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Lower extremity ischemia associated with use of military antishock trousers
CASE REPORT MAST, complication; MAST, ischemia; military antishock trousers, complication, ischemia
Lower Extremity Ischemia Associated with Use of Military Antishock Trousers A 58-year-old m a n was admitted to a c o m m u n i t y hospital following an overdose of nifedipine. Military antishock trousers (MAST) were applied to combat severe hypotension. Blood pressure was restored to 110/50 m m Hg three hours after admission, but the patient remained comatose. Subsequent to MAST garment removal, isehemia of both legs and scrotum was observed; at surgery, both iliofemoral systems were occluded from the aortic bifurcation to the feet. The patient never regained consciousness and died from recurrent ventricular tachycardia. The possible contributing role of the M A S T garment in producing lower e x t r e m i t y ischemia is discussed. [Frampton MW: Lower extremity ischemia associated with use of military antishock trousers. Ann Emerg Med December 1984;13:1155-1157.]
INTRODUCTION
Mark W Frampton, MD Sodus, New York From Myers Community Hospital, Sodus, New York Received for publication November 8, 1983. Revisions received December 19, 1983, and April 2, 1984. Accepted for publication April 11, 1984. Address for reprints: Mark W Frampton, MD, 4418 Ridge Road East, Wiliiamson, New York 14589.
M i l i t a r y antishock trousers (MAST) have gamed increasing acceptance in the t r e a t m e n t of hypotensive states due to t r a u m a or hemorrhage.], 2 External compression of the extremities by the air-inflatable garment raises blood pressure; while traditionally this has been thought to result from volume redistribution, recent evidence indicates the predominant m e c h a n i s m of action m a y be an increase in peripheral resistance.3, 4 Successful use in acute t r a u m a has led to recommendations for expanding their application to nontraumatic conditions as w e l l s Proper use of the garment has been thought to be safe. Literature accomp a n y i n g the e q u i p m e n t (The M A S T Manual, David Clark Co, Worcester, /VIA) m e n t i o n s "frank p u l m o n a r y edema" as the only contraindication. There have occurred, however, reports of lower extremity ischemia following use of the M A S T unit.6, 7 Presented is a case report that raises further questions regarding the safety of pressurized garments in critically ill patients.
CASE REPORT A 58-year-old m a n arrived in the emergency department of a c o m m u n i t y hospital 1V2 hours after ingesting approximately 1 g nifedipine in a suicide attempt. The patient had a history of a diaphragmatic wall myocardial infarction several years previously and subsequent stable angina pectoris. On arrival in the emergency d e p a r t m e n t he was conscious; blood pressure was 60/0 m m Hg; pulse, 120; and respirations, 24. Electrocardiogram (ECG) showed sinus r h y t h m w i t h an inferior scar; central venous pressure was zero. A n intravenous infusion w i t h normal saline was begun, but shortly thereafter b l o o d p r e s s u r e b e c a m e u n o b t a i n a b l e and he suffered loss of consciousness and a respiratory arrest. Heart rate dropped to 35. The patient was intubated; atropine 0.5 mg was administered 1V with increase in the pulse rate to 80. The M A S T garment was applied one hour after arrival and was inflated to less than m a x i m a l pressure (a pressure-monitoring assembly was not available); the abdominal portion of the garment was not inflated. A t the same time 1 g calcium chloride was administered. These measures resulted in a brief rise in the blood pressure to 132/100 m m Hg w i t h i n ten minutes, but 15 m i n u t e s later it was again 60/0 m m Hg. Central venous pressure remained at 0 despite administration of 3,000 cc isotonic saline and 100 mEq sodium bicarbonate. A n additional gram of calcium chloride and continued infusion of saline
13:12 December 1984
Annals of Emergency Medicine
1155/119
ISCHEMIA WITH MAST Frampton
brought the blood pressure up to 80/60 w i t h i n 65 minutes, and to 110/50 m m Hg after another hour. During this time the patient received a total of 5,000 cc saline with potassium chloride and sodium bicarbonate. As blood pressure returned, a femoral pulse was palpable on the left, but was not palpable on the right. The patient remained unconscious with intermittent seizure activity despite subsequent blood pressures ranging from 100/60 m m Hg to 124/80 m m Hg. At 10:00 PM the attending physician gave orders for gradual deflation and removal of the MAST garment over two hours. Blood pressure remained stable during removal of the garment. At 7:00 AM, 14 hours after admission, examination of the lower extremities revealed cool pallor of both legs to the midpelvis, w i t h deep cyanosis of the scrotum. Muscles were stiff and indurated, consistent with hours of total ischemia. Transfer to a central hospital was accomplished, and emergency bilateral femoral embolectomy was performed. At surgery both iliofemoral systems from the aortic bifurcation to the feet were found to be thrombosed. Casts of the iliac arterial system, superficial femoral artery system, and the profunda femoris arteries were removed using a Fogarty catheter. The catheter could not be passed below the popliteal artery on the left side. The patient did not regain consciousness, and died several hours later of refractory ventricular tachycardia.
