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Portable Surgical Hospitals

Portable Surgical Hospitals


John T. Greenwood, Ph.D.
Chief, Office of Medical History
Office of The Surgeon General, U.S. Army/
Headquarters, U.S. Army Medical Command
Falls Church, Virginia

Origins and Development of the Portable Surgical Hospital

Soon after his arrival in Australia from the Philippines in February 1942, Col. (later Major General) Percy J. Carroll, the chief surgeon of U.S. Army Services of Supply (USASOS) and also the U.S. Army Forces Far East in SWPA (1942-43), had to face the realities of waging war in this primitive and hostile theater. The long distances, wide geographic dispersion of the Army's ground, air, and service forces in SWPA, and the rugged geographical features challenged the existing concept of the chain of evacuation and required a different approach to the location and use of the major mobile and fixed hospitals.  Accordingly, Carroll split the surgical and evacuation hospitals, which varied in size from 400 to 750 beds, into smaller units that were more mobile and better suited to supporting small units then scattered throughout Australia in anticipation of a Japanese invasion.  

Looking beyond Australia to the ground combat units then flowing into the Advanced Base in Papua, Carroll turned to the problems of providing adequate medical and surgical support for the forces that first had to stem the Japanese advance toward Port Moresby and then to assume the offensive north of the Owen Stanley Range.  The terrain, climate, and primitive nature of the existing transportation infrastructure of Papua and New Guinea severely limited the ability of the Allies to conduct successful military operations.  The harsh physical realities of the jungles, swamps, and mountains dictated that tactical operations would be conducted independently by battalion or regimental combat teams rather than entire infantry divisions concentrated for conventional land warfare, as the U.S. Army's prewar doctrine envisioned.   In such conditions, air transportation became critically important for movement and resupply.  However, only a limited number of transport aircraft were then available to move men, equipment, and supplies over the Owen Stanley Range and return the sick and wounded to Port Moresby and Australia.  This put large and heavy hospital units at the end of the line for deployment, well behind troops, weapons, ammunition, food, supplies, and so on.

The full-range of the Army's conventional medical and emergency surgical support could not be deployed.  The surgical, evacuation, or field hospitals would remain many miles in the rear, and the divisional clearing stations were never intended to provide emergency life-saving surgery. With the Army’s larger mobile hospitals unable to assume their traditional role in support of the front line combat units, the chain of evacuation was interrupted at a critical point.  Some sort of interim solution had to be found quickly to provide the necessary surgical services and care to the severely wounded directly behind the front lines. Otherwise, many wounded soldiers would die from either the lack of life-saving surgery at the front or from the long and arduous evacuation trek along jungle trails from the frontal clearing stations to the nearest surgical unit.2 

Operational necessity compelled Carroll to create a new link in the chain of evacuation that could provide the needed front line emergency surgical support between the clearing station and the mobile hospitals to the rear.  Carroll's solution was a light, highly portable, self-contained medical unit that could act as a small station hospital and also be deployed into combat with the troops.  Manned with skilled surgeons and located close to the fighting to render quick, life-saving surgical intervention, the unit could be moved by its own personnel to remain with the infantrymen during fluid operations.  Actually, Carroll envisioned these hospitals as only a temporary solution to a temporary problem presented by the difficulty of evacuating the seriously wounded in jungle warfare.  That problem would be solved as soon as the larger hospitals could move into the combat zone and resume their traditional surgical role in support of the front line troops.3 

During the summer and fall of 1942, Carroll personally experimented with various concepts and configurations of personnel and equipment at the 4th General Hospital in Melbourne.  Under his direction, a team of Medical Corps officers modified the basic War Department T/O&E for a standard 25-bed station hospital (T/O&E 8-560, 22 July 1942) into a new theater T/O and table of basic allowances (T/BA) (T/O 8-508-S-SWPA, 31 October 1942) for a portable hospital of 25-beds.  The new unit was capable of supporting small units in its camp-type version (with 4 female Army nurses and organic vehicles) or battalion and regimental combat teams in its task force version (without the 4 nurses and organic vehicles). Commanded by a Medical Corps captain or major, the new 29-man portable hospital had 4 medical officers (3 general surgeons and a general surgeon/anesthetist) and 25 enlisted men, including 2 surgical and 11 medical technicians.  What really marked a radical departure was that all of the unit's equipment, medical and surgical supplies, and rations could weigh no more than the 29 men could personally transport.

