrations of :54 ng/mL indicate pituitary growth hormone deficiency.l-' Adverse effects of iv arginine HO previously reported in the literature include phlebitis, flushing, and nonspecific local venous irritation." To our knowledge, necrosis due to extravasation has only been reported once in the literature.' We report on a patient who experienced necrosis following the infusion of arginine HC!. Aneight-year-old white boy wasseen in our outpatient clinicfor testing of growth hormone deficiency. Thechild was involved inanautomobile accident ap-
AssistantProfessorof PharmacyPractice Collegeof Pharmacy Butler University Drug Information Specialist IndianaUniversity Hospitals Indianapolis, Indiana46202 REFERENCES
I. Parker ML, Hammond JM, Daughaday WHo The arginineprovocative test: an aid in the diagnosis of hyposomatotropism. J Clin Endoerinol Metab 1967;27:1129-36. 2. Raiti S, Davis WT, Blizzard RM. A comparison of the effects of insulin hypoglycemia and arginineinfusion on releaseof humangrowthhormone.Lancet 1967;2:1182-3. 3. Root AW, Saenz-Rodriguez C, Bongiovanni AM, Eberlein WR. The effect of arginine infusionon plasma growth hormoneand insulinin children.J Pediatr 1969;74:187-97. 4. Jubiz W. Endocrinology. New York: McGraw-Hill, 1979:12-3. 5. Imler M, Rushcer H, Peter B, Cook H. The effectof arginine in a case of recurrent hepatic comacomplicating a feminizing corticoadrenal tumor withhepatic metastasis. Semin Hosp Paris 1973;49:3183-90. 6. Paton W. L-arginine-induced hypotension. Lancet 1990;336:1016-7. 7. Baker GL, Franklin JD. Management of argininemonohydrochloride extravasation in the forearm. South MedJ 1991 ;84:381-4. 8. Johnson CA, Lloyd JC. Hydrochloric acid for the correction of severe metabolic alkalosis: an alternative approach. J Ky MedAssoc 1977;75: 121-3.
The Annals ofPharmacotherapy
•
1992 February, Volume 26
•
263
9. Martin WJ, Matzke GR. Treating severe metabolic alkalosis. Clin
Pharm 1982;1:42-8. 10. Barbul A. Arginine: biochemistry, physiology and therapeutic implications. IPENI Parenter Enteral Nutr 1986;10:227-38. Positive effect of pharmaceutical care interventions in an internal medicine inpatient setting TO TIIE EDITOR: There is an ongoing need to document the cost-effectiveness of clinical pharmacy services and improvements in patient care. Articles have described methods to document positive patient outcomes based on pharmaceutical care interventions.v! We describe the results of a method to evaluate the impact of such interventions at the University of Cincinnati Medical Center, a 692-bed, teaching facility. Pharmaceutical care on the two nonintensive care internal medicine nursing units is provided by two clinical pharmacy practitioners (CPPs) and a decentralized pharmacist. Pharmacy residents and Phann.D. students also participate under the direction of the CPPs. The study commenced January 2, 1990 and continued until April 30, 1990. During that time, participants documented all interventions that were initiated by the pharmacists on the service. Interventions were defmed as changes in drug therapy or laboratory tests and were subcategorized as listed in Table 1. All patients were followed until discharge to document the effect of the intervention on patient outcome using a preprinted monitoring sheet. In addition, physicians on the service were asked to complete an anonymous questionnaire at the end of each month to elicit their opinion of the effect of pharmaceutical services on the outcome of their patients' care. The costs of changes in drug therapy were calculated by subtracting the acquisition cost of the new drug regimen from the cost of the old drug regimen. The resulting figure was multiplied by the number of doses the intervention affected. For drugs without a definite length of therapy, the following durations were assigned: (I) maintenance medications: number of doses until discharge; (2) change in route: 48 hours; (3) discontinuation of nonmaintenance medication: 48 hours; and (4) discharge medications: one month. Costs of laboratory values (including serum drug concentrations) requested or discontinued by the pharmacist were assessed using hospital Table 1. Number of Interventions by Category and Their Impact on Cost
Category A: Changes in drug therapy dose change frequency change therapeutic change route change change to formulary item allergy/ ADRICI drug-drug interaction TOTAL
Category B: Discontinue drug therapy adequate treatment course duplication of treatment" inappropriate treatment allergy/ADR/CI TOTAL
Breakdown of categories A and B Hz-antagonists antimicrobials Category C: Laboratory tests laboratory tests discontinued laboratory tests recommended Category D: Additions to drug therapy additions Category E: Inservice/education TOTAL A+B+C+D+E
n(%)
($)
40 (11.0) 33 (9.0) 36 (9.9) 54 (14.9) 4 (1.1) 16 (4.4) 4 (1.1) 187 (51.5)
+ 8356.31
25 (6.9) 31 (8.5) 24 (6.6) 30 (8.3) 110 (30.3)
+ 8019.56
50 (14.0) 133 (37.0)
3298.52 5339.00
AdjunctClinicalProfessor Collegeof Medicine WrightState University Dayton,Ohio ClinicalPharmacist Good Samaritan Hospital Departmentof PharmacyService 2222 Philadelphia Drive Dayton,Ohio 45406 PATRICE M. KRSTENASKY, Pharm.D.
