1.gif (1892 bytes)

Original Articles

Indian Pediatrics 2001; 38: 340-348  

COMPARATIVE EFFICIENCY OF COMMERCIAL AND IMPROVISED SPACER 
DEVICE IN ACUTE BRONCHIAL ASTHMA


Jyoti Panicker, 
G.R. Sethi and 
Vineet Sehgal

From the Department of Pediatrics, Maulana Azad Medical College, New Delhi 110 002, India.
Correspondence to: Dr. G.R. Sethi, Professor, Department of Pediatrics, Maulana Azad Medical College, New Delhi 110 002, India.

Manuscript received: August 5, 1999; Initial Review completed: September 16,1999;
Revision accepted: October 4, 2000.

Objective: To compare the efficacy of a commercial spacer device versus an improvised spacer device in delivering aerosolized beta-2 agoinst through metered dose inhaler in an acute exacerbation of bronchial asthma. Design: Radomized controlled trial. Setting: Urban tertiary care teaching hospital. Methods: 60 children between 1 to 12 years of age with acute asthma were prospectively enrolled and randomized into two groups. Detailed history, clinical evaluation and appropriate laboratory investigations were recorded on a pretested proforma. One group received inhaled salbutamol using metered dose inhaler via commercial spacer device (Group 1), while the other received it via improvised spacer device (Group II). The response was sequentially assessed after 20, 40 and 60 minutes of institution of therapy. Results: The two groups were comparable with respect to various parameters at presentation (p >0.05). All the outcome parameters showed a significant improvement with time in both groups (p <0.05). There was no statistical difference between the response in the two groups (p <0.05). Conclusion: Metered dose inhaler with improvised spacer device is equivalent in efficacy and a more cost effective alternative to metered dose inhaler with commercial spacer for administration of beta–2 agonist in acute asthma.

Key words: Acute asthma, Beta-2 agonist, Spacer.

BRONCHIAL asthma is a common respiratory disease of childhood. Acute exacebration of asthma is a common, poten-tially life threatening complication. Various guidelines(1-4) have been laid down for the management of asthma. Aerosolized beta-2 agonists are the drugs of choice for an acute exacerbation of bronchial asthma(1). The inhalation route is preferred because of its greater efficacy(5). Recent studies have shown that there is no significant difference between nebulizer and metered dose inhaler (MDI) with spacer for delivery of aerosolized bronchodilators in acute asthma(6-8). In contrast to a nebulizer, MDI with spacer is cheaper, portable, easier to use, less time consuming and needs no power supply(9). Use of spacer eliminates the need for co-ordination of aerosol actuation with inspiration(10) and also decreases oropharyngeal deposi-tion(11,12). Commercial spacers are still expensive and may not be available every-where making it difficult to replace them in case of loss or damage.

Indigenous spacer made from a plastic bottle is very cheap and can be made at home, making it easily replaceable. Various authors(13-15) have used indigenous spacers, e.g., coffee cups, plastic bags and found them to be effective in achieving bronchodilation and decreasing oropharyngeal deposition. However, there is paucity of data comparing the efficacy of indigenous spacer with the commercial spacer. The present study was therefore designed to compare the efficacy of valved commercial spacer with non-valved indigenous spacer for delivering aerosolized beta-2 agonist in an acute exacerbation of asthma.

 Subject and Methods

The study was conducted in the Pediatric Emergency Room. Children between 1 to 12 years of age, seeking treatment for an acute exacerbation of bronchial asthma were eligible for enrolment in the study. Bronchial asthma was defined as per Sibbald’s criteria(16) as: "Recurrent episodes of wheezing which occur in response to allergens, exercise or emotions as well as with symptoms suggestive of respiratory infection. On auscultation there would be high pitched wheeze over most parts of the lung". For the purpose of the study, a child should have had at least two such previous episodes and should not have pulmonary tuberculosis, emphysema other cardiac, hepatic, pulmonary or skeletal disease involving the spine or any neuromuscular disorder involving intercostal muscle or diaphragm. Infants were excluded from the study. Children who had already received steroids for the presenting exacerbation of asthma before coming to hospital were also excluded. An informed consent was obtained from parents prior to recruitment.