    In September 1942, Carroll formed 25 "provisional"portable hospitals from the theater's fixed and mobile hospitals at a ratio of one portable unit per 250-beds and 2 additional units built from available medical personnel.  Because the surgical demands on the theater’s hospitals were then only minimal, a large number of trained surgeons were available in Australia to man the new units.  The surgeons in many of the initial portable hospitals would set standards of excellence in surgery and care that firmly established the reputation of the portable hospitals throughout the theater.  However, this was not true of all of the units, and in some instances hospital commanders took advantage of this opportunity to unburden themselves of their unproductive and less well qualified surgeons.  Hastily assembled and trained, the portable hospitals suffered from many shortcomings in personnel and equipment, which would soon become obvious in the jungle fighting around Buna.  Probably the single most critical problem was the severe limitation placed on the total weight to assure the unit’s portability.  From the start, this meant that to be portable the unit had to give up medical and surgical equipment and supplies that would have been most useful in the field.5

Another handicap was the lack of a coherent doctrine for the tactical employment of the portable hospitals, along with an explanation of their exact role in the chain of treatment and evacuation within the combat zone.  The Chief Surgeon’s Office promulgated a basic doctrine in September 1942 when the portable hospitals were established, but that doctrine went to the base sections in Australia and the portable hospitals and not to the medical units or surgeons in the Advanced Base in Papua and combat units.   With no actual operational experience as a basis, that doctrine was much more conjectural than concrete.  Late in 1943, Col. George W. Rice, surgeon at MacArthur’s General Headquarters, SWPA, finally developed a coherent doctrine for the tactical employment of the portable surgical hospitals based on actual combat experience since October 1942.  However, this guidance was only distributed theater-wide early in 1944.  Thus, a clearly articulated doctrine on the use of the portable hospitals would come many months after their initial operational use had demonstrated that they indeed were one of the Army Medical Department's most important life-saving wartime innovations.6

U.S. Army Adopts the Portable Hospital

Carroll first reported his plans to build a 25-bed mobile hospital to The Surgeon General in Washington in his report on 27 June 1942.  He provided more detailed information and copies of the tables of organization and basic allowances on 29 August 1942 as he filled out the new units.  Thereafter, he continued to mention the portable hospitals in a very positive light in his monthly reports.  The Surgeon General's Office saw the great potential in SWPA's portable hospitals even before they had seen significant action.  Carroll's new hospital was just exactly the small, mobile hospital that the Army required to support the combat operations of small units in the island-hopping amphibious operations of the Central Pacific and in the mountainous jungles of the China-Burma-India Theater (CBI)  where the larger mobile hospitals were of little or no use.  The Army’s recently created auxiliary surgical groups, consisting of 61 small specialized surgical and shock teams of 4-6 personnel that would augment clearing stations and field and evacuation hospitals in combat operations, were just then getting their initial field test in the fighting in North Africa.  While made up of exceptionally skilled surgeons, these teams normally had to be attached to larger medical units, could not function separately, and lacked the capacity to holding pre- or postoperative patients.  Hence, they were hardly suitable for the conditions that existed in Papua and New Guinea in 1942 and 1943.7

The Surgeon General's Office and the War Department enthusiastically adopted SWPA's new hospital as a regular unit before the first portable hospitals proved their value in the Buna campaign.  The Surgeon General sought and received approval to add 48 of the new portable hospitals to the War Department's troop basis for 1943.  Based on what was learned at Buna, Carroll and his staff revised the T/O and T/BA for the portable hospital in February 1943.   Completing a discussion that Carroll and Col. George W. Rice, the surgeon at GHQ, SWPA, began in December 1942, Headquarters, USASOS also now redesignated the unit as the "portable surgical hospital" to better describe its functions.  In March 1943, following the lead of SWPA, the War Department also designated the new unit as the portable surgical hospital.  Using the revised SWPA T/O and T/BA of 14 February, The Surgeon General's Office developed a standard Table of Organization and Equipment (T/O&E 8-572S, 4 June 1943) for the new regular portable surgical hospital of 4 medical officers and 33 men.  The new T/O&E confirmed organic vehicles for the units, which greatly improved their ability to move with the combat units they supported from mid-1943 on.8

By the end of 1943, the 48 new units were activated, two of which were assigned to SWPA.  Another 15 new units would arrive in the theater during 1944 to support the increasing pace of MacArthur's offensive operations along the northern coast of New Guinea and into the Philippines.  One portable surgical hospital was now allocated per infantry regiment, 3 per division, although additional hospitals were often authorized in larger operations.  During the war, a total of 103 portable surgical hospitals were activated and 78 would serve in various theaters around the world through end of the war--19 in the China-Burma-India, China, or India-Burma theaters; 12 in the Pacific Ocean Area's South and Central Pacific theaters; and 51 in SWPA (4 moved to SWPA from the South Pacific during 1944). Six PSHs were assigned to the European Theater of Operations, but they arrived only after the end of hostilities.  Thus, Carroll's temporary innovation gained significance far beyond SWPA, and the life-saving surgical work performed in all of these hospitals during the war saved the lives of many thousands of critically wounded soldiers and airmen.9