DISCUSSION "Military antishock trousers" first came into use as a battlefield aid to combat the effects of shock from blood loss until transport to a treatment area could be achieved. Their use in the prehospital accident scene was an outgrowth of this application. Reports of successful use 1 have led to suggestions that the garment may be helpful in other types of shock, including gastrointestinal bleeding, per i p a r t u m bleeding, a n a p h y l a c t i c shock, diabetic ketoacidosis, and drug overdose. 2 One limited study even suggests a use in treating cardiogenic shock, s which has been criticized. 8 The garment also has been used in an attempt to increase effective blood pressure in patients undergoing external cardiac compression; 9 a rise in b l o o d p r e s s u r e of 15 m m was 120/1156
achieved, but there was no other indication of clinical benefit. Reports of adverse effects of MAST use have appeared in the literature. Use in a case of postpartum hemorrhage ended in fatality, found to be the result of air embolus. The authors concluded, " . . . use of this garment may have contributed to this patient's death. "10 Maull et al 6 reported the development of lower extremity compartment syndrome leading to amputation related to prolonged MAST use (48 hours). This occurred despite careful Doppler monitoring of pulses and m e a s u r e m e n t of c o m p a r t m e n t pressures during the course of treatment. In a letter Goodenberger 7 reported occlusion of both femoral arteries by long clots after MAST use in a patient with a leaking aortic aneurysm. An experimental indication of adverse effects came in 1969 f r o m Wangensteen et al, u who applied pressure bladders to dogs after sudden removal of 30% of blood volume. Although blood pressure responded immediately to pressure application, it later fell again, and treated animals actually survived for shorter periods than did control animals. Of particular interest was the development of severe lactic acidosis in treated animals. Selective analysis of venous blood from various anatomical areas "indicated that the blood returning from the lower extremities had a lower pH than blood from other sites including the mixed venous blood from the right ventricle and probably represented impaired perfusion to the lower extremities caused by the G-suit: T M Such findings are consistent with recent evidence indicating that the pressure garment raises blood pressure by increasing the peripheral resistance rather than by redistributing volume.3, 4 It follows that flow would decrease unless pressure increases suffic-iently to compensate. The 58-year-old man discussed in this report suffered prolonged hypot e n s i o n caused by an overdose of nifedipine. Coma and seizures, and his eventual death, presumably were related to cerebral ischemic injury. He was found to have total occlusion of the arterial circulation to his lower extremities, a complication that was not discovered until several hours after its probable occurrence. Civetta et al2 have provided a list of "potential drawbacks and cautions" concerning use of pressure garments. Annals of Emergency Medicine
