WBC and PLT trends after Splenectomy

Ali Ardestani, MD, MSc, Roger T Lis, Msc, Eric Sheu, MD, PHD, Ali Tavakkoli. Brigham and Women’s Hospital

Background: The White Blood Cell (WBC) and Platelet (PLT) counts typically increase after a splenectomy. These changes make interpretation of postoperative lab values difficult and may unduly raise concerns for complications. Furthermore various thresholds for clinical intervention based on WBC and PLT has been introduced, but there is little evidence to support these criteria. We set out to evaluate complications in a cohort of splenectomy patients and correlate changes in postoperative WBC and PLT counts to the probability of developing a complication.

Methods: We reviewed our patient data registry and identified patients who had undergone an elective Laparoscopic (Lap) or Open Splenectomy over 10 years. Postoperative blood values were made to a ratio compared to immediate postoperative values to document a trend in the postoperative period. We used NSQIP definitions and performed a chart review to calculate morbidity and mortality rates. Analysis was performed on an intention to treat basis.

Results: We identified 251 patients who have undergone splenectomy. Seventy (28%) patients had undergone a Lap splenectomy while 181 were done through an open approach (Table 1). Overall post-operative morbidity was 18.7% (n=47) with 5.2% (n=13) requiring reoperation. Conversion rate was 3% and overall mortality rate was 3.2%. 5.2% (n=13) patients experienced thromboembolic complications. 39% of patients who had a postoperative PLT of more than 1 milion/mcL experienced a thromboembolic event in comparison to only 5% of patients with PLT of less than 1 million (p=0.001). While none of the 56 patients with ITP experienced a thromboembolic event, 4/24 (14.3%) of patients with myeloproliferative/myelodysplastic disorders suffered from a thromboembolic event. Open patients experienced an increase in post-operative WBC ratio in contrast to Lap cases (1.1 fold vs. 0.8, open vs. lap on POD#2; p<0.01). A similar observation was made amongst patients with complications vs. no complication; 1.4 fold increase in WBC vs. 1.0 on POD#2 (p=0.04) (Figure 1).

Conclusions: Lap splenectomy leads to shorter length of stay, lower morbidity and mortality. A peak post-operative PLT count of >1million and myeloproliferative/myelodysplastic disorders are associated with increased thromboembolic events highlighting the need for enhanced DVT prophylaxis measures in this cohort. An increasing postoperative WBC is concerning for an infection and shold initite further workup. The similar WBC upward trend observed in early postoperative days in the Open patients and patients with complications, highlightis the impact of laparoscopy to reduce the complications by minimizing the inflammatory response.