In Retrospect

From the very first, the portable surgical hospital was a compromise solution to meet a dire need. While it had many strengths, the hospital also had numerous weaknesses.  The most important of their shortcomings could be grouped into four major areas: (1) they lacked much of the equipment needed for definitive surgery, especially in the area of anesthesia, due to the weight limitations that were imposed to maintain their portability; (2) they lacked the bed capacity to hold and care for postoperative patients, especially for abdominal cases, prior to evacuation, which the tactical situation dictated more often than the patients’ medical status; (3) the skills and experience of the assigned surgeons, especially after the first year or so, were often insufficient to meet the heavy surgical demands placed on the units; and (4) they were really never entirely self-sufficient and had to operate with larger units for adequate logistical support.10  

While equipment was always a critical concern, it was the skill level of the surgeons that most concerned the surgical consultants of the Sixth and Eighth U.S. Armies in SWPA.  They saw as one of their primary functions the selection of the surgeons for the portable surgical hospitals.  As the war dragged on into 1944, the pool of skilled and experienced surgeons that they could draw on in SWPA shrank as demands rapidly increased for such personnel.  Increasingly, the portable surgical hospitals were manned with younger and less skilled surgeons. This trend actually began with Carroll himself when he insisted that the surgeons assigned to the portable surgical hospitals should ideally be no older than 30 so that they could better endure the physical strains of moving the hospital and operating under exceptionally difficult conditions near the front.  Of course, few 30-year old surgeons had the experience and skills required to handle all of the surgical demands placed on such a hospital unit. Carroll knew this, and the surgical consultants believed that he was trying to protect his USASOS hospitals from losing experienced surgeons to the combat zone hospitals.  In doing this, Carroll violated a critical lesson that had gone unremembered from World War I: that is, the most skilled and experienced surgeons should be posted the farthest forward where their skills were most needed while the less experienced should staff the rear area hospitals under the watchful eye of an older and more experienced surgeon.  Col. I. Ridgeway Trimble, the surgical consultant in SWPA in 1944-45, made the cogent observation in this regard that there was a vast difference between a medical officer "designated" to do surgery and one “trained” to do surgery.  During the latter part of the war, the surgeons assigned to the hospitals frequently fell into the "designated" rather than the "trained" category.11

The portable surgical hospital was created to meet a specific need at a specific time and place.  Because it filled an important need and performed so well, the Surgeon General's Office extended the use of the hospital throughout the U.S. Army.  As the war came to an end, however, no future was envisioned for these hospitals in the postwar Army Medical Department.  On 23 August 1945, even before the war with Japan had ended, a new type of self-contained, mobile hospital unit was established to handle definitive surgery immediately behind the front lines.  Drawing on its extensive wartime operations, the Army Medical Department developed the 60-bed mobile army surgical hospital, better known by its acronym, MASH, as its front line surgical hospital of the future.  The MASH was to be truly mobile, fully staffed with the surgical and medical personnel, and equipped to provide definitive, life-saving surgery and postoperative care for non-transportable patients.  The record and activities of the portable surgical hospitals contributed significantly to the development of the MASH.  However, the greatest achievement of the front line surgeons and men of these hospitals was the lives of the thousands of American soldiers that they saved during the war – just as Percy Carroll had envisioned in 1942.12


1.    Interview, Mary Ellen Condon with Maj. Gen. Percy J. Carroll, 26 Sep 80, pp. 72-74, in National Archives and Records Administration (NARA), Record Group (RG) 319,  Center of Military History Refiles, War Against Japan, "Interview - Percy Carroll, 26 Sept 1980," Folder 8, Box 4 (hereafter CMH Refiles, War Against Japan, will be cited only as RG 319, with folder title and box and folder numbers);  Ltr, Carroll to The Surgeon General, 27 Jun 42, in RG 319, "Reports, U.S. Army Services of Supply, SWPA, 1942-43," Folder 4, Box 12;  Memo, Carroll to Commanding Officers, General, Station, Evacuation, Surgical, and Field Hospitals, "Hospitalization," 7 Jul 42, and Memo, Ch. Surg., USASOS, A25-Bed Hospital Units," n.d., in RG 319,  "Correspondence Regarding Portable Surgical Hospitals, 1942," Folder 59, Box 3.  All

2.    Interview, Condon with Maj. Gen. Carroll, pp. 50-52,  in RG 319, Folder 8, Box 4; Office of Chief Surgeon, USASOS [probably Maj. David A. Chambers], "Portable Hospitals to March 1943," in RG 319, "Correspondence Regarding Portable Surgical Hospitals, 1943," Folder 63, Box 3. 