Following recruitment, the children were randomized (computer generated random numbers) into two treatment groups. Group I comprised children who received salbutamol by MDI with commercially available spacer (M/s. Cipla conical valved spacer made of plastic with approximate volume of 750 ml) with or without attached face mask and Group II of those who received salbutamol by MDI with indigenous (improvised) spacer made from a bottle. The commonly available plastic water bottle (1 litre) was adapted to approximate the volume of commercial spacer (750 ml) by cutting it at its mouth-end. The cut-end was padded with plastic adhesive to make it non-traumatic. The base of the bottle was adapted to the MDI mouth piece by cutting in the center, so as to cause minimal leakage of aerosol. The indigenous spacer was tubular and without a valve.

A detailed clinical evaluation (history and examination) was recorded on a pre-decided proforma and the severity (mild, moderate, severe) of the acute episode assessed as per guidelines(1). Investigations included peak expiratory flow rate (PEFR) by Wright’s peak flow meter in subjects able to undergo the evaluation and arterial blood gas analysis. After assessment of severity of the attack, all patients were treated according to consensus protocols and no life saving treatment was withheld. Children were given 2 puffs of salbutamol (100 mg) with a gap of 1-2 minutes between the puffs, every 5-10 minutes, using metered dose inhaler with either of the spacers for a total duration of one hour. A face mask was used with commercial spacer in children less than 3 years of age, or in children too sick to use a spacer without a mask. Humidified oxygen was given to all patients at a flow rate of 3-4 L/min. Children were sequentially assessed at 20, 40 and finally at 60 minutes by a single observer (JP) to assess the response to inhaled salbutamol. Response was graded as good, partial or poor as per the guidelines. Cases with incomplete or poor response at 60 minutes were given further treatment according to consensus protocols. children with good response continued to receive inhalation of salbutamol for one hour, frequency of which was gradually decreased and were discharged after a period of stabilization. The differences between the groups were analyzed by chi-square test, Fischer exact test, Student ‘t’ test and analysis of variance, wherever applicable.

 Results

Sixty children (30 in each group) fulfilling the study criteria were evaluated. The two groups were comparable (p ³ 0.05) for various characteristics at admission (Table I). The sequential changes in the outcome measures evaluated at 20, 40 and 60 minutes are summarized in Table II. All the outcome measures showed a significant (p <0.05) improvement with time in both the groups, indicating the efficacy of both the spacer devices. After institution of therapy, all the recovery parameters including clinical criteria, PEFR and blood gases were comparable (p ³ 0.05) at all observation points, i.e., 20, 40 and 60 minutes after institution of therapy in the two groups.

Table I - Comparison of Various Baseline Characteristics

Characteristics Group I Group II
Number 30 30
Males (No.) 18 20
Age (mo) 52.3 (34.4) 62.9 (33.8)
Major Presenting Symptoms (%)
Breathlessness 100 100
Wheezing 93 93
Cough 100 100
Nocturnal exacerbation 70 53
Cyanosis 10 10
Fever 86 66
Duration of Presenting Symptoms (days)
Breathlessness 2.3 (1.4) 2.1 (1.1)
Wheezing 2.4 (1.5) 2.2 (1.2)
Cough 3.1 (1.6) 2.7 (1.3)
Cyanosis (hours) 7.3 (4.1) 6.3 (1.5)
Fever 4.0 (5.9) 2.4 (1.3)
Age at onset (mo) 17.7 (18.6) 19.1 (13.0)
Age at diagnosis (mo) 25.1 (20.2) 30.4 (22.2)
No. of attacks in last year 3.9 (2.6) 5.3 (3.2)
No. of hospitalization in last year 0.36 (0.6) 0.50 (0.6)
Days of hospitalization in last year 1.8 (3.3) 2.1 (3.1)
Time since last attack (mo) 3.9 (3.0) 2.6 (2.1)
Deteriorating trend of disease (%) 33.3 46.6
Values are depicted as means (SD) unless stated otherwise.
None of the differences between the two groups were statisticaly significant (p >0.05).

