Chest Physical Therapy for the Postoperative or Traumatic Injury Patient

COLLEEN M. KIGIN, MS

Techniques of chest physical therapy have been used since the early 1900s to decrease postoperative pulmonary complications. Through investigations since the 1950s, documentation as to the efficacy of chest physical therapy in actually reducing postoperative pulmonary complications has been published. However, the careful documentation of techniques employed (such as full Trendelenburg's position versus a modified position and vibration of particular force and fre­quency) has not been done. Also, because of an inability to specify the risk factors of postoperative pulmonary complications occurring in particular pa­tients or to qualitate the occurrence of these complications, it is difficult to establish what treatment is most efficacious. This article is a critical review of investigations to date with recommendations for further research stemming from this review.

Key Words: Respiratory dysfunction, Treatment techniques, Physical therapy.

Operative procedures and the care of trauma vic­tims have been recorded for centuries, with open chest surgery performed in Galen's time.1 As a result of advances over the past two centuries in mechanical ventilation, anesthesia, and infection control the es­timated number of surgical procedures in the United States in 1979 was 23,858,000. Included in this num­ber were 445,000 cholecystectomies, 166,000 open heart operations, and 813,000 respiratory procedures.2

The incidence of trauma has also been increasing in the United States and, in 1979, accounted for 65,000 hospital beds, and 22,000,000 bed days.3

Although operative procedures are vast in number, sophisticated in techniques, and remarkable in results, they continue to harbor significant risks. Respiratory failure is either a major cause or a major contributing factor in 50 percent of postoperative deaths.1 Treat­ment to prevent or modify respiratory complications has been a major focus of care for the operative patient. Since 1915, physical therapy has been widely used to prevent or reverse respiratory complications of surgery and trauma.4-9

The purpose of this paper is to review physical therapy used for postoperative or traumatic injury patients. This review will define and critically review postoperative pulmonary complications (PPC), and evaluative and therapeutic procedures used for the above types of patients. Needed investigations in chest physical therapy (CPT) will be proposed.

POSTOPERATIVE PULMONARY COMPLICATIONS

Anesthesia and medication result in some degree of respiratory depression in postoperative patients.10

Transient hypoxemia, first noted by Overholt in the 1930s, is a common finding in the early postoperative hours.11, 12 Supplemental oxygen, deep breathing, and coughing are routinely used to prevent PPC. Despite these preventive efforts, patients develop PPC (in­cluding atelectasis, which makes up 90 percent of PPC).1

Pasteur, in 1908, was the first to recognize atelec­tasis in the postoperative patient.13 Atelectasis, of Greek derivation meaning lack of expansion, is syn-onomous with alveolar collapse. Palmer stated, in 1952, that atelectasis was the most common PPC and it remains so today.14, 15

The primary causes of atelectasis include hypoven­tilation caused by obstruction of airways by secre­tions, decreased activity of the respiratory muscles, and decreased expiratory reserve volume.15 Preoper­ative medications, anesthetic agents, and drugs given in the intraoperative period decrease lung compli­ance, which contributes to diminished lung volume and atelectasis.16 Because surgery of the extremities results in fewer PPC than do abdominal and thoracic procedures, it appears that anesthesia is not the pri­mary cause of postoperative atelectasis.17 Other fac­tors that may contribute to atelectasis include supple­mental oxygen delivered to a patient at low lung volumes,18 increased abdominal girth that restricts lung expansion,17, 19 and changes in negative pressure in the thorax.20

Miss Kigin is Director, Chest Physical Therapy and Co-Director, Respiratory Care, Department of Anesthesia, Massachusetts General Hospital, Boston, MA 02114 (USA).

1724 PHYSICAL THERAPY

Physiologic changes resulting from atelectasis in­clude increased alveolar surface tension caused by deficient amounts of surfactant in the atelectatic area.20, 21 Surfactant, produced by type II pneumo-cytes, improves lung compliance, which decreases the need for high inspiratory pressures.22 With persistent atelectasis and the subsequent decrease in surfactant, increased inspiratory pressures are needed to reinflate the atelectatic area.23 Although atelectasis is not an infective process, prolonged atelectasis and decreased mucociliary transport can result in bacterial infection, or pneumonia.17, 21 A summary of postoperative pathophysiologic changes outlined by Tisi is found in Table l.15

Other PPC, less common than atelectasis, are pneu­monia, aspiration, adult respiratory distress syn­drome, and pulmonary embolus.19

FACTORS CONTRIBUTING TO PPC

Tisi, in 1979, divided into four groups the factors contributing to PPC (Fig. 1).15 A patient with one or more of these factors is considered at high risk for developing PPC. Although the figure offers predis­posing characteristics, no criterion has 100 percent sensitivity. Peters noted, in 1980, that the diversity of criteria for high risk classification adds to the variety of conclusions from studies of PPC.24

A variety of signs and symptoms can identify PPC. Some authors choose only one criterion (radiogra­phy),6, 14 others choose a combination of factors (ra­diography, temperature changes, breath sound changes, and pulmonary function changes).5, 8, 25-32

These variable criteria for PPC result in widely dif­fering complication rates for similar patients. Table 2 summarizes the criteria and incidence of PPC.33

TREATMENT OF PPC

A variety of treatments has developed through the years, but as recently as 1980 there was no consensus of the superiority of any procedure for the nonintu-bated patient.24, 33 The literature offers no more defin­itive information for the intubated patient group than it does for the nonintubated. This article will provided discussion about investigations in both groups.