3.    See note above.

4.    Interview, Condon with Maj. Gen. Carroll, p. 50, RG 319 "Interview – Percy Carroll, 26 Sept 1980," Folder 8, Box 4; Ltr, P.J. Carroll, Surgeon, to Surgeon, Base Sections 1-7,  USA Services of Supply, “Mobile Hospitals,” 8 Jun 42;   Memo, Carroll to Commanding Officers, General, Station, Evacuation, Surgical, and Field Hospitals, "Hospitalization," 7 Jul 42; Memo, Ch. Surg., USASOS, "25-Bed Hospital Units," n.d.; Ltr (GSC 320.3),  Col. L.S. Ostrander, Adj. Gen. to CINC SWPA, "Table of Organization and Table of  Basic Allowance for Portable Hospitals (Provisional)," 31 Oct 42, w/encl, T/O 8-508-S-SWPA, 31 Oct 42, and T/BA, 31 Oct 42, all in  RG 319, "Correspondence Regarding Portable Surgical Hospitals, 1942," Folder 59, Box 3.  War Department, T/O&E 8-560, 22 July 1942, in Tables of Organization Medical Department (Carlisle Barracks, PA:  Medical Field Service School, January 1943), in OMH/OTSG;  Office of     Chief Surgeon, USASOS [probably Maj. David A. Chambers], "Portable Hospitals to March 1943," in RG 319, "Correspondence Regarding Portable Surgical Hospitals, 1943," Folder 63, Box 3. 

5.    Memo, Carroll, Ch. Surg., HQ, USASOS, to All Hospital Commanding Officers, "Personnel of Portable Hospitals," 22 Dec 42, in RG 319, "Correspondence Regarding Portable Surgical Hospitals, 1942," Folder 59, Box 3; Office of Chief Surgeon, USASOS [probably Maj. David A. Chambers], APortable Hospitals to March 1943," n.d.; Ltr, Lt. Col. Simon Warmenhoven, surgeon, 32d Inf. Div., to Col. P. J. Carroll, Chief Surgeon, USASOS, 21 Jan 43, in RG 319, "Correspondence Regarding Portable Surgical Hospitals, 1943," Folder 63, Box 3;  William B. Parsons, “Chapter XII. Southwest Pacific Area: July 1942 through     August 1944,” pp. 688, 693, 700, in B. Noland Carter (ed),  Activities of Surgical Consultants, Vol. II.  Washington, D.C.: Office of The Surgeon General, 1964; Mary Ellen Condon-Rall and Albert E. Cowdrey, Medical Service in the War  against Japan (Washington, D.C.: U.S. Army Center of Military History, 1998),  pp. 72-75, 133-35.

6.    Office of the Chief Surgeon, USASOS, "25-Bed Hospital Units," n.d.; Memo,  Col. P.J. Carroll, Chief Surgeon, SOS, "25-Bed Hospital Units Additional General Remarks," 24 Sep 42; Draft [Maj. David A. Chambers], "25 Bed Portable Hospital," 22 Oct 42; Memo, Surgeon, Base Section No. 3, to All Hospital Commanders, 7 Sep 42; Col. G. W. Rice, "Tactical Employment of Portable Surgical Hospitals," drafts of 14 Oct 43, 14 Nov 43, and 6 Dec 43, all in RG 319,  "Correspondence Regarding Portable Surgical Hospitals, 1942," Folder 59, Box  3.