AdjunctAssociateProfessorof Clinicaland HospitalPharmacy (at time of study) Collegeof Pharmacy University ofCincinnati ClinicalPharmacist in InternalMedicine University ofCincinnati MedicalCenter Cincinnati, Ohio Drug Use Evaluation Pharmacist (at present) StanfordUniversity Hospital Stanford, California REFERENCES
18 16
(5.0) (4.4)
14 (3.9) 18 (5.0) 363 (100.0)
+
165.00 128.00 71.06 0.00 16341.81
"This category included the $4836.00 immunologic intervention. ADR = adverse drug reaction; CI = contraindication.
264 •
MARYANNE MASTERS, Pharm.D.
ClinicalPharmacyResident(at timeof study) University of Cincinnati MedicalCenter Cincinnati, Ohio AdjunctAssociateProfessor(at present) Collegeof Pharmacy Ohio Nonhern University Ada.Ohio
COST AVOIDANCE INTERVENTIONS
cost of the value, not patient charge. Costs of both the therapy and laboratory interventions included the costs of packaging supplies. Cost calculations did not include cost of pharmacy preparation, nursing administration, or phlebotomy time. Although efforts to educate physicians, detain adverse effects and allergic reactions, and patient outcome were monitored, no actual costs were assigned to them. During the study period, a total of 363 interventions were made. Physician acceptance rate of interventions was 90 percent. The number of interventions in each category are presented in Table I. Most interventions were related to Hz-antagonists, antimicrobials, route changes, and dosing of patients with renal dysfunction. One discontinuation of an improper dose of an immunologic agent resulted in a $4836.00 cost avoidance, signifying that small interventions in biotechnology can have great cost impact. Overall, cost-avoidance totaled $16 341.81 during the study period. Only one recommendation resulted in an adverse event. An allergic reaction, interstitial nephritis, occurred in a patient with no known drug allergies at the time of the recommendation. In contrast, pharmacists documented 50 interventions (14 percent) that resulted in potential or actual avoidance of an adverse drug effect. The other interventions were not deemed to be detrimental to patient care, but no assessment was made as to their potential benefit on outcome. Eighty of 91 physicians surveyed (88 percent) responded to our questionnaire. Physicians were asked to rate the effect of pharmaceutical care on patient outcome on a scale of 1-10 (I = no benefit, 10 = very beneficial). The care given by the pharmacists received a mean rating of 8.4, indicating the value of patient-oriented pharmacy services in this setting. The study described here has many limitations in method design and the simplicity of the accounting methods described. However, it has served as an initial tool to survey the value of our service to patient care, and to aid our development of targeted intervention programs. This clinical pharmacy service had a positive impact on cost and outcome of patient care in the internal medicine setting. Pharmacists should be encouraged to pursue methods to document the impact of pharmaceutical care.
I. Chrischilles EA, Helling DK, Aschoff CR. Effect of clinical pharmacy services on the quality of family practice physician prescribing and medicationcosts. D1CP AnnPharmacotherl 989;23:417-21. 2. Hatoum HT, Hutchinson RA, Witte KW, Newby GP. Evaluation of the contribution of clinical pharmacists: inpatient care and cost reduction. Drug lntellClinPharm 1988;22:252-9. 3. Hatoum HT, Hutchinson RA, Elliott LR, Kendzierski DL. Physicians' review of significant interventions by clinical pharmacists in inpatient care. Drug Intell ClinPharm 1988;22:980-2.