PREOPERATIVE EVALUATION

Advances in preoperative evaluation have helped decrease the incidence of PPC.15, 34-37 In addition to identifying high risk factors, the information from the patient history and preoperative testing may indicate either that surgery may proceed or that further pre­operative evaluation and treatment are necessary. Advances in preoperative evaluation have been es­pecially effective in recognizing and decreasing po-

TABLE 1 Postoperative Pathophysiologic Changes in the Lung

Factors Mea­sured

Lung Volume Type sur­

gery

Thoracic

Abdomi­nal

upper lower

Extrem­ity

Ventilatory Pattern

Gas Ex­change

TLC

↓

↓ ↓

no ∆

TV

↑ Po2

↓

Changea

VC

↓

↓(50-70%) ↓(5-40%)

no ∆

RR

↑ A-aPo2

↑

ERV

↓

↓(≈ 60%) ↓(≈ 25%)

no ∆

Compli­ance

↓

RV

↓

Sigh Mecha­

nism ↓

a TLC = total lung capacity. VC = vital capacity.

ERV = expiratory reserve volume. RV = residual volume. TV = tidal volume. RR = respiratory rate. Po2 = partial pressure of arterial oxygen.

A-aPo2 = alveolar to arterial oxygen gradient. ↑ = increase. ↓ = decrease,

no ∆ = no change.

tential respiratory complications in the patient with chronic lung disease and the patient undergoing tho­racic surgery.

Weighting of high risk factors has been attempted to identify preoperatively the patient likely to develop PPC.17 The results, however, were not conclusive.

L General Factors smoking history obesity age (>50)

II. Disease Related Factors history COPD including

emphysema and bronchitis history restrictive lung disease

including neuromuscular disease HI. Type Anesthesia (listed least risk to greatest)

general anesthesia spinal anesthesia

IV. Type Surgery (listed least risk to greatest) nonabdominal, nonthoraeic (<1%) lower abdominal thoracic upper abdominal (6-70%)

Fig. 1. Factors contributing to postoperative pulmonary complications.

Volume 61 / Number 12, December 1981 1725

TABLE 2a

Selected Studies on Frequency of Postoperative Pulmonary Complications

Investigator

King (25) Dripps and Dem-

ing (26) Palmer and Sel-

lick (14) CPT only group

Thoren (5) Control group

Anscombe (27) Browne and

Rockford (28)

Latimer et al (29) Bartlett et al (30)

Control group Craven et al (31) Hansen et al (32) Lyager et al (8)

Study Type

Pro­spec­tive

Study

+ +

+

+

+ 0

+ +

+ + +

Total No. Pa­tients

7,065 1,240

90

172

300 226

46 75

70 40 94

Patientsb

No. with Thoracic Surgery

(...) (...)

(...) 226

(...) (...)

(...) (...) (...)

No. with Upper

Abdomi­nal Sur­

gery

759 1,240

66

172

46 75

70 40 94

Therapyc

Preop CPT or Other

RT

0 +

0

? ?

? ?

+ + +

Preven­tive

Postop CPT or

Other RT

0 "Stir-up"

0

? ?

? "Stir-up"

+ + +

Diagnostic Criteriad

Clinical Signs, Symp­toms

+ +

+

+ +

+ +

+ +

(+)

Radi­ogra­phy

+ +

+ R

+ R

+ R + R

+ R + R

+ R + R + R

ABG

0 0

0

0 0

0 +

(+)

Inci­dence of PPC

(%)

9 (total) 27 (UAS)

6 43

42

49 51

76 25

60 75 47•

a Reprinted by permission of American Review of Respiratory Disease.33 b No study excluded patients with preoperative pulmonary disease. c Preop—preoperative; CPT—chest physical therapy; RT—respiratory therapy; Postop—postoperative; +—yes;

0—no. d ABG—arterial blood gases; PPC—postoperative pulmonary complications; UAS—upper abdominal surgery; R—

routine test in all patients, performed at least once; (+)—reported, but not used to calculate incidence; •—based on positive radiograph only.

Pulmonary function tests are often cited as an iden­tifying factor for potential PPC. Stein and associates, in 1962, found maximal expiratory flow rates to be the best correlate with respiratory complications.34

Levy and associates found that spirometry results were no more successful than a chest radiograph for predicting PPC.38 Levy's group also found that pul­monary function testing, routine physical examina­tion, and chest radiograph results, when used to­gether, identified preoperatively 80 percent of the patients at risk for PPC. Gracey, too, supported mul-tifactored evaluations that included pulmonary func­tion tests.37 He also recognized that despite categori­zation as high risk, individuals within that group would vary greatly.