 

Table II - Sequential Comparison of Outcome Measures Evaluated

Parameter 0 min 20 min 40 min 60 min
  Group I Group II Group I Group II Group I Group II Group I Group II
Grading of Dyspena
Absent/Mild 0 0 5(16.6) 4(13.3) 16(53.3) 14(46.6) 24(80) 21(70)
Moderate 19(63.3) 15(50) 20(66.6) 18(60) 10(33.3) 14(46.6) 5(16.6) 9(30)
Severe 11(36.7) 15(50) 5(16.6) 8(26.7) 4(13.3) 2(6.6) 1(3.3) 0
Ability to Speak
Full sentences 11(36.7) 12(40) 18(60) 15(50.0) 22(73.3) 22(73.3) 24(80) 23(76.7)
Partial sentences/Phrases 12(40) 8(26.6) 7(23.3) 8(26.7) 5(16.7) 6(20) 5(16.6) 7(23.3)
Single words/Unable to speak 7(23.3) 10(33.3) 5(16.7) 7(23.3) 3(10) 2(6.7) 1(3.3) 0
Heart rate per minute 137.1(15.6) 139.5(21.8) 131.0(17.3) 132.1(20.1) 125.7(18.7) 127.0(20.6) 118.8(18.4) 121.3(20.4)
Respiratory rate per minute 56.2(9.2) 57.6(9.9) 53.1(9.1) 53.9(9.9) 49.3(8.1) 50.2(10.8) 44.2(8.9) 45.7(10.1)
Cyanosis 3(10) 5(16.6) 3(10) 5(16.6) 2(6.6)  1(3.3) 2(6.6) 0
Accessory Muscle Use
None/Mild 10(33.3) 7(23.3) 13(43.3) 16(53.3) 22(73.3) 22(73.3) 24(80) 24(80)
Moderate 12(40) 16(53.3) 11(36.7) 8(26.7) 4(13.3) 8(26.7) 6(20) 6(20)
Severe 8(26.7) 7(23.3) 6(20) 6(20) 4(13.3) 0 0 0
Breath Sounds
Normal 28(93.3) 28(93.3) 29(96.6) 29(96.6) 29(96.6) 30(100) 29(93.3) 30(100)
Decreased 2(6.7) 2(6.7) 1(3.3) 1(3.3) 1(3.3) 0 1(3.3) 0
Absent 0 0 0 0 0 0 1(3.3) 0
Rhonchi
Absent 0 0 1(3.3) 0 6(20) 4(13.3) 14(46.7) 10(33.3)
Expiratory 13(43.3) 8(26.6) 21(70) 22(73.3) 18(60) 21(70) 13(43.3) 19(63.3)
Inspiratory + Expiratory 17(56.6) 22(73.3) 8(26.7) 6(20) 5(16.7) 3(10) 1(3.3)  
PEFR (%) 61.5(12.0) 55.9(8.8)     73.0(10.7) 69.6(11.1)    
Pulsus Paradoxus (mm Hg) 14.9(8.8) 16.2(7.7) 13.2(8.4) 13.6(5.7) 11.4(7.8) 11.3(4.7) 9.8(6.4) 9.0(3.0)
Arterial Blood Gas
pH 7.43(0.03) 7.42(0.04)     7.42(0.04) 7.423(0.02)    
PCO2 (mm Hg) 34.12(5.07) 36.06(5.06)     32.16(4.17) 33.48(3.52)    
PO2 (mm Hg) 71.58(6.84) 69.95(8.35)     78.51(7.77) 78.05(6.72)    
BE (mmo1/L) 0.22(2.25) 0.73(1.44)     1(3.3) 0(0)    
O2 saturation (%) 92.05(3.11) 91.64(2.45)     94.49(3.58) 94.57(1.90)    
Values are depicted as means (SD) or numbers (%).
BE – Base excess.
PEFR – Peak expiratory flow rate.

Table III outlines the sequential cate-gorization of response in the two groups, as per the guidelines criteria. It is obvious that the MDI with indigenous spacer was equivalent in efficacy to MDI with commercial spacer for administration of salbutamol in acute asthma. At 60 minutes, the total number of patients showing good response was 47 (24 in Group I and 23 in Group II), while 12 patients (5 in Group I and 7 in Group II) had partial response. Only one patient out of the entire study group showed poor response at 60 minutes.