The Annals ofPharmacotherapy • 1992 February, Volume26
JuniorMedicalStudent James H. QuillenCollegeofMedicine ROBERT M. FINK, Phann.D.. M.B.A ClinicalPharmacy Coordinator JohnsonCity MedicalCenterHospital 400 State of FranklinRoad JohnsonCity, Tennessee 37604 ClinicalAssistantProfessor JamesH. QuillenCollegeofMedicine East Tennessee State University Johnson City, Tennessee ROBERT PARKERSON, D.Ph.
proximately fouryears agoandsustained severe head trauma, which ledtopossibleinterference with theproduction or release ofgrowth hormone. Hehasalso experienced tonic/clonic seizures andhypothyroidism asa result; these arewell controlled with divalproex sodium andlevothyroxine sodium. Arginine HCI 10% was the diagnostic agent used to stimulate theproduction andrelease of growth hormone. It wasinfused through a peripheral intravenous site in the rightfoot at a dose of 500 mg/kg (approximately 120mL) over a period of 30 minutes (4 mLImin). Thepatient appeared to be uncomfortable during theinfusion, at which time thenurse administering thedrug noticed puffmess at theiv site. Theinfusion was immediately discontinued andtheivwas removed from theinfusion site. The areabegan to blister rapidly anddeveloped intofull-thickness necrosis within a matter of hours. Thepatient hadreceived 74 mLof the 120-mL dose. Hewas admitted tothebumunit ofourinpatient children's hospital fordebridement andsubsequent skin grafting. Hewasdischarged 16days later. Baker and Franklin recently reported on a seven-year-old white boy with known argininosuccinic aciduria. Because of sudden deterioration in his mental status, the patient was hospitalizedfor intravenous arginine therapy. The child was initially treated with an infusion of 10% arginine at a rate of 6 mL/h for a total volume of 150 mL. Four hours after the infusion was initiated,the iv site became edematous, red, and painful, and the infusion was stopped. Forty-eight hours later the traumatized area closely resembled a full-thickness bum. As a result, a skin graft was required. No permanent damage was observed on follow-up examination.' Several chemotherapeutic agents are known to cause necrosis upon extravasation. These agents produce toxic effects according to their unique mechanism of actions upon the cell. Excluding these agents, the necrosis-producingmechanism of extravasation-induced injury is one of profound local alterations in either tissue pH or osmolarity.' There are two proposed mechanisms by which arginine causes necrosis upon extravasation. First, the 10% solution of arginine is extremely hyperosmolar (950 mOsmol/L). Second, arginine is thought to produce profoundly irritating local hyperkalemia in the area of extravasation secondary to an arginine-induced shift of potassium ions from the intracellular to extracellular compartments.t-" Prevention of arginine-induced necrosis is the best treatment. Baker and Franklin propose diluting the 10% solution of arginine to an isosmolar concentrationbefore infusionto prevent tissue injuryshould accidental extravasation occur. Other preventive methods include frequent assessment of iv patency and limitedmovement of the patient during infusion.' It is importantfor clinicians administering iv arginine HCI to beaware of the potential for extravasationand subsequenttissue necrosis.Extravasation of arginine HCI can extend an outpatient clinic visit into a lengthy inpatient admission with the potential for skin graftingand infection. HOLLY A. BOWLBY
ClinicalPharmacist Johnson City MedicalCenterHospital
Pharm.D, Student SONA I. ELANflAN, Pharm.D.
