The study of action potential;
BIOELECTRIC POTENTIALS
liii
CHAPTER FOUR
liv
26 parturients (31%) in the tramadol group compared with 24 parturients (29%) in the pentazocine group. While para 6, were the least studied, with only 6 parturients (7%) in the tramadol group and 6 parturients (7%) in the pentazocine group.
Table III shows the labour pain assessment (mean VAS score (±SD)) of the two groups. The mean (±SD) VAS score of the parturients in the two groups before administration of the trial drugs were comparable with no statistical significant difference;
6.932 (±0.866) in the tramadol group compared to 6.912 (±0.774) in the pentazocine group, p=0.878. The mean VAS score (±SD) of the parturients at 30 and 60 minutes after the trial drug administration were 4.990 (±0.894) and 4.299(±0.748) in the pentazocine group compared to 5.585 (±1.105) and 4.798 (±0.733) in the tramadol group respectively, with p-values of <0.001 at both times. There was no statistically significant difference in labour pain intensity (mean VAS score (±SD)) provided in the two groups beyond 60 minutes (including after delivery) of administering the trial drug (Table III). The pain intensity at 2 h after the trial drug administration using the VAS score was 5.891 (±0.721) and 5.873 (±0.735) in the tramadol and pentazocine group respectively, with p=0.874. At 3 h after the trial drug administration the pain intensity was 6.765 (±0.697) and 6.786 (±0.798) in the tramadol and pentazocine group respectively, with p=0.858. While at 4 h after the trial drug administration the mean VAS score was 6.463 (±0.814) and 6.440 (±01.080) in the tramadol and pentazocine group respectively, with p=0.887. Pain intensity immediately after delivery was 5.060 (±1.380) and 5.040 (±1.400) in the tramadol and pentazocine group respectively, with p=0.909. At 2 h after delivery the pain intensity was 3.462 (±0.839) and 3.451 (±0.812) in the tramadol and pentazocine group respectively with p=0.928. While at 4 h after delivery the mean VAS score was 2.868 (±0.468) and 2.907 (±0.525) in the tramadol and pentazocine
lv
group respectively, with p=0.616. All the parturients in both groups had moderate-severe pain (VAS score of 4.00-6.99) either before or after given the trial drugs. The mean VAS score ranged from the lowest of 4.798 (±0.733) to the highest of 6.963 (±0.545) at 1 and 3 h respectively after the i.m tramadol administration. While in the pentazocine group, the mean VAS score ranged between 4.299 (±0.748) and 6.934 (±0.456) at 1 and 7 h respectively after drug administration.
Table IV shows the frequency (%) of parturients that requested for more analgesia.
More parturients in the tramadol group, 35 (42.2%) requested for more analgesia compared to 29 parturients (35.4%) in the pentazocine group, and the p-value was 0.307. The difference is however, not statistically significant.
Table V shows the mean (± SD) time interval between when the first dose of the analgesic was given to the second dose. The mean interval was longer in the tramadol group 248.2 min (±19.4) compared to 245.2 min (±14.7) in the pentazocine group, p=0.66. The difference was not statistically significant.
Table VI shows the frequency (%) distribution of side effects. Twenty parturients (24%) in the pentazocine group had some side effects compared to 11 (13%) in the tramadol group, p=0.067. This is close to the significance level. Nausea was the commonest side effect observed with 13 parturients (15.8%) in the pentazocine compared to 9 parturients (10.8%), p=0.344. Three parturients (3.7%) in the pentazocine group vomited compared to only 1 patient (1.2%) in the tramadol group, and the p-value was 0.367 using the Fisher’s exact test. The difference was also not statistically significant. Sedation was seen in 4 parturients (4.9%) in the pentazocine group compared to only 1 parturient (1.2%) in the tramadol group, p=0.210. This comparison was also done using the Fisher’s exact test and it
lvi
was not statistically significant. All the parturients sedated were in the Ramsay’s sedation score 2-3. There were no cases of respiratory depression or pruritus observed among the two groups.
Table VII shows the distribution of APGAR scores at 1minute after birth of the neonates. There were 80 neonates (96.4%) and 77 neonates (93.9%) with APGAR score of 7 or above at 1 min in the tramadol and pentazocine groups respectively. Conversely, more neonates 5 (6.1%) compared to 3 (3.6%) had APGAR score of less than 7 at 1 min in the pentazocine and tramadol groups respectively. The p-value was 0.496.