CHEST PHYSICAL THERAPY

History

Chest physical therapy was first described by MacMahon in a 1915 article that described treatment of the postoperative and trauma patient.4 Mac-Mahon's techniques have been supplemented by new approaches and devices, but the stated goals remain

largely unchanged. Those goals were 1) enabling the collapsed lung to regain normal condition, 2) restor­ing the normal shape of the chest wall, 3) assisting the discharge of pus through lung inflation, and 4) improving general conditioning by exercise.

Chest physical therapy originated in Great Britain and is currently universally used. For example, arti­cles about CPT have been published in Germany,39, 40

France,41, 42 Russia,43 Japan,44 South Africa,45 and the Scandinavian countries.5, 6, 8, 9

This review of CPT for postoperative or traumatic injury patients will discuss breathing exercises, posi­tioning and bronchial drainage, manual techniques, coughing, suctioning, transcutaneous electrical nerve stimulation (TENS), and upper extremity mobility exercises and ambulation. For each topic, a brief rationale will precede the major discussion regarding efficacy of the treatment.

Breathing Exercises

Rationale

In 1908, Pasteur recognized lobar collapse follow­ing paralysis or temporary inhibition of muscular

1 7 2 6 PHYSICAL THERAPY

activity.13 The exercises used by MacMahon in an attempt to reverse atelectasis included movement of the upper extremities, lateral costal expansion, and thoracic expansion in the area of collapse.4

Efficacy

MacMahon promoted maximal inspiration with placement of the therapist's hands on the area of collapse.4 This technique continues to be used. The therapist provides stimulus to the area through tactile input, as well as stretch and resistance provided to the muscles of inspiration. This is done in conjunction with verbal commands to the patient to inspire to the fullest. Though this has been a long standing method of treatment, there is lack of standardization as to how much pressure or stretch; in what position one should offer this pressure or stretch; and also how much resistance to provide to the diaphragm or inter-costals once movement has been initiated. In review­ing literature on CPT for the postoperative patient, it is not even clear whether instructions to a patient are done with the use of manual assistance of the hands, or only through verbal encouragement or simple tac­tile proprioception of hand placement.

Neuromuscular facilitation of respiration for the postoperative patient has been rarely discussed since 1915.4 Bethune, in 1975, outlined an approach to facilitate respiration in the unconscious adult, using principles suggested by Rood.46 Using cocontraction of the abdominal muscles, pressure on the upper thoracic vertebrae, and stretch of the intercostal mus­cles, Bethune visibly noted in her patients deeper respiration, change in respiratory pattern, and an apparent increase in consciousness. I have observed similar findings when using these techniques for the postoperative patient. Further study is needed in this area of care.

More definitive studies of CPT began in 1954 when Thoren examined the incidence of PPC in 343 pa­tients who had cholecystectomies.5 Patients were as­signed to one of three groups: 1) preoperative and postoperative CPT, 2) postoperative CPT, and 3) no CPT. The CPT included breathing exercises with the patient sitting and sidelying and encouragement to cough, as described by Ingvarsson.9 The 12 percent PPC incidence in group 1 was lowest. Groups 2 and 3 had complication rates of 27.1 percent and 41.9 percent, respectively.5 These findings were confirmed by a similar study in 1956 by Wiklander and Norlin.6

Both studies used radiographic evidence of atelectasis as the criterion for PPC. Although the treatment is described for each study, it is difficult to ascertain whether percussion and vibration were used also.

In 1977, Vraciu and Vraciu studied the effects of breathing exercises taught by physical therapists to 40

postoperative cardiac surgery patients.7 The experi­mental group received the breathing exercises in ad­dition to the incentive spirometry, ultrasonic nebuli-zation, and routine instructions by nurses in deep breathing and coughing provided for the control groups A 38 percent PPC rate was found for the control group. The experimental group, whose sub­jects were instructed and monitored by physical ther­apists, had only a 16 percent complication rate. The PPC were defined as temperature higher than 38.5° C, radiographic changes, or abnormal breath sounds. This study indicates a need to standardize the method of deep breathing in a manner different from that routinely taught by nurses.

Adjuncts to Breathing Exercises

Blow bottles, intermittent positive pressure breathing (IPPB), and incentive spirometry (IS) have been used in an effort to decrease PPC.33, 47-50 Blow bottles and IPPB have not been upheld as efficacious treat­ments.33 Incentive spirometry currently is being in­vestigated heavily. The efficacy of IS to date has varied when compared to other techniques including C P T 8, 5 1 - 5 3

In 1966, Ward supported the necessity of hourly deep breathing to prevent or reverse atelectasis.54

Pontoppidan, in 1980, speculated that this hourly requirement for deep breaths might account for the ineffectiveness of IPPB in preventing atelectasis when delivered every 4 hours.33

Bartlett and associates, in 1971, had patients per­form a yawn maneuver postoperatively using the incentive spirometer.55 The group of patients using the yawn had an increase in mean arterial partial pressure of oxygen (Pao2) when compared to a control group. The incentive spirometer is a device that pro­vides visual feedback in terms of volumetric success as a patient performs a deep breath. The value of a sustained maximal inspiration is also brought to the forefront through work by Bartlett. This very princi­ple was in fact mentioned by MacMahon in 1915.