7.    Ltr, Col. Percy J. Carroll, Ch. Surg., USASOS, to The Surgeon General, "Medical Services in Australia," 27 Jun 42, w/encls; Ltr, Col. Percy J. Carroll, Ch. Surg., USASOS, to The Surgeon General, "Medical Service in Australia," 29 Aug 42; Encl 3,  "Personnel,” 15 Dec 42, to Ltr, Carroll, Chief  Surg, USASOS, to TSG, "Medical Service in Australia," 15 Dec 42, w/encls; Section 3, "Personnel,"1 Feb 43, encl to Ltr, Carroll,
Chief Surg, USASOS, to TSG, "Medical Service in Australia," 1 Feb 43, w/encls; Section 3, "Hospitalization," 1 Mar 43, encl to Ltr, Carroll, Chief Surg, USASOS, to TSG, “Medical Service in Australia,” 1 Mar 43, w/encls, all in RG 319, "Reports, U.S. Army Services of Supply, SWPA, 1942-43," Folder 4, Box 12.  Clarence McK. Smith, The Medical Department: Hospitalization and Evacuation, Zone of Interior (Washington: Office of The Chief of Military History, 1956), p. 146.  Msg, TSG to CINCSWPA, 11 Feb 43, and  Ltr, Lt. Col. Thomas N. Page, OTSG, to Col. P.J. Carroll, Chief Surgeon,  USASOS, "Portable Hospitals and ‘Jeep’ Evacuation," 9 Feb 43, both in RG 319,  "Correspondence Regarding Portable Surgical Hospitals, 1943," Folder 63, Box 3;   Military Medical Manual, 5th ed., Harrisburg, PA: The Military Service Publishing     Company, 1942, pp. 813, 818, War Department T/O&E 8-571, "Auxiliary Surgical Group," 13 Jul 42;  I. Ridgeway Trimble, "Chapter XII.  Southwest Pacific Area: August 1944 through January 1946," p. 755,  in Carter (ed), Activities of Surgical Consultants, Vol. II.

8.    War Department T/O & E 8-572S, 4 Jun 43, in RG 319, "Organization Portable Surgical Hospital," Folder 27, Box 3; Smith, Hospitalization and Evacuation, pp. 151;  Ltr, Carroll to Miehe, 21 Dec 42, in RG 319, "Correspondence Regarding Portable Surgical Hospitals, 1943," Folder 59, Box 3;  Ltr, AG 322.3. (2-25-43)C, Col. B.M. Fitch, Adj.Gen., GHQ, SWPA, to The Adj. Gen., War Dept., "Special Table of Organization and Table of Basic Allowances for a Portable Hospital (Provisional)," 25 Feb 43, w/encls, T/O 8-508-S-SWPA, "Portable Surgical Hospital," 14 Feb 43, and T/BA, "Portable Surgical Hospital (Capacity: 25 Patients)," 14 Feb 43; Check Sheet, Col. George W. Rice, Surgeon, GHQ, SWPA, to G-3, 22 and 27 Feb 43; RG 319, "Correspondence Regarding Portable Surgical Hospitals, 1943," Folder 63, Box 3.

9.    Col. G. W. Rice, "Tactical Employment of Portable Surgical Hospitals," 14 Oct 43, in RG 319, "Correspondence Regarding Portable Surgical Hospitals, 1943," Folder 59, Box 3; Smith, Hospitalization and Evacuation, pp. 151, 217; Historical Unit, OTSG, "List of Medical Units by Theater World War II," n.d., and "Principal Medical Units Active in the Asiatic-Pacific Theater," n.d. and Steve Everett, "Portable Surgical     Hospitals in World War II," Conference of Army Historians, Washington, DC, 15 June 1994, in OMH/OTSG. 

10.    Frank Glenn, "Chapter XVII.  Sixth U.S. Army," pp. 466, 474, 501, and Frank J. McGowan, "Chapter XIX.  Eighth U.S. Army," pp. 573, 578, in B. Noland Carter, Activities of Surgical Consultants, Vol . I (Washington, D.C.: Office of The Surgeon General, 1962); ; I. Ridgeway Trimble, "Chapter XII. Southwest Pacific Area, August 1944 through January 1946," in Carter (ed), Activities of Surgical Consultants, Vol. II, pp. 715, 755

11.    Glenn, "Sixth U.S. Army," pp. 466, 474, 486-88, 500-01; McGowan, "Eighth U.S. Army," pp. 573, 578; William B. Parsons, "Chapter XII. Southwest Pacific Area: July 1942 through August 1944,” pp. 688, 693, 700, in Carter (ed), Activities of Surgical Consultants, Vol. II and  I. Ridgeway Trimble, "Chapter XII. Southwest Pacific Area: August 1944 through January 1946," in Carter (ed), Activities of Surgical Consultants, Vol. II, pp. 715, 755;  Ltr, Carroll, Chief Surg, USASOS, to The Surgeon General, "Medical Department Activities, S.W.P.A.," 27 Apr 43, p. 2, in RG 319, "Reports, U.S. Army Services of Supply, SWPA, 1942-43," Folder 4, Box 12.

12.    War Department, T/O&E 8-571, "Mobile Army Surgical Hospital (Capacity: 60 bed)," 23 Aug 45, in OMH/OTSG; Albert E. Cowdrey, The Medics’ War (Washington, D.C.:  U. S. Army Center of Military History, 1987), pp. 69-70.  It is interesting to note that when the War Department assigned a TO&E number to the new Mobile Army Surgical Hospital it used the same number, T/O&E 8-571, that had previously been used for the Auxiliary Surgical Group.