REFERENCES
1. Wigands WJA, Vree TB, Van Herwaarden CLA. The influence of
quinolone derivatives on theophylline clearance. Br J ClinPharmacol 1986;22:677-83. 2. Package insert. Cipro (ciprofloxacin). Miles Inc. pharmaceutical division.WestHaven, CT, Oct. 1987. 3. Anastasio GD, Menscer D, Little JM Jr. Norfloxacin and seizures (letter). AnnIntern Med 1988;109:169-70. Necrosis caused by extravasation of arginine hydrochloride TO THEEDITOR: Arginine hydrochloride (HCI) administered intravenously is one of several diagnostic agents used to test for growth hormone reserve in patients with suspected growth hormone deficiency.'? Other diagnostic agents include insulin, levodopa, and glucagon.' Arginine stimulates the release of pituitary growth hormone as a result of its effects on the hypothalamus. In patients with intact pituitary function, iv arginine produces a pronounced rise in plasma concentrations of human growth hormone usually in the range of 10-30 ng/mL within one hour after initiating the infusion. Growth hormone concentrations of :54 ng/mL indicate pituitary growth hormone deficiency.l-' Adverse effects of iv arginine HO previously reported in the literature include phlebitis, flushing, and nonspecific local venous irritation." To our knowledge, necrosis due to extravasation has only been reported once in the literature.' We report on a patient who experienced necrosis following the infusion of arginine HC!. Aneight-year-old white boy wasseen in our outpatient clinicfor testing of growth hormone deficiency. Thechild was involved inanautomobile accident ap-
AssistantProfessorof PharmacyPractice Collegeof Pharmacy Butler University Drug Information Specialist IndianaUniversity Hospitals Indianapolis, Indiana46202 REFERENCES
I. Parker ML, Hammond JM, Daughaday WHo The arginineprovocative test: an aid in the diagnosis of hyposomatotropism. J Clin Endoerinol Metab 1967;27:1129-36. 2. Raiti S, Davis WT, Blizzard RM. A comparison of the effects of insulin hypoglycemia and arginineinfusion on releaseof humangrowthhormone.Lancet 1967;2:1182-3. 3. Root AW, Saenz-Rodriguez C, Bongiovanni AM, Eberlein WR. The effect of arginine infusionon plasma growth hormoneand insulinin children.J Pediatr 1969;74:187-97. 4. Jubiz W. Endocrinology. New York: McGraw-Hill, 1979:12-3. 5. Imler M, Rushcer H, Peter B, Cook H. The effectof arginine in a case of recurrent hepatic comacomplicating a feminizing corticoadrenal tumor withhepatic metastasis. Semin Hosp Paris 1973;49:3183-90. 6. Paton W. L-arginine-induced hypotension. Lancet 1990;336:1016-7. 7. Baker GL, Franklin JD. Management of argininemonohydrochloride extravasation in the forearm. South MedJ 1991 ;84:381-4. 8. Johnson CA, Lloyd JC. Hydrochloric acid for the correction of severe metabolic alkalosis: an alternative approach. J Ky MedAssoc 1977;75: 121-3.
The Annals ofPharmacotherapy
•
1992 February, Volume 26
•
263
9. Martin WJ, Matzke GR. Treating severe metabolic alkalosis. Clin
Pharm 1982;1:42-8. 10. Barbul A. Arginine: biochemistry, physiology and therapeutic implications. IPENI Parenter Enteral Nutr 1986;10:227-38. Positive effect of pharmaceutical care interventions in an internal medicine inpatient setting TO TIIE EDITOR: There is an ongoing need to document the cost-effectiveness of clinical pharmacy services and improvements in patient care. Articles have described methods to document positive patient outcomes based on pharmaceutical care interventions.v! We describe the results of a method to evaluate the impact of such interventions at the University of Cincinnati Medical Center, a 692-bed, teaching facility. Pharmaceutical care on the two nonintensive care internal medicine nursing units is provided by two clinical pharmacy practitioners (CPPs) and a decentralized pharmacist. Pharmacy residents and Phann.D. students also participate under the direction of the CPPs. The study commenced January 2, 1990 and continued until April 30, 1990. During that time, participants documented all interventions that were initiated by the pharmacists on the service. Interventions were defmed as changes in drug therapy or laboratory tests and were subcategorized as listed in Table 1. All patients were followed until discharge to document the effect of the intervention on patient outcome using a preprinted monitoring sheet. In addition, physicians on the service were asked to complete an anonymous questionnaire at the end of each month to elicit their opinion of the effect of pharmaceutical services on the outcome of their patients' care. The costs of changes in drug therapy were calculated by subtracting the acquisition cost of the new drug regimen from the cost of the old drug regimen. The resulting figure was multiplied by the number of doses the intervention affected. For drugs without a definite length of therapy, the following durations were assigned: (I) maintenance medications: number of doses until discharge; (2) change in route: 48 hours; (3) discontinuation of nonmaintenance medication: 48 hours; and (4) discharge medications: one month. Costs of laboratory values (including serum drug concentrations) requested or discontinued by the pharmacist were assessed using hospital Table 1. Number of Interventions by Category and Their Impact on Cost
Category A: Changes in drug therapy dose change frequency change therapeutic change route change change to formulary item allergy/ ADRICI drug-drug interaction TOTAL
Category B: Discontinue drug therapy adequate treatment course duplication of treatment" inappropriate treatment allergy/ADR/CI TOTAL
Breakdown of categories A and B Hz-antagonists antimicrobials Category C: Laboratory tests laboratory tests discontinued laboratory tests recommended Category D: Additions to drug therapy additions Category E: Inservice/education TOTAL A+B+C+D+E
n(%)
($)
40 (11.0) 33 (9.0) 36 (9.9) 54 (14.9) 4 (1.1) 16 (4.4) 4 (1.1) 187 (51.5)
+ 8356.31
25 (6.9) 31 (8.5) 24 (6.6) 30 (8.3) 110 (30.3)
+ 8019.56
50 (14.0) 133 (37.0)
3298.52 5339.00
AdjunctClinicalProfessor Collegeof Medicine WrightState University Dayton,Ohio ClinicalPharmacist Good Samaritan Hospital Departmentof PharmacyService 2222 Philadelphia Drive Dayton,Ohio 45406 PATRICE M. KRSTENASKY, Pharm.D.