Table VIII shows the distribution of APGAR score of the neonates at 5 minutes after birth. Only 1 baby (1.2%) in the pentazocine group compared to none (0%) in the tramadol group had APGAR score of less than 7 (p=0.497). The same baby remained with APGAR score of 5 at 10 minutes.
Table IX shows the distribution of neonates’ SCBU admission of the two groups. Only 1 baby (1.2%) in the pentazocine compared to none (0%) in the tramadol was admitted into SCBU (p=0.497), not statistically significant difference.
Table X shows the distribution of the parturients’ satisfaction. Fewer parturients in the tramadol group 19 (22.9%) compared to the pentazocine group 40 parturients (48.8%) had very good-excellent satisfaction. Conversely, more parturients in the tramadol group 37 (44.6%) compared to 10 parturients (12.2%) had poor-very poor satisfaction, p<0.001. The difference shows that more parturients were significantly more satisfied in the pentazocine group.
Table XI shows the distribution of other maternal and neonatal parameters. The mean duration of labour were 9.24 h (±1.92) and 8.88 h (±1.02) in the pentazocine and
lvii
tramadol groups respectively (p=0.131). The difference was not statistically significant. The interval between when last given analgesic was administered to delivery interval was 192.5 min (±57.1) and 192.6 min (±57.5) in the tramadol and pentazocine groups respectively (p=0.986). The two groups were very similar in this respect. The mean birth weight of the neonates were 3.052 kg (±0.341) and 3.096 kg (±0.347) in the tramadol and pentazocine groups respectively (p=0.406). The mean birth weight difference of the two groups was not statistically significant.
Figure 1 shows the mean (±SD) pulse rate pattern of the two groups. The pre-injection mean (±SD) pulse rates of the parturients were 73 bpm (±16.1) and 72.7 bpm (±16.3) in the tramadol and pentazocine groups respectively (p=0.741). The difference was not statistically significant. And there was no statistically significant difference between the two groups throughout the study period. Also, the mean (±SD) PR of the two groups remained within normal limits throughout the study period. The range of the PR was between 73 bpm and 77 bpm in both groups.
Figure 2 shows the mean (±SD) SBP pattern of the two groups. The mean (±SD) SBP before administration of the trial drugs were 109.5 mmHg (±11.5) and 108.5 mmHg (± 8.72) in the tramadol and pentazocine groups respectively (p=0.465). The two groups were also comparable with no statistically significant difference between the two groups. There was also no statistically significant difference between the two groups’ mean (±SD) SBP and they remain within normal limits throughout the study period. The range of SBP was between 106 and 111 mmHg in the two groups.
Figure 3 shows the mean (±SD) DBP pattern of the two groups. The mean (±SD) DBP before injection of the trial drugs were 65.98 mmHg (±6.73) and 65.05 mmHg (±6.16) in the
lviii
tramadol and pentazocine groups respectively (p=0.357). The two groups were also comparable in this respect, no statistically significant difference. There was also no statistically significant difference in the mean DBP of the two groups and they remained within normal limits throughout the study period. The range of the DBP was between 63 and 67 mmHg in the two groups.
Figure 4 shows the mean (±SD) MAP pattern of the two groups. The mean (±SD) MAP before injection of the trial drugs were 80.49 mmHg (±8.23) and 79.48 mmHg (±7.01) in the tramadol and pentazocine groups (p=0.554). The two groups were also comparable in this respect, no statistically significant difference. There was also no statistically significant difference in the mean MAP of the two groups and they remained within normal limits throughout the study period. The MAP was between 78 and 81 mmHg in both groups.
Figure 5 shows the mean (±SD) RR pattern of the two groups. The median RR before injection of the trial drugs was 12 cpm in both the tramadol and pentazocine groups. The two groups were also comparable in this respect, no statistically significant difference. There was also no statistically significant difference in the median RR of the two groups, and they remained within normal limits throughout the study period, ranged between 11 and 13 cpm.
No case of respiratory depression observed was in the two groups (defined as RR<10 cpm).