Table III - Response at Various Times

  Group I Group II Total
Severity of accute attack (at presentation)
Mild 12 (40) 6 (20) 18 (30)
Moderate 14 (46.7) 19 (63.3) 33 (55)
Severe 4 (13.3) 5 (16.7) 9 (15)
Response at 20 minutes
Good 13 (43.3) 10 (33.3) 23 (38.3)
Partial 14 (46.7) 17 (56.7) 31 (51.7)
Poor 3 (10) 3 (10) 6 (10)
Response at 40 minutes
Good 20 (66.6) 19 (63.3) 39 (65)
Partial 8 (26.6) 10 (33.3) 18 (30)
Poor 2 (6.6) 1 (3.3) 3 (5)
Response at 60 minutes
Good 24 (80) 23 (76.7) 47 (78.3)
Partial 5 (16.7) 7 (23.3) 12 (20)
Poor 1 (3.3) 0 1 (1.7)
Values depict Numbers (%).
None of the differences between the two groups were significant (p >0.05).

 Discussion

The study was conducted to assess the efficacy of an indigenous spacer in delivering aerozolized beta-2 agonist, in an effort to create a low cost and easily available alternative to an expensive commercial spacer device. With sample size taking the power of study as 80% at an alpha of 0.05 was sufficient to detect a difference in efficacy of 30% between the two methods of treatment.

The indigenous spacer used in the study was a tubular non-valved spacer device made of plastic (modified water bottle) with an approximate volume of 750 ml. The results of the study demonstrate that an indigenous spacer is as effective as a commercial spacer for delivery of beta-2 agonist in an acute exacerbation of asthma. Several previous studies have shown MDI with a commercial spacer is an equally efficacious alternative to a nebulizer(6-8). Thus, an indigenous spacer with MDI may be equally effective as a nebulizer. Recommending the use of a nebulizer as the method of choice for delivering aerosolized beta-2 agonists is a difficult proposition for a developing country like India because of economic constraints. Bowton et al.(8) showed a significant reduction in hospital costs following the substitution of MDI with spacer for nebulizer. An average nebulizer unit costs Rs. 3,000-7,000 and a commercial spacer costs Rs. 300-400. These costs may be prohibitive in the context of a country like ours. An indigenous spacer comparatively has negligible cost. Its cost effectiveness is at least 200 times that of a commercial spacer.

Different shapes of spacers have been compared for the efficacy. Newman et al.(11) showed that cone spacer increases total pulmonary deposition better than a tube spacer. Toogood et al.(17) also showed cone shaped spacers to be superior. On the other hand, Lulling and co-workers(18) failed to show any difference between pear and tube shaped spacers. There is a direct relationship between the size of spacer and amount of drug delivered leading to increased bronchodilation in children with asthma(19). A better response is obtained with volumes of ³750 ml irrespective of type of spacer.

Commercial spacers are provided with valves, which may have problems associated with it. Young children may not be able to open the valve of a commercial spacer, especially in a severe attack. A similar observation was made in this study too, where two of the younger patients with severe attack had difficulty in moving valve of the commercial spacer device. The valve of a commercial spacer tends to become sticky with prolonged use(20), preventing adequate delivery of drug. Levision et al.(21) have shown that non-valved spacers are equally effective. An indigenous spacer circumvents this problem. Small children may not be able to use the mouth piece of a commercial spacer and require a face mask, which entails extra expenditure and may not be easily available. Indigenous spacer overcomes this problem as the size of the mouth end opening can be customized to the child.

No studies have been done to recommend the best material for spacer. Ideal material for spacer would be one in which there would be minimal deposition of the drug on the walls of the spacer. Indigenous spacer devices used with MDI earlier have included coffee cups, plastic freezer bags, and plastic bottle, all of which have shown greater bronchodilator response than a MDI alone.

In conclusion, metered dose inhaler with improvised spacer device is equivalent in efficacy and a more cost effective alternative to metered dose inhaler with commercial spacer for administration of beta-2 agonist in acute asthma.

Contributors: GRS conceived the idea, supervised the data collection, helped in analysis and drafing the manuscript. He will act as guarantor for the paper. JP collected data, helped in analysis and prepared the intitial draft of the paper. VS helped in analysis and preparation of the manuscript.

Funding: Nil.
Competing interests:
None stated.

Key Messages

  • Indigenous spacer made from readily available 1 litre mineral water bottle was as effective as commercial spacer for delivery of b2 agonists in acute asthma.

  • Indigenous spacer can be used in very sick and young children as no effort is required to operate valve unlike in commercial spacer.