Craven and colleagues subsequently compared IS and CPT in 70 subjects who had upper abdominal surgery.51 Both the IS and CPT groups received train­ing before and after surgery. The IS group was en­couraged to use the device 10 times each hour for the first 5 postoperative days. The CPT group was treated at least twice each day. The IS group had a PPC rate of 37 percent and the CPT group had a rate of 63 percent. Craven stated that the CPT regimen failed to emphasize deep breathing as had been suggested by Thoren.5

In 1978, Hedstrand and associates compared ver­bally and manually assisted breathing exercises to three breathing devices—IS, IPPB, and paper coil

Volume 61 / Number 12, December 1981 1727

Fig. 2. Example of modified drainage position for right middle lobe. Patient receiving hyperinflation on 100 per­cent oxygen and vibration.

rebreathing tube.52 In the groups using the devices, a mean increase in transcutaneous Pao2 (Tcpo2) of 3.0 to 3.5 mmHg was noted, with no difference among the devices. The group receiving breathing exercises had a mean increase in Tcpo2 of 7.0 mmHg. This study showed the importance of manually facilitated deep breathing. I suggest that manual assistance fa­cilitates inspiration by initiation of a stretch reflex within the diaphragm or intercostal muscles.

Lyager and colleagues, in 1979, studied IS as an adjunct to CPT for upper abdominal surgery pa­tients.8 They found no change in the PPC rate with the addition of IS and attributed the results to an aggressive physical therapy program similar to that of Thoren.5

In 1979, Heisterberg and co-workers compared blow bottles to CPT in 98 patients who had abdomi­nal surgery. Although they found no difference be­tween the treatments, the rate of PPC was 30 percent for each. Others have questioned the efficacy and safety of blow bottles and suggested that they not be used.33

Other recognized aids to ventilation for the post­operative patient that will not be discussed in detail are appropriate pain medication and nerve blocks.56, 57

Conclusions

There is a need for studies that carefully define breathing exercises and their benefits to postoperative patients. Previous studies are difficult to compare, but those emphasizing specific breathing exercises result in a low PPC rate. Changes in ventilation resulting from manual stretch, resistance, and other techniques of neuromuscular facilitation have yet to be docu­mented. The addition to a CPT regimen of adjunctive devices including IS, IPPB, and blow bottles adds little to further decrease the PPC rate.

Positioning, Bronchial Drainage, and Manual Techniques

Little research has been done to study the efficacy or adverse reactions of either bronchial drainage or man­ual techniques. However, clinically it is observed day after day that using a full Trendelenburg's position may cause a transient drop in blood pressure in a patient, but using a modified position allows the treatment to proceed. A situation that also can be reversed easily is one of a patient showing transient arrhythmias with the use of percussion that do not appear when the therapist switches to vibration. Even though research is scanty as to the actual positive or adverse effects of each of these techniques, this article will differentiate, when possible, between position change, bronchial drainage, and manual techniques.

Positioning and Bronchial Drainage

Rationale

Many authors have stated that position change for bronchial drainage facilitates mucus flow through the effects of gravity.58-62 When patients cannot tolerate the full Trendelenburg's position, modified drainage positions have been suggested (Fig. 2).7, 63-65

Frequently changing the position of the postoper­ative or traumatic injury patient has been advised to decrease the risk of atelectasis. Because most air flow goes to the most dependent lung region,66 sitting upright improves flow to the lung bases and side lying increases airflow to the dependent lung. Also, im­proved and more efficient diaphragmatic excursion occurs on the side of the dependent lung.67 With time, the pressure of the bed against the chest wall begins to restrict movement of the dependent portion of the thorax. Additionally, the bedridden patient does not change his ventilatory pattern as frequently as the alert, ambulatory patient. These physical factors plus the detrimental effects on mucociliary transport of general anesthesia will combine to cause atelectasis in the dependent lung area.

Efficacy

Research to verify mucus flow with the patient in full or modified positions has been scanty. Sackner, in 1978, reported that abnormal mucus moved cau-dally through the trachea with the patient upright, and cranially with the patient's head down.68 Other attempts to document the efficacy of positioning have been made, usually by recording Pao2 changes.69-74

Studies of physiologic changes concomitant with position change have concentrated on side lying and prone positions. These studies found an increase in Pao2 with the healthy lung dependent in patients with

1 7 2 8 PHYSICAL THERAPY

unilateral lung disease.69, 70 Patients with acute respi­ratory disease had an increase in Pao2 when moved from supine to prone.73 These findings should be reviewed in relation to full positioning and modified positioning when treating the postoperative or trau­matic injury patient.