Two of these cautions are sustained by this case: "(1) Visual and topical examination of the covered areas is l i m i t e d . . , and (3) Functional i m p a i r m e n t might follow decreased blood flow and result in metabolic acidosis or specific organ dysfunction in covered areas." Delay in discovery of the lower extremity thrombosis in this patient resulted both from the presence of the garment (precluding careful examination initially), and by failure to examine the extremities at the time the garment was removed. It is conceivable that this complication might have arisen without use of the pressure garment; in the presence of atherosclerotic vascular disease with superimposed hypotension, extensive thrombosis could have occurred spontaneously. It seems likely, however, that the MAST garment, inflated to a pressure that probably exceeded the patient's systolic blood pressure for a significant period of time, led to irreversible ischemia, blood stasis, and thrombosis in the lower extremities. SUMMARY This patient suffered prolonged hypotension and coma caused by an overdose of nffedipine. The MAST garment, applied in an effort to help restore blood pressure, was inflated for a total of four hours?The patient's lower extremities were nqt examined immediately upon removal of the garment, but several hours later the legs and scrotum were noted to be ischemic. At surgery, total occlusion of both iliofemoral systems was found. The pat i e n t subsequently died without regaining consciousness. T h r o m b o s i s o f t h e l o w e r extremities appears to be a risk in the use of the MAST garment. It would seem this risk is greater when the blood pressure does not respond to initial measures. Use of the MAST garment should'he.accompanied by careful clinical o b s e r v a t i o n of lower extremity perfusion with Doppler monitoring of pulses; careful examination of the extremities on removal of the garment is necessary. Although the MAST garment has proven value in the prehospital treatment of trauma and s~ock due to blood loss, further evaluation of its use in nonhemorrhagic shock is needed. The author wishes to acknowledge the assistance of David Best, RPA, in researching the literature. 13:12 December 1984
Blood volume displacement with inflation of antishock trousers. Ann Emerg Med 1982;11:409-412. 5. Wayne MA: The MAST suit in the treatment of cardiogenic shock. JACEP 1978;7:107-109.
REFERENCES 1. Lilja GP, Batalden DJ, Adam BE, et ah Value of the counterpressure suit (MAST) in prehospital care. Minn Med 1975;58: 540-543. 2. Civetta JM, Nussenfeld SR, Rowe TR, et ah Prehospital use of the military antishock trouser (MAST). JACEP 1976;5: 581-587. 3. Gaffner FA, Thal ER, Taylor WF, et ah Hemodynamic effects of medical antishock trousers (MAST). J Trauma 1981;21: 931-937. 4. Bivins HG, Knopp R, Tiernan C, et ah
6. Maull KI, Capehart JE, Cardea JA, et ah Limb loss following military anti-shock trousers (MAST) application. J Trauma 1981;21:60-62. 7. Goodenberger D: Thrombosis as complication of MAST use (letter). Ann Emerg Med July 1981;10:395. 8. Huber JA: The MAST suit in cardio-
genie shock (letter). Ann Emerg Med 1982;lh697-698. 9. Lilja GP, Long RS, Ruiz E: Augmentation of systolic blood pressure during external cardiac compression by use of MAST suit. Ann Emerg Med 1981;10: 182-184. 10. McBride G: One caution in pneumatic antishock garment use. JAMA 1982; 247:1112. 11. Wangensteen SL, DeHoll D, Ludewig RM, et ah The detrimental effect of the G-suit in hemorrhagic shock. Ann Surg 1969;170:187-192.
Erratum In the article by Richard H Cales, MD, entitled "Trauma Mortality in Orange County: The Effect of I m p l e m e n t a t i o n of a Regional Trauma System" (January 1984;13:1-10), Figure 3 on page 8 was published w i t h o u t correct labels. A corrected figure appears below. In addition, the motor vehicle fatality rates cited in Table 2 on page 9 should have been cited as deaths/100,000 population/year rather than as deaths/10,000 population/year.
