constipation

Avatar Bowel Program Clinical Study PIEE - Pulsed Irrigation Procedure

(NOTE: The Avatar model was the first model created for the PIE* System)

Veterans Administration Medical Center of Denver and the University of Colorado Medical Center

The Avatar Bowel Evacuation Procedure has been developed for individuals who experience difficulty in episodic or chronic bowel evacuation. The Avatar uses a new principle called PIEE, Pulsed Irrigation for Enhanced Evacuation. Body temperature tap water is pulsed into the rectal ampulla via a speculum. The tap water is infused in short pulses of a few seconds, alternated with a draining period, allowing water and stool to flow by gravity into a sealed container. This process effectively stimulates the nerves of the rectal ampulla to induce peristaltic action or act as a vehicle for stool removal for patients with atonic colons. Concurrently, water pulses act to loosen, disperse, and enhance the removal of stool via the natural lubricating action of the water. A low volume of 25 - 100 cc's of water is infused into the rectum per pulse cycle. A typical pulse cycle is between 1-4 seconds in duration. The maximum pressure does not exceed 2 pounds per square inch.

Methods

The study is divided into three phases. The first phase is the establishment of a baseline of medical data regarding the subject's current bowel program (14 days). The second phase is a 90 day period of time during which subjects replace current bowel programs with the PIEE Procedure on a daily basis for the first 30 days and on alternate days for the next 60 days. The third phase is a 30 day period, during which both manual and medicinal methods directly related to bowel care are replaced such that the Avatar is the sole procedure relating to each subject's bowel care needs. Safety and efficacy were addressed by the following measurements:

Safety of the PIEE Procedure was measured with respect to the following parameters:
1. Blood chemistry (Panel 3 and CBC) during all phases of the study.
2. The mucosal health established by flexible sigmoidoscopy during phase one and upon completion of phase two.
3. Bowel wall integrity established by flexible sigmoidoscopy during phase one and upon completion of phase two.
4. Autonomic dysreflexia or other blood pressure/pulse changes are measured by:
4-a. Average baseline systolic and diastolic pressure and resting heart rate for each subject/incidence of peak systolic/diastolic (in excess of 40 mmHg above resting) during or immediately after completion of the Avatar bowel program. See Charts

Efficacy of the PIEE Procedure was measured relative to each subject's existing bowel program in terms of the following:
1. Change in frequency in bowel related accidents over time.
2. Change in amount of time spent in performing the bowel program on a daily basis.
3. Change in subjective levels of gas present in the colon.
4. Subjective perception of benefits and efficiencies of the PIEE Procedure. See chart for the above.

A total of 22 subjects were selected from the local veterans population of adult males with a history of neurogenic bowel disorders. Fourteen subjects were excluded for geographical, etiological, or pre-existing gastro-intestinal conditions.

Electrolytes Disturbed?

Results - Safety.
Blood electrolytes are not affected in any manner by long-term use of the PIEE Procedure (Table 1)

TABLE1: INDIVIDUAL SUBJECT'S ELECTROLYTES

Days of Study	Sodium	Chloride	Potassium	Calcium	Phosphorus	Incidence of Out of Range
			Patient #1
Baseline	142	102	4.3	9.4	3.9	NONE
30 Day	139	105	4.8	9.6	3.6	NONE
60 Day	140	103	4.6	8.8	3.8	NONE
90 Day	140	103	4.6	8.8	3.8	NONE
			Patient #2
Baseline	141	106	4	9.7	3.9	NONE
30 Day	139	108	3.4	8.7	3.6	NONE
60 Day	143	109	4.1	9.2	3.8	NONE
90 Day	141	108	4.2	9.5	3.6	NONE
			Patient #3
Baseline	141	104	4.5	9.1	3.5	NONE
30 Day	141	107	4.1	9.1	3.5	NONE
60 Day	141	107	4	9	2.7	NONE
90 Day	140	103	4.5	9.2	4.8	NONE
			Patient #4
Baseline	143	111	4.8	9.2	3.6	NONE
30 Day	140	103	3.8	8.4	3.3	NONE
60 Day	139	105	4.1	9	3.2	NONE
90 Day						NONE
			Patient #5
Baseline	137	96	3.5	8.8	4.4	NONE
30 Day	132	91	3.5	9	3.8	NONE
60 Day	136	99	3.6	8.6	3.6	NONE
90 Day	139	105	4.1	9	3.2	NONE
			Patient #6
Baseline	142	106	4.8	10.9	3.4	NONE
30 Day	142	106	4.8	10.9	3.4	NONE
60 Day	142	106	4.4	10.4	3	NONE
90 Day	141	107	4.2	10.4	3	NONE
			Patient #7
Baseline	140	105	4.2	9	4.2	NONE
30 Day	138	102	4.7	8.9	3.5	NONE
60 Day	137	101	3.8	8.9	3.2	NONE
90 Day	136	99	3.8	8.5	3.6	NONE

Blood Elements?