Measuring arterial blood gases postoperatively in obese patients, Vaughan and Wise found a statisti­cally significant increase in Pao2 when the supine patient was repositioned semirecumbent.71 This change occurred because vital capacity is less in the supine position than when upright. This finding sup­ports moving patients not only from side to side, but to an upright position as soon after surgery as is feasible.

Connors and associates, in 1980, studied 22 acutely ill nonsurgical patients using a full Trendelenburg's side lying position.75 The patients also received per­cussion. Connors' group recorded heart rate, respira­tory rate, blood pressure, and arterial blood gases after the patient reclined in a 30 degree head up position for 10 minutes. Measurements were repeated after the patient had been side lying with the foot of the bed raised 12 inches and the diseased lung supe­rior for at least 5 minutes. These two measurements were followed by a third set taken after percussion and vibration. Although not the primary purpose of this study, the results showed that most patients had little change in Pao2 after position change. However, two mechanically ventilated patients had a significant drop in Pao2 after either the position change or the position change followed by percussion and vibration. This decrease in Pao2 was reversed with a fraction of inspired oxygen (Fro2) of 100 percent.

In 1978, Mackenzie and associates studied 47 trauma victims with respiratory failure.76 Twenty-six were treated while side lying in full Trendelenburg's position, and 16 were treated in one of three modified positions—supine, upright, or side lying. Treatment included percussion and vibration without hyperin­flation. Gormezano and Brainthwaite had previously advocated hyperinflation with manual chest compres­sion.64 Mackenzie and associates found no significant change in Pao2 in patients treated in either Trende­lenburg's or modified positions. The mean treatment time for each patient was 51 minutes. The mean Fro2 was 42 percent. Mackenzie speculated that differences in techniques in their study prevented the fall in Pao2 reported in other studies.76 However, in our clinic, bag squeezing is used routinely without apparent adverse effects while permitting efficient secretion removal.

Changes in both cardiac output and intracranial pressure have been measured during CPT.63, 77, 78 The two measurements noted above have been determined during a regimen of CPT that includes positioning and manual techniques. No definitive studies have

attempted to differentiate the various techniques and their effect on cardiac output or intracranial pressure. Clinical observation or monitoring of these physio­logic factors allows treatment for patients with cardiac or neurologic disease to be done by modifying the position or technique as necessary.

Conclusions

The gravity dependent portion of the lung receives the greatest airflow except when long periods are spent in one position and during mechanical venti­lation. Placing the acutely ill patient prone may in­crease the Pao2 without changing the Fio2. Cardiac output and intracranial pressure may also vary with position changes. These measurements must be closely monitored. Modified positions are often tol­erated by patients with adverse reactions to full po­sitioning.

Position change to facilitate mucus flow is unnec­essary for patients with normal mucociliary functions. Patients may lose their mucociliary clearance post­operatively or during mechanical ventilation. Chang­ing position in these situations will facilitate secretion removal and decrease secretion pooling.

Arterial Pao2 may vary with position changes. The findings have been neither consistent nor definitive for postoperative patients and further study is needed.

Manual Techniques

Rationale

Although manual techniques are universally em­ployed, their historical development is unclear. Man­ual percussion or clapping on the chest is thought to loosen secretions. Frownfelter states that this loosen­ing is achieved by mechanical waves produced by the percussing hand.60 Vibration may be used alone or in conjunction with percussion. Ingwersen states that vibration, used with a forced expiratory maneuver called "huffing," moves secretions toward the tra­chea.61 Vibration is reportedly a more comfortable alternative to percussion for use on the patient with pain. Shaking is a more vigorous form of vibration used when secretions are thick and tenacious.

Efficacy

Research to document the specific effects on the postoperative patient of percussion, vibration, and shaking of the chest wall has not been reported. Studies have included the combined effects of manual techniques with bronchial drainage and breathing exercises. There was no agreement regarding the du­ration and frequency of manual techniques—reported durations ranged from 764 to 11076 minutes and one

Volume 61 / Number 12. December 1981 1729

frequency for vibration was 20 cycles a second.64 Nor was there consensus of the force or rapidity with which each technique should be applied to the thorax.

Studies using manual techniques for medical pa­tients showed the techniques successful in removing secretions.79-81 Success was defined as sputum pro­duction and improvement of regional ventilation. Success of the manual techniques for the postopera­tive patient can be only inferred from studies of PPC rates, denoted in the postoperative groups by temperature change, radiographic improvement, breath sound increases, and blood gas enhance­ment.5-8, 26, 31, 32

Clinically, investigators have seen through a bron­choscope rapid clearance of secretions during manual percussion and vibration to the thorax (personal com­munication, D. Kanarek, MD, May 1981). In our institution it is common practice for chest physical therapists to provide positioning, percussion, vibra­tion, and shaking to facilitate secretion removal dur­ing bronchoscopies. I have observed through a bron­choscope secretion flow during percussion and vibra­tion to dogs (unpublished research). Percussion on each dog's thorax resulted in a splattering of plugs of propyliodone previously instilled into the trachea. Vibration resulted in a more directional flow of the propyliodone without a breaking apart of the bolus. These findings warrant further study.