  • Indigenous spacer is much cheaper than commercial spacer, making it more suitable for use in resource starved developing countries.

 References
  1. National Heart, Lung and Blood Institute, National Asthma Education Program, Expert Panel Report. Guidelines for the diagnosis and management of asthma. J Allergy Clin Immuno 1991; 88: 425-534.

  2. Warner JO, Gotz M, Landau LI, Levision H, Milner AD, Pedersen S, et al. Management of asthma: A consensus statement. Arch Dis Child 1989; 64: 1065-1079.

  3. Guidelines for the management of asthma in adults. II. Acute severe asthma. Statement by the British Thoracic Society, Research Unit of the Royal College of Physicians of London, King’s Fund Centre, National Asthma Campaign, BMJ 1990; 301: 797-800.

  4. International Pediatric Asthma Consensus Group. Asthma: A follow up statement. Arch Dis Child 1992; 67: 240-248.

  5. Becker AB, Nelson NA, Simons PER. Inhaled salbutamol (albuterol) vs injected epinephrine in the treatment of acute asthma in children. J Pediatr 1983; 102: 456-469.

  6. Karem K, Levison H, Schuh S, O’Brodovich H, Reisman J, Bentur L, et al. Efficacy of albuterol administered by nebulizer versus spacer device in children with acute asthma. J Pediatr 1991; 123: 310-317.

  7. Batra V, Sethi GR, Sachdev HPS. Comparative efficacy of jet nebulizer and metered dose inhaler with spacer device in the treatment of acute asthma. Indian Pediatr 1997; 34: 497-503.

  8. Bowton DL, Goldsmith WM, Haponik EF. Substitution of metered dose inhalers for handheld nebulizers. Chest 1992; 101: 305-308.

  9. Canny GJ, Levison H. Aerosols: Therapeutic use and delivery in childhood asthma. Ann Allergy 1988; 60: 11-20.

  10. Sackner MA, Brown LK, Kinn CS. Basis of an improved metered aerosol delivery system. Chest 1981; 80 (Suppl): 915-918.

  11. Newman SP, Moren F, Pavia D, Little F, Clarke SW. Deposition of pressurized aerosols inhaled through extension devices. Am Rev Respir Dis 1981; 124: 317-320.

  12. Newman SP, Millar AB, Lennard Jones TR, Moren F, Clarke SW. Improvement of pressurized aerosol deposition with nebuhaler spacer device. Thorax 1984; 39: 935-941.

  13. Henry RL, Milner AD, Davies JG. Simple drug delivery system for use in young asthmatics. Br Med J 1983; 286: 2021.

  14. Yuksel B, Greenough A, Maconochie I. Effective bronchodilator treatment by a simple spacer device for wheezy premature infants. Arch Dis Child 1990; 65: 782-785.

  15. Lee H. Evans HE. Aerosol bag for administration of bronchodilators to young asthmatic children. Pediatrics 1984; 73: 230-232.

  16. Sibbald B, Horn MEC, Gregg I. A family study of genetic basis of asthma and wheezing bronchitis. Arch Dis Child 1980; 55: 354-357.

  17. Toogood JH, Jennings B, Baskerville J, Jahansson SA. Clinical use of spacer systems for corticosteroid inhalation therapy: A preliminary analysis. Eur J Respir Dis 1982; 63 (suppl. 12): 100-107.

  18. Lulling J, Deliviche JP, Hidinger KG, Prigmot J. Influence of different extension actuator tubes on the bronchodilation effect of a terbutaline sulfate aerosol. Eur J Resp Dis 1983; 64: 33-37.

  19. Reilly PA, Levison H, Worsley GH. Add on devices for delivery of aerosol drugs in children. In: International Workshop on Metered Dose inhaler. Ed. Epstein SW. Missisanga Ontario, Canada Astra Pharma-ceuticals Canada Ltd. 1984; pp 134-142.

  20. Cox ID, Wallis PJIM, Apps MCP. Potential limitations of conical spacer devices in severe asthma. Br Med J 1984; 288: 1044.

  21. Levison H, Reilly PA, Worsley GH, Spacing devices and metered dose inhalers in childhood asthma. J Pediatr 1985; 107: 664-666.

Home

Past Issue

About IP

About IAP

Feedback

Links

 Author Info.

  Subscription