The blood elements of hemoglobin, hematocrit, and WBC are not affected by the PIEE Procedure (Table 2).

Table #2

INDIVIDUAL SUBJECT HEMOGLOBIN, HEMATOCRIT AND WBC OVER 90 DAYS OF THE STUDY

Days of Study	Hemoglobin	Hematocrit	WBC	Incidence of Out of Range
		Patient #1
Baseline	17.90	53.30	6.30	NONE
30 Day	18.70	56.80	5.70	NONE
60 Day	18.20	54.50	6.20	NONE
		Patient #2
Baseline	15.80	46.70	5.90	NONE
30 Day	15.60	47.00	5.10	NONE
60 Day	15.40	45.20	5.50	NONE
90 Day	15.70	46.30	5.20	NONE
		Patient #3
Baseline	16.20	48.70	10.40	WBC
30 Day	16.20	50.90	9.50	NONE
60 Day	16.70	51.30	7.10	NONE
90 Day	16.90	50.50	7.20	NONE
		Patient #4
Baseline	16.30	48.20	10.50	WBC
30 Day	17.30	50.30	15.90	WBC
60 Day	17.50	50.90	7.70	NONE
90 Day	15.40	44.20	4.70	NONE
		Patient #5
Baseline	16.40	47.50	4.20	NONE
30 Day	16.90	51.00	4.20	NONE
60 Day	16.60	48.50	5.00	NONE
		Patient #6
Baseline	15.30	46.70	6.40	NONE
30 Day
60 Day	15.60	47.50	7.10	NONE
90 Day	15.00	44.60	6.90	NONE
		Patient #7
Baseline	13.80	41.10	4.90	NONE
30 Day	14.00	41.40	4.30	NONE
60 Day	14.80	43.80	4.20	NONE
90 Day	15.40	44.20	4.70	NONE

Blood Pressure?

The resting blood pressure and the resting pulse rate of the person using the PIEE Procedure are not affected in any manner over long term use (Table 3).

Table #3

MEAN AND STD. DEV. OF RESTING B/P AND HEART RATE

SYSTOLIC

		Std. Dev.	Phase II Mean	Std. Dev.
Patient #1	125	6	128	7
Patient #2	130	0*	115	7
Patient #3	109	1	93	12
Patient #4	130	5	143	5
Patient #5	105	6	107	10
Patient #8	115	0	114	7
Patient #9	153	5	131	12
Patient #11	112	0*	112	5

DIASTOLIC

	Baseline Mean	Std. Dev.	Phase II Mean	Std. Dev.
Patient #1	81	8	81	3
Patient #2	80	0	71	8
Patient #3	76	11*	63	8
Patient #4	98	1	105	6
Patient #5	78	4	74	9
Patient #8	77	8	76	8
Patient #9	96	6	90	10
Patient #11	72	0*	78	8

PULSE

	Baseline Mean	Std. Dev.	Phase II Mean	Std. Dev.
Patient #1	84	6	81	82
Patient #2	59	0	71	70
Patient #3	90	8*	63	81
Patient #4	71	3	105	72
Patient #5	85	7	74	88
Patient #8	86	10	76	82
Patient #9	63	4	90	75
Patient #11	88	0*	78	76

1 Test: For each of the 3 measurements of vital signs, there was no significant difference in the mean value between baseline and Phase II to a 95% confidence limit.

F Test: For each of the 3 measurements of vital signs, there was no significant difference in the variances Between Baseline and Phase II to a 98% confidence limit.

*Sample size of 1 or no change in daily resting B/P

Autonomic Dysreflexia?

The PIEE Procedure shows a positive improvement regarding vital signs (reflective of autonomic dysreflexia with respect to prior bowel programs) (Figure 1).

Figure 1

RESULTS – EFFICACY

The subjects' responses to the PIEE Procedure are expressing preference toward the procedure over their prior programs (Table 5).

Table 5

SUBJECTIVE RESPONSES OF STUDY SUBJECTS

Subjective Criteria:		Response:
	Better	As Good	Worse
Overall Rating: Avatar vs. Baseline	8	0	0
	More	No Change	Less
Amount of Bowel Gas	0	2	6
	More	Same	or Less
Confidence regarding bowel control	5		3
	Yes		No
Is the Avatar program comfortable?	7		1
Is time saved using PIE?	5		3
Have more bowel control?	6		2
Wish to continue with PIE?	8		0
Will continue to use if VA pays cost?	8		0
Continue at personal expense?	3		5