There have been no studies to evaluate or compare mechanical vibrators or percussors with manual tech­niques in the postoperative patient.

Other variables studied during bronchial drainage, percussion, and vibration have included cardiac out­put,63, 77 cardiac arrhythmias,82 intracranial pressure,78

gas distribution,79 and lung compliance.83 There is no current consensus regarding physiologic changes ac­companying individual techniques including full or modified positioning, percussion, vibration, and shak­ing.

Bronchial Drainage with Manual Techniques

Efficacy

Many investigators have found CPT successful in reversing lobar atelectasis in postoperative, traumatic injury, and nonsurgical patients.76, 82-85 Marinni and associates, in 1979, compared bronchoscopy to a reg­imen including several respiratory techniques.84 This regimen included deep breathing with IS every four hours, cough or suction, bronchodilator administra­tion, and bronchial drainage with chest percussion. This well-designed study found no difference between the two therapeutic approaches in restoring lung vol­ume lost to atelectasis. The mean volume restoration was 38 percent. Mackenzie and associates also found

significant mean resolution in atelectasis of 68 percent following CPT.76

Marinni and associates used percussion and drain­age for five minutes to each area of atelectasis.84

Mackenzie and associates76 and Ciesla and col­leagues,85 in separate studies, used full positioning and vigorously applied manual techniques. Ciesla's group found dramatic increases in Pao2—ranging from 61 to 150 mmHg—in patients with hypotension who were also receiving mechanical ventilation with high levels of positive end expiratory pressure (PEEP). Hypotension and PEEP are often considered as contraindications for CPT by other investigators.

In 1969, Laws and co-workers studied six patients receiving CPT in right and left side lying positions.77

Treatment included vibration and an artificial cough produced by a deep breath with maximum vibratory compression during exhalation. They found no change in arterial blood gases or alveolar-arterial oxygen difference, but cardiac output varied by 50 percent in either direction in several patients.

Lord and associates studied patients who received CPT in the recovery room following cholycystec-tomy.86 Patients were treated in full Trendelenburg's position with percussion and vibration. An abrupt rise in Pao2 was noted in the CPT group when compared with a control group. FIo2 was not recorded in the study.

Gormezano and Brainthwaite, in 1972, studied 42 mechanically ventilated patients following cardiac surgery or respiratory failure.64 The CPT included hyperinflation, manual chest compression, and suc­tioning. The patients were treated in either supine or side-to-side positions. The authors found no signifi­cant change in Pao2 except in patients with cardio­vascular complications. The drop in Pao2 in this group with complications occurred at 5 and 15 min­utes after treatment, but Pao2 had returned to pre-treatment values by 30 minutes after treatment. These authors were among the few who clearly defined duration of treatment (7 to 20 minutes) and frequency of chest compression (20 Hz).

Tyler and associates reported on the effects upon Pao2 of CPT for critically ill patients.87 Although they noted a mean decrease in Pao2 during CPT, a regres­sion analysis found that patients with low initial Pao2

had little or no further decrease during treatment. Hence, Tyler's group concluded that CPT should not be denied patients with low Pao2.

Conclusions

The above data strongly support using CPT for patients with segmental or lobar atelectasis and large amounts of retained secretion. The Pao2 can be main­tained during treatment and will improve following treatment even in acutely ill patients. The preventive

1 7 3 0 PHYSICAL THERAPY

value of percussion, vibration, and shaking is un­known for the patient with small amounts of sputum.

Air flow alterations resulting from position change, deep breathing, sighing, and manual techniques must be clarified. By carefully recording specific techniques and their effects on specific types of patients, inves­tigators can fully verify the indications and contrain­dications for the techniques. The optimal frequency, force, and duration of manual techniques also must be ascertained for specific types of patients.

Adjuncts to Bronchial Drainage and Manual Techniques

Mechanical aids to inspiration and the importance of adequate oxygenation have been discussed previ­ously. Administration of bland aerosols and proper humidification to aid secretion clearance have re­cently been reviewed.88

Winning and associates studied bronchodilators used in conjunction with CPT.89 This study is of interest in that the effects of physical therapy plus bronchodilators were studied in conjunction with the patient receiving an FIO2 of 100 percent for five minutes before, during, and after treatment. In a previous paper90 the authors noted that they were unable to document a deterioration in arterial oxy­genation after physical therapy as found by previous investigators. In this study they found that there were no significant changes in arterial oxygen tension after treatment, but that alveolar pressure fell significantly indicating a definite improvement in pulmonary com­pliance.