A
B
Prehospital Bypass Deaths
Trauma Facility Deaths
100
100 Response Time
2 r~ 50" % o~
W
rn 50. "6 o~
Treatment Time ~'(4"~ ~73~',~,',;!~5~'tTransport Time
0 0
5
10
15
20
25
30
5
Minutes from Injury N = 73 patients
13:12 D e c e m b e r 1984
10
15
20
25
30 (up)
Minutes from Admission N - 47 patients
Annals of Emergency Medicine
1157/121
Lower Extremity Ischemia Associated with Use of Military Antishock Trousers A 58-year-old m a n was admitted to a c o m m u n i t y hospital following an overdose of nifedipine. Military antishock trousers (MAST) were applied to combat severe hypotension. Blood pressure was restored to 110/50 m m Hg three hours after admission, but the patient remained comatose. Subsequent to MAST garment removal, isehemia of both legs and scrotum was observed; at surgery, both iliofemoral systems were occluded from the aortic bifurcation to the feet. The patient never regained consciousness and died from recurrent ventricular tachycardia. The possible contributing role of the M A S T garment in producing lower e x t r e m i t y ischemia is discussed. [Frampton MW: Lower extremity ischemia associated with use of military antishock trousers. Ann Emerg Med December 1984;13:1155-1157.]
INTRODUCTION
Mark W Frampton, MD Sodus, New York From Myers Community Hospital, Sodus, New York Received for publication November 8, 1983. Revisions received December 19, 1983, and April 2, 1984. Accepted for publication April 11, 1984. Address for reprints: Mark W Frampton, MD, 4418 Ridge Road East, Wiliiamson, New York 14589.
M i l i t a r y antishock trousers (MAST) have gamed increasing acceptance in the t r e a t m e n t of hypotensive states due to t r a u m a or hemorrhage.], 2 External compression of the extremities by the air-inflatable garment raises blood pressure; while traditionally this has been thought to result from volume redistribution, recent evidence indicates the predominant m e c h a n i s m of action m a y be an increase in peripheral resistance.3, 4 Successful use in acute t r a u m a has led to recommendations for expanding their application to nontraumatic conditions as w e l l s Proper use of the garment has been thought to be safe. Literature accomp a n y i n g the e q u i p m e n t (The M A S T Manual, David Clark Co, Worcester, /VIA) m e n t i o n s "frank p u l m o n a r y edema" as the only contraindication. There have occurred, however, reports of lower extremity ischemia following use of the M A S T unit.6, 7 Presented is a case report that raises further questions regarding the safety of pressurized garments in critically ill patients.
CASE REPORT A 58-year-old m a n arrived in the emergency department of a c o m m u n i t y hospital 1V2 hours after ingesting approximately 1 g nifedipine in a suicide attempt. The patient had a history of a diaphragmatic wall myocardial infarction several years previously and subsequent stable angina pectoris. On arrival in the emergency d e p a r t m e n t he was conscious; blood pressure was 60/0 m m Hg; pulse, 120; and respirations, 24. Electrocardiogram (ECG) showed sinus r h y t h m w i t h an inferior scar; central venous pressure was zero. A n intravenous infusion w i t h normal saline was begun, but shortly thereafter b l o o d p r e s s u r e b e c a m e u n o b t a i n a b l e and he suffered loss of consciousness and a respiratory arrest. Heart rate dropped to 35. The patient was intubated; atropine 0.5 mg was administered 1V with increase in the pulse rate to 80. The M A S T garment was applied one hour after arrival and was inflated to less than m a x i m a l pressure (a pressure-monitoring assembly was not available); the abdominal portion of the garment was not inflated. A t the same time 1 g calcium chloride was administered. These measures resulted in a brief rise in the blood pressure to 132/100 m m Hg w i t h i n ten minutes, but 15 m i n u t e s later it was again 60/0 m m Hg. Central venous pressure remained at 0 despite administration of 3,000 cc isotonic saline and 100 mEq sodium bicarbonate. A n additional gram of calcium chloride and continued infusion of saline
13:12 December 1984
Annals of Emergency Medicine
1155/119
ISCHEMIA WITH MAST Frampton
brought the blood pressure up to 80/60 w i t h i n 65 minutes, and to 110/50 m m Hg after another hour. During this time the patient received a total of 5,000 cc saline with potassium chloride and sodium bicarbonate. As blood pressure returned, a femoral pulse was palpable on the left, but was not palpable on the right. The patient remained unconscious with intermittent seizure activity despite subsequent blood pressures ranging from 100/60 m m Hg to 124/80 m m Hg. At 10:00 PM the attending physician gave orders for gradual deflation and removal of the MAST garment over two hours. Blood pressure remained stable during removal of the garment. At 7:00 AM, 14 hours after admission, examination of the lower extremities revealed cool pallor of both legs to the midpelvis, w i t h deep cyanosis of the scrotum. Muscles were stiff and indurated, consistent with hours of total ischemia. Transfer to a central hospital was accomplished, and emergency bilateral femoral embolectomy was performed. At surgery both iliofemoral systems from the aortic bifurcation to the feet were found to be thrombosed. Casts of the iliac arterial system, superficial femoral artery system, and the profunda femoris arteries were removed using a Fogarty catheter. The catheter could not be passed below the popliteal artery on the left side. The patient did not regain consciousness, and died several hours later of refractory ventricular tachycardia.
