Objective Evaluate the effects of ultrasound-guided plane block of the right lower rib transverse abdominis muscle on respiratory and circulatory function, as well as T lymphocyte subsets, in patients undergoing liver cancer resection. Methods A total of 173 liver cancer patients admitted to our hospital from January 2021 to January 2024 were selected. They were divided into an experimental group (n=91) and a control group (n=82) based on whether they underwent ultrasound-guided transversus abdominis plane block (TAPB) of the right subcostal region before surgery for pain relief. After a 1:1 match using the propensity score matching (PSM) method, there were 50 cases in each group. Compare clinical data of two groups of patients, measure and statistically analyze respiratory and circulatory function indicators, levels of T lymphocyte subsets, and the use of adjuvant analgesics. Establish GEE models to analyze respiratory and circulatory function indicators, as well as T lymphocyte subsets levels of patients before and after anesthesia, across various anesthesia methods. Results At T2, T3, and T4, compare heart rate (HR), respiratory rate (RR), mean arterial pressure (MAP), end-expiratory carbon dioxide pressure (PETCO2), tidal volume airway pressure (Paw), pulse oxygen saturation (SpO2), CD3+, CD4+, CD8+, and CD4+/CD8+between two groups of patients. The difference between groups is statistically significant (P<0.05). The comparison results within the group showed that the respiratory and circulatory function indicators of the two groups of patients fluctuated in a wave-like pattern. Compared with T0, both groups of patients showed an increase in CD3+ CD4+ and CD4+/CD8+ cells, while CD8+ cells decreased at T2, T3, and T4, with statistically significant differences. The differences were statistically significant (P<0.05). Compared with the control group patients, the patients in the experimental group had lower levels of postoperative patient-controlled intravenous analgesia (PCIA) opioid use equivalent to morphine and remedial dexamethasone use equivalent to morphine (P<0.05). The Generalized Estimating Equations (GEE) model indicates that the experimental group exhibited smoother fluctuations in respiratory and circulatory function indicators HR The fluctuations of RR, MAP, PETCO2, Paw, and oxygen saturation (SpO2) compared to the control group. The T lymphocyte subpopulation levels, specifically CD3+, CD4+, CD8+, and CD4+/CD8+ ratios, showed better improvement in the experimental group than in the control group, with statistically significant (P<0.05). HR, PETCO2, Paw, CD3+, CD4+, and CD4+/CD8+ increased by 1.656, 2.288, 1.957, 1.148, 1.548, and 1.677, respectively. Meanwhile, RR, MAP, SpO2, and CD8+decreased by 1.172, 2.532, 1.673, and 1.483, respectively. Conclusion Ultrasound-guided plane block of the transverse abdominis muscle at the right costal margin can enhance respiratory and circulatory function, modify T lymphocyte subsets in patients undergoing liver cancer resection, and decrease the need for postoperative adjuvant analgesics.