Cough

Rationale

A cough is a rapid expulsion of air from the lungs elicited either reflexly or voluntarily. For an effective cough, the lungs must be inflated well and the vocal cords must close. These two events are quickly fol­lowed by strong contraction of the abdominal muscles which, in conjunction with elastic recoil of the lung tissue, results in a rapid expulsion of air through the suddenly reopened vocal cords.91, 92 Coughing effec­tiveness may be impaired postoperatively because of decreased inspiratory volume caused by poor dia­phragmatic excursion and weak contraction of the abdominal muscles.19 Byrd and Burns studied cough dynamics in 24 adult males.93 Immediately following thoracotomy the subjects could develop a cough with a mean force of only 29 percent of the preoperative value. A 50 percent diminution in force remained one week after surgery. The authors stated that pain was probably the primary factor causing the changes in cough.

The patient with an endotracheal intubation will also experience submaximal airflows during coughing

because of the increased resistance to airflow resulting from the endotracheal tube.94 It is important, there­fore, to inflate adequately the intubated patient's lungs by using a ventilator or by bag squeezing before expecting him to cough.

Efficacy

Yamazaki and colleagues, in 1980, determined cough strength in thoracotomy patients by using a balloon catheter to measure intrapleural pressure dur­ing coughing.95 They found higher cough pressures with the patient sitting than with the patient supine. They also found significant increases in cough pres­sures when a therapist or nurse provided manual compression during the patient's cough. Compression of the chest wall with the patient sitting was the most effective method, but compression of the abdominal wall with the patient supine also was effective.

Others have studied the effects of position on coughing. Curry and Van Eeden studied air flow during coughing in nine normal subjects in positions ranging from semiprone to upright.96 They found the highest flow rates with the patient upright. In 1980, Starr studied 20 subjects who had undergone choly-cystectomy.97 Included in the preoperative CPT was cough instruction. Four standard positions for cough­ing were taught and their effectiveness evaluated. The order of positions was randomized and included right and left side lying, semi-Fowler's, and upright. Be­tween 4 and 6 hours postoperatively, and again after 24 hours, flow rates were measured in each position while the patients coughed. The upright position re­sulted in the patient achieving a greater flow rate than any other position. There were no differences among the side lying and semi-Fowler's positions.

Huffing—the expulsion of air through an open glottis—has been advocated as a less painful and less stressful method of clearing the airways of secretions. This technique has been studied in subjects with asthma, chronic obstructive lung disease, and cystic fibrosis.98"100 These three studies have concluded that huffing is an effective means of mobilizing secretions and may provide better stabilization of the airways than does coughing. I have found huffing beneficial for the surgical patient having difficulty in coughing, but no published data support its use following sur­gery.

Conclusions

The effectiveness of a cough at removing secretions has been documented. Adequate inspiratory volume and forceful contraction of the abdominal muscles are necessary for effective coughing. The upright position permits a stronger cough than side lying or supine positions. Support and compression of the patient's thorax or abdomen may enhance the cough-

Volume 61 / Number 12, December 1981 1731

Fig. 3. Optimum position for coughing, with option of therapist using chest compression or vibration to facilitate secretion removal.

ing effort (Fig. 3). Huffing may be a good alternative to coughing but its effectiveness for the surgical pa­tient needs further study.

Tracheobronchial Suctioning

Rationale

Tracheobronchial suctioning uses a catheter at­tached to a vacuum source to aspirate secretions from the airways of a patient unable to cough. Suctioning is widely discussed in the CPT and surgical literature and is an important alternative to coughing during CPT.

Efficacy and Complications

The effectiveness of tracheobronchial suctioning appears to have face validity; secretions that cannot be cleared voluntarily are obtained easily through the aspirating catheter. The irritative effect on the tra­cheal mucosa from a suction catheter may stimulate an effective cough without vacuum aspiration. During suctioning, a patient with thick tenacious secretions and a cough that cannot be stimulated even with the catheter in the trachea may benefit from vibration, which moves the secretions toward the trachea (Fig. 4).

Many studies have examined the possible compli­cations of suctioning the airway.101-107 The most com­mon problems are damage to the tracheal mucosa and abrupt drops in Pao2. The drop in Pao2 occurs during both nasotracheal suctioning and aspiration through an endotracheal tube or tracheostomy. Adlkofer and Powaser studied the effects on arterial blood gases of nasotracheal suctioning after cardiac

surgery in 64 subjects. 106 Patients who received sup­plemental oxygen before suctioning had no signifi­cant fall in Pao2. Patients suctioned without supple­mental oxygen experienced a decrease in Pao2. Hence, adequate oxygenation is recommended before and after suctioning the airway. In addition to supple­menting the FIo2, proper vacuum levels and sterile technique will minimize complications from suction­ing.

Conclusions

Adequate preoxygenation and postoxygenation, minimal duration of suctioning, and proper vacuum levels are important elements of proper suctioning. Patients who receive supplemental oxygen before suc­tioning do not experience the dramatic fall in Po2 levels that occurs without this supplement. Many clinicians use a suction catheter to stimulate a cough in the nonintubated patient who is unable to clear secretions spontaneously.