DISCUSSION "Military antishock trousers" first came into use as a battlefield aid to combat the effects of shock from blood loss until transport to a treatment area could be achieved. Their use in the prehospital accident scene was an outgrowth of this application. Reports of successful use 1 have led to suggestions that the garment may be helpful in other types of shock, including gastrointestinal bleeding, per i p a r t u m bleeding, a n a p h y l a c t i c shock, diabetic ketoacidosis, and drug overdose. 2 One limited study even suggests a use in treating cardiogenic shock, s which has been criticized. 8 The garment also has been used in an attempt to increase effective blood pressure in patients undergoing external cardiac compression; 9 a rise in b l o o d p r e s s u r e of 15 m m was 120/1156
achieved, but there was no other indication of clinical benefit. Reports of adverse effects of MAST use have appeared in the literature. Use in a case of postpartum hemorrhage ended in fatality, found to be the result of air embolus. The authors concluded, " . . . use of this garment may have contributed to this patient's death. "10 Maull et al 6 reported the development of lower extremity compartment syndrome leading to amputation related to prolonged MAST use (48 hours). This occurred despite careful Doppler monitoring of pulses and m e a s u r e m e n t of c o m p a r t m e n t pressures during the course of treatment. In a letter Goodenberger 7 reported occlusion of both femoral arteries by long clots after MAST use in a patient with a leaking aortic aneurysm. An experimental indication of adverse effects came in 1969 f r o m Wangensteen et al, u who applied pressure bladders to dogs after sudden removal of 30% of blood volume. Although blood pressure responded immediately to pressure application, it later fell again, and treated animals actually survived for shorter periods than did control animals. Of particular interest was the development of severe lactic acidosis in treated animals. Selective analysis of venous blood from various anatomical areas "indicated that the blood returning from the lower extremities had a lower pH than blood from other sites including the mixed venous blood from the right ventricle and probably represented impaired perfusion to the lower extremities caused by the G-suit: T M Such findings are consistent with recent evidence indicating that the pressure garment raises blood pressure by increasing the peripheral resistance rather than by redistributing volume.3, 4 It follows that flow would decrease unless pressure increases suffic-iently to compensate. The 58-year-old man discussed in this report suffered prolonged hypot e n s i o n caused by an overdose of nifedipine. Coma and seizures, and his eventual death, presumably were related to cerebral ischemic injury. He was found to have total occlusion of the arterial circulation to his lower extremities, a complication that was not discovered until several hours after its probable occurrence. Civetta et al2 have provided a list of "potential drawbacks and cautions" concerning use of pressure garments. Annals of Emergency Medicine
Two of these cautions are sustained by this case: "(1) Visual and topical examination of the covered areas is l i m i t e d . . , and (3) Functional i m p a i r m e n t might follow decreased blood flow and result in metabolic acidosis or specific organ dysfunction in covered areas." Delay in discovery of the lower extremity thrombosis in this patient resulted both from the presence of the garment (precluding careful examination initially), and by failure to examine the extremities at the time the garment was removed. It is conceivable that this complication might have arisen without use of