Figure 6 shows the comparison of the mean (±SD) FHR of the neonates. Before the injection of the trial drug, the mean (±SD) FHR of the foetuses were 139.3 bpm (±10.2) and 141.11 bpm (±8.34) in the tramadol and pentazocine groups respectively. The p-value was 0.227, not statistically significant. There were also no statistically significant differences between the two groups’ mean FHR, and they remained within normal limits throughout the study period, ranged between 136 and 142bpm.
lix
Figure 7 shows distribution of type of delivery. Fewer parturients in the pentazocine group than in the tramadol groups were delivered via SVD, 74 parturients (90.2%) compared to 78 parturients (93.6%) respectively. Conversely, more parturients in the pentazocine group compared to the tramadol group were delivered by instrumental vaginal delivery, 8 parturients (9.8%) compared to 5 parturients (6.4%) respectively.
TABLE I. CHARACTERISTICS OF THE PARTURIENTS (Results are presented as mean (±SD))
Group T Group P t-value p-value Number of
Parturients 83 82 - -
Age (years) 26.69(± 5.76) 26.890(±6.26) 0.22 0.828 Gestational age
(weeks)
39.43 (± 1.40) 39.24 (±1.31) 0.90 0.370
Weight (kg) 74.04 (± 6.82) 73.98 (±6.24) 0.06 0.953 Height (cm) 167(± 5.44) 166 (± 5.10) 0.91 0.364 BMI (kg/m2) 26.66 (± 2.27) 26.86 (± 1.85) 0.63 0.533
TABLE II. PARTURIENTS’ PARITY (Results are presented as frequency (%))
Parity Group T n=83
Group P n=82
X2-value p-value
lx
0 26 (31%) 24 (29%)
1.08 0.983
1 12 (15%) 15 (18%)
2 14 (17%) 13 (16%)
3 11 (13%) 10 (12%)
4 9 (11%) 7 (9%)
5 5 (6%) 7 (9%)
6 6 (7%) 6 (7%)
TABLE III: PAIN INTENSITY ASSESMENT BY MEAN VAS SCORES (Results are presented as mean (±SD))
Time Group T
n=83
Group P n=82
t-value p-value
Pre-injection 6.932 (± 0.866) 6.912 (+ 0.774) 0.15 0.878 30 min
5.585 (± 1.105) 4.990 (+ 0.894) 3.80 0.000**
60 min
4.798 (± 0.733) 4.299 (+ 0.748) 4.33 0.000**
90 min
5.644 ( ±0.721) 4.990 (±0.655) 1.09 0.275 120 min
5.891 (± 0.721) 5.873 (±0.735) 0.16 0.874 150 min
6.711 (±0.945) 6.696 (±0.954) 0.10 0.921 180 min
6.765 (±0.697) 6.786 (±0.798) 0.18 0.858 210 min
6.963 (±0.545) 6.770 (±0.759) 1.88 0.062 240 min
6.463 (±0.814) 6.440 (±1.080) 1.14 0.887 270 min
5.850 (±1.060) 5.873 (±0.977) 0.16 0.877 300 min
5.891 (±0.721) 5.873 (±0.735) 0.16 0.874
lxi
**- Statistically significant difference, P<0.05
TABLE IV. PARTURIENTS WHO REQUESTED FOR MORE ANALGESIA (Results are presented as frequency (%))
Group T n= 83
Group P n= 82
x2- value
p-value
Yes 35 (42.2%) 29 (35.4%) 1.04 0.307 No 48 (57.8%) 53 (64.4%)
TABLE V. MEAN TIME OF REQUEST FOR MORE ANALGESIA (Results are presented as mean (±SD))
Group T n=83
Group P n=82
t-value p-value 330 min
6.142 (±0.748) 6.012 (±0.945) 0.98 0.328 360 min
6.342 (±0.926) 6.147 (±0.945) 1.34 0.183 390 min
6.893 (±0.428) 6.798 (±0.567) 1.22 0.226 420 min
6.927 (±0.371) 6.934 (±0.456) 0.11 0.914 Immediately
after Delivery 5.060 (±1.38) 5.04 (±1.40) 0.111 0.909 2 hrs after
delivery 3.462 (±0.839) 3.451 (±0.812) 0.09 0.928 4 hrs after
delivery 2.868 (±0.468) 2.907 (±0.525) 0.50 0.616
lxii Time from 1st dose