Transcutaneous Electrical Nerve Stimulation

Rationale

Transcutaneous electrical nerve stimulation (TENS) is a frequently used modality to treat chronic pain. It was first developed in response to the gate-control theory of pain proposed by Melzak and Wall in 1965.108

Efficacy

Hymes and associates, in 1974, used TENS for postoperative pain in 213 patients.109 Pain relief was evaluated by examining the frequency with which analgesics were used, length of stay in the intensive care unit, incidence of atelectasis and ileus, and shoul­der mobility. The authors found a significant reduc­tion in atelectasis and an increase in the mean eleva­tion of the humerus from 90 degrees to 154 degrees following 15 minutes of TENS.

VanderArk and McGrath, in 1975, studied TENS in 100 patients who had abdominal or thoracic op­erations.110 Patients were randomly assigned to a con­trol or treatment group. Thirty-two of 39 subjects in the control group had no pain relief. In the treatment group, 47 of 61 patients reported relief, with maxi­mum improvement noted after the initial treatment. No difference in the incidence of atelectasis or ileus was reported.

Cooperman and colleagues, in 1977, randomly as­signed to a control group or treatment group 50 patients scheduled for major abdominal surgery.111

Pain relief was recorded as excellent, good, or poor.

1732 PHYSICAL THERAPY

In the control group, 12 percent had excellent relief, 21 percent had good relief, and 67 percent had poor relief. In the treatment group 35 percent had excellent results, 42 percent had good results, and 23 percent had poor results. There was no difference between the control and treatment groups in the incidence of atelectasis, pneumonia, or ileus.

Stratton and Smith, in 1980, postoperatively mea­sured forced vital capacity on the premise that mea­surement of pain was too subjective.112 After thora­cotomy, 21 patients were randomly assigned to a control group or TENS treatment group. Forced vital capacity was significantly greater for subjects in the TENS group. No incidence of complications was recorded, and no other data were provided.

Conclusions

Transcutaneous electrical nerve stimulation ap­pears to be an effective method to decrease symptoms of postoperative pain. It is unclear if a concomitant decrease in PPC rate accompanies the pain relief.

Mobility and Ambulation

Rationale

Early postoperative mobility and ambulation have become routine. This activity helps decrease PPC rate and lowers the incidence of pulmonary embo­lism.19, 113 The CPT literature describes the necessity of range-of-motion exercises for extremities near the incision site.4, 59, 60, 62 Range-of-motion exercises will prevent or retard loss of musculoskeletal function in joints affected by incisional pain or splinting.

Efficacy

Studies to date have documented a decrease in the incidence of pulmonary embolism in patients who are ambulated early as well as in those who receive passive and active lower extremity exercises.113, 114

Physical therapists have proposed exercises to maintain or restore motion to the upper extremity on the side of a thoracotomy site.4, 51, 62, 64, 111 Patients without this exercise program often lose motion in the shoulder and may develop a "frozen" shoulder. I have noted this problem particularly in children. Immediate postoperative range-of-motion exercises, posture correction, and use of TENS can prevent musculoskeletal dysfunction following thoracotomy.

Conclusions

Early mobility decreases pulmonary embolism when used in conjunction with other prophylactic

treatments. Early range of motion, when indicated for an extremity near an incision site, decreases mus­culoskeletal changes resulting from immobilization.

PROPOSED AREAS FOR INVESTIGATION

Although the value of CPT for the postoperative patient has been demonstrated by several well-de­signed studies, including those by Thoren, Wiklander and Norlin, and Lyager and associates, further re­search is needed.5, 6, 8

The benefits and complications caused by position change should be determined for each major type of patient. The addition to a physical therapy regimen of mechanical devices, such as IS and IPPB, should be studied. Will these costly devices add to the bene­fits of an aggressive CPT regimen?

Controlled studies of secretion removal techniques for the postoperative and traumatic injury patients should be a priority. Determination of the separate and combined benefits of positioning for bronchial drainage, manual techniques, coughing, and huffing is needed. New studies should measure the force, frequency, and duration of both percussion and vi­bration and determine their effects upon each type of PPC. Also, clarifying the contraindications for and complications of these techniques would be valuable. Although individual techniques may be contraindi-cated in certain instances, surely a modification of that technique or substitution of another modality can offer therapeutic benefit.

Investigation of the efficacy of TENS for decreas­ing PPC rates should continue. The type and fre­quency of upper extremity mobility exercises also warrant documentation. And simple lower extremity mobility exercises need to receive further study.

Fig. 4. Patient being suctioned (sterile technique) as therapist continues to vibrate left lingula.

Volume 61 / Number 12, December 1981 1733

Postoperative pulmonary complications remain the most prevalent problem for the surgical patient. The number of operative procedures continues to increase annually, as does the cost of hospital care. By inves­

tigators determining optimal treatment and preven­tive measures for PPC, including the efficacy of CPT, the surgical patient can be more effectively and more economically treated by the practitioners.

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