the pressure garment; in the presence of atherosclerotic vascular disease with superimposed hypotension, extensive thrombosis could have occurred spontaneously. It seems likely, however, that the MAST garment, inflated to a pressure that probably exceeded the patient's systolic blood pressure for a significant period of time, led to irreversible ischemia, blood stasis, and thrombosis in the lower extremities. SUMMARY This patient suffered prolonged hypotension and coma caused by an overdose of nffedipine. The MAST garment, applied in an effort to help restore blood pressure, was inflated for a total of four hours?The patient's lower extremities were nqt examined immediately upon removal of the garment, but several hours later the legs and scrotum were noted to be ischemic. At surgery, total occlusion of both iliofemoral systems was found. The pat i e n t subsequently died without regaining consciousness. T h r o m b o s i s o f t h e l o w e r extremities appears to be a risk in the use of the MAST garment. It would seem this risk is greater when the blood pressure does not respond to initial measures. Use of the MAST garment should'he.accompanied by careful clinical o b s e r v a t i o n of lower extremity perfusion with Doppler monitoring of pulses; careful examination of the extremities on removal of the garment is necessary. Although the MAST garment has proven value in the prehospital treatment of trauma and s~ock due to blood loss, further evaluation of its use in nonhemorrhagic shock is needed. The author wishes to acknowledge the assistance of David Best, RPA, in researching the literature. 13:12 December 1984
Blood volume displacement with inflation of antishock trousers. Ann Emerg Med 1982;11:409-412. 5. Wayne MA: The MAST suit in the treatment of cardiogenic shock. JACEP 1978;7:107-109.
REFERENCES 1. Lilja GP, Batalden DJ, Adam BE, et ah Value of the counterpressure suit (MAST) in prehospital care. Minn Med 1975;58: 540-543. 2. Civetta JM, Nussenfeld SR, Rowe TR, et ah Prehospital use of the military antishock trouser (MAST). JACEP 1976;5: 581-587. 3. Gaffner FA, Thal ER, Taylor WF, et ah Hemodynamic effects of medical antishock trousers (MAST). J Trauma 1981;21: 931-937. 4. Bivins HG, Knopp R, Tiernan C, et ah
6. Maull KI, Capehart JE, Cardea JA, et ah Limb loss following military anti-shock trousers (MAST) application. J Trauma 1981;21:60-62. 7. Goodenberger D: Thrombosis as complication of MAST use (letter). Ann Emerg Med July 1981;10:395. 8. Huber JA: The MAST suit in cardio-
genie shock (letter). Ann Emerg Med 1982;lh697-698. 9. Lilja GP, Long RS, Ruiz E: Augmentation of systolic blood pressure during external cardiac compression by use of MAST suit. Ann Emerg Med 1981;10: 182-184. 10. McBride G: One caution in pneumatic antishock garment use. JAMA 1982; 247:1112. 11. Wangensteen SL, DeHoll D, Ludewig RM, et ah The detrimental effect of the G-suit in hemorrhagic shock. Ann Surg 1969;170:187-192.
Erratum In the article by Richard H Cales, MD, entitled "Trauma Mortality in Orange County: The Effect of I m p l e m e n t a t i o n of a Regional Trauma System" (January 1984;13:1-10), Figure 3 on page 8 was published w i t h o u t correct labels. A corrected figure appears below. In addition, the motor vehicle fatality rates cited in Table 2 on page 9 should have been cited as deaths/100,000 population/year rather than as deaths/10,000 population/year.
A
B
Prehospital Bypass Deaths
Trauma Facility Deaths
100
100 Response Time
2 r~ 50" % o~
W
rn 50. "6 o~
Treatment Time ~'(4"~ ~73~',~,',;!~5~'tTransport Time
0 0
5
10
15
20
25
30
5
Minutes from Injury N = 73 patients
13:12 D e c e m b e r 1984
10
15
20
25
30 (up)
Minutes from Admission N - 47 patients
Annals of Emergency Medicine
1157/121