(min)
248.2 (± 19.4) 245.2 (± 44.7) 0.45 0.66
TABLE VI. DISTRIBUTION OF SIDE EFFECTS (Results are presented as frequency (%))
Group T n = 83
Group P n=82
X2-value p-value
Yes No Yes No
Some side effects
11 (13%)
72 (87%)
20 (24%)
62 (76%)
3.35 0.067
Nausea 9**
(10.8%)
74 (89.2%)
13**
(15.8%)
69 (84.2%)
0.90 0.344
Vomiting 1**
(1.2%)
82 (98.8%)
3**
(3.7%)
79 (96.3%)
## 0.367
Sedation 1 (1.2%)
82 (98.8%)
4 (4.9%)
78 (95.1)
## 0.210
## - Fisher’s exact test
** - Patients were treated with i.v metoclopramide 10mg stat with good effect
TABLE VII. NEONATES’ APGAR SCORES AT 1 MINUTE (Results are presented as frequency (%))
APGAR Score Group T Group P X2-value p-value
lxiii
n=83 n=82
<7 3 (3.6%) 5 (6.1%)
## 0.496
≥7 80 (96.4%) 77 (93.9%)
Total 83 (100%) 82 (100%)
## -Fisher’s exact test
TABLE VIII. NEONATES’ APGAR SCORES AT 5 MINUTE (Results are presented as frequency (%))
APGAR Score Group T n=83
Group P n=82
X2-value p-value
<7 0 (0%) 1 (1.2%)
## 0.497
≥7 83 (100%) 81 (98.8%)
Total 83 82
## -Fisher’s exact test
TABLE IX. SCBU ADMISION IN THE TWO GROUPS (Results are presented as frequency (%)) Group T
n=83
Group P n=82
X2-value p-value
Yes 0 (0%) 1(1.2%) ## 0.497
No 83(100%) 81(98.8%)
## -Fisher’s exact test
TABLE X. PARTURIENTS’ SATISFACTION
lxiv
(Results are presented as frequency (%)) Satisfaction Group T
n=83
Group P n=82
X2-value p-value
Excellent-Very Good
19 (22.9%) 40 (48.8%)
23.40 <0.001**
Good 27 (32.5%) 32 (39.0%) Poor-Very
Poor
37 (44.6%) 10 (12.2%)
**-statistically significant difference, P<0.05
TABLE XI. OTHER PARTURIENTS/NEONATAL DATA (Results are presented as mean (±SD))
Group T n =83
Group P n =83
t-value p-value
Duration of Labour (hr)
8.88 (± 1.02) 9.24 (± 1.92) 1.52 0.131
Interval between last analgesic and
delivery (minutes)
192.5 (±57.1) 192.6 (±57.5) 0.02 0.986
Birth weight (kg) 3.052 (± 0.341) 3.096 (±0.347) 0.83 0.406
lxv
FIG. 1: GRAPH SHOWING MEAN PULSE RATE CHANGES
FIG. 2: GRAPH SHOWING MEAN SYSTOLIC BLOOD PRESSURE CHANGES
71 72 73 74 75 76 77 78
Mean Pulse rate (cpm)
Time (minutes)
Group T Group P
103 104 105 106 107 108 109 110 111 112
Mean SBP changes (mmHg)
Time (Minutes)
Group T Group P
lxvi
FIG. 3: GRAPH SHOWING MEAN DIASTOLIC BLOOD PRESSURE CHANGES
FIG. 4: GRAPH SHOWING MEAN MAP CHANGES
61 62 63 64 65 66 67 68
Pre-injection 30 60 90 120 150 180 210 240 270 300 330 360 390 420 Immed aftr… 2 hrs aftr… 4 hrs aftr…
Mean DBP (mmHg)
Time (Minutes)
Group T Group P
76 77 78 79 80 81 82
Pre-injection 30 60 90 120 150 180 210 240 270 300 330 360 390 420 Immed aftr… 2 hrs aftr delivery 4 hrs aftr delivery
Mean MAP (mmHg)
Time (Minutes)
Group T Group P
lxvii
FIG. 5: GRAPH SHOWING MEAN RESPIRATORY RATE CHANGES
FIG. 6: GRAPH SHOWING MEAN FHR CHANGES
11.4 11.6 11.8 12 12.2 12.4 12.6 12.8 13 13.2 13.4
Mean RR (cpm)
Time (Minutes)
Group T Group P
133 134 135 136 137 138 139 140 141 142 143
Mean FHR (bpm)
Time (Minutes)
Group T Group P
lxviii
FIG 7: BAR CHART SHOWING DISTRIBUTION OF TYPE OF DELIVERY
0 10 20 30 40 50 60 70 80 90
Group T Group P
NUMBER OF PARTURIENTS
SV Delivery Inst. Delvery
lxix