AdjunctAssociateProfessorof Clinicaland HospitalPharmacy (at time of study) Collegeof Pharmacy University ofCincinnati ClinicalPharmacist in InternalMedicine University ofCincinnati MedicalCenter Cincinnati, Ohio Drug Use Evaluation Pharmacist (at present) StanfordUniversity Hospital Stanford, California REFERENCES
18 16
(5.0) (4.4)
14 (3.9) 18 (5.0) 363 (100.0)
+
165.00 128.00 71.06 0.00 16341.81
"This category included the $4836.00 immunologic intervention. ADR = adverse drug reaction; CI = contraindication.
264 •
MARYANNE MASTERS, Pharm.D.
ClinicalPharmacyResident(at timeof study) University of Cincinnati MedicalCenter Cincinnati, Ohio AdjunctAssociateProfessor(at present) Collegeof Pharmacy Ohio Nonhern University Ada.Ohio
COST AVOIDANCE INTERVENTIONS
cost of the value, not patient charge. Costs of both the therapy and laboratory interventions included the costs of packaging supplies. Cost calculations did not include cost of pharmacy preparation, nursing administration, or phlebotomy time. Although efforts to educate physicians, detain adverse effects and allergic reactions, and patient outcome were monitored, no actual costs were assigned to them. During the study period, a total of 363 interventions were made. Physician acceptance rate of interventions was 90 percent. The number of interventions in each category are presented in Table I. Most interventions were related to Hz-antagonists, antimicrobials, route changes, and dosing of patients with renal dysfunction. One discontinuation of an improper dose of an immunologic agent resulted in a $4836.00 cost avoidance, signifying that small interventions in biotechnology can have great cost impact. Overall, cost-avoidance totaled $16 341.81 during the study period. Only one recommendation resulted in an adverse event. An allergic reaction, interstitial nephritis, occurred in a patient with no known drug allergies at the time of the recommendation. In contrast, pharmacists documented 50 interventions (14 percent) that resulted in potential or actual avoidance of an adverse drug effect. The other interventions were not deemed to be detrimental to patient care, but no assessment was made as to their potential benefit on outcome. Eighty of 91 physicians surveyed (88 percent) responded to our questionnaire. Physicians were asked to rate the effect of pharmaceutical care on patient outcome on a scale of 1-10 (I = no benefit, 10 = very beneficial). The care given by the pharmacists received a mean rating of 8.4, indicating the value of patient-oriented pharmacy services in this setting. The study described here has many limitations in method design and the simplicity of the accounting methods described. However, it has served as an initial tool to survey the value of our service to patient care, and to aid our development of targeted intervention programs. This clinical pharmacy service had a positive impact on cost and outcome of patient care in the internal medicine setting. Pharmacists should be encouraged to pursue methods to document the impact of pharmaceutical care.
I. Chrischilles EA, Helling DK, Aschoff CR. Effect of clinical pharmacy services on the quality of family practice physician prescribing and medicationcosts. D1CP AnnPharmacotherl 989;23:417-21. 2. Hatoum HT, Hutchinson RA, Witte KW, Newby GP. Evaluation of the contribution of clinical pharmacists: inpatient care and cost reduction. Drug lntellClinPharm 1988;22:252-9. 3. Hatoum HT, Hutchinson RA, Elliott LR, Kendzierski DL. Physicians' review of significant interventions by clinical pharmacists in inpatient care. Drug Intell ClinPharm 1988;22:980-2.
The Annals ofPharmacotherapy • 1992 February, Volume26
