Coagulation Hastened by Splanchnic Stimulation
That splanchnic stimulation accelerates the clotting of blood, and that the effects vary in different animals, are facts illustrated in the following cases:
Oct. 25.—A cat was etherized and maintained in uniform ether anesthesia. After forty minutes of preliminary observation the left splanchnic nerves were stimulated in the abdomen. Following are the figures which show the effects on the coagulation time:
| 3.00 | 4 | minutes |
| .07 | 5.5 | “ |
| .14 | 4 | “ |
| .32 | 4.5 | “ |
| .39 to .40 | Stimulation of left splanchnic. | |
| .42 | 5 | minutes |
| .49 | 5 | “ |
| .56 | 2 | “ |
| 4.00 | 1 | “ |
| .03 | 2.5 | “ |
| .07 | 2.5 | “ |
| .11 | 3 | “ |
| .16 | 2 | “ |
| .20 | 1.5 | “ |
| .23 | 4 | “ |
| .29 | 5.5 | “ |
| .40 | 5.5 | “ |
| .50 | 5 | “ |
In this instance at least ten minutes elapsed between the end of stimulation and the beginning of faster clotting. The period of faster clotting, however, lasted for about a half-hour, during which the coagulation time averaged 2.1 minutes, only forty-three per cent of the previous average of 4.8 minutes. It is noteworthy that the curve (see [Fig. 29]), while lower, shows oscillations not unlike those which follow injection of adrenin (see [p. 155]).
Figure 29.—Shortening of coagulation time after stimulation of the left splanchnic nerves, 3:39–:40.
The primary delay of the effect is not always, indeed it is not commonly, present:
Nov. 6.—A cat was anesthetized (1.40 p.m.) with urethane, and later (3.05) its brain was pithed. The following observations on the coagulation time show the prompt effect of splanchnic stimulation:
| 3.36 | 7 | minutes |
| .46 | 6 | “ |
| 4.02 to .05 | Stimulation of left splanchnic in abdomen. | |
| .08 | 4 | minutes |
| .10 | 3 | “ |
| .18 | 3.5 | “ |
| .23 | 6.5 | “ |
In [Fig. 30] is presented the original record of the shortening of the coagulation after stimulation of the left splanchnic nerve (Nov. 8) in a cat with brain pithed.
Figure 30.—About one-third original size. Record of shortening of coagulation time after stimulation of the left splanchnic nerves, 4:33-:35. The time before stimulation was 6 minutes, and afterwards, 3, 4, 4, 4.5, and 6 minutes.
In the foregoing instances the coagulation time was reduced after splanchnic stimulation to less than half what it was before. The reduction was not always so pronounced.
Nov. 7.—A cat[*] maintained in uniform ether anesthesia with artificial respiration had the following changes in the clotting time of its blood as the result of stimulating the left splanchnic nerve in the thorax:
| 3.40 | 5 | minutes |
| .45 | 5 | “ |
| .51 | 5.5 | “ |
| .58 to 4.00 | Stimulation of left splanchnic. | |
| 4.01 | 4.5 | minutes |
| .06 | 3.5 | “ |
| .11 | 4 | “ |
| .16 | 3.5 | “ |
| .21 | 4 | “ |
| .26 | 4.5 | “ |
| .31 | 5 | “ |
| .36 | 6.5 | “ |
[*] This animal had just passed through a period of excitement with rapid clotting.
In this case the average for about fifteen minutes before stimulation was slightly over five minutes, and for twenty-five minutes thereafter it was four minutes.
In all cases thus far the period of shortened coagulation lasted from ten to thirty minutes. In other cases, however, the effect was seen only in a single observation. If this had occurred only once after splanchnic stimulation, it might be attributed to accident, but it was not an infrequent result, e. g.:
Oct. 28.—A cat was etherized and decerebrated, and the splanchnic nerves were isolated in the thorax. Following are two instances of brief shortening of coagulation after splanchnic stimulation:
| 3.36 | 4.5 | minutes |
| .42 | 4.5 | “ |
| .47 to .49 | Splanchnic stimulation. | |
| .51 | 4.5 | minutes |
| .57 | 2 | “ |
| 4.01 | 4 | “ |
| .07 | 4.5 | “ |
| .12 | 5.5 | “ |
| .19 to .22 | Splanchnic stimulation. | |
| .23 | 3.5 | minutes |
| .27 | 4 | “ |
| .33 | 5 | “ |
In the foregoing instance it is noteworthy that the degree of acceleration is not so great after the second stimulation of the splanchnics as it was after the first. This reduction of effect as the nerves were repeatedly stimulated was frequently noted. The following case presents another illustration:
Nov. 12.—A cat was etherized (2.35 p.m.) and the medulla was punctured (piqûre) at 3.12. The operation was without effect. The loss or lessening of effectiveness on second stimulation of the left splanchnic nerves is to be compared with the persistence of effectiveness on the right side:
| 3.40 | 4.5 | minutes |
| .45 | 4.5 | “ |
| .54 to .56 | Stimulation of left splanchnic in abdomen. | |
| 4.00 | 3 | minutes |
| .05 | 2 | “ |
| .10 | 5.5 | “ |
| .16 | 5 | “ |
| .22 to .27 | Stimulation of left splanchnic in abdomen. | |
| .30 | 4 | minutes |
| .34 | 4 | “ |
| .39 | 4 | “ |
| .44 | 4 | “ |
| .48 | 4 | “ |
| .55 to .57 | Stimulation of right splanchnic. | |
| .59 | 3 | minutes |
| 5.02 | 2.5 | “ |
| .07 | 3 | “ |
| .11 | 3 | “ |
| .15 | 5.5 | “ |
| .22 | 5.5 | “ |
The experiments above recorded show that stimulation of the splanchnic nerves results immediately, or after a brief period, in a shortening of the coagulation time of the blood—an effect which in different animals varies in duration and intensity, and diminishes as the stimulation is repeated. The next question was whether this effect is produced through the adrenal glands.